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Sample records for rutinemaessig endoskopisk retrograd

  1. [Retrograde ejaculation].

    PubMed

    Malossini, G; Ficarra, V; Caleffi, G

    1999-06-01

    Antegrade ejaculation requires intact anatomy and innervation of the bladder neck. Retrograde ejaculation is an uncommon cause of infertility and can be defined as the escape of seminal fluid from the posterior urethra into the bladder. This pathological condition can result from disturbances at the bladder neck due to anatomical lesions, neuropathic disorders or pharmacological influences. Also congenital and idiophatic causes have been described. The diagnosis may be confirmed by findings sperm in post-coital specimens of urine. Pharmacological manipulation, electro-ejaculation and vibro-ejaculation can be utilized to recovery ejaculation. When anterograde ejaculation in this patients cannot be restored artificial insemination using sperm recovered from the antegrade post-coital urine is indicated. The aim of this paper is to evaluate the data of literature on aetiology and therapy of retrograde ejaculation.

  2. Retrograde gastroesophageal intussusception.

    PubMed

    David, S; Barkin, J S

    1992-01-01

    This is an initial report of spontaneous retrograde gastroesophageal intussusception in an adult. The patient is a 72-yr-old women with a history of ovarian cancer and hiatal hernia, who presented with symptoms of upper gastrointestinal obstruction. Retrograde intussusception was diagnosed endoscopically and confirmed radiographically with an upper gastrointestinal series. Heightened awareness of this entity may lead to its more frequent diagnosis.

  3. Functional (dissociative) retrograde amnesia.

    PubMed

    Markowitsch, H J; Staniloiu, A

    2017-01-01

    Retrograde amnesia is described as condition which can occur after direct brain damage, but which occurs more frequently as a result of a psychiatric illness. In order to understand the amnesic condition, content-based divisions of memory are defined. The measurement of retrograde memory is discussed and the dichotomy between "organic" and "psychogenic" retrograde amnesia is questioned. Briefly, brain damage-related etiologies of retrograde amnesia are mentioned. The major portion of the review is devoted to dissociative amnesia (also named psychogenic or functional amnesia) and to the discussion of an overlap between psychogenic and "brain organic" forms of amnesia. The "inability of access hypothesis" is proposed to account for most of both the organic and psychogenic (dissociative) patients with primarily retrograde amnesia. Questions such as why recovery from retrograde amnesia can occur in retrograde (dissociative) amnesia, and why long-term new learning of episodic-autobiographic episodes is possible, are addressed. It is concluded that research on retrograde amnesia research is still in its infancy, as the neural correlates of memory storage are still unknown. It is argued that the recollection of episodic-autobiographic episodes most likely involves frontotemporal regions of the right hemisphere, a region which appears to be hypometabolic in patients with dissociative amnesia.

  4. Retrograde ejaculation: simpler treatment.

    PubMed

    Leiva, Rene

    2007-07-01

    To report a case of successful treatment of complete retrograde ejaculation by use of a novel, simple, and noninvasive home-based protocol. Case report. Private family medicine clinic. A couple with primary infertility due to the male's complete retrograde ejaculation due to childhood's bladder surgery. The woman was healthy with normal menstrual cycles. After intercourse, the male patient voided a urine-semen mixture from a previously alkalinized urine and proceeded to inseminate it intravaginally into his wife. Determination of best time for intercourse was done by use of the ovulation (Billings) method. This protocol has been used successfully by this couple to conceive two healthy children. To our knowledge, this is the second reported case of successful management of infertility through this protocol. It might be appropriate to try this method first on select patients with retrograde ejaculation.

  5. Focal retrograde amnesia documented with matching anterograde and retrograde procedures.

    PubMed

    Manning, Lilianne

    2002-01-01

    Focal retrograde amnesia is an unusual and theoretically challenging form of memory disorder. The case of a 65-year-old woman presenting with focal retrograde amnesia is reported. Following a cardiac arrest and subsequent hypoxia she remained in a coma for 24 h with evidence of epileptiform activity during the early recovery period. MR scans, 4 and 7 months post-onset, showed mild bifrontal atrophic changes mainly affecting white matter areas. An [18F]fluorodeoxyglucose resting PET scan 1-year post-onset demonstrated right occipito-temporo-parietal hypometabolism. We were able to document the patient's performance on an extensive range of anterograde and retrograde tests and to monitor her recovery of function by assessing her performance at 4, 12 and 24 months post-onset. Spared anterograde memory was observed on a range of verbal and non-verbal tests, including matched tasks that compared pre-illness and post-illness onset recollections. In contrast, her performance on retrograde memory tests, using detailed autobiographical and public events verbal and photographic tasks, showed a temporally-graded retrograde amnesia, more particularly affecting memory for autobiographical episodes. Possible mechanisms underlying CH's focal retrograde amnesia are discussed in terms of Damasio's time-locked multiregional retroactivation model.

  6. Iloperidone-induced retrograde ejaculation.

    PubMed

    Freeman, Scott A

    2013-05-01

    This case series describes the development of retrograde ejaculation with the antipsychotic iloperidone. Iloperidone is a relatively new antipsychotic and has a strong α-1 receptor antagonism, which may explain this rare adverse effect.

  7. Chloroplast signaling: retrograde regulation revelations.

    PubMed

    Beale, Samuel I

    2011-05-24

    Developing chloroplasts are able to communicate their status to the nucleus and regulate expression of genes whose products are needed for photosynthesis. Heme is revealed to be a signaling molecule for this retrograde communication.

  8. The Annual Retrograde Nutation Variability

    NASA Astrophysics Data System (ADS)

    Gattano, C.; Lambert, S.; Bizouard, C.

    2016-12-01

    Very Long Baseline Interferometry is the only technique that can estimate Earth nutations with an accuracy under the milliarcsecond level. With 35 years of geodetic VLBI observations, the principal nutation terms caused by luni-solar tides and geophysical response have been estimated. We focus on the variability. Two of them present very significant amplitude and phase variations: the retrograde Free Core Nutation (FCN) with a period of around 430 days and the Annual Retrograde Nutation (ARN). Despite progress made in global circulation models, the atmospheric and ocean excitation cannot account for that. In particular the ARN shows an amplitude modulation of approximately six years, reminiscent of the six-year geomagnetic oscillation in the Length-of-Day (LOD). As to the latter, we suggest that the nutation term variability may have deep Earth causes, and we estimate an order of magnitude of Earth internal structure parameters to explain this variability.

  9. Making your own retrograde carrier.

    PubMed

    Chai, W L; Ngeow, W C

    1999-02-01

    One of the problems faced by manufacturers is the difficulty in constructing a robust and reliable, angled applicator tip. This can be overcome by handmaking your own retrograde carrier. The applicator tip may be bent to about 50 degrees and, if a kink occurs while bending the tip, it can be replaced easily by a new modified needle. Because the wire used is flexible, it can adapt to the bend without a problem. Narrower carriers can also be made using a 20-G needle, perhaps more suitable for retrograde fillings of molar apices. Because the carrier is designed to be used once only, the problems of it being difficult to load and liable to blockages should not arise.

  10. Retrograde ejaculation in a stallion.

    PubMed

    Brinsko, S P

    2001-02-15

    Retrograde ejaculation was diagnosed in a 10-year-old Arabian stallion. Despite behavioral signs consistent with ejaculation, the collection receptacle of an artificial vagina remained devoid of semen on numerous occasions. Catheterization of the urinary bladder yielded large numbers of spermatozoa, even when an ejaculate was obtained, whereas low numbers (< 1 X 10(6)/ml) of spermatozoa are found in the bladder of clinically normal stallions after ejaculation. Endoscopic examination of the urethra, seminal colliculus, and bladder failed to reveal abnormalities. Medical treatment with imipramine hydrochloride apparently resulted in improvement initially, but was not curative. Further diagnostic and treatment measures were declined and the stallion was castrated. For stallions that seemingly fail to ejaculate or for ejaculates that contain lower seminal volumes or numbers of spermatozoa than expected, obtaining a urine sample after ejaculation via bladder catheterization is a simple diagnostic procedure that may be used to investigate the possibility of retrograde ejaculation.

  11. Endoscopic retrograde sphincterotomy in swine.

    PubMed

    Gholson, C F; Provenza, J M; Doyle, J T; Bacon, B R

    1991-10-01

    Endoscopic retrograde sphincterotomy was performed on four sedated pigs, ages 3-4 months, using a standard human duodenoscope and papillotome. Sphincterotomies, 1 cm in length, were well-tolerated, and all animals recovered promptly, spontaneously regained gastrointestinal function, and gained weight. The first three animals were sacrificed after one week, and autopsy revealed no complications. The fourth animal was sacrificed immediately following the procedure, and no evidence of perforation was found. These observations demonstrate that the pig is a valid experimental model for endoscopic sphincterotomy. Its use in training is limited by technical and anatomic differences from humans. Potential uses of this technique in research are discussed.

  12. Chloroplast retrograde signal regulates flowering

    PubMed Central

    Feng, Peiqiang; Guo, Hailong; Chi, Wei; Chai, Xin; Sun, Xuwu; Xu, Xiumei; Ma, Jinfang; Rochaix, Jean-David; Leister, Dario; Wang, Haiyang; Lu, Congming; Zhang, Lixin

    2016-01-01

    Light is a major environmental factor regulating flowering time, thus ensuring reproductive success of higher plants. In contrast to our detailed understanding of light quality and photoperiod mechanisms involved, the molecular basis underlying high light-promoted flowering remains elusive. Here we show that, in Arabidopsis, a chloroplast-derived signal is critical for high light-regulated flowering mediated by the FLOWERING LOCUS C (FLC). We also demonstrate that PTM, a PHD transcription factor involved in chloroplast retrograde signaling, perceives such a signal and mediates transcriptional repression of FLC through recruitment of FVE, a component of the histone deacetylase complex. Thus, our data suggest that chloroplasts function as essential sensors of high light to regulate flowering and adaptive responses by triggering nuclear transcriptional changes at the chromatin level. PMID:27601637

  13. Screening of seeds prepared from retrograded potato starch to increase retrogradation rate of maize starch.

    PubMed

    Lian, Xijun; Liu, Lizeng; Guo, Junjie; Li, Lin; Wu, Changyan

    2013-09-01

    In this paper, retrograded potato starches treated by oxalic, hydrochloric and citric acids and/with amylase respectively, as seed crystals, are added into maize starch paste to increase maize starch retrogradation rate. The results show that addition of seed accelerates maize starch retrogradation greatly. Seed prepared from retrograded potato starch treated by oxalic acid increases maize starch retrogradation rate most, from 1.5% to 49%. The results of IR spectra of retrograded maize starch derived from different seeds show that double helix, not hydrogen bond, probably forms at stage of seed growth during retrogradation. The results of IR spectra, X-ray and SEM indicate that treatment of retrograded potato starch with oxalic acid leads to formation of more hydrogen bonds and an increase of seed crystal planes, which markedly promotes the growth of the seed. Retrogradation of maize starch by seeding method surely includes a stage of crystal growth through double helix in a way different from normal maize starch retrogradation. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Successful treatment of retrograde ejaculation with amezinium.

    PubMed

    Ichiyanagi, O; Sasagawa, I; Suzuki, Y; Matsuki, S; Itoh, K; Miura, M; Tomita, Y

    2003-01-01

    The effect of amezinium, a new type of antihypotensive agent, on retrograde ejaculation was evaluated in 3 patients with retrograde ejaculation. The patients received 10 mg amezinium orally once a day. All patients achieved antegrade ejaculation. Semen analyses revealed 6-50 x 10(6)/mL (mean 28.7 x 10(6)/mL) sperm with a motility of 20-50% (mean 36.7%). The wives of 2 patients became pregnant within 6 months of the initial treatment. None of the patients had any side effects. It would appear that amezinium is a useful treatment for retrograde ejaculation.

  15. Retrograde arterialized venous flap: an experimental study.

    PubMed

    Moshammer, Harald E T; Schwarzl, Franz X; Haas, Franz M; Maechler, Heinrich; Pierer, Gerhard; Wiltgen, Marco; Koch, Horst

    2003-01-01

    An experimental model was established to study circulation in retrograde arterialized venous flaps (RAVF). Venous flaps measuring 7 x 4 cm with a matching venous system were harvested from both forearms of 10 fresh human cadavers. In each trial, both flaps were simultaneously perfused with heparinized human blood driven by a pulsatile circulation model. In each trial there was one flap with retrograde perfusion, and one flap with antegrade perfusion. Clinical assessment, measurement of outflow, and angiographic examination with digitally assisted assessment after 3 h of perfusion showed better results for retrograde perfusion in 8 of the 10 trials. This study indicates that blood circulation in the periphery of arterialized venous flaps can be enhanced by retrograde arterialization. Copyright 2003 Wiley-Liss, Inc.

  16. Does Perceptual Learning Suffer from Retrograde Interference?

    PubMed Central

    Aberg, Kristoffer C.; Herzog, Michael H.

    2010-01-01

    In motor learning, training a task B can disrupt improvements of performance of a previously learned task A, indicating that learning needs consolidation. An influential study suggested that this is the case also for visual perceptual learning [1]. Using the same paradigm, we failed to reproduce these results. Further experiments with bisection stimuli also showed no retrograde disruption from task B on task A. Hence, for the tasks tested here, perceptual learning does not suffer from retrograde interference. PMID:21151868

  17. Retrogradation enthalpy does not always reflect the retrogradation behavior of gelatinized starch

    PubMed Central

    Wang, Shujun; Li, Caili; Zhang, Xiu; Copeland, Les; Wang, Shuo

    2016-01-01

    Starch retrogradation is a term used to define the process in which gelatinized starch undergoes a disorder-to-order transition. A thorough understanding of starch retrogradation behavior plays an important role in maintaining the quality of starchy foods during storage. By means of DSC, we have demonstrated for the first time that at low water contents, the enthalpy change of retrograded starch is higher than that of native starch. In terms of FTIR and Raman spectroscopic results, we showed that the molecular order of reheated retrograded starch samples is lower than that of DSC gelatinized starch. These findings have led us to conclude that enthalpy change of retrograded starch at low water contents involves the melting of recrystallized starch during storage and residual starch crystallites after DSC gelatinization, and that the endothermic transition of retrograded starch gels at low water contents does not fully represent the retrogradation behavior of starch. Very low or high water contents do not favor the occurrence of starch retrogradation. PMID:26860788

  18. Retrogradation enthalpy does not always reflect the retrogradation behavior of gelatinized starch.

    PubMed

    Wang, Shujun; Li, Caili; Zhang, Xiu; Copeland, Les; Wang, Shuo

    2016-02-10

    Starch retrogradation is a term used to define the process in which gelatinized starch undergoes a disorder-to-order transition. A thorough understanding of starch retrogradation behavior plays an important role in maintaining the quality of starchy foods during storage. By means of DSC, we have demonstrated for the first time that at low water contents, the enthalpy change of retrograded starch is higher than that of native starch. In terms of FTIR and Raman spectroscopic results, we showed that the molecular order of reheated retrograded starch samples is lower than that of DSC gelatinized starch. These findings have led us to conclude that enthalpy change of retrograded starch at low water contents involves the melting of recrystallized starch during storage and residual starch crystallites after DSC gelatinization, and that the endothermic transition of retrograded starch gels at low water contents does not fully represent the retrogradation behavior of starch. Very low or high water contents do not favor the occurrence of starch retrogradation.

  19. Retrograde at the Operational Level of War,

    DTIC Science & Technology

    1987-05-15

    north with forces under Montgomery. There was no mention of a retrograde plan. The first enemy main thrust was along the Eifel region o4 the Ardennes...He planned a detailed retrograde prior to the Chinese attack in 2 anuar- 1to~ he wa;:;s aoin~ to ti-cns ’outr, ceI co a Of ’Seoul if the U.N. Taorces...34Lessons From Korea." Report. Ft. Benning: USAIS. 1954. Liddell Hart. B.H. The German Generals Talk. New York: William Morrow & Co .. 1948

  20. Process for forming retrograde profiles in silicon

    DOEpatents

    Weiner, K.H.; Sigmon, T.W.

    1996-10-15

    A process is disclosed for forming retrograde and oscillatory profiles in crystalline and polycrystalline silicon. The process consisting of introducing an n- or p-type dopant into the silicon, or using prior doped silicon, then exposing the silicon to multiple pulses of a high-intensity laser or other appropriate energy source that melts the silicon for short time duration. Depending on the number of laser pulses directed at the silicon, retrograde profiles with peak/surface dopant concentrations which vary are produced. The laser treatment can be performed in air or in vacuum, with the silicon at room temperature or heated to a selected temperature.

  1. Process for forming retrograde profiles in silicon

    DOEpatents

    Weiner, Kurt H.; Sigmon, Thomas W.

    1996-01-01

    A process for forming retrograde and oscillatory profiles in crystalline and polycrystalline silicon. The process consisting of introducing an n- or p-type dopant into the silicon, or using prior doped silicon, then exposing the silicon to multiple pulses of a high-intensity laser or other appropriate energy source that melts the silicon for short time duration. Depending on the number of laser pulses directed at the silicon, retrograde profiles with peak/surface dopant concentrations which vary from 1-1e4 are produced. The laser treatment can be performed in air or in vacuum, with the silicon at room temperature or heated to a selected temperature.

  2. The Origin of Retrograde Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Naoz, Smadar; Farr, W.; Lithwick, Y.; Rasio, F.; Teyssandier, J.

    2011-09-01

    The search for extra-solar planets has led to the surprising discovery of many Jupiter-like planets in very close proximity to their host star, the so-called ``hot Jupiters'' (HJ). Even more surprisingly, many of these HJs have orbits that are eccentric or highly inclined with respect to the equator of the star, and some (about 25%) even orbiting counter to the spin direction of the star. This poses a unique challenge to all planet formation models. We show that secular interactions between Jupiter-like planet and another perturber in the system can easily produce retrograde HJ orbits. We show that in the frame of work of secular hierarchical triple system (the so-called Kozai mechanism) the inner orbit's angular momentum component parallel to the total angular momentum (i.e., the z-component of the inner orbit angular momentum) need not be constant. In fact, it can even change sign, leading to a retrograde orbit. A brief excursion to very high eccentricity during the chaotic evolution of the inner orbit allows planet-star tidal interactions to rapidly circularize that orbit, decoupling the planets and forming a retrograde hot Jupiter. We estimate the relative frequencies of retrograde orbits and counter to the stellar spin orbits using Monte Carlo simulations, and find that the they are consistent with the observations. The high observed incidence of planets orbiting counter to the stellar spin direction may suggest that planet--planet secular interactions are an important part of their dynamical history.

  3. Studies of retrograde memory: A long-term view

    PubMed Central

    Warrington, Elizabeth K.

    1996-01-01

    Studies of retrograde amnesia are reviewed. First, the issues of temporal gradients of retrograde amnesia are discussed. Second, the question of the anatomical substrates of this syndrome are considered. Finally, some evidence for fractionation of different classes of memoranda within the retrograde time period are presented. PMID:8942966

  4. Retrograde Jejunojejunal Intussusception After Gastrectomy: Report of Four Cases.

    PubMed

    Yoshiya, Shohei; Nakanoko, Tomonori; Koga, Tadashi; Inokuchi, Shoichi; Hirose, Kohsuke; Hirayama, Yoshie; Taketani, Kenji; Yoshida, Rintaro; Minagawa, Ryosuke; Kai, Masanori; Kajiyama, Kiyoshi; Maehara, Yoshihiko

    2015-12-01

    Retrograde intussusception of the small bowel is extremely rare. We experienced four cases of retrograde jejunojejunal intussusception that needed emergency surgery. The aim of the present report was to expand awareness of retrograde jejunojejunal intussusception as an urgent complication following gastrectomy. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  5. Regulation of postsynaptic retrograde signaling by presynaptic exosome release

    PubMed Central

    Korkut, Ceren; Li, Yihang; Koles, Kate; Brewer, Cassandra; Ashley, James; Yoshihara, Motojiro; Budnik, Vivian

    2013-01-01

    SUMMARY Retrograde signals from postsynaptic targets are critical during development and plasticity of synaptic connections. These signals serve to adjust the activity of presynaptic cells according to postsynaptic cell outputs and to maintain synaptic function within a dynamic range. Despite their importance, the mechanisms that trigger the release of retrograde signals and the role of presynaptic cells in this signaling event are unknown. Here we show that a retrograde signal mediated by Synaptotagmin 4 (Syt4) is transmitted to the postsynaptic cell through anterograde delivery of Syt4 via exosomes. Thus, by transferring an essential component of retrograde signaling through exosomes, presynaptic cells enable retrograde signaling. PMID:23522040

  6. Doppler-guided retrograde catheterization system

    NASA Astrophysics Data System (ADS)

    Frazin, Leon J.; Vonesh, Michael J.; Chandran, Krishnan B.; Khasho, Fouad; Lanza, George M.; Talano, James V.; McPherson, David D.

    1991-05-01

    The purpose of this study was to investigate a Doppler guided catheterization system as an adjunctive or alternative methodology to overcome the disadvantages of left heart catheterization and angiography. These disadvantages include the biological effects of radiation and the toxic and volume effects of iodine contrast. Doppler retrograde guidance uses a 20 MHz circular pulsed Doppler crystal incorporated into the tip of a triple lumen multipurpose catheter and is advanced retrogradely using the directional flow information provided by the Doppler waveform. The velocity detection limits are either 1 m/second or 4 m/second depending upon the instrumentation. In a physiologic flow model of the human aortic arch, multiple data points revealed a positive wave form when flow was traveling toward the catheter tip indicating proper alignment for retrograde advancement. There was a negative wave form when flow was traveling away from the catheter tip if the catheter was in a branch or bent upon itself indicating improper catheter tip position for retrograde advancement. In a series of six dogs, the catheter was able to be accurately advanced from the femoral artery to the left ventricular chamber under Doppler signal guidance without the use of x-ray. The potential applications of a Doppler guided retrograde catheterization system include decreasing time requirements and allowing safer catheter guidance in patients with atherosclerotic vascular disease and suspected aortic dissection. The Doppler system may allow left ventricular pressure monitoring in the intensive care unit without the need for x-ray and it may allow left sided contrast echocardiography. With pulse velocity detection limits of 4 m/second, this system may allow catheter direction and passage into the aortic root and left ventricle in patients with aortic stenosis. A modification of the Doppler catheter may include transponder technology which would allow precise catheter tip localization once the

  7. Functional retrograde amnesia: a multiple case study.

    PubMed

    Fujiwara, Esther; Brand, Matthias; Kracht, Lutz; Kessler, Josef; Diebel, Andrea; Netz, Johannes; Markowitsch, Hans J

    2008-01-01

    Functional retrograde amnesia (RA) is a rare pathology and has been rarely studied in detail across different patients. We extensively examined five functional RA patients and compared their neuropsychological profile including anterograde and retrograde memory performance, executive functions, emotional processing, and formally assessed psychiatric symptoms. Across patients, neuropsychological deficits beyond RA were most consistently seen in executive functions and attention suggesting that these dysfunctions contribute to the remote memory deficit. In a majority of the patients, problems in social cognition and emotional behaviour were reflected in Theory of Mind deficits and accompanying psychiatric symptoms. Aberrances in a measure of social desirability were detected, pointing to repressive tendencies in three out of the five patients. Future studies of functional RA patients may investigate more specifically which frontal-lobe associated (dys-) functions contribute to the memory retrieval deficit. Moreover, studying more closely the interaction between social cognition, repressive personality style and memory inhibition in this disease seems worthwhile pursuing.

  8. Retrograde transport on the COG railway.

    PubMed

    Ungar, Daniel; Oka, Toshihiko; Krieger, Monty; Hughson, Frederick M

    2006-02-01

    The conserved oligomeric Golgi (COG) complex is essential for establishing and/or maintaining the structure and function of the Golgi apparatus. The Golgi apparatus, in turn, has a central role in protein sorting and glycosylation within the eukaryotic secretory pathway. As a consequence, COG mutations can give rise to human genetic diseases known as congenital disorders of glycosylation. We review recent results from studies of yeast, worm, fly and mammalian COG that provide evidence that COG might function in retrograde vesicular trafficking within the Golgi apparatus. This hypothesis explains the impact of COG mutations by postulating that they impair the retrograde flow of resident Golgi proteins needed to maintain normal Golgi structure and function.

  9. Treatment of retrograde ejaculation and anejaculation.

    PubMed

    Kamischke, A; Nieschlag, E

    1999-01-01

    Treatment of retrograde ejaculation and anejaculation The various options for the treatment of retrograde ejaculation (RE) and anejaculation (AE) are discussed systematically in this review. A total of 88 studies dealing with patients with RE emphasize medical treatment for reversal of RE and retrieval of spermatozoa from urine. In 136 studies concerning patients with AE, the main emphasis is on medical treatment, electroejaculation (EE) and electrovibration stimulation (EVS) for the reversal of AE. Sperm quality in patients with RE and AE is often impaired. However, with the help of assisted reproduction techniques (ART) available today, both ejaculation disorders can be considered as treatable diseases. The major problem when analysing the studies was the uneven methodological quality of the original articles and the difficulties presented by different drugs and dosages, equipment and techniques, along with different criteria for success. In conclusion, controlled clinical trials comparing different treatment options appear urgently warranted.

  10. Retrograde signaling for climbing fiber synapse elimination.

    PubMed

    Uesaka, Naofumi; Uchigashima, Motokazu; Mikuni, Takayasu; Hirai, Hirokazu; Watanabe, Masahiko; Kano, Masanobu

    2015-02-01

    Neurons form exuberant synapses with target cells early in development. Then, necessary synapses are selectively strengthened whereas unnecessary connections are weakened and eventually eliminated during postnatal development. This process is known as synapse elimination and is a crucial step for shaping immature neural circuits into functionally mature versions. Accumulating evidence suggests that retrograde signaling from postsynaptic cells regulates synapse elimination, but the underlying mechanisms remain unknown. Here, we show that semaphorin3A (Sema3A) and semaphorin7A (Sema7A) mediate retrograde signals for elimination of redundant climbing fiber (CF) to Purkinje cell (PC) synapses in the developing cerebellum, a representative model of synapse elimination in the central nervous system. We picked up candidate retrograde signaling molecules that are expressed in PCs during the period of CF synapse elimination and the receptors of these candidate molecules that are present in CFs. We then assessed the effects of lentivirus-mediated RNAi-knockdown of these molecules on CF synapse elimination. By this systematic screening, we found that knockdown of Sema3A in PCs or its co-receptor, plexinA4 (PlxnA4), in CFs accelerated CF synapse elimination and decreased CF-mediated synaptic inputs. Conversely, knockdown of Sema7A in PCs or either of the two receptors for Sema7A, plexinC1 (PlxnC1) and integrinB1 (ItgB1), in CFs impaired CF synapse elimination. Importantly, the effect of Sema7A involves signaling by type 1 metabotropic glutamate receptor (mGluR1), a canonical pathway in PCs for the final stage of CF synapse elimination. These results demonstrate that specific semaphorins act as retrograde signaling molecules and regulate distinct processes of CF synapse elimination during postnatal cerebellar development.

  11. Retrograde weight implantation for correction of lagophthalmos.

    PubMed

    Kao, Chuan-Hsiang; Moe, Kris S

    2004-09-01

    Gold weight implantation is the most commonly used method for surgical correction of paralytic lagophthalmos. Numerous techniques for placement of the weight have been described, yet complications with these methods continue to occur (implant migration or extrusion, wound infection, failure to correct the lagophthalmos, and excessive postoperative ptosis). We developed a retrograde, postlevator aponeurosis method for implantation to improve the placement and fixation of the weight. This study describes the rationale, technique, and surgical outcome of the retrograde approach. Retrospective analysis. Data maintained and collected on 25 consecutive cases of retrograde upper lid weight implantation for paralytic lagophthalmos. Pre- and postoperative photographs were obtained, and patients were followed for at least 6 months. All procedures were performed by or under the direction of a single surgeon at tertiary academic medical centers (University of California, San Diego and University of Zurich, Switzerland). Twenty-five consecutive patients were evaluated, 16 male and 9 female, ranging in age from 27 to 86 years. There were no surgical failures or perioperative complications and no instances of implant migration or extrusion. One patient developed a delayed infection requiring removal of the implant, and one patient required replacement of the gold weight with a platinum chain implant to better fit the contour of her eyelid. Retrograde implantation allows more accurate placement of the weight while creating a permanent circumferential seal for fixation. The procedure is minimally invasive, less traumatic than previous methods, and produces an excellent cosmetic result. The efficacy has been demonstrated in the outcome of the 25 cases described in this study.

  12. Retrograde femoral interlocking nail in complex fractures.

    PubMed

    Anup, Khare; Mehra, M M

    2002-06-01

    Retrograde interlocking nail was used as the method of fixation in 35 different cases of combination of complex femoral fractures. We performed this procedure in fractures of femoral shaft associated with fracture neck femur, pathological fractures of proximal third of femur with trochanteric pathology, ipsilateral fracture of femur and tibia in polytrauma cases with multiple other injuries, in highly obese patients with fracture shaft femur. This technique was also used in cases of pregnancy with fracture shaft femur and in unstable pelvic fracture or dislocation hip associated with fracture shaft femur. Operative technique involved with retrograde insertion of un-reamed, non-cannulated custom made nail through entrance portal in intercondylar notch was applied for fixation of the shaft femur fracture. The other associated fracture around hip was stabilized separately using suitable implant according to type of fracture. In cases of ipsilateral fracture of femur and tibia, femur was stabilized by retrograde interlocking nail and tibia was stabilized by antigrade interlocking nail through same incision at the same sitting. The case was followed up for three years; the average union time was 12 to 18 weeks. Out of 35 cases, 31 cases regained full knee movement. Out of the remaining 4 cases, 2 cases could regain up to 90 degrees of movement, these were old fractures and non-cooperative patients. In one case, patellofemoral arthritis was developed because of an operative error where a nail was not put inside the articular surface. Mal-union was observed in an early case of the series and implant failure was nil. Retrograde interlocking nail was used as the method of fixation in complex fracture problems. Multiple fractures of long bones can be stabilized in one stage, preventing multiple operations at different stages in polytraumatized patients. This resulted in early recovery, lesser hospital stay, and early rehabilitation of patient with good results and is

  13. Retrograde intraaxonal transport of horseradish peroxidase by neurons in octopus.

    PubMed

    Monsell, E M; Cottee, L J

    1980-01-13

    While retrograde axonal transport is the basis of a widely used neuroanatomical method, it has been rigorously demonstrated in vivo only in a few vertebrate species and not yet in an invertebrate. Evidence is presented that motor neurons of the octopus stellate ganglion are capable of retrograde intraaxonal transport of horeseradish peroxidase. This demonstration shows that retrograde transport occurs in widely divergent groups of animals, and may be a general property of neurons.

  14. Dynamical lifetimes of asteroids in retrograde orbits

    NASA Astrophysics Data System (ADS)

    Kankiewicz, Paweł; Włodarczyk, Ireneusz

    2017-07-01

    The population of known minor bodies in retrograde orbits (i > 90°) that are classified as asteroids is still growing. The aim of our study was to estimate the dynamical lifetimes of these bodies using the latest observational data, including astrometry and physical properties. We selected 25 asteroids with the best-determined orbital elements. We studied their dynamical evolution in the past and future for ±100 Myr (±1 Gyr for three particular cases). We first used orbit determination and cloning to produce swarms of test particles. These swarms were then input into long-term numerical integrations, and the orbital elements were averaged. Next, we collected the available thermal properties of our objects and we used them in an enhanced dynamical model with Yarkovsky forces. We also used a gravitational model for comparison. Finally, we estimated the median lifetimes of 25 asteroids. We found three objects whose retrograde orbits were stable with a dynamical lifetime τ ˜ 10-100 Myr. A large portion of the objects studied displayed smaller values of τ (τ ˜ 1 Myr). In addition, we studied the possible influence of the Yarkovsky effect on our results. We found that the Yarkovsky effect can have a significant influence on the lifetimes of asteroids in retrograde orbits. Because of the presence of this effect, it is possible that the median lifetimes of these objects are extended. Additionally, the changes in orbital elements, caused by Yarkovsky forces, appear to depend on the integration direction. To explain this more precisely, the same model based on new physical parameters, determined from future observations, will be required.

  15. Retrograde ejaculation, painful ejaculation and hematospermia

    PubMed Central

    Parnham, Arie

    2016-01-01

    Although there has been an increased interest on premature ejaculation in the recent years, our understanding regarding the disorders of retrograde ejaculation, painful ejaculation and hematospermia remain limited. All three of these conditions require a keen clinical acumen and willingness to engage in thinking outside of the standard established treatment paradigm. The development of novel investigational techniques and treatments has led to progress in the management of these conditions symptoms; however, the literature almost uniformly is limited to small series and rare randomised trials. Further investigation and randomised controlled trials are needed for progress in these often challenging cases. PMID:27652230

  16. Retrograde ejaculation, painful ejaculation and hematospermia.

    PubMed

    Parnham, Arie; Serefoglu, Ege Can

    2016-08-01

    Although there has been an increased interest on premature ejaculation in the recent years, our understanding regarding the disorders of retrograde ejaculation, painful ejaculation and hematospermia remain limited. All three of these conditions require a keen clinical acumen and willingness to engage in thinking outside of the standard established treatment paradigm. The development of novel investigational techniques and treatments has led to progress in the management of these conditions symptoms; however, the literature almost uniformly is limited to small series and rare randomised trials. Further investigation and randomised controlled trials are needed for progress in these often challenging cases.

  17. Terminal retrograde turn of rolling rings

    NASA Astrophysics Data System (ADS)

    Jalali, Mir Abbas; Sarebangholi, Milad S.; Alam, Mohammad-Reza

    2015-09-01

    We report an unexpected reverse spiral turn in the final stage of the motion of rolling rings. It is well known that spinning disks rotate in the same direction of their initial spin until they stop. While a spinning ring starts its motion with a kinematics similar to disks, i.e., moving along a cycloidal path prograde with the direction of its rigid body rotation, the mean trajectory of its center of mass later develops an inflection point so that the ring makes a spiral turn and revolves in a retrograde direction around a new center. Using high speed imaging and numerical simulations of models featuring a rolling rigid body, we show that the hollow geometry of a ring tunes the rotational air drag resistance so that the frictional force at the contact point with the ground changes its direction at the inflection point and puts the ring on a retrograde spiral trajectory. Our findings have potential applications in designing topologically new surface-effect flying objects capable of performing complex reorientation and translational maneuvers.

  18. Subtrochanteric fractures after retrograde femoral nailing

    PubMed Central

    Mounasamy, Varatharaj; Mallu, Sathya; Khanna, Vishesh; Sambandam, Senthil

    2015-01-01

    Secondary fractures around femoral nails placed for the management of hip fractures are well known. We report, two cases of a fracture of the femur at the interlocking screw site in the subtrochanteric area after retrograde femoral nailing of a femoral shaft fracture. Only a few reports in the existing literature have described these fractures. Two young men after sustaining a fall presented to us with pain, swelling and deformity in the upper thigh region. On enquiring, examining and radiographing them, peri-implant fractures of subtrochanteric nature through the distal interlocking screws were revealed in both patients who also had histories of previous falls for which retrograde intramedullary nailing was performed for their respective femora. Both patients were managed with similar surgical routines including removal of the existing hardware, open reduction and ace cephallomedullary antegrade nailing. The second case did show evidence of delayed healing and was additionally stabilized with cerclage wires. Both patients had uneventful postoperative outcomes and union was evident at the end of 6 mo postoperatively with a good range of motion at the hip and knee. Our report suggests that though seldom reported, peri-implant fractures around the subtrochanteric region can occur and pose a challenge to the treating orthopaedic surgeon. We suggest these be managed, after initial stabilization and resuscitation, by implant removal, open reduction and interlocking intramedullary antegrade nailing. Good results and progression to union can be expected in these patients by adhering to basic principles of osteosynthesis. PMID:26495251

  19. Terminal retrograde turn of rolling rings.

    PubMed

    Jalali, Mir Abbas; Sarebangholi, Milad S; Alam, Mohammad-Reza

    2015-09-01

    We report an unexpected reverse spiral turn in the final stage of the motion of rolling rings. It is well known that spinning disks rotate in the same direction of their initial spin until they stop. While a spinning ring starts its motion with a kinematics similar to disks, i.e., moving along a cycloidal path prograde with the direction of its rigid body rotation, the mean trajectory of its center of mass later develops an inflection point so that the ring makes a spiral turn and revolves in a retrograde direction around a new center. Using high speed imaging and numerical simulations of models featuring a rolling rigid body, we show that the hollow geometry of a ring tunes the rotational air drag resistance so that the frictional force at the contact point with the ground changes its direction at the inflection point and puts the ring on a retrograde spiral trajectory. Our findings have potential applications in designing topologically new surface-effect flying objects capable of performing complex reorientation and translational maneuvers.

  20. Phytochrome and retrograde signalling pathways coverage to antogonistically regulate a light-induced transcription network

    USDA-ARS?s Scientific Manuscript database

    Plastid-to-nucleus retrograde signals emitted by dysfunctional chloroplasts impact photomorphogenic development, but the molecular link between retrograde and photosensory-receptor signaling has remained undefined. Here, we show that the phytochrome (phy) and retrograde signaling pathways converge a...

  1. Using Kinesthetic Activities to Teach Ptolemaic and Copernican Retrograde Motion

    ERIC Educational Resources Information Center

    Richards, Ted

    2012-01-01

    This paper describes a method for teaching planetary retrograde motion, and the Ptolemaic and Copernican accounts of retrograde motion, by means of a series kinesthetic learning activities (KLAs). In the KLAs described, the students literally walk through the motions of the planets in both systems. A retrospective statistical analysis shows that…

  2. Using Kinesthetic Activities to Teach Ptolemaic and Copernican Retrograde Motion

    ERIC Educational Resources Information Center

    Richards, Ted

    2012-01-01

    This paper describes a method for teaching planetary retrograde motion, and the Ptolemaic and Copernican accounts of retrograde motion, by means of a series kinesthetic learning activities (KLAs). In the KLAs described, the students literally walk through the motions of the planets in both systems. A retrospective statistical analysis shows that…

  3. [Prevalence of retrograde ejaculation in infertility associated to hypospermia].

    PubMed

    Juárez-Bengoa, Armando; Bagnarello-González, Fiorella; Rodríguez-Perdomo, David Francisco; Rodríguez-Yee, Emmanuel

    2011-02-01

    Approximately 14% of couples of reproductive age have a fertility problem, defined as the inability to achieve pregnancy after a year of frequent intercourse without contraceptive protection. To determine the prevalence of retrograde ejaculation in infertile patients with hypospermia and to establish the effects of the treatment. Comparative study. A semen analysis of 207 patients with male infertility with hypospermia was performed. The patients with retrograde ejaculation were identified and its prevalence was calculated. Semen parameters were compared before and after treatment by means of a paired-t test. Hormonal levels also were compared between groups with and without retrograde ejaculation by means of a Mann-Whitney U test. Prevalence of retrograde ejaculation was 3.2% out of 2587 infertile patients. Within the group of 207 patients with hypospermia, 84 had retrograde ejaculation. After the treatment the seminal volume increased (from 1.2 to 1.5 milliliters) and the number of mobile cells increased (from 47.2 to 62.5 millions). The number of sperm in urine decreased (from 22 to 10 per high-power field). The patients with retrograde ejaculation had lower levels of follicle-stimulating hormone, luteinizing hormone and testosterone than those without retrograde ejaculation. Retrograde ejaculation and hypospermia are both considered infrequent but important alterations in infertility. Prevalence of retrograde ejaculation in patients with hypospermia is 40.5%. Treatment increased seminal volume and the number of mobile cells in the ejaculated semen. It is necessary to perform future studies in order to determine the impact of severity of retrograde ejaculation on infertility.

  4. Distant retrograde orbits for the Moon's exploration

    NASA Astrophysics Data System (ADS)

    Sidorenko, Vladislav

    We discuss the properties of the distant retrograde orbits (which are called quasi-satellite orbits also) around Moon. For the first time the distant retrograde orbits were described by J.Jackson in studies on restricted three body problem at the beginning of 20th century [1]. In the synodic (rotating) reference frame distant retrograde orbit looks like an ellipse whose center is slowly drifting in the vicinity of minor primary body while in the inertial reference frame the third body is orbiting the major primary body. Although being away the Hill sphere the third body permanently stays close enough to the minor primary. Due to this reason the distant retrograde orbits are called “quasi-satellite” orbits (QS-orbits) too. Several asteroids in solar system are in a QS-orbit with respect to one of the planet. As an example we can mention the asteroid 2002VE68 which circumnavigates Venus [2]. Attention of specialists in space flight mechanics was attracted to QS-orbits after the publications of NASA technical reports devoted to periodic moon orbits [3,4]. Moving in QS-orbit the SC remains permanently (or at least for long enough time) in the vicinity of small celestial body even in the case when the Hill sphere lies beneath the surface of the body. The properties of the QS-orbit can be studied using the averaging of the motion equations [5,6,7]. From the theoretical point of view it is a specific case of 1:1 mean motion resonance. The integrals of the averaged equations become the parameters defining the secular evolution of the QS-orbit. If the trajectory is robust enough to small perturbations in the simplified problem (i.e., restricted three body problem) it may correspond to long-term stability of the real-world orbit. Our investigations demonstrate that under the proper choice of the initial conditions the QS-orbits don’t escape from Moon or don’t impact Moon for long enough time. These orbits can be recommended as a convenient technique for the large

  5. [Retrograde nailing in a tibial fracture].

    PubMed

    Valls-Mellado, M; Martí-Garín, D; Fillat-Gomà, F; Marcano-Fernández, F A; González-Vargas, J A

    2014-01-01

    We describe a case of a severely comminuted type iiia open tibial fracture, with distal loss of bone stock (7 cm), total involvement of the tibial joint surface, and severe instability of the fibular-talar joint. The treatment performed consisted of thorough cleansing, placing a retrograde reamed calcaneal-talar-tibial nail with proximal and distal blockage, as well as a fibular-talar Kirschner nail. Primary closure of the skin was achieved. After 3 weeks, an autologous iliac crest bone graft was performed to fill the bone defect, and the endomedullary nail, which had protruded distally was reimpacted and dynamized distally. The bone defect was eventually consolidated after 16 weeks. Currently, the patient can walk without pain the tibial-astragal arthrodesis is consolidated. Copyright © 2013 SECOT. Published by Elsevier Espana. All rights reserved.

  6. Evidence for retrograde lithospheric subduction on Venus

    NASA Technical Reports Server (NTRS)

    Sandwell, David T.; Schubert, Gerald

    1992-01-01

    Annular moats and outer rises around large Venus coronas such as Artemis, Latona, and Eithinoha are similar in arcuate planform and topography to the trenches and outer rises of terrestrial subduction zones. On earth, trenches and outer rises are modeled as the flexural response of a thin elastic lithosphere to the bending moment of the subducted slab; this lithospheric flexure model also accounts for the trenches and outer rises outboard of the major coronas on Venus. Accordingly, it is proposed that retrograde lithospheric subduction may be occurring on the margins of the large Venus coronas while compensating back-arc extension is occurring in the expanding coronas interiors. Similar processes may be taking place at other deep arcuate trenches or chasmata on Venus such as those in the Dali-Diana chasmata area of aestern Aphrodite Terra.

  7. Asteroids in Retrograde Orbits: Interesting Cases

    NASA Astrophysics Data System (ADS)

    Kankiewicz, Paweł; Włodarczyk, Ireneusz

    2014-12-01

    We present the most interesting examples of the orbital evolution of asteroids in retrograde orbits (i > 90°). First, we used the latest observational data to determine nominal and averaged orbital elements of these objects. Next, the equations of motion of these asteroids were integrated backward 1 My, taking into account the propagation of observational errors. We used so-called 'cloning' procedure to reproduce the reliability of initial data. We obtained some possible scenarios of the orbit inversion in the past, what is often caused by the long-term influence of outer planets. For two most interesting cases (Apollo and Amor type) we did additional calculations: 100 My in the future. Additionally, we investigated the potential influence of Yarkovski/YORP effects on the long-time orbital evolution.

  8. Selective retrograde transsynaptic transfer of a protein, tetanus toxin, subsequent to its retrograde axonal transport

    PubMed Central

    Schwab, ME; Suda, K; Thoenen, H

    1979-01-01

    The fate of tetanus toxin (mol wt 150,000) subsequent to its retrograde axonal transport in peripheral sympathetic neurons of the rat was studied by both electron microscope autoradiography and cytochemistry using toxin-horseradish peroxidase (HRP) coupling products, and compared to that of nerve growth factor (NGF), cholera toxin, and the lectins wheat germ agglutinin (WGA), phytohaemagglutinin (PHA), and ricin. All these macromolecules are taken up by adrenergic nerve terminals and transported retrogradely in a selective, highly efficient manner. This selective uptake and transport is a consequence of the binding of these macromolecules to specific receptive sites on the nerve terminal membrane. All these ligands are transported in the axons within smooth vesicles, cisternae, and tubules. In the cell bodies these membrane compartments fuse and most of the transported macromolecules are finally incorporated into lysosomes. The cell nuclei, the parallel golgi cisternae, and the extracellular space always remain unlabeled. In case the tetanus toxin, however, a substantial fraction of the labeled material appears in presynaptic cholinergic nerve terminals which innervate the labeled ganglion cells. In these terminals tetanus toxin-HRP is localized in 500-1,000 A diam vesicles. In contrast, such a retrograde transsynaptic transfer is not at all or only very rarely detectable after retrograde transport of cholera toxin, NGF, WGA, PHA, or ricin. An atoxic fragment of the tetanus toxin, which contains the ganglioside-binding site, behaves like intact toxin. With all these macromolecules, the extracellular space and the glial cells in the ganglion remain unlabeled. We conclude that the selectivity of this transsynaptic transfer of tetanus toxin is due to a selective release of the toxin from the postsynaptic dendrites. This release is immediately followed by an uptake into the presynaptic terminals. PMID:92475

  9. PRODUCTION OF NEAR-EARTH ASTEROIDS ON RETROGRADE ORBITS

    SciTech Connect

    Greenstreet, S.; Gladman, B.; Ngo, H.; Granvik, M.; Larson, S.

    2012-04-20

    While computing an improved near-Earth object (NEO) steady-state orbital distribution model, we discovered in the numerical integrations the unexpected production of retrograde orbits for asteroids that had originally exited from the accepted main-belt source regions. Our model indicates that {approx}0.1% (a factor of two uncertainty) of the steady-state NEO population (perihelion q < 1.3 AU) is on retrograde orbits. These rare outcomes typically happen when asteroid orbits flip to a retrograde configuration while in the 3:1 mean-motion resonance with Jupiter and then live for {approx}0.001 to 100 Myr. The model predicts, given the estimated near-Earth asteroid (NEA) population, that a few retrograde 0.1-1 km NEAs should exist. Currently, there are two known MPC NEOs with asteroidal designations on retrograde orbits which we therefore claim could be escaped asteroids instead of devolatilized comets. This retrograde NEA population may also answer a long-standing question in the meteoritical literature regarding the origin of high-strength, high-velocity meteoroids on retrograde orbits.

  10. Using Kinesthetic Activities to Teach Ptolemaic and Copernican Retrograde Motion

    NASA Astrophysics Data System (ADS)

    Richards, Ted

    2012-06-01

    This paper describes a method for teaching planetary retrograde motion, and the Ptolemaic and Copernican accounts of retrograde motion, by means of a series kinesthetic learning activities (KLAs). In the KLAs described, the students literally walk through the motions of the planets in both systems. A retrospective statistical analysis shows that students who participated in these activities performed better on examination questions pertaining to retrograde motion than students who did not. Potential explanations for this result, including the breaking of classroom routine, the effect of body movement on conceptual memory, and egocentric spatial proprioception, are considered.

  11. Retrograde ejaculation following open ureteric reimplantation: a case report.

    PubMed

    Au, Eleanor; Dasgupta, Ranan; Dasgupta, Prokar

    2009-08-18

    Retrograde ejaculation is not a recognized complication of ureteric reimplantation surgery. We describe this unusual complication in a 25-year-old man, with no other cause for his ejaculatory dysfunction. A 25-year-old Caucasian man presented with left hydronephrosis ascribed to a megaureter. Following open reimplantation of the ureter, the patient developed retrograde ejaculation that did not respond to medical therapy. The key result reported here is that retrograde ejaculation is a possible complication of open pelvic surgery, for which patients should receive counselling. This is relevant for both urologists and general physicians who consult relatively young men with ejaculatory difficulties.

  12. Retrograde ejaculation following open ureteric reimplantation: a case report

    PubMed Central

    2009-01-01

    Introduction Retrograde ejaculation is not a recognized complication of ureteric reimplantation surgery. We describe this unusual complication in a 25-year-old man, with no other cause for his ejaculatory dysfunction. Case presentation A 25-year-old Caucasian man presented with left hydronephrosis ascribed to a megaureter. Following open reimplantation of the ureter, the patient developed retrograde ejaculation that did not respond to medical therapy. Conclusion The key result reported here is that retrograde ejaculation is a possible complication of open pelvic surgery, for which patients should receive counselling. This is relevant for both urologists and general physicians who consult relatively young men with ejaculatory difficulties. PMID:19918274

  13. Transfer and capture into distant retrograde orbits

    NASA Astrophysics Data System (ADS)

    Scott, Christopher J.

    This dissertation utilizes theory and techniques derived from the fields of dynamical systems theory, astrodyanamics, celestial mechanics, and fluid mechanics to analyze the phenomenon of satellite capture and interrelated spacecraft transfers in restricted three-body systems. The results extend current knowledge and understanding of capture dynamics in the context of astrodynamics and celestial mechanics. Manifold theory, fast Lyapunov indicator maps, and the classification of space structure facilitate an analysis of the transport of objects from the chaotic reaches of the solar system to the distant retrograde region in the sun-Jupiter system. Apart from past studies this dissertation considers the role of the complex lobe structure encompassing stable regions in the circular restricted three-body problem. These structures are shown to be responsible for the phenomenon of sticky orbits and the transport of objects among stable regions. Since permanent capture can only be achieved through a change in energy, fast Lyapunov indicator maps and other methods which reveal the structure of the conservative system are used to discern capture regions and identify the underpinnings of the dynamics. Fast Lyapunov indicator maps provide an accurate classification of orbits of permanent capture and escape, yet monopolize computational resources. In anticipation of a fully three-dimensional analysis in the dissipative system a new mapping parameter is introduced based on energy degradation and averaged velocity. Although the study specifically addresses the sun-Jupiter system, the qualitative results and devised techniques can be applied throughout the solar system and to capture about extrasolar planets. Extending the analysis beyond the exterior of the stable distant retrograde region fosters the construction of transfer orbits from low-Earth orbit to a stable periodic orbit at the center of the stable distant retrograde region. Key to this analysis is the predictability of

  14. Inhibition of retrograde transport protects mice from lethal ricin challenge.

    PubMed

    Stechmann, Bahne; Bai, Siau-Kun; Gobbo, Emilie; Lopez, Roman; Merer, Goulven; Pinchard, Suzy; Panigai, Laetitia; Tenza, Danièle; Raposo, Graça; Beaumelle, Bruno; Sauvaire, Didier; Gillet, Daniel; Johannes, Ludger; Barbier, Julien

    2010-04-16

    Bacterial Shiga-like toxins are virulence factors that constitute a significant public health threat worldwide, and the plant toxin ricin is a potential bioterror weapon. To gain access to their cytosolic target, ribosomal RNA, these toxins follow the retrograde transport route from the plasma membrane to the endoplasmic reticulum, via endosomes and the Golgi apparatus. Here, we used high-throughput screening to identify small molecule inhibitors that protect cells from ricin and Shiga-like toxins. We identified two compounds that selectively block retrograde toxin trafficking at the early endosome-TGN interface, without affecting compartment morphology, endogenous retrograde cargos, or other trafficking steps, demonstrating an unexpected degree of selectivity and lack of toxicity. In mice, one compound clearly protects from lethal nasal exposure to ricin. Our work discovers the first small molecule that shows efficacy against ricin in animal experiments and identifies the retrograde route as a potential therapeutic target.

  15. Plant Intracellular Transport: Tracing Functions of the Retrograde Kinesin.

    PubMed

    Müller, Sabine

    2015-09-21

    Adding to its varied repertoire of functions in cell morphogenesis and cell division, a molecular motor protein of the kinesin-14 class has recently been implicated in rapid retrograde transport along cellular tracks in moss.

  16. Difficult retrograde endotracheal intubation: the utility of a pharyngeal loop.

    PubMed

    Arya, Virendra K; Dutta, Amitabh; Chari, Pramila; Sharma, Ramesh K

    2002-02-01

    Direct laryngoscopy and tracheal intubation remains the technique of choice to achieve control of the airway. Alternative or additional techniques of airway control are required whenever an airway is deemed difficult because of anatomical and/or technical reasons. The retrograde intubation technique is an important option for gaining airway access from below the vocal cords in such situations (1). We report successful management and the problems encountered while gaining the upper airway by the retrograde catheter method in a patient having bilateral fibrous ankylosis of the temporomandibular joint (TMJ). A 30-yr-old woman presented for redo-release of bilateral temporomandibular joint ankylosis under general anesthesia. During the previous anesthetic for primary release of ankylosis, tracheostomy was done, as conventional blind nasotracheal and retrograde intubation attempts failed several times. This case report describes the method for overcoming the difficulties of a retrograde intubation procedure in removing the guiding catheter nasally by using a pharyngeal loop assembly.

  17. Prostatic urethra malformation associated with retrograde ejaculation: a case report.

    PubMed

    Zhao, Kai; Zhang, Jianzhong; Xu, Aiming; Zhang, Cheng; Wang, Zengjun

    2016-12-21

    Retrograde ejaculation can have anatomical, neurogenic, or pharmacological causes. Among these factors, malformation of the prostatic urethra is an uncommon cause. We describe a 29-year-old Han Chinese man with absence of his verumontanum combined with ejaculatory duct cysts, and no other cause for ejaculatory dysfunction. His verumontanum was replaced by a deep groove adjacent to his bladder neck, which could significantly influence bladder neck contraction. In addition, the large cysts in the ejaculatory duct could obstruct the anterior outlet of his prostatic urethra and prevent seminal fluid flow in an anterograde direction. There are few reports of retrograde ejaculation associated with congenital malformations of the posterior urethra. Malformations associated with bladder neck laxity and increased tone of the prostatic urethral outlet can contribute to retrograde ejaculation. Malformation of the prostatic urethra is an uncommon cause of retrograde ejaculation, and can be difficult to treat.

  18. Fundamental studies of retrograde reactions in direct liquefaction

    SciTech Connect

    Serio, M.A.; Solomon, P.R.; Bassilakis, R.; Kroo, E.

    1989-01-01

    Most of the proposed processing schemes for improving liquefaction yields involve favoring bond-breaking and radical stabilization reactions over the retrograde reactions. The retrograde reactions are often encountered before liquefaction temperatures are reached. The objective of this program is to elucidate and model the retrograde reaction chemistry in direct coal liquefaction through the application of experimental techniques and theoretical models which have been successfully employed at Advanced Fuel Research (AFR) and SRI International (a subcontractor) to understand and predict coal reaction behavior. The study of retrograde reactions is being done using an integrated approach using extensive characterization of the liquefaction chemistry of three kinds of systems: (1) model polymers; (2) coal; and (3) modified coals.

  19. The 'SAFARI' Technique Using Retrograde Access Via Peroneal Artery Access

    SciTech Connect

    Zhuang, Kun Da; Tan, Seck Guan; Tay, Kiang Hiong

    2012-08-15

    The 'SAFARI' technique or subintimal arterial flossing with antegrade-retrograde intervention is a method for recanalisation of chronic total occlusions (CTOs) when subintimal angioplasty fails. Retrograde access is usually obtained via the popliteal, distal anterior tibial artery (ATA)/dorsalis pedis (DP), or distal posterior tibial artery (PTA). Distal access via the peroneal artery has not been described and has a risk of continued bleeding, leading to compartment syndrome due to its deep location. We describe our experience in two patients with retrograde access via the peroneal artery and the use of balloon-assisted hemostasis for these retrograde punctures. This approach may potentially give more options for endovascular interventions in lower limb CTOs.

  20. Endoscopic Retrograde Cholangiopancreatography in Bilioenteric Anastomosis

    PubMed Central

    Park, Eun Taek

    2016-01-01

    For diagnosis and treatment of pancreatobiliary diseases, endoscopic retrograde cholangiopancreatography (ERCP) is useful method nowadays and its technically success rate is usually in about 90%-95% of patients with normal gastric and pancreaticobiliary anatomy. Recently ERCP is significantly challenging after intestinal reconstruction, particularly in patients who have undergone pancreaticoduodenectomy (PD, classic Whipple’s operation) or pylorus-preserving pancreatoduodenectomy (PPPD) with reconstruction. PD and PPPD relate to numerous techniques have been presented for reconstruction of the digestive tract and pancreaticobiliary tree during the resection bilioenteric stricture commonly occurs later in the postoperative course and developed in 5-year cumulative probability of biliary stricture rate of 8.2% and pancreaticoenteric stricture of 4.6%. This complication was no difference in incidence between patients with benign or malignant disease. In PD or PPPD with reconstruction, short pancreatobiliary limb with biliojejunal anastomosis site is made usually, modestly success rate of intubation to blind loop and cannulation with conventional endoscope. However, in combined Reux-en-Y anastomosis, longer pancreatobiliary limb and additional Reux limb are obstacle to success intubation and cannulation by using conventional endoscope. In this situation, new designed enetroscope with dedicated accessories is efficient. PMID:27838918

  1. A reappraisal of retrograde cerebral perfusion

    PubMed Central

    2013-01-01

    Brain protection during aortic arch surgery by perfusing cold oxygenated blood into the superior vena cava was first reported by Lemole et al. In 1990 Ueda and associates first described the routine use of continuous retrograde cerebral perfusion (RCP) in thoracic aortic surgery for the purpose of cerebral protection during the interval of obligatory interruption of anterograde cerebral flow. The beneficial effects of RCP may be its ability to sustain brain hypothermia during hypothermic circulatory arrest (HCA) and removal of embolic material from the arterial circulation of the brain. RCP can offer effective brain protection during HCA for about 40 to 60 minutes. Animal experiments revealed that RCP provided inadequate cerebral perfusion and that neurological recovery was improved with selective antegrade cerebral perfusion (ACP), however, both RCP and ACP provide comparable clinical outcomes regarding both the mortality and stroke rates by risk-adjusted and case-matched comparative study. RCP still remains a valuable adjunct for brain protection during aortic arch repair in particular pathologies and patients. PMID:23977600

  2. San Andreas Fault tremor and retrograde metamorphism

    NASA Astrophysics Data System (ADS)

    Fagereng, Åke; Diener, Johann F. A.

    2011-12-01

    Tectonic tremor is an enigmatic low-frequency seismic phenomenon mainly observed in subduction zones, but also documented along the deep extension of the central San Andreas Fault. The physical mechanisms behind this unusual seismic event are not yet determined for any tectonic setting; however, low effective stress conditions arising from metamorphic fluid production are commonly inferred for subduction-related tremor. We investigate the petrologic conditions at which the San Andreas tectonic tremor is inferred to occur through calculations of the pressure - temperature - time evolution of stable mineral assemblages and their water content in the dominant lithologies of the Franciscan Complex. We find that tremor locations around Parkfield and Cholame are currently experiencing retrograde metamorphic conditions. Within the temperature-depth conditions of observed tremor activity, at approximately 500°C and 20 km depth, several mineralogical transitions may occur in cooling greywacke and mafic rocks, leading to localised, significant removal of free water and an associated volume decrease. This indicates that, contrary to subduction-related tremor, tremor on the San Andreas Fault is not linked to prograde, crustal metamorphic fluid production within the fault zone; rather it might be related to mantle-derived fluids from below the tremor zone, and/or fault zone weakening that occurs as phyllosilicates replace more competent and granular mineral phases.

  3. Complications of internal jugular vein retrograde catheterization.

    PubMed

    Gemma, M; Beretta, L; De Vitis, A; Mattioli, C; Calvi, M R; Antonino, A; Rizzi, B; Crippa, L; D'Angelo, A

    1998-01-01

    We report on the incidence of complications of 172 internal jugular vein retrograde catheterizations (IJVRCs) performed on 126 patients. Standard cannulation and X-ray control of the catheter tip placement were performed. Difficulties encountered during the manouvre were registered. Patients with a jugular catheter in place for more than one day had neck echography on catheter removal and one week later. Carotid artery puncture occurred in 20 (12%) cases and lymphatic vessel puncture in one. In 13 (8%) cases IJVRC failed due to difficulties in advancing the guide. X-ray films documented catheter misplacement in 39 (23%) cases: loop into the internal jugular vein in 11 (6%); paravertebral venous plexus cannulated in one; other extracranial jugular afferent cannulated in 4 (2%); catheter tip into the jugular lumen in 10 (6%); catheter tip beyond the jugular bulb in 13 (8%). First neck echography documented: one perivascular hematoma (absent one week later); 3 (4%) jugular vein thrombosis (2 asymptomatic and absent one week later; one symptomatic and still evident one week later). Positive neck echography was not associated with difficulties, length of catheterization, diameter of the catheter. IJVRC is a simple and safe procedure with a low incidence of serious complications.

  4. Distant retrograde orbits and the asteroid hazard

    NASA Astrophysics Data System (ADS)

    Perozzi, Ettore; Ceccaroni, Marta; Valsecchi, Giovanni B.; Rossi, Alessandro

    2017-08-01

    Distant Retrograde Orbits (DROs) gained a novel wave of fame in space mission design because of their numerous advantages within the framework of the US plans for bringing a large asteroid sample in the vicinity of the Earth as the next target for human exploration. DROs are stable solutions of the three-body problem that can be used whenever an object, whether of natural or artificial nature, is required to remain in the neighborhood of a celestial body without being gravitationally captured by it. As such, they represent an alternative option to Halo orbits around the collinear Lagrangian points L1 and L2. Also known under other names ( e.g., quasi-satellite orbits, cis-lunar orbits, family- f orbits) these orbital configurations found interesting applications in several mission profiles, like that of a spacecraft orbiting around the small irregularly shaped satellite of Mars Phobos or the large Jovian moon Europa. In this paper a basic explanation of the DRO dynamics is presented in order to clarify some geometrical properties that characterize them. Their accessibility is then discussed from the point of view of mission analysis under different assumptions. Finally, their relevance within the framework of the present asteroid hazard protection programs is shown, stressing the significant increase in warning time they would provide in the prediction of impactors coming from the direction of the Sun.

  5. Retrograde Melting and Internal Liquid Gettering in Silicon

    SciTech Connect

    Hudelson, Steve; Newman, Bonna K.; Bernardis, Sarah; Fenning, David P.; Bertoni, Mariana I.; Marcus, Matthew A.; Fakra, Sirine C.; Lai, Barry; Buonassisi, Tonio

    2011-07-01

    Retrograde melting (melting upon cooling) is observed in silicon doped with 3d transition metals, via synchrotron-based temperature-dependent X-ray microprobe measurements. Liquid metal-silicon droplets formed via retrograde melting act as efficient sinks for metal impurities dissolved within the silicon matrix. Cooling results in decomposition of the homogeneous liquid phase into solid multiple-metal alloy precipitates. These phenomena represent a novel pathway for engineering impurities in semiconductor-based systems.

  6. Pleuropancreatic fistula: endoscopic retrograde cholangiopancreatography and computed tomography

    SciTech Connect

    McCarthy, S.; Pellegrini, C.A.; Moss, A.A.; Way, L.W.

    1984-06-01

    The complementary use of endoscopic retrograde cholangiopancreatography and computed tomography in the diagnosis and management of pleuropancreatic fistulas is described in relation to four cases in which computed tomography revealedthe thoracic extension of a pancreatic fistula not demonstrable by endoscopic retrograde cholangiopancreatography, although the latter indicated an abnormal pancreatic duct. The complementary use of both techniques may be necessary to define the pathologic anatomy so that the appropriate therapy, particularly the surgical approach, can be decided.

  7. An unusual cause of retrograde ejaculation and hypertension.

    PubMed

    Widjaja, A; Truss, M C; Rademaker, J; Stief, C B; von zur Mühlen, A

    2000-06-01

    A 39-year-old man presented with a 1-year history of retrograde ejaculation and a 10-year history of drug-resistant hypertension. Diagnostic abdominal ultrasound revealed an open bladder neck during the filling phase and a retroperitoneal tumor. After surgical excision histology revealed an extra-adrenal pheochromocytoma, which should be included in the differential diagnosis of patients presenting with retrograde ejaculation and hypertension.

  8. The inherent catastrophic traps in retrograde CTO PCI.

    PubMed

    Wu, Eugene B; Tsuchikane, Etsuo

    2017-05-04

    When we learn to drive, our driving instructor tells us how to check the side mirror and turn your head to check the blind spot before changing lanes. He tells us how to stop at stop signs, how to drive in slippery conditions, the safe stopping distances, and these all make our driving safe. Similarly, when we learn PCI, our mentors teach us to seat the guiding catheter co-axially, to wire the vessel safely, to deliver balloon and stents over the wire, to watch the pressure of the guiding, in order that we perform PCI safely and evade complications. In retrograde CTO PCI, there is no such published teaching. Also many individual mentors have not had the wide experience to see all the possible complications of retrograde CTO PCI and, therefore, may not be able to warn their apprentice. As the number of retrograde procedures increase worldwide, there is a corresponding increase in catastrophic complications, many of which, we as experts, can see are easily avoidable. To breach this gap in knowledge, this article describes 12 commonly met inherent traps in retrograde CTO PCI. They are inherent because by arranging our equipment in the manner to perform retrograde CTO PCI, these complications are either induced directly or happen easily. We hope this work will enhance safety of retrograde CTO PCI and avoid many catastrophic complications for our readers and operators. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  9. Increased sinusoidal volume and solute extraction during retrograde liver perfusion

    SciTech Connect

    Bass, N.M.; Manning, J.A.; Weisiger, R.A.

    1989-06-01

    Retrograde isolated liver perfusion has been used to probe acinar functional heterogeneity, but the hemodynamic effects of backward flow have not been characterized. In this study, extraction of a long-chain fatty acid derivative, 12-N-methyl-7-nitrobenzo-2-oxa-1,3-diazol-amino stearate (12-NBDS), was greater during retrograde than during anterograde perfusion of isolated rat liver. To determine whether hemodynamic differences between anterograde and retrograde perfused livers could account for this finding, the hepatic extracellular space was measured for both directions of flow by means of (/sup 14/C)sucrose washout during perfusion as well as by direct measurement of (/sup 14/C)sucrose entrapped during perfusion. A three- to fourfold enlargement of the total hepatic extracellular space was found during retrograde perfusion by both approaches. Examination of perfusion-fixed livers by light microscopy and morphometry revealed that marked distension of the sinusoids occurred during retrograde perfusion and that this accounts for the observed increase in the (/sup 14/C)sucrose space. These findings support the hypothesis that maximum resistance to perfusate flow in the isolated perfused rat liver is located at the presinusoidal level. In addition, increased transit time of perfusate through the liver and greater sinusoidal surface area resulting from sinusoidal distension may account for the higher extraction of 12-NBDS and possibly other compounds by retrograde perfused liver.

  10. Efficacy of treatment with pseudoephedrine in men with retrograde ejaculation.

    PubMed

    Shoshany, O; Abhyankar, N; Elyaguov, J; Niederberger, C

    2017-07-01

    The use of pseudoephedrine, an alpha agonist, for the treatment of retrograde ejaculation is well-known, however, there is no clear consensus from the literature regarding its efficacy and treatment protocol. We evaluated the efficacy of pseudoephedrine treatment in patients with retrograde ejaculation, utilizing a yet undescribed short-period treatment protocol. Twenty men were medically treated with pseudoephedrine for retrograde ejaculation between January 2010 and May 2016 (12 with complete retrograde ejaculation and 8 with partial retrograde ejaculation). All patients had a semen analysis and post-ejaculatory urinalysis before and after treatment. The treatment protocol consisted of 60 mg of pseudoephedrine every 6 h on the day before semen analysis and two more 60 mg doses on the day of the semen analysis. Diabetes was the most common etiology for complete retrograde ejaculation (60%), whereas an idiopathic cause was the most common etiology for partial retrograde ejaculation (82%). Of the 12 complete retrograde ejaculation patients treated with pseudoephedrine prior to semen analysis, 7 (58.3%) recovered spermatozoa in the antegrade ejaculate, with a mean total sperm count of 273.5 ± 172.5 million. Of the eight patients with partial retrograde ejaculation, five (62.5%) had a ≥50% increase in the antegrade total sperm count. In this group, the mean total sperm count increased from 26.9 ± 8.5 million before treatment to 84.2 ± 24.6 million after treatment, whereas the percentage of spermatozoa in the urine declined from 43.2 ± 9% to 17 ± 10%, respectively (both p < 0.05). Overall, in men with retrograde ejaculation treated with a pseudoephedrine regimen prior to ejaculation, some improvement in seminal parameters occurred in 14 (70%) patients, with 10 patients (38.5% of all patients) achieving antegrade total sperm counts over 39 million. © 2017 American Society of Andrology and European Academy of Andrology.

  11. Retrograde ejaculation after anterior lumbar spine surgery.

    PubMed

    Lindley, Emily M; McBeth, Zachary L; Henry, Sarah E; Cooley, Robert; Burger, Evalina L; Cain, Christopher M J; Patel, Vikas V

    2012-09-15

    A retrospective cohort study. To compare the incidence of retrograde ejaculation (RE) after anterior lumbar spine surgery with disc replacement versus fusion with the use of recombinant human bone morphogenetic protein-2 (BMP). Anterior lumbar interbody fusion (ALIF) has become a popular choice for treating a number of pathologies, largely because it preserves the posterior paravertebral muscles and ligaments. Despite these advantages, the anterior approach is also associated with various complications, one of which is RE. A recent study has questioned whether the risk of RE is increased by the use of BMP in ALIF procedures rather than by the approach alone. We conducted a retrospective review of all male patients who received ALIF using BMP or artificial disc replacement (ADR) on at least the L5-S1 level between 2004 and 2011. Medical records were evaluated for the occurrence of RE, and patients were contacted via the phone to obtain current information. The incidence of RE was then compared between the 2 anterior lumbar surgery procedures. Of the 95 cases of anterior surgery including L5-S1, 54 patients underwent ALIF with BMP (56.8%) and 41 patients were treated with ADR (43.2%). Postoperative RE occurred in 4 of the 54 ALIF patients (7.4%) and in 4 of the 41 ADR patients (9.8%). The incidence of RE was not significantly different between groups (P = 0.7226). At latest follow-up, 1 ALIF and 1 ADR patient reported resolution of the RE. This study found that RE occurred at a similar rate in patients treated with ADR and ALIF with BMP. The overall rate of RE after retroperitoneal anterior lumbar surgery was higher than expected, which underscores the importance of counseling patients about this risk and specifically questioning patients about the symptoms of RE at postoperative visits.

  12. Axoplasmic importins enable retrograde injury signaling in lesioned nerve.

    PubMed

    Hanz, Shlomit; Perlson, Eran; Willis, Dianna; Zheng, Jun-Qi; Massarwa, R'ada; Huerta, Juan J; Koltzenburg, Martin; Kohler, Matthias; van-Minnen, Jan; Twiss, Jeffery L; Fainzilber, Mike

    2003-12-18

    Axoplasmic proteins containing nuclear localization signals (NLS) signal retrogradely by an unknown mechanism in injured nerve. Here we demonstrate that the importin/karyopherin alpha and beta families underlie this process. We show that importins are found in axons at significant distances from the cell body and that importin beta protein is increased after nerve lesion by local translation of axonal mRNA. This leads to formation of a high-affinity NLS binding complex that traffics retrogradely with the motor protein dynein. Trituration of synthetic NLS peptide at the injury site of axotomized dorsal root ganglion (DRG) neurons delays their regenerative outgrowth, and NLS introduction to sciatic nerve concomitantly with a crush injury suppresses the conditioning lesion induced transition from arborizing to elongating growth in L4/L5 DRG neurons. These data suggest a model whereby lesion-induced upregulation of axonal importin beta may enable retrograde transport of signals that modulate the regeneration of injured neurons.

  13. Yarkovsky effect in the motion of asteroids in retrograde orbits

    NASA Astrophysics Data System (ADS)

    Kankiewicz, Paweł; Włodarczyk, Ireneusz

    2016-06-01

    Since the last few years, many small bodies in retrograde orbits was discovered, classified as asteroids. %Most of these orbits are located in peripherals of the Solar System. Main aim of our work is the analysis of their dynamical past and future. For 56 asteroids in retrograde orbits (i > 90) we studied the orbital evolution and calculated median dynamical lifetimes. Due to important role of the Yarkovsky effect in the motion of small bodies, we decided to apply the model with the Yarkovsky forces. Because the physical properties of these objects are still not well determined, we collected thermal parameters from literature or calculated from available formulas. The complete set of 'thermal' properties of each body is still not available from observational data, so our approach is a kind of approximation. Results obtained with these parameters allowed us to estimate the influence of the Yarkovsky effect on the stability of retrograde orbits.

  14. Retrograde resonance in the planar three-body problem

    NASA Astrophysics Data System (ADS)

    Morais, M. H. M.; Namouni, F.

    2013-12-01

    We continue the investigation of the dynamics of retrograde resonances initiated in Morais and Giuppone (Mon Notices R Astron Soc 424:52-64, doi:10.1111/j.1365-2966.2012.21151.x, 2012). After deriving a procedure to deduce the retrograde resonance terms from the standard expansion of the three-dimensional disturbing function, we concentrate on the planar problem and construct surfaces of section that explore phase-space in the vicinity of the main retrograde resonances (2/1, 1/1 and 1/2). In the case of the 1/1 resonance for which the standard expansion is not adequate to describe the dynamics, we develop a semi-analytic model based on numerical averaging of the unexpanded disturbing function, and show that the predicted libration modes are in agreement with the behavior seen in the surfaces of section.

  15. Fundamental studies of retrograde reactions in direct liquefaction

    SciTech Connect

    Serio, M.A.; Solomon, P.R.; Kroo, E.; Charpenay, S.; Bassilakis, R.

    1991-12-17

    The overall objective of the program was to improve the understanding of retrograde reactions and their dependencies on coal rank and structure, and/or coal modifications and reaction conditions. Because retrograde reactions are competitive with bond breaking reactions, an understanding of both is required to shift the competition in favor of the latter. Related objectives were to clarify the conflicting observations reported in literature on such major topics as the role of oxygen groups in retrograde reactions and to provide a bridge from very fundamental studies on pure compounds to phenomenological studies on actual coal. This information was integrated into the FG-DVC model, which was improved and extended to the liquefaction context.

  16. Dynein is the motor for retrograde axonal transport of organelles

    SciTech Connect

    Schnapp, B.J.; Reese, T.S.

    1989-03-01

    Vesicular organelles in axons of nerve cells are transported along microtubules either toward their plus ends (fast anterograde transport) or toward their minus ends (retrograde transport). Two microtubule-based motors were previously identified by examining plastic beads induced to move along microtubules by cytosol fractions from the squid giant axon: (i) an anterograde motor, kinesin, and (ii) a retrograde motor, which is characterized here. The retrograde motor, a cytosolic protein previously termed HMW1, was purified from optic lobes and extruded axoplasm by nucleotide-dependent microtubule affinity and release; microtubule gliding was used as the assay of motor activity. The following properties of the retrograde motor suggest that it is cytoplasmic dynein: (i) sedimentation at 20-22 S with a heavy chain of Mr greater than 200,000 that coelectrophoreses with the alpha and beta subunits of axonemal dynein, (ii) cleavage by UV irradiation in the presence of ATP and vanadate, and (iii) a molecular structure resembling two-headed dynein from axonemes. Furthermore, bead movement toward the minus end of microtubules was blocked when axoplasmic supernatants were treated with UV/vanadate. Treatment of axoplasmic supernatant with UV/vanadate also blocks the retrograde movement of purified organelles in vitro without changing the number of anterograde moving organelles, indicating that dynein interacts specifically with a subgroup of organelles programmed to move toward the cell body. However, purified optic lobe dynein, like purified kinesin, does not by itself promote the movement of purified organelles along microtubules, suggesting that additional axoplasmic factors are necessary for retrograde as well as anterograde transport.

  17. Retrograde tibial nail: anatomical implantation and surgical feasibility study.

    PubMed

    Kuhn, S; Appelmann, P; Pairon, P; Gruszka, D; Rommens, P M

    2015-01-01

    PURPOSE OF THE STUDY The treatment of distal tibial fractures requires a stable fixation while minimizing the secondary trauma to the soft tissues by the surgical approach and implant. The experimental Retrograde Tibial Nail is currently investigated as a minimally invasive alternative to plating and antegrade nailing. The purpose of this study was to evaluate the surgical feasibility in a cadaver model for all distal tibial fracture types generally considered treatable by nailing. MATERIAL AND METHODS Five different fracture types (AO/OTA 43-A1/A2/A3 and 43-C1/C2) were created on separate cadaveric limbs. In simple fractures (AO/OTA 43-A1/A2/A3) primary nailing was performed. In intraarticular fractures (AO/OTA 43-C1/2) reduction of the articular block and lag screw fixation was performed before nailing. Intraoperative complications, quality of reduction, fluoroscopy duration and operative time were evaluated. RESULTS Retrograde intramedullary nailing is feasible in simple fracture types by closed manual reduction and percutaneous reduction forceps. Retrograde nailing is possible in fractures with simple intraarticular involvement after primary lag screw fixation. The duration of surgery averaged 51.8 minutes (range 40-62 min). No major complications occurred during nailing. CONCLUSIONS The minimally invasive retrograde nail combines a minimally invasive local osteosynthesis with the ability to adequately fix extraarticular and simple intraarticular distal tibial fractures. The results suggests that retrograde tibia nailing is a promising new concept for the treatment of distal tibia fractures. Key words: minimally invasive surgery, tibia, metaphyseal fractures, intramedullary nailing, retrograde nailing.

  18. Orbital Evolution and Impact Hazard of Asteroids on Retrograde Orbits

    NASA Astrophysics Data System (ADS)

    Kankiewicz, P.; Włodarczyk, I.

    2014-07-01

    We present the past evolutional scenarios of known group of asteroids in retrograde orbits. Applying the latest observational data, we determined their nominal and averaged orbital elements. Next, we studied the behaviour of their orbital motion 1~My in the past (100~My in the future for two NEAs) taking into account the limitations of observational errors. It has been shown that the influence of outer planets perturbations in many cases can import small bodies on high inclination or retrograde orbits into the inner Solar System.

  19. Physiology and pathology of endosome-to-Golgi retrograde sorting.

    PubMed

    Burd, Christopher G

    2011-08-01

    Bidirectional traffic between the Golgi apparatus and the endosomal system sustains the functions of the trans-Golgi network (TGN) in secretion and organelle biogenesis. Export of cargo from the TGN via anterograde trafficking pathways depletes the organelle of sorting receptors, processing proteases, SNARE molecules, and other factors, and these are subsequently retrieved from endosomes via the retrograde pathway. Recent studies indicate that retrograde trafficking is vital to early metazoan development, nutrient homeostasis, and for processes that protect against Alzheimer's and other neurological diseases.

  20. [Subcapsular hepatic hematoma: an uncommon complication of endoscopic retrograde cholangiopancreatography].

    PubMed

    Baudet, Juan-Salvador; Arguiñarena, Xabier; Redondo, Ignacio; Tadeo, Eva; Navazo, Lucía; Mendiz, Javier; Montiel, Raquel

    2011-02-01

    This report describes the case of a patient who developed a subcapsular hepatic hematoma 48 hours after endoscopic retrograde cholangiopancreatography. She was treated by embolizing the sites of bleeding and by surgically resecting the area. We review the literature and discuss the potential mechanisms that cause this complication.

  1. Light intensity-dependent retrograde signalling in higher plants.

    PubMed

    Szechyńska-Hebda, Magdalena; Karpiński, Stanisław

    2013-11-15

    Plants are able to acclimate to highly fluctuating light environment and evolved a short- and long-term light acclimatory responses, that are dependent on chloroplasts retrograde signalling. In this review we summarise recent evidences suggesting that the chloroplasts act as key sensors of light intensity changes in a wide range (low, high and excess light conditions) as well as sensors of darkness. They also participate in transduction and synchronisation of systemic retrograde signalling in response to differential light exposure of distinct leaves. Regulation of intra- and inter-cellular chloroplast retrograde signalling is dependent on the developmental and functional stage of the plastids. Therefore, it is discussed in following subsections: firstly, chloroplast biogenic control of nuclear genes, for example, signals related to photosystems and pigment biogenesis during early plastid development; secondly, signals in the mature chloroplast induced by changes in photosynthetic electron transport, reactive oxygen species, hormones and metabolite biosynthesis; thirdly, chloroplast signalling during leaf senescence. Moreover, with a help of meta-analysis of multiple microarray experiments, we showed that the expression of the same set of genes is regulated specifically in particular types of signals and types of light conditions. Furthermore, we also highlight the alternative scenarios of the chloroplast retrograde signals transduction and coordination linked to the role of photo-electrochemical signalling. Copyright © 2013 Elsevier GmbH. All rights reserved.

  2. Selected properties of acetylated adipate of retrograded starch.

    PubMed

    Zięba, T; Gryszkin, A; Kapelko, M

    2014-01-01

    Native potato starch (NS) and retrograded starch (R - obtained via freezing and defrosting of a starch paste) were used to prepare starch acetates: NS-A and R-A, and then acetylated distarch adipates: NS-ADA and R-ADA. The chemically-modified preparations produced from retrograded starch (R-A; R-ADA) were characterized by a higher degree of esterification compared to the modified preparations produced under the same conditions from native potato starch (NS-A; NS-ADA). Starch resistance to amylolysis was observed to increase (to 30-40 g/100 g) as a result of starch retrogradation and acetylation. Starch cross-linking had a significant impact on the increased viscosity of the paste in the entire course of pasting characteristics and on the increased values of rheological coefficients determined from the equations describing flow curves. The produced preparation of acetylated retrograded starch cross-linked with adipic acid (R-ADA) may be deemed an RS3/4 preparation to be used as a food thickening agent.

  3. Water dynamics and retrogradation of ultrahigh pressurized wheat starch.

    PubMed

    Doona, Christopher J; Feeherry, Florence E; Baik, Moo-Yeol

    2006-09-06

    The water dynamics and retrogradation kinetics behavior of gelatinized wheat starch by either ultrahigh pressure (UHP) processing or heat are investigated. Wheat starch completely gelatinized in the condition of 90, 000 psi at 25 degrees C for 30 min (pressurized gel) or 100 degrees C for 30 min (heated gel). The physical properties of the wheat starches were characterized in terms of proton relaxation times (T2 times) measured using time-domain nuclear magnetic resonance spectroscopy and evaluated using commercially available continuous distribution modeling software. Different T2 distributions in both micro- and millisecond ranges between pressurized and heated wheat starch gels suggest distinctively different water dynamics between pressurized and heated wheat starch gels. Smaller water self-diffusion coefficients were observed for pressurized wheat starch gels and are indicative of more restricted translational proton mobility than is observed with heated wheat starch gels. The physical characteristics associated with changes taking place during retrogradation were evaluated using melting curves obtained with differential scanning calorimetry. Less retrogradation was observed in pressurized wheat starch, and it may be related to a smaller quantity of freezable water in pressurized wheat starch. Starches comprise a major constituent of many foods proposed for commercial potential using UHP, and the present results furnish insight into the effect of UHP on starch gelatinization and the mechanism of retrogradation during storage.

  4. The management of retrograde ejaculation: a systematic review and update.

    PubMed

    Jefferys, Amanda; Siassakos, Dimitrios; Wardle, Peter

    2012-02-01

    To determine the best management of retrograde ejaculation to optimize the chance of conception. Systematic review. Tertiary reproductive medicine center. Subfertile men with retrograde ejaculation. Systematic search of studies using search terms "management" or "therapy" or "treatment" and "retrograde ejaculation." We excluded case reports and papers not in English. Pregnancy and live birth rates and rates of achievement of antegrade ejaculation. Thirty-four studies met our criteria. Studies were mostly observational. Descriptions of predictive and confounding variables were often insufficient. The treatment options included urinary sperm retrieval and medical management with anticholinergics and sympathomimetics. Successful pregnancies and live births were also achieved using surgical techniques and electroejaculation; however, numbers were small. Many treatment options exist in the management of retrograde ejaculation; however, current literature is insufficient to allow firm comparisons between interventions. Treatment should be tailored, therefore, to the individual. Our findings support the need for further research in this area-including large randomized controlled trials. However, these would be difficult logistically and may not be possible. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. Chloroplast Retrograde Regulation of Heat Stress Responses in Plants

    PubMed Central

    Sun, Ai-Zhen; Guo, Fang-Qing

    2016-01-01

    It is well known that intracellular signaling from chloroplast to nucleus plays a vital role in stress responses to survive environmental perturbations. The chloroplasts were proposed as sensors to heat stress since components of the photosynthetic apparatus housed in the chloroplast are the major targets of thermal damage in plants. Thus, communicating subcellular perturbations to the nucleus is critical during exposure to extreme environmental conditions such as heat stress. By coordinating expression of stress specific nuclear genes essential for adaptive responses to hostile environment, plants optimize different cell functions and activate acclimation responses through retrograde signaling pathways. The efficient communication between plastids and the nucleus is highly required for such diverse metabolic and biosynthetic functions during adaptation processes to environmental stresses. In recent years, several putative retrograde signals released from plastids that regulate nuclear genes have been identified and signaling pathways have been proposed. In this review, we provide an update on retrograde signals derived from tetrapyrroles, carotenoids, reactive oxygen species (ROS) and organellar gene expression (OGE) in the context of heat stress responses and address their roles in retrograde regulation of heat-responsive gene expression, systemic acquired acclimation, and cellular coordination in plants. PMID:27066042

  6. Retrograde Oxygen Persufflation of Kidney - Experiment on an Animal.

    PubMed

    Moláček, Jiri; Opatrný, Václav; Matějka, Roman; Baxa, Jan; Třeška, Vladislav

    There is still a lack of organs for transplantation purposes. In the field of kidney and liver transplantation, one available solution is the use of organs from so-called marginal donors. These donors can be e.g. non-heart-beating donors. In these cases, perfusion and preservation of organs intended for transplantation is generally more difficult. Retrograde oxygen persufflation (ROP) may be a possible solution to this issue. This method is based on retrograde perfusion by oxygen through the renal vein thus reconditioning the organ. We operated on 10 animals (porcine models). Ischemic injury of the right kidney was simulated in all animals. In group A (N=5), kidneys were perfused with retrograde oxygen persufflation after explantation. In group B (N=5), kidneys were perfused intrarterially as in usual clinical practice. After perfusion all kidneys were transplanted to the original donor animal. Quality of graft restitution was evaluated by the urea level obtained from the renal vein and by histopathological analysis after explantation. We found no statistically significant differences between groups A and B in urea levels after transplantation, nor did we find any significant differences in quality of kidney parenchyma restoration between these groups. Retrograde oxygen persufflation is able to protect and restore kidney parenchyma. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  7. Analysis of retrograde ejaculation using color Doppler ultrasonography before and after transurethral collagen injection.

    PubMed

    Nagai, A; Nasu, Y; Watanabe, M; Tsugawa, M; Iguchi, H; Kumon, H

    2004-10-01

    Transurethral bladder neck collagen injection therapy was performed in a patient with retrograde ejaculation. The phenomenon of retrograde ejaculation and its correction after the therapy were clearly demonstrated by color Doppler ultrasonography. To our knowledge this is the first report showing successful observation of retrograde ejaculation using color Doppler ultrasonography.

  8. Retrograde fluids in granulites: Stable isotope evidence of fluid migration

    SciTech Connect

    Morrison, J. ); Valley, J.W. )

    1991-07-01

    Widespread retrograde alteration assemblages document the migration of mixed H{sub 2}O-CO{sub 2} fluids into granulite facies rocks in the Adirondack Mountains. Fluid migration is manifest by (1) veins and patchy intergrowths of chlorite {plus minus} sericite {plus minus} calcite, (2) small veins of calcite, many only identifiable by cathodoluminescence, and (3) high-density, CO{sub 2}-rich or mixed H{sub 2}O-CO{sub 2} fluid inclusions. The distinct and varied textural occurrences of the alteration minerals indicate that fluid-rock ratios were low and variable on a local scale. Stable isotope ratios of C, O, and S have been determined in retrograde minerals from samples of the Marcy anorthosite massif and adjacent granitic gneisses (charnockites). Retrograde calcite in the anorthosite has a relatively small range in both {delta}{sup 18}O{sub SMOW} and {delta}{sup 13}C{sub PDB} (8.6 to 14.9% and {minus}4.1 to 0.4%, respectively), probably indicating that the hydrothermal fluids that precipitated the calcite had exchanged with a variety of crustal lithologies including marbles and orthogneisses, and that calcite was precipitated over a relatively narrow temperature interval. Values of {delta}{sup 34}S{sub CDT} that range from 2.8 to 8.3% within the anorthosite can also be interpreted to reflect exchange between orthogneisses and metasediments. The recognition of retrograde fluid migration is particularly significant in granulite facies terranes because the controversy surrounding the origin of granulites arises in part from differing interpretations of fluid inclusion data, specifically, the timing of entrapment of high-density, CO{sub 2}-rich inclusions. Results indicate that retrograde fluid migration, which in some samples may leave only cryptic petrographic evidence, is a process capable of producing high-density, CO{sub 2}-rich fluid inclusions.

  9. Retrograde traffic in the biosynthetic-secretory route

    PubMed Central

    Neumüller, Josef; Ellinger, Adolf

    2008-01-01

    In the biosynthetic-secretory route from the rough endoplasmic reticulum, across the pre-Golgi intermediate compartments, the Golgi apparatus stacks, trans Golgi network, and post-Golgi organelles, anterograde transport is accompanied and counterbalanced by retrograde traffic of both membranes and contents. In the physiologic dynamics of cells, retrograde flow is necessary for retrieval of molecules that escaped from their compartments of function, for keeping the compartments’ balances, and maintenance of the functional integrities of organelles and compartments along the secretory route, for repeated use of molecules, and molecule repair. Internalized molecules may be transported in retrograde direction along certain sections of the secretory route, and compartments and machineries of the secretory pathway may be misused by toxins. An important example is the toxin of Shigella dysenteriae, which has been shown to travel from the cell surface across endosomes, and the Golgi apparatus en route to the endoplasmic reticulum, and the cytosol, where it exerts its deleterious effects. Most importantly in medical research, knowledge about the retrograde cellular pathways is increasingly being utilized for the development of strategies for targeted delivery of drugs to the interior of cells. Multiple details about the molecular transport machineries involved in retrograde traffic are known; a high number of the molecular constituents have been characterized, and the complicated fine structural architectures of the compartments involved become more and more visible. However, multiple contradictions exist, and already established traffic models again are in question by contradictory results obtained with diverse cell systems, and/or different techniques. Additional problems arise by the fact that the conditions used in the experimental protocols frequently do not reflect the physiologic situations of the cells. Regular and pathologic situations often are intermingled, and

  10. Predisposing conditions for retrograde peri-implantitis, and treatment suggestions.

    PubMed

    Quirynen, Marc; Vogels, Roel; Alsaadi, Ghada; Naert, Ignace; Jacobs, Reinhilde; van Steenberghe, Daniel

    2005-10-01

    Recent case reports introduced the term retrograde peri-implantitis as a lesion (radiolucency) around the most apical part of an osseointegrated implant. It develops within the first months after insertion. This retrospective study aimed to find predisposing conditions for such peri-apical lesions and to evaluate treatment strategies. All single implants (426 in the upper, 113 in the lower jaw, all Brånemark system type) placed at the department of Periodontology of the University Hospital (Catholic University Leuven) were included in this retrospective evaluation to check the incidence of retrograde peri-implantitis. Eventual predisposing factors such as patient characteristics (age, medical history), recipient site (local bone quality and quantity, cause of tooth loss), periodontal and endodontic conditions of neighboring teeth, implant characteristics (length, surface characteristics), and surgical aspects (guided bone regeneration, osseous fenestration, or dehiscency) were considered. Moreover, implants with retrograde peri-implantitis were followed longitudinally to verify their treatment outcome by means of different parameters (Periotest values (PTV), marginal bone level, radiological size of peri-apical defect). Seven implants in the upper (1.6%) and 3 in the lower jaw (2.7%) showed retrograde peri-implantitis, before or at abutment connection. In comparison with successful implants, such peri-apical lesions occurred preferably at sites with a history of an obvious endodontic pathology of the extracted tooth to be replaced. The incidence of retrograde peri-implantitis was significantly higher (P<0.0001) for TiUnite implants when compared with the machined implants (8/80 vs. 2/459). The machined implant surface, however, showed a higher failure rate (6.8%) than the TiUnite implants (2.5%). Failures with machined surfaces preferably occurred at extraction sites of teeth with a history of endodontic pathology or sites adjacent to teeth with an obvious

  11. Effects of inulin with different degree of polymerization on gelatinization and retrogradation of wheat starch.

    PubMed

    Luo, Denglin; Li, Yun; Xu, Baocheng; Ren, Guangyue; Li, Peiyan; Li, Xuan; Han, Sihai; Liu, Jianxue

    2017-08-15

    The effects of three types of inulin, including FS (DP≤10), FI (DP of 2-60) and FXL (DP≥23), on the gelatinization and retrogradation characteristics of wheat starch were investigated. As the concentration of inulin added into starch increased, the gelatinization temperature increased whereas the breakdown value decreased, and the value of setback first decreased and then increased slightly. The three types of inulin with lower concentrations (<15%) all showed obvious suppression effects on the short-term retrogradation of wheat starch. After 7days of storage, the three types of inulin showed a significant suppression of starch retrogradation in the addition range of 5-7.5%. They can all inhibit amylose retrogradation, but accelerate amylopectin retrogradation. Inulin with lower DP has stronger effects on the starch retrogradation. Generally, the three types of inulin can all retard the retrogradation performance of wheat starch to some extent in the long-term storage. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Effects of chitin nano-whiskers on the gelatinization and retrogradation of maize and potato starches.

    PubMed

    Ji, Na; Liu, Chengzhen; Zhang, Shuangling; Yu, Jing; Xiong, Liu; Sun, Qingjie

    2017-01-01

    Starch is very prone to retrogradation after gelatinization. Inhibition of starch retrogradation has been an important factor in improving the quality of food. For the first time, we investigated the effect of nano-materials, represented by chitin nano-whiskers (CNWs), on the short- and long-term retrogradation of maize and potato starches. Rapid Visco-Analyser results showed that the addition of CNWs significantly decreased the setback values of maize and potato starches, which suggested that CNWs could retard the short-term retrogradation of starch. Differential scanning calorimetry and X-ray diffraction results showed that the percentage of retrogradation of maize and potato starches significantly decreased (P<0.05), suggesting the inhibition of long-term retrogradation. The CNWs could be used as a new inhibitor of starch retrogradation to develop starch-based food with longer shelf life. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Retrograde amnesia following carbon monoxide poisoning: a case report.

    PubMed

    Acland, Peter R; Heaver, Catriona

    2008-07-01

    Retrograde amnesia is a recognised neurological complication of carbon monoxide poisoning. This article describes the case of a female found dead in her bath where initial post-mortem findings and the surrounding circumstances raised strong suspicions of homicide, especially when there was contradictory evidence from her husband who was the only other person present. He was later diagnosed as having retrograde amnesia between his two visits to the bathroom to attend to his wife which caused him to merge them into one event, thus arousing suspicions of foul play. The discussion explores the current clinical views on non-fatal carbon monoxide poisoning as well as problems of interpretation of information derived from case work.

  14. Photosynthetic light reactions: integral to chloroplast retrograde signalling.

    PubMed

    Gollan, Peter J; Tikkanen, Mikko; Aro, Eva-Mari

    2015-10-01

    Chloroplast retrograde signalling is ultimately dependent on the function of the photosynthetic light reactions and not only guides the acclimation of the photosynthetic apparatus to changing environmental and metabolic cues, but has a much wider influence on the growth and development of plants. New information generated during the past few years about regulation of photosynthetic light reactions and identification of the underlying regulatory proteins has paved the way towards better understanding of the signalling molecules produced in chloroplasts upon changes in the environment. Likewise, the availability of various mutants lacking regulatory functions has made it possible to address the role of excitation energy distribution and electron flow in the thylakoid membrane in inducing the retrograde signals from chloroplasts to the nucleus. Such signalling molecules also induce and interact with hormonal signalling cascades to provide comprehensive information from chloroplasts to the nucleus.

  15. WLS retrograde transport to the endoplasmic reticulum during Wnt secretion.

    PubMed

    Yu, Jia; Chia, Joanne; Canning, Claire Ann; Jones, C Michael; Bard, Frédéric A; Virshup, David M

    2014-05-12

    Wnts are transported to the cell surface by the integral membrane protein WLS (also known as Wntless, Evi, and GPR177). Previous studies of WLS trafficking have emphasized WLS movement from the Golgi to the plasma membrane (PM) and then back to the Golgi via retromer-mediated endocytic recycling. We find that endogenous WLS binds Wnts in the endoplasmic reticulum (ER), cycles to the PM, and then returns to the ER through the Golgi. We identify an ER-targeting sequence at the carboxyl terminus of native WLS that is critical for ER retrograde recycling and contributes to Wnt secretory function. Golgi-to-ER recycling of WLS requires the COPI regulator ARF as well as ERGIC2, an ER-Golgi intermediate compartment protein that is also required for the retrograde trafficking of the KDEL receptor and certain toxins. ERGIC2 is required for efficient Wnt secretion. ER retrieval is an integral part of the WLS transport cycle.

  16. Retrograde Lacrimal Duct Airflow During Nasal Positive Pressure Ventilation

    PubMed Central

    Zandieh, Stephanie; Katz, Eliot S.

    2010-01-01

    Noninvasive ventilation is widely used for chronic respiratory failure in children with neuromuscular disorders, thus avoiding the need for tracheostomy. However, the pressures required to support ventilation in these children may be considerably higher than those necessary to treat obstructive sleep apnea. The complications of nasal positive airway pressure are numerous, including skin breakdown, conjunctivitis, nasal congestion, airway dryness, pneumothorax, and bowel obstruction. Ophthalmologic complaints are particularly common, largely attributed to an air leak in the mask. In the present case, we demonstrate, through two modalities—video and CT scan—retrograde airflow through the nasolacrimal duct causing sleep disruption and eye irritation in a profoundly hypotonic 14-month-old boy with chronic respiratory failure on bilevel ventilation during sleep. Citation: Zandieh S; Katz ES. Retrograde lacrimal duct airflow during nasal positive pressure ventilation. J Clin Sleep Med 2010;6(6):603-604. PMID:21206550

  17. Retrograde amnesia induced by drugs acting on different molecular systems.

    PubMed

    Rossato, Janine I; Bonini, Juliana S; Coitinho, Adriana S; Vianna, Monica R M; Medina, Jorge H; Cammarota, Martín; Izquierdo, Iván

    2004-06-01

    The gamma aminobutyric acid-A (GABA-sub(A)) agonist, muscimol, the glutamate N-methyl-D-aspartate (NMDA) receptor antagonist, D-2-amino-5-phosphonopentanoic acid (AP5), and the inhibitor of the extracellularly regulated kinases (ERKs), UO 126, cause retrograde amnesia when administered to the hippocampus. In the present study, the authors found that they all cause retrograde amnesia for 1-trial inhibitory avoidance, not only when infused into the dorsal CA1 region of the hippocampus, but also when infused into the basolateral amygdala or the entorhinal, parietal, and posterior cingulate cortices. The posttraining time course of the effect of each drug was, however, quite different across brain structures. Thus, in all of them, NMDA receptors and the ERK pathway are indispensable for memory consolidation, and GABA-sub(A) receptor activation inhibits memory consolidation: but in each case, their influence is interwoven differently.

  18. The Management of Retrograde Peri-Implantitis: A Case Report

    PubMed Central

    Mohamed, Jumshad B; Alam, Md Nazish; Singh, Gurudeep; Chandrasekaran, S. C.

    2012-01-01

    Peri-Implantitis is defined as an inflammatory reaction with the loss of the supporting bone in the tissues which surround a functioning implant. The peri-implantitis lesions are often asymptomatic and they are usually detected during the routine recall appointments. Careful probing around the teeth and the implants should be done routinely along with the radiologic evaluation during these check-up appointments. Retrograde peri-implantitis may sometimes prove even more difficult to identify, resulting in the loss of the implant. This paper presents a report of the extensive and the meticulous management of retrograde peri-implantitis and the implant being finally restored to health and the full functional status. PMID:23285472

  19. Ureteroscopy-Assisted Retrograde Nephrostomy (UARN) after Anatrophic Nephrolithotomy.

    PubMed

    Kawahara, Takashi; Ito, Hiroki; Terao, Hideyuki; Kato, Yoshitake; Ogawa, Takehiko; Uemura, Hiroji; Kubota, Yoshinobu; Matsuzaki, Junichi

    2012-01-01

    Introduction. Open surgical anatrophic nephrolithotomy (ANL) had been the standard treatment for large renal calculi prior to the development of endoscopic devices and endoscopic techniques. A previous report described the efficacy of ureteroscopy-assisted retrograde nephrostomy (UARN) and presented a case of renal calculi successfully treated with UARN during percutaneous nephrolithotomy (PCNL) in a patient after ANL. Case Presentation. A 61-year-old male with left renal calculi was referred for further treatment. The patient was placed under general and epidural anesthesia, in a Galdakao-modified Valdivia position. A flexible ureteroscope (URS) was inserted, and a Lawson retrograde nephrostomy puncture wire was advanced into the flexible URS. The puncture wire then followed the route from the renal pelvis to the exit skin. Calculus fragmentation was undertaken using a pneumatic lithotripter. Conclusions. UARN for PCNL was therefore found to be a safe, effective, and appropriate treatment for a patient presenting with renal calculi after undergoing ANL.

  20. Ureteroscopy assisted retrograde nephrostomy for complete staghorn renal calculi.

    PubMed

    Kawahara, Takashi; Ito, Hiroki; Terao, Hideyuki; Ogawa, Takehiko; Uemura, Hiroji; Kubota, Yoshinobu; Matsuzaki, Junichi

    2012-09-01

    Complete staghorn calculi are typically managed with percutaneous nephrolithotomy (PCNL). However, dilating nephrostomy and inserting a nephro access sheath can be difficult to perform without hydronephrosis. We reported the procedure of ureteroscopy-assisted retrograde nephrostomy (UARN) during PCNL. UARN is effective without dilating the renal collecting system in cases of complete staghorn calculi. A 63-year old female with a left complete staghorn renal calculus was referred to our hospital. Under general and epidural anesthesia, the patient was placed in a modified-Valdivia position. A flexible ureteroscope was inserted and a Lawson retrograde nephrostomy puncture wire was advanced into the flexible ureteroscope. The puncture wire was forwarded along the route from the renal pelvis to the exit skin. Calculus fragmentation was done using a pneumatic lithotripter and the Ho: YAG laser. UARN during PCNL was effective for the treatment of a complete staghorn calculus.

  1. Ureteroscopy Assisted Retrograde Nephrostomy for Complete Staghorn Renal Calculi

    PubMed Central

    Kawahara, Takashi; Ito, Hiroki; Terao, Hideyuki; Ogawa, Takehiko; Uemura, Hiroji; Kubota, Yoshinobu; Matsuzaki, Junichi

    2012-01-01

    Complete staghorn calculi are typically managed with percutaneous nephrolithotomy (PCNL). However, dilating nephrostomy and inserting a nephro access sheath can be difficult to perform without hydronephrosis. We reported the procedure of ureteroscopy-assisted retrograde nephrostomy (UARN) during PCNL. UARN is effective without dilating the renal collecting system in cases of complete staghorn calculi. A 63-year old female with a left complete staghorn renal calculus was referred to our hospital. Under general and epidural anesthesia, the patient was placed in a modified-Valdivia position. A flexible ureteroscope was inserted and a Lawson retrograde nephrostomy puncture wire was advanced into the flexible ureteroscope. The puncture wire was forwarded along the route from the renal pelvis to the exit skin. Calculus fragmentation was done using a pneumatic lithotripter and the Ho: YAG laser. UARN during PCNL was effective for the treatment of a complete staghorn calculus. PMID:24917723

  2. Ureteroscopy-Assisted Retrograde Nephrostomy (UARN) after Anatrophic Nephrolithotomy

    PubMed Central

    Kawahara, Takashi; Ito, Hiroki; Terao, Hideyuki; Kato, Yoshitake; Ogawa, Takehiko; Uemura, Hiroji; Kubota, Yoshinobu; Matsuzaki, Junichi

    2012-01-01

    Introduction. Open surgical anatrophic nephrolithotomy (ANL) had been the standard treatment for large renal calculi prior to the development of endoscopic devices and endoscopic techniques. A previous report described the efficacy of ureteroscopy-assisted retrograde nephrostomy (UARN) and presented a case of renal calculi successfully treated with UARN during percutaneous nephrolithotomy (PCNL) in a patient after ANL. Case Presentation. A 61-year-old male with left renal calculi was referred for further treatment. The patient was placed under general and epidural anesthesia, in a Galdakao-modified Valdivia position. A flexible ureteroscope (URS) was inserted, and a Lawson retrograde nephrostomy puncture wire was advanced into the flexible URS. The puncture wire then followed the route from the renal pelvis to the exit skin. Calculus fragmentation was undertaken using a pneumatic lithotripter. Conclusions. UARN for PCNL was therefore found to be a safe, effective, and appropriate treatment for a patient presenting with renal calculi after undergoing ANL. PMID:22924043

  3. Retrograde trafficking of AB₅ toxins: mechanisms to therapeutics.

    PubMed

    Mukhopadhyay, Somshuvra; Linstedt, Adam D

    2013-10-01

    Bacterial AB5 toxins are a clinically relevant class of exotoxins that include several well-known members such as Shiga, cholera, and pertussis toxins. Infections with toxin-producing bacteria cause devastating human diseases that affect millions of individuals each year and have no definitive medical treatment. The molecular targets of AB5 toxins reside in the cytosol of infected cells, and the toxins reach the cytosol by trafficking through the retrograde membrane transport pathway that avoids degradative late endosomes and lysosomes. Focusing on Shiga toxin as the archetype member, we review recent advances in understanding the molecular mechanisms involved in the retrograde trafficking of AB5 toxins and highlight how these basic science advances are leading to the development of a promising new therapeutic approach based on inhibiting toxin transport.

  4. Clinical application of the retrograde arterialized venous flap.

    PubMed

    Koch, Horst; Scharnagl, Erwin; Schwarzl, Franz X; Haas, Franz M; Hubmer, Martin; Moshammer, Harald E T

    2004-01-01

    Retrograde arterialized venous flaps were applied to skin and soft-tissue defects in 13 patients with an average age of 34.4 years. Ten defects were located on the hand, and three on the lower leg. All flaps were harvested from the flexor aspect of the forearm; they ranged in size from 2 x 1 to 11 x 7 cm. There was venous congestion with superficial epidermolysis in six flaps, but not in the other seven. Partial skin necrosis in two of the lower-extremity flaps necessitated secondary skin grafts. Our results suggest that retrograde perfusion enhances blood flow in the periphery of arterialized venous flaps and gives good results in terms of flap survival, especially on the upper extremity. Copyright 2004 Wiley-Liss, Inc.

  5. TRANSIT TIMING VARIATIONS FOR INCLINED AND RETROGRADE EXOPLANETARY SYSTEMS

    SciTech Connect

    Payne, Matthew J.; Ford, Eric B.; Veras, Dimitri

    2010-03-20

    We perform numerical calculations of the expected transit timing variations (TTVs) induced on a hot-Jupiter by an Earth-mass perturber. Motivated by the recent discoveries of retrograde transiting planets, we concentrate on an investigation of the effect of varying relative planetary inclinations, up to and including completely retrograde systems. We find that planets in low-order (e.g., 2:1) mean-motion resonances (MMRs) retain approximately constant TTV amplitudes for 0 deg. < i < 170 deg., only reducing in amplitude for i>170 deg. Systems in higher order MMRs (e.g., 5:1) increase in TTV amplitude as inclinations increase toward 45 deg., becoming approximately constant for 45 deg. < i < 135 deg., and then declining for i>135 deg. Planets away from resonance slowly decrease in TTV amplitude as inclinations increase from 0 deg. to 180 deg., whereas planets adjacent to resonances can exhibit a huge range of variability in TTV amplitude as a function of both eccentricity and inclination. For highly retrograde systems (135 deg. < i {<=} 180 deg.), TTV signals will be undetectable across almost the entirety of parameter space, with the exceptions occurring when the perturber has high eccentricity or is very close to an MMR. This high inclination decrease in TTV amplitude (on and away from resonance) is important for the analysis of the known retrograde and multi-planet transiting systems, as inclination effects need to be considered if TTVs are to be used to exclude the presence of any putative planetary companions: absence of evidence is not evidence of absence.

  6. Propofol use in endoscopic retrograde cholangiopancreatography and endoscopic ultrasound

    PubMed Central

    Cheriyan, Danny G; Byrne, Michael F

    2014-01-01

    Compared to standard endoscopy, endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) are often lengthier and more complex, thus requiring higher doses of sedatives for patient comfort and compliance. The aim of this review is to provide the reader with information regarding the use, safety profile, and merits of propofol for sedation in advanced endoscopic procedures like ERCP and EUS, based on the current literature. PMID:24833847

  7. Formation Flying in Earth, Libration, and Distant Retrograde Orbits

    NASA Technical Reports Server (NTRS)

    Folta, David C.

    2004-01-01

    This slide presentation examines the current and future state of formation flying, LEO formations, control strategies for flight in the vicinity of the libration points, and distant retrograde orbit formations. This discussion of LEO formations includes background on perturbation theory/accelerations and LEO formation flying. The discussion of strategies for formation flight in the vicinity of the libration points includes libration missions and natural and controlled libration orbit formations. A reference list is included.

  8. Life threatening hemobilia after endoscopic retrograde cholangiopancreatography (ERCP).

    PubMed

    El Hajj, Ihab I; Sherman, Stuart; Pyko, Maximilian; Lehman, Glen A

    2017-09-11

    Arterial vascular complication from endoscopic retrograde cholangiopancreatography (ERCP) is exceedingly rare. This report describes a life threatening hemobilia, from a pseudoaneurysm of the right hepatic artery (RHA), which occurred post ERCP. The pseudoaneurysm and the active bleed were diagnosed by selective angiography of the RHA, and successfully treated with stenting. Copyright © 2017 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  9. Side Effects of alpha-Blocker Use: Retrograde Ejaculation.

    PubMed

    Kaplan, Steven A

    2009-01-01

    There are currently 5 alpha-blockers that are approved by the US Food and Drug Administration to treat lower urinary tract symptoms (LUTS). The American Urological Association guidelines committee believes that all alpha-blockers are equally effective. However, alpha-blockers differ in their likelihood of causing abnormal ejaculation. This article discusses the effects on ejaculatory function, and specifically retrograde ejaculation, of the currently available alpha-blockers being used to treat men with LUTS due to benign prostatic hyperplasia.

  10. Laparoscopic transgastric endoscopic retrograde cholangiopancreatography after biliopancreatic diversion.

    PubMed

    Molina Romero, Francesc Xavier; Morón Canis, José Miguel; Llompart Rigo, Alfredo; Rodríguez Pino, José Carlos; Morales Soriano, Rafael; González Argente, Francesc Xavier

    2015-11-01

    Endoscopic retrograde cholangiopancreatography may be difficult in patients that have undergone Roux-en-Y gastric bypass. Due to the fact that prevalence of morbid obesity is increasing, and laparoscopic procedures for its treatment have increased, the incidence of biliary tract problems in patients of altered anatomy is also growing. We describe a laparoscopic technique to access the biliary tree by endoscope, through the excluded stomach.

  11. A retrograde co-orbital asteroid of Jupiter.

    PubMed

    Wiegert, Paul; Connors, Martin; Veillet, Christian

    2017-03-29

    Recent theoretical work in celestial mechanics has revealed that an asteroid may orbit stably in the same region as a planet, despite revolving around the Sun in the sense opposite to that of the planet itself. Asteroid 2015 BZ509 was discovered in 2015, but with too much uncertainty in its measured orbit to establish whether it was such a retrograde co-orbital body. Here we report observations and analysis that demonstrates that asteroid 2015 BZ509 is indeed a retrograde co-orbital asteroid of the planet Jupiter. We find that 2015 BZ509 has long-term stability, having been in its current, resonant state for around a million years. This is long enough to preclude precise calculation of the time or mechanism of its injection to its present state, but it may be a Halley-family comet that entered the resonance through an interaction with Saturn. Retrograde co-orbital asteroids of Jupiter and other planets may be more common than previously expected.

  12. A retrograde co-orbital asteroid of Jupiter

    NASA Astrophysics Data System (ADS)

    Wiegert, Paul; Connors, Martin; Veillet, Christian

    2017-03-01

    Recent theoretical work in celestial mechanics has revealed that an asteroid may orbit stably in the same region as a planet, despite revolving around the Sun in the sense opposite to that of the planet itself. Asteroid 2015 BZ509 was discovered in 2015, but with too much uncertainty in its measured orbit to establish whether it was such a retrograde co-orbital body. Here we report observations and analysis that demonstrates that asteroid 2015 BZ509 is indeed a retrograde co-orbital asteroid of the planet Jupiter. We find that 2015 BZ509 has long-term stability, having been in its current, resonant state for around a million years. This is long enough to preclude precise calculation of the time or mechanism of its injection to its present state, but it may be a Halley-family comet that entered the resonance through an interaction with Saturn. Retrograde co-orbital asteroids of Jupiter and other planets may be more common than previously expected.

  13. Huge biloma after endoscopic retrograde cholangiopancreatography and endoscopic biliary sphincterotomy

    PubMed Central

    Alkhateeb, Harith M.; Aljanabi, Thaer J.; Al-azzawi, Khairallh H.; Alkarboly, Taha A.

    2015-01-01

    Background Biliary leak can occur as a complication of biliary surgery, endoscopic retrograde cholangiopancreatography manipulations and endoscopic biliary sphincterotomy. Consequently, bile may collect in the abdominal cavity, a condition called biloma. Rarely, it may reach a massive size. Case presentation A 72-year-old man presented with gastric upset with gradual abdominal distension reaching a large size due to intra-abdominal bile collection (biloma) after endoscopic retrograde cholangiopancreatography plus endoscopic biliary sphincterotomy and stenting for post laparoscopic cholecystectomy common bile duct stricture. This huge biloma was treated by percutaneous insertion of a tube drain for a few days, evacuating the collection successfully without recurrence. Discussion This patient might sustain injury to the common bile duct either by the guide wire or stent, or the injury occurred at the angle between the common bile duct and duodenum during sphincterotomy of the ampulla. Although any of these rents may lead to a bile leak, causing a huge biloma, they could be successfully treated by percutaneous drainage. Conclusions (1) Following endoscopic retrograde cholangiopancreatography, a patient’s complaints should not be ignored. (2) A massive biloma can occur due to such procedures. (3) Conservative treatment with minimal invasive technique can prove to be effective. PMID:26402876

  14. Osteochondritis Dissecans Involving the Trochlear Groove Treated With Retrograde Drilling

    PubMed Central

    Kaji, Yoshio; Nakamura, Osamu; Yamaguchi, Konosuke; Yamamoto, Tetsuji

    2015-01-01

    Abstract Osteochondritis dissecans (OCD) occurs frequently in the humeral capitellum of the upper extremity, whereas OCD involving the trochlear groove (trochlear groove OCD) is rarely reported. A standard treatment for trochlear groove OCD has therefore not been determined, although several methods have been tried. The case of a 14-year-old male gymnast with bilateral trochlear groove OCD is presented. Retrograde drilling from the lateral condyle of the humerus was applied for the OCD lesion of the left elbow, since it was larger in size than that in the right elbow and was symptomatic. Conversely, since the right lesion was small and asymptomatic, it was managed conservatively. After treatment, consolidation of the OCD lesions was observed in both elbows. However, the time to healing was shorter in the left elbow treated surgically than in the right elbow managed conservatively. In conclusion, retrograde drilling is a very simple and minimally invasive treatment. This case suggests that retrograde drilling for trochlear groove OCD may be a useful procedure that may accelerate the healing process for OCD lesions. PMID:26356703

  15. Novel Class of Potential Therapeutics that Target Ricin Retrograde Translocation

    PubMed Central

    Redmann, Veronika; Gardner, Thomas; Lau, Zerlina; Morohashi, Keita; Felsenfeld, Dan; Tortorella, Domenico

    2013-01-01

    Ricin toxin, an A-B toxin from Ricinus communis, induces cell death through the inhibition of protein synthesis. The toxin binds to the cell surface via its B chain (RTB) followed by its retrograde trafficking through intracellular compartments to the ER where the A chain (RTA) is transported across the membrane and into the cytosol. Ricin A chain is transported across the ER membrane utilizing cellular proteins involved in the disposal of aberrant ER proteins by a process referred to as retrograde translocation. Given the current lack of therapeutics against ricin intoxication, we developed a high-content screen using an enzymatically attenuated RTA chimera engineered with a carboxy-terminal enhanced green fluorescent protein (RTAE177Qegfp) to identify compounds that target RTA retrograde translocation. Stabilizing RTAE177Qegfp through the inclusion of proteasome inhibitor produced fluorescent peri-nuclear granules. Quantitative analysis of the fluorescent granules provided the basis to discover compounds from a small chemical library (2080 compounds) with known bioactive properties. Strikingly, the screen found compounds that stabilized RTA molecules within the cell and several compounds limited the ability of wild type RTA to suppress protein synthesis. Collectively, a robust high-content screen was developed to discover novel compounds that stabilize intracellular ricin and limit ricin intoxication. PMID:24366208

  16. Novel class of potential therapeutics that target ricin retrograde translocation.

    PubMed

    Redmann, Veronika; Gardner, Thomas; Lau, Zerlina; Morohashi, Keita; Felsenfeld, Dan; Tortorella, Domenico

    2013-12-23

    Ricin toxin, an A-B toxin from Ricinus communis, induces cell death through the inhibition of protein synthesis. The toxin binds to the cell surface via its B chain (RTB) followed by its retrograde trafficking through intracellular compartments to the ER where the A chain (RTA) is transported across the membrane and into the cytosol. Ricin A chain is transported across the ER membrane utilizing cellular proteins involved in the disposal of aberrant ER proteins by a process referred to as retrograde translocation. Given the current lack of therapeutics against ricin intoxication, we developed a high-content screen using an enzymatically attenuated RTA chimera engineered with a carboxy-terminal enhanced green fluorescent protein (RTA(E177Q)egfp) to identify compounds that target RTA retrograde translocation. Stabilizing RTA(E177Q)egfp through the inclusion of proteasome inhibitor produced fluorescent peri-nuclear granules. Quantitative analysis of the fluorescent granules provided the basis to discover compounds from a small chemical library (2080 compounds) with known bioactive properties. Strikingly, the screen found compounds that stabilized RTA molecules within the cell and several compounds limited the ability of wild type RTA to suppress protein synthesis. Collectively, a robust high-content screen was developed to discover novel compounds that stabilize intracellular ricin and limit ricin intoxication.

  17. The "Lantern" Procedure to Simplify Treatment of Retrograde Type A Dissection After Thoracic Endograft Stenting.

    PubMed

    Tsai, Chung-Lin

    2016-04-01

    The emergency repair of retrograde type A aortic dissection after thoracic endovascular aortic repair is a complex and challenging surgical procedure and carries a surgical challenge. Previous studies have reported a significant mortality in the complex repair of retrograde type A aortic dissection after thoracic endovascular aortic repair. We devised a simplified hybrid method-the "Lantern" procedure-to solve this retrograde type A aortic dissection complication.

  18. Intermittent rate-dependent retrograde conduction over a concealed atrioventricular accessory pathway: what is the mechanism?

    PubMed

    Rordorf, Roberto; Vicentini, Alessandro; Petracci, Barbara; Landolina, Maurizio

    2009-02-01

    Intermittent retrograde conduction over an accessory pathway (AP) is quite an uncommon phenomenon. We describe the case of a 60-year-old woman with recurrent episodes of palpitations. Atrioventricular re-entry tachycardia was diagnosed at electrophysiological study. Interestingly, retrograde conduction over the AP was detectable only when ventricular pacing was performed at fast rate. Supernormal retrograde conduction over the AP was considered the most likely explanation of this unusual finding.

  19. Successful rescue of a perforated chronic total occlusion using retrograde technique.

    PubMed

    Nah, Jong Chun; Cho, Wook Hyun; Choi, Suk Koo

    2009-06-01

    Percutaneous coronary intervention of chronic total occlusion (CTO) is one of the greatest challenges in coronary interventions. Retrograde wiring is suggested as a solution to improve the success rate of intervention for CTO. We experienced the coronary perforation during antegrade wiring at the CTO lesion and sealed it using retrograde wiring and antegrade stenting in a patient who underwent coronary arterial bypass grafting. We found that, in selected cases, the retrograde wire technique may provide a valuable rescue option for perforated CTO in a patient having a retrogradely accessible conduit vessel.

  20. Changing Strategies of the Retrograde Approach for Chronic Total Occlusion During the Past 7 Years

    PubMed Central

    Muramatsu, Toshiya; Tsukahara, Reiko; Ito, Yoshiaki; Ishimori, Hiroshi; Park, Seung-Jung; Winter, Robert; Shokry, Khaled; Wang, Lefeng; Chen, Jiyan; Wang, Haichang

    2013-01-01

    Objective We reviewed the technical changes and results achieved with the retrograde approach since we introduced it 7 years ago. Subjects and Methods The subjects were 1,268 patients who were treated for CTO between January 2004 and December 2010. They were investigated with respect to the success rate, the frequency of employing the retrograde approach and its outcome, and other factors. Results The retrograde approach was employed in ∼30% of chronic total occlusion (CTO) patients (n = 281) and the retrograde guidewire success rate was 81.1%. The kissing wire technique was substituted for the retrograde approach in 126 of the 281 patients, with antegrade crossing of a guidewire being successful in 88 of them (70%). The retrograde approach was combined with the CART and reverse controlled antegrade retrograde tracking (CART) techniques in 22 and 21 patients, respectively. Among 83 patients treated with Corsair catheters, crossing of the CTO was achieved in 63. The overall procedural success rate was 79.7% (224 patients). Complications of the retrograde approach included collateral channel dissection (2.1%), channel perforation (1.7%), CTO perforation (1.7%), and donor artery occlusion (1.1%). Conclusion The success rate and safety of the retrograde approach are both satisfactory if the appropriate devices and techniques are selected. © 2012 Wiley Periodicals, Inc. PMID:22517670

  1. Physicochemical and release kinetics of natural and retrograded starch of Indian palmyrah shoots.

    PubMed

    Kumar Varma, Ch Ashok; Panpalia, S G; Kumar, K Jayaram

    2014-05-01

    Starch was isolated from the shoots of Indian palmyrah (Borassus flabellifer L.) and it was subjected to the process of retrogradation. The influence of retrogradation on morphological, physicochemical and drug release properties was studied. Retrogradation of native starch changed its morphology from oval, elliptical to crystalline rods. Due to retrogradation there is an increase in amylose content and better hydration capacity, swelling and solubility power. The micromeritic properties of native and retrograded starch uncover its usage as excipients in tablet manufacturing. The retrograded starch showed better powder characteristics to that of native starch. The characteristic peaks for d-glucopyranosyl ring confirms the carbohydrate nature of starch. The TGA data reveals that the retrograded starch shows less bound water to that of native starch during the first decomposition step. In-vitro release study reveals that the retrograded starch attained a better release retardant property and was best explained by Hixson-Crowell model. The result showed that retrograded starches can be used for the preparation of sustained release tablets.

  2. Prevention of retrograde calculus migration with the Stone Cone.

    PubMed

    Pardalidis, N P; Papatsoris, A G; Kosmaoglou, E V

    2005-02-01

    Retrograde calculus migration during ureteroscopic lithotripsy remains a problem in 5-40% of cases. We assessed the safety and efficacy of the Stone Cone device, in comparison with the standard flat wire basket. A total of 56 consecutive patients with ureteral calculi, suitable for ureteroscopic extraction and/or lithotripsy, where included in this prospective study. Patients were randomly allocated into two groups. In group A (30 patients), we used the Stone Cone, while in group B (26 patients) we used the standard flat wire basket. The Stone Cone was placed through a cystoscope under fluoroscopic guidance, or when necessary under direct ureteroscopic control. Whenever necessary, intracorporeal electrohydraulic lithotripsy took place in both groups. Statistical significance was assessed by the paired t-test. The mean operative time was 48.5 min in group A, and 42.4 min in group B. Intact calculus extraction was possible in 16.6% in group A, and in 7.6% in group B (P < 0.01). Retrograde stone migration was revealed in 23% in group B only (P < 0.001). Also, residual fragments > 3 mm were recorded in 30.7% in group B only (P < 0.001). None of the patients in group A required auxiliary procedures, in contrary to 23% in group B (P < 0.001). No major complications were recorded in group A, while in group B a case of major ureteral mucosal abrasion was recorded. The Stone Cone is safe and efficient in preventing retrograde stone migration and in minimizing residual fragments during ureteroscopic lithotripsy in comparison with the flat wire basket.

  3. Hemodynamic changes and retrograde flow in LVAD failure.

    PubMed

    Giridharan, Guruprasad A; Koenig, Steven C; Soucy, Kevin G; Choi, Young; Pirbodaghi, Tohid; Bartoli, Carlo R; Monreal, Gretel; Sobieski, Michael A; Schumer, Erin; Cheng, Allen; Slaughter, Mark S

    2015-01-01

    In the event of left ventricular assist device (LVAD) failure, we hypothesized that rotary blood pumps will experience significant retrograde flow and induce adverse physiologic responses. Catastrophic LVAD failure was investigated in computer simulation with pulsatile, axial, and centrifugal LVAD, mock flow loop with pulsatile (PVAD) and centrifugal (ROTAFLOW), and healthy and chronic ischemic heart failure bovine models with pulsatile (PVAD), axial (HeartMate II), and centrifugal (HVAD) pumps. Simulated conditions were LVAD "off" with outflow graft clamped (baseline), LVAD "off" with outflow graft unclamped (LVAD failure), and LVAD "on" (5 L/min). Hemodynamics (aortic and ventricular blood pressures, LVAD flow, and left ventricular volume), echocardiography (cardiac volumes), and end-organ perfusion (regional blood flow microspheres) were measured and analyzed. Retrograde flow was observed with axial and centrifugal rotary pumps during LVAD failure in computer simulation (axial = -3.4 L/min, centrifugal = -2.8 L/min), mock circulation (pulsatile = -0.1 L/min, centrifugal = -2.7 L/min), healthy (pulsatile = -1.2 ± 0.3 L/min, axial = -2.2 ± 0.2 L/min, centrifugal = -1.9 ± 0.3 L/min), and ischemic heart failure (centrifugal = 2.2 ± 0.7 L/min) bovine models for all test conditions (p < 0.05). Differences between axial and centrifugal LVAD were statistically indiscernible. Retrograde flow increased ventricular end-systolic and end-diastolic volumes and workload, and decreased myocardial and end-organ perfusion during LVAD failure compared with baseline, LVAD support, and pulsatile LVAD failure.

  4. A chloroplast retrograde signal regulates nuclear alternative splicing

    PubMed Central

    Petrillo, Ezequiel; Herz, Micaela A. Godoy; Fuchs, Armin; Reifer, Dominik; Fuller, John; Yanovsky, Marcelo J.; Simpson, Craig; Brown, John W. S.; Barta, Andrea; Kalyna, Maria; Kornblihtt, Alberto R.

    2015-01-01

    Light is a source of energy and also a regulator of plant physiological adaptations. We show here that light/dark conditions affect alternative splicing of a subset of Arabidopsis genes preferentially encoding proteins involved in RNA processing. The effect requires functional chloroplasts and is also observed in roots when the communication with the photosynthetic tissues is not interrupted, suggesting that a signaling molecule travels through the plant. Using photosynthetic electron transfer inhibitors with different mechanisms of action we deduce that the reduced pool of plastoquinones initiates a chloroplast retrograde signaling that regulates nuclear alternative splicing and is necessary for proper plant responses to varying light conditions. PMID:24763593

  5. From Hard to Harder: Iraq Retrograde Lessons for Afghanistan

    DTIC Science & Technology

    2013-04-01

    major commands of Multi-National Force-Iraq ( MNF -I), Multi-National Corps-Iraq (MNC-I), and Multi-National Security Transition Command-Iraq (MNSTC-I...into a single 2 headquarters—US Forces-Iraq (USF-I)—to facilitate the mission change.3 The transition from MNF -I to USF-I was made easier by the...of the MNF -I, MNC-I, and MNSTC-I into USF-I into a single operational chain of command. In support of this retrograde operation, CENTCOM assigned

  6. Utility of retrograde ureterocelogram in management of complex ureterocele.

    PubMed

    Arevalo, M K; Prieto, J C; Cost, N; Nuss, G; Brown, B J; Baker, L A

    2017-02-01

    Symptomatic pediatric ureterocele has diverse manifestations, making evidence-based management impractical. Thus, detailed visualization of ureterocele anatomy prior to first surgical incision is invaluable. Retrograde ureterocelogram (RUC) is a simple, underutilized radiologic technique that can be performed during cystoscopy. This study sought to determine whether RUC changes surgical management by more accurately depicting the complex ureteral and ureterocele anatomy, compared with renal ultrasound (US) and voiding cystourethrography (VCUG). Patients who underwent surgical management of ureterocele from 2003 to 2015 were identified; those who received concomitant fluoroscopic RUC were selected for the case series. Data collected included: demographics, pre-operative evaluation, surgical interventions, and outcomes. The RUC images were individually examined, and the anatomic impression compared with previous renal US and VCUG. Novel RUC findings not previously appreciated by the pre-operative evaluation were noted. The RUC was performed by cystoscopically inserting a needle into the ureterocele and injecting contrast retrograde. If indicated, simultaneous PIC (Positioning the Instillation of Contrast) cystography was performed. Of the 43 patients that underwent surgery for suspected ureterocele, 28 underwent cystoscopy + RUC (10 M: 18 F) at a median age of 4.6 months and median follow-up of 37.0 months. All patients had prior US, 25 had prior VCUG, and 20 had prior radionuclide studies. Ureteroceles were either duplex system (n = 21) or single system (n = 7); 17 were ectopic into the bladder neck or urethra; seven were intravesical; and four were pseudoureteroceles. Fourteen patients underwent concomitant transurethral incision of the ureterocele (TUIU); two were deferred for surgery; and 11 received concomitant definitive surgery (e.g., nephrectomy). The RUC illuminated novel aspects of the anatomy in 20 of the 28 patients. No adverse events occurred

  7. Postcholecystectomy syndrome: evaluation using biliary scintigraphy and endoscopic retrograde cholangiopancreatography

    SciTech Connect

    Zeman, R.K.; Burrell, M.I.; Dobbins, J.; Jaffe, M.K.; Choyke, P.L.

    1985-09-01

    The authors prospectively studied 30 patients with postcholecystectomy syndrome to determine the efficacy of biliary scintigraphy in the detection of stenosis of the sphincter of Oddi. All patients underwent endoscopic retrograde cholangiopancreatography (ERCP). Biliary scintigraphy disclosed stenosis of the sphincter by agreement with the ERCP or surgical findings in nine (90%) of ten patients and in eight (100%) of eight patients with biliary obstruction from other causes. Retention of activity at 2 hours in visually prominent ducts was the best predictor of abnormal biliary drainage. Biliary scintigraphy is a useful, noninvasive screening test for the detection of postcholecystectomy biliary obstruction.

  8. Side Effects of α-Blocker Use: Retrograde Ejaculation

    PubMed Central

    Kaplan, Steven A

    2009-01-01

    There are currently 5 α-blockers that are approved by the US Food and Drug Administration to treat lower urinary tract symptoms (LUTS). The American Urological Association guidelines committee believes that all α-blockers are equally effective. However, α-blockers differ in their likelihood of causing abnormal ejaculation. This article discusses the effects on ejaculatory function, and specifically retrograde ejaculation, of the currently available α-blockers being used to treat men with LUTS due to benign prostatic hyperplasia. PMID:20126607

  9. Filling defects in the pancreatic duct on endoscopic retrograde pancreatography.

    PubMed

    Taylor, A J; Carmody, T J; Schmalz, M J; Wiedmeyer, D A; Stewart, E T

    1992-12-01

    Filling defects in the pancreatic duct are a frequent finding during endoscopic retrograde pancreatography (ERP) and have a variety of causes. Some filling defects may be artifactual or related to technical factors and, once their origin is recognized, can be disregarded. Others may be due to acute changes of pancreatitis and should prompt more careful injection of contrast material into the duct. Intraluminal masses may represent calculi or a neoplasm, either of which may require surgery or endoscopic intervention. The exact nature of these filling defects may not be apparent on radiographs, and other studies may be needed. This article reviews our approach to the evaluation of filling defects in the pancreatic duct.

  10. Retrograde bilin signaling enables Chlamydomonas greening and phototrophic survival.

    PubMed

    Duanmu, Deqiang; Casero, David; Dent, Rachel M; Gallaher, Sean; Yang, Wenqiang; Rockwell, Nathan C; Martin, Shelley S; Pellegrini, Matteo; Niyogi, Krishna K; Merchant, Sabeeha S; Grossman, Arthur R; Lagarias, J Clark

    2013-02-26

    The maintenance of functional chloroplasts in photosynthetic eukaryotes requires real-time coordination of the nuclear and plastid genomes. Tetrapyrroles play a significant role in plastid-to-nucleus retrograde signaling in plants to ensure that nuclear gene expression is attuned to the needs of the chloroplast. Well-known sites of synthesis of chlorophyll for photosynthesis, plant chloroplasts also export heme and heme-derived linear tetrapyrroles (bilins), two critical metabolites respectively required for essential cellular activities and for light sensing by phytochromes. Here we establish that Chlamydomonas reinhardtii, one of many chlorophyte species that lack phytochromes, can synthesize bilins in both plastid and cytosol compartments. Genetic analyses show that both pathways contribute to iron acquisition from extracellular heme, whereas the plastid-localized pathway is essential for light-dependent greening and phototrophic growth. Our discovery of a bilin-dependent nuclear gene network implicates a widespread use of bilins as retrograde signals in oxygenic photosynthetic species. Our studies also suggest that bilins trigger critical metabolic pathways to detoxify molecular oxygen produced by photosynthesis, thereby permitting survival and phototrophic growth during the light period.

  11. Retrograde bilin signaling enables Chlamydomonas greening and phototrophic survival

    PubMed Central

    Duanmu, Deqiang; Casero, David; Dent, Rachel M.; Gallaher, Sean; Yang, Wenqiang; Rockwell, Nathan C.; Martin, Shelley S.; Pellegrini, Matteo; Niyogi, Krishna K.; Merchant, Sabeeha S.; Grossman, Arthur R.; Lagarias, J. Clark

    2013-01-01

    The maintenance of functional chloroplasts in photosynthetic eukaryotes requires real-time coordination of the nuclear and plastid genomes. Tetrapyrroles play a significant role in plastid-to-nucleus retrograde signaling in plants to ensure that nuclear gene expression is attuned to the needs of the chloroplast. Well-known sites of synthesis of chlorophyll for photosynthesis, plant chloroplasts also export heme and heme-derived linear tetrapyrroles (bilins), two critical metabolites respectively required for essential cellular activities and for light sensing by phytochromes. Here we establish that Chlamydomonas reinhardtii, one of many chlorophyte species that lack phytochromes, can synthesize bilins in both plastid and cytosol compartments. Genetic analyses show that both pathways contribute to iron acquisition from extracellular heme, whereas the plastid-localized pathway is essential for light-dependent greening and phototrophic growth. Our discovery of a bilin-dependent nuclear gene network implicates a widespread use of bilins as retrograde signals in oxygenic photosynthetic species. Our studies also suggest that bilins trigger critical metabolic pathways to detoxify molecular oxygen produced by photosynthesis, thereby permitting survival and phototrophic growth during the light period. PMID:23345435

  12. Laser fluorescence angiography reveals perfusion defects in retrograde cardioplegia.

    PubMed

    Gorki, H; Patel, N C; Balacumaraswami, L; Pillai, J B; Subramanian, V A

    2011-11-01

    Adequate perfusion of the right ventricle with retrograde cardioplegia has always been questioned. However, clinical studies suggested sufficient protection and, up to now, intraoperative assessment of cardioplegia distribution has been difficult. As a pilot study in 14 patients, we used indocyanine green laser fluorescence angiography (ICGLA) to assess vascular and myocardial perfusion of different areas of the right anterior ventricular wall. Regions of interest were analyzed quantitatively using a new software package. ICGLA allowed rapid and reliable visualization of cardioplegic flow and distribution. Retrograde cardioplegia revealed perfusion defects in the territory of the right anterior cardiac veins when compared to antegrade delivery and to areas close to the left anterior descending vein(s), confirmed by quantitative analyses of maximal fluorescence intensity. Five patients were excluded from quantitative analyses. The learning curve, pitfalls, limitations and special image details are described. A larger study is necessary to examine the relevance of perfusion defects to metabolic changes in affected myocytes and to global right ventricular function.

  13. Searching for the anatomical basis of retrograde amnesia.

    PubMed

    Markowitsch, H J; Calabrese, P; Haupts, M; Durwen, H F; Liess, J; Gehlen, W

    1993-11-01

    The case of a patient with profound retrograde and minor anterograde amnesia is described and used to discuss the kind of brain damage which will most likely result in persistent retrograde amnesia as the principal symptom. The patient was an industrial manager who had fallen off a horse four years prior to the present neuropsychological and neuroradiological investigation. MRI examination revealed an injury to both temporal poles and to the latero-ventral portion of the right prefrontal cortex. The prefrontal and temporal cortical damage on the right side deeply invaded the white matter while the temporal cortical damage on the left side was much smaller; here, however, portions of the temporo-parietal transition zone were affected as well. The patient was of average intelligence. His attention, short-term memory, and learning ability were average or somewhat below average. His old memories were severely affected in the personal-episodic domain, and much less so in that of semantic remote memory. We conclude from this case that the necessary anatomical substrate for the retrieval of old episodic memories lies within the anterior temporal regions (including deeper situated fiber projections) and possibly involves an interaction with the prefrontal cortex, and that this damage is dissociable from the medial temporal-lobe damage leading to anterograde amnesia.

  14. Role of phospholipase A(2) in retrograde transport of ricin.

    PubMed

    Klokk, Tove Irene; Lingelem, Anne Berit Dyve; Myrann, Anne-Grethe; Sandvig, Kirsten

    2011-09-01

    Ricin is a protein toxin classified as a bioterror agent, for which there are no known treatment options available after intoxication. It is composed of an enzymatically active A-chain connected by a disulfide bond to a cell binding B-chain. After internalization by endocytosis, ricin is transported retrogradely to the Golgi and ER, from where the ricin A-chain is translocated to the cytosol where it inhibits protein synthesis and thus induces cell death. We have identified cytoplasmic phospholipase A(2) (PLA(2)) as an important factor in ricin retrograde transport. Inhibition of PLA(2) protects against ricin challenge, however the toxin can still be endocytosed and transported to the Golgi. Interestingly, ricin transport from the Golgi to the ER is strongly impaired in response to PLA(2) inhibition. Confocal microscopy analysis shows that ricin is still colocalized with the trans-Golgi marker TGN46 in the presence of PLA(2) inhibitor, but less is colocalized with the cis-Golgi marker GM130. We propose that PLA(2) inhibition results in impaired ricin transport through the Golgi stack, thus preventing it from reaching the ER. Consequently, ricin cannot be translocated to the cytosol to exert its toxic action.

  15. Retrograde replacement, reaction-driven cracking and rheology

    NASA Astrophysics Data System (ADS)

    Kelemen, P. B.; Hirth, G.

    2011-12-01

    Retrograde reactions involve hydration, carbonation and/or oxidation of volatile-poor, high grade metamorphic and igneous rocks. They can increase solid volume, via increasing solid mass and decreasing solid density, provided fluid is supplied in an open system, and dissolution does not remove significant solid mass. Increasing solid volume can create deviatoric stress, causing fractures to form. This can be a positive feedback, maintaining or increasing permeability and reactive surface area. Alternatively, high viscosity host rock can act as a rigid container. Transient stress rise due to initial volume change causes nearly equal volumetric rates of precipitation and pressure solution. Retrograde reactions can be self-limiting, consuming fluid that is required both as a reactant and as a catalyst, filling pore space with newly crystallized material, and armoring reactive surface areas. However, retrograde products, such as serpentine, talc and clays are common, and have important controls on crustal rheology and physical properties, e.g., in the "cold nose" above subduction zones, in subducting plates, and in fault zones. The best-known retrograde processes are hydration and carbonation of olivine, in igneous rocks and residual mantle peridotite, e.g. near the seafloor. Fully hydrated (serpentinites) or carbonated (listwanites) peridotites show that retrograde reactions can proceed to completion. It is common to find that replacement is nearly isochemical, with the exception of H2O and CO2, suggesting that large-scale dissolution did not take place and solid volume expansion was significant. The free energy changes driving hydration and carbonation of olivine could generate overpressures of 100's to 1000's of MPa. These thermodynamic upper bounds can be compared to estimates based on microstructure. Evans (Int Geol Rev 2004) and Jamtveit et al. (EPSL 2008) provide microphotographs of igneous troctolites, with interstitial plagioclase surrounding rounded olivine

  16. Anterograde and Retrograde Amnesia of Place Discrimination in Retrosplenial Cortex and Hippocampal Lesioned Rats

    ERIC Educational Resources Information Center

    Haijima, Asahi; Ichitani, Yukio

    2008-01-01

    Retrograde and anterograde amnesic effects of excitotoxic lesions of the rat retrosplenial cortex (RS) and hippocampus (HPC) were investigated. To test retrograde amnesia, rats were trained with two-arm place discrimination in a radial maze 4 wk and 1 d before surgery with a different arm pair, respectively. In the retention test 1 wk after…

  17. Anterograde and Retrograde Amnesia of Place Discrimination in Retrosplenial Cortex and Hippocampal Lesioned Rats

    ERIC Educational Resources Information Center

    Haijima, Asahi; Ichitani, Yukio

    2008-01-01

    Retrograde and anterograde amnesic effects of excitotoxic lesions of the rat retrosplenial cortex (RS) and hippocampus (HPC) were investigated. To test retrograde amnesia, rats were trained with two-arm place discrimination in a radial maze 4 wk and 1 d before surgery with a different arm pair, respectively. In the retention test 1 wk after…

  18. Giant hydronephrosis of a duplex system associated with ureteral ectopia: a cause of retrograde ejaculation.

    PubMed

    Lee, S S; Sun, G H; Yu, D S; Chen, H I; Chang, S Y

    2000-01-01

    Retrograde ejaculation is an extremely rare complication of the ectopic ureter or ectopic ureterocele. In the literature, only two cases have been reported worldwide. In this article the authors describe a patient who has a completely duplicated collecting system with massive dilatation of the upper pole system, which has manifested as a huge abdominal and retroperitoneal mass, complicated by retrograde ejaculation.

  19. Splenic Subcapsular Hematoma After Endoscopic Retrograde Cholangiopancreatography in a Liver Transplant Recipient: Case Report and Literature Review.

    PubMed

    Montenovo, Martin; Javed, Emran; Bakthavatsalam, Ramasamy; Reyes, Jorge

    2017-02-01

    Splenic injuries after an endoscopic retrograde cholangiopancreatography are a rare but lethal complication. We describe a subcapsular splenic hematoma requiring emergent splenectomy after an endoscopic retrograde cholangiopancreatography in a liver transplant recipient.

  20. The effect of branched limit dextrin on corn and waxy corn gelatinization and retrogradation.

    PubMed

    Wang, Lili; Xu, Jin; Fan, Xuerong; Wang, Qiang; Wang, Ping; Yuan, Jiugang; Yu, Yuanyuan; Zhang, Ying; Cui, Li

    2017-08-02

    The effect of branched limit dextrins (BLDs) on the gelatinization and retrogradation properties of corn and waxy corn starch was investigated using differential scanning calorimetry (DSC), wide X-ray diffraction (WXRD). The DSC data showed that the presence of BLDs increased the gelatinization and decreased the gelatinization enthalpy (ΔHgel). The retrogradation of corn and waxy corn starch were retarded by BLDs. The BLD with the lowest molecular weight had the best influence on corn and waxy corn starch retrogradation. The result of WXRD confirmed it. Avrami equation was used to analyze the enthalpies of retrograded corn and waxy corn starch. Starch recrystallization rate (k) reduced with the addition of BLDs, indicating that BLDs reduced the kinetics of starch retrogradation. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Retrograded starches as potential anodes in lithium-ion rechargeable batteries.

    PubMed

    Lian, Xijun; Wen, Yan; Zhu, Wei; Li, Lin; Zhang, Kunsheng; Wang, Wanyu

    2012-11-01

    Retrograded starch is a crystal formed by starch molecules with hydrogen bonds. Many literatures have reported its physicochemical character, but its crystal structure is so far unclear. As we isolate amylose and amylopectin from retrograded maize, sweet potato and potato starches in 4.0 M KOH solutions and make them retrograde alone in neutral solution (adjusted by HCl) to form crystal, a new phenomenon appears, crystals of KCl do not appear in retrograded potato amylose, potato amylopectin, and maize amylose, indicating that those crystals may absorb K⁺ and (or) Cl⁻, and those ions probably act with aldehyde of starch or hydroxy of fatty acid attached in starch, such characteristic may make retrograded starches replace graphite as anode with high-capacity in lithium-ion rechargeable batteries. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Case report: A healthy live birth following icsi with retrograde ejaculated sperm.

    PubMed

    Yakass, Michael B; Woodward, Bryan; Otoo, Mary A; Hiadzi, Edem K

    2014-12-01

    Retrograde ejaculation, sometimes called dry orgasm, refers to the medical condition when semen enters the urinary bladder (retrograde) instead of emerging through the penis after orgasm (antegrade). In some instances, a very minute quantity of antegrade semen appears in the ejaculate and may or may not be devoid of spermatozoa. Complete retrograde ejaculation causes male infertility. Intracytoplasmic sperm injection (ICSI) has been employed to achieve fertilization in some cases of male subfertility, e.g., severe oligoasthenoteratozoospermia. Assisted reproductive techniques to aid conception in cases of retrograde ejaculation have been described extensively elsewhere but there is paucity of knowledge on the occurrence and treatment in Africa. This case report describes the identification and successful treatment of a couple where the male partner suffered from retrograde ejaculation.

  3. A Switch in Retrograde Signaling from Survival to Stress in Rapid Onset Neurodegeneration

    PubMed Central

    Perlson, Eran; Jeong, Goo-Bo; Ross, Jenny L.; Dixit, Ram; Wallace, Karen E.; Kalb, Robert G.; Holzbaur, Erika L.F.

    2011-01-01

    Retrograde axonal transport of cellular signals driven by dynein is vital for neuronal survival. Mouse models with defects in the retrograde transport machinery including the Loa mouse (point mutation in dynein) and the Tgdynamitin mouse (overexpression of dynamitin) exhibit mild neurodegenerative disease. Transport defects have also been observed in more rapidly progressive neurodegeneration, such as that observed in the SOD1G93A transgenic mouse model for familial ALS. Here we test the hypothesis that alterations in retrograde signaling lead to neurodegeneration. In-vivo, in-vitro and live cell imaging motility assays show mis-regulation of transport and inhibition of retrograde signaling in the SOD1G93A model. However, similar inhibition is also seen in the Loa and Tgdynamitin mouse models. Thus, slowing of retrograde signaling leads only to mild degeneration and cannot explain ALS etiology. To further pursue this question, we used a proteomics approach to investigate dynein-associated retrograde signaling. These data indicate a significant decrease in retrograde survival factors including P-Trk and P-Erk1/2, and an increase in retrograde stress factor signaling, including P-JNK, Caspase-8 and p75NTR cleavage fragment in the SOD1G93A model; similar changes are not seen in the Loa mouse. Co-cultures of motor neurons and glia expressing mutant SOD1 (mSOD1) in compartmentalized chambers indicate that inhibition of retrograde stress signaling is sufficient to block activation of cellular stress pathways and to rescue motor neurons from mSOD1-induced toxicity. Hence, a shift from survival-promoting to death-promoting retrograde signaling may be key to the rapid onset of neurodegeneration seen in ALS. PMID:19657041

  4. Myosin IIA dependent retrograde flow drives 3D cell migration.

    PubMed

    Shih, Wenting; Yamada, Soichiro

    2010-04-21

    Epithelial cell migration is an essential part of embryogenesis and tissue regeneration, yet their migration is least understood. Using our three-dimensional (3D) motility analysis, migrating epithelial cells formed an atypical polarized cell shape with the nucleus leading the cell front and a contractile cell rear. Migrating epithelial cells exerted traction forces to deform both the anterior and posterior extracellular matrix toward the cell body. The cell leading edge exhibited a myosin II-dependent retrograde flow with the magnitude and direction consistent with surrounding network deformation. Interestingly, on a two-dimensional substrate, myosin IIA-deficient cells migrated faster than wild-type cells, but in a 3D gel, these myosin IIA-deficient cells were unpolarized and immobile. In contrast, the migration rates of myosin IIB-deficient cells were similar to wild-type cells. Therefore, myosin IIA, not myosin IIB, is required for 3D epithelial cell migration.

  5. Inhibition of wheat starch retrogradation by tea derivatives.

    PubMed

    Zhang, Haihua; Sun, Binghua; Zhang, Shikang; Zhu, Yuejin; Tian, Yaoqi

    2015-12-10

    The effect of four industrial tea derivatives (tea polyphenols [TPS], tea water-soluble extracts [TSE], tea polysaccharides [TSS], and green tea powder [GTP]), on the retrogradation of wheat starch was investigated using texture profile analysis (TPA), differential scanning calorimetry (DSC), rapid viscosity analysis (RVA), and the α-amylase-iodine method. The addition of the four tea derivatives resulted in decreased hardness and increased cohesiveness of the starch gel as shown by the TPA test. The DSC data demonstrated an increase in the enthalpy change of starch gelatinization and a decrease in the enthalpy change of starch recrystallite dissociation. The RVA results indicated that the peak viscosity, representing the intermolecular forces of wheat starch, was reduced after addition of TPS, TSE, and TSS, respectively, but was increased by GTP. Furthermore, the half crystallization time in the Avrami equation almost doubled after the separate addition of the tea derivatives.

  6. Retrograde jejunogastric intussusception with jejunojejunal intussusception (double telescoping)

    PubMed Central

    Sahoo, Manash Ranjan; Bhaskar, Ved; Mohapatra, Vedavyas

    2013-01-01

    A 55-year-old woman presented with features of gastric outlet obstruction not responding to conservative treatment at a peripheral hospital. She had gastric surgery 15 years before. On examination, there was a globular mass palpable in the epigastrium. Ultrasound and endoscopy findings were suggestive of retrograde jejunogastric intussusception. After initial resuscitation, emergency laparotomy was undertaken which revealed a jejunogastric intussusception at the previous retrocolic gastrojejunostomy site. After manual reduction of the intussuscepted loop by gentle traction, another segment of the jejunum was seen to be telescoping within this loop. On reduction, this jejunal loop was seen to measure around 20 cm and the apex of the intussusceptum was found to be gangrenous and perforated. Resection of the involved segment was done followed by a Roux-en-y anastomosis to restore the continuity. PMID:23682086

  7. CONFIRMATION OF A RETROGRADE ORBIT FOR EXOPLANET WASP-17b

    SciTech Connect

    Bayliss, Daniel D. R.; Sackett, Penny D.; Winn, Joshua N.; Mardling, Rosemary A.

    2010-10-20

    We present high-precision radial velocity observations of WASP-17 throughout the transit of its close-in giant planet, using the MIKE spectrograph on the 6.5 m Magellan Telescope at Las Campanas Observatory. By modeling the Rossiter-McLaughlin effect, we find the sky-projected spin-orbit angle to be {lambda} = 167.4 {+-} 11.2 deg. This independently confirms the previous finding that WASP-17b is on a retrograde orbit, suggesting it underwent migration via a mechanism other than just the gravitational interaction between the planet and the disk. Interestingly, our result for {lambda} differs by 45 {+-} 13 deg from the previously announced value, and we also find that the spectroscopic transit occurs 15 {+-} 5 minutes earlier than expected, based on the published ephemeris. The discrepancy in the ephemeris highlights the need for contemporaneous spectroscopic and photometric transit observations whenever possible.

  8. [Hindfoot fusion for Charcot osteoarthropathy with a curved retrograde nail].

    PubMed

    Pyrc, J; Fuchs, A; Zwipp, H; Rammelt, S

    2015-01-01

    Charcot osteoarthropathy of the hindfoot with considerable dislocation and instability represents a therapeutic dilemma. The treatment goal is a plantigrade, stable foot that is free of infection and ulceration with the ability to ambulate in special footwear. Over a period of 6 years, we performed 23 hindfoot fusions in 21 patients with manifest Charcot arthropathy with the help of a curved retrograde nail (HAN). All patients suffered from insulin-dependent diabetes mellitus with polyneuropathy; 12 patients had additional peripheral vasculopathy. An average of 3.5 previous surgeries had been performed prior to hindfoot fusion. Complete tibiotalocalcaneal fusion was obtained in 16 of 21 patients (76 %). Of these 21 patients, 18 (86 %) were followed clinically and radiologically for an average of 2 years. Overall, 16 patients (89 %) reported a substantial subjective improvement compared to the preoperative state. Hardware failure occurred in 7 cases (30 %) that could be brought to consolidation with exchange of the locking bolts or the complete nail. In 5 cases (22 %), a postoperative hematoma had to be removed and in 8 cases (35 %) wound edge necrosis was treated with local wound care. In 2 cases (9 %), a secondary or reactivated osteitis occurred that finally required below knee amputation. Tibiotalocalcaneal fusion with a curved retrograde intramedullary nail (HAN) is an effective treatment option in highly unstable and deforming Charcot osteoarthropathy of the hindfoot. It is an alternative to external or other internal fixation methods and helps to avoid below knee amputation in more than 90 % of cases.

  9. Endoscopic retrograde cholangiopancreatography associated pancreatitis: A 15-year review

    PubMed Central

    Woods, Kevin E; Willingham, Field F

    2010-01-01

    The aim of this article is to review the literature regarding post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis. We searched for and evaluated all articles describing the diagnosis, epidemiology, pathophysiology, morbidity, mortality and prevention of post-ERCP pancreatitis (PEP) in adult patients using the PubMed database. Search terms included endoscopic retrograde cholangiopancreatography, pancreatitis, ampulla of vater, endoscopic sphincterotomy, balloon dilatation, cholangiography, adverse events, standards and utilization. We limited our review of articles to those published between January 1, 1994 and August 15, 2009 regarding human adults and written in the English language. Publications from the reference sections were reviewed and included if they were salient and fell into the time period of interest. Between the dates queried, seventeen large (> 500 patients) prospective and four large retrospective trials were conducted. PEP occurred in 1%-15% in the prospective trials and in 1%-4% in the retrospective trials. PEP was also reduced with pancreatic duct stent placement and outcomes were improved with endoscopic sphincterotomy compared to balloon sphincter dilation in the setting of choledocholithiasis. Approximately 34 pharmacologic agents have been evaluated for the prevention of PEP over the last fifteen years in 63 trials. Although 22 of 63 trials published during our period of review suggested a reduction in PEP, no pharmacologic therapy has been widely accepted in clinical use in decreasing the development of PEP. In conclusion, PEP is a well-recognized complication of ERCP. Medical treatment for prevention has been disappointing. Proper patient selection and pancreatic duct stenting have been shown to reduce the complication rate in randomized clinical trials. PMID:21160744

  10. Antibiotic prophylaxis in retrograde ureteroscopy: what strategy should we adopt?

    PubMed Central

    Pricop, Cătălin; Dorobăt¸, Carmen; Puia, Dragoş; Orsolya, Martha

    2013-01-01

    Background Retrograde ureteroscopy as a minimally invasive treatment of ureteral calculi can be complicated by the occurrence of urinary tract infections. Fever is considered the main indicator of such postoperative complications and we aimed to study its incidence in patients with and without preoperative antibiotic prophylaxis. Methods We included all patients who underwent retrograde ureteroscopy for ureteric stones in the Iaşi and Tg Mureş Urology Clinics from 2009 to 2012. Data were statistically analyzed using the EpiInfo 7 software. Indicative of a statistically significant difference was a p value <0.05. Results We recorded fever in a total of 108 cases, accounting for 22.83% of all subjects in the study. Group 1 included patients who received antibiotic prophylaxis; 48 of 147 (32.65%) were febrile, compared with Group 2 (no antibiotic prophylaxis), where we recorded febrile syndrome in 60 (18.40%) cases, p=0.0009. Comparing the two groups based on calculus size, for stones with diameters of 0.6-0.8 cm 38.71% of patients were febrile in Group 1, compared with 10.88% in Group 2 (p=0.0008). Secondary ureterohydronephrosis did not statistically influence the frequency of fever in any of the studied groups. Conclusion Less than half of all febrile patients had positive urine cultures, which may point to other causes, such as noninfectious factors (aseptic kidney inflammation). This study did not prove the efficiency of preoperative antibiotic prophylaxis; however, based on the clinical experience of the past 120 years, infectious complications are known to be associated with urological maneuvers and prophylaxis could be indicated. PMID:24432295

  11. Conscious Sedation for Endoscopic Retrograde Cholangiopancreatography: Dexmedetomidine Versus Midazolam

    PubMed Central

    Kilic, Neslihan; Sahin, Sukran; Aksu, Hale; Yavascaoglu, Belgin; Gurbet, Alp; Turker, Gurkan; Kadioglu, Asli Guler

    2011-01-01

    Objective: Midazolam and dexmedetomidine, which are used for sedation during endoscopic retrograde cholangiopancreatography, were compared to evaluate the differences in efficacy, hemodynamics, and side effects. Materials and Methods: Fifty patients aged between 18 and 80 were randomly assigned to two groups according to American Society of Anesthesiologists (ASA) classification: Group M received midazolam with an initial bolus infusion of 0.04 mg/kg intravenously (i.v.), followed by additional doses of 0.5 mg i.v. midazolam, titrated to achieve a Ramsay sedation scale score of 3–4. Group D received dexmedetomidine with an initial bolus infusion of 1 mcg/kg/hr i.v. over 10 minutes, followed by a continuous infusion of 0.2–0.7 mcg/kg/hr, titrated to achieve an RSS of 3–4. A Mini Mental Status Examination (MMSE) was performed prior to sedation and in the recovery room once the Modified Aldrete Score (MAS) reached 9–10. Patient heart rates, arterial pressure and pain were evaluated. Results: Patients in Group D had lower heart rates at 20, 25, 30, 35 and 40 minutes following the initiation of sedation (p<0.05). There was no statistical difference in arterial pressure, RSS, MMSE or respiratory rate between the two groups. Coughing, nausea and vomiting occurred in 3 patients in Group M (12%), whereas no patient in Group D experienced these symptoms. The procedure elicited a gag response in 7 patients in Group M (28%) and in 4 patients in Group D (16%), with no significant difference between groups (p>0.05). When patient and surgeon satisfaction was compared between the two groups, Group D showed higher surgeon satisfaction scores (p<0.05). Conclusion: The use of dexmedetomidine for conscious sedation during short, invasive procedures, such as endoscopic retrograde cholangiopancreatography, could be a superior alternative to the use of midazolam. PMID:25610153

  12. Is retrograde drilling really useful for osteochondral lesion of talus with subchondral cyst?

    PubMed Central

    Jeong, Seong-Yup; Kim, Jong-Kil; Lee, Kwang-Bok

    2016-01-01

    Abstract Rationale: Retrograde drilling is a well accepted procedure for osteochondral lesion of the talus and subchondral cyst with intact overlying cartilage. It has good results in most reports. Compared to anterograde drilling, retrograde drilling can protect the integrity of the articular cartilage. The purpose of this study was to evaluate the suitability of using retrograde drilling for osteochondral lesion with subchondral cyst and discuss the mechanism involved in the development of subchondral cyst. Patient concerns: We report a 53-year-old man who had complained left ankle pain that lasted over 6 months which was exacerbated by walking. Diagnoses: We diagnosed it as osteochondral lesion of the talus with subchondral cyst. Interventions: Plain X-ray, computed tomography, and magnetic resonance imaging (MRI) of the ankle. Outcomes: He undertook retrograde drilling without debridement of cartilage. After the surgery, the pain had been subsided for 1 year, although arthritic change had progressed. However, after 5 years of retrograde drilling, he revisited our hospital due to severe ankle pain. Plain X-ray and MRI showed arthritic change of the ankle and multiple cystic formation of talus. Lessons: Retrograde drilling has some problem because this procedure is not theoretically correct when the development of a subchondral cyst in osteochondral lesion of the talus is considered. In addition, retrograde drilling may impair uninjured bone marrow of the talus, resulting in the development of multiple cystic formations. PMID:27930520

  13. Effects of protein in wheat flour on retrogradation of wheat starch.

    PubMed

    Xijun, Lian; Junjie, Guo; Danli, Wang; Lin, Li; Jiaran, Zhu

    2014-08-01

    Albumins, globulins, gliadins, and glutenins were isolated from wheat flour and the effects of those proteins on retrogradation of wheat starch were investigated. The results showed that only glutenins retarded retrogradation of wheat starch and other 3 proteins promoted it. The results of IR spectra proved that no S-S linkage formed during retrogradation of wheat starch blended with wheat proteins. Combination of wheat starch and globulins or gliadins through glucosidic bonds hindered the hydrolysis of wheat starch by α-amylase. The melting peak temperatures of retrograded wheat starch attached to different proteins were 128.46, 126.14, 132.03, 121.65, and 134.84 °C for the control with no protein, albumins, glutenins, globulins, gliadins groups, respectively, and there was no second melting temperature for albumins group. Interaction of wheat proteins and starch in retrograded wheat starch greatly decreased the endothermic enthalpy (△H) of retrograded wheat starch. Retrograded wheat starch bound to gliadins might be a new kind of resistant starch based on glycosidic bond between starch and protein.

  14. The retromer complex and clathrin define an early endosomal retrograde exit site.

    PubMed

    Popoff, Vincent; Mardones, Gonzalo A; Tenza, Danièle; Rojas, Raúl; Lamaze, Christophe; Bonifacino, Juan S; Raposo, Graça; Johannes, Ludger

    2007-06-15

    Previous studies have indicated a role for clathrin, the clathrin adaptors AP1 and epsinR, and the retromer complex in retrograde sorting from early/recycling endosomes to the trans Golgi network (TGN). However, it has remained unclear whether these protein machineries function on the same or parallel pathways. We show here that clathrin and the retromer subunit Vps26 colocalize at the ultrastructural level on early/recycling endosomes containing Shiga toxin B-subunit, a well-studied retrograde transport cargo. As previously described for clathrin, we find that interfering with Vps26 expression inhibits retrograde transport of the Shiga toxin B-subunit to the TGN. Under these conditions, endosomal tubules that take the Shiga toxin B-subunit out of transferrin-containing early/recycling endosomes appear to be stabilized. This situation differs from that previously described for low-temperature incubation and clathrin-depletion conditions under which Shiga toxin B-subunit labeling was found to overlap with that of the transferrin receptor. In addition, we find that the Shiga toxin B-subunit and the transferrin receptor accumulate close to multivesicular endosomes in clathrin-depleted cells, suggesting that clathrin initiates retrograde sorting on vacuolar early endosomes, and that retromer is then required to process retrograde tubules. Our findings thus establish a role for the retromer complex in retrograde transport of the B-subunit of Shiga toxin, and strongly suggest that clathrin and retromer function in consecutive retrograde sorting steps on early endosomes.

  15. Is retrograde drilling really useful for osteochondral lesion of talus with subchondral cyst?: A case report.

    PubMed

    Jeong, Seong-Yup; Kim, Jong-Kil; Lee, Kwang-Bok

    2016-12-01

    Retrograde drilling is a well accepted procedure for osteochondral lesion of the talus and subchondral cyst with intact overlying cartilage. It has good results in most reports. Compared to anterograde drilling, retrograde drilling can protect the integrity of the articular cartilage. The purpose of this study was to evaluate the suitability of using retrograde drilling for osteochondral lesion with subchondral cyst and discuss the mechanism involved in the development of subchondral cyst. We report a 53-year-old man who had complained left ankle pain that lasted over 6 months which was exacerbated by walking. We diagnosed it as osteochondral lesion of the talus with subchondral cyst. Plain X-ray, computed tomography, and magnetic resonance imaging (MRI) of the ankle. He undertook retrograde drilling without debridement of cartilage. After the surgery, the pain had been subsided for 1 year, although arthritic change had progressed. However, after 5 years of retrograde drilling, he revisited our hospital due to severe ankle pain. Plain X-ray and MRI showed arthritic change of the ankle and multiple cystic formation of talus. Retrograde drilling has some problem because this procedure is not theoretically correct when the development of a subchondral cyst in osteochondral lesion of the talus is considered. In addition, retrograde drilling may impair uninjured bone marrow of the talus, resulting in the development of multiple cystic formations.

  16. The Yeast Retrograde Response as a Model of Intracellular Signaling of Mitochondrial Dysfunction

    PubMed Central

    Jazwinski, S. Michal; Kriete, Andres

    2012-01-01

    Mitochondrial dysfunction activates intracellular signaling pathways that impact yeast longevity, and the best known of these pathways is the retrograde response. More recently, similar responses have been discerned in other systems, from invertebrates to human cells. However, the identity of the signal transducers is either unknown or apparently diverse, contrasting with the well-established signaling module of the yeast retrograde response. On the other hand, it has become equally clear that several other pathways and processes interact with the retrograde response, embedding it in a network responsive to a variety of cellular states. An examination of this network supports the notion that the master regulator NFκB aggregated a variety of mitochondria-related cellular responses at some point in evolution and has become the retrograde transcription factor. This has significant consequences for how we view some of the deficits associated with aging, such as inflammation. The support for NFκB as the retrograde response transcription factor is not only based on functional analyses. It is bolstered by the fact that NFκB can regulate Myc–Max, which is activated in human cells with dysfunctional mitochondria and impacts cellular metabolism. Myc–Max is homologous to the yeast retrograde response transcription factor Rtg1–Rtg3. Further research will be needed to disentangle the pro-aging from the anti-aging effects of NFκB. Interestingly, this is also a challenge for the complete understanding of the yeast retrograde response. PMID:22629248

  17. Diagnosis of Acute Appendicitis by Endoscopic Retrograde Appendicitis Therapy (ERAT): Combination of Colonoscopy and Endoscopic Retrograde Appendicography.

    PubMed

    Li, Yingchao; Mi, Chen; Li, Weizhi; She, Junjun

    2016-11-01

    Acute appendicitis is the most common abdominal emergency, but the diagnosis of appendicitis remains a challenge. Endoscopic retrograde appendicitis therapy (ERAT) is a new and minimally invasive procedure for the diagnosis and treatment of acute appendicitis. To investigate the diagnostic value of ERAT for acute appendicitis by the combination of colonoscopy and endoscopic retrograde appendicography (ERA). Twenty-one patients with the diagnosis of suspected uncomplicated acute appendicitis who underwent ERAT between November 2014 and January 2015 were included in this study. The main outcomes, imaging findings of acute appendicitis including colonoscopic direct-vision imaging and fluoroscopic ERA imaging, were retrospectively reviewed. Secondary outcomes included mean operative time, mean hospital stay, rate of complication, rate of appendectomy during follow-up period, and other clinical data. The diagnosis of acute appendicitis was established in 20 patients by positive ERA (5 patients) or colonoscopy (1 patient) alone or both (14 patients). The main colonoscopic imaging findings included mucosal inflammation (15/20, 75 %), appendicoliths (14/20, 70 %), and maturation (5/20, 25 %). The key points of ERA for diagnosing acute appendicitis included radiographic changes of appendix (17/20, 85 %), intraluminal appendicoliths (14/20, 70 %), and perforation (1/20, 5 %). Mean operative time of ERAT was 49.7 min, and mean hospital stay was 3.3 days. No patient converted to emergency appendectomy. Perforation occurred in one patient after appendicoliths removal was not severe and did not require invasive procedures. During at least 1-year follow-up period, only one patient underwent laparoscopic appendectomy. ERAT is a valuable procedure of choice providing a precise yield of diagnostic information for patients with suspected acute appendicitis by combination of colonoscopy and ERA.

  18. RAB-6.1 and RAB-6.2 Promote Retrograde Transport in C. elegans

    PubMed Central

    Zhang, Donglei; Dubey, Jyoti; Koushika, Sandhya P.; Rongo, Christopher

    2016-01-01

    Retrograde transport is a critical mechanism for recycling certain membrane cargo. Following endocytosis from the plasma membrane, retrograde cargo is moved from early endosomes to Golgi followed by transport (recycling) back to the plasma membrane. The complete molecular and cellular mechanisms of retrograde transport remain unclear. The small GTPase RAB-6.2 mediates the retrograde recycling of the AMPA-type glutamate receptor (AMPAR) subunit GLR-1 in C. elegans neurons. Here we show that RAB-6.2 and a close paralog, RAB-6.1, together regulate retrograde transport in both neurons and non-neuronal tissue. Mutants for rab-6.1 or rab-6.2 fail to recycle GLR-1 receptors, resulting in GLR-1 turnover and behavioral defects indicative of diminished GLR-1 function. Loss of both rab-6.1 and rab-6.2 results in an additive effect on GLR-1 retrograde recycling, indicating that these two C. elegans Rab6 isoforms have overlapping functions. MIG-14 (Wntless) protein, which undergoes retrograde recycling, undergoes a similar degradation in intestinal epithelia in both rab-6.1 and rab-6.2 mutants, suggesting a broader role for these proteins in retrograde transport. Surprisingly, MIG-14 is localized to separate, spatially segregated endosomal compartments in rab-6.1 mutants compared to rab-6.2 mutants. Our results indicate that RAB-6.1 and RAB-6.2 have partially redundant functions in overall retrograde transport, but also have their own unique cellular- and subcellular functions. PMID:26891225

  19. RAB-6.1 and RAB-6.2 Promote Retrograde Transport in C. elegans.

    PubMed

    Zhang, Donglei; Dubey, Jyoti; Koushika, Sandhya P; Rongo, Christopher

    2016-01-01

    Retrograde transport is a critical mechanism for recycling certain membrane cargo. Following endocytosis from the plasma membrane, retrograde cargo is moved from early endosomes to Golgi followed by transport (recycling) back to the plasma membrane. The complete molecular and cellular mechanisms of retrograde transport remain unclear. The small GTPase RAB-6.2 mediates the retrograde recycling of the AMPA-type glutamate receptor (AMPAR) subunit GLR-1 in C. elegans neurons. Here we show that RAB-6.2 and a close paralog, RAB-6.1, together regulate retrograde transport in both neurons and non-neuronal tissue. Mutants for rab-6.1 or rab-6.2 fail to recycle GLR-1 receptors, resulting in GLR-1 turnover and behavioral defects indicative of diminished GLR-1 function. Loss of both rab-6.1 and rab-6.2 results in an additive effect on GLR-1 retrograde recycling, indicating that these two C. elegans Rab6 isoforms have overlapping functions. MIG-14 (Wntless) protein, which undergoes retrograde recycling, undergoes a similar degradation in intestinal epithelia in both rab-6.1 and rab-6.2 mutants, suggesting a broader role for these proteins in retrograde transport. Surprisingly, MIG-14 is localized to separate, spatially segregated endosomal compartments in rab-6.1 mutants compared to rab-6.2 mutants. Our results indicate that RAB-6.1 and RAB-6.2 have partially redundant functions in overall retrograde transport, but also have their own unique cellular- and subcellular functions.

  20. Coronary perforation with tamponade successfully managed by retrograde and antegrade coil embolization.

    PubMed

    Boukhris, Marouane; Tomasello, Salvatore Davide; Azzarelli, Salvatore; Elhadj, Zied Ibn; Marzà, Francesco; Galassi, Alfredo Ruggero

    2015-07-01

    In recent years, retrograde approach for chronic total occlusions has rapidly evolved, enabling a higher rate of revascularization success. Compared to septal channels, epicardial collaterals tend to be more tortuous, more difficult to negotiate, and more prone to rupture. Coronary perforation is a rare but potentially life-threatening complication of coronary angioplasty, often leading to emergency cardiac surgery. We report a case of a retrograde chronic total occlusion revascularization through epicardial collaterals, complicated by both retrograde and antegrade coronary perforation with tamponade, and successfully managed by coil embolization.

  1. TCTEX1D2 mutations underlie Jeune asphyxiating thoracic dystrophy with impaired retrograde intraflagellar transport

    PubMed Central

    Schmidts, Miriam; Hou, Yuqing; Cortés, Claudio R.; Mans, Dorus A.; Huber, Celine; Boldt, Karsten; Patel, Mitali; van Reeuwijk, Jeroen; Plaza, Jean-Marc; van Beersum, Sylvia E. C.; Yap, Zhi Min; Letteboer, Stef J. F.; Taylor, S. Paige; Herridge, Warren; Johnson, Colin A.; Scambler, Peter J.; Ueffing, Marius; Kayserili, Hulya; Krakow, Deborah; King, Stephen M.; Beales, Philip L.; Al-Gazali, Lihadh; Wicking, Carol; Cormier-Daire, Valerie; Roepman, Ronald; Mitchison, Hannah M.; Witman, George B.; Al-Turki, Saeed; Anderson, Carl; Anney, Richard; Antony, Dinu; Asimit, Jennifer; Ayub, Mohammad; Barrett, Jeff; Barroso, Inês; Bentham, Jamie; Bhattacharya, Shoumo; Blackwood, Douglas; Bobrow, Martin; Bochukova, Elena; Bolton, Patrick; Boustred, Chris; Breen, Gerome; Brion, Marie-Jo; Brown, Andrew; Calissano, Mattia; Carss, Keren; Chatterjee, Krishna; Chen, Lu; Cirak, Sebhattin; Clapham, Peter; Clement, Gail; Coates, Guy; Collier, David; Cosgrove, Catherine; Cox, Tony; Craddock, Nick; Crooks, Lucy; Curran, Sarah; Daly, Allan; Danecek, Petr; Smith, George Davey; Day-Williams, Aaron; Day, Ian; Durbin, Richard; Edkins, Sarah; Ellis, Peter; Evans, David; Farooqi, I. Sadaf; Fatemifar, Ghazaleh; Fitzpatrick, David; Flicek, Paul; Floyd, Jamie; Foley, A. Reghan; Franklin, Chris; Futema, Marta; Gallagher, Louise; Gaunt, Tom; Geschwind, Daniel; Greenwood, Celia; Grozeva, Detelina; Guo, Xiaosen; Gurling, Hugh; Hart, Deborah; Hendricks, Audrey; Holmans, Peter; Huang, Jie; Humphries, Steve E.; Hurles, Matt; Hysi, Pirro; Jackson, David; Jamshidi, Yalda; Jewell, David; Chris, Joyce; Kaye, Jane; Keane, Thomas; Kemp, John; Kennedy, Karen; Kent, Alastair; Kolb-Kokocinski, Anja; Lachance, Genevieve; Langford, Cordelia; Lee, Irene; Li, Rui; Li, Yingrui; Ryan, Liu; Lönnqvist, Jouko; Lopes, Margarida; MacArthur, Daniel G.; Massimo, Mangino; Marchini, Jonathan; Maslen, John; McCarthy, Shane; McGuffin, Peter; McIntosh, Andrew; McKechanie, Andrew; McQuillin, Andrew; Memari, Yasin; Metrustry, Sarah; Min, Josine; Moayyeri, Alireza; Morris, James; Muddyman, Dawn; Muntoni, Francesco; Northstone, Kate; O'Donovan, Michael; O'Rahilly, Stephen; Onoufriadis, Alexandros; Oualkacha, Karim; Owen, Michael; Palotie, Aarno; Panoutsopoulou, Kalliope; Parker, Victoria; Parr, Jeremy; Paternoster, Lavinia; Paunio, Tiina; Payne, Felicity; Perry, John; Pietilainen, Olli; Plagnol, Vincent; Quail, Michael A.; Quaye, Lydia; Raymond, Lucy; Rehnström, Karola; Brent Richards, J.; Ring, Sue; Ritchie, Graham R S; Savage, David B.; Schoenmakers, Nadia; Semple, Robert K.; Serra, Eva; Shihab, Hashem; Shin, So-Youn; Skuse, David; Small, Kerrin; Smee, Carol; Soler, Artigas María; Soranzo, Nicole; Southam, Lorraine; Spector, Tim; St Pourcain, Beate; St. Clair, David; Stalker, Jim; Surdulescu, Gabriela; Suvisaari, Jaana; Tachmazidou, Ioanna; Tian, Jing; Timpson, Nic; Tobin, Martin; Valdes, Ana; van Kogelenberg, Margriet; Vijayarangakannan, Parthiban; Wain, Louise; Walter, Klaudia; Wang, Jun; Ward, Kirsten; Wheeler, Ellie; Whittall, Ros; Williams, Hywel; Williamson, Kathy; Wilson, Scott G.; Wong, Kim; Whyte, Tamieka; ChangJiang, Xu; Zeggini, Eleftheria; Zhang, Feng; Zheng, Hou-Feng

    2015-01-01

    The analysis of individuals with ciliary chondrodysplasias can shed light on sensitive mechanisms controlling ciliogenesis and cell signalling that are essential to embryonic development and survival. Here we identify TCTEX1D2 mutations causing Jeune asphyxiating thoracic dystrophy with partially penetrant inheritance. Loss of TCTEX1D2 impairs retrograde intraflagellar transport (IFT) in humans and the protist Chlamydomonas, accompanied by destabilization of the retrograde IFT dynein motor. We thus define TCTEX1D2 as an integral component of the evolutionarily conserved retrograde IFT machinery. In complex with several IFT dynein light chains, it is required for correct vertebrate skeletal formation but may be functionally redundant under certain conditions. PMID:26044572

  2. Independent predictors of retrograde failure in CTO-PCI after successful collateral channel crossing.

    PubMed

    Suzuki, Yoriyasu; Muto, Makoto; Yamane, Masahisa; Muramatsu, Toshiya; Okamura, Atsunori; Igarashi, Yasumi; Fujita, Tsutomu; Nakamura, Shigeru; Oida, Akitsugu; Tsuchikane, Etsuo

    2017-07-01

    To evaluate factors for predicting retrograde CTO-PCI failure after successful collateral channel crossing. Successful guidewire/catheter collateral channel crossing is important for the retrograde approach in percutaneous coronary intervention (PCI) for chronic total occlusion (CTO). A total of 5984 CTO-PCI procedures performed in 45 centers in Japan from 2009 to 2012 were studied. The retrograde approach was used in 1656 CTO-PCIs (27.7%). We investigated these retrograde procedures to evaluate factors for predicting retrograde CTO-PCI failure even after successful collateral channel crossing. Successful guidewire/catheter collateral crossing was achieved in 77.1% (n = 1,276) of 1656 retrograde CTO-PCI procedures. Retrograde procedural success after successful collateral crossing was achieved in 89.4% (n = 1,141). Univariate analysis showed that the predictors for retrograde CTO-PCI failure were in-stent occlusion (OR = 1.9829, 95%CI = 1.1783 - 3.3370 P = 0.0088), calcified lesions (OR = 1.9233, 95%CI = 1.2463 - 2.9679, P = 0.0027), and lesion tortuosity (OR = 1.5244, 95%CI = 1.0618 - 2.1883, P = 0.0216). On multivariate analysis, lesion calcification was an independent predictor of retrograde CTO-PCI failure after successful collateral channel crossing (OR = 1.3472, 95%CI = 1.0614 - 1.7169, P = 0.0141). The success rate of retrograde CTO-PCI following successful guidewire/catheter collateral channel crossing was high in this registry. Lesion calcification was an independent predictor of retrograde CTO-PCI failure after successful collateral channel crossing. Devices and techniques to overcome complex CTO lesion morphology, such as lesion calcification, are required to further improve the retrograde CTO-PCI success rate. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Materials for retrograde filling in root canal therapy.

    PubMed

    Ma, Xiangyu; Li, Chunjie; Jia, Liuhe; Wang, Yan; Liu, Wenwen; Zhou, Xuedong; Johnson, Trevor M; Huang, Dingming

    2016-12-17

    Root canal therapy is a sequence of treatments involving root canal cleaning, shaping, decontamination and obturation. It is conventionally performed through a hole drilled into the crown of the affected tooth, namely orthograde root canal therapy. For teeth that cannot be treated with orthograde root canal therapy, or for which it has failed, retrograde root filling, which seals the root canal from the root apex, is a good alternative. Many materials, such as amalgam, zinc oxide eugenol and mineral trioxide aggregate (MTA), are generally used. Since none meets all the criteria an ideal material should possess, selecting the most efficacious material is of utmost importance. To determine the effects of different materials used for retrograde filling in children and adults for whom retrograde filling is necessary in order to save the tooth. Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 13 September 2016); the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 8) in the Cochrane Library (searched 13 September 2016); MEDLINE Ovid (1946 to 13 September 2016); Embase Ovid (1980 to 13 September 2016); LILACS BIREME Virtual Health Library (1982 to 13 September 2016); and OpenSIGLE (1980 to 2005). ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. We also searched Chinese BioMedical Literature Database (in Chinese, 1978 to 20 September 2016); VIP (in Chinese, 1989 to 20 September 2016); China National Knowledge Infrastructure (in Chinese, 1994 to 20 September 2016); and Sciencepaper Online (in Chinese, to 20 September 2016). No restrictions were placed on the language or date of publication when searching the electronic databases. We selected randomised controlled trials (RCTs) only that compared different retrograde filling materials, with reported success rate that was assessed by clinical or

  4. Antibody-mediated inhibition of ricin toxin retrograde transport.

    PubMed

    Yermakova, Anastasiya; Klokk, Tove Irene; Cole, Richard; Sandvig, Kirsten; Mantis, Nicholas J

    2014-04-08

    Ricin is a member of the ubiquitous family of plant and bacterial AB toxins that gain entry into the cytosol of host cells through receptor-mediated endocytosis and retrograde traffic through the trans-Golgi network (TGN) and endoplasmic reticulum (ER). While a few ricin toxin-specific neutralizing monoclonal antibodies (MAbs) have been identified, the mechanisms by which these antibodies prevent toxin-induced cell death are largely unknown. Using immunofluorescence confocal microscopy and a TGN-specific sulfation assay, we demonstrate that 24B11, a MAb against ricin's binding subunit (RTB), associates with ricin in solution or when prebound to cell surfaces and then markedly enhances toxin uptake into host cells. Following endocytosis, however, toxin-antibody complexes failed to reach the TGN; instead, they were shunted to Rab7-positive late endosomes and LAMP-1-positive lysosomes. Monovalent 24B11 Fab fragments also interfered with toxin retrograde transport, indicating that neither cross-linking of membrane glycoproteins/glycolipids nor the recently identified intracellular Fc receptor is required to derail ricin en route to the TGN. Identification of the mechanism(s) by which antibodies like 24B11 neutralize ricin will advance our fundamental understanding of protein trafficking in mammalian cells and may lead to the discovery of new classes of toxin inhibitors and therapeutics for biodefense and emerging infectious diseases. IMPORTANCE Ricin is the prototypic member of the AB family of medically important plant and bacterial toxins that includes cholera and Shiga toxins. Ricin is also a category B biothreat agent. Despite ongoing efforts to develop vaccines and antibody-based therapeutics against ricin, very little is known about the mechanisms by which antibodies neutralize this toxin. In general, it is thought that antibodies simply prevent toxins from attaching to cell surface receptors or promote their clearance through Fc receptor (FcR)-mediated uptake

  5. A Narrow QRS Complex Tachycardia With An Apparently Concentric Retrograde Atrial Activation Sequence

    PubMed Central

    Arias, Miguel A; Castellanos, Eduardo; Puchol, Alberto; Pachon, Marta

    2009-01-01

    The retrograde atrial activation sequence constitutes an initial important clue to elucidate the tachycardia mechanism during diagnostic electrophysiological testing in patients with supraventricular tachycardia. However, in some cases its correct analysis is challenging. PMID:19308284

  6. A photographic approach to the possible mechanism of retrogradation of sweet potato starch.

    PubMed

    Lian, Xijun; Zhao, Shuyi; Liu, Qinsheng; Zhang, Xu

    2011-01-01

    Although the subject of starch retrogradation has been studied for about 20 years, the mechanism of starch retrogradation seems not yet to be completely established. In this paper, the possible retrogradation mechanism of sweet potato starch was postulated from four optical micrographs at the stages of melting of the starch granules, autoclaving treatment and aging. The possible process of retrogradation consists of three stages. Firstly, starch granules was swelled and melted with loss of X-ray crystallinity and formation of both crystalline and amorphous lamellae; secondly, in crystalline lamellae, amylopectin began to form nucleation when they were autoclaved; finally, the nucleus grew up to great rod-like crystals as the result of congregating of amylose on plates which were composed of and prolongated by amylopectin.

  7. Fiberoptic Guided Retrograde Intubation in an Anticipated Difficult Airway: Revival of an Antiquated Technique

    PubMed Central

    Ninu, Marie; Yunus, Md.; Syiemiong, Newstar

    2016-01-01

    Retrograde intubation is an invaluable technique which can be helpful in anticipated difficult airway situation. In this advanced era where fiberoptic intubation and video laryngoscopes are in abundant use, retrograde intubation is a forgotten technique. However, it may be useful in various difficult airway situations in this advanced era. In our case the patient had a bitter experience with previous fiberoptic intubation. Owing to that we had planned and performed a fiber optic guided retrograde intubation, where we had kept the fiberoptic bronchoscope in the pharynx keeping larynx and vocal cords in the focus to facilitate the emergence of guide wire through one of the nostrils as well as direct visual confirmation of intubation. This fiber optic guided retrograde intubation is a first reported case of its kind in a predicted difficult airway which can be beneficial in different difficult airway situations. PMID:27891428

  8. Retrograde left ventricular catheterization in patients with an aortic valve prosthesis.

    PubMed

    Karsh, D L; Michaelson, S P; Langou, R A; Cohen, L S; Wolfson, S

    1978-05-01

    Twenty-seven consecutive patients with an aortic valve prosthesis were evaluated with retrograde left ventricular catheterization. The prosthesis was successfully crossed, permitting hemodynamic and angiographic evaluation of function of the prosthetic valve, left ventricle and mitral valve in all 27 cases. No complications were encountered. In patients with active endocarditis or recent embolization, the retrograde technique was avoided when possible, and attempts were made to utilize other techniques for study. However, three such patients were evaluated with the retrograde technique without complication. Examination of pressure tracings and cineangiographic films suggested only minor interference with valve poppet movement induced by the catheter transversing the valve. In three cases, hemodynamic data were recorded with the catheter crossing the prosthesis at one time and a paraprosthetic valve defect at another time. Identical gradients were recorded. This series documents the safety and efficacy of the retrograde approach, which is proposed as an alternative to the transseptal technique and left ventricular puncture.

  9. Reducing retrogradation and lipid oxidation of normal and glutinous rice flours by adding mango peel powder.

    PubMed

    Siriamornpun, Sirithon; Tangkhawanit, Ekkarat; Kaewseejan, Niwat

    2016-06-15

    Green and ripe mango peel powders (MPP) were added to normal rice flour (NRF) and glutinous rice flour (GRF) at three levels (400, 800 and 1200 ppm) and their effects on physicochemical properties and lipid oxidation inhibition were investigated. Overall, MPP increased the breakdown viscosity and reduced the final viscosity in rice flours when compared to the control. Decreasing in retrogradation was observed in both NRF and GRF with MPP added of all levels. MPP addition also significantly inhibited the lipid oxidation of all flours during storage (30 days). Retrogradation values were strongly negatively correlated with total phenolic and flavonoid contents, but not with fiber content. The hydrogen bonds and hydrophilic interactions between phenolic compounds with amylopectin molecule may be involved the decrease of starch retrogradation, especially GRF. We suggest that the addition of MPP not only reduced the retrogradation but also inhibited the lipid oxidation of rice flour.

  10. Yeast as a tool to study mitochondrial retrograde pathway en route to cell stress response.

    PubMed

    Ždralević, Maša; Guaragnella, Nicoletta; Giannattasio, Sergio

    2015-01-01

    Mitochondrial retrograde signaling is a mitochondria-to-nucleus communication pathway, conserved from yeast to humans, by which dysfunctional mitochondria relay signals that lead to cell stress adaptation in physiopathological conditions by changes in nuclear gene expression. The best comprehension of components and regulation of retrograde signaling have been obtained in Saccharomyces cerevisiae, where retrograde target gene expression is regulated by RTG genes. In this chapter, we describe the methods to measure mitochondrial retrograde pathway activation in yeast cells by monitoring the mRNA levels of RTG target genes, such as those encoding for peroxisomal citrate synthase, aconitase, and NAD(+)-specific isocitrate dehydrogenase subunit 1, as well as the phosphorylation status of Rtg1/3p transcriptional factor which controls RTG target gene transcription.

  11. Analysis of human ejaculation using color Doppler ultrasonography: a comparison between antegrade and retrograde ejaculation.

    PubMed

    Nagai, Atsushi; Watanabe, Masami; Nasu, Yasutomo; Iguchi, Hiroki; Kusumi, Norihiro; Kumon, Hiromi

    2005-02-01

    To observe the phenomenon of human ejaculation dynamically using color Doppler ultrasonography. Human ejaculation was observed using transrectal color Doppler ultrasonography in a healthy man and a patient with retrograde ejaculation. Ejaculation was induced manually with audiovisual sexual stimulation. The ejaculatory phenomenon was analyzed and compared with that of retrograde ejaculation. In the healthy man, the prostatic urethra flattened slightly and the bladder neck contracted just before expulsion. The ejaculatory stream spurted from the seminal vesicles to the bulbous urethra through the ejaculatory duct. In the patient with retrograde ejaculation, the ejaculatory stream from the seminal vesicles and inframontanal and distal prostatic urethras distended into a globular-shaped sac filled with semen. No seminal flow toward the bulbous urethra occurred. The semen remaining in the prostatic urethra began flowing slowly into the bladder. Differences between antegrade and retrograde ejaculation can be clearly detected by color Doppler ultrasonography, providing a noninvasive method to diagnose ejaculatory disorders.

  12. Fundamental studies of retrograde reactions in direct liquefaction. Topical report, September 30, 1988--September 30, 1989

    SciTech Connect

    Serio, M.A.; Solomon, P.R.; Bassilakis, R.; Kroo, E.

    1989-12-31

    Most of the proposed processing schemes for improving liquefaction yields involve favoring bond-breaking and radical stabilization reactions over the retrograde reactions. The retrograde reactions are often encountered before liquefaction temperatures are reached. The objective of this program is to elucidate and model the retrograde reaction chemistry in direct coal liquefaction through the application of experimental techniques and theoretical models which have been successfully employed at Advanced Fuel Research (AFR) and SRI International (a subcontractor) to understand and predict coal reaction behavior. The study of retrograde reactions is being done using an integrated approach using extensive characterization of the liquefaction chemistry of three kinds of systems: (1) model polymers; (2) coal; and (3) modified coals.

  13. Pancreatitis with an unusual fatal complication following endoscopic retrograde cholangiopancreaticography: a case report

    PubMed Central

    Kanen, Boris; Loffeld, Ruud JLF

    2008-01-01

    Introduction Endoscopic retrograde cholangiopancreaticography has been the treatment of choice for stones in the common bile duct. Although the procedure is usually safe, procedure-related complications do occur. Case presentation A case of pancreatitis following endoscopic retrograde cholangiopancreaticography is described in a 55-year-old woman. After an uneventful recovery the patient's condition deteriorated rapidly 16 days after the endoscopic retrograde cholangiopancreaticography, and the patient died within 1 hour. Post-mortem examination revealed massive intrapulmonary fat embolism. The complications of endoscopic retrograde cholangiopancreaticography and pancreatitis are described. Conclusion Fat embolism can occur after the remission of pancreatitis and pancreatic necrosis may be overlooked on contrast-enhanced computed tomography scanning. PMID:18577211

  14. Veiled right kidney sign in retroperitoneal duodenal perforation after endoscopic retrograde cholangiopancreatography.

    PubMed

    Banerji, John Samuel

    2011-08-01

    Retropneumoperitoneum due to duodenal perforation after endoscopic retrograde cholangiopancreatography is rare. Recognizing the presence of free air, which outlines the right kidney, is essential for its early diagnosis and appropriate management.

  15. Retrograde transport of toxins across the endoplasmic reticulum membrane.

    PubMed

    Lord, J M; Deeks, E; Marsden, C J; Moore, K; Pateman, C; Smith, D C; Spooner, R A; Watson, P; Roberts, L M

    2003-12-01

    Several protein toxins, including the A chain of the plant protein ricin (RTA), enter mammalian cells by endocytosis and catalytically modify cellular components to disrupt essential cellular processes. In the case of ricin, the process inhibited is protein synthesis. In order to reach their cytosolic substrates, several toxins undergo retrograde transport to the ER (endoplasmic reticulum) before translocating across the ER membrane. To achieve this export, these toxins exploit the ERAD (ER-associated protein degradation) pathway but must escape, at least in part, the normal degradative fate of ERAD substrates in order to intoxicate the cell. Toxins that translocate from the ER have an unusually low lysine content that reduces the likelihood of ubiquitination and ubiquitin-mediated proteasomal degradation. We have changed the two lysyl residues normally present in RTA to arginyl residues. Their replacement in RTA did not have a significant stabilizing effect on the protein, suggesting that the endogenous lysyl residues are not sites for ubiquitin attachment. However, when four additional lysyl residues were introduced into RTA in a way that did not compromise the activity, structure or stability of the toxin, degradation was significantly enhanced. Enhanced degradation resulted from ubiquitination that predisposed the toxin to proteasomal degradation. Treatment with the proteasomal inhibitor lactacystin increased the cytotoxicity of the lysine-enriched RTA to a level approaching that of wild-type RTA.

  16. Role of endoscopic retrograde cholangiopancreatography after orthotopic liver transplantation.

    PubMed Central

    O'Connor, H J; Vickers, C R; Buckels, J A; McMaster, P; Neuberger, J M; West, R J; Elias, E

    1991-01-01

    Twelve of 178 (7%) liver transplant patients underwent endoscopic retrograde cholangiopancreatography (ERCP) after transplantation. The indications for ERCP were persistent or late onset cholestasis, recurrent cholangitis, and suspected biliary leaks or strictures. The time between transplantation and ERCP ranged from 44 to 330 days (median 153 days). Biliary complications diagnosed by ERCP included biliary sludge in the form of casts, calculi, or debris (n = 7); bile leaks (n = 2); a biliary stricture (n = 1), and complete biliary obstruction (n = 1). One patient had a normal cholangiogram after transplantation. Biliary sludge was detected by ultrasound before ERCP in only one of six patients. Eight patients underwent endoscopic papillotomy, followed by clearance of biliary sludge in four and dilatation of a biliary stricture in one. Two patients bled after papillotomy but neither required surgical intervention. At a median follow up of 1.2 years (range 0.5-2.8 years), nine patients are well and three have died. ERCP provides both accurate diagnosis of biliary complications after liver transplantation and treatment that obviates the need for additional surgery in selected patients. Images Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 PMID:2026341

  17. Radiation exposure to personnel performing endoscopic retrograde cholangiopancreatography

    PubMed Central

    Naidu, L; Singhal, S; Preece, D; Vohrah, A; Loft, D

    2005-01-01

    Background: Endoscopic retrograde cholangiopancreatography (ERCP) relies on the use of ionising radiation but risks to operator and patient associated with radiation exposure are unclear. The aim of this prospective study was to estimate the radiation dose received by personnel performing fluoroscopic endoscopic procedures, mainly ERCP. Methods: Consecutive procedures over a two month period were included. The use of thermoluminescent dosimeters to measure radiation exposure to the abdomen, thyroid gland, and hands of the operator permitted an estimation of the annual whole body effective dose equivalent. Results: During the study period 66 procedures (61 ERCP) were performed and the estimated annual whole body effective dose equivalent received by consultant operators ranged between 3.35 and 5.87 mSv. These values are similar to those received by patients undergoing barium studies and equate to an estimated additional lifetime fatal cancer risk between 1 in 7000 and 1 in 3500. While within legal safety limits for radiation exposure to personnel, these doses are higher than values deemed acceptable for the general public. Conclusions: It is suggested that personnel as well as patients may be exposed to significant values of radiation during ERCP. The study emphasises the need to carefully assess the indication for, and to use measures that minimise radiation exposure during any fluoroscopic procedure. PMID:16210465

  18. Subcapsular hepatic haematoma after endoscopic retrograde cholangiopancreatography: an unusual case.

    PubMed

    Fei, Bao-Ying; Li, Cai-Hong

    2013-03-07

    Subcapsular hepatic haematoma is a rare complication of endoscopic retrograde cholangiopancreatography (ERCP), and there are few reports about this unusual complication worldwide. The primary symptom of most cases reported in the literature is abdominal pain. We report an unusual case with the primary symptom of fever. A 56-year-old man who had a six-month history of recurrent episodes of upper abdominal pain was diagnosed with a common bile duct stone by magnetic resonance cholangiopancreatography. Endoscopic biliary sphincterotomy was performed, and stones from the common bile duct were successfully extracted with a basket. The patient had a persistent fever after ERCP, and treatment with intravenous antibiotics was unsuccessful. Computed tomography showed a 13 cm × 6 cm subcapsular hepatic haematoma filled with air and liquid on the surface of the right hepatic lobe. The patient was successfully treated with peritoneal drainage under B-ultra guidance. Subcapsular liver haematoma should be considered when hard-to- explain symptoms persist in the early period after ERCP. Percutaneous drainage is an effective treatment.

  19. Early Results of Retrograde Transpopliteal Angioplasty of Iliofemoral Lesions

    SciTech Connect

    Saha, Saumitra; Gibson, Matthew; Magee, Timothy R.; Galland, Robert B.; Torrie, E. Peter H.

    2001-12-15

    Purpose: To assess whether the retrograde transpopliteal approach is a safe, practical and effective alternative to femoral puncture for percutaneous transluminal angioplasty (PTA).Methods: Forty PTAs in 38 patients were evaluated. Intentional subintimal recanalization was performed in 13 limbs. Ultrasound evaluation of the popliteal fossa was carried out 30 min and 24 hr post procedurally in the first 10 patients to exclude local complications. All patients had a follow-up of at least 6 weeks.Results: The indication for PTA was critical ischemia in seven limbs and disabling claudication in the remainder.Stenoses (single or multiple) were present in 24 and occlusion in 15.The superficial femoral artery (SFA) was the commonest segment affected(36) followed by common femoral artery (CFA) in four and iliac artery in four. Technical success was achieved in 38 of 39 limbs where angioplasty was carried out. In one limb no lesion was found.Immediate complications were distal embolization in two and thrombosis in one. None of these required immediate surgery. There were no puncture site hematomas or popliteal arteriovenous fistulae.Symptomatic patency at 6 weeks was 85%. Further reconstructive surgery was required in three limbs and amputation in two.Conclusion: The transpopliteal approach has a high technical success rate and a low complication rate with a potential to develop into an outpatient procedure. It should be considered for flush SFA occulsions or iliac disease with tandem CFA/SFA disease where the contralateral femoral approach is often technically difficult.

  20. Retrograde dacryocystography (RDC) utilizing a round-tipped needle.

    PubMed

    Kosaka, Masaaki; Kamiishi, Hiroshi

    2001-09-01

    Because the application of conventional anterograde dacryocystography has been restricted in cases with an intact lacrimal punctum, the indications are rather limited. The authors developed a new method for retrograde dacryocystography (RDC) using a hand-made round-tipped needle inserted directly into the orifice of the nasolacrimal duct. A 60 mm long aluminum tube (3 mm in diameter) was used to prepare the round-tipped needle. The distal portion of the tube was bent to an angle of about 80 degrees. The tip was then coated with synthetic resin adhesive to make it round. Following the insertion of the round-tipped needle directly into the inferior meatus, the tip was moved back and forth to find the orifice without visual observation. The complete insertion of the tip of the needle into the nasolacrimal duct was recognized by a fixed sensation of the tip. Contrast medium was then injected, and PA radiography was carried out. In the present paper, the authors report the usefulness of RDC, which is applicable even in cases of injury or obstruction in the upper lacrimal system. In 16 of 20 patients, the quality of the RDC images was judged as excellent. RDC can be carried out within a few seconds after acquiring the technical skills, and is thought to be a useful method, especially in cases of upper lacrimal injury.

  1. Management of endoscopic retrograde cholangiopancreatography-related perforations

    PubMed Central

    Kim, Byung Seup; Kim, In-Gyu; Ryu, Byoung Yoon; Kim, Jong Hyeok; Yoo, Kyo Sang; Baik, Gwang Ho; Kim, Jin Bong

    2011-01-01

    Purpose The purpose of this study is to analyze the treatment strategies of patients with endoscopic retrograde cholangiopancreatography (ERCP)-related perforations. This is a retrospective study. Methods We experienced 13 perforations associated with ERCP. We reviewed the medical recordsand classified ERCP-related perforations according to mechanism of injury in terms of perforating device. Injury by endoscopic tip or insertion tube was classified as type I, injury by cannulation catheter or sphincterotomy knife as type II, and injury by guidewire as type III. Results Of four type I injuries, one case was managed by conservative management after primary closure with a hemoclip during ERCP. The other three patients underwent surgical treatments such as primary closure orpancreatico-duodenectomy. Of five type II injuries, two patients underwent conservative management and the other three cases were managed by surgical treatment such as duodenojejunostomy, duodenal diverticulization and pancreatico-duodenectomy. Of four type III injuries, three patients were managed conservatively and the remaining patient was managed by T-tube choledochostomy. Conclusion Type I injuries require immediate surgical management after EPCP or immediate endoscopic closure during ERCP whenever possible. Type II injuries require surgical or conservative treatment according to intra- and retro-peritoneal dirty fluid collection findings following radiologic evaluation. Type III injuries almost always improve after conservative treatment with endoscopic nasobilliary drainage. PMID:22066121

  2. Miniperc and retrograde intrarenal surgery: when and how?

    PubMed

    Ramón de Fata, F; Hauner, K; Andrés, G; Angulo, J C; Straub, M

    2015-09-01

    Extracorporeal shock wave lithotripsy (ESWL) and percutaneous nephrolithotomy (PCNL) are consolidated procedures for the treatment of kidney stones; however, their primary weak points are the lower efficacy of ESWL, especially for lower calyx stones, and the morbidity of PCNL resulting from the creation and dilation of the percutaneous trajectory. The increasing miniaturization of percutaneous surgery instrumentation and the development of retrograde intrarenal surgery (RIRS) are recent innovations. A structured nonsystematic review was conducted through a literature search of articles published between 1997 and 2013, using the terms kidney stones, miniperc, mini-PCNL, RIRS and flexible ureteroscopy in the PubMed, Google Scholar and Scopus databases. RIRS requires greater surgical time, several procedures for voluminous stones and higher hospital costs, due in part to the relative fragility of the instruments. On the other hand, miniperc requires a longer hospital stay, an increased need for postoperative analgesia and a greater reduction in hemoglobin levels, although these do not translate into an increased rate of transfusions. The current treatment of kidney stones uses minimally invasive procedures such as miniperc and RIRS. The 2 procedures are equivalent in terms of efficacy (stone clearance) and are associated with minimal complications. Comparative prospective studies are necessary to determine the position of each of these techniques in the treatment of kidney stones. In our experience, the 2 techniques are complementary and should be part of the current urological therapeutic arsenal. Copyright © 2014 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. [Knowing an infrequent complication of endoscopic retrograde cholangiopancreatography].

    PubMed

    Barreda Cevasco, Luis; Targarona Modena, Javier; Marcos Enriquez, Juan Carlos; Arroyo Basto, Carlos; Morón, Elizabeth

    2017-01-01

    Describe the clinical and tomographic characteristics in relation to the extra peritoneal distribution of collections and air in patients with periampullary perforation after performing endoscopic retrograde cholangiopancreatography (ERCP) with or without sphincterotomy. Observational, descriptive study in patients with periampullary perforation after ERCP with or without sphincterotomy, treated in the Pancreas Surgery Service at Edgardo Rebagliati Martins Hospital, Lima, Peru between January 2013 and January 2015. Ten patients with periampullary perforation after ERCP were included. 40% were male. The mean age was 47.2 years. 100% showed abdominal pain, fever 70%, 60% had jaundice, oral intolerance and vomiting. In 100% of cases the description of the procedure was for choledocolithiasis. Difficult cannulation is described in 80% of cases. Air or fluid was found in 90% in the right anterior pararenal space and the right perirenal, and the place where air or liquid is distributed less frequently was right extraperitoneal pelvis with 20%, in no caserevealed air in the mediastinum. The finding of a liquid collection and / or air in the retroperitoneal space right after ERCP without further involvement of the pancreatic gland should make us think of periampullary perforation, especially if you are in the right anterior pararenal space and perirenal space. This entity we call bilioretroperitoneo.

  4. Failed Ventriculoperitoneal Shunt: Is Retrograde Ventriculosinus Shunt a Reliable Option?

    PubMed

    Oliveira, Matheus Fernandes de; Teixeira, Manoel Jacobsen; Reis, Rodolfo Casimiro; Petitto, Carlo Emanuel; Gomes Pinto, Fernando Campos

    2016-08-01

    Currently, the treatment of hydrocephalus is mainly carried out through a ventriculoperitoneal shunt (VPS) insertion. However, in some cases, there may be surgical revisions and requirement of an alternative distal site for shunting. There are several described distal sites, and secondary options after VPS include ventriculopleural and ventriculoatrial shunt, which have technical difficulties and harmful complications. In this preliminary report we describe our initial experience with retrograde ventriculosinus shunt (RVSS) after failed VPS. In 3 consecutive cases we applied RVSS to treat hydrocephalus in shunt-dependent patients who had previously undergone VPS revision and in which peritoneal space was full of adhesions and fibrosis. RVSS was performed as described by Shafei et al., with some modifications to each case. All 3 patients kept the same clinical profile after RVSS, with no perioperative or postoperative complications. However, revision surgery was performed in the first operative day in 1 out of 3 patients, in which the catheter was not positioned in the superior sagittal sinus. We propose that in cases where VPS is not feasible, RVSS may be a safe and applicable second option. Nevertheless, the long-term follow-up of patients and further learning curve must bring stronger evidence. Copyright © 2016 Elsevier Inc. All rights reserved.

  5. Statistical mechanical description of supercritical fluid extraction and retrograde condensation

    NASA Astrophysics Data System (ADS)

    Park, S. J.; Kwak, T. Y.; Mansoori, G. A.

    1987-07-01

    The phenomena of supercritical fluid extraction (SFE) and its reverse effect, which is known as retrograde condensation (RC), have found new and important applications in industrial separation of chemical compounds and recovery and processing of natural products and fossil fuels. Full-scale industrial utilization of SFE/RC processes requires knowledge about thermodynamic and transport characteristics of the asymmetric mixtures involved and the development of predictive modeling and correlation techniques for performance of the SFE/RC system under consideration. In this report, through the application of statistical mechanical techniques, the reasons for the lack of accuracy of existing predictive approaches are described and they are improved. It is demonstrated that these techniques also allow us to study the effect of mixed supercritical solvents on the solubility of heavy solutes (solids) at different compositions of the solvents, pressures, and temperatures. Fluid phase equilibrium algorithms based on the conformal solution van der Waals mixing rules and different equations of state are presented for the prediction of solubilities of heavy liquid in supercritical gases. It is shown that the Peng-Robinson equation of state based on conformal solution theory can predict solubilites of heavy liquid in supercritical gases more accurately than the van der Waals and Redlich-Kwong equations of state.

  6. Characterization of the human GARP (Golgi associated retrograde protein) complex

    SciTech Connect

    Liewen, Heike; Meinhold-Heerlein, Ivo; Oliveira, Vasco; Schwarzenbacher, Robert; Luo Guorong; Wadle, Andreas; Jung, Martin; Pfreundschuh, Michael; Stenner-Liewen, Frank . E-mail: stenlie@t-online.de

    2005-05-15

    The Golgi associated retrograde protein complex (GARP) or Vps fifty-three (VFT) complex is part of cellular inter-compartmental transport systems. Here we report the identification of the VFT tethering factor complex and its interactions in mammalian cells. Subcellular fractionation shows that human Vps proteins are found in the smooth membrane/Golgi fraction but not in the cytosol. Immunostaining of human Vps proteins displays a vesicular distribution most concentrated at the perinuclear envelope. Co-staining experiments with endosomal markers imply an endosomal origin of these vesicles. Significant accumulation of VFT complex positive endosomes is found in the vicinity of the Trans Golgi Network area. This is in accordance with a putative role in Golgi associated transport processes. In Saccharomyces cerevisiae, GARP is the main effector of the small GTPase Ypt6p and interacts with the SNARE Tlg1p to facilitate membrane fusion. Accordingly, the human homologue of Ypt6p, Rab6, specifically binds hVps52. In human cells, the 'orphan' SNARE Syntaxin 10 is the genuine binding partner of GARP mediated by hVps52. This reveals a previously unknown function of human Syntaxin 10 in membrane docking and fusion events at the Golgi. Taken together, GARP shows significant conservation between various species but diversification and specialization result in important differences in human cells.

  7. Endoscopic retrograde cholangiopancreatography in patients with surgically altered gastrointestinal anatomy.

    PubMed

    Amer, Syed; Horsley-Silva, Jennifer L; Menias, Christine O; Pannala, Rahul

    2015-10-01

    Endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered upper gastrointestinal anatomy, such as Roux-en-Y gastric bypass (RYGB), can be more challenging compared to those with a normal anatomy. Detailed assessment of cross-sectional imaging features by the radiologist, especially the pancreaticobiliary anatomy, strictures, and stones, is very helpful to the endoscopist in planning the procedure. In addition, any information on enteral anastomoses (for e.g., gastrojejunal strictures and afferent limb obstruction) is also very useful. The endoscopist should review the operative note to understand the exact anatomy prior to procedure. RYGB, which is performed for medically complicated obesity, is the most commonly encountered altered anatomy ERCP procedure. Other situations include patients who have had a pancreaticoduodenectomy or a hepaticojejunostomy. Balloon-assisted deep enteroscopy (single and double-balloon enteroscopy) or rotational endoscopy is often used to traverse the length of the intestine to reach the papilla. In addition, ERCP in these patients is further challenging due to the oblique orientation of the papilla relative to the forward viewing endoscope and the limited enteroscopy-length therapeutic accessories that are currently available. Overall, reported therapeutic success is approximately 70-75% with a complication rate of 3-4%. Alternative approaches include percutaneous transhepatic cholangiography, laparoscopy-assisted ERCP, or surgery. Given the complexity, ERCP in patients with surgically altered anatomy should be performed in close collaboration with body imagers, interventional radiology, and surgical services.

  8. Retrograde angiography and the risk of arteriovenous fistula perforation.

    PubMed

    Salman, Loay; Asif, Arif; Beathard, Gerald A

    2009-01-01

    Assessment of the inflow segment of an arteriovenous fistula is mandatory for optimum access evaluation. Retrograde angiography (RA) is routinely used to image this region of the access system. Traditionally, RA is performed by manually occluding the outflow track of an arteriovenous fistula (AVF) and forcing the radiocontrast into the inflow segment against arterial pressure. While this technique is largely successful in visualizing the juxta-anastomotic region, anastomosis and a portion of the feeding artery, the approach carries a potential risk of vascular rupture between the occluded portion of the fistula and the anastomosis. This article presents six cases of fistulas that suffered vascular rupture during RA. In three cases, vascular damage occurred prior to the application of angioplasty. The remaining cases suffered perforation after angioplasty. Balloon tamponade was successful in salvaging two fistulas. Another AVF with a perforation did not require any intervention to maintain flow. The complication was successfully managed in one AVF by the insertion of an endovascular stent graft. Two fistulas were lost due to vascular damage. This report demonstrates that RA performed by occluding the outflow track of an AVF to assess the results of angioplasty of an inflow stenosis can result in vascular rupture. There is a risk of such adversity even before the application of angioplasty in this region. It is suggested that the first of these be avoided and the latter be done with care.

  9. Intraparenchymal hematoma as a late complication of retrograde intrarenal surgery.

    PubMed

    Yahsi, Sedat; Tonyali, Senol; Ceylan, Cavit; Yildiz, Kenan Y; Ozdal, Levent

    2017-01-01

    A 34 year-old woman was admitted to our hospital with left flank pain. A non-contrast enhanced computerized tomography (NCCT) revealed a 1.5x2cm left proximal ureter stone. Patient was scheduled for ureterorenoscopy (URS) and stone removal. She was submitted to retrograde intrarenal surgery (RIRS). At the postoperative 1st day, the patient began to suffer from left flank pain. A NCCT was taken, which revealed a subcapsular hematoma and perirenal fluid. The patient was managed conservatively with intravenous fluid, antibiotic and non-steroidal anti-inflammatory drug therapy and was discharged at the postoperative 6th day. Two weeks after the discharge the patient was admitted to emergency department with severe left flank pain, palpitation and malaise. KUB (kidney-ureter-bladder) radiography showed double-J stent (DJS) to be repositioned to the proximal ureter. Patient was evaluated with contrast enhanced CT which revealed an 8cm intraparenchymal hematoma/abscess in the middle part of the kidney. A percutaneous drainage catheter was inserted into the collection. The percutaneous drainage catheter and the DJS were removed at the 10th day of second hospitalization. RIRS surgery is an effective and feasible choice for renal stones with high success and acceptable complication rates. However, clinician should be alert to possible complications.

  10. Retrograde guidewire fracture complicated with pericardial tamponade in chronic total occlusive coronary lesion.

    PubMed

    Park, Sang-Ho; Rha, Seung-Woon; Her, Keun

    2015-10-01

    Along with various coronary devices progress, there is a now growing trend to percutaneous coronary intervention for chronic total occlusion (CTO). However, the risk of guidewire fracture rate might be increased in complex lesion such as tortuous, calcific lesion or retrograde route. We report a case of successful surgical removal of fractured and entrapped guidewire in a septal channel during retrograde CTO intervention in a patient complicated with pericardial tamponade by delayed penetration of broken guidewire into pericardium.

  11. Surgical Repair of Retrograde Type A Aortic Dissection after Thoracic Endovascular Aortic Repair

    PubMed Central

    Kim, Chang-Young; Kim, Yeon Soo; Ryoo, Ji Yoon

    2014-01-01

    It is expected that the stent graft will become an alternative method for treating aortic diseases or reducing the extent of surgery; therefore, thoracic endovascular aortic repair has widened its indications. However, it can have rare but serious complications such as paraplegia and retrograde type A aortic dissection. Here, we report a surgical repair of retrograde type A aortic dissection that was performed after thoracic endovascular aortic repair. PMID:24570865

  12. Pulmonary arterial intimal sarcoma with retrograde extension: report of a case and review of literature.

    PubMed

    Vaideeswar, Pradeep; Pillai, Raji

    2013-01-01

    Most of the pulmonary arterial sarcomas arise from multi-potential mesenchymal intimal cells and are designated as intimal sarcomas. These tumors grow in the direction of blood flow into peripheral arteries producing clinical features mimicking pulmonary thromboembolism. Retrograde extension is rare. We report one such case of intimal sarcoma that had a retrograde extension into the right ventricular outflow tract, and review such a presentation in the last ten years.

  13. Emergency presentation of retrograde intussusception as a late complication of gastric bypass

    PubMed Central

    Pande, R; Fraser, I; Harmston, C

    2012-01-01

    Retrograde intussusception is a rare complication of a Roux-en-Y gastric bypass. With the rising number of gastric bypass operations being performed in the UK, the incidence of retrograde intussusception is likely to increase. We report the first case in the UK and highlight its insidious presentation and the importance of considering intussusception in any patient with a history of a Roux-en-Y gastric bypass. PMID:22507706

  14. Successful Balloon-Occluded Retrograde Transvenous Obliteration for Gastric Varix Mainly Draining into the Pericardiophrenic Vein

    SciTech Connect

    Kageyama, Ken; Nishida, N. Matsui, H.; Yamamoto, A.; Nakamura, K.; Miki, Y.

    2012-02-15

    Two cases of gastric varices were treated by balloon-occluded retrograde transvenous obliteration via the pericardiophrenic vein at our hospital, and both were successful. One case developed left hydrothorax. Gastric varices did not bled and esophageal varices were not aggravated in both cases for 24-30 months thereafter. These outcomes indicate the feasibility of balloon-occluded retrograde transvenous obliteration via the pericardiophrenic vein.

  15. Retrogradation of Waxy Rice Starch Gel in the Vicinity of the Glass Transition Temperature

    PubMed Central

    Charoenrein, Sanguansri; Udomrati, Sunsanee

    2013-01-01

    The retrogradation rate of waxy rice starch gel was investigated during storage at temperatures in the vicinity of the glass transition temperature of a maximally concentrated system (Tg′), as it was hypothesized that such temperatures might cause different effects on retrogradation. The Tg′ value of fully gelatinized waxy rice starch gel with 50% water content and the enthalpy of melting retrograded amylopectin in the gels were investigated using differential scanning calorimetry. Starch gels were frozen to −30°C and stored at 4, 0, −3, −5, and −8°C for 5 days. The results indicated that the Tg′ value of gelatinized starch gel annealed at −7°C for 15 min was −3.5°C. Waxy rice starch gels retrograded significantly when stored at 4°C with a decrease in the enthalpy of melting retrograded starch in samples stored for 5 days at −3, −5, and −8°C, respectively, perhaps due to the more rigid glass matrix and less molecular mobility facilitating starch chain recrystallization at temperatures below Tg′. This suggests that retardation of retrogradation of waxy rice starch gel can be achieved at temperature below Tg′. PMID:26904602

  16. Clathrin adaptor epsinR is required for retrograde sorting on early endosomal membranes.

    PubMed

    Saint-Pol, Agnès; Yélamos, Belén; Amessou, Mohamed; Mills, Ian G; Dugast, Marc; Tenza, Danièle; Schu, Peter; Antony, Claude; McMahon, Harvey T; Lamaze, Christophe; Johannes, Ludger

    2004-04-01

    Retrograde transport links early/recycling endosomes to the trans-Golgi network (TGN), thereby connecting the endocytic and the biosynthetic/secretory pathways. To determine how internalized molecules are targeted to the retrograde route, we have interfered with the function of clathrin and that of two proteins that interact with it, AP1 and epsinR. We found that the glycosphingolipid binding bacterial Shiga toxin entered cells efficiently when clathrin expression was inhibited. However, retrograde transport of Shiga toxin to the TGN was strongly inhibited. This allowed us to show that for Shiga toxin, retrograde sorting on early/recycling endosomes depends on clathrin and epsinR, but not AP1. EpsinR was also involved in retrograde transport of two endogenous proteins, TGN38/46 and mannose 6-phosphate receptor. In conclusion, our work reveals the existence of clathrin-independent and -dependent transport steps in the retrograde route, and establishes a function for clathrin and epsinR at the endosome-TGN interface.

  17. New concept for CTO recanalization using controlled antegrade and retrograde subintimal tracking: the CART technique.

    PubMed

    Surmely, Jean-François; Tsuchikane, Etsuo; Katoh, Osamu; Nishida, Yasunori; Nakayama, Mutsuo; Nakamura, Shigeru; Oida, Akitsugu; Hattori, Eijiro; Suzuki, Takahiko

    2006-07-01

    To demonstrate the safety and feasibility of a new concept for CTO recanalization using a controlled antegrade and retrograde subintimal tracking technique (CART technique). A successful percutaneous recanalization of chronic coronary occlusions results in improved survival, as well as enhanced left ventricular function, reduction in angina, and improved exercise tolerance. However, successful recanalization of CTOs is still not optimal, and needs further improvements. Ten patients with a CTO underwent the CART procedure. This technique combines the simultaneous use of the antegrade and retrograde approaches. A subintimal dissection is created antegradely and retrogradely, which allows the operator to limit the extension of the subintimal dissection in the CTO portion. A retrograde approach means that the occlusion site is approached in a retrograde fashion through the best collateral channel from any other patent coronary artery. The occlusion site was located in the RCA in 9 patients, and in the LAD in 1 patient. CTO duration varied from 7 to 84 months. Vessel recanalization was achieved in all patients. In all cases, the subintimal dissection was limited to the CTO region. No complications occurred in the collateral channel used for the retrograde approach. There were no in-hospital major adverse cardiac events. The CART technique is feasible, safe, and has a high success rate.

  18. Impaired motoneuronal retrograde transport in two models of SBMA implicates two sites of androgen action.

    PubMed

    Kemp, Michael Q; Poort, Jessica L; Baqri, Rehan M; Lieberman, Andrew P; Breedlove, S Marc; Miller, Kyle E; Jordan, Cynthia L

    2011-11-15

    Spinal and bulbar muscular atrophy (SBMA) impairs motor function in men and is linked to a CAG repeat mutation in the androgen receptor (AR) gene. Defects in motoneuronal retrograde axonal transport may critically mediate motor dysfunction in SBMA, but the site(s) where AR disrupts transport is unknown. We find deficits in retrograde labeling of spinal motoneurons in both a knock-in (KI) and a myogenic transgenic (TG) mouse model of SBMA. Likewise, live imaging of endosomal trafficking in sciatic nerve axons reveals disease-induced deficits in the flux and run length of retrogradely transported endosomes in both KI and TG males, demonstrating that disease triggered in muscle can impair retrograde transport of cargo in motoneuron axons, possibly via defective retrograde signaling. Supporting the idea of impaired retrograde signaling, we find that vascular endothelial growth factor treatment of diseased muscles reverses the transport/trafficking deficit. Transport velocity is also affected in KI males, suggesting a neurogenic component. These results demonstrate that androgens could act via both cell autonomous and non-cell autonomous mechanisms to disrupt axonal transport in motoneurons affected by SBMA.

  19. Post-Golgi anterograde transport requires GARP-dependent endosome-to-TGN retrograde transport.

    PubMed

    Hirata, Tetsuya; Fujita, Morihisa; Nakamura, Shota; Gotoh, Kazuyoshi; Motooka, Daisuke; Murakami, Yoshiko; Maeda, Yusuke; Kinoshita, Taroh

    2015-09-01

    The importance of endosome-to-trans-Golgi network (TGN) retrograde transport in the anterograde transport of proteins is unclear. In this study, genome-wide screening of the factors necessary for efficient anterograde protein transport in human haploid cells identified subunits of the Golgi-associated retrograde protein (GARP) complex, a tethering factor involved in endosome-to-TGN transport. Knockout (KO) of each of the four GARP subunits, VPS51-VPS54, in HEK293 cells caused severely defective anterograde transport of both glycosylphosphatidylinositol (GPI)-anchored and transmembrane proteins from the TGN. Overexpression of VAMP4, v-SNARE, in VPS54-KO cells partially restored not only endosome-to-TGN retrograde transport, but also anterograde transport of both GPI-anchored and transmembrane proteins. Further screening for genes whose overexpression normalized the VPS54-KO phenotype identified TMEM87A, encoding an uncharacterized Golgi-resident membrane protein. Overexpression of TMEM87A or its close homologue TMEM87B in VPS54-KO cells partially restored endosome-to-TGN retrograde transport and anterograde transport. Therefore GARP- and VAMP4-dependent endosome-to-TGN retrograde transport is required for recycling of molecules critical for efficient post-Golgi anterograde transport of cell-surface integral membrane proteins. In addition, TMEM87A and TMEM87B are involved in endosome-to-TGN retrograde transport.

  20. Real-time Visualization and Quantification of Retrograde Cardioplegia Delivery using Near Infrared Fluorescent Imaging

    PubMed Central

    Rangaraj, Aravind T.; Ghanta, Ravi K.; Umakanthan, Ramanan; Soltesz, Edward G.; Laurence, Rita G.; Fox, John; Cohn, Lawrence H.; Bolman, R. M.; Frangioni, John V.; Chen, Frederick Y.

    2009-01-01

    Background and Aim of the Study Homogeneous delivery of cardioplegia is essential for myocardial protection during cardiac surgery. Presently, there exist no established methods to quantitatively assess cardioplegia distribution intraoperatively and determine when retrograde cardioplegia is required. In this study, we evaluate the feasibility of near infrared (NIR) imaging for real-time visualization of cardioplegia distribution in a porcine model. Methods A portable, intraoperative, real-time NIR imaging system was utilized. NIR fluorescent cardioplegia solution was developed by incorporating indocyanine green (ICG) into crystalloid cardioplegia solution. Real-time NIR imaging was performed while the fluorescent cardioplegia solution was infused via the retrograde route in 5 ex-vivo normal porcine hearts and in 5 ex-vivo porcine hearts status post left anterior descending (LAD) coronary artery ligation. Horizontal cross-sections of the hearts were obtained at proximal, middle, and distal LAD levels. Videodensitometry was performed to quantify distribution of fluorophore content. Results The progressive distribution of cardioplegia was clearly visualized with NIR imaging. Complete visualization of retrograde distribution occurred within 4 minutes of infusion. Videodensitometry revealed that retrograde cardioplegia primarily distributed to the left ventricle and anterior septum. In hearts with LAD ligation, antegrade cardioplegia did not distribute to the anterior left ventricle. This deficiency was compensated for with retrograde cardioplegia supplementation. Conclusions Incorporation of ICG into cardioplegia allows real-time visualization of cardioplegia delivery via NIR imaging. This technology may prove useful in guiding intraoperative decisions pertaining to when retrograde cardioplegia is mandated. PMID:19016995

  1. Retrograde reactions in coal processing: The behavior of ether and sulfide model compounds

    SciTech Connect

    Buchanan, A.C. III; Britt, P.F.; Skeen, J.T.

    1997-04-01

    Retrograde reactions that produce more refractory molecular structures are undesirable in coal liquefaction. The authors previously found that restricted mass transport, induced by immobilization on a silica support, promotes retrograde reactions for 1,2-diphenylethane (C{sub 6}H{sub 5}CH{sub 2}CH{sub 2}C{sub 6}H{sub 5}) by both skeletal rearrangement and ring growth (cyclization-dehydrogenation) pathways involving free-radical intermediates. They are now examining the influence of heteroatoms on the retrograde pathways for the corresponding surface-immobilized ether (C{sub 6}H{sub 5}OCH{sub 2}C{sub 6}H{sub 5}) and sulfide (C{sub 6}H{sub 5}SCH{sub 2}C{sub 6}H{sub 5}) model compounds at 275--350 C. Cyclization-dehydrogenation pathways are not detected for either model compound. However, retrograde skeletal rearrangements involving 1,2-phenyl shifts in C{sub 6}H{sub 5}XCH{center_dot}C{sub 6}H{sub 5} (X = O,S) are found to be significant under restricted diffusion, and for X = O, radical coupling at ring carbons to form benzylphenols is also observed as a major pathway. For surface-immobilized benzyl phenyl ether, the two retrograde processes account for ca. 50% of the thermolysis products, and also generate reactive hydroxyl and keto functionalities that can be involved in additional retrograde reactions.

  2. Successful treatment of retrograde ejaculation with sperm recovered from bladder washings. A report of two cases.

    PubMed

    Silva, P D; Larson, K M; Van Every, M J; Silva, D E

    2000-11-01

    Retrograde ejaculation causes < 2% of male infertility but is the leading cause of aspermia. The incidence of retrograde ejaculation is increasing due to the aggressiveness of modern urologic cancer surgery and an increase in diabetes mellitus. Generally, the only adverse effect is on fertility. Various approaches have been proposed for treatment, ranging from insemination with sperm-rich urine obtained after masturbation to intracytoplasmic sperm injection (ICSI). We used a protocol involving bladder washing. Case 1 involved a man with retrograde ejaculation secondary to a successful right orchiectomy and retroperitoneal lymph node dissection for stage B1 embryonal cell carcinoma. He was treated with bladder washing and intrauterine insemination. He fathered three children from six insemination cycles. Case 2 involved a man with idiopathic retrograde ejaculation and a wife with ovulatory dysfunction. He received treatment similar to that in case 1 and fathered one child from two insemination cycles. Larger studies need to be done specifically comparing treatments. Our method resulted in four normal infants in two couples over eight total insemination cycles and, taken together with other results from the literature, seems a good choice for clinicians who are treating retrograde ejaculation for the first time. We agree with others who have recommended that in vitro fertilization/ICSI not be the first step for treating the usual couples with retrograde ejaculation.

  3. Ureteroscopy-assisted retrograde nephrostomy for lower calyx calculi in horseshoe kidney: two case reports.

    PubMed

    Kawahara, Takashi; Ito, Hiroki; Terao, Hideyuki; Tanaka, Katsuyuki; Ogawa, Takehiko; Uemura, Hiroji; Kubota, Yoshinobu; Matsuzaki, Junichi

    2012-07-10

    We previously reported on the effectiveness of ureteroscopy-assisted retrograde nephrostomy during percutaneous nephrolithotomy and report two cases of lower calyx calculi in horseshoe kidney that were successfully treated with ureteroscopy-assisted retrograde nephrostomy. During the ureteroscopy-assisted retrograde nephrostomy procedure, a ureteroscope is advanced in the desired calyx and a Lawson retrograde nephrostomy puncture wire is inserted. The wire is advanced through the calyx to exit the skin. The wire is then used for the percutaneous dilation. Case 1 was a 68-year-old man who was shown on radiography to have left lower calyx calculi (19 × 15mm, 7 × 5mm, and 7 × 3mm) in horseshoe kidney. Case 2 was a 36-year-old woman shown on radiography to have a left lower calyx calculus (10 × 8mm) in horseshoe kidney. Both patients were stone-free after ureteroscopy-assisted retrograde nephrostomy during percutaneous nephrolithotomy. Ureteroscopy-assisted retrograde nephrostomy is a promising procedure for safely and effectively treating lower calyx stones in horseshoe kidney.

  4. Ureteroscopy-assisted retrograde nephrostomy for lower calyx calculi in horseshoe kidney: two case reports

    PubMed Central

    2012-01-01

    Introduction We previously reported on the effectiveness of ureteroscopy-assisted retrograde nephrostomy during percutaneous nephrolithotomy and report two cases of lower calyx calculi in horseshoe kidney that were successfully treated with ureteroscopy-assisted retrograde nephrostomy. During the ureteroscopy-assisted retrograde nephrostomy procedure, a ureteroscope is advanced in the desired calyx and a Lawson retrograde nephrostomy puncture wire is inserted. The wire is advanced through the calyx to exit the skin. The wire is then used for the percutaneous dilation. Case presentation Case 1 was a 68-year-old man who was shown on radiography to have left lower calyx calculi (19 × 15mm, 7 × 5mm, and 7 × 3mm) in horseshoe kidney. Case 2 was a 36-year-old woman shown on radiography to have a left lower calyx calculus (10 × 8mm) in horseshoe kidney. Conclusions Both patients were stone-free after ureteroscopy-assisted retrograde nephrostomy during percutaneous nephrolithotomy. Ureteroscopy-assisted retrograde nephrostomy is a promising procedure for safely and effectively treating lower calyx stones in horseshoe kidney. PMID:22781754

  5. Post-Golgi anterograde transport requires GARP-dependent endosome-to-TGN retrograde transport

    PubMed Central

    Hirata, Tetsuya; Fujita, Morihisa; Nakamura, Shota; Gotoh, Kazuyoshi; Motooka, Daisuke; Murakami, Yoshiko; Maeda, Yusuke; Kinoshita, Taroh

    2015-01-01

    The importance of endosome-to–trans-Golgi network (TGN) retrograde transport in the anterograde transport of proteins is unclear. In this study, genome-wide screening of the factors necessary for efficient anterograde protein transport in human haploid cells identified subunits of the Golgi-associated retrograde protein (GARP) complex, a tethering factor involved in endosome-to-TGN transport. Knockout (KO) of each of the four GARP subunits, VPS51–VPS54, in HEK293 cells caused severely defective anterograde transport of both glycosylphosphatidylinositol (GPI)-anchored and transmembrane proteins from the TGN. Overexpression of VAMP4, v-SNARE, in VPS54-KO cells partially restored not only endosome-to-TGN retrograde transport, but also anterograde transport of both GPI-anchored and transmembrane proteins. Further screening for genes whose overexpression normalized the VPS54-KO phenotype identified TMEM87A, encoding an uncharacterized Golgi-resident membrane protein. Overexpression of TMEM87A or its close homologue TMEM87B in VPS54-KO cells partially restored endosome-to-TGN retrograde transport and anterograde transport. Therefore GARP- and VAMP4-dependent endosome-to-TGN retrograde transport is required for recycling of molecules critical for efficient post-Golgi anterograde transport of cell-surface integral membrane proteins. In addition, TMEM87A and TMEM87B are involved in endosome-to-TGN retrograde transport. PMID:26157166

  6. Endoscopic retrograde cholangiopancreatography in patients with surgically altered anatomy

    PubMed Central

    Wang, Fei; Xu, Boming; Li, Quanpeng; Zhang, Xiuhua; Jiang, Guobing; Ge, Xianxiu; Nie, Junjie; Zhang, Xiuyun; Wu, Ping; Ji, Jie; Miao, Lin

    2016-01-01

    Abstract Endoscopic retrograde cholangiopancreatography (ERCP) in patients with surgically altered anatomy is challenging. Results of ERCP in those patients varied. The aim of our study was to evaluate the safety and effectiveness of various endoscopes-assisted ERCP in patients with surgically altered anatomy. Fifty-two patients with Billroth II reconstruction (group A), 20 patients with subtotal or total gastrectomy with Roux-en-Y anastomosis (group B), 25 patients with pancreatoduodenectomy or Roux-en-Y hepaticojejunostomy reconstruction (group C) were included. Gastroscope, duodenoscope, colonoscope, and double-balloon enteroscope were used. The endoscope insertion success rate of groups A, B, C was 96.2% (50/52), 85.0% (17/20), 80% (20/25), respectively. χ2 test showed that there was no significant difference between the 3 groups (P = 0.068). The mean insertion time was 36.7, 68.4, and 84.0 minutes, respectively. One-way ANOVA showed that the insertion time of group C was significantly longer than that of groups B and C (both P <0.001). The endoscopic cannulation success rates of groups A, B, C were 90%, 82.4%, and 100%, respectively. χ2 test showed that there was no significant difference between the 3 groups (P = 0.144). The mean cannulation time was 19.4, 28.1, and 20.4 minutes, respectively. One-way ANOVA showed that the cannulation time of group B was longer than that of groups A and C (P <0.001, P = 0.001, respectively). In total, 74 patients with successful biliary cannulation achieved the therapeutic goal; thus, the clinical success rate was 76.3% (74/97). Our study showed that ERCP in patients with surgically altered anatomy was safe and feasible. PMID:28033284

  7. Is routine ureteral stenting really necessary after retrograde intrarenal surgery?

    PubMed

    Ozyuvali, Ekrem; Resorlu, Berkan; Oguz, Ural; Yildiz, Yildiray; Sahin, Tolga; Senocak, Cagri; Bozkurt, Omer Faruk; Damar, Erman; Yildirim, Murat; Unsal, Ali

    2015-03-31

    To investigate the situations in which ureteral double-J stent should be used after retrograde intrarenal surgery (RIRS). Patients with no ureteral double-J stent after RIRS constituted Group 1, and those with double- J stent after RIRS constituted Group 2. Patients' age and gender, renal stone characteristics (location and dimension), stone-free status, VAS score 8 hours after surgery, post-procedural renal colic attacks, length of hospitalization, requirement for re-hospitalization, time to rehospitalization and secondary procedure requirements were analyzed. RIRS was performed on 162 renal units. Double-J stent was used in 121 (74.6%) of these after RIRS, but not in the other 41 (25.4%). At radiological monitoring at the first month postoperatively after RIRS, complete stone-free status was determined in 122 (75.3%) renal units, while residual stone was present in 40 (24.6%). No significant differences were observed between the groups in terms of duration of fluoroscopy (p = 0.142), operation (p = 0.108) or hospitalization times (p = 0.798). VAS values determined routinely on the evening of surgery were significantly higher in Group 1 than in Group 2 (p = 0.025). Twenty-eight (17.2%) presentations were made to the emergency clinic due to renal colic within 1 month after surgery. Double-J catheter was present in 24 (85.7%) of these patients. Routine double-J stent insertion after RIRS is not essential since it increases costs, morbidity and operation time.

  8. Otilonium bromide as spasmolytic during endoscopic retrograde cholangiopancreatography.

    PubMed

    Karahan, Ömer; Sevinç, Barış; Okuş, Ahmet; Ay, Serden; Aksoy, Nergis

    2015-08-01

    Endoscopic retrograde cholangiopancreatography (ERCP) is commonly used in both the diagnosis and the treatment of biliary and pancreatic disorders. The aim of this study is to evaluate the effects of OB usage during ERCP on duodenal motility, the tolerability of the procedure (by patients) and the difficulty of the procedure (by the endoscopist). The study was conducted in Konya Training and Research Hospital General Surgery Endoscopy Unit in randomized prospective pattern. The patients were divided into the two groups as spasmolytic and control groups. The procedure was performed under topical anesthesia and sedation. There were 100 cases included into the study (50 cases in each group). The mean duodenal motility score was found to be 1.9 ± 0.5 in the study group and 3 ± 0.6 in the control group. In the study group, the tolerability of the procedure score by the endoscopist was moderate in 16 % and well/very well in 78 % of the cases. On the other hand, in the control group, the scores were poor in 21 %, moderate in 71 %, and well/very well in 24 % of the cases. In terms of patient satisfaction, in study group 42 % of the cases reported the procedure as moderate and 58 % reported as well/very well. However, in the control group 16 % of the cases reported the procedure as poor, 58 % moderate, and 26 % as well/very well. Otilonium bromide is a safe agent with low side effects. It can be used before the ERCP procedure to decrease the duodenal motility. It eases the procedure, moreover, it increases the patients' satisfaction.

  9. Outcome of endoscopic retrograde cholangiopancreatography during live endoscopy demonstrations.

    PubMed

    Ridtitid, Wiriyaporn; Rerknimitr, Rungsun; Treeprasertsuk, Sombat; Kongkam, Pradermchai; Khor, Christopher J L; Kullavanijaya, Pinit

    2012-07-01

    A number of factors may result in lower than expected success rates for endoscopic retrograde cholangiopancreatography (ERCP) performed by overseas experts during live demonstrations (LDs). Stratifying the degree of ERCP difficulty may help in the assessment of procedure outcomes, but no prior reports have done so. This study aimed to compare the success rate and complications of ERCP between procedures performed in live demonstrations and for matched control subjects. From 2004 to 2011, a total of 82 patients who underwent ERCP during live demonstrations at the Endoscopy Unit of King Chulalongkorn Memorial Hospital were reviewed. The control for each patient was a patient admitted to the same ERCP unit with matched indications at the time closest to the demonstration course who had matching gender and techniques in therapeutic interventions during ERCP. The success rates and complications between the two groups were compared based on the grading scale for the degree of difficulty according to Cotton and colleagues. For standard ERCP cases (levels 1-2), the success rate, complication rate, and duration of the procedure (DOP) did not differ significantly. In contrast, the success rate for complex ERCPs (levels 3-4) performed during LD was significantly lower (73% vs. 90%; P = 0.006). The complication rates and DOP were not significantly different (P = 0.31 and 0.23, respectively). The overall success rate was significantly lower for LD procedures than for control procedures (81% vs. 91%; P = 0.02). In this series, the standard ERCP performed during LD was associated with success and complication rates similar to those for the control subjects. Complex ERCP cases were, however, associated with lower success rates than those for the control subjects. A high proportion of complex ERCP cases during live demonstration can influence the overall success rate of ERCPs performed by overseas experts.

  10. Retrograde degeneration of retinal ganglion cells in homonymous hemianopsia

    PubMed Central

    Herro, Angela M; Lam, Byron L

    2015-01-01

    Background The aim of this study was to demonstrate the relationship between topographic reduction in macular ganglion cell complex (GCC) thickness as detected with spectral-domain optical coherence tomography and visual field defects caused by ischemic occipital cortical injury. Methods This study was a retrospective review of all patients who presented to our eye institution between January 2012 and July 2014 with visual field defects secondary to ischemic cortical injury. The visual field defect pattern and mean deviation were analyzed. Retinal nerve fiber layer (RNFL) and macular GCC were both assessed with spectral-domain optical coherence tomography. Patients with any ocular pathology that could affect these measurements were excluded. The topographic relationship of visual field defect to reduction in GCC was specifically analyzed. Results Nine patients met the inclusion criteria. Their average age was 65 (57–73) years; eight were men and six had right hemianopsias. The laterality of the visual field defect was used to assign an affected and unaffected side of analysis for RNFL and GCC layer thickness. A right hemianopsia meant that the nasal fibers of the right eye and temporal fibers of the left eye were assigned as the “affected side”, and the temporal fibers of the right eye and nasal fibers of the left eye were assigned as “unaffected”. There was no statistically significant difference between affected and unaffected RNFL. However, there was a significant difference in GCC layer reduction between the affected and unaffected sides (P=0.029). Conclusion There is evidence of retrograde trans-synaptic retinal ganglion cell loss in patients with homonymous hemianopsias from cortical visual impairment. This relationship is reflected in thinning of the GCC and maintains the topographic relationship of the visual field defect. PMID:26089638

  11. Can Rectal Diclofenac Prevent Post Endoscopic Retrograde Cholangiopancreatography Pancreatitis?

    PubMed

    Lua, Guan Way; Muthukaruppan, Raman; Menon, Jayaram

    2015-10-01

    Non steroidal anti-inflammatory drugs (NSAIDs) have been shown to reduce the incidence of post endoscopic retrograde cholangiopancreatography pancreatitis (PEP). There were various trials using different routes and dosages of NSAIDs but meta-analysis revealed inconsistent results. The aims of this study were to determine the efficacy of rectal diclofenac in preventing PEP and to evaluate any adverse events. This was a randomized, open-label, two-arm, prospective clinical trial. Only patients at high risk of developing PEP were recruited. They received 100 mg rectal diclofenac or no intervention immediately after ERCP. The patients were reviewed 30 days after discharge to evaluate any adverse event. Among 144 recruited patients, 69 (47.9%) received diclofenac and 75 (52.1%) had no intervention. Eleven patients (7.6%) developed PEP, in which seven were from the diclofenac group and four were in the control group. Eight cases of PEP (5.5%) were mild and three cases (2.1%) were moderate. The differences in pancreatitis incidence and severity between both groups were not statistically significant. There were 11 adverse events reported. Clinically significant bleeding happened in four patients (2.8%): one from the diclofenac group and three from the control group. Other events included cholangitis: two patients (2.9%) from the diclofenac group and four (5.3%) from the control group. One patient from the diclofenac group (1.4%) had a perforation which was treated conservatively. In summary, prophylactic rectal diclofenac did not significantly decrease the incidence of PEP among patients at high risk for developing PEP. However, the administration of diclofenac was fairly safe with few clinical adverse events.

  12. Procedure for decellularization of porcine heart by retrograde coronary perfusion.

    PubMed

    Remlinger, Nathaniel T; Wearden, Peter D; Gilbert, Thomas W

    2012-12-06

    Perfusion-based whole organ decellularization has recently gained interest in the field of tissue engineering as a means to create site-specific extracellular matrix scaffolds, while largely preserving the native architecture of the scaffold. To date, this approach has been utilized in a variety of organ systems, including the heart, lung, and liver (1-5). Previous decellularization methods for tissues without an easily accessible vascular network have relied upon prolonged exposure of tissue to solutions of detergents, acids, or enzymatic treatments as a means to remove the cellular and nuclear components from the surrounding extracellular environment(6-8). However, the effectiveness of these methods hinged upon the ability of the solutions to permeate the tissue via diffusion. In contrast, perfusion of organs through the natural vascular system effectively reduced the diffusion distance and facilitated transport of decellularization agents into the tissue and cellular components out of the tissue. Herein, we describe a method to fully decellularize an intact porcine heart through coronary retrograde perfusion. The protocol yielded a fully decellularized cardiac extracellular matrix (c-ECM) scaffold with the three-dimensional structure of the heart intact. Our method used a series of enzymes, detergents, and acids coupled with hypertonic and hypotonic rinses to aid in the lysis and removal of cells. The protocol used a Trypsin solution to detach cells from the matrix followed by Triton X-100 and sodium deoxycholate solutions to aid in removal of cellular material. The described protocol also uses perfusion speeds of greater than 2 L/min for extended periods of time. The high flow rate, coupled with solution changes allowed transport of agents to the tissue without contamination of cellular debris and ensured effective rinsing of the tissue. The described method removed all nuclear material from native porcine cardiac tissue, creating a site-specific cardiac ECM

  13. A possible structure of retrograded maize starch speculated by UV and IR spectra of it and its components.

    PubMed

    Lian, Xijun; Zhang, Kunsheng; Luo, Qingfeng; Wang, Chen; Liu, Xueyan

    2012-01-01

    "Retrogradation" has been used to describe the changes that occur in starch after gelatinization, from an initially amorphous state to a more ordered or crystalline state, which has a significant impact on starch application in food, textiles and materials fields. But mechanism of starch retrogradation is still unclear until now and there is no breakthrough in this area. Here we are speculating a possible structure of retrograded maize starch by UV (binding with iodine) and IR spectra of it and its compositions. We speculate that nucleation of retrograded starch origins from combination of reducing end of amylopectin and non-reducing end of amylose, and retrogradation terminates at combining of non-reducing end of amylopectin and reducing end of amylose. The chain length of resistant digestion retrograded starch should be nearly same. The hydroxyl associated with sixth carbon atoms of glucan must form hydrogen bond with other hydroxyl of starch.

  14. Effects of soy protein hydrolysates on maize starch retrogradation studied by IR spectra and ESI-MS analysis.

    PubMed

    Lian, Xijun; Zhu, Wei; Wen, Yan; Li, Lin; Zhao, Xiaoshuang

    2013-08-01

    Starch retrogradation is the main cause of quality deterioration of starch-containing foods during storage. The purpose of this study is to find out whether certain soy protein polypeptide in hydrolysates will retard maize starch retrogradation. The results show that all soy protein hydrolysates retard maize starch retrogradation to a certain extent. The IR spectra of hydrolysates and the blends of hydrolysates and maize starch show that the polypeptides might act with reducing end of maize starch during retrogradation. The results of electrospray ionization-mass spectrometry [ESI-MS] show that the polypeptide (m/z 863) is present in all three hydrolysates remarkedly retarding maize starch retrogradation and its relative abundence is also the highest. So the polypeptide containing seven amino acids probably is the key component to significantly inhibit maize starch retrogradation. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Percutaneous radiologically guided gastrostomy tube placement: comparison of antegrade transoral and retrograde transabdominal approaches

    PubMed Central

    Haber, Zachary M.; Charles, Hearns W.; Gross, Jonathan S.; Pflager, Daniel; Deipolyi, Amy R.

    2017-01-01

    PURPOSE We aimed to compare the antegrade transoral and the retrograde transabdominal approaches for fluoroscopy-guided percutaneous gastrostomy tube (G-tube) placement. METHODS Following institutional review board approval, all G-tubes at two academic hospitals (January 2014 to May 2015) were reviewed retrospectively. Retrograde approach was used at Hospital 1 and both antegrade and retrograde approaches were used at Hospital 2. Chart review determined type of anesthesia used during placement, dose of radiation used, fluoroscopy time, procedure time, medical history, and complications. RESULTS A total of 149 patients (64 women, 85 men; mean age, 64.4±1.3 years) underwent G-tube placement, including 93 (62%) placed via the retrograde transabdominal approach and 56 (38%) placed via the antegrade transoral approach. Retrograde placement entailed fewer anesthesiology consultations (P < 0.001), less overall procedure time (P = 0.023), and less fluoroscopy time (P < 0.001). A comparison of approaches for placement within the same hospital demonstrated that the retrograde approach led to significantly reduced radiation dose (P = 0.022). There were no differences in minor complication rates (13%–19%; P = 0.430), or major complication rates (6%–7%; P = 0.871) between the two techniques. CONCLUSION G-tube placement using the retrograde transabdominal approach is associated with less fluoroscopy time, procedure time, radiation exposure, and need for anesthesiology consultation with similar safety profile compared with the antegrade transoral approach. Additionally, it is hypothesized that decreased procedure time and anesthesiology consultation using the transoral approach are likely associated with reduced cost. PMID:27911264

  16. Inhibition of gelatinized rice starch retrogradation by rice bran protein hydrolysates.

    PubMed

    Niu, Liya; Wu, Leiyan; Xiao, Jianhui

    2017-11-01

    The retrogradation of gelatinized rice starch (GRS) during the shelf life of a product is the biggest barrier related to starch-containing foods. The objective of this study was to produce rice bran protein hydrolysate (RBPH) using proteolytic enzymes (alcalase, flavourzyme, protamex, neutrase, bromelain, papain and trypsin) to suppress the retrogradation of GRS and understand the physical phenomena underlying the reduced retrogradation of GRS by RBPH during short- and long-term storage. Mixtures of GRS incorporated with Protamex-hydrolyzed rice bran protein at 1h (PRBPH-1) at a degree of hydrolysis of 15.1% were still fresh after storage at 4°C for 14 d. The dynamic time sweep results obtained at 4°C for 180min showed that PRBPH-1 reduced the storage modulus to a greater extent, indicating that PRBPH-1 suppressed the short-term retrogradation of GRS. Differential scanning calorimetry (DSC) clearly showed that PRBPH-1 significantly decreased the retrogradation enthalpy during the 28-d storage at 4°C, and the retrogradation kinetics were analyzed by the Avrami model. In addition, the recrystallization of GRS based on X-ray diffraction spectroscopy was reduced from 15.41% to 4.86% when the GRS: PRBPH-1mass ratio increased from 100:0 to 100:12. Confocal laser scanning microscopy, atomic force microscopy and scanning electron microscopy demonstrated that PRBPH-1 dispersed between GRS molecules to block the formation of hydrogen bonds to inhibit the recrystallization of GRS. These findings suggested that PRBPH-1 inhibited the short- and long-term retrogradation of GRS, and can be potently employed as a natural alternatives for improving the quality and nutrition of starch-containing foods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Endothelin-1 impairs retrograde axonal transport and leads to axonal injury in rat optic nerve.

    PubMed

    Taniguchi, Takazumi; Shimazawa, Masamitsu; Sasaoka, Masaaki; Shimazaki, Atsushi; Hara, Hideaki

    2006-05-01

    The purpose of this study was to examine the effects of endothelin-1 (ET-1) on retrograde axonal transport in the rat optic nerve. Vehicle or ET-1 (0.2, 1, or 5 pmol/eye) were injected into the vitreous body in Sprague-Dawley rats. Retinal vessels were observed, using a fundus camera, before, and at 10 min, 3 days and 7 days after a single intravitreous injection. Two days after the injection, a neuronal tracer, fluoro gold, was administered via the superior colliculi to retrogradely label active retinal ganglion cells (RGCs). Five days after the tracer administration, retrogradely labeled RGCs were evaluated in the flat-mounted retina, and cross sections from each optic nerve were graded for injury by four independent, masked observers. ET-1 at 5 pmol/eye caused a significant constriction of retinal vessels (versus the vehicle-treated group) at 10 min after the injection. Intravitreous injection of ET-1 caused a dose-related decrease in the number of retrogradely labeled RGCs. Injection of 5 pmol/eye ET-1 led to a statistically significant decrease in the number of retrogradely labeled RGCs (versus the vehicle-treated group). ET-1 at 1 and 5 pmol/eye caused histological optic nerve damage (evaluated using a graded scale). The histological optic nerve damage correlated with the number of retrogradely labeled RGCs. In conclusion, a single intravitreous injection of ET-1 impaired retrograde axonal transport in the rat optic nerve and this impairment correlated with the histological optic nerve damage.

  18. On remembering and forgetting our autobiographical pasts: retrograde amnesia and Andrew Mayes's contribution to neuropsychological method.

    PubMed

    Kopelman, M D; Bright, P

    2012-11-01

    Andrew Mayes's contribution to the neuropsychology of memory has consisted in steadily teasing out the nature of the memory deficit in the amnesic syndrome. This has been done with careful attention to matters of method at all stages. This particularly applies to his investigations of forgetting rates in amnesia and to his studies of retrograde amnesia. Following a brief outline of his work, the main current theories of retrograde amnesia are considered: consolidation theory, episodic-to-semantic shift theory, and multiple trace theory. Findings across the main studies in Alzheimer dementia are reviewed to illustrate what appears to be consistently found, and what is much more inconsistent. A number of problems and issues in current theories are then highlighted--including the nature of the temporal gradient, correlations with the extent of temporal lobe damage, what we would expect 'normal' remote memory curves to look like, how they would appear in focal retrograde amnesia, and whether we can pinpoint retrograde amnesia to hippocampal/medial temporal damage on the basis of existing studies. A recent study of retrograde amnesia is re-analysed to demonstrate temporal gradients on recollected episodic memories in hippocampal/medial temporal patients. It is concluded that there are two requirements for better understanding of the nature of retrograde amnesia: (i) a tighter, Mayesian attention to method in terms of both the neuropsychology and neuroimaging in investigations of retrograde amnesia; and (ii) acknowledging that there may be multiple factors underlying a temporal gradient, and that episodic and semantic memory show important interdependencies at both encoding and retrieval. Such factors may be critical to understanding what is remembered and what is forgotten from our autobiographical pasts. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Retrograde approach to an ostial left anterior descending chronic total occlusion through a left internal mammary artery graft.

    PubMed

    Hari, Pawan; Kirtane, Ajay J; Bangalore, Sripal

    2016-05-01

    Retrograde approach to chronic total occlusions (CTO) has been described via saphenous vein grafts, septal and epicardial collaterals. We report for the first time a successful retrograde approach to an ostial left anterior descending (LAD) artery CTO through a failed left internal mammary artery (LIMA) to LAD anastamosis. This case demonstrates the technical aspects of using a LIMA conduit as a retrograde approach to CTO. © 2015 Wiley Periodicals, Inc.

  20. The use of a cutting balloon in contemporary reverse controlled antegrade and retrograde subintimal tracking (reverse CART) technique.

    PubMed

    Nakabayashi, Keisuke; Okada, Hisayuki; Oka, Toshiaki

    2016-07-11

    The key concept of reverse controlled antegrade and retrograde tracking (CART) technique is retrograde puncture with a tapered wire to an antegrade balloon (contemporary reverse CART) or new connections between the antegrade and retrograde subintimal space (classical reverse CART). In our case, a 75-year-old man with severe chronic total occlusion of the right coronary artery, reverse CART with conventional balloons could not be accomplished. Externalization wiring was completed by contemporary reverse CART using a cutting balloon as an antegrade balloon to improve the fenestration force of the retrograde guidewire. Thus, the use of a cutting balloon for contemporary reverse CART might be promising.

  1. The retrogradation properties of glutinous rice and buckwheat starches as observed with FT-IR, 13C NMR and DSC.

    PubMed

    Lian, Xijun; Wang, Changjun; Zhang, Kunsheng; Li, Lin

    2014-03-01

    The experiment was conducted to study the retrogradation properties of glutinous rice and buckwheat starch with wavelengths of maximum absorbance, FT-IR, (13)C NMR, and DSC. The results show that the starches in retrograded glutinous rice starch and glutinous rice amylopectin could not form double helix. The IR results show that protein inhabits in glutinous rice and maize starches in a different way and appearance of C-H symmetric stretching vibration at 2852 cm(-1) in starch might be appearance of protein. Retrogradation untied the protein in glutinous amylopectin. Enthalpies of sweet potato and maize granules are higher than those of their retrograded starches. The (13)C NMR results show that retrogradation of those two starches leads to presence of β-anomers and retrogradation might decompose lipids in glutinous rice amylopectin into small molecules. Glutinous rice starch was more inclined to retrogradation than buckwheat starch. The DSC results show that the second peak temperatures for retrograded glutinous rice and buckwheat starches should be assigned to protein. The SEM results show that an obvious layer structure exists in retrograded glutinous rice amylopectin.

  2. Retrograde ejaculation after anterior lumbar interbody fusion: transperitoneal versus retroperitoneal exposure.

    PubMed

    Sasso, Rick C; Kenneth Burkus, J; LeHuec, Jean-Charles

    2003-05-15

    In this multicenter, prospective, 2-year study, 146 male patients underwent a single-level anterior lumbar interbody fusion with a tapered threaded titanium fusion device. All the patients were advised before surgery of the risk for retrograde ejaculation. After surgery, any case of retrograde ejaculation was recorded as an adverse event, and the patient was observed up for the remainder of the study. To determine the incidence of retrograde ejaculation in male patients treated for single-level degenerative lumbar disc disease at L4-L5 or L5-S1 with a stand-alone anterior interbody fusion using tapered, threaded titanium fusion cages. The incidence of retrograde ejaculation in men after anterior lumbosacral spinal surgery has been reported to range from 0.42% to 5.9%. Various risk factors that increase the chance of retrograde ejaculation have been proposed. In this prospective study, 146 male patients underwent an open surgical exposure of the lumbosacral junction and a single-level interbody fusion at either L4-L5 or L5-S1. Assessment of a patient's clinical outcome was based on written questionnaires at 6 weeks and then 3, 6, 12, and 24 months after surgery. Patients were questioned about adverse events at each of these assessments, and any case of retrograde ejaculation was recorded and followed. Retrograde ejaculation developed in 6 of the 146 men after open anterior lumbar interbody fusion surgery. Two cases (1.7%; 2/116) involved patients who underwent a retroperitoneal surgical exposure. Four cases (13.3%; 4/30) involved patients who had a transperitoneal surgical exposure. This difference is statistically significant according to Fisher's exact test (P = 0.017). At 12 months after surgery, 2 patients had resolution of their symptoms: 1 in the retroperitoneal approach group and 1 in the transperitoneal group. At the final 2-year follow-up, no changes in symptoms were reported. One patient in the retroperitoneal approach group (0.86%) and three patients in

  3. Hypothermic perfusion with retrograde outflow during right hepatectomy is safe and feasible.

    PubMed

    Reiniers, Megan J; Olthof, Pim B; van Golen, Rowan F; Heger, Michal; van Beek, Adriaan A; Meijer, Ben; Leen, René; van Kuilenburg, André B P; Mearadji, Banafsche; Bennink, Roelof J; Verheij, Joanne; van Gulik, Thomas M

    2017-07-01

    In situ hypothermic perfusion during liver resection performed under vascular inflow occlusion decreases hepatic ischemia-reperfusion injury, but technical limitations have restricted its widespread use. In situ hypothermic perfusion with retrograde outflow circumvents these impediments and thus could extend the applicability of in situ hypothermic perfusion. The safety and feasibility of in situ hypothermic perfusion with retrograde outflow were analyzed in selected patients undergoing right (extended) hepatectomy and compared to intermittent vascular inflow occlusion, the gold standard method, in this randomized pilot study. Patients were first screened for parenchymal liver disease (exclusion criteria: steatosis ≥30%, cirrhosis, or cholestasis). Study participants were randomized intraoperatively to undergo in situ hypothermic perfusion with retrograde outflow (n = 9) or intermittent vascular inflow occlusion (n = 9). The target liver core temperature during in situ hypothermic perfusion with retrograde outflow was 28°C. The primary end point was ischemia-reperfusion injury (expressed by peak postoperative transaminase levels). Secondary outcomes included functional liver regeneration (assessed by hepatobiliary scintigraphy) and clinical outcomes. Peak transaminase levels, total bilirubin, and the international normalized ratio were similar between both groups, although a trend toward more rapid normalization of bilirubin levels was noted for the in situ hypothermic perfusion with retrograde outflow group. Functional liver regeneration as evaluated by hepatobiliary scintigraphy was improved on postoperative day 3 fafter in situ hypothermic perfusion with retrograde outflow but not after intermittent vascular inflow occlusion. Furthermore, in situ hypothermic perfusion with retrograde outflow (requiring continuous ischemia) was comparable to intermittent vascular inflow occlusion for all clinical outcomes, including postoperative complications and hospital

  4. Retrogradation of Maize Starch after High Hydrostatic Pressure Gelation: Effect of Amylose Content and Depressurization Rate

    PubMed Central

    Yang, Zhi; Swedlund, Peter; Gu, Qinfen; Hemar, Yacine; Chaieb, Sahraoui

    2016-01-01

    High hydrostatic pressure (HHP) has been employed to gelatinize or physically modify starch dispersions. In this study, waxy maize starch, normal maize starch, and two high amylose content starch were processed by a HHP of the order of 600 MPa, at 25°C for 15min. The effect of HHP processing on the crystallization of maize starches with various amylose content during storage at 4°C was investigated. Crystallization kinetics of HHP treated starch gels were investigated using rheology and FTIR. The effect of crystallization on the mechanical properties of starch gel network were evaluated in terms of dynamic complex modulus (G*). The crystallization induced increase of short-range helices structures were investigated using FTIR. The pressure releasing rate does not affect the starch retrogradation behaviour. The rate and extent of retrogradation depends on the amylose content of amylose starch. The least retrogradation was observed in HHP treated waxy maize starch. The rate of retrogradation is higher for HHP treated high amylose maize starch than that of normal maize starch. A linear relationship between the extent of retrogradation (phase distribution) measured by FTIR and G* is proposed. PMID:27219066

  5. Exercise intensity modulates brachial artery retrograde blood flow and shear rate during leg cycling in hypoxia

    PubMed Central

    Iwamoto, Erika; Katayama, Keisho; Ishida, Koji

    2015-01-01

    The purpose of this study was to elucidate the effect of exercise intensity on retrograde blood flow and shear rate (SR) in an inactive limb during exercise under normoxic and hypoxic conditions. The subjects performed two maximal exercise tests on a semi-recumbent cycle ergometer to estimate peak oxygen uptake (O2peak) while breathing normoxic (inspired oxygen fraction [FIO2 = 0.21]) and hypoxic (FIO2 = 0.12 or 0.13) gas mixtures. Subjects then performed four exercise bouts at the same relative intensities (30 and 60% O2peak) for 30 min under normoxic or hypoxic conditions. Brachial artery diameter and blood velocity were simultaneously recorded, using Doppler ultrasonography. Retrograde SR was enhanced with increasing exercise intensity under both conditions at 10 min of exercise. Thereafter, retrograde blood flow and SR in normoxia returned to pre-exercise levels, with no significant differences between the two exercise intensities. In contrast, retrograde blood flow and SR in hypoxia remained significantly elevated above baseline and was significantly greater at 60% than at 30% O2peak. We conclude that differences in exercise intensity affect brachial artery retrograde blood flow and SR during prolonged exercise under hypoxic conditions. PMID:26038470

  6. Exercise intensity modulates brachial artery retrograde blood flow and shear rate during leg cycling in hypoxia.

    PubMed

    Iwamoto, Erika; Katayama, Keisho; Ishida, Koji

    2015-06-01

    The purpose of this study was to elucidate the effect of exercise intensity on retrograde blood flow and shear rate (SR) in an inactive limb during exercise under normoxic and hypoxic conditions. The subjects performed two maximal exercise tests on a semi-recumbent cycle ergometer to estimate peak oxygen uptake (V˙O2peak) while breathing normoxic (inspired oxygen fraction [FIO2 = 0.21]) and hypoxic (FIO2 = 0.12 or 0.13) gas mixtures. Subjects then performed four exercise bouts at the same relative intensities (30 and 60% V˙O2peak) for 30 min under normoxic or hypoxic conditions. Brachial artery diameter and blood velocity were simultaneously recorded, using Doppler ultrasonography. Retrograde SR was enhanced with increasing exercise intensity under both conditions at 10 min of exercise. Thereafter, retrograde blood flow and SR in normoxia returned to pre-exercise levels, with no significant differences between the two exercise intensities. In contrast, retrograde blood flow and SR in hypoxia remained significantly elevated above baseline and was significantly greater at 60% than at 30% V˙O2peak. We conclude that differences in exercise intensity affect brachial artery retrograde blood flow and SR during prolonged exercise under hypoxic conditions. © 2015 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.

  7. Effect of storage time on the retrogradation of banana starch extrudate.

    PubMed

    Bello-Pérez, L A; Ottenhof, M-A; Agama-Acevedo, E; Farhat, I A

    2005-02-23

    Starch was isolated from banana starch and the retrogradation phenomenon was studied using diverse techniques, including an enzymatic measurement. Wide-angle X-ray scattering (WAXS) showed that the sample stored for 7 h presented small peaks and when the storage time increased the peaks increased in intensity. The type of diffraction pattern found in banana extrudates is typical of the A-type crystal polymorph. The crystallinity index from the diffractograms, showed a plateau after approximately 20 h of storage. The short-range order measurement with Fourier transform infrared (FTIR) spectroscopy showed that banana starch retrogradation reached a maximum value at approximately 11 h of storage, a value that agrees with the results obtained with differential scanning calorimetry (DSC), because the maximum enthalpy value (approximately 5 J/g) was calculated in the stored sample for 8 h, without changes in the stored samples for more time. Retrograded resistant starch values did not change after 12 h of storage, obtaining the maximum starch retrogradation level. FTIR, DSC, and the enzymatic technique showed the changes at the molecular level in starch during storage; in the case of WAXS, they determine the long-range order that explains the differences found in the starch retrogradation pattern measurement in banana starch.

  8. Profound loss of general knowledge in retrograde amnesia: evidence from an amnesic artist.

    PubMed

    Gregory, Emma; McCloskey, Michael; Landau, Barbara

    2014-01-01

    Studies of retrograde amnesia have focused on autobiographical memory, with fewer studies examining how non-autobiographical memory is affected. Those that have done so have focused primarily on memory for famous people and public events-relatively limited aspects of memory that are tied to learning during specific times of life and do not deeply tap into the rich and extensive knowledge structures that are developed over a lifetime. To assess whether retrograde amnesia can also cause impairments to other forms of general world knowledge, we explored losses across a broad range of knowledge domains in a newly-identified amnesic. LSJ is a professional artist, amateur musician and history buff with extensive bilateral medial temporal and left anterior temporal damage. We examined LSJ's knowledge across a range of everyday domains (e.g., sports) and domains for which she had premorbid expertise (e.g., famous paintings). Across all domains tested, LSJ showed losses of knowledge at a level of breadth and depth never before documented in retrograde amnesia. These results show that retrograde amnesia can involve broad and deep deficits across a range of general world knowledge domains. Thus, losses that have already been well-documented (famous people and public events) may severely underestimate the nature of human knowledge impairment that can occur in retrograde amnesia.

  9. The effect of partial gelatinization of corn starch on its retrogradation.

    PubMed

    Fu, Zong-qiang; Wang, Li-jun; Li, Dong; Zhou, Yu-guang; Adhikari, Benu

    2013-09-12

    The objective of this work was to investigate the effect of partial gelatinization of starch on its retrogradation using differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques. The Avrami equation was used to predict the evolution of starch retrogradation kinetics. The degree of retrogradation in starch samples partially gelatinized 64°C (S64), 68°C (S68) and 70°C (S70) and control (S25) increased with storage time. The retrogradation enthalpies of S68 and S70 were almost four times as high as that of S64. The S25 and S64 had dominant A-type crystalline pattern while S68 and S70 showed dominant B-type crystalline pattern. The growth of remainder crystals was faster in S25 and S64, while both the nucleation and growth rates of new crystals were faster in S68 and S70. The Avrami model was found to represent the retrogradation kinetics data of these partially gelatinized starch samples quite satisfactorily (R(2)>0.95). Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Mechanisms influencing retrograde flow in the atrioventricular canal during early embryonic cardiogenesis.

    PubMed

    Bulk, Alexander; Bark, David; Johnson, Brennan; Garrity, Deborah; Dasi, Lakshmi Prasad

    2016-10-03

    Normal development of the heart is regulated, in part, by mechanical influences associated with blood flow during early stages of embryogenesis. Specifically, the potential for retrograde flow at the atrioventricular canal (AVC) is particularly important in valve development. However, the mechanisms causing this retrograde flow have received little attention. In this study, a numerical analysis was performed on images of the embryonic zebrafish heart between 48 and 55hpf. During these stages, normal retrograde flow is prevalent. To manipulate this flow, zebrafish were placed in a centrifuge and subjected to a hypergravity environment to alter the cardiac preload at various six-hour intervals between 24 and 48hpf. Parameters of the pumping mechanics were then analyzed through a spatiotemporal analysis of processed image sequences. We find that the loss of retrograde flow in experimentally manipulated embryos occurs in part because of a greater resistance in the form of atrial and AVC contractile closure. Additionally, during retrograde flow, these embryos exhibit significantly greater pressure difference across the AVC based on calculations of expansive and contractile rates of the atrium and ventricle. These results elucidated that the developing heart is highly sensitive to small changes in pumping mechanics as it strives to maintain normal hemodynamic conditions necessary for later cardiac development.

  11. Preparation of chitosan oligomers COS and their effect on the retrogradation of intermediate amylose rice starch.

    PubMed

    Wu, Yue; Lin, Qin Lu; Chen, Zheng Xing; Wu, Wei; Xiao, Hua Xi

    2012-12-01

    Chitosan oligomers (COS) were obtained by enzymatic hydrolysis and H2O2 oxidative treatment, and then separated into different fractions using ultra-filtration membranes. Each COSM fraction prepared using enzymatic hydrolysis retained its structure, especially the reduced end residue (-NH2 group), and had a peak for molecular weight. On the other hand, each COSH fraction prepared by oxidative treatment had partly damaged -NH2 groups and two peaks for molecular weight. These results indicate that the same COS fractions prepared by the two methods differ in their amino groups and in their molecular weights, though they can both pass through the same size ultra-filtration membrane. The effect of COS on the retrogradation of intermediate amylose rice starch (IA-RS) was also investigated. The 5 k < COSM < 10 k fraction had the best anti-retrogradation ability; the retrogradation ratio of IA-RS with this fraction was reduced by 14.5%, compared to the control, and its relative crystallinity was only 59.69%. 10 k < COSM < 30 k fraction was second best, while the COSM < 5 k fraction had no effect. Therefore, the molecular size of COS determined its anti-retrogradation capability. All COSH fractions from oxidative treatment had no effect on the retrogradation.

  12. Characterization of the primary spinal afferent innervation of the mouse colon using retrograde labelling.

    PubMed

    Robinson, D R; McNaughton, P A; Evans, M L; Hicks, G A

    2004-02-01

    Visceral pain is the most common form of pain produced by disease and is thus of interest in the study of gastrointestinal (GI) complaints such as irritable bowel syndrome, in which sensory signals perceived as GI pain travel in extrinsic afferent neurones with cell bodies in the dorsal root ganglia (DRG). The DRG from which the primary spinal afferent innervation of the mouse descending colon arises are not well defined. This study has combined retrograde labelling and immunohistochemistry to identify and characterize these neurones. Small to medium-sized retrogradely labelled cell bodies were found in the DRG at levels T8-L1 and L6-S1. Calcitonin gene-related peptide (CGRP)- and P2X3-like immunoreactivity (LI) was seen in 81 and 32%, respectively, of retrogradely labelled cells, and 20% bound the Griffonia simplicifolia-derived isolectin IB4. CGRP-LI and IB4 were co-localized in 22% of retrogradely labelled cells, whilst P2X3-LI and IB4 were co-localized in 7% (vs 34% seen in the whole DRG population). Eighty-two per cent of retrogradely labelled cells exhibited vanilloid receptor 1-like immunoreactivity (VR1-LI). These data suggest that mouse colonic spinal primary afferent neurones are mostly peptidergic CGRP-containing, VR1-LI, C fibre afferents. In contrast to the general DRG population, a subset of neurones exist that are P2X3 receptor-LI but do not bind IB4.

  13. Retrograde versus Antegrade Approach for the Management of Large Proximal Ureteral Stones

    PubMed Central

    Mykoniatis, Ioannis; Isid, Ayman; Gofrit, Ofer N.; Rosenberg, Shilo; Hidas, Guy; Landau, Ezekiel H.; Pode, Dov; Duvdevani, Mordechai

    2016-01-01

    Objective. To evaluate and compare the efficacy and safety of retrograde versus antegrade ureteroscopic lithotripsy for the treatment of large proximal ureteral stones. Patients and Methods. We retrospectively analyzed the medical records of patients with proximal ureteral stones >15 mm, treated in our institution from January 2011 to January 2016. Intraoperative parameters, postoperative outcomes, and complications were recorded and compared between the two techniques. Results. Our analysis included 57 patients. Thirty-four patients (59.6%) underwent retrograde and 23 patients (40.4%) underwent antegrade ureteroscopy. There was no significant difference in patients' demographics and stone characteristics between the groups. Stone-free rate was significantly higher (p = 0.033) in the antegrade group (100%) compared to retrograde one (82.4%). Fluoroscopy time, procedure duration, and length of hospitalization were significantly (p < 0.001) lower in retrograde approach. On the other hand, the need for postoperative stenting was significantly lower in the antegrade group (p < 0.001). No difference was found between the groups (p = 0.745) regarding postoperative complications. Conclusions. Antegrade ureteroscopy is an efficient and safe option for the management of large proximal ureteral stones. It may achieve high stone-free rates compared to retrograde ureteroscopy with the drawback of longer operative time, fluoroscopy time, and length of hospitalization. PMID:27766263

  14. Profound loss of general knowledge in retrograde amnesia: evidence from an amnesic artist

    PubMed Central

    Gregory, Emma; McCloskey, Michael; Landau, Barbara

    2014-01-01

    Studies of retrograde amnesia have focused on autobiographical memory, with fewer studies examining how non-autobiographical memory is affected. Those that have done so have focused primarily on memory for famous people and public events—relatively limited aspects of memory that are tied to learning during specific times of life and do not deeply tap into the rich and extensive knowledge structures that are developed over a lifetime. To assess whether retrograde amnesia can also cause impairments to other forms of general world knowledge, we explored losses across a broad range of knowledge domains in a newly-identified amnesic. LSJ is a professional artist, amateur musician and history buff with extensive bilateral medial temporal and left anterior temporal damage. We examined LSJ's knowledge across a range of everyday domains (e.g., sports) and domains for which she had premorbid expertise (e.g., famous paintings). Across all domains tested, LSJ showed losses of knowledge at a level of breadth and depth never before documented in retrograde amnesia. These results show that retrograde amnesia can involve broad and deep deficits across a range of general world knowledge domains. Thus, losses that have already been well-documented (famous people and public events) may severely underestimate the nature of human knowledge impairment that can occur in retrograde amnesia. PMID:24834048

  15. Retrogradation of Maize Starch after High Hydrostatic Pressure Gelation: Effect of Amylose Content and Depressurization Rate.

    PubMed

    Yang, Zhi; Swedlund, Peter; Gu, Qinfen; Hemar, Yacine; Chaieb, Sahraoui

    2016-01-01

    High hydrostatic pressure (HHP) has been employed to gelatinize or physically modify starch dispersions. In this study, waxy maize starch, normal maize starch, and two high amylose content starch were processed by a HHP of the order of 600 MPa, at 25°C for 15min. The effect of HHP processing on the crystallization of maize starches with various amylose content during storage at 4°C was investigated. Crystallization kinetics of HHP treated starch gels were investigated using rheology and FTIR. The effect of crystallization on the mechanical properties of starch gel network were evaluated in terms of dynamic complex modulus (G*). The crystallization induced increase of short-range helices structures were investigated using FTIR. The pressure releasing rate does not affect the starch retrogradation behaviour. The rate and extent of retrogradation depends on the amylose content of amylose starch. The least retrogradation was observed in HHP treated waxy maize starch. The rate of retrogradation is higher for HHP treated high amylose maize starch than that of normal maize starch. A linear relationship between the extent of retrogradation (phase distribution) measured by FTIR and G* is proposed.

  16. Clinical efficacy of intermittent pressure augmented-retrograde cerebral perfusion.

    PubMed

    Endo, Hidehito; Kubota, Hiroshi; Tsuchiya, Hiroshi; Yoshimoto, Akihiro; Takahashi, Yu; Inaba, Yusuke; Sudo, Kenichi

    2013-03-01

    During aortic surgery under hypothermic circulatory arrest, retrograde cerebral perfusion (RCP) is commonly used as a cerebroprotective method to extend the duration of circulatory arrest safely. Kitahori and colleagues described a novel protocol of RCP using intermittent pressure augmented (IPA)-RCP in 2005. The aim of the present study was to determine the clinical effectiveness of this novel protocol. A total of 20 consecutive patients undergoing total replacement of the aortic arch were assigned to a conventional RCP (n = 10) or an IPA-RCP group (n = 10). Cerebral perfusion was provided at a continuous venous pressure of 25 mm Hg in the conventional RCP, and venous pressure was intermittently provided at 20 mm Hg for 120 seconds and at 45 mm Hg for 30 seconds in the IPA-RCP group. The clinical outcomes were compared between the 2 groups. Regional cerebral oxygen saturation (rSO(2)) was measured using near infrared spectroscopy every 10 minutes from the beginning of RCP initiation. To represent the brain oxygen consumption, the decline ratio of rSO(2) was calculated. There was no surgical mortality or major neurologic complications in either group. The interval from the end of surgery to full wakefulness was significantly shorter in the IPA-RCP group (85 ± 64 minutes) than in the conventional RCP group (310 ± 282 minutes; P < .05). Although the initial rSO(2) value did not show significant difference in both groups, the rSO(2) with IPA-RCP was greater than that with conventional RCP from 10 to 70 minutes (P < .05). The decline ratio of rSO(2) was lower in the IPA-RCP group than in the RCP perfusion group at all points (P < .05). IPA-RCP might provide more homogenous cerebral perfusion and a more effective oxygen supply to the brain with better clinical results than conventional RCP. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  17. Pharmacological prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis.

    PubMed

    Pande, Hemant; Thuluvath, Paul

    2003-01-01

    The incidence of clinically significant pancreatitis after endoscopic retrograde cholangiopancreatography (ERCP) ranges from 1-13.5%. It is more common after therapeutic procedures such as sphincterotomy or balloon dilatation of the sphincter, and diagnostic procedures such as biliary or pancreatic manometry. The severity of post-ERCP pancreatitis may vary from very mild to extremely severe disease with multiple organ failure and fatal outcome. Several factors including papillary oedema, injection of hyperosmolar contrast-material, introduction of previously activated enzymes during repeated cannulation, bacterial contamination and thermal injury from endoscopic sphincterotomy have been implicated as triggering factors that initiate the sequential cascade of pancreatic autodigestion and release of proinflammatory cytokines leading to acute pancreatitis. Recovery from post-ERCP pancreatitis is usually rapid when the injury is confined to the pancreas. However, systemic production of inflammatory mediators may lead to the development of more serious manifestations including multiorgan failure.A wide range of pharmacological agents has been tested in experimental and clinical trials, but the results have been largely disappointing. Several drugs are discussed in this review, but only somatostatin and gabexate (gabexate mesilate) have consistently shown a moderate beneficial effect. In clinical trials, both gabexate and somatostatin appear equally effective in reducing the incidence of pancreatitis by two-thirds compared with controls. However, both drugs need to be given by continuous infusion for about 12 hours and this makes them less cost-effective than conventional treatment. One potential strategy is to reserve these drugs for high-risk patients undergoing ERCP. Preliminary studies have shown encouraging results with nitroglycerin, antibacterials and heparin. However, these observations need to be corroborated in a rigorous fashion in large, randomised, double

  18. Retrograde binaries of massive black holes in circumbinary accretion discs

    NASA Astrophysics Data System (ADS)

    Amaro-Seoane, Pau; Maureira-Fredes, Cristián; Dotti, Massimo; Colpi, Monica

    2016-06-01

    accretion only explores the late evolution stages of the binary in an otherwise unperturbed retrograde disc to illustrate how eccentricity evolves with time in relation to the shape of the underlying surface density distribution.

  19. GBT Reveals Satellite of Milky Way in Retrograde Orbit

    NASA Astrophysics Data System (ADS)

    2003-05-01

    New observations with National Science Foundation's Robert C. Byrd Green Bank Telescope (GBT) suggest that what was once believed to be an intergalactic cloud of unknown distance and significance, is actually a previously unrecognized satellite galaxy of the Milky Way orbiting backward around the Galactic center. Path of Complex H Artist's rendition of the path of satellite galaxy Complex H (in red) in relation to the orbit of the Sun (in yellow) about the center of the Milky Way Galaxy. The outer layers of Complex H are being stripped away by its interaction with the Milky Way. The hydrogen atmosphere (in blue) is shown surrounding the visible portion (in white) of the Galaxy. CREDIT: Lockman, Smiley, Saxton; NRAO/AUI Jay Lockman of the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia, discovered that this object, known as "Complex H," is crashing through the outermost parts of the Milky Way from an inclined, retrograde orbit. Lockman's findings will be published in the July 1 issue of the Astrophysical Journal, Letters. "Many astronomers assumed that Complex H was probably a distant neighbor of the Milky Way with some unusual velocity that defied explanation," said Lockman. "Since its motion appeared completely unrelated to Galactic rotation, astronomers simply lumped it in with other high velocity clouds that had strange and unpredictable trajectories." High velocity clouds are essentially what their name implies, fast-moving clouds of predominately neutral atomic hydrogen. They are often found at great distances from the disk of the Milky Way, and may be left over material from the formation of our Galaxy and other galaxies in our Local Group. Over time, these objects can become incorporated into larger galaxies, just as small asteroids left over from the formation of the solar system sometimes collide with the Earth. Earlier studies of Complex H were hindered because the cloud currently is passing almost exactly behind the outer disk of

  20. Failure of conventional retrograde cystography to detect bladder ruptures in pelvic trauma.

    PubMed

    Berber, O; Emeagi, C; Perry, M; Rickman, M S

    2011-03-01

    Conventional retrograde cystography is often used to investigate patients with suspected bladder ruptures in pelvic trauma. Clinical indicators suggestive of a rupture include haematuria and suprapubic tenderness and should increase the suspicion of bladder and urinary tract injury and prompt the clinician to undertake further investigations. Two patients with high-energy pelvic fractures had bladder ruptures detected intraoperatively despite normal preoperative retrograde cystogram. Both patients had significant clinical indicators suggestive of underlying bladder and urinary tract injury. In both cases, a routine conventional retrograde cystogram was performed but failed to identify the full extent of the bladder injury. A possible reason for misdiagnosis in these cases is the delay between injury and investigation due to tertiary referral of care.

  1. [Shock wave lithotripsy, retrograde intrarenal surgery or percutaneous nephrolithotomy for lower pole renal stones?].

    PubMed

    Rojas, Alejandro; Gallegos, Héctor; Salvadó, José A

    2015-09-09

    Among the therapeutic alternatives available for the treatment of lower pole renal calculi are extracorporeal lithotripsy, percutaneous nephrolithotomy and retrograde intrarenal surgery. There is controversy about which of these techniques is more effective, especially for stones smaller than 20 mm. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified four systematic reviews including 11 pertinent randomized controlled trials overall. We combined the evidence and generated a summary of findings following the GRADE approach. We concluded percutaneous nephrolithotomy probably increases success rate, but it is not clear if it decreases the need of retreatment compared to extracorporeal shock wave lithotripsy. In comparison to retrograde intrarenal surgery, it may increase success rate, but it is not clear if it decreases the need of retreatment. Retrograde intrarenal surgery may increase success rate, and probably decreases need of retreatment compared to extracorporeal shock wave lithotripsy.

  2. The effects of electrolysis at room temperature on retrogradation of sweet potato starch.

    PubMed

    Xijun, Lian; Kunsheng, Zhang; Qingfeng, Luo; Xu, Zhang; Shuyi, Zhao

    2012-01-01

    The effects of electrolysis at room temperature on formation of sweet potato retrograded starch were studied by photographic method in the paper. The optimal parameters of electrolytic preparation of sweet potato retrograded starch were determined. The ratio between sweet potato starch and water was 10 g/100 mL with addition of NaCl 1.0 g/100 mL, pH value of the solution was 6.0 and the solution was electrolyzed for 30 min at 90 V at room temperature, then it was stored at 4°C for 24h after being autoclaved for 30 min at 120°C, the retrogradation rate of sweet potato starch at this condition was 33.1%, which is 138% higher than that of control group. Four possible reasons are put forward to explain the results. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

  3. Transport According to GARP: Receiving Retrograde Cargo at the Trans-Golgi Network

    PubMed Central

    Bonifacino, Juan S.; Hierro, Aitor

    2010-01-01

    Tethering factors are large protein complexes that capture transport vesicles and enable their fusion with acceptor organelles at different stages of the endomembrane system. Recent studies have shed new light on the structure and function of a heterotetrameric tethering factor named Golgi-associated retrograde protein (GARP), which promotes fusion of endosome-derived, retrograde transport carriers to the trans-Golgi network (TGN). X-ray crystallography of the Vps53 and Vps54 subunits of GARP has revealed that this complex is structurally related to other tethering factors such as the exocyst, COG and Dsl1, indicating that they all might work by a similar mechanism. Loss of GARP function compromises the growth, fertility and/or viability of the defective organisms, underscoring the essential nature of GARP-mediated retrograde transport. PMID:21183348

  4. Selective retrograde labeling of cholinergic neurons with (/sup 3/H)choline

    SciTech Connect

    Bagnoli, P.; Beaudet, A.; Stella, M.; Cuenod, M.

    1981-07-01

    Evidence is presented which is consistent with a specific retrograde labeling of cholinergic neurons following (/sup 3/H)choline application in their zone of termination. (/sup 3/H)Choline injection in the rat hippocampus leads to perikaryal retrograde labeling in the ipsilateral medial septal nuclease and nucleus of the diagonal band, thus delineating an established cholinergic pathway, while only diffuse presumably anterograde labeling was observed in the lateral septum, the entorhinal cortex, and the opposite hippocampus. After (/sup 3/H)choline injection in the pigeon visual Wulst, only the ipsilateral thalamic relay, of all inputs, showed similar perikaryal retrograde labeling, an observation supporting the suggestion that at least some thalamo-Wulst neurons are cholinergic.

  5. Retrograde semaphorin signaling regulates synapse elimination in the developing mouse brain.

    PubMed

    Uesaka, Naofumi; Uchigashima, Motokazu; Mikuni, Takayasu; Nakazawa, Takanobu; Nakao, Harumi; Hirai, Hirokazu; Aiba, Atsu; Watanabe, Masahiko; Kano, Masanobu

    2014-05-30

    Neural circuits are shaped by elimination of early-formed redundant synapses during postnatal development. Retrograde signaling from postsynaptic cells regulates synapse elimination. In this work, we identified semaphorins, a family of versatile cell recognition molecules, as retrograde signals for elimination of redundant climbing fiber to Purkinje cell synapses in developing mouse cerebellum. Knockdown of Sema3A, a secreted semaphorin, in Purkinje cells or its receptor in climbing fibers accelerated synapse elimination during postnatal day 8 (P8) to P18. Conversely, knockdown of Sema7A, a membrane-anchored semaphorin, in Purkinje cells or either of its two receptors in climbing fibers impaired synapse elimination after P15. The effect of Sema7A involves signaling by metabotropic glutamate receptor 1, a canonical pathway for climbing fiber synapse elimination. These findings define how semaphorins retrogradely regulate multiple processes of synapse elimination. Copyright © 2014, American Association for the Advancement of Science.

  6. Effect of high-speed jet on flow behavior, retrogradation, and molecular weight of rice starch.

    PubMed

    Fu, Zhen; Luo, Shun-Jing; BeMiller, James N; Liu, Wei; Liu, Cheng-Mei

    2015-11-20

    Effects of high-speed jet (HSJ) treatment on flow behavior, retrogradation, and degradation of the molecular structure of indica rice starch were investigated. Decreasing with the number of HSJ treatment passes were the turbidity of pastes (degree of retrogradation), the enthalpy of melting of retrograded rice starch, weight-average molecular weights and weight-average root-mean square radii of gyration of the starch polysaccharides, and the amylopectin peak areas of SEC profiles. The areas of lower-molecular-weight polymers increased. The chain-length distribution was not significantly changed. Pastes of all starch samples exhibited pseudoplastic, shear-thinning behavior. HSJ treatment increased the flow behavior index and decreased the consistency coefficient and viscosity. The data suggested that degradation of amylopectin was mainly involved and that breakdown preferentially occurred in chains between clusters.

  7. Transport according to GARP: receiving retrograde cargo at the trans-Golgi network.

    PubMed

    Bonifacino, Juan S; Hierro, Aitor

    2011-03-01

    Tethering factors are large protein complexes that capture transport vesicles and enable their fusion with acceptor organelles at different stages of the endomembrane system. Recent studies have shed new light on the structure and function of a heterotetrameric tethering factor named Golgi-associated retrograde protein (GARP), which promotes fusion of endosome-derived, retrograde transport carriers to the trans-Golgi network (TGN). X-ray crystallography of the Vps53 and Vps54 subunits of GARP has revealed that this complex is structurally related to other tethering factors such as the exocyst, the conserved oligomeric Golgi (COG) and Dsl1 (dependence on SLY1-20) complexes, indicating that they all might work by a similar mechanism. Loss of GARP function compromises the growth, fertility and/or viability of the defective organisms, emphasizing the essential nature of GARP-mediated retrograde transport.

  8. Subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) and rertograde access for critical limb ischemia.

    PubMed

    Hendricks, Nicholas J; Sabri, Saher S

    2014-09-01

    Retrograde access techniques involve the addition of a retrograde access into the distal target vessel to aid in recanalization of chronic total occlusions. Many patients with critical limb ischemia are also poor surgical candidates because of comorbidities or lack of suitable landing zone for bypass procedures. This approach may be helpful in the setting of chronic occlusions that cannot be crossed via conventional antegrade true-lumen approaches. Subintimal arterial flossing with antegrade-retrograde intervention technique can be used when the occlusion was crossed in the subintimal plane and antegrade re-entry techniques failed. It may also be useful for flush superficial femoral artery occlusions or those lesions that extend into the trifurcation vessels. Proficiency in these techniques allows limb salvage in patients who lack surgical options and would otherwise undergo amputation.

  9. The outcome of intracytoplasmic sperm injection in patients with retrograde ejaculation.

    PubMed

    Nikolettos, N; Al-Hasani, S; Baukloh, V; Schöpper, B; Demirel, L C; Baban, N; Sturm, R; Rudolf, K; Tomalak, K; Tinneberg, H R; Diedrich, K

    1999-09-01

    The objective of this retrospective clinical study was to assess the benefit of assisted fertilization in cases of anejaculatory infertility due to retrograde ejaculation. We report the outcome of intracytoplasmic sperm injection (ICSI) treatment. In 16 couples in which the men suffered from retrograde ejaculation. We performed 35 cycles of ICSI with spermatozoa retrieved from post-ejaculatory urine. The patients had been instructed to alkalinize the urine by ingesting sodium bicarbonate before the procedure. The fertilization rate averaged 51.2%. Seven clinical pregnancies were achieved. Three spontaneous first trimester abortions occurred, but three live offspring were delivered and one pregnancy is ongoing. In conclusion, the use of ICSI may be feasible for patients with retrograde ejaculation who are resistant to medical treatment and whose sperm quality is so low or unpredictable that intrauterine insemination or conventional methods of in-vitro fertilization are not possible.

  10. Healthy live birth using theophylline in a case of retrograde ejaculation and absolute asthenozoospermia.

    PubMed

    Ebner, Thomas; Shebl, Omar; Mayer, Richard Bernhard; Moser, Marianne; Costamoling, Walter; Oppelt, Peter

    2014-02-01

    To analyze whether the use of ready-to-use theophylline is a feasible option in a case of retrograde ejaculation and absolute asthenozoospermia. Case report. In vitro fertilization unit of a public hospital. Thirty-one-year-old nulliparous woman, and 39-year-old male with retrograde ejaculation and absolute asthenozoospermia. Retrieval of postejaculatory urine, restoration of motility using a methylxanthine, intracytoplasmic sperm injection, single-embryo transfer. Sperm motility, fertilization, embryo quality, live birth. Successful fertilization and a single-embryo transfer resulted in a healthy live birth. Theophylline turned out to be a safe, efficient agent for stimulating immotile spermatozoa in patients with retrograde ejaculation. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  11. Retrograde Ejaculation: A Rare Presenting Symptom of Type 1 Diabetes Mellitus.

    PubMed

    Kam, Jonathan; Tsang, Venessa H; Chalasani, Venu

    2017-01-01

    A 19 year old presented with a progressive decline in ejaculate volume over 2 weeks, followed by a complete absence of ejaculate emission. A post-ejaculatory urine specimen demonstrated spermatozoa confirming a diagnosis of retrograde ejaculation. Investigations revealed a raised blood glucose level of 24.5 mmol/L and HbA1c >15%, with positive tests for anti-GAD antibodies and anti-IA2 antibodies consistent with a diagnosis of Type 1 diabetes mellitus. Retrograde ejaculation in diabetes is associated with autonomic neuropathy and is a late feature of the disease. This case is unique with retrograde ejaculation being the primary presenting symptom of Type 1 diabetes mellitus.

  12. Fundamental studies of retrograde reactions in direct liquefaction. Final report, September 20, 1988--November 20, 1990

    SciTech Connect

    Serio, M.A.; Solomon, P.R.; Kroo, E.; Charpenay, S.; Bassilakis, R.

    1991-12-17

    The overall objective of the program was to improve the understanding of retrograde reactions and their dependencies on coal rank and structure, and/or coal modifications and reaction conditions. Because retrograde reactions are competitive with bond breaking reactions, an understanding of both is required to shift the competition in favor of the latter. Related objectives were to clarify the conflicting observations reported in literature on such major topics as the role of oxygen groups in retrograde reactions and to provide a bridge from very fundamental studies on pure compounds to phenomenological studies on actual coal. This information was integrated into the FG-DVC model, which was improved and extended to the liquefaction context.

  13. Retrograded maize starch used as a medium to enrich Monascus from the air in winter.

    PubMed

    Liu, Lizeng; Wang, Danli; Lian, Xijun; Wu, Hong

    2014-06-01

    Red pigments extracted from fungus Monascus are used for food coloration in China. Wild-growing Monascus spores are usually enriched in the yeast and mold media in the air, but those media are also favorable for yeast and bacteria. In the paper, Monascus species have grown in retrograded maize starch lain in air outdoors in winter, molds, yeast or bacteria colonies have been absent. Then a medium of the retrograded maize starch for enriching Monascus in the air is explored and its physicochemical properties are determined by ordinary camera photos, NMR, SEM spectra and X-ray diffraction. The lamellar structure of frozen retrograded maize starch, whose interlamellar spacing is about 2μm, provides a favorable condition for Monascus spore to germinate and grow. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Retrograde diurnal motion of the instantaneous rotation axis observed by a large ring laser gyroscope

    NASA Astrophysics Data System (ADS)

    Tian, W.

    2017-01-01

    Ring laser gyroscope technique directly senses the Earth's instantaneous rotation pole (IRP), whose polar motion contains strong retrograde diurnal components induced by external torques due to the gravitational attraction of the Moon and Sun. The first direct measurement of this retrograde diurnal motion with three large ring lasers was reported by Schreiber et al. (J Geophys Res 109(B18):B06405, significant increase in precision and stability of ring laser gyroscopes; however, precise determination of amplitude and phase at main partial waves has not been given in the literature. In this paper, I will report on determination of the retrograde diurnal motion of the IRP at main partial waves (Oo_1, J_1, K_1, M_1, O_1, Q_1) by the ring laser "G", located in Wettzell, Germany, which is the most stable one amongst the currently running large ring laser gyroscopes.

  15. Balloon-occluded retrograde transvenous obliteration for recurrent fundal gastric variceal bleeding in an adolescent.

    PubMed

    Rosen, Danya; Chu, Jaime; Patel, Rahul; Moon, Jang; Iyer, Kishore; Arnon, Ronen

    2014-09-01

    Gastric variceal bleeding is associated with high morbidity and mortality. Balloon-occluded retrograde transvenous obliteration is a relatively new treatment used to control bleeding gastric varices that involves transvenous sclerosis of gastric varices through a spontaneous gastrorenal shunt. Here, we report on a 14-yr-old patient that underwent balloon-occluded retrograde transvenous obliteration for refractory bleeding fundal varices in the setting of esophageal varices and cirrhosis, which did not respond to medical management or endoscopic injection. This case report serves as a reminder that balloon-occluded retrograde transvenous obliteration can successfully control fundal variceal bleeding in pediatric patients and may serve as a bridge to liver transplantation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Mycalolide B dissociates dynactin and abolishes retrograde axonal transport of dense-core vesicles.

    PubMed

    Cavolo, Samantha L; Zhou, Chaoming; Ketcham, Stephanie A; Suzuki, Matthew M; Ukalovic, Kresimir; Silverman, Michael A; Schroer, Trina A; Levitan, Edwin S

    2015-07-15

    Axonal transport is critical for maintaining synaptic transmission. Of interest, anterograde and retrograde axonal transport appear to be interdependent, as perturbing one directional motor often impairs movement in the opposite direction. Here live imaging of Drosophila and hippocampal neuron dense-core vesicles (DCVs) containing a neuropeptide or brain-derived neurotrophic factor shows that the F-actin depolymerizing macrolide toxin mycalolide B (MB) rapidly and selectively abolishes retrograde, but not anterograde, transport in the axon and the nerve terminal. Latrunculin A does not mimic MB, demonstrating that F-actin depolymerization is not responsible for unidirectional transport inhibition. Given that dynactin initiates retrograde transport and that amino acid sequences implicated in macrolide toxin binding are found in the dynactin component actin-related protein 1, we examined dynactin integrity. Remarkably, cell extract and purified protein experiments show that MB induces disassembly of the dynactin complex. Thus imaging selective retrograde transport inhibition led to the discovery of a small-molecule dynactin disruptor. The rapid unidirectional inhibition by MB suggests that dynactin is absolutely required for retrograde DCV transport but does not directly facilitate ongoing anterograde DCV transport in the axon or nerve terminal. More generally, MB's effects bolster the conclusion that anterograde and retrograde axonal transport are not necessarily interdependent. © 2015 Cavolo et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  17. Analysis of articulation between clathrin and retromer in retrograde sorting on early endosomes.

    PubMed

    Popoff, Vincent; Mardones, Gonzalo A; Bai, Siau-Kun; Chambon, Valérie; Tenza, Danièle; Burgos, Patricia V; Shi, Anbing; Benaroch, Philippe; Urbé, Sylvie; Lamaze, Christophe; Grant, Barth D; Raposo, Graça; Johannes, Ludger

    2009-12-01

    Clathrin and retromer have key functions for retrograde trafficking between early endosomes and the trans-Golgi network (TGN). Previous studies on Shiga toxin suggested that these two coat complexes operate in a sequential manner. Here, we show that the curvature recognition subunit component sorting nexin 1 (SNX1) of retromer interacts with receptor-mediated endocytosis-8 (RME-8) protein, and that RME-8 and SNX1 colocalize on early endosomes together with a model cargo of the retrograde route, the receptor-binding B-subunit of Shiga toxin (STxB). RME-8 has previously been found to bind to the clathrin uncoating adenosine triphosphatase (ATPase) Hsc70, and we now report that depletion of RME-8 or Hsc70 affects retrograde trafficking at the early endosomes-TGN interface of STxB and the cation-independent mannose 6-phosphate receptor, an endogenous retrograde cargo protein. We also provide evidence that retromer interacts with the clathrin-binding protein hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs) not only via SNX1, as previously published (Chin Raynor MC, Wei X, Chen HQ, Li L. Hrs interacts with sorting nexin 1 and regulates degradation of epidermal growth factor receptor. J Biol Chem 2001;276:7069-7078), but also via the core complex component Vps35. Hrs codistributes at the ultrastructural level with STxB on early endosomes, and interfering with Hrs function using antibodies or mild overexpression inhibits retrograde transport. Our combined data suggest a model according to which the functions in retrograde sorting on early endosomes of SNX1/retromer and clathrin are articulated by RME-8, and possibly also by Hrs.

  18. Retrograde Gene Delivery to Hypoglossal Motoneurons Using Adeno-Associated Virus Serotype 9

    PubMed Central

    ElMallah, Mai K.; Falk, Darin J.; Lane, Michael A.; Conlon, Thomas J.; Lee, Kun-Ze; Shafi, Nadeem I.; Reier, Paul J.

    2012-01-01

    Abstract Retrograde viral transport (i.e., muscle to motoneuron) enables targeted gene delivery to specific motor pools. Recombinant adeno-associated virus serotype 9 (AAV9) robustly infects motoneurons, but the retrograde transport capabilities of AAV9 have not been systematically evaluated. Accordingly, we evaluated the retrograde transduction efficiency of AAV9 after direct tongue injection in 129SVE mice as well as a mouse model that displays neuromuscular pathology (Gaa−/−). Hypoglossal (XII) motoneurons were histologically evaluated 8 weeks after tongue injection with AAV9 encoding green fluorescent protein (GFP) with expression driven by the chicken β-actin promoter (1×1011 vector genomes). On average, GFP expression was detected in 234±43 XII motoneurons 8 weeks after AAV9-GFP tongue injection. In contrast, tongue injection with a highly efficient retrograde anatomical tracer (cholera toxin β subunit, CT-β) resulted in infection of 818±88 XII motoneurons per mouse. The retrograde transduction efficiency of AAV9 was similar between the 129SVE mice and those with neuromuscular disease (Gaa−/−). Routine hematoxylin and eosin staining and cluster of differentiation (CD) immunostaining for T cells (CD3) indicated no persistent inflammation within the tongue or XII nucleus after AAV9 injection. Additional experiments indicated no adverse effects of AAV9 on the pattern of breathing. We conclude that AAV9 can retrogradely infect a significant portion of a given motoneuron pool in normal and dystrophic mice, and that its transduction efficiency is approximately 30% of what can be achieved with CT-β. PMID:22693957

  19. Twelve months follow-up after retrograde recanalization of superficial femoral artery chronic total occlusion

    PubMed Central

    Wojtasik-Bakalarz, Joanna; Arif, Salech; Chyrchel, Michał; Rakowski, Tomasz; Bartuś, Krzysztof; Dudek, Dariusz

    2017-01-01

    Introduction Fifty percent of cases of peripheral artery disease are caused by chronic total occlusion (CTO) of the superficial femoral artery (SFA). Ten–fifteen percent of percutaneous SFA recanalization procedures are unsuccessful. In those cases the retrograde technique can increase the success rate of the procedure, but the long-term follow-up of such procedures is still unknown. Aim To assess the efficacy and clinical outcomes during long-term follow-up after retrograde recanalization of the SFA. Material and methods We included patients after at least one unsuccessful percutaneous antegrade recanalization of the SFA. Patients were evaluated for the procedural and clinical follow-up of mean time 13.9 months. Results The study included 17 patients (7 females, 10 males) who underwent percutaneous retrograde recanalization of the SFA from June 2011 to June 2015. The mean age of patients was 63 ±7 years. Retrograde puncture of the distal SFA was successful in all cases. A retrograde procedure was performed immediately after antegrade failure in 4 (23.5%) patients and after a previously failed attempt in 13 (76.5%) patients. The procedure was successful in 15 (88.2%) patients, and unsuccessful in 2 (11.8%) patients. Periprocedural complications included 1 peripheral distal embolization (successfully treated with aspiration thrombectomy), 1 bleeding event from the puncture site and 7 puncture site hematomas. During follow-up the all-cause mortality rate was 5.8% (1 patient, non-cardiac death). The primary patency rate at 12 months was 88.2% and secondary patency 100%. Conclusions The retrograde SFA puncture seems to be a safe and successful technique for CTO recanalization and is associated with a low rate of perioperative and long-term follow-up complications. PMID:28344617

  20. A novel fluorescent retrograde neural tracer: cholera toxin B conjugated carbon dots

    NASA Astrophysics Data System (ADS)

    Zhou, Nan; Hao, Zeyu; Zhao, Xiaohuan; Maharjan, Suraj; Zhu, Shoujun; Song, Yubin; Yang, Bai; Lu, Laijin

    2015-09-01

    The retrograde neuroanatomical tracing method is a key technique to study the complex interconnections of the nervous system. Traditional tracers have several drawbacks, including time-consuming immunohistochemical or immunofluorescent staining procedures, rapid fluorescence quenching and low fluorescence intensity. Carbon dots (CDs) have been widely used as a fluorescent bio-probe due to their ultrasmall size, excellent optical properties, chemical stability, biocompatibility and low toxicity. Herein, we develop a novel fluorescent neural tracer: cholera toxin B-carbon dot conjugates (CTB-CDs). It can be taken up and retrogradely transported by neurons in the peripheral nervous system of rats. Our results show that CTB-CDs possess high photoluminescence intensity, good optical stability, a long shelf-life and non-toxicity. Tracing with CTB-CDs is a direct and more economical way of performing retrograde labelling experiments. Therefore, CTB-CDs are reliable fluorescent retrograde tracers.The retrograde neuroanatomical tracing method is a key technique to study the complex interconnections of the nervous system. Traditional tracers have several drawbacks, including time-consuming immunohistochemical or immunofluorescent staining procedures, rapid fluorescence quenching and low fluorescence intensity. Carbon dots (CDs) have been widely used as a fluorescent bio-probe due to their ultrasmall size, excellent optical properties, chemical stability, biocompatibility and low toxicity. Herein, we develop a novel fluorescent neural tracer: cholera toxin B-carbon dot conjugates (CTB-CDs). It can be taken up and retrogradely transported by neurons in the peripheral nervous system of rats. Our results show that CTB-CDs possess high photoluminescence intensity, good optical stability, a long shelf-life and non-toxicity. Tracing with CTB-CDs is a direct and more economical way of performing retrograde labelling experiments. Therefore, CTB-CDs are reliable fluorescent retrograde

  1. Brachial artery retrograde flow increases with age: relationship to physical function

    PubMed Central

    Credeur, Daniel P.; Dobrosielski, Devon A.; Arce-Esquivel, Arturo A.; Welsch, Michael A.

    2010-01-01

    The purpose of this study was to examine the flow velocity pattern of the brachial artery and to determine its relationship to measures of physical function. Subjects from the Louisiana Healthy Aging Study (n = 95; age = 84 ± 10 years) were evaluated. Brachial artery flow velocities and dimensions were measured using high-resolution ultrasonography. The continuous scale of physical function and performance test (CS-PFP10) was used to assess physical function. This test is based on the performance of 11 activities of daily living. Total CS-PFP10 score was 39.51 ± 21.21 U. Mean antegrade and retrograde velocities at rest were 14.2 ± 4.7 and 3.6 ± 2.2 cm/s, respectively. Ante-/retrograde ratio was 5.5 ± 4.6. Brachial artery diameter was 4.3 ± 0.7 mm. Pulse pressure and vascular conductance were 66 ± 18 mmHg, and 0.9 ± 0.5 ml/min/mmHg, respectively. Vascular conductance (r = −0.34), ante-/retrograde ratio (r = −0.42) and CS-PFP10 (r = −0.65) were inversely and retrograde velocity (r = 0.40) and pulse pressure (r = 0.36), were directly associated with age. Retrograde velocity was inversely related to vascular conductance (r = −0.27) and CS-PFP10 total score (r = −0.45). A MANOVA revealed that those with the higher CS-PFP10 scores had a lower retrograde velocity (P = 0.0001), but this association was, in part, age-dependent. Among nonagenarians (n = 52), those in the lower tertiles of the CS-PFP10 scores had significantly higher retrograde velocities compared to those in the higher tertiles (P = 0.035). These data indicate an increase in brachial retrograde velocity with age. These hemodynamic changes are related to a decline in physical function. PMID:19565260

  2. The Orbital Evolution of 2007 VA85, an Amor-type Asteroid on a Retrograde Orbit.

    NASA Astrophysics Data System (ADS)

    Kankiewicz, P.; Włodarczyk, I.

    2010-06-01

    Among the known population of asteroids on retrograde orbits (i > 90°) we found an object classified as an Amor-type asteroid. During the analysis of the first results of astrometry, we found some possible Earth-impact solutions for this asteroid. After taking into account the latest observations, we excluded any significant impact solution. However, this asteroid is the first known example of potentially hazardous object on a retrograde orbit. We also investigated the orbital evolution of 2007 VA85 (1 My in the past), obtaining possible scenarios of its dynamical origin.

  3. Antibiotic prophylaxis for patients undergoing elective endoscopic retrograde cholangiopancreatography.

    PubMed

    Brand, Martin; Bizos, Damon; O'Farrell, Peter

    2010-10-06

    The use of prophylactic antibiotics before endoscopic retrograde cholangiopancreatography (ERCP) is recommended by all major international gastroenterological societies, especially in the presence of an obstructed biliary system. Their use is intended to decrease or eliminate the incidence of complications following the procedure, namely cholangitis, cholecystitis, septicaemia, and pancreatitis. To assess the benefits and harms of antibiotics before elective ERCP in patients without evidence of acute or chronic cholecystitis, or acute or chronic cholangitis, or severe acute pancreatitis. We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and LILACS until March 2010. Relevant medical and surgical international conference proceedings were also searched. Only randomised clinical trials were included in the analyses, irrespective of blinding, language, or publication status. Participants were patients that underwent elective ERCP that were not on antibiotics, without evidence of acute or chronic cholecystitis, cholangitis, or severe acute pancreatitis before the procedure. We compared patients that received prophylactic antibiotics before the procedure with patients that were given placebo or no intervention before the procedure. The review was conducted according to the recommendations of The Cochrane Collaboration as well as the Cochrane Hepato-Biliary Group. Review Manager 5 was used employing fixed-effect and random-effects models meta-analyses. Nine randomised clinical trials (1573 patients) were included in the analyses. The majority of the trials had risks of bias. When all patients providing data for a certain outcome were included, the fixed-effect meta-analyses significantly favoured the use of prophylactic antibiotics in preventing cholangitis (relative risk (RR) 0.54, 95% CI 0.33 to 0.91), septicaemia

  4. Sustained inhibition of brotizolam induced anterograde amnesia by norharmane and retrograde amnesia by L-glutamic acid in mice.

    PubMed

    Anand, Akshay; Saraf, Manish Kumar; Prabhakar, Sudesh

    2007-08-22

    Benzodiazepines such as diazepam, lorazepam, are reported to produce anterograde amnesia but these do not affect the retrieval mechanism. Triazodiazepines such as alprazolam, triazolam and brotizolam produce both anterograde and retrograde amnesia. Because benzodiazepine receptor antagonists are known to reverse anterograde amnesia, we wanted to test if inverse agonist can also improve learning and memory. The present study was designed to investigate the effect of norharmane (benzodiazepine receptor inverse agonist) and L-glutamic acid (glutamate receptor agonist) on brotizolam induced anterograde and retrograde amnesia using Morris water maze task in mice. Norharmane reversed anterograde amnesia induced by brotizolam and did not reverse retrograde amnesia induced by it. L-Glutamic acid attenuated retrograde amnesia but did not affect anterograde amnesia induced by brotizolam. These results provide an opportunity to understand the mechanisms of anterograde and retrograde amnesia which may occur with interaction of presynaptic molecules or LTP modulation.

  5. Retrograde shear rate in formerly preeclamptic and healthy women before and after exercise training: relationship with endothelial function.

    PubMed

    Scholten, Ralph R; Spaanderman, Marc E A; Green, Daniel J; Hopman, Maria T E; Thijssen, Dick H J

    2014-08-01

    Blood flow patterns in conduit arteries characterized by high levels of retrograde shear stress can be detrimental for vascular health. In this study we examined whether retrograde shear rate and endothelial function are related in healthy and formerly preeclamptic (PE) women and whether this relationship is altered by exercise training. Formerly PE women (32 ± 4 yr, n = 20) and controls (32 ± 4 yr, n = 20), all 6-12 mo postpartum, performed 12-wk aerobic exercise training. We measured brachial artery shear rate (SR) and endothelial function by flow-mediated dilation (FMD, echo-Doppler). We additionally performed power spectral analysis of heart rate variability and calculated low-frequency/high-frequency (LF/HF) ratio. Antegrade SR was not different between groups, while retrograde SR was significantly higher and FMD% lower in PE women compared with controls (both P < 0.05). Retrograde shear correlated strongly with FMD% in PE women and controls (P < 0.05). LF/HF ratio inversely correlated with brachial artery retrograde SR and FMD% (both P < 0.05) in PE women and controls. Exercise training reduced retrograde shear, improved FMD%, and reduced LF/HF ratios similarly in both groups (all P < 0.05). Training-induced changes in retrograde SR correlated with changes in FMD% and LF/HF ratio. A higher brachial artery retrograde SR relates to lower brachial artery endothelial function, in both controls and formerly PE women. Exercise training improves retrograde SR, while the magnitude of this change correlated strongly with improvements in FMD and reductions in LF/HF ratio. Therefore, the impact of PE and exercise training on endothelial health may, at least partly, be related to retrograde shear rate.

  6. Effect of cross-linking degree on selected properties of retrograded starch adipate.

    PubMed

    Kapelko, M; Zięba, T; Michalski, A; Gryszkin, A

    2015-01-15

    The aim of this study was to determine the effects of the concentration of paste used to produce retrograded starch, and esterification degree, on selected properties of the resultant distarch adipate. Starch paste was prepared from native potato starch (1, 4, 10, 18 or 30 g/100g), frozen, defrosted and dried. Thus produced preparations of retrograded starch were cross-linked with various doses of a cross-linking agent (0.125, 0.25, 0.5, 1.0 or 2.0 ml per 100g of starch). Properties of the produced adipates depended on both the concentration of paste used to produce retrograded starch and the degree of substitution with adipic acid residues. Solubility in water and swelling power of the cross-linked preparations of retrograded starch, as well as pasting temperature and viscosity of produced pastes, all decreased along with the increasing degree of substitution with adipic acid residues. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Behavioral and Functional Neuroanatomical Correlates of Anterograde Autobiographical Memory in Isolated Retrograde Amnesic Patient M. L.

    ERIC Educational Resources Information Center

    Levine, Brian; Svoboda, Eva; Turner, Gary R.; Mandic, Marina; Mackey, Allison

    2009-01-01

    Patient M. L. [Levine, B., Black, S. E., Cabeza, R., Sinden, M., Mcintosh, A. R., Toth, J. P., et al. (1998). "Episodic memory and the self in a case of isolated retrograde amnesia." "Brain", "121", 1951-1973], lost memory for events occurring before his severe traumatic brain injury, yet his anterograde (post-injury) learning and memory appeared…

  8. A Hands-on Exploration of the Retrograde Motion of Mars as Seen from the Earth

    ERIC Educational Resources Information Center

    Pincelli, M. M.; Otranto, S.

    2013-01-01

    In this paper, we propose a set of activities based on the use of a celestial simulator to gain insights into the retrograde motion of Mars as seen from the Earth. These activities provide a useful link between the heliocentric concepts taught in schools and those tackled in typical introductory physics courses based on classical mechanics for…

  9. A comparison of Er, Cr: YSGG laser with ultrasonic preparation on the seal of retrograde cavities

    PubMed Central

    Roghanizad, Nasrin; Kalhori, Katayoun AM; Khalilak, Zohreh; Esmaeili, Maryam Ali; de Fatima Zanirato Lizarelli, Rosane

    2015-01-01

    Background and aim: The aim of this in vitro study was to compare Er, Cr: YSGG laser with ultrasonic preparation on the seal of retrograde cavities. Materials and methods: Twenty-eight maxillary anterior teeth were used in this study. After removing the crowns, the canals were prepared with the step-back technique and filled with guttapercha. Three millimeters below the apex; each root was cut with a fissure diamond bur. The root surfaces were then covered with nail polish and three millimeters deep retrograde class I cavities were prepared, using Er, Cr: YSGG laser (group L=12 roots) or ultrasonic retro-tip (group U=12 roots). Four roots were arranged for negative and positive control groups. Retrograde cavities were then filled with mineral trioxide aggregate (MTA) and teeth were placed in 2% methylene blue dye for 72 hours. The amount of dye penetration in sagittal sections of each tooth was measured with a stereomicroscope. An independent sample t-test was used for statistical analysis. Results: Cavities prepared with the Er, Cr: YSGG laser (1.61 + 0.81) showed significantly less micro-leakage than those prepared with the ultrasound (2.55+ 1.84) (P value =0.02). Conclusions: Under the conditions of this research, the use of Er, Cr: YSGG laser for retrograde cavity preparation causes significantly less apical leakage and may increase the success rate of endodontic surgeries. PMID:25941423

  10. Structure of waxy maize starch hydrolyzed by maltogenic alpha-amylase in relation to its retrogradation

    USDA-ARS?s Scientific Manuscript database

    Maltogenic a-amylase is widely used as an antistaling agent in bakery foods. The objective of this study was to determine the degree of hydrolysis (DH) and starch structure after maltogenic amylase treatments in relation to its retrogradation. Waxy maize starch was cooked and hydrolyzed to different...

  11. Modal Selection Analysis of Depot Level Reparable Asset Retrograde Shipments Within the Continental United States

    DTIC Science & Technology

    2003-03-14

    21 Review of Modal Choice Theory Relative to the Civilian Sector...choice in the Air Force retrograde logistics pipeline, the focus of this particular thesis. 26 Review of Modal Choice Theory Relative to the...However, the author feels it is at least noteworthy to introduce some of the nuances of modal choice theory as it relates to the civilian sector. A

  12. [Subcapsular hepatic hematoma after endoscopic retrograde cholangiopancreatography: case report and literature review].

    PubMed

    Petit-Laurent, Fabien; Scalone, Olivia; Penigaud, Marianne; Barbeys, Jean

    2007-01-01

    Subcapsular hepatic hematoma is a rare complication of endoscopic retrograde cholangiopancreatography. The mechanism of this lesion has not been clearly established. The following observation clarifies the physiopathology, as well as providing a review of the various cases described in the literature.

  13. A Hands-on Exploration of the Retrograde Motion of Mars as Seen from the Earth

    ERIC Educational Resources Information Center

    Pincelli, M. M.; Otranto, S.

    2013-01-01

    In this paper, we propose a set of activities based on the use of a celestial simulator to gain insights into the retrograde motion of Mars as seen from the Earth. These activities provide a useful link between the heliocentric concepts taught in schools and those tackled in typical introductory physics courses based on classical mechanics for…

  14. Retrogradation behavior of corn starch treated with 1,4-α-glucan branching enzyme.

    PubMed

    Li, Wenwen; Li, Caiming; Gu, Zhengbiao; Qiu, Yijing; Cheng, Li; Hong, Yan; Li, Zhaofeng

    2016-07-15

    The retrogradation behavior of corn starch treated with 1,4-α-glucan branching enzyme (GBE) was investigated using rheometry, pulsed nuclear magnetic resonance (PNMR), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). Dynamic time sweep analysis confirmed that the storage modulus (G') of corn starch stored at 4 °C decreased with increasing GBE treatment time. PNMR analysis demonstrated that the transverse relaxation times (T2) of corn starches treated with GBE were higher than that of control during the storage at 4 °C. DSC results demonstrated that the retrogradation enthalpy (ΔHr) of corn starch was reduced by 22.3% after GBE treatment for 10h. Avrami equation analysis showed that GBE treatment reduced the rate of starch retrogradation. FTIR analysis revealed that GBE treatment led to a decrease in hydrogen bonds within the starch. Overall, these results demonstrate that both short- and long-term retrogradation of corn starch were retarded by GBE treatment.

  15. Effects of HIV-1 Nef on retrograde transport from the plasma membrane to the endoplasmic reticulum.

    PubMed

    Johannes, Ludger; Pezo, Valérie; Mallard, Frédéric; Tenza, Danièle; Wiltz, Aimée; Saint-Pol, Agnès; Helft, Julie; Antony, Claude; Benaroch, Philippe

    2003-05-01

    HIV-1 Nef protein down-regulates several important immunoreceptors through interactions with components of the intracellular sorting machinery. Nef expression is also known to induce modifications of the endocytic pathway. Here, we analyzed the effects of Nef on retrograde transport, from the plasma membrane to the endoplasmic reticulum using Shiga toxin B-subunit (STxB). Nef expression inhibited access of STxB to the endoplasmic reticulum, but did not modify the surface expression level of STxB receptor, Gb3, nor its internalization rate as measured with a newly developed assay. Mutation of the myristoylation site or of a di-leucine motif of Nef involved in the interaction with the clathrin adaptor complexes AP1 and AP2 abolished the inhibition of retrograde transport. In contrast, mutations of Nef motifs known to interact with PACS-1, beta COP or a subunit of the v-ATPase did not modify the inhibitory activity of Nef on retrograde transport. Ultrastructural analysis revealed that Nef was present in clusters located on endosomal or Golgi membranes together with internalized STxB. Furthermore, in strongly Nef-expressing cells, STxB accumulated in endosomal structures that labeled with AP1. Our observations show that Nef perturbs retrograde transport between the early endosome and the endoplasmic reticulum. The potential transport steps targeted by Nef are discussed.

  16. Effect of phospholipids transesterified enzymatically with polyunsaturated fatty acids on gelatinization and retrogradation of starch.

    PubMed

    Siswoyo, L A; Morita, N

    2000-10-01

    The effects of phospholipids (PLs) transesterified with polyunsaturated fatty acids (PUFAs) with lipase (Aspergillus niger) on gelatinization and retrogradation of starch during storage were studied by differential scanning calorimetry (DSC). The resulting transesterified PLs were rich in PUFAs and linoleic acid, while the total percentage of PUFAs incorporated was 20.2%. The addition of PLs or PLs enzymatically transesterified with PUFAs (PUFA-PLs) to the starch sample decreased the gelatinization enthalpy of starch (deltah(g)) slightly, but clearly increased the starch-lipid complexes (deltah(s-1)) by DSC. After 21 days of storage, the percent of retrogradation of starch became lower by the addition of 4%, PLs or 4% PUFA-PLs to the starch sample when compared with the control. These results suggest that PLs retard retrogradation of starch during storage, whereas PUFA-PLs retard it greatly. The addition of PLs or PUFA-PLs increased the amount of deltah(s-1), while re-gelatinization enthalpy decreased during storage, which suggests that PLs or PUFA-PLs could retard the retrogradation of starch.

  17. Self-repair in a bidirectionally coupled astrocyte-neuron (AN) system based on retrograde signaling

    PubMed Central

    Wade, John; McDaid, Liam; Harkin, Jim; Crunelli, Vincenzo; Kelso, Scott

    2012-01-01

    In this paper we demonstrate that retrograde signaling via astrocytes may underpin self-repair in the brain. Faults manifest themselves in silent or near silent neurons caused by low transmission probability (PR) synapses; the enhancement of the transmission PR of a healthy neighboring synapse by retrograde signaling can enhance the transmission PR of the “faulty” synapse (repair). Our model of self-repair is based on recent research showing that retrograde signaling via astrocytes can increase the PR of neurotransmitter release at damaged or low transmission PR synapses. The model demonstrates that astrocytes are capable of bidirectional communication with neurons which leads to modulation of synaptic activity, and that indirect signaling through retrograde messengers such as endocannabinoids leads to modulation of synaptic transmission PR. Although our model operates at the level of cells, it provides a new research direction on brain-like self-repair which can be extended to networks of astrocytes and neurons. It also provides a biologically inspired basis for developing highly adaptive, distributed computing systems that can, at fine levels of granularity, fault detect, diagnose and self-repair autonomously, without the traditional constraint of a central fault detect/repair unit. PMID:23055965

  18. Structure of Waxy Maize Starch Hydrolyzed by Maltogenic α-Amylase in Relation to Its Retrogradation.

    PubMed

    Grewal, Navneet; Faubion, Jon; Feng, Guohua; Kaufman, Rhett C; Wilson, Jeff D; Shi, Yong-Cheng

    2015-04-29

    Maltogenic α-amylase is widely used as an antistaling agent in bakery foods. The objective of this study was to determine the degree of hydrolysis (DH) and starch structure after maltogenic amylase treatments in relation to its retrogradation. Waxy maize starch was cooked and hydrolyzed to different degrees by a maltogenic amylase. High-performance anion-exchange chromatography and size exclusion chromatography were used to determine saccharides formed and the molecular weight (Mw) distributions of the residual starch structure, respectively. Chain length (CL) distributions of debranched starch samples were further related to amylopectin (AP) retrogradation. Differential scanning calorimetry (DSC) results showed the complete inhibition of retrogradation when starches were hydrolyzed to >20% DH. Mw and CL distributions of residual AP structure indicated that with an increase in %DH, a higher proportion of unit chains with degree of polymerization (DP) ≤9 and a lower proportion of unit chains with DP ≥17 were formed. A higher proportion of short outer AP chains that cannot participate in the formation of double helices supports the decrease in and eventual inhibition of retrogradation observed with the increase in %DH. These results suggest that the maltogenic amylase could play a powerful role in inhibiting the staling of baked products even at limited starch hydrolysis.

  19. In vitro analyses of resistant starch in retrograded waxy and normal corn starches.

    PubMed

    Zhou, Xing; Chung, Hyun-Jung; Kim, Jong-Yea; Lim, Seung-Taik

    2013-04-01

    Gelatinized waxy and normal corn starches (40% starch) were subjected to temperature cycling between 4 and 30°C (1 day at each temperature) or isothermal storage (4°C) to induce retrogradation. The in vitro analysis methods that are currently used for the measurement of resistant starch (RS), i.e. Englyst, AACC 32-40 and Goni methods, were compared with homogenized retrograded starch gels and freeze-dried powders of the gels. RS contents obtained by the three analysis methods were in the following order: Goni>Englyst>AACC. Although different RS values were obtained among the analysis methods, similar trends in regards to the starch type and storage conditions could be observed. Little or no RS was found in freeze-dried powders of the retrograded starch gels and storage conditions had no effect, indicating that the physical state for RS analysis is important. More RS was found in normal corn starch gels than in waxy corn starch gels under identical storage conditions and in the gels stored under temperature cycling than those under isothermal storage (4°C), indicating that the presence of amylose inhibits starch digestion and the level of crystalline structure of re-crystallized amylopectin also affects the RS formation during retrogradation.

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

    PubMed Central

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

    2011-01-01

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

  1. Mitochondrial retrograde signaling induces epithelial-mesenchymal transition and generates breast cancer stem cells.

    PubMed

    Guha, M; Srinivasan, S; Ruthel, G; Kashina, A K; Carstens, R P; Mendoza, A; Khanna, C; Van Winkle, T; Avadhani, N G

    2014-11-06

    Metastatic breast tumors undergo epithelial-to-mesenchymal transition (EMT), which renders them resistant to therapies targeted to the primary cancers. The mechanistic link between mtDNA (mitochondrial DNA) reduction, often seen in breast cancer patients, and EMT is unknown. We demonstrate that reducing mtDNA content in human mammary epithelial cells (hMECs) activates Calcineurin (Cn)-dependent mitochondrial retrograde signaling pathway, which induces EMT-like reprogramming to fibroblastic morphology, loss of cell polarity, contact inhibition and acquired migratory and invasive phenotype. Notably, mtDNA reduction generates breast cancer stem cells. In addition to retrograde signaling markers, there is an induction of mesenchymal genes but loss of epithelial markers in these cells. The changes are reversed by either restoring the mtDNA content or knockdown of CnAα mRNA, indicating the causal role of retrograde signaling in EMT. Our results point to a new therapeutic strategy for metastatic breast cancers targeted to the mitochondrial retrograde signaling pathway for abrogating EMT and attenuating cancer stem cells, which evade conventional therapies. We report a novel regulatory mechanism by which low mtDNA content generates EMT and cancer stem cells in hMECs.

  2. On Common Ground: Jost's (1897) Law of Forgetting and Ribot's (1881) Law of Retrograde Amnesia

    ERIC Educational Resources Information Center

    Wixted, John T.

    2004-01-01

    T. Ribot's (1881) law of retrograde amnesia states that brain damage impairs recently formed memories to a greater extent than older memories, which is generally taken to imply that memories need time to consolidate. A. Jost's (1897) law of forgetting states that if 2 memories are of the same strength but different ages, the older will decay more…

  3. Lrp4 is a retrograde signal for presynaptic differentiation at neuromuscular synapses.

    PubMed

    Yumoto, Norihiro; Kim, Natalie; Burden, Steven J

    2012-09-20

    Motor axons receive retrograde signals from skeletal muscle that are essential for the differentiation and stabilization of motor nerve terminals. Identification of these retrograde signals has proved elusive, but their production by muscle depends on the receptor tyrosine kinase, MuSK (muscle, skeletal receptor tyrosine-protein kinase), and Lrp4 (low-density lipoprotein receptor (LDLR)-related protein 4), an LDLR family member that forms a complex with MuSK, binds neural agrin and stimulates MuSK kinase activity. Here we show that Lrp4 also functions as a direct muscle-derived retrograde signal for early steps in presynaptic differentiation. We demonstrate that Lrp4 is necessary, independent of MuSK activation, for presynaptic differentiation in vivo, and we show that Lrp4 binds to motor axons and induces clustering of synaptic-vesicle and active-zone proteins. Thus, Lrp4 acts bidirectionally and coordinates synapse formation by binding agrin, activating MuSK and stimulating postsynaptic differentiation, and functioning in turn as a muscle-derived retrograde signal that is necessary and sufficient for presynaptic differentiation.

  4. The planetary increase of brightness during retrograde motion: An explanandum constructed ad explanantem.

    PubMed

    Carman, Christián Carlos

    2015-12-01

    In Ancient Greek two models were proposed for explaining the planetary motion: the homocentric spheres of Eudoxus and the Epicycle and Deferent System. At least in a qualitative way, both models could explain the retrograde motion, the most challenging phenomenon to be explained using circular motions. Nevertheless, there is another explanandum: during retrograde motion the planets increase their brightness. It is natural to interpret a change of brightness, i.e., of apparent size, as a change in distance. Now, while according to the Eudoxian model the planet is always equidistant from the earth, according to the epicycle and deferent system, the planet changes its distance from the earth, approaching to it during retrograde motion, just as observed. So, it is usually affirmed that the main reason for the rejection of Eudoxus' homocentric spheres in favor of the epicycle and deferent system was that the first cannot explain the manifest planetary increase of brightness during retrograde motion, while the second can. In this paper I will show that this historical hypothesis is not as firmly founded as it is usually believed to be. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Superselective retrograde lymphatic duct embolization for management of postoperative lymphatic leak.

    PubMed

    Arslan, Bülent; Masrani, Abdulrahman; Tasse, Jordan Cameron; Stenson, Kerstin; Turba, Ülkü Cenk

    2017-01-01

    Lymphatic leak is a well-documented complication following neck dissection surgeries. When conservative methods fail to control the leak, thoracic duct embolization becomes an option. Transabdominal access is the standard for this procedure; however, it is not always feasible. We discuss a technique of selective lymphatic vessel embolization utilizing retrograde transvenous access.

  6. Superselective retrograde lymphatic duct embolization for management of postoperative lymphatic leak

    PubMed Central

    Arslan, Bülent; Masrani, Abdulrahman; Tasse, Jordan Cameron; Stenson, Kerstin; Turba, Ülkü Cenk

    2017-01-01

    Lymphatic leak is a well-documented complication following neck dissection surgeries. When conservative methods fail to control the leak, thoracic duct embolization becomes an option. Transabdominal access is the standard for this procedure; however, it is not always feasible. We discuss a technique of selective lymphatic vessel embolization utilizing retrograde transvenous access. PMID:28724508

  7. Behavioral and Functional Neuroanatomical Correlates of Anterograde Autobiographical Memory in Isolated Retrograde Amnesic Patient M. L.

    ERIC Educational Resources Information Center

    Levine, Brian; Svoboda, Eva; Turner, Gary R.; Mandic, Marina; Mackey, Allison

    2009-01-01

    Patient M. L. [Levine, B., Black, S. E., Cabeza, R., Sinden, M., Mcintosh, A. R., Toth, J. P., et al. (1998). "Episodic memory and the self in a case of isolated retrograde amnesia." "Brain", "121", 1951-1973], lost memory for events occurring before his severe traumatic brain injury, yet his anterograde (post-injury) learning and memory appeared…

  8. Compatibility of DAPl and silver staining for combined anterograde and retrograde tracing of neural connections.

    PubMed

    Rhoades, R W

    1980-11-10

    The geniculocortical and corticogeniculate pathways in hamster were used to test the compatibility of 4'6 diamidino-2 phenylindole 2HCl (DAPl)6,10 and anterograde degeneration techniques for tracing reciprocal connections in the brain. The two methods were compatible within a single brain and, with some loss of sensitivity in the retrograde labeling, within a single section.

  9. The role of the dynein light intermediate chain in retrograde IFT and flagellar function in Chlamydomonas.

    PubMed

    Reck, Jaimee; Schauer, Alexandria M; VanderWaal Mills, Kristyn; Bower, Raqual; Tritschler, Douglas; Perrone, Catherine A; Porter, Mary E

    2016-08-01

    The assembly of cilia and flagella depends on the activity of two microtubule motor complexes, kinesin-2 and dynein-2/1b, but the specific functions of the different subunits are poorly defined. Here we analyze Chlamydomonas strains expressing different amounts of the dynein 1b light intermediate chain (D1bLIC). Disruption of D1bLIC alters the stability of the dynein 1b complex and reduces both the frequency and velocity of retrograde intraflagellar transport (IFT), but it does not eliminate retrograde IFT. Flagellar assembly, motility, gliding, and mating are altered in a dose-dependent manner. iTRAQ-based proteomics identifies a small subset of proteins that are significantly reduced or elevated in d1blic flagella. Transformation with D1bLIC-GFP rescues the mutant phenotypes, and D1bLIC-GFP assembles into the dynein 1b complex at wild-type levels. D1bLIC-GFP is transported with anterograde IFT particles to the flagellar tip, dissociates into smaller particles, and begins processive retrograde IFT in <2 s. These studies demonstrate the role of D1bLIC in facilitating the recycling of IFT subunits and other proteins, identify new components potentially involved in the regulation of IFT, flagellar assembly, and flagellar signaling, and provide insight into the role of D1bLIC and retrograde IFT in other organisms.

  10. Phytochrome and retrograde signalling pathways converge to antagonistically regulate a light-induced transcriptional network.

    PubMed

    Martín, Guiomar; Leivar, Pablo; Ludevid, Dolores; Tepperman, James M; Quail, Peter H; Monte, Elena

    2016-05-06

    Plastid-to-nucleus retrograde signals emitted by dysfunctional chloroplasts impact photomorphogenic development, but the molecular link between retrograde- and photosensory-receptor signalling has remained unclear. Here, we show that the phytochrome and retrograde signalling (RS) pathways converge antagonistically to regulate the expression of the nuclear-encoded transcription factor GLK1, a key regulator of a light-induced transcriptional network central to photomorphogenesis. GLK1 gene transcription is directly repressed by PHYTOCHROME-INTERACTING FACTOR (PIF)-class bHLH transcription factors in darkness, but light-activated phytochrome reverses this activity, thereby inducing expression. Conversely, we show that retrograde signals repress this induction by a mechanism independent of PIF mediation. Collectively, our data indicate that light at moderate levels acts through the plant's nuclear-localized sensory-photoreceptor system to induce appropriate photomorphogenic development, but at excessive levels, sensed through the separate plastid-localized RS system, acts to suppress such development, thus providing a mechanism for protection against photo-oxidative damage by minimizing the tissue exposure to deleterious radiation.

  11. F-actin polymerization and retrograde flow drive sustained PLCγ1 signaling during T cell activation

    PubMed Central

    Babich, Alexander; Li, Shuixing; O'Connor, Roddy S.; Milone, Michael C.; Freedman, Bruce D.

    2012-01-01

    Activation of T cells by antigen-presenting cells involves assembly of signaling molecules into dynamic microclusters (MCs) within a specialized membrane domain termed the immunological synapse (IS). Actin and myosin IIA localize to the IS, and depletion of F-actin abrogates MC movement and T cell activation. However, the mechanisms that coordinate actomyosin dynamics and T cell receptor signaling are poorly understood. Using pharmacological inhibitors that perturb individual aspects of actomyosin dynamics without disassembling the network, we demonstrate that F-actin polymerization is the primary driver of actin retrograde flow, whereas myosin IIA promotes long-term integrity of the IS. Disruption of F-actin retrograde flow, but not myosin IIA contraction, arrested MC centralization and inhibited sustained Ca2+ signaling at the level of endoplasmic reticulum store release. Furthermore, perturbation of retrograde flow inhibited PLCγ1 phosphorylation within MCs but left Zap70 activity intact. These studies highlight the importance of ongoing actin polymerization as a central driver of actomyosin retrograde flow, MC centralization, and sustained Ca2+ signaling. PMID:22665519

  12. Reexposure to the Amnestic Agent Alleviates Cycloheximide-Induced Retrograde Amnesia for Reactivated and Extinction Memories

    ERIC Educational Resources Information Center

    Briggs, James F.; Olson, Brian P.

    2013-01-01

    We investigated whether reexposure to an amnestic agent would reverse amnesia for extinction of learned fear similar to that of a reactivated memory. When cycloheximide (CHX) was administered immediately after a brief cue-induced memory reactivation (15 sec) and an extended extinction session (12 min) rats showed retrograde amnesia for both…

  13. Phytochrome and retrograde signalling pathways converge to antagonistically regulate a light-induced transcriptional network

    PubMed Central

    Martín, Guiomar; Leivar, Pablo; Ludevid, Dolores; Tepperman, James M.; Quail, Peter H.; Monte, Elena

    2016-01-01

    Plastid-to-nucleus retrograde signals emitted by dysfunctional chloroplasts impact photomorphogenic development, but the molecular link between retrograde- and photosensory-receptor signalling has remained unclear. Here, we show that the phytochrome and retrograde signalling (RS) pathways converge antagonistically to regulate the expression of the nuclear-encoded transcription factor GLK1, a key regulator of a light-induced transcriptional network central to photomorphogenesis. GLK1 gene transcription is directly repressed by PHYTOCHROME-INTERACTING FACTOR (PIF)-class bHLH transcription factors in darkness, but light-activated phytochrome reverses this activity, thereby inducing expression. Conversely, we show that retrograde signals repress this induction by a mechanism independent of PIF mediation. Collectively, our data indicate that light at moderate levels acts through the plant's nuclear-localized sensory-photoreceptor system to induce appropriate photomorphogenic development, but at excessive levels, sensed through the separate plastid-localized RS system, acts to suppress such development, thus providing a mechanism for protection against photo-oxidative damage by minimizing the tissue exposure to deleterious radiation. PMID:27150909

  14. The role of the dynein light intermediate chain in retrograde IFT and flagellar function in Chlamydomonas

    PubMed Central

    Reck, Jaimee; Schauer, Alexandria M.; VanderWaal Mills, Kristyn; Bower, Raqual; Tritschler, Douglas; Perrone, Catherine A.; Porter, Mary E.

    2016-01-01

    The assembly of cilia and flagella depends on the activity of two microtubule motor complexes, kinesin-2 and dynein-2/1b, but the specific functions of the different subunits are poorly defined. Here we analyze Chlamydomonas strains expressing different amounts of the dynein 1b light intermediate chain (D1bLIC). Disruption of D1bLIC alters the stability of the dynein 1b complex and reduces both the frequency and velocity of retrograde intraflagellar transport (IFT), but it does not eliminate retrograde IFT. Flagellar assembly, motility, gliding, and mating are altered in a dose-dependent manner. iTRAQ-based proteomics identifies a small subset of proteins that are significantly reduced or elevated in d1blic flagella. Transformation with D1bLIC-GFP rescues the mutant phenotypes, and D1bLIC-GFP assembles into the dynein 1b complex at wild-type levels. D1bLIC-GFP is transported with anterograde IFT particles to the flagellar tip, dissociates into smaller particles, and begins processive retrograde IFT in <2 s. These studies demonstrate the role of D1bLIC in facilitating the recycling of IFT subunits and other proteins, identify new components potentially involved in the regulation of IFT, flagellar assembly, and flagellar signaling, and provide insight into the role of D1bLIC and retrograde IFT in other organisms. PMID:27251063

  15. Reexposure to the Amnestic Agent Alleviates Cycloheximide-Induced Retrograde Amnesia for Reactivated and Extinction Memories

    ERIC Educational Resources Information Center

    Briggs, James F.; Olson, Brian P.

    2013-01-01

    We investigated whether reexposure to an amnestic agent would reverse amnesia for extinction of learned fear similar to that of a reactivated memory. When cycloheximide (CHX) was administered immediately after a brief cue-induced memory reactivation (15 sec) and an extended extinction session (12 min) rats showed retrograde amnesia for both…

  16. Influence of chronic endurance exercise training on conduit artery retrograde and oscillatory shear in older adults.

    PubMed

    Casey, Darren P; Schneider, Aaron C; Ueda, Kenichi

    2016-10-01

    With aging, there tends to be an increase in retrograde and oscillatory shear in peripheral conduit arteries of humans. Whether the increase in shear rate is due to the aging process or an effect of a less active lifestyle that often accompanies aging is unknown. Therefore, we examined whether chronic endurance exercise training attenuates conduit artery retrograde and oscillatory shear in older adults. Brachial and common femoral artery mean blood velocities and diameter were determined via Doppler ultrasound under resting conditions, and shear rate was calculated in 13 young (24 ± 2 years), 17 older untrained (66 ± 3 years), and 16 older endurance exercise-trained adults (66 ± 7 years). Brachial artery retrograde (-9.1 ± 6.4 vs. -12.6 ± 9.4 s(-1); P = 0.35) and oscillatory (0.14 ± 0.08 vs. 0.14 ± 0.08 arbitrary units; P = 0.99) shear were similar between the older trained and untrained groups, whereas brachial artery retrograde and oscillatory shear were greater in older untrained compared to young adults (-5.0 ± 3.4, 0.08 ± 0.05 s(-1) arbitrary units, P = 0.017 and 0.048, respectively). There was no difference between the young and older trained brachial retrograde (P = 0.29) and oscillatory (P = 0.07) shear. Common femoral artery retrograde (-6.3 ± 2.9 s(-1)) and oscillatory (0.21 ± 0.08 arbitrary units) shear were reduced in older trained compared to the older untrained group (-10.4 ± 4.1 and 0.30 ± 0.09 s(-1) arbitrary units, both P = 0.005 and 0.006, respectively), yet similar to young adults (-7.1 ± 3.5 and 0.19 ± 0.06 s(-1) arbitrary units, P = 0.81 and 0.87, respectively). Our results suggest that chronic endurance exercise training in older adults ameliorates retrograde and oscillatory shear rate patterns, particularly in the common femoral artery.

  17. Influence of chronic endurance exercise training on conduit artery retrograde and oscillatory shear in older adults

    PubMed Central

    Schneider, Aaron C.; Ueda, Kenichi

    2017-01-01

    Purpose With aging, there tends to be an increase in retrograde and oscillatory shear in peripheral conduit arteries of humans. Whether the increase in shear rate is due to the aging process or an effect of a less active lifestyle that often accompanies aging is unknown. Therefore, we examined whether chronic endurance exercise training attenuates conduit artery retrograde and oscillatory shear in older adults. Methods Brachial and common femoral artery mean blood velocities and diameter were determined via Doppler ultrasound under resting conditions, and shear rate was calculated in 13 young (24 ± 2 years), 17 older untrained (66 ± 3 years), and 16 older endurance exercise-trained adults (66 ± 7 years). Results Brachial artery retrograde (−9.1 ± 6.4 vs. −12.6 ± 9.4 s−1; P = 0.35) and oscillatory (0.14 ± 0.08 vs. 0.14 ± 0.08 arbitrary units; P = 0.99) shear were similar between the older trained and untrained groups, whereas brachial artery retrograde and oscillatory shear were greater in older untrained compared to young adults (−5.0 ± 3.4, 0.08 ± 0.05 s−1 arbitrary units, P = 0.017 and 0.048, respectively). There was no difference between the young and older trained brachial retrograde (P = 0.29) and oscillatory (P = 0.07) shear. Common femoral artery retrograde (−6.3 ± 2.9 s−1) and oscillatory (0.21 ± 0.08 arbitrary units) shear were reduced in older trained compared to the older untrained group (−10.4 ± 4.1 and 0.30 ± 0.09 s−1 arbitrary units, both P = 0.005 and 0.006, respectively), yet similar to young adults (−7.1 ± 3.5 and 0.19 ± 0.06 s−1 arbitrary units, P = 0.81 and 0.87, respectively). Conclusion Our results suggest that chronic endurance exercise training in older adults ameliorates retrograde and oscillatory shear rate patterns, particularly in the common femoral artery. PMID:27497720

  18. Partial melting during exhumation of Paleozoic retrograde eclogite in North Qaidam, western China

    NASA Astrophysics Data System (ADS)

    Cao, Yu-ting; Liu, Liang; Chen, Dan-ling; Wang, Chao; Yang, Wen-qiang; Kang, Lei; Zhu, Xiao-hui

    2017-10-01

    Ultrahigh pressure (UHP) rocks are often overprinted by high pressure (HP) granulite-facies metamorphism during exhumation. Here we investigate retrograde eclogite from the Lvliangshan area in North Qaidam which is associated with abundant felsic veins. The eclogite adjacent to the vein shows conversion to garnet amphibolite. Petrographic, mineralogical, geochemical, geochronological data suggest that the eclogite has been experienced peak eclogite facies metamorphism at c. 440 Ma, followed by granulite facies retrogression at c. 420 Ma, and amphibolite facies overprinting at <420 Ma. The retrograde eclogite has microstructural records for partial melting with elongated plagioclase grains occurring as veinlets along the garnet-ilmenite grain boundaries and interspersed in clinopyroxene. Moreover, highly cuspate, wedge-shaped and triangular plagioclase grains are distributed along the garnet boundaries, and banded felsic veins (Pl + Qz) occur along the boundaries of amphibole in garnet amphibolite. Whole-rock geochemistry suggests that the felsic veins have 438.1-1106 ppm Sr and 2.87-12.18 ppm Y with Sr/Y ratios from 81.98-166.2, exhibit pronounced positive Eu anomaly, and depletion of HREE, resembling those of adakitic rocks. Felsic veins contain zircon grains with an U-Pb age of ∼422 Ma, similar to the age of HP granulite-facies metamorphism (420 Ma) of retrograde eclogite. Combined with the identical Hf isotope compositions between the granulite-facies zircon grains from the host retrograde eclogite and those from the felsic vein, we infer closed system partial melting during HP granulite facies retrogression of the retrograde eclogite. The tonalitic (high Sr/Y ratio and enrichment of LREE) chemical feature, low Rb/Sr and high Ba/Rb ratios of the felsic veins suggest that zoisite and sodic amphibolite dehydration-melting together account for the formation of felsic veins during exhumation from the eclogite-facies to granulite-facies stages.

  19. Continuous butanol fermentation and feed starch retrogradation: butanol fermentation sustainability using Clostridium beijerinckii BA101.

    PubMed

    Ezeji, T C; Qureshi, N; Blaschek, H P

    2005-01-26

    Use of starch solution as feed for butanol bioconversion processes employing Clostridium beijerinckii BA101 may have added economic advantage over the use of glucose. Acetone butanol ethanol (ABE) was produced from 30 gL(-1) starch solution using a continuous process. The bioreactor was fed at a dilution rate of 0.02 h(-1) and starch solution/feed volume (3 L) was replaced every 72 h. The continuous reactor fed with cornstarch solution (feed temperature 19 degrees C) produced approximately 6.0 gL(-1) total ABE. Increasing the feed storage temperature to 37 degrees C improved ABE production to 7.2 gL(-1) suggesting that retrogradation was occurring more rapidly at 19 degrees C. In both these cases the fermentation drifted toward acid production after approximately 260 h, consistent with the retrogradation of starch overtime. The use of soluble starch, which is less prone to retrogradation, resulted in the production of 9.9 gL(-1) ABE at 37 degrees C feed storage temperature, as compared to 7.2 gL(-1) ABE when cornstarch was used. It should be noted that gelatinized starch retrogradation takes place after sterilization and prior to use of the feed medium, and does not occur during long-term storage of the raw corn material in the months leading up to processing. The degree of hydrolysis of gelatinized starch decreased from 68.8 to 56.2% in 3 days when stored at 37 degrees C. Soluble starch which does not retrograde demonstrated no change in the degree of hydrolysis.

  20. Non-Cell-Autonomous Regulation of Retrograde Motoneuronal Axonal Transport in an SBMA Mouse Model

    PubMed Central

    Halievski, Katherine; Kemp, Michael Q.; Breedlove, S. Marc; Miller, Kyle E.

    2016-01-01

    Abstract Defects in axonal transport are seen in motoneuronal diseases, but how that impairment comes about is not well understood. In spinal bulbar muscular atrophy (SBMA), a disorder linked to a CAG/polyglutamine repeat expansion in the androgen receptor (AR) gene, the disease-causing AR disrupts axonal transport by acting in both a cell-autonomous fashion in the motoneurons themselves, and in a non-cell-autonomous fashion in muscle. The non-cell-autonomous mechanism is suggested by data from a unique “myogenic” transgenic (TG) mouse model in which an AR transgene expressed exclusively in skeletal muscle fibers triggers an androgen-dependent SBMA phenotype, including defects in retrograde transport. However, motoneurons in this TG model retain the endogenous AR gene, leaving open the possibility that impairments in transport in this model also depend on ARs in the motoneurons themselves. To test whether non-cell-autonomous mechanisms alone can perturb retrograde transport, we generated male TG mice in which the endogenous AR allele has the testicular feminization mutation (Tfm) and, consequently, is nonfunctional. Males carrying the Tfm allele alone show no deficits in motor function or axonal transport, with or without testosterone treatment. However, when Tfm males carrying the myogenic transgene (Tfm/TG) are treated with testosterone, they develop impaired motor function and defects in retrograde transport, having fewer retrogradely labeled motoneurons and deficits in endosomal flux based on time-lapse video microscopy of living axons. These findings demonstrate that non-cell-autonomous disease mechanisms originating in muscle are sufficient to induce defects in retrograde transport in motoneurons. PMID:27517091

  1. Non-Cell-Autonomous Regulation of Retrograde Motoneuronal Axonal Transport in an SBMA Mouse Model.

    PubMed

    Halievski, Katherine; Kemp, Michael Q; Breedlove, S Marc; Miller, Kyle E; Jordan, Cynthia L

    2016-01-01

    Defects in axonal transport are seen in motoneuronal diseases, but how that impairment comes about is not well understood. In spinal bulbar muscular atrophy (SBMA), a disorder linked to a CAG/polyglutamine repeat expansion in the androgen receptor (AR) gene, the disease-causing AR disrupts axonal transport by acting in both a cell-autonomous fashion in the motoneurons themselves, and in a non-cell-autonomous fashion in muscle. The non-cell-autonomous mechanism is suggested by data from a unique "myogenic" transgenic (TG) mouse model in which an AR transgene expressed exclusively in skeletal muscle fibers triggers an androgen-dependent SBMA phenotype, including defects in retrograde transport. However, motoneurons in this TG model retain the endogenous AR gene, leaving open the possibility that impairments in transport in this model also depend on ARs in the motoneurons themselves. To test whether non-cell-autonomous mechanisms alone can perturb retrograde transport, we generated male TG mice in which the endogenous AR allele has the testicular feminization mutation (Tfm) and, consequently, is nonfunctional. Males carrying the Tfm allele alone show no deficits in motor function or axonal transport, with or without testosterone treatment. However, when Tfm males carrying the myogenic transgene (Tfm/TG) are treated with testosterone, they develop impaired motor function and defects in retrograde transport, having fewer retrogradely labeled motoneurons and deficits in endosomal flux based on time-lapse video microscopy of living axons. These findings demonstrate that non-cell-autonomous disease mechanisms originating in muscle are sufficient to induce defects in retrograde transport in motoneurons.

  2. Contraction of the Ventral Abdomen Potentiates Extracardiac Retrograde Hemolymph Propulsion in the Mosquito Hemocoel

    PubMed Central

    Andereck, Jonathan W.; King, Jonas G.; Hillyer, Julián F.

    2010-01-01

    Background Hemolymph circulation in mosquitoes is primarily controlled by the contractile action of a dorsal vessel that runs underneath the dorsal midline and is subdivided into a thoracic aorta and an abdominal heart. Wave-like peristaltic contractions of the heart alternate in propelling hemolymph in anterograde and retrograde directions, where it empties into the hemocoel at the terminal ends of the insect. During our analyses of hemolymph propulsion in Anopheles gambiae, we observed periodic ventral abdominal contractions and hypothesized that they promote extracardiac hemolymph circulation in the abdominal hemocoel. Methodology/Principal Findings We devised methods to simultaneously analyze both heart and abdominal contractions, as well as to measure hemolymph flow in the abdominal hemocoel. Qualitative and quantitative analyses revealed that ventral abdominal contractions occur as series of bursts that propagate in the retrograde direction. Periods of ventral abdominal contraction begin only during periods of anterograde heart contraction and end immediately following a heartbeat directional reversal, suggesting that ventral abdominal contractions function to propel extracardiac hemolymph in the retrograde direction. To test this functional role, fluorescent microspheres were intrathoracically injected and their trajectory tracked throughout the hemocoel. Quantitative measurements of microsphere movement in extracardiac regions of the abdominal cavity showed that during periods of abdominal contractions hemolymph flows in dorsal and retrograde directions at a higher velocity and with greater acceleration than during periods of abdominal rest. Histochemical staining of the abdominal musculature then revealed that ventral abdominal contractions result from the contraction of intrasegmental lateral muscle fibers, intersegmental ventral muscle bands, and the ventral transverse muscles that form the ventral diaphragm. Conclusions/Significance These data show that

  3. Contraction of the ventral abdomen potentiates extracardiac retrograde hemolymph propulsion in the mosquito hemocoel.

    PubMed

    Andereck, Jonathan W; King, Jonas G; Hillyer, Julián F

    2010-09-23

    Hemolymph circulation in mosquitoes is primarily controlled by the contractile action of a dorsal vessel that runs underneath the dorsal midline and is subdivided into a thoracic aorta and an abdominal heart. Wave-like peristaltic contractions of the heart alternate in propelling hemolymph in anterograde and retrograde directions, where it empties into the hemocoel at the terminal ends of the insect. During our analyses of hemolymph propulsion in Anopheles gambiae, we observed periodic ventral abdominal contractions and hypothesized that they promote extracardiac hemolymph circulation in the abdominal hemocoel. We devised methods to simultaneously analyze both heart and abdominal contractions, as well as to measure hemolymph flow in the abdominal hemocoel. Qualitative and quantitative analyses revealed that ventral abdominal contractions occur as series of bursts that propagate in the retrograde direction. Periods of ventral abdominal contraction begin only during periods of anterograde heart contraction and end immediately following a heartbeat directional reversal, suggesting that ventral abdominal contractions function to propel extracardiac hemolymph in the retrograde direction. To test this functional role, fluorescent microspheres were intrathoracically injected and their trajectory tracked throughout the hemocoel. Quantitative measurements of microsphere movement in extracardiac regions of the abdominal cavity showed that during periods of abdominal contractions hemolymph flows in dorsal and retrograde directions at a higher velocity and with greater acceleration than during periods of abdominal rest. Histochemical staining of the abdominal musculature then revealed that ventral abdominal contractions result from the contraction of intrasegmental lateral muscle fibers, intersegmental ventral muscle bands, and the ventral transverse muscles that form the ventral diaphragm. These data show that abdominal contractions potentiate extracardiac retrograde

  4. Control of Autophagosome Axonal Retrograde Flux by Presynaptic Activity Unveiled Using Botulinum Neurotoxin Type A

    PubMed Central

    Wang, Tong; Martin, Sally; Papadopulos, Andreas; Harper, Callista B.; Mavlyutov, Timur A.; Niranjan, Dhevahi; Glass, Nick R.; Cooper-White, Justin J.; Sibarita, Jean-Baptiste; Choquet, Daniel; Davletov, Bazbek; Meunier, Frédéric A.

    2015-01-01

    Botulinum neurotoxin type A (BoNT/A) is a highly potent neurotoxin that elicits flaccid paralysis by enzymatic cleavage of the exocytic machinery component SNAP25 in motor nerve terminals. However, recent evidence suggests that the neurotoxic activity of BoNT/A is not restricted to the periphery, but also reaches the CNS after retrograde axonal transport. Because BoNT/A is internalized in recycling synaptic vesicles, it is unclear which compartment facilitates this transport. Using live-cell confocal and single-molecule imaging of rat hippocampal neurons cultured in microfluidic devices, we show that the activity-dependent uptake of the binding domain of the BoNT/A heavy chain (BoNT/A-Hc) is followed by a delayed increase in retrograde axonal transport of BoNT/A-Hc carriers. Consistent with a role of presynaptic activity in initiating transport of the active toxin, activity-dependent uptake of BoNT/A in the terminal led to a significant increase in SNAP25 cleavage detected in the soma chamber compared with nonstimulated neurons. Surprisingly, most endocytosed BoNT/A-Hc was incorporated into LC3-positive autophagosomes generated in the nerve terminals, which then underwent retrograde transport to the cell soma, where they fused with lysosomes both in vitro and in vivo. Blocking autophagosome formation or acidification with wortmannin or bafilomycin A1, respectively, inhibited the activity-dependent retrograde trafficking of BoNT/A-Hc. Our data demonstrate that both the presynaptic formation of autophagosomes and the initiation of their retrograde trafficking are tightly regulated by presynaptic activity. PMID:25878289

  5. Does Slow Slip and Tremor Require High Fluid Pressure? Thoughts From Observations in Retrograde Faults

    NASA Astrophysics Data System (ADS)

    Fagereng, A.; Diener, J. F. A.; Stenvall, C.

    2016-12-01

    Subduction zone tremor and slow slip appear spatially correlated with elevated pore fluid pressures related to prograde dehydration reactions in water-saturated subducting rocks. However, tremor and slow slip have also been observed in other tectonic settings, notably on the San Andreas and Alpine faults, where displacement of previously dehydrated rocks occurs along trajectories of decreasing temperature and pressure. Here, fluids are not produced by local dehydration reactions, and external fluids introduced to the fault may be consumed by retrograde hydration reactions. Thus, we suggest that tremor and slow slip in retrograde shear zones imply weakening and strain localization without high fluid pressures, and test this hypothesis against observations in an exhumed, retrograde, continental shear zone. The Kuckaus Mylonite Zone (KMZ), Namibia, accommodated crustal scale strike-slip displacement of granitoid gneisses and migmatites at 450 - 480°C and 270 - 420 MPa, conditions representative of the continuation of continental fault zones below the base of the crustal seismogenic zone. High strain zones within the KMZ comprise fine grained retrograde mineral assemblages requiring rehydration of the original high temperature mineral assemblages in the host rock. Lack of local fluid sources implies that rehydration required influx of an external fluid. We see only minor evidence for hydrothermal vein formation related to this fluid, but note metasomatic alteration and local evidence for dissolution-precipitation. We propose that the main contribution of the fault zone fluid was to allow growth of retrograde, weak, mineral phases, and facilitate grain size reduction through nucleation of new grains, activating grain-size sensitive creep at low driving stresses. Tremor and slow slip observed on active faults under similar conditions may also not require high fluid pressures, but rather be explained by reaction weakening under hydrostatic fluid pressure conditions.

  6. Retrograde blood flow in the brachial and axillary arteries during routine radial arterial catheter flushing.

    PubMed

    Murphy, Glenn S; Szokol, Joseph W; Marymont, Jesse H; Avram, Michael J; Vender, Jeffery S; Kubasiak, John

    2006-09-01

    Flushing of radial arterial catheters may be associated with retrograde embolization of air or thrombus into the cerebral circulation. For embolization into the central circulation to occur, sufficient pressure must be generated during the flushing process to reverse antegrade blood flow in the arterial blood vessels of the upper extremity. This ultrasound study was designed to examine whether routine radial catheter flushing practices produce retrograde blood flow patterns in the brachial and proximal axillary arteries. Duplex ultrasound examinations of the brachial and axillary arteries were conducted in 100 surgical patients to quantify direction and velocity of blood flow during catheter flushing. After obtaining Doppler spectral images of brachial and axillary arterial flow patterns, manual flushing was performed by injecting 10 ml flush solution using a syringe at a rate reflecting standard clinical practices. The flow-regulating device on the pressurized (300 mmHg) arterial flushing-sampling system was then opened for 10 s to deliver a rapid bolus of fluid (flush valve opening). The rate of manual flush solution injection through the radial arterial catheter was related to the probability of retrograde flow in the axillary artery (P < 0.001). Reversed arterial flow was noted in the majority of subjects (33 of 51) at a manual flush rate of less than 9 s and in no subjects (0 of 48) at a rate 9 s or greater. Retrograde flow was observed less frequently during flush valve opening (2 of 99 patients; P < 0.001 vs. manual flushing). Rapid manual flushing of radial arterial catheters at rates faster than 1 ml/s produces retrograde flow in the proximal axillary artery.

  7. Morphology and Immunoreactivity of Retrogradely Double-Labeled Ganglion Cells in the Mouse Retina

    PubMed Central

    Wu, Samuel M.

    2011-01-01

    Purpose. To examine the specificity and reliability of a retrograde double-labeling technique that was recently established for identification of retinal ganglion cells (GCs) and to characterize the morphology of displaced (d)GCs (dGs). Methods. A mixture of the gap-junction–impermeable dye Lucifer yellow (LY) and the permeable dye neurobiotin (NB) was applied to the optic nerve stump for retrograde labeling of GCs and the cells coupled with them. A confocal microscope was adopted for morphologic observation. Results. GCs were identified by LY labeling, and they were all clearly labeled by NB. Cells coupled to GCs contained a weak NB signal but no LY. LY and NB revealed axon bundles, somas and dendrites of GCs. The retrogradely identified GCs numbered approximately 50,000 per retina, and they constituted 44% of the total neurons in the ganglion cell layer (GCL). Somas of retrogradely identified dGs were usually negative for glycine, ChAT (choline acetyltransferase), bNOS (brain-type nitric oxidase), GAD (glutamate decarboxylase), and glial markers, and occasionally, they were weakly GABA-positive. dGs averaged 760 per retina and composed 1.7% of total GCs. Sixteen morphologic subtypes of dGs were encountered, three of which were distinct from known GCs. dGs sent dendrites to either sublaminas of the IPL, mostly sublamina a. Conclusions. The retrograde labeling is reliable for identification of GCs. dGs participate in ON and OFF light pathways but favor the OFF pathway. ChAT, bNOS, glycine, and GAD remain reliable AC markers in the GCL. GCs may couple to GABAergic ACs, and the gap junctions likely pass NB and GABA. PMID:21482641

  8. Retrograde Intramedullary Nailing for Humerus Fracture in a Supine Position: Performing an Unfamiliar Procedure in a Familiar Position.

    PubMed

    Yi, Jin Woong; Lee, Jae Sin; Cho, Hyung Jun

    2017-09-01

    Intramedullary (IM) nailing for humeral shaft fracture has provided excellent outcomes in terms of fracture biology and cosmetic appearance because of the relatively small incision involved. However, antegrade nailing causes issues such as iatrogenic rotator cuff injury. Retrograde nail fixation method could avoid cuff injury, but has shortcomings such as the need for the prone or lateral decubitus position during surgery. We report that the retrograde IM nail fixation technique performed in a supine position and some ancillary techniques for minimizing scars or complications can provide the advantages of both retrograde nailing and supine position during surgery.

  9. [The evaluation of the retrograde memory in the Quebec population aged: PUB-40 and PUB-12].

    PubMed

    Langlois, Roxane; Joubert, Sven; Benoit, Sophie; Dostie, Valérie; Rouleau, Isabelle

    2015-09-01

    Memory assessment represents an important part of the clinical neuropsychologist's duties in a geriatric context. In fact, in Canada, about one-third of seniors report memory complaints, with different causes. Based on the underlying etiology, different components of memory may be affected in older adults. Nonautobiographical retrograde memory (public or semantic) is an important aspect of memory to assess; nevertheless, there is currently no reliable and standardized clinical tool to evaluate this aspect of memory in the elderly Quebecer population. The aims of this research were therefore: (1) to develop a protocol specifically aimed at assessing non-autobiographical retrograde memory in this population, the PUB-40; (2) to obtain reference data among 105 healthy subjects; and (3) to develop a short version based on the items which discriminated a group of 20 patients with amnestic Mild cognitive impairment (aMCI) from older healthy subjects.

  10. Effects of salts on the gelatinization and retrogradation properties of maize starch and waxy maize starch.

    PubMed

    Wang, Wei; Zhou, Hongxian; Yang, Hong; Zhao, Siming; Liu, Youming; Liu, Ru

    2017-01-01

    The objective of this study was to evaluate the effects of salts on the gelatinization and retrogradation of maize and waxy maize starch. Experimental results showed that the salting-out or structure-making ions, such as F(-) and SO4(2-), decreased the swelling power, solubility and transparency of both starches, but increased the gelatinization temperature, enthalpy, and syneresis, due to the tendency of these ions to protect the hydrogen bond links among starch molecules. On the other hand, the salting-in or structure-breaking ions, such as I(-) and SCN(-), exhibited the opposite effects. Microscopic observations confirmed such effects of salts on both starches. Furthermore, the effects of salts were more significant on waxy maize and on normal maize starch. Generally, salts could significantly influence on the gelatinization and retrogradation of maize and waxy maize starch, following the order of the Hofmeister series. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Retrograde accretion discs in high-mass Be/X-ray binaries

    NASA Astrophysics Data System (ADS)

    Christodoulou, D. M.; Laycock, S. G. T.; Kazanas, D.

    2017-09-01

    We have compiled a comprehensive library of all X-ray observations of Magellanic pulsars carried out by XMM-Newton, Chandra and RXTE in the period 1997-2014. In this work, we use the data from 53 high-mass Be/X-ray binaries in the Small Magellanic Cloud to demonstrate that the distribution of spin-period derivatives versus spin periods of spinning-down pulsars is not at all different from that of the accreting spinning-up pulsars. The inescapable conclusion is that the up and down samples were drawn from the same continuous parent population; therefore, Be/X-ray pulsars that are spinning down over periods spanning 18 yr are, in fact, accreting from retrograde discs. The presence of prograde and retrograde discs in roughly equal numbers supports a new evolutionary scenario for Be/X-ray pulsars in their spin period-period derivative diagram.

  12. Adrenocortical hemorrhagic necrosis: the role of catecholamines and retrograde medullary-cell embolism

    SciTech Connect

    Szabo, S.; McComb, D.J.; Kovacs, K.; Huettner, I.

    1981-10-01

    We investigated the pathogenesis of adrenal necrosis using animal models of the disease (induced by administration of acrylonitrile, cysteamine, or pyrazole) and human cases. Results of electron-microscopic and histochemical time-response studies with rat models revealed an early, retrograde embolization of medullary cells and cell fragments in the cortical capillaries that showed prominent endothelial injury. The experimental adrenal lesions were prevented by surgical removal of the medulla one month before administration of adrenocorticolytic chemicals, or by the administration of the alpha-adrenergic antagonist phenoxybenzamine hydrochloride. Histochemical staining for medullary (argyrophil) granules in human cases of adrenal necrosis demonstrated tissue fragments that stained positively for silver in vascular cortical spaces in nine of ten autopsy specimens and in all four surgical cases we reviewed. Thus, catecholamines released from the adrenal medulla and from the retrograde medullary emboli in the cortex may have a role in the pathogenesis of adrenocortical necrosis.

  13. CEUS Retrograde Cystography Is Helpful in Percutaneous Drainage of Complex Posttransplant Lymphocele.

    PubMed

    Di Domenico, Stefano; Patti, Valentina; Fazio, Federico; Moggia, Elisabetta; Fontana, Iris; Valente, Umberto

    2012-01-01

    After monolateral dual kidney transplantation, a 69 years old male patient developed symptomatic lymphocele with mild hydroureteronephrosis, impaired renal function, and right inferior limb oedema. A percutaneous ultrasound-guided drainage of the fluid collection was planned, but the complex mutual relations between the collection and the renal hilus did not allow to identify a suitable route for a safe drainage insertion during conventional ultrasound examination. A retrograde cystography using echographic contrast agent was, therefore, performed, and it clarified the position of both ureters and the renal vessels, permitting an harmless ultrasound-guided percutaneous lymphocele drainage. In conclusion contrast-enhanced ultrasound retrograde cystography may be helpful in percutaneous drainage of complex posttransplant lymphocele.

  14. LRRK2 regulates retrograde synaptic compensation at the Drosophila neuromuscular junction

    PubMed Central

    Penney, Jay; Tsurudome, Kazuya; Liao, Edward H.; Kauwe, Grant; Gray, Lindsay; Yanagiya, Akiko; R. Calderon, Mario; Sonenberg, Nahum; Haghighi, A. Pejmun

    2016-01-01

    Parkinson's disease gene leucine-rich repeat kinase 2 (LRRK2) has been implicated in a number of processes including the regulation of mitochondrial function, autophagy and endocytic dynamics; nevertheless, we know little about its potential role in the regulation of synaptic plasticity. Here we demonstrate that postsynaptic knockdown of the fly homologue of LRRK2 thwarts retrograde, homeostatic synaptic compensation at the larval neuromuscular junction. Conversely, postsynaptic overexpression of either the fly or human LRRK2 transgene induces a retrograde enhancement of presynaptic neurotransmitter release by increasing the size of the release ready pool of vesicles. We show that LRRK2 promotes cap-dependent translation and identify Furin 1 as its translational target, which is required for the synaptic function of LRRK2. As the regulation of synaptic homeostasis plays a fundamental role in ensuring normal and stable synaptic function, our findings suggest that aberrant function of LRRK2 may lead to destabilization of neural circuits. PMID:27432119

  15. Retrograde intubation in a case of ankylosing spondylitis posted for correction of deformity of spine

    PubMed Central

    Raval, Chetankumar; Patel, Heena; Patel, Pranoti; Kharod, Utpala

    2010-01-01

    Ankylosing spondylitis (AS) patients are most challenging. These patient present the most serious array of intubation and difficult airway imaginable, secondary to decrease or no cervical spine mobility, fixed flexion deformity of thoracolumbar spine and possible temporomandibular joint disease. Sound clinical judgment is critical for timing and selecting the method for airway intervention. The retrograde intubation technique is an important option when fiberoptic bronchoscope is not available, and other method is not applicable for gaining airway access for surgery in prone position. We report a case of AS with fixed flexion deformity of thoracic and thoracolumbar spine, fusion of posterior elements of cervical spine posted for lumbar spinal osteotomy with anticipated difficult intubation. An awake retrograde oral intubation with light sedation and local block is performed. PMID:20668567

  16. Effect of retrogradation time on preparation and characterization of proso millet starch nanoparticles.

    PubMed

    Sun, Qingjie; Gong, Min; Li, Ying; Xiong, Liu

    2014-10-13

    Starch nanoparticles were prepared from proso millet starch using a green and facile method combined with enzymolysis and recrystallization. Scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA) were used to characterize the morphology and crystal structure of the starch nanoparticles prepared with different retrogradation time (0.5, 4, 12, and 24h). The results showed that the sizes of the starch nanoparticles were between 20 nm and 100 nm. The crystal pattern changed from A-type (native starch) to B-type (nanoparticles), and the relative crystallinity of the nanoparticles increased obviously, as compared with the native starch. The nanoparticles prepared with the 12h retrogradation time had the highest degree of crystallinity (47.04%). Compared to conventional acid hydrolysis to make starch nanoparticles, the present approach has the advantage of being quite rapid and presenting a higher yield (about 55%).

  17. A light microscope-based double retrograde tracer strategy to chart central neuronal connections.

    PubMed

    Ruigrok, Tom J H; Apps, Richard

    2007-01-01

    This protocol describes a double retrograde tracing method to chart divergent projections in the CNS using light microscope techniques. It is based on immunohistochemical visualization of retrograde transport of cholera toxin b-subunit (CTb) and silver enhancement of a gold-lectin conjugate. Production of the gold-lectin is explained in detail, and a technique is offered to record through the injection pipettes, to help guide accurate placement of injections. Visualization of the two tracers results in light brown staining of CTb-labeled neurons and labeling by black particles of gold-lectin-containing neurons. Both types of label are easily recognized in the same neuron. The labeling is permanent and is well suited for studies in which large areas of the brain need to be surveyed. The whole procedure (excluding survival time) takes approximately 5-7 d to complete.

  18. Primary pulmonary artery sarcoma extending retrograde into the superior vena cava.

    PubMed

    Portillo-Sanchez, José; Hessein-Abdou, Yasser; Puga-Alcalde, Eugenio; Perez-Martinez, Maria Angeles; Del Carmen Jimenez-Meneses, Maria; Camacho-Pedrero, Agustín; Valdepeñas-Herrero, Luís Ruíz

    2011-01-01

    Primary pulmonary artery sarcoma is a rare tumor that is highly fatal. It can be misdiagnosed as acute or chronic pulmonary thromboembolic disease. Herein, we report the case of a 22-year-old woman with a preoperative diagnosis of pulmonary embolism and superior vena caval thrombosis. Intraoperatively, an extensive sarcoma was seen to extend retrograde from the pulmonary artery, past the right ventricle and right atrium, and into the superior vena cava. Surgical resection of the tumor and reconstruction of the central pulmonary arteries, followed by adjuvant chemotherapy, relieved the clinical symptoms. The patient remained free of cancer at 14 months postoperatively. We believe that this is the 1st report of a primary pulmonary artery sarcoma that extended retrograde into the superior vena cava.

  19. Retrograde axonal transport of ciliary neurotrophic factor is increased by peripheral nerve injury.

    PubMed

    Curtis, R; Adryan, K M; Zhu, Y; Harkness, P J; Lindsay, R M; DiStefano, P S

    1993-09-16

    Ciliary neurotrophic factor (CNTF) promotes the survival of several populations of neurons, including sensory and motor neurons. Although CNTF is abundant in adult sciatic nerve, the mature protein lacks a signal sequence and is not secreted; therefore, it has been proposed to act as a lesion factor. The identification of a functional CNTF receptor revealed ligand-specific phosphorylation cascades and gene induction. However, it is not clear how these signal-transducing events are elicited in neuronal cell bodies that may be distant from the source of CNTF. We report here that CNTF can be retrogradely transported by adult sensory neurons. More importantly, sensory and motor neurons both show greatly increased transport of CNTF following peripheral nerve lesion. Axotomy-induced increases in retrograde transport of neurotrophic factors may be an important response of neuronal cell bodies during regeneration.

  20. Air embolism after endoscopic retrograde cholangiopancreatography in a patient with budd Chiari syndrome.

    PubMed

    Wills-Sanin, Beatriz; Cárdenas, Yenny R; Polanco, Lucas; Rivero, Oscar; Suarez, Sebastian; Buitrago, Andrés F

    2014-01-01

    Endoscopic retrograde cholangiopancreatography is a procedure commonly used for the diagnosis and treatment of various pancreatic and biliary diseases. Air embolism is a rare complication, which may be associated with this procedure. This condition can be manifested as cardiopulmonary instability and/or neurological symptoms. Known risk factors include: sphincterotomy; application of air with high intramural pressure; anatomic abnormalities; and chronic hepatobiliary inflammation. It is important for the health-care staff, including anesthesiologists, interventional gastroenterologists, and critical care specialists, amongst others, to promptly recognize air embolism and to initiate therapy in a timely fashion, thus preventing potentially fatal outcomes. We submit a brief review of the literature and a case report of air embolism which occurred in the immediate postoperative stage of an endoscopic retrograde cholangiopancreatography, performed in a woman with a history of liver transplantation due to Budd Chiari syndrome and biliary stricture.

  1. Air Embolism after Endoscopic Retrograde Cholangiopancreatography in a Patient with Budd Chiari Syndrome

    PubMed Central

    Wills-Sanin, Beatriz; Cárdenas, Yenny R.; Polanco, Lucas; Rivero, Oscar; Suarez, Sebastian; Buitrago, Andrés F.

    2014-01-01

    Endoscopic retrograde cholangiopancreatography is a procedure commonly used for the diagnosis and treatment of various pancreatic and biliary diseases. Air embolism is a rare complication, which may be associated with this procedure. This condition can be manifested as cardiopulmonary instability and/or neurological symptoms. Known risk factors include: sphincterotomy; application of air with high intramural pressure; anatomic abnormalities; and chronic hepatobiliary inflammation. It is important for the health-care staff, including anesthesiologists, interventional gastroenterologists, and critical care specialists, amongst others, to promptly recognize air embolism and to initiate therapy in a timely fashion, thus preventing potentially fatal outcomes. We submit a brief review of the literature and a case report of air embolism which occurred in the immediate postoperative stage of an endoscopic retrograde cholangiopancreatography, performed in a woman with a history of liver transplantation due to Budd Chiari syndrome and biliary stricture. PMID:25478242

  2. Combined retrograde labeling and calcium imaging in spinal cord and brainstem neurons of the lamprey.

    PubMed

    McClellan, A D; McPherson, D; O'Donovan, M J

    1994-11-07

    Neurons in the brainstem and spinal cord of the lamprey were retrogradely labeled with Calcium Green-dextran, an indicator dye that increases its fluorescence when intracellular calcium levels increase. Optical signals could be recorded from these labeled neurons during spinal cord stimulation, nerve stimulation, or spontaneous activity, up to 4 days after dye application and for distances of 5-14 mm away from the application site. Optical signals were enhanced by 4-AP, a potassium channel blocker, and blocked by cadmium, a calcium channel blocker. Taken together, the results suggest that the optical signals recorded from labeled neurons were due to calcium influx during electrical activity. Thus, retrograde labeling with calcium indicator dyes may provide a general purpose method for simultaneously monitoring the activity-related changes of intracellular calcium in anatomically identified groups of neurons in the lamprey nervous system.

  3. How High Can You Go?: Retrograde Nailing of Proximal Femur Fractures.

    PubMed

    Kuhn, Kevin M; Cannada, Lisa K; Watson, J Tracy; Ali, Ashley; Boudreau, John A; Mir, Hassan R; Bauer, Jennifer M; Mullis, Brian; Hymes, Robert; Genova, Renee; Tucker, Michael; Schlatter, Daniel

    2017-01-01

    There are no data-supported recommendations on how proximal is too proximal for retrograde nailing (RGN). At six level 1 trauma centers, patients with femur fractures within the proximal one-third of the femur treated with RGN were included. This article describes a proximal segment capture ratio (PSCR) and nail segment capture ratio to evaluate RGN of proximal fractures. The study included 107 patients. The average follow-up was 44 weeks. There were two nonunions and three malunions. There was no significant difference between PSCR of 0.3 or less and need for secondary procedures or time to full weight bearing (p>.05). In this study, a smaller (< 0.3) PSCR was not associated with an increased number of complications. A higher Orthopaedic Trauma Association classification was predictive of malunion and increased time to union. These data demonstrate that retrograde nailing is safe and effective for the treatment of supraisthmal femur fractures.

  4. The electromotor system of the electric eel investigated with horseradish peroxidase as a retrograde tracer.

    PubMed

    Bennett, M V; Sandri, C

    1989-05-29

    The electromotor system of the electric eel, Electrophorus electricus, was studied by injection of horseradish peroxidase as a retrograde tracer. The electromotor neurons, which innervate the electrocytes, comprise a midline nucleus, largely dorsal to the spinal canal. Spinal motoneurons lie ventrolaterally. The electromotor and skeletal motor neuron populations correspond to the acetylcholinesterase-negative and -positive cells previously described. The medullary relay neurons were labeled following HRP injection into the spinal cord at a level where electromotor neurons occurred, but not after injection into the cord in the abdominal region rostral to these cells. Other medullary neurons, presumably bulbospinal motor fibers, were labeled after both levels of spinal cord injection. The results suggest that these axosomatic synapses, which are electrically transmitting but morphologically mixed, take up retrograde tracers in a manner similar to chemical synapses and that tracer uptake is at least largely at terminal regions.

  5. Trans-synaptic Retrograde Degeneration in the Human Visual System: Slow, Silent, and Real.

    PubMed

    Dinkin, Marc

    2017-02-01

    Degeneration of neuron and axons following injury to cells with which they synapse is termed trans-synaptic degeneration. This phenomenon may be seen in postsynaptic neurons (anterograde) or in presynaptic neurons (retrograde). Retrograde trans-synaptic degeneration (RTSD) of the retinal ganglion cells and retinal nerve fiber layer following injury to the occipital lobe has been well documented histologically in animal studies, but its occurrence in the human retina was, for many years, felt to be limited to cases of neonatal injury during a critical period of neuronal development. Over the last decade, imaging techniques such as MRI and optical coherence tomography have allowed us to visualize and quantify RTSD and analyze its time course and relationship to degree of vision loss and age of cortical injury. A deeper understanding of RTSD in the human visual system may allow us to interfere with its occurrence, potentially allowing for greater recovery following visual cortex injury.

  6. Dominant-negative myosin Va impairs retrograde but not anterograde axonal transport of large dense core vesicles.

    PubMed

    Bittins, Claudia Margarethe; Eichler, Tilo Wolf; Hammer, John A; Gerdes, Hans-Hermann

    2010-04-01

    Axonal transport of peptide and hormone-containing large dense core vesicles (LDCVs) is known to be a microtubule-dependent process. Here, we suggest a role for the actin-based motor protein myosin Va specifically in retrograde axonal transport of LDCVs. Using live-cell imaging of transfected hippocampal neurons grown in culture, we measured the speed, transport direction, and the number of LDCVs that were labeled with ectopically expressed neuropeptide Y fused to EGFP. Upon expression of a dominant-negative tail construct of myosin Va, a general reduction of movement in both dendrites and axons was observed. In axons, it was particularly interesting that the retrograde speed of LDCVs was significantly impaired, although anterograde transport remained unchanged. Moreover, particles labeled with the dominant-negative construct often moved in the retrograde direction but rarely in the anterograde direction. We suggest a model where myosin Va acts as an actin-dependent vesicle motor that facilitates retrograde axonal transport.

  7. Diagnostic and therapeutic role of endoscopic retrograde cholangiopancreatography in biliary rhabdomyosarcoma

    PubMed Central

    Himes, Ryan W; Raijman, Isaac; Finegold, Milton J; Russell, Heidi V; Fishman, Douglas S

    2008-01-01

    Biliary rhabdomyosarcoma (BRMS) is an uncommon childhood malignancy which has been managed surgically. We present a case of a 3-year-old boy with BRMS, in whom endoscopic retrograde cholangiopancreatography (ERCP) was successfully used both diagnostically and therapeutically, thus obviating the need for surgery and its attendant risks of morbidity and mortality. We conclude that ERCP is an effective alternative to surgery for BRMS in some patients. PMID:18720547

  8. Antidromic Atrioventricular Reciprocating Tachycardia Using a Concealed Retrograde Conducting Left Lateral Accessory Pathway.

    PubMed

    Gonzalez, Jaime E; Zipse, Matthew M; Nguyen, Duy T; Sauer, William H

    2016-03-01

    Atrioventricular reciprocating tachycardia is a common cause of undifferentiated supraventricular tachycardia. In patients with manifest or concealed accessory pathways, it is imperative to assess for the presence of other accessory pathways. Multiple accessory pathways are present in 4% to 10% of patients and are more common in patients with structural heart disease. In rare cases, multiple accessory pathways can act as the anterograde and retrograde limbs of the tachycardia.

  9. Retrograde Stent Placement for Coil Embolization of a Wide-Necked Posterior Inferior Cerebellar Artery Aneurysm

    PubMed Central

    Roh, Hong Gee; Choi, Jin Woo; Cho, Joon; Moon, Won-Jin; Solander, Sten

    2012-01-01

    Wide-necked aneurysms of the posterior inferior cerebellar artery (PICA) are infrequently encountered in cerebrovascular practice, and endovascular treatment is difficult or impossible even with the use of several neck remodeling techniques. We present the case of a patient with a wide-necked aneurysm of the PICA, which was treated by the retrograde stenting through the contralateral vertebral artery and vertebrobasilar junction with antegrade coil embolization. PMID:22778576

  10. Transmission of Salmonella enteritidis after endoscopic retrograde cholangiopancreatography because of inadequate endoscope decontamination.

    PubMed

    Robertson, Paul; Smith, Andrew; Anderson, Margaret; Stewart, Jackie; Hamilton, Kate; McNamee, Sandra; Curran, Evonne T

    2017-04-01

    We report a historic nosocomial outbreak of Salmonella enteritidis affecting 4 inpatients who underwent endoscopic retrograde cholangiopancreatography. The cause was attributed to inadequate decontamination of an on-loan endoscope used over a weekend. This report highlights the risks of using on-loan endoscopes, particularly regarding their commissioning and adherence to disinfection protocols. In an era of increasing antibiotic resistance, transmission of Enterobacteriaceae by endoscopes remains a significant concern.

  11. Retrograde Inversion Stripping as a Complication of the Clarivein® Mechanochemical Venous Ablation Procedure

    PubMed Central

    Moore, HM; Franklin, IJ; Davies, AH

    2015-01-01

    The endovenous revolution has accelerated the development of new techniques and devices for the treatment of varicose veins. The ClariVein® mechanochemical ablation device offers tumescentless treatment with a rotating ablation tip that can theoretically become stuck in tissue. We present the first report of retrograde stripping of the small saphenous vein without anaesthesia following attempted use of the ClariVein® device, without adverse sequelae. PMID:25723675

  12. Functional relationship between mTERF4 and GUN1 in retrograde signaling

    PubMed Central

    Sun, Xuwu; Xu, Duorong; Liu, Zhixin; Kleine, Tatjana; Leister, Dario

    2016-01-01

    Plastid-to-nucleus retrograde signaling plays an important role in regulating the expression of photosynthesis-associated nuclear genes (PhANGs) in accordance with physiological demands on chloroplast biogenesis and function. Despite its fundamental importance, little is known about the molecular nature of the plastid gene expression (PGE)-dependent type of retrograde signaling. PGE is a multifaceted process, and several factors, including pentatricopeptide repeat (PPR) proteins, are involved in its regulation. The PPR protein GUN1 plays a central role in PGE-dependent retrograde signaling. In this study, we isolated a mutant exhibiting up-regulation of CHLOROPHYLL A/B-BINDING PROTEIN (CAB) under normal growth conditions (named coe1 for CAB overexpression 1). The coe1 mutant has a single-base mutation in the gene for mitochondrial transcription termination factor 4 (mTERF4)/BSM/RUG2, which plays a role in regulating the processing of certain plastid transcripts. Defects in GUN1 or mTERF4 de-repressed the expression of specific plastid mRNAs in the presence of lincomycin (LIN). In wild-type plants, treatment with LIN or spectinomycin (SPE) inhibited processing of plastid transcripts. Comparative analysis revealed that in gun1 and coe1/mterf4, but not in wild-type, gun4, or gun5 plants, the processing of plastid transcripts and expression levels of Lhcb1 mRNA were affected in opposite ways when plants were grown in the presence of LIN or SPE. In addition, the coe1 mutation affected the intracellular accumulation and distribution of GUN1, as well as its plastid signaling activity. Taken together, these results suggest that GUN1 and COE1 cooperate in PGE and retrograde signaling. PMID:26685190

  13. Percutaneous Retrograde Sclerotherapy for Refractory Bleeding of Jejunal Varices: Direct Injection via Superficial Epigastric Vein

    SciTech Connect

    Nakata, Manabu Nakata, Waka; Isoda, Norio Yoshizawa, Mitsuyo; Sugimoto, Hideharu

    2012-02-15

    Small-bowel varices are rare and almost always occur in cases with portal hypertension. We encountered a patient with bleeding jejunal varices due to liver cirrhosis. Percutaneous retrograde sclerotherapy was performed via the superficial epigastric vein. Melena disappeared immediately after treatment. Disappearance of jejunal varices was confirmed by contrast-enhanced computed tomography. After 24 months of follow-up, no recurrent melena was observed.

  14. Role of Retrograde Trafficking in Stress Response, Host Cell Interactions, and Virulence of Candida albicans

    PubMed Central

    Liu, Yaoping; Solis, Norma V.; Heilmann, Clemens J.; Phan, Quynh T.; Mitchell, Aaron P.; Klis, Frans M.

    2014-01-01

    In Saccharomyces cerevisiae, the vacuolar protein sorting complexes Vps51/52/53/54 and Vps15/30/34/38 are essential for efficient endosome-to-Golgi complex retrograde transport. Here we investigated the function of Vps15 and Vps51, representative members of these complexes, in the stress resistance, host cell interactions, and virulence of Candida albicans. We found that C. albicans vps15Δ/Δ and vps51Δ/Δ mutants had abnormal vacuolar morphology, impaired retrograde protein trafficking, and dramatically increased susceptibility to a variety of stressors. These mutants also had reduced capacity to invade and damage oral epithelial cells in vitro and attenuated virulence in the mouse model of oropharyngeal candidiasis. Proteomic analysis of the cell wall of the vps51Δ/Δ mutant revealed increased levels of the Crh11 and Utr2 transglycosylases, which are targets of the calcineurin signaling pathway. The transcript levels of the calcineurin pathway members CHR11, UTR2, CRZ1, CNA1, and CNA2 were elevated in the vps15Δ/Δ and vps51Δ/Δ mutants. Furthermore, these strains were highly sensitive to the calcineurin-specific inhibitor FK506. Also, deletion of CHR11 and UTR2 further increased the stress susceptibility of these mutants. In contrast, overexpression of CRH11 and UTR2 partially rescued their defects in stress resistance, but not host cell interactions. Therefore, intact retrograde trafficking in C. albicans is essential for stress resistance, host cell interactions, and virulence. Aberrant retrograde trafficking stimulates the calcineurin signaling pathway, leading to the increased expression of Chr11 and Utr2, which enables C. albicans to withstand environmental stress. PMID:24363364

  15. Septic Complication After Balloon-Occluded Retrograde Transvenous Obliteration of Duodenal Variceal Bleeding

    SciTech Connect

    Akasaka, Thai; Shibata, Toshiya Isoda, Hiroyoshi; Taura, Kojiro; Arizono, Shigeki; Shimada, Kotaro; Togashi, Kaori

    2010-12-15

    We report a 64-year-old woman with duodenal varices who underwent balloon-occluded retrograde transvenous obliteration (B-RTO) complicated by intraprocedural variceal rupture. The patient developed shivering and a fever higher than 40{sup o}C 3 days after the B-RTO procedure. A blood culture grew Entereobacter cloacoe. This case represents a rare septic complication of B-RTO for duodenal varices.

  16. Anterolateral Popliteal Puncture Technique: A Novel Retrograde Approach for Chronic Femoropopliteal Occlusions.

    PubMed

    Tan, Michinao; Urasawa, Kazushi; Koshida, Ryoji; Haraguchi, Takuya; Kitani, Shunsuke; Igarashi, Yasumi; Sato, Katsuhiko

    2017-08-01

    To describe the feasibility and safety of an anterolateral popliteal puncture technique as a retrograde access to chronic total occlusions (CTOs) in the femoropopliteal segment. Twenty consecutive patients (mean age 75.1±10.9 years; 13 women) with symptomatic femoropopliteal occlusive disease underwent endovascular therapy via a retrograde access using the anterolateral popliteal puncture technique. With the patient supine, the P3 segment of the popliteal artery was accessed with a sheathless technique intended to provide minimally invasive access. Subsequent to a wire rendezvous technique in the CTO, the antegrade guidewire was advanced to the below-the-knee artery. Hemostasis across the P3 segment was secured with balloon inflation alone or combined with thrombin-blood patch (TBP) injection. Both the anterolateral popliteal puncture technique and subsequent revascularization were successful in all patients. Mean hemostasis time for balloon inflation only was 7.73±4.03 vs 4.78±0.78 minutes for balloon inflation with TBP injection. There were no in-hospital deaths or complications, including pseudoaneurysms, arteriovenous fistulas, hematomas, embolic complications, or nerve damage. The anterolateral popliteal puncture technique is useful as an alternative retrograde access vs a conventional transpopliteal approach for CTOs in the femoropopliteal segment if antegrade recanalization has failed. This technique may become one option for retrograde access in patients with severe below-the-knee lesions or with CTOs that extend to the P2 segment of the popliteal artery. Furthermore, this technique has the added benefit of allowing patients to remain in the supine position throughout treatment.

  17. [Dilatation of the common bile duct without visible obstruction at endoscopic retrograde cholangiography. Description and development].

    PubMed

    Seyrig, J A; Liguory, C; Buffet, C; Fabre, M; Fritsch, J; Choury, A; Ladouch-Badre, A; Liguory-Brunaud, M D; Etienne, J P

    1988-05-01

    The aim of this study was to specify the signs and course of patients with a dilated common bile duct without obstruction. We included patients with a dilated common bile duct of more than 12 mm on endoscopic retrograde cholangiography, and we excluded patients with stones, tumor or other visible obstruction. Two hundred and seven patients (8.4 p. 100 of endoscopic retrograde cholangiography) were included. One hundred and nineteen (57.5 p. 100) had undergone cholecystectomy. Sixty-five p. 100 of patients had signs suggesting biliary tract disease, and 78 p. 100 had biological signs of cholestasis. The size of the common bile duct was not different whether the patient had been cholecystectomized (16.2 +/- 0.3 mm.M +/- SEM) or not (16.2 +/- 0.4 mm). Forty-one patients in the non cholecystectomized group had gallbladder stones. Thus, 47 of our 207 patients (23 p. 100) had neither gallbladder stones nor previous cholecystectomy. Endoscopic retrograde cholangiography was completed by endoscopic sphincterotomy in 130 patients, either in the intent of not missing obstruction, or for therapeutic purposes. Follow-up more than one month after endoscopic retrograde cholangiography was available for 159 patients (77 p. 100). The median survival was 73 months. One hundred and ten patients (69 p. 100) were asymptomatic, 36 (23 p. 100) had atypical abdominal pain while 13 (8 p. 100) patients had episodes of biliary colic and/or fever and/or jaundice. During follow-up, an initially unrecognized obstacle was discovered in 8 patients: 5 common bile duct stones, 2 ampullary tumors and one pancreatic tumor.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. The movement of membranous organelles in axons. Electron microscopic identification of anterogradely and retrogradely transported organelles

    PubMed Central

    1980-01-01

    To identify the structures to be rapidly transported through the axons, we developed a new method to permit local cooling of mouse saphenous nerves in situ without exposing them. By this method, both anterograde and retrograde transport were successfully interrupted, while the structural integrity of the nerves was well preserved. Using radioactive tracers, anterogradely transported proteins were shown to accumulate just proximal to the cooled site, and retrogradely transported proteins just distal to the cooled site. Where the anterogradely transported proteins accumulated, the vesiculotubular membranous structures increased in amount inside both myelinated and unmyelinated axons. Such accumulated membranous structures showed a relatively uniform diameter of 50--80 nm, and some of them seemed to be continuous with the axonal smooth endoplasmic reticulum (SER). Thick sections of nerves selectively stained for the axonal membranous structures revealed that the network of the axonal SER was also packed inside axons proximal to the cooled site. In contrast, large membranous bodies of varying sizes accumulated inside axons just distal to the cooled site, where the retrogradely transported proteins accumulated. These bodies were composed mainly of multivesicular bodies and lamellated membranous structures. When horseradish peroxidase was administered in the distal end of the nerve, membranous bodies showing this activity accumulated, together with unstained membranous bodies. Hence, we are led to propose that, besides mitochondria, the membranous components in the axon can be classified into two systems from the viewpoint of axonal transport: "axonal SER and vesiculotubular structures" in the anterograde direction and "large membranous bodies" in the retrograde direction. PMID:6153657

  19. Retrograde Coronary Venous Ethanol Infusion for Ablation of Refractory Ventricular Tachycardia.

    PubMed

    Kreidieh, Bahij; Rodríguez-Mañero, Moisés; Schurmann, Paul; Ibarra-Cortez, Sergio Hugo; Dave, Amish S; Valderrábano, Miguel

    2016-07-01

    Radiofrequency ablation (RFA) of ventricular tachycardia (VT) can fail because of inaccessibility to the VT substrate. Transarterial coronary ethanol ablation can be effective but entails arterial instrumentation risk. We hypothesized that retrograde coronary venous ethanol ablation can be an alternative bail-out approach to failed VT RFA. Out of 334 consecutive patients undergoing VT/premature ventricular contraction ablation, 7 patients underwent retrograde coronary venous ethanol ablation. Six out of 7 patients had failed RFA attempts (including epicardial in 3). Coronary venogram-guided venous mapping was performed using a 4F quadripolar catheter or an alligator-clip-connected angioplasty wire. Targeted veins included those with early presystolic potentials and pace-maps matching VT/premature ventricular contraction. An angioplasty balloon (1.5-2×6 mm) was used to deliver 1 to 4 cc of 98% ethanol into a septal branch of the anterior interventricular vein in 5 patients with left ventricular summit VT, a septal branch of the middle cardiac vein, and a posterolateral coronary vein (n=1 each). The clinical VT was successfully ablated acutely in all patients. There were no complications of retrograde coronary venous ethanol ablation, but 1 patient developed pericardial and pleural effusion attributed to pericardial instrumentation. On follow-up of 590±722 days, VT recurred in 4 out of 7 patients, 3 of whom were successfully reablated with RFA. Retrograde coronary venous ethanol ablation is safe and feasible as a bail-out approach to failed VT RFA, particularly those originating from the left ventricular summit. © 2016 American Heart Association, Inc.

  20. Successful Treatment of Mesenteric Varices After Living Donor Liver Transplantation with Retrograde Transvenous Obliteration Via an Abdominal Wall Vein

    SciTech Connect

    Ikeda, Osamu Tamura, Yoshitaka; Nakasone, Yutaka; Yamashita, Yasuyuki; Okajima, Hideaki; Asonuma, Katsuhiro; Inomata, Yukihiro

    2010-06-15

    Balloon-occluded retrograde transvenous obliteration is an established treatment for gastric varices; it has been used more rarely to treat mesenteric varices. We report a 12-year-old girl who had received a living donor liver transplant and suffered melena due to ruptured mesenteric varices. We addressed treatment of the mesenteric varices by retrograde transvenous obliteration of an abdominal wall collateral vein detected by superior mesenteric arteriography.

  1. Acoustic determination of dewpoints in natural gas mixtures and retrograde condensates. Annual report, January 1-December 31, 1990

    SciTech Connect

    Colgate, S.O.

    1991-01-01

    In a continuation of verification studies of the acoustic resonance technique for phase boundary determinations, the critical point and some neighboring dewpoints and bubble points of a complex mixture, the recombined Hobart Ranch retrograde condensate, are to be measured and compared to earlier visual technique measurements (D.B. Robinson, et al.). A new high performance FFT-ARS spherical resonator assembly was designed, fabricated and tested. Measurements on the retrograde condensate system are ready to begin.

  2. Manipulation of arterial stiffness, wave reflections, and retrograde shear rate in the femoral artery using lower limb external compression.

    PubMed

    Heffernan, Kevin S; Lefferts, Wesley K; Kasprowicz, Ari G; Tarzia, Brendan J; Thijssen, Dick H; Brutsaert, Tom D

    2013-07-01

    Exposure of the arterial wall to retrograde shear acutely leads to endothelial dysfunction and chronically contributes to a proatherogenic vascular phenotype. Arterial stiffness and increased pressure from wave reflections are known arbiters of blood flow in the systemic circulation and each related to atherosclerosis. Using distal external compression of the calf to increase upstream retrograde shear in the superficial femoral artery (SFA), we examined the hypothesis that changes in retrograde shear are correlated with changes in SFA stiffness and pressure from wave reflections. For this purpose, a pneumatic cuff was applied to the calf and inflated to 0, 35, and 70 mmHg (5 min compression, randomized order, separated by 5 min) in 16 healthy young men (23 ± 1 years of age). Doppler ultrasound and wave intensity analysis was used to measure SFA retrograde shear rate, reflected pressure wave intensity (negative area [NA]), elastic modulus (Ep), and a single-point pulse wave velocity (PWV) during acute cuff inflation. Cuff inflation resulted in stepwise increases in retrograde shear rate (P < 0.05 for main effect). There were also significant cuff pressure-dependent increases in NA, Ep, and PWV across conditions (P < 0.05 for main effects). Change in NA, but not Ep or PWV, was associated with change in retrograde shear rate across conditions (P < 0.05). In conclusion, external compression of the calf increases retrograde shear, arterial stiffness, and pressure from wave reflection in the upstream SFA in a dose-dependent manner. Wave reflection intensity, but not arterial stiffness, is correlated with changes in peripheral retrograde shear with this hemodynamic manipulation.

  3. Multiple-indicator dilution technique for characterization of normal and retrograde flow in once-through rat liver perfusions

    SciTech Connect

    St-Pierre, M.V.; Schwab, A.J.; Goresky, C.A.; Lee, W.F.; Pang, K.S.

    1989-02-01

    The technique of normal and retrograde rat liver perfusion has been widely used to probe zonal differences in drug-metabolizing activities. The validity of this approach mandates the same tissue spaces being accessed by substrates during both normal and retrograde perfusions. Using the multiple-indicator dilution technique, we presently examine the extent to which retrograde perfusion alters the spaces accessible to noneliminated references. A bolus dose of 51Cr-labeled red blood cells, 125I-albumin, 14C-sucrose and 3H2O was injected into the portal (normal) or hepatic (retrograde) vein of rat livers perfused at 10 ml per min per liver. The outflow perfusate was serially collected over 220 sec to characterize the transit times and the distribution spaces of the labels. During retrograde perfusion, red blood cells, albumin and sucrose profiles peaked later and lower than during normal perfusion, whereas the water curves were similar. The transit times of red blood cells, albumin and sucrose were longer (p less than 0.005), whereas those for water did not change. Consequently, retrograde flow resulted in significantly larger sinusoidal blood volumes (45%), albumin Disse space (42%) and sucrose Disse space (25%) than during normal flow, whereas the distribution spaces for total and intracellular water remained unaltered. The distension of the vascular tree was confirmed by electron microscopy, by which occasional isolated foci of widened intercellular recesses and spaces of Disse were observed. Cellular ultrastructure was otherwise unchanged, and there was no difference found between normal and retrograde perfusion for bile flow rates, AST release, perfusion pressure, oxygen consumption and metabolic removal of ethanol, a substrate with flow-limited distribution, which equilibrates rapidly with cell water (hepatic extraction ratios were virtually identical: normal vs. retrograde, 0.50 vs. 0.48 at 6 to 7.4 mM input concentration).

  4. Retrograde and anterograde memory following selective damage to the dorsolateral entorhinal cortex.

    PubMed

    Gervais, Nicole J; Barrett-Bernstein, Meagan; Sutherland, Robert J; Mumby, Dave G

    2014-12-01

    Anatomical and electrophysiological evidence suggest the dorsolateral entorhinal cortex (DLEC) is involved in processing spatial information, but there is currently no consensus on whether its functions are necessary for normal spatial learning and memory. The present study examined the effects of excitotoxic lesions of the DLEC on retrograde and anterograde memory on two tests of allocentric spatial learning: a hidden fixed-platform watermaze task, and a novelty-preference-based dry-maze test. Deficits were observed on both tests when training occurred prior to but not following n-methyl d-aspartate (NMDA) lesions of DLEC, suggesting retrograde memory impairment in the absence of anterograde impairments for the same information. The retrograde memory impairments were temporally-graded; rats that received DLEC lesions 1-3 days following training displayed deficits, while those that received lesions 7-10 days following training performed like a control group that received sham surgery. The deficits were not attenuated by co-infusion of tetrodotoxin, suggesting they are not due to disruption of neural processing in structures efferent to the DLEC, such as the hippocampus. The present findings provide evidence that the DLEC is involved in the consolidation of allocentric spatial information.

  5. Apicoectomies with the erbium laser: a complementary technique for retrograde endodontic treatment.

    PubMed

    Angiero, Francesca; Benedicenti, Stefano; Signore, Antonio; Parker, Steven; Crippa, Rolando

    2011-12-01

    The purpose of this study was to evaluate the efficacy of erbium lasers for retrograde endodontic treatment, in terms of clinical outcome and therapeutic success. Apicoectomy with retrograde filling is a well-established surgical procedure to treat teeth affected by persistent periapical lesions. The apical root end is generally removed with burs, and the adjacent periapical tissue curetted, or alternatively treated with ultrasound or laser. Between 2000 and 2010, 65 apicoectomies were performed on necrotic teeth that presented apical lesions (29 men, 36 women). The lasers used in the study were the erbium:yttrium-aluminum-garnet (Er:YAG) laser, wavelength 2940 nm, and the erbium,chromium-doped:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser, wavelength 2780 nm. Of the 65 teeth in the study, failure only occurred in 9 CASES, MANIFESTING AFTER DIFFERENT TIMES. THE REMAINING PATIENTS, 86.15%, experienced no complications, and their treatment followed a positive course. Laser-assisted surgery increases the range of therapeutic approaches in the sphere of retrograde endodontic treatment. The results of this study show that the erbium laser, used for apicoectomy, results in a high success rate with considerable benefit in terms of clinical outcome and therapeutic success.

  6. Retrograde axonal transport of VZV: kinetic studies in hESC-derived neurons.

    PubMed

    Grigoryan, Sergei; Kinchington, Paul R; Yang, In Hong; Selariu, Anca; Zhu, Hua; Yee, Michael; Goldstein, Ronald S

    2012-12-01

    Retrograde axonal transport of the neurotropic alphaherpesvirus Varicella zoster virus (VZV) from vesicles at the skin results in sensory neuron infection and establishment of latency. Reactivation from latency leads to painful herpes zoster. The lack of a suitable animal model of these processes for the highly human-restricted VZV has resulted in a dearth of knowledge regarding the axonal transport of VZV. We recently demonstrated VZV infection of distal axons, leading to subsequent capsid transport to the neuronal somata, and replication and release of infectious virus using a new model based on neurons derived from human embryonic stem cells (hESC). In the present study, we perform a kinetic analysis of the retrograde transport of green fluorescent protein-tagged ORF23 in VZV capsids using hESC-derived neurons compartmentalized microfluidic chambers and time-lapse video microscopy. The motion of the VZV was discontinuous, showing net retrograde movement with numerous short pauses and reversals in direction. Velocities measured were higher 1 h after infection than 6 h after infection, while run lengths were similar at both time points. The hESC-derived neuron model was also used to show that reduced neuronal spread by a VZV loss-of-function mutant for ORF7 is not due to the prevention of axonal infection and transport of the virus to the neuronal somata. hESC-derived neurons are, therefore, a powerful model for studying axonal transport of VZV and molecular characteristics of neuronal infection.

  7. WD60/FAP163 is a dynein intermediate chain required for retrograde intraflagellar transport in cilia.

    PubMed

    Patel-King, Ramila S; Gilberti, Renée M; Hom, Erik F Y; King, Stephen M

    2013-09-01

    Retrograde intraflagellar transport (IFT) is required for assembly of cilia. We identify a Chlamydomonas flagellar protein (flagellar-associated protein 163 [FAP163]) as being closely related to the D1bIC(FAP133) intermediate chain (IC) of the dynein that powers this movement. Biochemical analysis revealed that FAP163 is present in the flagellar matrix and is actively trafficked by IFT. Furthermore, FAP163 copurified with D1bIC(FAP133) and the LC8 dynein light chain, indicating that it is an integral component of the retrograde IFT dynein. To assess the functional role of FAP163, we generated an RNA interference knockdown of the orthologous protein (WD60) in planaria. The Smed-wd60(RNAi) animals had a severe ciliary assembly defect that dramatically compromised whole-organism motility. Most cilia were present as short stubs that had accumulated large quantities of IFT particle-like material between the doublet microtubules and the membrane. The few remaining approximately full-length cilia had a chaotic beat with a frequency reduced from 24 to ∼10 Hz. Thus WD60/FAP163 is a dynein IC that is absolutely required for retrograde IFT and ciliary assembly.

  8. Retrograde Lymph Flow Leads to Chylothorax in Transgenic Mice with Lymphatic Malformations.

    PubMed

    Nitschké, Maximilian; Bell, Alexander; Karaman, Sinem; Amouzgar, Meelad; Rutkowski, Joseph M; Scherer, Philipp E; Alitalo, Kari; McDonald, Donald M

    2017-09-01

    Chylous pleural effusion (chylothorax) frequently accompanies lymphatic vessel malformations and other conditions with lymphatic defects. Although retrograde flow of chyle from the thoracic duct is considered a potential mechanism underlying chylothorax in patients and mouse models, the path chyle takes to reach the thoracic cavity is unclear. Herein, we use a novel transgenic mouse model, where doxycycline-induced overexpression of vascular endothelial growth factor (VEGF)-C was driven by the adipocyte-specific promoter adiponectin (ADN), to determine how chylothorax forms. Surprisingly, 100% of adult ADN-VEGF-C mice developed chylothorax within 7 days. Rapid, consistent appearance of chylothorax enabled us to examine the step-by-step development in otherwise normal adult mice. Dynamic imaging with a fluorescent tracer revealed that lymph in the thoracic duct of these mice could enter the thoracic cavity by retrograde flow into enlarged paravertebral lymphatics and subpleural lymphatic plexuses that had incompetent lymphatic valves. Pleural mesothelium overlying the lymphatic plexuses underwent exfoliation that increased during doxycycline exposure. Together, the findings indicate that chylothorax in ADN-VEGF-C mice results from retrograde flow of chyle from the thoracic duct into lymphatic tributaries with defective valves. Chyle extravasates from these plexuses and enters the thoracic cavity through exfoliated regions of the pleural mesothelium. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  9. Mozart, Mozart Rhythm and Retrograde Mozart Effects: Evidences from Behaviours and Neurobiology Bases

    PubMed Central

    Xing, Yingshou; Xia, Yang; Kendrick, Keith; Liu, Xiuxiu; Wang, Maosen; Wu, Dan; Yang, Hua; Jing, Wei; Guo, Daqing; Yao, Dezhong

    2016-01-01

    The phenomenal finding that listening to Mozart K.448 enhances performance on spatial tasks has motivated a continuous surge in promoting music education over the past two decades. But there have been inconsistent reports in previous studies of the Mozart effect. Here conducted was a systematic study, with Mozart and retrograde Mozart music, Mozart music rhythm and pitch, behaviours and neurobiology tests, rats and humans subjects. We show that while the Mozart K.448 has positive cognitive effects, the retrograde version has a negative effect on rats’ performance in the Morris water maze test and on human subjects’ performance in the paper folding and cutting test and the pencil-and-paper maze test. Such findings are further confirmed by subsequent immunohistochemical analyses in rats on the neurogenesis and protein levels of BDNF and its receptor, TrkB. Furthermore, when the rhythm and pitch of the normal and retrograde Mozart music are manipulated independently, the learning performance of the rats in the Morris water maze test indicated that rhythm is a crucial element in producing the behavioural effects. These findings suggest that the nature of Mozart effect is the Mozart rhythm effect, and indicate that different music may have quite different to opposite effects. Further study on rhythm effect may provide clues to understand the common basis over animals from rats to humans. PMID:26795072

  10. Mozart, Mozart Rhythm and Retrograde Mozart Effects: Evidences from Behaviours and Neurobiology Bases.

    PubMed

    Xing, Yingshou; Xia, Yang; Kendrick, Keith; Liu, Xiuxiu; Wang, Maosen; Wu, Dan; Yang, Hua; Jing, Wei; Guo, Daqing; Yao, Dezhong

    2016-01-21

    The phenomenal finding that listening to Mozart K.448 enhances performance on spatial tasks has motivated a continuous surge in promoting music education over the past two decades. But there have been inconsistent reports in previous studies of the Mozart effect. Here conducted was a systematic study, with Mozart and retrograde Mozart music, Mozart music rhythm and pitch, behaviours and neurobiology tests, rats and humans subjects. We show that while the Mozart K.448 has positive cognitive effects, the retrograde version has a negative effect on rats' performance in the Morris water maze test and on human subjects' performance in the paper folding and cutting test and the pencil-and-paper maze test. Such findings are further confirmed by subsequent immunohistochemical analyses in rats on the neurogenesis and protein levels of BDNF and its receptor, TrkB. Furthermore, when the rhythm and pitch of the normal and retrograde Mozart music are manipulated independently, the learning performance of the rats in the Morris water maze test indicated that rhythm is a crucial element in producing the behavioural effects. These findings suggest that the nature of Mozart effect is the Mozart rhythm effect, and indicate that different music may have quite different to opposite effects. Further study on rhythm effect may provide clues to understand the common basis over animals from rats to humans.

  11. The sealing ability of novel Kryptonite adhesive bone cement as a retrograde filling material

    PubMed Central

    Uzun, İsmail; Keskin, Cangül; Güler, Buğra

    2016-01-01

    Background. This study evaluated the ability of Kryptonite bone cement in sealing retrograde cavities. Methods. The root canals of one hundred extracted human maxillary incisor teeth were instrumented up to master apical file #40 using Mtwo rotary system and obturated with gutta-percha and AHPlus sealer by cold lateral compaction method. The specimens were assigned to one control group and four experimental groups based on the retrograde filling materials (n=20). The specimens were immersed in 0.5% Rhodamine B solution for 48h. Then the specimens were divided longitudinally into two parts and the depth of dye penetration was assessed under ×10 magnification. Data were analyzed using one-way ANOVA and Bonferroni tests. Results. There were statistically significant difference between the experimental groups and the control group (P<0.05). There were no statistically significant differences between the experimental groups in dye penetration scores (P>0.05). Conclusion. Kryptonite cement provided optimal apical seal in a manner similar to MTA, amalgam and IRM when used as a retrograde filling cement. PMID:27651886

  12. Innovations in the Endovascular Management of Critical Limb Ischemia: Retrograde Tibiopedal Access and Advanced Percutaneous Techniques.

    PubMed

    Mustapha, Jihad A; Diaz-Sandoval, Larry J; Saab, Fadi

    2017-08-01

    Retrograde tibiopedal access and interventions have contributed to advance of endovascular techniques to treat critical limb ischemia (CLI) patients. This review encompasses the spectrum from advanced diagnostic imaging and technical therapeutic approaches for infrapopliteal occlusions, to a discussion of current standards and future directions. Contemporary studies of infrapopliteal angioplasty show suboptimal short-term and 1-year clinical outcomes. Comparative data is needed to shift the focus from PTA to disruptive treatment modalities that can further improve outcomes. Retrograde pedal access has emerged as an important tool to facilitate successfully percutaneous revascularization and limb salvage in patients with CLI. To efficiently approach the complexity of CLI, new thought processes are needed to change the reigning paradigms. Retrograde tibial-pedal access has shown improvement in the rate of successful revascularizations and is an important tool in the amputation-prevention armamentarium. Additional technologies may further improve success rates. Drug-eluting stents have shown better outcomes than PTA in patients with focal infrapopliteal lesions. Registry data have demonstrated the advantage of several atherectomy devices in the tibial arteries. More recently, bioresorbable vascular scaffolds have been used successfully, and further studies with drug-coated balloons are underway. Interventional operators are now even working in the inframalleolar space to reconstitute the plantar arch. Well-conducted studies are needed to generate high-quality evidence in the field of critical limb ischemia management.

  13. Unraveling retrograde signaling pathways: finding candidate signaling molecules via metabolomics and systems biology driven approaches.

    PubMed

    Caldana, Camila; Fernie, Alisdair R; Willmitzer, Lothar; Steinhauser, Dirk

    2012-01-01

    A tight coordination of biological processes between cellular compartments and organelles is crucial for the survival of any eukaryotic organism. According to cellular requirements, signals can be generated within organelles, such as chloroplasts and mitochondria, modulating the nuclear gene expression in a process called retrograde signaling. Whilst many research efforts have been focused on dissecting retrograde signaling pathways using biochemical and genetics approaches, metabolomics and systems biology driven studies have illustrated their great potential for hypotheses generation and for dissecting signaling networks in a rather unbiased or untargeted fashion. Recently, integrative genomics approaches, in which correlation analysis has been applied on transcript and metabolite profiling data of Arabidopsis thaliana, revealed the identification of metabolites which are putatively acting as mediators of nuclear gene expression. Complimentary, the continuous technological developments in the field of metabolomics per se has further demonstrated its potential as a very suitable readout to unravel metabolite-mediated signaling processes. As foundation for these studies here we outline and discuss recent advances in elucidating retrograde signaling molecules and pathways with an emphasis on metabolomics and systems biology driven approaches.

  14. Geldanamycin Enhances Retrograde Transport of Shiga Toxin in HEp-2 Cells.

    PubMed

    Dyve Lingelem, Anne Berit; Hjelseth, Ieva Ailte; Simm, Roger; Torgersen, Maria Lyngaas; Sandvig, Kirsten

    2015-01-01

    The heat shock protein 90 (Hsp90) inhibitor geldanamycin (GA) has been shown to alter endosomal sorting, diverting cargo destined for the recycling pathway into the lysosomal pathway. Here we investigated whether GA also affects the sorting of cargo into the retrograde pathway from endosomes to the Golgi apparatus. As a model cargo we used the bacterial toxin Shiga toxin, which exploits the retrograde pathway as an entry route to the cytosol. Indeed, GA treatment of HEp-2 cells strongly increased the Shiga toxin transport to the Golgi apparatus. The enhanced Golgi transport was not due to increased endocytic uptake of the toxin or perturbed recycling, suggesting that GA selectively enhances endosomal sorting into the retrograde pathway. Moreover, GA activated p38 and both inhibitors of p38 or its substrate MK2 partially counteracted the GA-induced increase in Shiga toxin transport. Thus, our data suggest that GA-induced p38 and MK2 activation participate in the increased Shiga toxin transport to the Golgi apparatus.

  15. Flexible robotic retrograde renoscopy: description of novel robotic device and preliminary laboratory experience.

    PubMed

    Desai, Mihir M; Aron, Monish; Gill, Inderbir S; Pascal-Haber, Georges; Ukimura, Osamu; Kaouk, Jihad H; Stahler, Gregory; Barbagli, Federico; Carlson, Christopher; Moll, Fredric

    2008-07-01

    To describe a novel flexible robotic system for performing retrograde intrarenal surgery. Remote robotic flexible ureterorenoscopy was performed bilaterally in 5 acute swine (10 kidneys). A novel 14F robotic catheter system, which manipulated a passive optical fiberscope mounted on a remote catheter manipulator was used. The technical feasibility, efficiency, and reproducibility of accessing all calices were assessed. Additionally, laser lithotripsy of calculi and laser ablation of renal papillae were performed. The robotic catheter system could be introduced de novo in eight ureters; two ureters required balloon dilation. The ureteroscope could be successfully manipulated remotely into 83 (98%) of the 85 calices. The time required to inspect all calices within a given kidney decreased with experience from 15 minutes in the first kidney to 49 seconds in the last (mean 4.6 minutes). On a visual analog scale (1, worst to 10, best), the reproducibility of caliceal access was rated at 8, and instrument tip stability was rated at 10. A renal pelvic perforation constituted the solitary complication. Histologic examination of the ureter showed changes consistent with acute dilation without areas of necrosis. A novel robotic catheter system is described for performing retrograde ureterorenoscopy. The potential advantages compared with conventional manual flexible ureterorenoscopy include an increased range of motion, instrument stability, and improved ergonomics. Ongoing refinement is likely to expand the role of this technology in retrograde intrarenal surgery in the near future.

  16. Percutaneous balloon aortic valvuloplasty: antegrade transseptal vs. conventional retrograde transarterial approach.

    PubMed

    Sakata, Yoshihito; Syed, Zubair; Salinger, Michael H; Feldman, Ted

    2005-03-01

    Percutaneous balloon aortic valvuloplasty (BAV) has been limited predominantly to a palliative treatment for poor surgical candidates with critical aortic stenosis and multiple high-risk or comorbid conditions. The most commonly used technique for BAV is the retrograde approach, in which the balloon is passed via the femoral artery using 12-14 Fr sheaths. We compared an antegrade transseptal approach using the Inoue balloon vs. the retrograde transarterial approach using conventional balloons. The antegrade group had an improved acute hemodynamic outcome, including 20% additional increase of aortic valve area and 20% greater reduction of transaortic valve gradient compared to the retrograde approach. Preclosure with the Perclose device was used for the 14 Fr venous access sites, resulting in immediate hemostasis, minimizing the need for transfusion, and diminishing the period of bed rest. The improved acute efficacy and relative ease of venous access for the antegrade approach facilitate BAV by eliminating the need for large-caliber arterial access sheaths. The antegrade approach also incorporates technical elements necessary for percutaneous aortic valve replacement and may have expanded applications as an adjunct to this developing therapy. The impact of improved acute results on the long-term clinical outcome for this patient group will require further study.

  17. NUMERICAL SIMULATIONS OF NATURALLY TILTED, RETROGRADELY PRECESSING, NODAL SUPERHUMPING ACCRETION DISKS

    SciTech Connect

    Montgomery, M. M.

    2012-02-15

    Accretion disks around black hole, neutron star, and white dwarf systems are thought to sometimes tilt, retrogradely precess, and produce hump-shaped modulations in light curves that have a period shorter than the orbital period. Although artificially rotating numerically simulated accretion disks out of the orbital plane and around the line of nodes generate these short-period superhumps and retrograde precession of the disk, no numerical code to date has been shown to produce a disk tilt naturally. In this work, we report the first naturally tilted disk in non-magnetic cataclysmic variables using three-dimensional smoothed particle hydrodynamics. Our simulations show that after many hundreds of orbital periods, the disk has tilted on its own and this disk tilt is without the aid of radiation sources or magnetic fields. As the system orbits, the accretion stream strikes the bright spot (which is on the rim of the tilted disk) and flows over and under the disk on different flow paths. These different flow paths suggest the lift force as a source to disk tilt. Our results confirm the disk shape, disk structure, and negative superhump period and support the source to disk tilt, source to retrograde precession, and location associated with X-ray and He II emission from the disk as suggested in previous works. Our results identify the fundamental negative superhump frequency as the indicator of disk tilt around the line of nodes.

  18. Retrograde intramedullary fixation of long bone fractures through ipsilateral traumatic amputation sites.

    PubMed

    Wagner, Scott C; Chi, Benjamin B; Gordon, Wade T; Potter, Benjamin K

    2015-06-01

    The technique of retrograde intramedullary fixation of fractures through open traumatic amputations has not been previously described. We performed a retrospective case series at a tertiary-care military hospital setting. Ten patients met inclusion criteria. All were male, and all were injured through improvised explosive device. Outcome measures included the incidence of fracture nonunion, osteomyelitis or acute infection, heterotopic ossification (HO), as well as successful prosthesis fitting and ambulation. Average time to fixation after injury and amputation closure was 11.7 and 12.2 days, respectively. Follow-up averaged 20.2 months. The radiographic union rate was 100%, and time to osseous union averaged 7.5 months. One patient had an amputation site infection requiring revision, but none of the nails was removed for infectious reasons. HO occurred in 7 patients, and 2 patients required revision for symptomatic HO. All patients were successfully fitted with prostheses and able to ambulate. To our knowledge, this is the only series in the literature to specifically describe retrograde intramedullary fixation of long bone fractures through the zone of traumatic amputation sites. The infectious risk is relatively low, whereas the union rate (100%) and successful prosthesis fitting are high. For patients with similar injuries, retrograde intramedullary fixation through the zone of amputation is a viable treatment option.

  19. Subintimal Recanalization of Long Superficial Femoral Artery Occlusions Through the Retrograde Popliteal Approach

    SciTech Connect

    Yilmaz, Saim; Sindel, Timur; Ceken, Kagan; Alimoglu, Emel; Lueleci, Ersin

    2001-05-15

    Purpose: To investigate the value of the retrograde popliteal artery approach for the percutaneous intentional extraluminal recanalization (PIER) of long superficial femoral artery (SFA) occlusions.Methods: During a period of 17 months, PIER through ultrasound-guided retrograde popliteal artery puncture was performed for 39 long SFA occlusions in 37 patients. In six patients, six additional iliac artery stenoses were also treated via the popliteal approach.Results: The procedure was technically successful in 32 (82%) of 39 SFA occlusions; in 29, lesions were treated with balloon angioplasty alone, and in three, stents were also used. Cumulative patency rate was 66% at 6 months, 62% at 1 year, and 59% at 18 months. Additional iliac artery stenoses were successfully treated in the same session. Complications included two minor hematomas and two SFA ruptures, which required no treatment.Conclusion: PIER through retrograde popliteal puncture is a safe and effective method in the treatment of long femoropopliteal occlusions, with a high technical success, low complication rate and a reasonable short-term patency rate. The technique offers an alternative in cases where standard PIER is unsuccessful or contraindicated.

  20. Rabies virus envelope glycoprotein targets lentiviral vectors to the axonal retrograde pathway in motor neurons.

    PubMed

    Hislop, James N; Islam, Tarin A; Eleftheriadou, Ioanna; Carpentier, David C J; Trabalza, Antonio; Parkinson, Michael; Schiavo, Giampietro; Mazarakis, Nicholas D

    2014-06-06

    Rabies pseudotyped lentiviral vectors have great potential in gene therapy, not least because of their ability to transduce neurons following their distal axonal application. However, very little is known about the molecular processes that underlie their retrograde transport and cell transduction. Using multiple labeling techniques and confocal microscopy, we demonstrated that pseudotyping with rabies virus envelope glycoprotein (RV-G) enabled the axonal retrograde transport of two distinct subtypes of lentiviral vector in motor neuron cultures. Analysis of this process revealed that these vectors trafficked through Rab5-positive endosomes and accumulated within a non-acidic Rab7 compartment. RV-G pseudotyped vectors were co-transported with both the tetanus neurotoxin-binding fragment and the membrane proteins thought to mediate rabies virus endocytosis (neural cell adhesion molecule, nicotinic acetylcholine receptor, and p75 neurotrophin receptor), thus demonstrating that pseudotyping with RV-G targets lentiviral vectors for transport along the same pathway exploited by several toxins and viruses. Using motor neurons cultured in compartmentalized chambers, we demonstrated that axonal retrograde transport of these vectors was rapid and efficient; however, it was not able to transduce the targeted neurons efficiently, suggesting that impairment in processes occurring after arrival of the viral vector in the soma is responsible for the low transduction efficiency seen in vivo, which suggests a novel area for improvement of gene therapy vectors.

  1. AGAP2 regulates retrograde transport between early endosomes and the TGN

    PubMed Central

    Shiba, Yoko; Römer, Winfried; Mardones, Gonzalo A.; Burgos, Patricia V.; Lamaze, Christophe; Johannes, Ludger

    2010-01-01

    The retrograde transport route links early endosomes and the TGN. Several endogenous and exogenous cargo proteins use this pathway, one of which is the well-explored bacterial Shiga toxin. ADP-ribosylation factors (Arfs) are ~20 kDa GTP-binding proteins that are required for protein traffic at the level of the Golgi complex and early endosomes. In this study, we expressed mutants and protein fragments that bind to Arf-GTP to show that Arf1, but not Arf6 is required for transport of Shiga toxin from early endosomes to the TGN. We depleted six Arf1-specific ARF-GTPase-activating proteins and identified AGAP2 as a crucial regulator of retrograde transport for Shiga toxin, cholera toxin and the endogenous proteins TGN46 and mannose 6-phosphate receptor. In AGAP2-depleted cells, Shiga toxin accumulates in transferrin-receptor-positive early endosomes, suggesting that AGAP2 functions in the very early steps of retrograde sorting. A number of other intracellular trafficking pathways are not affected under these conditions. These results establish that Arf1 and AGAP2 have key trafficking functions at the interface between early endosomes and the TGN. PMID:20551179

  2. Acetylated adipate of retrograded starch as RS 3/4 type resistant starch.

    PubMed

    Kapelko-Żeberska, M; Zięba, T; Spychaj, R; Gryszkin, A

    2015-12-01

    This study was aimed at producing acetylated adipate of retrograded starch (ADA-R) with various degrees of substitution with functional groups and at determining the effect of esterification degree on resistance and pasting characteristics of the produced preparations. Paste was prepared from native potato starch, and afterwards frozen and defrosted. After drying and disintegration, the paste was acetylated and crosslinked using various doses of reagents. An increase in the total degree of esterification of the produced ADA-R-preparation caused an increase in its resistance to the action of amyloglucosidase. Viscosity of the paste produced from ADA-R-preparation in a wide range of acetylation degrees was increasing along with increasing crosslinking of starch. The study demonstrated that acetylated adipate of retrograded starch may be classified as a preparation of RS 3/4 type resistant starch (retrograded starch/chemically-modified starch) with good texture-forming properties. The conducted modification offers the possibility of modeling the level of resistance of the produced preparation.

  3. Measures of patient radiation exposure during endoscopic retrograde cholangiography: Beyond fluoroscopy time

    PubMed Central

    Kachaamy, Toufic; Harrison, Edwyn; Pannala, Rahul; Pavlicek, William; Crowell, Michael D; Faigel, Douglas O

    2015-01-01

    AIM: To determine whether fluoroscope time is a good predictor of patient radiation exposure during endoscopic retrograde cholangiopancreatography. METHODS: This is a prospective observational study of consecutive patients undergoing endoscopic retrograde cholangiopancreatography in a tertiary care setting. Data related to radiation exposure were collected. The following measures were obtained: Fluoroscopy time (FT), dose area product (DAP) and dose at reference point (DOSERP). Coefficients of determination were calculated to analyze the correlation between FT, DAP and DOSRP. Agreement between FT and DAP/DOSRP was assessed using Bland Altman plots. RESULTS: Four hundred sixty-three data sets were obtained. Fluoroscopy time average was 7.3 min. Fluoroscopy related radiation accounted for 86% of the total DAP while acquisition films related radiation accounted for 14% of the DAP. For any given FT there are wide ranges of DAP and DOSERP and the variability in both increases as fluoroscopy time increases. The coefficient of determination (R2) on the non transformed data for DAP and DOSERP versus FT were respectively 0.416 and 0.554. While fluoroscopy use was the largest contributor to patient radiation exposure during endoscopic retrograde cholangiography (ERCP), there is a wide variability in DAP and DOSERP that is not accounted for by FT. DAP and DOSERP increase in variability as FT increases. This translates into poor accuracy of FT in predicting DAP and DOSERP at higher radiation doses. CONCLUSION: DAP and DOSERP in addition to FT should be adopted as new ERCP quality measures to estimate patient radiation exposure. PMID:25684958

  4. WD60/FAP163 is a dynein intermediate chain required for retrograde intraflagellar transport in cilia

    PubMed Central

    Patel-King, Ramila S.; Gilberti, Renée M.; Hom, Erik F. Y.; King, Stephen M.

    2013-01-01

    Retrograde intraflagellar transport (IFT) is required for assembly of cilia. We identify a Chlamydomonas flagellar protein (flagellar-associated protein 163 [FAP163]) as being closely related to the D1bIC(FAP133) intermediate chain (IC) of the dynein that powers this movement. Biochemical analysis revealed that FAP163 is present in the flagellar matrix and is actively trafficked by IFT. Furthermore, FAP163 copurified with D1bIC(FAP133) and the LC8 dynein light chain, indicating that it is an integral component of the retrograde IFT dynein. To assess the functional role of FAP163, we generated an RNA interference knockdown of the orthologous protein (WD60) in planaria. The Smed-wd60(RNAi) animals had a severe ciliary assembly defect that dramatically compromised whole-organism motility. Most cilia were present as short stubs that had accumulated large quantities of IFT particle–like material between the doublet microtubules and the membrane. The few remaining approximately full-length cilia had a chaotic beat with a frequency reduced from 24 to ∼10 Hz. Thus WD60/FAP163 is a dynein IC that is absolutely required for retrograde IFT and ciliary assembly. PMID:23864713

  5. Quantification of tibial bone loss in antegrade versus retrograde tunnel placement for anterior cruciate ligament reconstruction.

    PubMed

    Osti, Michael; Krawinkel, Alessa; Hoffelner, Thomas; Benedetto, Karl Peter

    2015-08-01

    Tibial bone destruction during primary graft tunnel placement and tibial bone loss following tunnel enlargement represent major challenges in revision reconstruction of the anterior cruciate ligament (ACL). Initial all-inside ACL reconstruction facilitates the preparation of tibial bone sockets rather than full tunnels that potentially preserve tibial bone stock. The purpose of this study was to comparatively assess length, diameter and volume of tibial graft tunnels following all-inside and conventional ACL reconstruction. Postoperative computed tomography (CT) scans of 59 patients were assessed following ACL reconstruction. In 35 patients we used conventional antegrade tibial tunnel drilling and in 24 all-inside retrograde tibial bone sockets. Imaging analysis included total, minimal and maximal tunnel length and tunnel diameter. Tunnel volumes were calculated corresponding to these parameters. Statistically significant group differences (p < 0.01) could be detected for tibial tunnel volume, length and diameter between conventional antegrade and all-inside retrograde tibial bone tunnels and sockets, respectively. Compared with conventional techniques, all-inside retrograde drilling of tibial bone sockets is effective in preserving significant bone stock, which might be beneficial for revision reconstruction in cases of eventual primary graft failure.

  6. The GTPase IFT27 is involved in both anterograde and retrograde intraflagellar transport.

    PubMed

    Huet, Diego; Blisnick, Thierry; Perrot, Sylvie; Bastin, Philippe

    2014-04-24

    The construction of cilia and flagella depends on intraflagellar transport (IFT), the bidirectional movement of two protein complexes (IFT-A and IFT-B) driven by specific kinesin and dynein motors. IFT-B and kinesin are associated to anterograde transport whereas IFT-A and dynein participate to retrograde transport. Surprisingly, the small GTPase IFT27, a member of the IFT-B complex, turns out to be essential for retrograde cargo transport in Trypanosoma brucei. We reveal that this is due to failure to import both the IFT-A complex and the IFT dynein into the flagellar compartment. To get further molecular insight about the role of IFT27, GDP- or GTP-locked versions were expressed in presence or absence of endogenous IFT27. The GDP-locked version is unable to enter the flagellum and to interact with other IFT-B proteins and its sole expression prevents flagellum formation. These findings demonstrate that a GTPase-competent IFT27 is required for association to the IFT complex and that IFT27 plays a role in the cargo loading of the retrograde transport machinery.DOI: http://dx.doi.org/10.7554/eLife.02419.001.

  7. Intrastriatally Infused Exogenous CDNF Is Endocytosed and Retrogradely Transported to Substantia Nigra

    PubMed Central

    Vihinen, Helena; Bienemann, Ali; Palgi, Jaan; Voutilainen, Merja H.; Booms, Sigrid; Arumäe, Urmas

    2017-01-01

    Abstract Cerebral dopamine neurotrophic factor (CDNF) protects the nigrostriatal dopaminergic (DA) neurons in rodent models of Parkinson’s disease and restores DA circuitry when delivered after these neurons have begun to degenerate. These DA neurons have been suggested to transport striatal CDNF retrogradely to the substantia nigra (SN). However, in cultured cells the binding and internalization of extracellular CDNF has not been reported. The first aim of this study was to examine the cellular localization and pharmacokinetic properties of recombinant human CDNF (rhCDNF) protein after its infusion into rat brain parenchyma. Second, we aimed to study whether the transport of rhCDNF from the striatum to the SN results from its retrograde transport via DA neurons or from its anterograde transport via striatal GABAergic projection neurons. We show that after intrastriatal infusion, rhCDNF diffuses rapidly and broadly, and is cleared with a half-life of 5.5 h. Confocal microscopy analysis of brain sections at 2 and 6 h after infusion of rhCDNF revealed its widespread unspecific internalization by cortical and striatal neurons, exhibiting different patterns of subcellular rhCDNF distribution. Electron microscopy analysis showed that rhCDNF is present inside the endosomes and multivesicular bodies. In addition, we present data that after intrastriatal infusion the rhCDNF found in the SN is almost exclusively localized to the DA neurons, thus showing that it is retrogradely transported. PMID:28275710

  8. Retrograde venous cerebral air embolism from disconnected central venous catheter: an experimental model.

    PubMed

    Fracasso, Tony; Karger, Bernd; Schmidt, Peter F; Reinbold, Wolf D; Pfeiffer, Heidi

    2011-01-01

    There are few reported cases of death attributed to retrograde cerebral air embolism from central venous catheter. The pathophysiological mechanism and the necessary conditions are not fully understood, also because of missing experimental data. We performed experimental simulation while working on a possible case of retrograde cerebral air embolism. A hermetic system consisting of two containers connected to each other and to an electric pump by means of rubber hoses was built. In this system, a fluid (water and blood) could continuously flow under conditions similar to those of the common jugular vein. The part of the system representing the jugular vein could be freely positioned at angles between 0 and 90°. A central venous catheter was inserted into this part. After disconnection, the behavior of the air bubbles entering the hose through the tip of the catheter was evaluated at different positions. At angles between 0 and 45°, the air bubbles followed the fluid flow. At angles >45°, the air bubbles showed the tendency to flow upstream; this phenomenon was more evident the more vertically the hose was located. We were able to demonstrate that a retrograde air embolism can be caused by a disconnected catheter and is even more likely if the neck is in a vertical position. © 2010 American Academy of Forensic Sciences.

  9. Preventing post-endoscopic retrograde cholangiopancreatography pancreatitis: What can be done?

    PubMed Central

    Hauser, Goran; Milosevic, Marko; Stimac, Davor; Zerem, Enver; Jovanović, Predrag; Blazevic, Ivana

    2015-01-01

    Post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) is the most common complication of endoscopic retrograde cholangiopancreatography. The incidence of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis varies substantially and is reported around 1%-10%, although there are some reports with an incidence of around 30%. Usually, PEP is a mild or moderate pancreatitis, but in some instances it can be severe and fatal. Generally, it is defined as the onset of new pancreatic-type abdominal pain severe enough to require hospital admission or prolonged hospital stay with levels of serum amylase two to three times greater than normal, occurring 24 h after ERCP. Several methods have been adopted for preventing pancreatitis, such as pharmacological or endoscopic approaches. Regarding medical prevention, only non-steroidal anti-inflammatory drugs, namely diclofenac sodium and indomethacin, are recommended, but there are some other drugs which have some potential benefits in reducing the incidence of post-ERCP pancreatitis. Endoscopic preventive measures include cannulation (wire guided) and pancreatic stenting, while the adoption of the early pre-cut technique is still arguable. This review will attempt to present and discuss different ways of preventing post-ERCP pancreatitis. PMID:25632179

  10. Retrograde Signals: Integrators of Interorganellar Communication and Orchestrators of Plant Development.

    PubMed

    de Souza, Amancio; Wang, Jin-Zheng; Dehesh, Katayoon

    2016-11-02

    Interorganellar cooperation maintained via exquisitely controlled retrograde-signaling pathways is an evolutionary necessity for maintenance of cellular homoeostasis. This signaling feature has therefore attracted much research attention aimed at improving understanding of the nature of these communication signals, how the signals are sensed, and ultimately the mechanism by which they integrate targeted processes that collectively culminate in organellar cooperativity. The answers to these questions will provide insight into how retrograde-signal-mediated regulatory mechanisms are recruited and which biological processes are targeted, and will advance our understanding of how organisms balance metabolic investments in growth against adaptation to environmental stress. This review summarizes the present understanding of the nature and the functional complexity of retrograde signals as integrators of interorganellar communication and orchestrators of plant development, and offers a perspective on the future of this critical and dynamic area of research. Expected final online publication date for the Annual Review of Plant Biology Volume 68 is April 29, 2017. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

  11. Relay of retrograde synaptogenic signals through axonal transport of BMP receptors

    PubMed Central

    Smith, Rebecca B.; Machamer, James B.; Kim, Nam Chul; Hays, Thomas S.; Marqués, Guillermo

    2012-01-01

    Summary Neuronal function depends on the retrograde relay of growth and survival signals from the synaptic terminal, where the neuron interacts with its targets, to the nucleus, where gene transcription is regulated. Activation of the Bone Morphogenetic Protein (BMP) pathway at the Drosophila larval neuromuscular junction results in nuclear accumulation of the phosphorylated form of the transcription factor Mad in the motoneuron nucleus. This in turn regulates transcription of genes that control synaptic growth. How BMP signaling at the synaptic terminal is relayed to the cell body and nucleus of the motoneuron to regulate transcription is unknown. We show that the BMP receptors are endocytosed at the synaptic terminal and transported retrogradely along the axon. Furthermore, this transport is dependent on BMP pathway activity, as it decreases in the absence of ligand or receptors. We further demonstrate that receptor traffic is severely impaired when Dynein motors are inhibited, a condition that has previously been shown to block BMP pathway activation. In contrast to these results, we find no evidence for transport of phosphorylated Mad along the axons, and axonal traffic of Mad is not affected in mutants defective in BMP signaling or retrograde transport. These data support a model in which complexes of activated BMP receptors are actively transported along the axon towards the cell body to relay the synaptogenic signal, and that phosphorylated Mad at the synaptic terminal and cell body represent two distinct molecular populations. PMID:22573823

  12. Endovascular Treatment of Proximal Aortic Arch Lesions through a Retrograde Approach

    PubMed Central

    Samaniego, Edgar A.; Katzen, Barry T.; Kreusch, Andreas S.; Uthoff, Heiko

    2015-01-01

    Tandem atherosclerotic lesions of the carotid bifurcation and the ipsilateral proximal common carotid artery (CCA) or innominate arteries (IA) can be challenging to treat. A surgical approach may treat the lesion at the carotid bifurcation, but proximal CCA or IA lesions require a major surgical exposure. An endovascular approach is challenging as well since anatomic variations, such as a type III aortic arch, can render navigation very difficult. We report our experience in the hybrid surgical and endovascular treatment of complex proximal CCA and IA lesions. Eleven patients who underwent hybrid procedures with surgical exposure (with or without endarterectomy) of the carotid artery and retrograde endovascular intervention of a proximal lesion were included in the study. The mean percentage of stenosis was 81%. Seven patients underwent a carotid endarterectomy (CEA), and 4 patients underwent only a surgical cutdown for retrograde endovascular access of the IA or left CCA. All procedures were technically successful. Eight patients had no symptoms within 30 days of the procedure. The hybrid retrograde endovascular approach through carotid exposure with or without CEA appears to be effective and safe in selected patients who have a high-risk complex anatomy of tandem lesions. PMID:25999991

  13. Retrograde regulation of nuclear gene expression in CW-CMS of rice.

    PubMed

    Fujii, Sota; Komatsu, Setsuko; Toriyama, Kinya

    2007-02-01

    The CW-cytoplasmic male sterility (CMS) line has the cytoplasm of Oryza rufipogon Griff, and mature pollen is morphologically normal under an optical microscope but lacks the ability to germinate; restorer gene Rf17 has been identified as restoring this ability. The difference between nuclear gene expression in mature anthers was compared for the CW-CMS line, [cms-CW] rf17rf17, and a maintainer line with normal cytoplasm of Oryza sativa L., [normal] rf17rf17. Using a 22-k rice oligoarray we detected 58 genes that were up-regulated more than threefold in the CW-CMS line. Expression in other organs was further investigated for 20 genes using RT-PCR. Five genes, including genes for alternative oxidase, were found to be preferentially expressed in [cms-CW] rf17rf17 but not in [normal] rf17rf17 or [cms-CW] Rf17Rf17. Such [cms-CW] rf17rf17-specific gene expression was only observed in mature anthers but not in leaves, stems, or roots, indicating the presence of anther-specific mitochondrial retrograde regulation of nuclear gene expression, and that Rf17 has a role in restoring the ectopic gene expression. We also used a proteomic approach to discover the retrograde regulated proteins and identified six proteins that were accumulated differently. These results reveal organ-specific induced mitochondrial retrograde pathways affecting nuclear gene expression possibly related to CMS.

  14. Imipramine for successful treatment of retrograde ejaculation caused by retroperitoneal surgery.

    PubMed

    Ochsenkühn, R; Kamischke, A; Nieschlag, E

    1999-06-01

    Retrograde ejaculation is a known complication following retroperitoneal lymph node dissection. Without further therapy, achieving paternity may be impossible. We evaluated the use of the tricyclic antidepressant imipramine in a new ovarian cycle-dependent dose regime for reversal of retrograde ejaculation in 11 patients desiring fertility. Ten patients with retroperitoneal lymph node dissection performed because of testicular cancer, and one with aortic surgery (thromboendarterectomy) were treated in an open, uncontrolled study with imipramine given at a daily oral dose increasing from 25 to 50 mg for 7 days prior to the planned ejaculation or the expected ovulation of the female partner. In all 11 patients, antegrade ejaculation could be induced (sperm counts: 3.9-276.0 x 10(6)/mL). Major side-effects were not observed, but half of the patients complained of minor degrees of dizziness, weakness, nausea or sweating during medication. Under treatment, two patients with normal sperm concentrations induced a spontaneous pregnancy. One ICSI cycle each was performed in 2 patients, with successful fertilization, out no pregnancy. In conclusion, temporary oral intake of imipramine is an effective and safe treatment to re-establish antegrade ejaculation in patients with retrograde ejaculation following retroperitoneal surgery, thus providing possibilities for paternity either through intercourse or by assisted fertilization.

  15. Intrastriatally Infused Exogenous CDNF Is Endocytosed and Retrogradely Transported to Substantia Nigra.

    PubMed

    Mätlik, Kert; Vihinen, Helena; Bienemann, Ali; Palgi, Jaan; Voutilainen, Merja H; Booms, Sigrid; Lindahl, Maria; Jokitalo, Eija; Saarma, Mart; Huttunen, Henri J; Airavaara, Mikko; Arumäe, Urmas

    2017-01-01

    Cerebral dopamine neurotrophic factor (CDNF) protects the nigrostriatal dopaminergic (DA) neurons in rodent models of Parkinson's disease and restores DA circuitry when delivered after these neurons have begun to degenerate. These DA neurons have been suggested to transport striatal CDNF retrogradely to the substantia nigra (SN). However, in cultured cells the binding and internalization of extracellular CDNF has not been reported. The first aim of this study was to examine the cellular localization and pharmacokinetic properties of recombinant human CDNF (rhCDNF) protein after its infusion into rat brain parenchyma. Second, we aimed to study whether the transport of rhCDNF from the striatum to the SN results from its retrograde transport via DA neurons or from its anterograde transport via striatal GABAergic projection neurons. We show that after intrastriatal infusion, rhCDNF diffuses rapidly and broadly, and is cleared with a half-life of 5.5 h. Confocal microscopy analysis of brain sections at 2 and 6 h after infusion of rhCDNF revealed its widespread unspecific internalization by cortical and striatal neurons, exhibiting different patterns of subcellular rhCDNF distribution. Electron microscopy analysis showed that rhCDNF is present inside the endosomes and multivesicular bodies. In addition, we present data that after intrastriatal infusion the rhCDNF found in the SN is almost exclusively localized to the DA neurons, thus showing that it is retrogradely transported.

  16. Retrograde trafficking of β-dystroglycan from the plasma membrane to the nucleus.

    PubMed

    Gracida-Jiménez, Viridiana; Mondragón-González, Ricardo; Vélez-Aguilera, Griselda; Vásquez-Limeta, Alejandra; Laredo-Cisneros, Marco S; Gómez-López, Juan de Dios; Vaca, Luis; Gourlay, Sarah C; Jacobs, Laura A; Winder, Steve J; Cisneros, Bulmaro

    2017-08-29

    β-Dystroglycan (β-DG) is a transmembrane protein with critical roles in cell adhesion, cytoskeleton remodeling and nuclear architecture. This functional diversity is attributed to the ability of β-DG to target to, and conform specific protein assemblies at the plasma membrane (PM) and nuclear envelope (NE). Although a classical NLS and importin α/β mediated nuclear import pathway has already been described for β-DG, the intracellular trafficking route by which β-DG reaches the nucleus is unknown. In this study, we demonstrated that β-DG undergoes retrograde intracellular trafficking from the PM to the nucleus via the endosome-ER network. Furthermore, we provided evidence indicating that the translocon complex Sec61 mediates the release of β-DG from the ER membrane, making it accessible for importins and nuclear import. Finally, we show that phosphorylation of β-DG at Tyr(890) is a key stimulus for β-DG nuclear translocation. Collectively our data describe the retrograde intracellular trafficking route that β-DG follows from PM to the nucleus. This dual role for a cell adhesion receptor permits the cell to functionally connect the PM with the nucleus and represents to our knowledge the first example of a cell adhesion receptor exhibiting retrograde nuclear trafficking and having dual roles in PM and NE.

  17. Retrograde plasticity and differential competition of bipolar cell dendrites and axons in the developing retina.

    PubMed

    Johnson, Robert E; Kerschensteiner, Daniel

    2014-10-06

    Most neurons function in the context of pathways that process and propagate information through a series of stages, e.g., from the sensory periphery to cerebral cortex. Because activity at each stage of a neural pathway depends on connectivity at the preceding one, we hypothesized that during development, axonal output of a neuron may regulate synaptic development of its dendrites (i.e., retrograde plasticity). Within pathways, neurons often receive input from multiple partners and provide output to targets shared with other neurons (i.e., convergence). Converging axons can intermingle or occupy separate territories on target dendrites. Activity-dependent competition has been shown to bias target innervation by overlapping axons in several systems. By contrast, whether territorial axons or dendrites compete for targets and inputs, respectively, has not been tested. Here, we generate transgenic mice in which glutamate release from specific sets of retinal bipolar cells (BCs) is suppressed. We find that dendrites of silenced BCs recruit fewer inputs when their neighbors are active and that dendrites of active BCs recruit more inputs when their neighbors are silenced than either active or silenced BCs with equal neighbors. By contrast, axons of silenced BCs form fewer synapses with their targets, irrespective of the activity of their neighbors. These findings reveal that retrograde plasticity guides BC dendritic development in vivo and demonstrate that dendrites, but not territorial axons, in a convergent neural pathway engage in activity-dependent competition. We propose that at a population level, retrograde plasticity serves to maximize functional representation of inputs.

  18. Vesicular stomatitis virus with the rabies virus glycoprotein directs retrograde transsynaptic transport among neurons in vivo

    PubMed Central

    Beier, Kevin T.; Saunders, Arpiar B.; Oldenburg, Ian A.; Sabatini, Bernardo L.; Cepko, Constance L.

    2012-01-01

    Defining the connections among neurons is critical to our understanding of the structure and function of the nervous system. Recombinant viruses engineered to transmit across synapses provide a powerful approach for the dissection of neuronal circuitry in vivo. We recently demonstrated that recombinant vesicular stomatitis virus (VSV) can be endowed with anterograde or retrograde transsynaptic tracing ability by providing the virus with different glycoproteins. Here we extend the characterization of the transmission and gene expression of recombinant VSV (rVSV) with the rabies virus glycoprotein (RABV-G), and provide examples of its activity relative to the anterograde transsynaptic tracer form of rVSV. rVSV with RABV-G was found to drive strong expression of transgenes and to spread rapidly from neuron to neuron in only a retrograde manner. Depending upon how the RABV-G was delivered, VSV served as a polysynaptic or monosynaptic tracer, or was able to define projections through axonal uptake and retrograde transport. In animals co-infected with rVSV in its anterograde form, rVSV with RABV-G could be used to begin to characterize the similarities and differences in connections to different areas. rVSV with RABV-G provides a flexible, rapid, and versatile tracing tool that complements the previously described VSV-based anterograde transsynaptic tracer. PMID:23403489

  19. Effect of single-, dual-, and triple-retrogradation treatments on in vitro digestibility and structural characteristics of waxy wheat starch.

    PubMed

    Hu, Xiao-Pei; Xie, Yao-Yu; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing

    2014-08-15

    The effects of single-retrogradation (SR), dual-retrogradation (DR) and triple-retrogradation (TR) treatments on in vitro digestibility and structural characteristics of waxy wheat starch were investigated. The yield of slowly digestible starch in a DR-treated starch with retrogradation time interval of 48 h reached a maximum of 44.41%. The gelatinization temperature range and gelatinization enthalpy of DR-treated starch samples were the lowest. Moreover, compared with native starch, X-ray diffraction patterns of treated starches were altered from A-type to B-type and relative crystallinity was significantly decreased, which was responsible for the interaction between amylose-amylose and/or amylose-amylopectin chains that may generate more imperfect structures. Scanning electron micrographs revealed that compared with SR-treated and TR-treated starches, the surface of DR-treated starch with a retrogradation time interval of 48 h exhibited a net-like structure with numerous cavities. These results suggest that structural changes of waxy wheat starch by cycled retrogradation treatment significantly affect digestibility, and DR treatment can be used for preparing SDS product. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Local retrograde and destination transfer of physiological regulators as an important regulatory system and its role. Facts and hypothesis.

    PubMed

    Krzymowski, T; Stefanczyk-Krzymowska, S

    2012-02-01

    In recent decades, among many physiological regulatory systems operating as local and central controls, the mechanism of the local regulatory system based on the uptake and retrograde transfer of hormones and other physiological regulators to the places of their secretion or their destination transfer to nearby structures has become precisely understood. The system of the retrograde transfer and local destination transfer of the physiological regulators, situated between endocrine and paracrine regulation, operates primarily on the basis of specific morphological adaptations of the local blood circulatory system and lymphatic system. These adaptations enable the transfer of the regulatory molecules through the walls of blood and lymph vessels and locally increase their concentrations in the arterial blood supplying the organ secreting them (retrograde transfer) or a nearby organ (destination transfer). Extensive studies on the structure and functions of the retrograde and destination transfer system have focused on several key areas: the female and male reproductive organs, the perihypophyseal vascular complex (the venous cavernous sinus and the internal carotid artery or the rete mirabile of the internal carotid artery or maxillary artery), and the periophthalmic vascular complex (the venous ophthalmic sinus or plexus and the rete mirabile of the external ophthalmic artery). The local retrograde transfer of regulatory molecules not only allows them to be reused but also influences their production by a feedback mechanism. The local destination transfer of physiological regulators can selectively supply nearby organs with certain regulatory factors and thereby affect their function. Many observations indicate that the retrograde and local destination transfer of hormones and other biologically active substances may be a universal physiological regulatory mechanism, operating with only minor modifications in various species of animals and in humans. This review

  1. Metabolic Characteristics of Human Hearts Preserved for 12 Hours by Static Storage, Antegrade Perfusion or Retrograde Coronary Sinus Perfusion

    PubMed Central

    Cobert, Michael L.; Merritt, Matthew E.; West, LaShondra M.; Ayers, Colby; Jessen, Michael E.; Peltz, Matthias

    2014-01-01

    Objective(s) Machine perfusion of donor hearts is a promising strategy to increase the donor pool. Antegrade perfusion is effective but can lead to aortic valve incompetence and non-nutrient flow. Experience with retrograde coronary sinus perfusion of donor hearts has been limited. We tested the hypothesis that retrograde perfusion could support myocardial metabolism over an extended donor ischemic interval. Methods Human hearts from donors rejected or not offered for transplantation were preserved for 12 hours in University of Wisconsin Machine Perfusion Solution by: 1. Static hypothermic storage 2. Hypothermic antegrade machine perfusion or 3. Hypothermic retrograde machine perfusion. Myocardial oxygen consumption (MVO2), and lactate accumulation were measured. Ventricular tissue was collected for proton (1H) and phosphorus-31 (31P) magnetic resonance spectroscopy (MRS) to evaluate the metabolic state of the myocardium. Myocardial water content was determined at end-experiment. Results Stable perfusion parameters were maintained throughout the perfusion period with both perfusion techniques. Lactate/alanine ratios were lower in perfused hearts compared to static hearts (p<.001). Lactate accumulation (Antegrade 2.0±.7, Retrograde 1.7±.1 mM) and MVO2 (Antegrade 0.25±.2, Retrograde 0.26±.3 mL O2/min/100g) were similar in machine perfused groups. High energy phosphates were better preserved in both perfused groups (p<.05). Left ventricular myocardial water content was increased in retrograde perfused (80.2±.8%) compared to both antegrade perfused (76.6±.8%, p=.02) and static storage hearts (76.7±1%, p=.02). Conclusions In conclusion, machine perfusion by either the antegrade or the retrograde technique can support myocardial metabolism over long intervals. Machine perfusion appears promising for long term preservation of human donor hearts. PMID:24642559

  2. Outcome and Safety of Anterograde and Retrograde Single-Balloon Enteroscopy: Clinical Experience at a Tertiary Medical Center in Taiwan

    PubMed Central

    Lin, Meng-Chiung; Chen, Peng-Jen; Shih, Yu-Lueng; Huang, Hsin-Hung; Chang, Wei-Kuo; Hsieh, Tsai-Yuan; Huang, Tien-Yu

    2016-01-01

    Single-balloon enteroscopy (SBE) is designed for identifying possible small bowel lesions with balloon-assisted enteroscopy that allows deep intubation of the intestine. However, data regarding the outcome and safety of SBE remain limited. We conducted this study to evaluate the outcome and safety of anterograde and retrograde SBE approaches. This retrospective review from a tertiary medical center in Taiwan included endoscopic reports and chart data from 128 patients with 200 anterograde and retrograde procedures from September 2009 to November 2014. In this study, the most common indication for both anterograde and retrograde SBE was obscure gastrointestinal bleeding (64.4% vs. 60.6%). There were no significant differences between anterograde and retrograde approaches in terms of the diagnostic yield (69.3% vs. 52.5%) and intervention rate (23.8% vs. 17.2%). The procedure time was shorter for anterograde SBE than for retrograde SBE (68.1 ± 23.9 vs. 76.8 ± 27.7 min, P = 0.018). In addition, among the subgroup of patients with obscure gastrointestinal bleeding, the most common etiologies for those in different age-groups were angiodysplasia (≥ 65 years), non-specific ulcers (30–64 years), and Meckel’s diverticulum (< 30 years). The major complication rate during the study was 1.5%; the rate of asymptomatic hyperamylasemia was higher for patients who underwent anterograde SBE than for those who underwent retrograde SBE (13.9% vs. 2%, P = 0.005). The outcome and safety of anterograde and retrograde SBE are similar. However, anterograde SBE has a shorter procedural time and a higher rate of asymptomatic hyperamylasemia. PMID:27548619

  3. Evaluation of Ophthalmic Artery Branch Retrograde Intervention in the Treatment of Central Retinal Artery Occlusion (CRAO)

    PubMed Central

    Wang, Runsheng; Qian, Lu; Wang, Yi; Zheng, Yi; Du, Shanshuang; Lei, Tao; Lv, Peilin; Long, Tan; Wang, Wenjun

    2017-01-01

    Background Central retinal artery occlusion (CRAO) is the occlusion of the central retinal artery resulting in retinal infarction and acute vision loss. Digital subtraction angiography (DSA)–guided superselective ophthalmic artery or selective carotid thrombolysis remains the preferred treatment method for CRAO. This study aimed to evaluate the safety and clinical efficacy of the novel ophthalmic artery branch retrograde thrombolytic intervention for CRAO. Material/Methods Fifty patients with monocular CRAO were enrolled, including 28 males and 22 females (mean age: 55.7±2.3 years). The patients were randomly divided into two groups for thrombolysis with urokinase (400,000 U) and papaverine (30 mg) by either ophthalmic artery branch retrograde intervention (group A, n=26) or superselective ophthalmic artery/selective carotid intervention (group B, n=24). There was no significant difference in age (P=0.58), gender ratio (P=0.49), and time to onset (P=1.00) between the two groups. The adverse reactions and clinical efficacy were evaluated by postoperative DSA, fundus fluorescein angiography (FFA), and visual acuity tests. Results No serious complications, abnormal eye movement, or vitreous hemorrhage occurred in either group. DSA showed that group A had an effective rate (92.30%) comparable to that of group B (100%, χ2=2.08, P=0.25). FFA suggested that both groups had similar treatment efficacy (χ2=3.09, P=0.21). Visual acuity tests also confirmed a similar efficacy of the two intervention approaches (χ2=0.25, P=0.88). Conclusions The developed novel ophthalmic artery branch retrograde intervention is highly effective and safe for CRAO, and may be a superior method compared with the conventional approach. PMID:28064304

  4. Effect of retrograde aminophylline administration on calcium and phosphate solubility in neonatal total parenteral nutrient solutions.

    PubMed

    Kirkpatrick, A E; Holcombe, B J; Sawyer, W T

    1989-12-01

    The effect of retrograde administration of aminophylline injection on calcium and phosphate solubility in neonatal total parenteral nutrient (TPN) solutions was studied. Neonatal TPN solutions containing two amino acids solutions in three concentrations (Travasol 1% and 2% and TrophAmine 2%) were formulated. Calcium and phosphate salts were added to achieve calcium concentrations of 10, 15, 20, 25, 30, or 40 meq/L and phosphorus concentrations of 10, 15, 20, 25, 30, or 40 mmol/L. Samples were inspected visually after 18-24 hours; solutions free of precipitation were then infused through two parallel syringe-pump systems designed to simulate clinical conditions for TPN solution administration to a 1-kg neonate. To one system, a 7.5-mg aminophylline dose was added as a manual retrograde injection; sterile water for injection was added as a manual retrograde injection to the other system. The solutions were inspected throughout a one-hour infusion period for precipitate formation in the i.v. apparatus, and the pH of the effluents was determined. Concurrent aminophylline administration resulted in visible precipitate in all but a few of the solutions tested. The solution containing Travasol 2%, calcium 10 meq/L, and phosphorus 10 mmol/L remained clear, as did the solutions containing TrophAmine 2% and the following concentrations of calcium and phosphorus: calcium 10 meq/L and phosphorus 10, 15, or 20 mmol/L; calcium 15 meq/L and phosphorus 10 or 15 mmol/L; and calcium 20 meq/L and phosphorus 10 or 15 mmol/L. An average increase in pH of 0.63 unit was noted in all solutions.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Branched Motifs Enable Long-Range Interactions in Signaling Networks through Retrograde Propagation

    PubMed Central

    Jesan, Tharmaraj; Sarma, Uddipan; Halder, Subhadra; Saha, Bhaskar; Sinha, Sitabhra

    2013-01-01

    Branched structures arise in the intra-cellular signaling network when a molecule is involved in multiple enzyme-substrate reaction cascades. Such branched motifs are involved in key biological processes, e.g., immune response activated by T-cell and B-cell receptors. In this paper, we demonstrate long-range communication through retrograde propagation between branches of signaling pathways whose molecules do not directly interact. Our numerical simulations and experiments on a system comprising branches with JNK and p38MAPK as terminal molecules respectively that share a common MAP3K enzyme MEKK3/4 show that perturbing an enzyme in one branch can result in a series of changes in the activity levels of molecules “upstream” to the enzyme that eventually reaches the branch-point and affects other branches. In the absence of any evidence for explicit feedback regulation between the functionally distinct JNK and p38MAPK pathways, the experimentally observed modulation of phosphorylation amplitudes in the two pathways when a terminal kinase is inhibited implies the existence of long-range coordination through retrograde information propagation previously demonstrated in single linear reaction pathways. An important aspect of retrograde propagation in branched pathways that is distinct from previous work on retroactivity focusing exclusively on single chains is that varying the type of perturbation, e.g., between pharmaceutical agent mediated inhibition of phosphorylation or suppression of protein expression, can result in opposing responses in the other branches. This can have potential significance in designing drugs targeting key molecules which regulate multiple pathways implicated in systems-level diseases such as cancer and diabetes. PMID:23741327

  6. Trafficking of cell surface beta-amyloid precursor protein: retrograde and transcytotic transport in cultured neurons

    PubMed Central

    1995-01-01

    Amyloid beta-protein (A beta), the principal constituent of senile plaques seen in Alzheimer's disease (AD), is derived by proteolysis from the beta-amyloid precursor protein (beta PP). The mechanism of A beta production in neurons, which are hypothesized to be a rich source of A beta in brain, remains to be defined. In this study, we describe a detailed localization of cell surface beta PP and its subsequent trafficking in primary cultured neurons. Full-length cell surface beta PP was present primarily on perikarya and axons, the latter with a characteristic discontinuous pattern. At growth cones, cell surface beta PP was inconsistently detected. By visualizing the distribution of beta PP monoclonal antibodies added to intact cultures, beta PP was shown to be internalized from distal axons or terminals and retrogradely transported back to perikarya in organelles which colocalized with fluid-phase endocytic markers. Retrograde transport of beta PP was shown in both hippocampal and peripheral sympathetic neurons, the latter using a compartment culture system that isolated cell bodies from distal axons and terminals. In addition, we demonstrated that beta PP from distal axons was transcytotically transported to the surface of perikarya from distal axons in sympathetic neurons. Indirect evidence of this transcytotic pathway was obtained in hippocampal neurons using antisense oligonucleotide to the kinesin heavy chain to inhibit anterograde beta PP transport. Taken together, these results demonstrate novel aspects of beta PP trafficking in neurons, including retrograde axonal transport and transcytosis. Moreover, the axonal predominance of cell surface beta PP is unexpected in view of the recent report of polarized sorting of beta PP to the basolateral domain of MDCK cells. PMID:7721945

  7. Retrograde intrarenal surgery and micro-percutaneous nephrolithotomy for renal lithiasis smaller than 2 CM.

    PubMed

    Cepeda, M; Amón, J H; Mainez, J A; de la Cruz, B; Rodríguez, V; Alonso, D; Martínez-Sagarra, J M

    2017-10-01

    Microperc is the upgraded form of percutaneous nephrolithotomy miniaturization. The aim of this study is to compare prospectively microperc and retrograde intrarenal surgery for the treatment of renal stones smaller than 2 cm. A comparative prospective study of both techniques was carried out between January 2014 and June 2015. Thirty-five patients were divided in two groups: Group A, 17 patients treated by retrograde intrarenal surgery and Group B, 18 patients treated by microperc. Stone clearance was assessed using CT scan 3 months after surgery. Both groups were statistically comparable as demographic variables and stone size was similar (16.76 mm Group A vs 15.72 mm Group B). Success rate, hospital stay and JJ stenting were similar for both groups. There was no statistically significant difference regarding post-operatory complications: 17.64% Group A vs 5.56% Group B (p=0,062), all of them Clavien I and II. Surgical time was statistically different (63.82 min Group A vs 103.24 min Group B) as well as hemoglobin drop (0.62 g/dl Group A and 1.89 g/dl Group B). Microperc is an effective and safe procedure for the treatment of renal lithiasis smaller than 2 cm, which makes it a good alternative to retrograde intrarenal surgery for this stone size. However, more prospective studies that include a larger cohort are necessary to confirm our results. Copyright © 2017 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

  8. Functional results after cholesteatoma surgery in an adult population using the retrograde mastoidectomy technique.

    PubMed

    Minovi, Amir; Venjacob, Johanna; Volkenstein, Stefan; Dornhoffer, John; Dazert, Stefan

    2014-03-01

    In this retrospective study, we analyzed the functional results after using the retrograde mastoidectomy technique for cholesteatoma removal in an adult patient population. The described technique was used at a tertiary referral center for cholesteatoma removal in 218 adult patients, representing 242 operated ears, with an average follow-up time of 20.3 months. With the retrograde mastoidectomy technique, the cholesteatoma is removed posteriorly through the canal wall, from the epitympanic region toward the mastoid, with the option to reconstruct the posterior bony canal wall or create an open mastoid cavity, depending on the size of the defect. Primary surgery was carried out in 58.7 % ears, with the remaining 41.3 % representing revision surgery. In 151 cases, the posterior canal wall was reconstructed, and in 91 cases a classical CWD with an open mastoid cavity was created. In the majority of the cases (n = 213, 88.0 %), a primary hearing restoration was performed. There were 18 recurrences (12.7 %) in primary cases and 22 recurrences (22 %) in revision surgeries. Ninety percent of the recurrences (36 of 40 cases) occurred within 5 years. A postoperative air-bone gap of less than 20 dB was achieved in 61.6 % of the operated ears. Ears with a reconstructed posterior canal wall had significantly better hearing results than those cases in which a CWD procedure was used (air-bone gap of 17.6 versus 22.5 dB, p < 0.05). The retrograde mastoidectomy technique for cholesteatoma removal resulted in satisfying hearing results in the majority of the cases, with a recurrence rate comparable to the current literature.

  9. [Clinical research of needle-pricking therapy for functional retrograde ejaculatioin].

    PubMed

    Cheng, Dong; Hu, Lei; Xian, Feng; Zhong, Jian; Zhang, Yuejuan; Wang, Gangwei; Ma, Jiyuan; Xu, Hao

    2016-02-01

    To observe the clinical effects of needle-pricking therapy, a newly medical and minimally invasive technique, for functional retrograde ejaculation and to explore its mechanism. Methods Thirty-six patients with functional retrograde ejaculation were randomly divided into an observation group(19 cases) and a control group(17 cases) In the observation group,needle-pricking therapy was used at Guanyuan(CV 4) and bilateral sacral plexus nerve,lumbar 1 nerve and greater occipital nerve stimulating points,once a week. In the control group, midodrine tablets were prescribed orally,three times a day. All the treatment was given for 9 weeks. The clinical effects of the two groups were observed, and the levels of luteinizing hormone(LH), testosterone(Tes) and estra4 diol(E2) were compared between the two groups. The total effective rate of the observation group was, 89. 47%(17/19), which was better than 47.06% (8/17) of the control group(P<0. 05). The LH and Tes were obviously increased and E2 was decreased compared with those before treatment in the observation group(all P< 0. 01). Tes was raised(P<0. 05) and E2 was apparently declined in the control group(P<0. 01). After treatment, the differences of serum LH and Tes were statistically significant between the two groups(both P<0. 01). Needle-pricking therapy has advantages for functional retrograde ejaculation probably in that stimulating lumbosacral nerves can strengthen the function of pelvic floor muscles and urethral expansion muscle and regulate sexual gland axis.

  10. Efficacy of retrograde ureteropyeloscopic holmium laser lithotripsy for intrarenal calculi >2 cm.

    PubMed

    Bader, M J; Gratzke, C; Walther, S; Weidlich, P; Staehler, M; Seitz, M; Sroka, R; Reich, O; Stief, C G; Schlenker, B

    2010-10-01

    The objectives of this study are to assess the efficacy and safety of retrograde ureteroscopic holmium laser lithotripsy for intrarenal calculi greater than 2 cm in diameter. A total of 24 patients with a stone burden >2 cm were treated with retrograde ureteroscopic laser lithotripsy. Primary study endpoints were number of treatments until the patient was stone free and perioperative complications with a follow-up of at least 3 months after intervention. In 24 patients (11 women and 13 men, 20-78 years of age), a total of 40 intrarenal calculi were treated with retrograde endoscopic procedures. At the time of the initial procedure, calculi had an average total linear diameter of 29.75 ± 1.57 mm and an average stone volume of 739.52 ± 82.12 mm(3). The mean number of procedures per patient was 1.7 ± 0.8 (range 1-3 procedures). The overall stone-free rate was 92%. After 1, 2 and 3 procedures 54, 79 and 92% of patients were stone free, respectively. There were no major complications. Minor postoperative complications included pyelonephritis in three cases (7.5%), of whom all responded immediately to parenteral antibiotics. In one patient the development of steinstrasse in the distal ureter required ureteroscopic fragment disruption and basketing. Ureteroscopy with holmium laser lithotripsy represents an efficient treatment option and allows the treatment of large intrarenal calculi of all compositions and throughout the whole collecting system even for patients with a stone burden of more than 2 cm size.

  11. Predicting Retrograde Autobiographical Memory Changes Following Electroconvulsive Therapy: Relationships between Individual, Treatment, and Early Clinical Factors.

    PubMed

    Martin, Donel M; Gálvez, Verònica; Loo, Colleen K

    2015-06-19

    Loss of personal memories experienced prior to receiving electroconvulsive therapy is common and distressing and in some patients can persist for many months following treatment. Improved understanding of the relationships between individual patient factors, electroconvulsive therapy treatment factors, and clinical indicators measured early in the electroconvulsive therapy course may help clinicians minimize these side effects through better management of the electroconvulsive therapy treatment approach. In this study we examined the associations between the above factors for predicting retrograde autobiographical memory changes following electroconvulsive therapy. Seventy-four depressed participants with major depressive disorder were administered electroconvulsive therapy 3 times per week using either a right unilateral or bitemporal electrode placement and brief or ultrabrief pulse width. Verbal fluency and retrograde autobiographical memory (assessed using the Columbia Autobiographical Memory Interview - Short Form) were tested at baseline and after the last electroconvulsive therapy treatment. Time to reorientation was measured immediately following the third and sixth electroconvulsive therapy treatments. Results confirmed the utility of measuring time to reorientation early during the electroconvulsive therapy treatment course as a predictor of greater retrograde amnesia and the importance of assessing baseline cognitive status for identifying patients at greater risk for developing later side effects. With increased number of electroconvulsive therapy treatments, older age was associated with increased time to reorientation. Consistency of verbal fluency performance was moderately correlated with change in Columbia Autobiographical Memory Interview - Short Form scores following right unilateral electroconvulsive therapy. Electroconvulsive therapy treatment techniques associated with lesser cognitive side effects should be particularly considered for

  12. Predicting Retrograde Autobiographical Memory Changes Following Electroconvulsive Therapy: Relationships between Individual, Treatment, and Early Clinical Factors

    PubMed Central

    Gálvez, Verònica; Loo, Colleen K.

    2015-01-01

    Background: Loss of personal memories experienced prior to receiving electroconvulsive therapy is common and distressing and in some patients can persist for many months following treatment. Improved understanding of the relationships between individual patient factors, electroconvulsive therapy treatment factors, and clinical indicators measured early in the electroconvulsive therapy course may help clinicians minimize these side effects through better management of the electroconvulsive therapy treatment approach. In this study we examined the associations between the above factors for predicting retrograde autobiographical memory changes following electroconvulsive therapy. Methods: Seventy-four depressed participants with major depressive disorder were administered electroconvulsive therapy 3 times per week using either a right unilateral or bitemporal electrode placement and brief or ultrabrief pulse width. Verbal fluency and retrograde autobiographical memory (assessed using the Columbia Autobiographical Memory Interview – Short Form) were tested at baseline and after the last electroconvulsive therapy treatment. Time to reorientation was measured immediately following the third and sixth electroconvulsive therapy treatments. Results: Results confirmed the utility of measuring time to reorientation early during the electroconvulsive therapy treatment course as a predictor of greater retrograde amnesia and the importance of assessing baseline cognitive status for identifying patients at greater risk for developing later side effects. With increased number of electroconvulsive therapy treatments, older age was associated with increased time to reorientation. Consistency of verbal fluency performance was moderately correlated with change in Columbia Autobiographical Memory Interview – Short Form scores following right unilateral electroconvulsive therapy. Conclusions: Electroconvulsive therapy treatment techniques associated with lesser cognitive side

  13. Environmental factors that affect the ability of amylose to contribute to retrogradation in gels made from rice flour.

    PubMed

    Philpot, Kim; Martin, Margrit; Butardo, Vito; Willoughby, Doug; Fitzgerald, Melissa

    2006-07-12

    Retrogradation in rice is a trait that describes the hardening of cooked rice after storage or cooling, and it has significant implications for many consumers of rice, since many people cook rice in the morning and consume it several hours later or the next day. Tools to select against retrogradation in breeding programs are yet to be described. Here, we aim to determine the effect on retrogradation of storage time and temperature and the role of starch, protein, and lipids using gels made from Koshihikari grown in either Australia or Japan. Immediately after cooking, cooling from 60 to 40 degrees C had a minimal effect on firmness, but cooling to 20 degrees C led to significantly firmer gels. Storing the gels at low temperatures did not have an additional effect on the firmness as compared with storing the gels at 20, 40, or 60 degrees C. The removal of proteins led to significantly softer gels at all storage treatments but did not affect the change in firmness on cooling. The removal of lipids increased the rate of retrogradation and the firmness of gels significantly for all treatments. Koshihikari grown in Japan retrograded much less than Koshihikari grown in Australia. The amount of amylose that could be washed from gels made from Australian flour was much greater than for gels made from Japanese flour. After storage, only low molecular weight amylose chains were released from the gel and only after rewarming them to 60 degrees C. Despite the fact that flours from both origins were 18% amylose, the amount of long amylose chains that were complexed with lipids was much greater for the Japanese rice, and the unavailability of the complexed long amylose chains explained the lack of retrogradation in the Japanese rice. Once the long chains were released from amylose-lipid complexes, the Japanese rice retrograded. Thus, the environmental factor affecting retrogradation in this variety is type or amount of lipids synthesized, and the degree of retrogradation was

  14. Retrograde Transport from Early Endosomes to the trans-Golgi Network Enables Membrane Wrapping and Egress of Vaccinia Virus Virions

    PubMed Central

    Sivan, Gilad; Weisberg, Andrea S.; Americo, Jeffrey L.

    2016-01-01

    ABSTRACT The anterograde pathway, from the endoplasmic reticulum through the trans-Golgi network to the cell surface, is utilized by trans-membrane and secretory proteins. The retrograde pathway, which directs traffic in the opposite direction, is used following endocytosis of exogenous molecules and recycling of membrane proteins. Microbes exploit both routes: viruses typically use the anterograde pathway for envelope formation prior to exiting the cell, whereas ricin and Shiga-like toxins and some nonenveloped viruses use the retrograde pathway for cell entry. Mining a human genome-wide RNA interference (RNAi) screen revealed a need for multiple retrograde pathway components for cell-to-cell spread of vaccinia virus. We confirmed and extended these results while discovering that retrograde trafficking was required for virus egress rather than entry. Retro-2, a specific retrograde trafficking inhibitor of protein toxins, potently prevented spread of vaccinia virus as well as monkeypox virus, a human pathogen. Electron and confocal microscopy studies revealed that Retro-2 prevented wrapping of virions with an additional double-membrane envelope that enables microtubular transport, exocytosis, and actin polymerization. The viral B5 and F13 protein components of this membrane, which are required for wrapping, normally colocalize in the trans-Golgi network. However, only B5 traffics through the secretory pathway, suggesting that F13 uses another route to the trans-Golgi network. The retrograde route was demonstrated by finding that F13 was largely confined to early endosomes and failed to colocalize with B5 in the presence of Retro-2. Thus, vaccinia virus makes novel use of the retrograde transport system for formation of the viral wrapping membrane. IMPORTANCE Efficient cell-to-cell spread of vaccinia virus and other orthopoxviruses depends on the wrapping of infectious particles with a double membrane that enables microtubular transport, exocytosis, and actin

  15. The effect of Er, Cr:YSGG laser irradiation on the apical leakage of retrograde cavity

    PubMed Central

    Asnaashari, Mohammad; Fekrazad, Reza; Dehghan Menshadi, Fatemeh; Seifi, Massoud

    2009-01-01

    INTRODUCTION: Controversial results have been reported when organic acids, ultrasonic instruments and laser techniques were used to remove smear layer in endodontic treatments. The aim of this study was to evaluate the effect of removing debris and smear layer by Er,Cr:YSGG laser irradiation on the apical leakage of retrograde cavities. MATERIALS AND METHODS: In this ex vivo study, 24 extracted mandibular single-rooted teeth were selected and instrumented up to K-file size #35. Approximately 3 mm of root apices were dissected perpendicular to the root’s long axis. Retrograde cavities with 3 mm depth were prepared and the teeth were randomly assigned to two groups. In one group, the retrograde cavities were filled with amalgam and in the other group, the dentinal surface of the retrograde cavities were lased with Er,Cr:YSGG laser (2W, 15 seconds, G4 tip). The cavities were filled with amalgam; all tooth surfaces except for dissected outsides were covered with blue wax. Then the teeth were immersed in 2% methylene blue dye for 48 hours. The amount of dye penetration into sagittal sections was measured by stereomicroscope at ×20 magnification by two independent observers who were blinded to the experiment. Data were statistically analyzed using student t-test. RESULTS: This study demonstrated that dye penetration was 0.8 mm (±0.53) in the lased and 0.97 mm (±0.54) in the non-lased group. It showed that, Er,Cr:YSGG laser can remove the debris and smear layer and consequently reduces the amount of dye penetration, although, the difference between the two groups was not statistically significant. CONCLUSION: This study showed that dye penetration was less in lased group because of the better seal of the dissected surface due to the better removal of the debris and smear layer by laser; further investigations are recommended in this field. [Iranian Endodontic Journal 2009;4(4):144-8] PMID:24019836

  16. Retrograde metasomatic effects on phase assemblages in an interlayered blueschist-greenschist sequence (Coastal Cordillera, Chile)

    NASA Astrophysics Data System (ADS)

    Halama, Ralf; Konrad-Schmolke, Matthias

    2015-02-01

    Interlayered blueschists and greenschists of the Coastal Cordillera (Chile) are part of a Late Palaeozoic accretionary complex. They represent metavolcanic rocks with oceanic affinities based on predominantly OIB-type REE patterns and immobile trace element ratios. Both rock types have similar mineralogies, albeit with different mineral modal abundances. Amphibole is the major mafic mineral and varies compositionally from glaucophane to actinolite. The presence of glaucophane relicts as cores in zoned amphiboles in both blueschists and greenschists is evidence for a pervasive high-pressure metamorphic stage, indicating that tectonic juxtaposition is an unlikely explanation for the cm-dm scale interlayering. During exhumation, a retrograde greenschist-facies overprint stabilized chlorite + albite + winchitic/actinolitic amphibole + phengitic white mica ± epidote ± K-feldspar at 0.4 ± 0.1 GPa. Geochemical variability can be partly ascribed to primary magmatic and partly to secondary metasomatic processes that occurred under greenschist-facies conditions. Isocon diagrams of several adjacent blueschist-greenschist pairs with similar protolith geochemistry were used to evaluate metasomatic changes due to retrograde fluid-rock interaction. The most important geochemical changes are depletion of Si and Na and addition of water in the greenschists compared to the blueschists. Transition metals and LILE are mobilized to varying degrees. The unsystematic deviations from magmatic fractionation trends suggest open system conditions and influx of an external fluid. Pseudosection and water isopleth calculations show that the rocks were dehydrating during most of their exhumation history and remained at water-saturated conditions. The mineralogical changes, in particular breakdown of blue amphibole and replacement by chlorite, albite and calcic/sodic-calcic amphibole, are the prime cause for the distinct coloring. Pseudo-binary phase diagrams were used as a means to link bulk

  17. Repair of Late Retrograde Type A Aortic Dissection After TEVAR: Causes and Management.

    PubMed

    Mosquera, Victor X; Marini, Milagros; Fraga-Manteiga, Daniel; Gulias, Daniel; Cuenca, Jose J

    2016-03-01

    One of the most feared complications of thoracic endovascular aortic repair (TEVAR) and hybrid arch repair is retrograde type A aortic dissection (RTAD). More than two-thirds of RTAD occurs in the immediate postoperative period and first postoperative month. In presentations beyond that point, progression of the native aortopathy must be considered. We report a late presentation of an RTAD seven months after hybrid repair of an aortic intramural hematoma with an ulcer-like projection, and review the causes and management of this TEVAR complication. © 2016 Wiley Periodicals, Inc.

  18. Using balloon-overtube-assisted enteroscopy for postoperative endoscopic retrograde cholangiopancreatography

    PubMed Central

    Skinner, Matthew; Velázquez-Aviña, Jacobo

    2014-01-01

    Endoscopic retrograde cholangiopancreatography (ERCP) is technically more challenging in patients with postsurgical anatomy such as Roux-en-Y anastomosis, frequently mandating an operative intervention. Although limited, there is growing evidence that ERCP can be performed using the balloon-overtube-assisted enteroscopy (BOAE) in patients with complex postoperative anatomy. We present the technical aspects of performing ERCP with the BOAE in patients presenting with complex postsurgical anatomy having biliary problems. ERCP using the BOAE is feasible in patients with complex postsurgical anatomy, permitting diagnostic and therapeutic interventions in 80% of patients. PMID:25364385

  19. Entrainment of sediment particles by retrograde vortices: Test of hypothesis using near-particle observations

    NASA Astrophysics Data System (ADS)

    Wu, Fu-Chun; Shih, Wu-Rong

    2012-09-01

    We conduct an experimental study to test the hypothesis that particle entrainment is associated with a passing retrograde vortex (spanwise vortex rotating counter to the mean shear). The pre- and post-entrainment quadrant structures are probed with the laser Doppler velocimetry (LDV) at a near-particle measurement spot, using the shifted-time cumulative quadrant fraction approach. The results are characterized by a pre-entrainment spiky rise of the Q1 fraction (outward interactions) and a mild increase of the Q4 fraction (sweeps), followed by the post-entrainment dominance of the Q4 fraction and a drastic drop of the Q1 fraction. Such results suggest that it is highly probable that particle entrainment is a result of the interactions with a passing retrograde-vortex-type coherent structure. The time series of 2-D velocities at the near-particle spot consistently exhibit the short-term peaks present at the time of entrainment. The quadrant signature at an alternative spot one grain diameter upstream of the target particle exhibits a sequence in which the pre-entrainment dominant Q1 fraction is replaced by the Q4 fraction, followed by a post-entrainment peak of the Q4 fraction. The results obtained from these two locations confirm the theoretical predictions, showing that different quadrant signatures would be detected at different spots during the passage of a retrograde vortex. We also perform an extra set of experiments, in which the target particle is set in an alternative pocket geometry with diagonal downstream valleys. The similar pre-entrainment quadrant signatures detected in all the experiments performed with different types of pocket geometry and the unique post-entrainment quadrant signature detected in those performed with the alternative pocket geometry imply that an obliquely oriented retrograde vortex may have passed, entraining the particle in diagonal directions. The results point to the potential discrepancy in the observed signatures that arises

  20. Endoscopic retrograde cholangiopancretography in modified double tracks anastomosis with anastomotic stenosis

    PubMed Central

    Wang, Xiao-Song; Wang, Fei; Li, Quan-Peng; Miao, Lin; Zhang, Xiu-Hua

    2017-01-01

    A 63-year-old man presented at our hospital with right upper abdomen pain and fever for 4 d. The patient’s magnetic resonance cholangiopancreatography revealed dilated common bile duct and choledocholithiasis. In his past history, he received proximal gastrectomy and modified double tracks anastomosis. Endoscopic retrograde cholangiopancretography in modified double tracks anastomosis, especially accompanied with anastomotic stenosis, has been rarely reported. In the present case, the duodenoscope was successfully introduced over the guidewire and the stone taken out using a basket. The patient had good palliation of his symptoms after removal of the stone. PMID:28360977

  1. Successful Angioplasty of Left Vertebral Artery and Right Subclavian Artery Via Retrograde Approach

    PubMed Central

    Namazi, Mohammad Hasan; Momenizadeh, Amir; Dousti, Amir; Naderian, Mohammadreza

    2017-01-01

    We describe a 77-year-old male who had right upper limb ischemic symptoms and history of unsuccessful right subclavian artery angioplasty. According to ultrasound findings, upper limb angiography was performed which confirmed stenosis of the left vertebral and right subclavian arteries. Percutaneous angioplasty and stenting of left vertebral and right subclavian arteries were performed in two separate sessions. Retrograde approach was scheduled for right subclavian artery angioplasty which is challenging due to potential risks to adjacent vertebral artery. This case reports underscores that percutaneous approaches may be preferential given their confirmed long-term efficacy and lower morbidity.

  2. Selective labeling of retinal ganglion cells with calcium indicators by retrograde loading in vitro

    PubMed Central

    Behrend, Matthew R.; Ahuja, Ashish K.; Humayun, Mark S.; Weiland, James D.; Chow, Robert H.

    2012-01-01

    Here we present a retrograde loading technique that makes it possible for the first time to rapidly load a calcium indicator in the majority of retinal ganglion cells (RGCs) in salamander retina, and then to observe physiological activity of these dye-loaded cells. Dextran-conjugated calcium indicator, dissolved in water, was applied to the optic nerve stump. Following dye loading, the isolated retina was mounted on a microelectrode array to demonstrate that electrical activity and calcium activity were preserved, as the retina responded to electrical stimuli. PMID:19428523

  3. A Class of Selenocentric Retrograde Orbits With Innovative Applications to Human Lunar Operations

    NASA Technical Reports Server (NTRS)

    Adamo, Daniel R.; Lester, Daniel F.; Thronson, Harley A.; Barbee, Brent

    2014-01-01

    Selenocentric distant retrograde orbits with radii from approx. 12,500 km to approx. 25,000 km are assessed for stability and for suitability as crewed command and control infrastructure locations in support of telerobotic lunar surface operations and interplanetary human transport. Such orbits enable consistent transits to and from Earth at virtually any time if they are coplanar with the Moon's geocentric orbit. They possess multiple attributes and applications distinct from NASA's proposed destination orbit for a redirected asteroid about 70,000 km from the Moon.

  4. A dispersive wave pattern on Jupiter's fastest retrograde jet at 20°S

    NASA Astrophysics Data System (ADS)

    Rogers, J. H.; Fletcher, L. N.; Adamoli, G.; Jacquesson, M.; Vedovato, M.; Orton, G. S.

    2016-10-01

    A compact wave pattern has been identified on Jupiter's fastest retrograding jet at 20°S (the SEBs) on the southern edge of the South Equatorial Belt. The wave has been identified in both reflected sunlight from amateur observations between 2010 and 2015, thermal infrared imaging from the Very Large Telescope and near infrared imaging from the Infrared Telescope Facility. The wave pattern is present when the SEB is relatively quiescent and lacking large-scale disturbances, and is particularly notable when the belt has undergone a fade (whitening). It is generally not present when the SEB exhibits its usual large-scale convective activity ('rifts'). Tracking of the wave pattern and associated white ovals on its southern edge over several epochs have permitted a measure of the dispersion relationship, showing a strong correlation between the phase speed (-43.2 to -21.2 m/s) and the longitudinal wavelength, which varied from 4.4 to 10.0° longitude over the course of the observations. Infrared imaging sensing low pressures in the upper troposphere suggest that the wave is confined to near the cloud tops. The wave is moving westward at a phase speed slower (i.e., less negative) than the peak retrograde wind speed (-62 m/s), and is therefore moving east with respect to the SEBs jet peak. Unlike the retrograde NEBn jet near °N, which is a location of strong vertical wind shear that sometimes hosts Rossby wave activity, the SEBs jet remains retrograde throughout the upper troposphere, suggesting the SEBs pattern cannot be interpreted as a classical Rossby wave. 2D windspeeds and thermal gradients measured by Cassini in 2000 are used to estimate the quasi-geostrophic potential vorticity gradient as a means of understanding the origin of the a wave. We find that the vorticity gradient is dominated by the baroclinic term and becomes negative (changes sign) in a region near the cloud-top level (400-700 mbar) associated with the SEBs. Such a sign reversal is a necessary (but

  5. Endovascular Treatment of Totally Occluded Superior Mesenteric Artery by Retrograde Crossing via the Villemin Arcade

    SciTech Connect

    Ferro, Carlo; Rossi, Umberto G. Seitun, Sara; Bovio, Giulio; Fornaro, Rosario

    2013-06-15

    Chronic mesenteric ischemia (CMI) is a rare disorder that is commonly caused by progressive atherosclerotic stenosis or occlusion of one or more mesenteric arteries. Endovascular treatment for symptomatic CMI represents a viable option, especially in high-operative risk patients. We report a case of acute symptomatic CMI with chronic totally occlusion of the superior mesenteric artery (SMA) associated with significant stenosis of celiac trunk (CT) and inferior mesenteric artery (IMA) that underwent endovascular treatment of all the three mesenteric arteries: stenting of CT and IMA stenosis, and recanalization of the SMA occlusion by retrograde crossing via the Villemin arcade.

  6. Application of Balloon-Occluded Retrograde Transvenous Obliteration to Gastric Varices Complicating Refractory Ascites

    SciTech Connect

    Fukuda, Tetsuya; Hirota, Shozo; Matsumoto, Shinichi; Sugimoto, Koji; Fujii, Masahiko; Tsurusaki, Masakatsu; Izaki, Kenta; Sugimura, Kazuro

    2004-01-15

    We report two cases of gastric varices complicated by massive ascites that disappeared after balloon-occluded retrograde transvenous obliteration (B-RTO). The first patient had progressive gastric varices that continued to enlarge even after three episodes of esophagogastric variceal bleeding, and the second patient was admitted to our hospital because of the bleeding from gastric varices. After B-RTO procedures in both patients, significant improvement of the ascites, hepatic function reserve, and hypoalbuminemia was observed. Although further experience is needed, our experience points to the likelihood of the amelioration of ascites after B-RTO.

  7. Pancreas imaging by computed tomography after endoscopic retrograde pancreatography. [Dogs; patients

    SciTech Connect

    Frick, M.P.; O'Leary, J.F.; Salomonowitz, E.; Stoltenberg, E.; Hutton, S.; Gedgaudas, E.

    1984-01-01

    A method using CT after endoscopic retrograde pancreatography (CT-ERP) is described for pancreatic imaging. When using an ERP technique in the canine model comparable to that used in humans, small amounts of contrast material in peripheral pancreatic radicles resulted in enhancement of the pancreas on CT scans. Nine patients were also studied by CT-ERP images. The main pancreatic duct was seen on delayed images. In cases of chronic pancreatitis (n = 2), pancreatic opacification was patchy and heterogeneous. There was no contrast-material enhancement in areas of pancreatic carcimomas (n = 2). CT-ERP showed the true extent of carcinoma better than ERP alone.

  8. Trends in endoscopic retrograde cholangiopancreatography in children within the United States, 2000-2009.

    PubMed

    Pant, Chaitanya; Sferra, Thomas J; Barth, Bradley A; Deshpande, Abhishek; Minocha, Anil; Qureshi, Waqar A; Olyaee, Mojtaba; Anderson, Michael P

    2014-07-01

    We investigated the volume of endoscopic retrograde cholangiopancreatographies (ERCPs) performed in hospitalized children in the United States using a nationwide healthcare administrative database for the years 2000 to 2009. A total of 22,153 cases of ERCP were identified: 6372 diagnostic and 17,314 therapeutic (1533 cases were recorded as undergoing both types during a single hospitalization). The number of ERCPs increased from 5337 to 6733 per year; diagnostic ERCPs decreased 43% and therapeutic increased 69% (significant decreasing trends for diagnostic and increasing for therapeutic ERCPs, P<0.001 for each analysis). Our results define a recent increase in the use of therapeutic ERCPs in hospitalized children.

  9. [A case of emphysematous pyelonephritis successfully treated by endotoxin absorption therapy and transurethral retrograde drainage].

    PubMed

    Tokuyama, Yoshiko; Fujita, Tetsuo; Hirayama, Takahiro; Matsushita, Kazuhito; Iwamura, Masatsugu; Baba, Shiro

    2009-07-01

    A 73-year-old male, who had undergone hormonal therapy due to stage D2 prostate cancer, complained of fever up and appetite loss. Abdominal computed tomography showed emphysematous pyelonephritis and right ureteral stone. At first, we could not perform any surgical treatment due to disseminated intravascular coagulation and septic shock. After endotoxin absorption therapy, we performed transurethral retrograde drainage, and successfully treated the emphysematous pyelonephritis. Endotoxin absorption therapy should be performed before surgical treatment in cases of emphysematous pyelonephritis with severe general condition.

  10. Role of Endoscopic Ultrasonography and Endoscopic Retrograde Cholangiopancreatography in the Clinical Assessment of Pancreatic Neoplasms.

    PubMed

    Varadarajulu, Shyam; Bang, Ji Young

    2016-04-01

    Accurate diagnosis and staging of pancreatic neoplasms is essential for surgical planning and identification of locally advanced and metastatic disease that is incurable by surgery. The ability to position the endoscopic ultrasonography (EUS) transducer close to the pancreas combined with the use of fine-needle aspiration enables the accurate diagnosis of pancreatic cysts and solid masses. EUS is also increasingly being used to procure core tissue for molecular analysis that facilitates personalized treatment of pancreatic cancer. Various therapeutic interventions can be undertaken under EUS guidance. This article focuses on the applications of EUS and endoscopic retrograde cholangiopancreatography in pancreatic neoplasms.

  11. Selective labeling of retinal ganglion cells with calcium indicators by retrograde loading in vitro.

    PubMed

    Behrend, Matthew R; Ahuja, Ashish K; Humayun, Mark S; Weiland, James D; Chow, Robert H

    2009-05-15

    Here we present a retrograde loading technique that makes it possible for the first time to rapidly load a calcium indicator in the majority of retinal ganglion cells (RGCs) in salamander retina, and then to observe physiological activity of these dye-loaded cells. Dextran-conjugated calcium indicator, dissolved in water, was applied to the optic nerve stump. Following dye loading, the isolated retina was mounted on a microelectrode array to demonstrate that electrical activity and calcium activity were preserved, as the retina responded to electrical stimuli.

  12. Subcapsular Renal-Infected Hematoma After Retrograde Intrarenal Surgery: A Rare but Serious Complication

    PubMed Central

    Consigliere, Lucas; Gallegos, Hector; Rojas, Francisco; Astroza, Gastón

    2016-01-01

    Abstract We report a case of a 53-year-old woman affected by a left kidney stone and persistent positive urinary culture treated by retrograde intrarenal surgery. During postoperative day 1, she developed a sudden back pain associated with a decrease in hemoglobin. CT scan showed a subcapsular hematoma giving the impression of partial compression of kidney and upper urinary tract. For that reason, in the first instance, a Double-J ureteral stent was installed. Unfortunately, an open surgical drainage was necessary because a secondary infection of the hematoma was evident during the following days. PMID:27579416

  13. FIP1/RCP Binding to Golgin-97 Regulates Retrograde Transport from Recycling Endosomes to the trans-Golgi Network

    PubMed Central

    Jing, Jian; Junutula, Jagath R.; Wu, Christine; Burden, Jemima; Matern, Hugo; Peden, Andrew A.

    2010-01-01

    Many proteins are retrieved to the trans-Golgi Network (TGN) from the endosomal system through several retrograde transport pathways to maintain the composition and function of the TGN. However, the molecular mechanisms involved in these distinct retrograde pathways remain to be fully understood. Here we have used fluorescence and electron microscopy as well as various functional transport assays to show that Rab11a/b and its binding protein FIP1/RCP are both required for the retrograde delivery of TGN38 and Shiga toxin from early/recycling endosomes to the TGN, but not for the retrieval of mannose-6-phosphate receptor from late endosomes. Furthermore, by proteomic analysis we identified Golgin-97 as a FIP1/RCP-binding protein. The FIP1/RCP-binding domain maps to the C-terminus of Golgin-97, adjacent to its GRIP domain. Binding of FIP1/RCP to Golgin-97 does not affect Golgin-97 recruitment to the TGN, but appears to regulate the targeting of retrograde transport vesicles to the TGN. Thus, we propose that FIP1/RCP binding to Golgin-97 is required for tethering and fusion of recycling endosome-derived retrograde transport vesicles to the TGN. PMID:20610657

  14. FIP1/RCP binding to Golgin-97 regulates retrograde transport from recycling endosomes to the trans-Golgi network.

    PubMed

    Jing, Jian; Junutula, Jagath R; Wu, Christine; Burden, Jemima; Matern, Hugo; Peden, Andrew A; Prekeris, Rytis

    2010-09-01

    Many proteins are retrieved to the trans-Golgi Network (TGN) from the endosomal system through several retrograde transport pathways to maintain the composition and function of the TGN. However, the molecular mechanisms involved in these distinct retrograde pathways remain to be fully understood. Here we have used fluorescence and electron microscopy as well as various functional transport assays to show that Rab11a/b and its binding protein FIP1/RCP are both required for the retrograde delivery of TGN38 and Shiga toxin from early/recycling endosomes to the TGN, but not for the retrieval of mannose-6-phosphate receptor from late endosomes. Furthermore, by proteomic analysis we identified Golgin-97 as a FIP1/RCP-binding protein. The FIP1/RCP-binding domain maps to the C-terminus of Golgin-97, adjacent to its GRIP domain. Binding of FIP1/RCP to Golgin-97 does not affect Golgin-97 recruitment to the TGN, but appears to regulate the targeting of retrograde transport vesicles to the TGN. Thus, we propose that FIP1/RCP binding to Golgin-97 is required for tethering and fusion of recycling endosome-derived retrograde transport vesicles to the TGN.

  15. Apical/Retrograde Periimplantitis/Implant Periapical Lesion: Etiology, Risk Factors, and Treatment Options: A Systematic Review.

    PubMed

    Ramanauskaite, Ausra; Juodzbalys, Gintaras; Tözüm, Tolga F

    2016-10-01

    To review the literature on retrograde periimplantitis symptoms, risk factors, and treatment methods and to propose a decision-making tree of retrograde periimplantitis management. An electronic literature search was conducted on the MEDLINE and EMBASE databases for articles published between 1990 and 2015. Clinical human studies in the English language were included. The search resulted in 44 case reports published by 27 authors. The average time of the diagnosis of the pathology was found to be 26.07 weeks after implant placement (SD ± 39.7). Fistula formation was found to be the most common clinical symptom, statistically significantly more often occurring in the maxilla (P = 0.04). A negative correlation was found between pain and the adjacent tooth with incomplete endodontic treatment/endodontic pathology (r = -0.4; P = 0.009) and a positive correlation between the later risk factor and implant removal (r = 0.3; P = 0.028). Regenerative treatment (45.2% of the cases) or implant removal (35.7% of the cases) was the most common treatment techniques used. A decision-making tree of retrograde periimplantitis management is suggested. The etiology of retrograde periimplantitis is most often infectious. A decision-making tree aimed at managing patients with retrograde periimplantitis according to the possible etiology and symptoms of the disease can be a useful tool in the treatment of the pathology.

  16. Glucocorticoids Regulate Glutamate and GABA Synapse-Specific Retrograde Transmission via Divergent Non-Genomic Signaling Pathways

    PubMed Central

    Di, Shi; Maxson, Marc M.; Franco, Alier; Tasker, Jeffrey G.

    2009-01-01

    Glucocorticoids exert an opposing rapid regulation of glutamate and GABA synaptic inputs to hypothalamic magnocellular neurons via the activation of postsynaptic membrane-associated receptors and the release of retrograde messengers. Glucocorticoids suppress synaptic glutamate release via the retrograde release of endocannabinoids and facilitate synaptic GABA release via an unknown retrograde messenger. Here, we show that the glucocorticoid facilitation of GABA inputs is due to the retrograde release of neuronal nitric oxide, and that glucocorticoid-induced endocannabinoid synthesis and nitric oxide synthesis are mediated by divergent G protein signaling mechanisms. While the glucocorticoid-induced, endocannabinoid-mediated suppression of glutamate release is dependent on activation of the Gαs G protein subunit and cAMP-PKA activation, the nitric oxide facilitation of GABA release is mediated by Gβγ signaling that leads to activation of neuronal nitric oxide synthase. Our findings indicate, therefore, that glucocorticoids exert opposing rapid actions on glutamate and GABA release by activating divergent G protein signaling pathways that trigger the synthesis of, and glutamate and GABA synapse-specific retrograde actions of, endocannabinoids and nitric oxide, respectively. The simultaneous rapid stimulation of nitric oxide and endocannabinoid synthesis by glucocorticoids has important implications for the impact of stress on the brain as well as on neural-immune interactions in the hypothalamus. PMID:19144839

  17. Retrograde ejaculation

    MedlinePlus

    ... AJ, Kavoussi LR, Partin AW, Peters CA, eds. Campbell-Walsh Urology . 11th ed. Philadelphia, PA: Elsevier; 2016: ... AJ, Kavoussi LR, Partin AW, Peters CA, eds. Campbell-Walsh Urology . 11th ed. Philadelphia, PA: Elsevier; 2016: ...

  18. Retrograde cystography

    MedlinePlus

    ... Campbell-Walsh Urology . 10th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 4. Read More Bladder stones Blood clots Diverticulitis Reflux nephropathy Urinary tract infection - adults X-ray Review Date 1/21/2015 Updated by: Scott Miller, MD, urologist in private practice in Atlanta, ...

  19. NEXT GENERATION OF TELESCOPES OR DYNAMICS REQUIRED TO DETERMINE IF EXO-MOONS HAVE PROGRADE OR RETROGRADE ORBITS

    SciTech Connect

    Lewis, Karen M.; Fujii, Yuka

    2014-08-20

    We survey the methods proposed in the literature for detecting moons of extrasolar planets in terms of their ability to distinguish between prograde and retrograde moon orbits, an important tracer of the moon formation channel. We find that most moon detection methods, in particular, sensitive methods for detecting moons of transiting planets, cannot observationally distinguishing prograde and retrograde moon orbits. The prograde and retrograde cases can only be distinguished where the dynamical evolution of the orbit due to, e.g., three body effects is detectable, where one of the two cases is dynamically unstable, or where new observational facilities, which can implement a technique capable of differentiating the two cases, come online. In particular, directly imaged planets are promising targets because repeated spectral and photometric measurements, which are required to determine moon orbit direction, could also be conducted with the primary interest of characterizing the planet itself.

  20. The microRNA miR-1 regulates a MEF-2-dependent retrograde signal at neuromuscular junctions.

    PubMed

    Simon, David J; Madison, Jon M; Conery, Annie L; Thompson-Peer, Katherine L; Soskis, Michael; Ruvkun, Gary B; Kaplan, Joshua M; Kim, John K

    2008-05-30

    We show that miR-1, a conserved muscle-specific microRNA, regulates aspects of both pre- and postsynaptic function at C. elegans neuromuscular junctions. miR-1 regulates the expression level of two nicotinic acetylcholine receptor (nAChR) subunits (UNC-29 and UNC-63), thereby altering muscle sensitivity to acetylcholine (ACh). miR-1 also regulates the muscle transcription factor MEF-2, which results in altered presynaptic ACh secretion, suggesting that MEF-2 activity in muscles controls a retrograde signal. The effect of the MEF-2-dependent retrograde signal on secretion is mediated by the synaptic vesicle protein RAB-3. Finally, acute activation of levamisole-sensitive nAChRs stimulates MEF-2-dependent transcriptional responses and induces the MEF-2-dependent retrograde signal. We propose that miR-1 refines synaptic function by coupling changes in muscle activity to changes in presynaptic function.

  1. Retrograde axonal transport of LIF is increased by peripheral nerve injury: correlation with increased LIF expression in distal nerve.

    PubMed

    Curtis, R; Scherer, S S; Somogyi, R; Adryan, K M; Ip, N Y; Zhu, Y; Lindsay, R M; DiStefano, P S

    1994-01-01

    Leukemia inhibitory factor (LIF) is a cytokine that affects the survival and differentiation of certain neuronal populations in vitro. To identify LIF-responsive neurons in the adult rat, we have demonstrated retrograde axonal transport of 125I-LIF to sensory and motor neurons. The accumulation of 125I-LIF by both cell types was significantly increased by prior sciatic nerve crush. Retrograde transport of 125I-LIF was inhibited by excess unlabeled LIF but not by related cytokines, indicating a specific receptor-mediated mechanism. Northern blot analysis revealed LIF expression in peripheral nerve that was increased in distal segments after axotomy. The correlation between LIF expression and increased retrograde transport following injury suggests that LIF plays a role in peripheral nerve regeneration.

  2. Differential role of the low affinity neurotrophin receptor (p75) in retrograde axonal transport of the neurotrophins.

    PubMed

    Curtis, R; Adryan, K M; Stark, J L; Park, J S; Compton, D L; Weskamp, G; Huber, L J; Chao, M V; Jaenisch, R; Lee, K F

    1995-06-01

    The receptor mechanisms mediating the retrograde axonal transport of the neurotrophins have been investigated in adult rats. We show that transport of the TrkB ligands NT-4 and BDNF to peripheral neurons is dependent on the low affinity neurotrophin receptor (LNR). Pharmacological manipulation of LNR in vivo using either an anti-LNR antibody or a soluble recombinant LNR extracellular domain completely blocked retrograde transport of NT-4 and BDNF to sensory neurons, while having minimal effects on the transport of NGF in either sensory or sympathetic neurons. Furthermore, in mice with a null mutation of LNR, the transport of NT-4 and BDNF, but not NGF, was dramatically reduced. These observations demonstrate a selective role for LNR in retrograde transport of the various neurotrophins from distinct target regions in vivo.

  3. Retrograde entry portal for femoral interlocking nailing in femoral nonunion after plate failure: a prospective comparative study with antergrade portal.

    PubMed

    Assaghir, Yasser

    2017-03-01

    The piriformis fossa is the ideal portal of entry for antegrade interlocking nailing. Localizing this portal can be difficult and its eccentricity leads to complications. This prospective comparative study was designed to compare an innovative way to obtain the ideal portal from inside the medullary canal in cases of plate failure and compare it to the classic antegrade portal. It included 41 cases (19 antegrade and 22 retrograde). The retrograde portal was significantly better in terms of entry time, radiation time, blood-loss, and wound length. The proper portal was rapidly and easily achieved in all retrograde cases without complications; while four in antegrade cases had complications. Minimum follow-up was 2 years. Level of evidence III.

  4. Retrograde Approach is as Effective and Safe as Antegrade Approach in Contemporary Percutaneous Coronary Intervention for Chronic Total Occlusion: A Taiwan Single-Center Registry Study

    PubMed Central

    Lee, Chih-Kuo; Chen, Ying-Hsien; Lin, Mao-Shin; Yeh, Chih-Fan; Hung, Chi-Sheng; Kao, Hsien-Li; Huang, Ching-Chang

    2017-01-01

    Background In percutaneous coronary intervention (PCI) for chronic total occlusion (CTO), most experts regard the antegrade approach as the default initial strategy, reserving the retrograde approach for reattempts following antegrade failure. In this study, we aimed to compare the efficacy and safety between the antegrade and retrograde approaches in CTO PCI. Results Between 2012 and 2013, patients that underwent 321 consecutive attempts by high-volume operators (> 75 total CTO PCI cases during the period) in a tertiary university-affiliated hospital were enrolled. The antegrade approach was used in 152 patients, and retrograde in 169 patients. The duration of occlusion was significantly longer and the J-CTO score higher in the retrograde group. Technical success was achieved in 148 patients of the antegrade group (97.4%), and 163 patients in the retrograde group (96.4%) (p = 0.75). A major procedural complication occurred in 3 patients of the antegrade group (2.0%) and in 6 patients of the retrograde group (3.6%) (p = 0.51). In-hospital major adverse cardiac events (MACE) rates (antegrade 0.7%, n = 152; retrograde 0.6%, n = 169) were comparable. The procedure and fluoroscopy times were significantly longer, with more radiation exposure and contrast medium consumption, in the retrograde group. In the retrograde group, similar success, procedural complication and in-hospital MACE rates were achieved in the 3 collateral subgroups. Conclusions In selected cases and with highly experienced operators, retrograde approach in CTO PCI is as effective and safe as antegrade approach at the expense of longer procedure time, more radiation exposure and contrast medium consumption. For retrograde approach, either septal, epicardial or AV groove collaterals can be used with similarly success, complication and in-hospital MACE rates. PMID:28115803

  5. Studies suggest alternatives to amalgam as a retrograde filling material for apicectomy.

    PubMed

    Naito, Toru

    2004-01-01

    Sources were Medline and the Cochrane Library. Studies included were in vivo with human subjects, had experimental and control groups, and gave quantitative results in English, German or French. Success and failure rates were derived from randomised controlled trials (RCT), clinical controlled trials (CCT), cohort studies (CS) and case-controlled studies (CCS). Qualitative synthesis of results was performed. Two RCT, six CCT and 14 CCS were identified. The two RCT suggest that glass ionomer may be more effective than amalgam, conversely one CCT showed amalgam to be more effective. CCTs also suggest that EBA (reinforced zinc oxide eugenol) cement, composite with GLUMA (Bayer AG., Leverkusen, Germany) and gold leaf retrograde filling may be more effective than amalgam. A further CCT suggested that gutta-percha used as a retrograde filing is less effective than when used following an orthograde approach. Based on the outcome of two RCT, glass ionomer appears as effective as amalgam. EBA cement, composite with GLUMA and gold leaf and orthograde gutta-percha may also be as effective as amalgam. Evidence is limited, however, and further research is needed.

  6. Tibiotalocalcaneal arthrodesis with retrograde intramedullary nailing: 29 patients’ clinical and functional evaluation☆☆☆

    PubMed Central

    Caixeta, Thiago Barbosa; Júnior, Márcio Oliveira Calábria; de Castro, Régis Vieira; Martins, Jefferson Soares; Costa, Edegmar Nunes; Albieri, Alexandre Daher; de Moraes, Frederico Barra

    2014-01-01

    Objective To evaluate clinically and functionally the pos-operative results of patients submitted to tibiotalocalcaneal arthrodesis for the treatment of traumatic arthropathy and neuropathy. Methods Retrospective study of 29 patients undergoing ankle arthrodesis with intramedullary retrograde nail. All patients were evaluated for fusion time, AOFAS and VAS scores, satisfaction, and complications of surgery. The mean follow-up was 36 months (range 6–60 months). Results The union rate was 82%, and the consolidation occurred on average at 16 weeks (10–24 weeks). The pos-operative AOFAS score improved in 65.5% (average of 57.7 on neurological cases and 75.7 on cases pos-traumatic) and VAS score improved 94.1% (average of 2.3 on neurological cases and 4,2 on post-traumatic cases), and 86% of patients were satisfied with the procedure performed. Complications occurred in 11 patients (38%), including pseudoarthrosis (17.24%), infection (17.24%), material failure (13.8%) and fracture (13.8%). Conclusion Tibiotalocalcaneal arthrodesis with retrograde intramedullary nail proved to be a good option for saving the ankle joint, with improvement of clinical and functional scores (AOFAS = 65.5% and VAS = 94.1%). PMID:26229773

  7. Proneurotrophin-3 is a neuronal apoptotic ligand: evidence for retrograde-directed cell killing

    PubMed Central

    Yano, Hiroko; Torkin, Risa; Martin, Laura Andrés; Chao, Moses V.; Teng, Kenneth K.

    2010-01-01

    While mature neurotrophins are well-described trophic factors that elicit retrograde survival signaling, the precursor forms of neurotrophins (i.e., proneurotrophins) can function as high affinity apoptotic ligands for selected neural populations. An outstanding question is whether target-derived proneurotrophins might affect neuronal survival/death decisions through a retrograde transport mechanism. Since neurotrophin-3 (NT-3) is highly expressed in non-neural tissues that receive peripheral innervation, we investigated the localized actions of its precursor (proNT-3) on sympathetic neurons in the present study. Pharmacological inhibition of intracellular furin proteinase activity in 293T cells resulted in proNT-3 release instead of mature NT-3 while membrane depolarization in cerebellar granule neurons stimulated endogenous proNT-3 secretion, suggesting that proNT-3 is an inducible bona fide ligand in the nervous system. Our data also indicate that recombinant proNT-3 induced sympathetic neuron death that is p75NTR- and sortilin-dependent, with hallmark features of apoptosis including JNK activation and nuclear fragmentation. Using compartmentalized culture systems that segregate neuronal cell bodies from axons, proNT-3, acting within the distal axon compartment, elicited sympathetic neuron death and overrode the survival promoting actions of NGF. Together these results raise the intriguing possibility that dysregulation of proneurotrophin processing/release by innervated targets can be deleterious to the neurons projecting to these sites. PMID:19940174

  8. Anatomical study of the ulnar dorsal artery and design of a new retrograde ulnar dorsal flap.

    PubMed

    Vergara-Amador, Enrique

    2008-05-01

    The purpose of this article is to describe a new flap that resulted from a study of the vascular distribution of the ulnar dorsal artery. The study was directed toward the distal and proximal branches with their anastomoses. Green latex was injected into the brachial artery of the proximal limbs of 25 cadavers. After 48 hours, dissection of the vessels was performed beginning at the ulnar dorsal artery and following its descending and ascending branches. In two of the specimens, an injection of methylene blue was administered in the ulnar artery to look for reverse flow from the descending branch. The ulnar dorsal artery was located in all injected limbs with a constant distribution. It had two branches: a descending one that distributed under the abductor digiti quinti muscle and anastomosed with a deep branch of the ulnar artery, and an ascending one supplying the proximal third of the forearm. Retrograde flow in the descending branch was found by injecting dye. Based on these findings, a flap with reverse flow that the author called a "retrograde ulnar dorsal flap" was designed at the expense of the descending branch by ligating the ulnar dorsal artery where it originates. This makes it possible to cover soft-tissue defects that are more distal on the hand.

  9. Semaphorin 3A is a retrograde cell death signal in developing sympathetic neurons

    PubMed Central

    Wehner, Amanda B.; Abdesselem, Houari; Dickendesher, Travis L.; Imai, Fumiyasu; Yoshida, Yutaka; Giger, Roman J.; Pierchala, Brian A.

    2016-01-01

    ABSTRACT During development of the peripheral nervous system, excess neurons are generated, most of which will be lost by programmed cell death due to a limited supply of neurotrophic factors from their targets. Other environmental factors, such as ‘competition factors' produced by neurons themselves, and axon guidance molecules have also been implicated in developmental cell death. Semaphorin 3A (Sema3A), in addition to its function as a chemorepulsive guidance cue, can also induce death of sensory neurons in vitro. The extent to which Sema3A regulates developmental cell death in vivo, however, is debated. We show that in compartmentalized cultures of rat sympathetic neurons, a Sema3A-initiated apoptosis signal is retrogradely transported from axon terminals to cell bodies to induce cell death. Sema3A-mediated apoptosis utilizes the extrinsic pathway and requires both neuropilin 1 and plexin A3. Sema3A is not retrogradely transported in older, survival factor-independent sympathetic neurons, and is much less effective at inducing apoptosis in these neurons. Importantly, deletion of either neuropilin 1 or plexin A3 significantly reduces developmental cell death in the superior cervical ganglia. Taken together, a Sema3A-initiated apoptotic signaling complex regulates the apoptosis of sympathetic neurons during the period of naturally occurring cell death. PMID:27143756

  10. Pilot study of endoscopic retrograde 3-dimensional - computed tomography enteroclysis for the assessment of Crohn's disease.

    PubMed

    Tanabe, Hiroki; Ito, Takahiro; Inaba, Yuhei; Ando, Katsuyoshi; Nomura, Yoshiki; Ueno, Nobuhiro; Kashima, Shin; Moriichi, Kentaro; Fujiya, Mikihiro; Okumura, Toshikatsu

    2017-01-01

    Endoscopic retrograde ileography (ERIG) is developed in our institute and applied clinically for the diagnosis and assessment of the Crohn's disease activity. We have further improved the technique using 3-dimensional - computed tomography enteroclysis (3D-CTE) and conducted a retrospective study to determine the feasibility and the diagnostic value of endoscopic retrograde 3D-CTE (ER 3D-CTE) in Crohn's disease patients in a state of remission. Thirteen Crohn's patients were included in this pilot study. CTE was performed after the infusion of air or CO2 through the balloon tube following conventional colonoscopy. The primary endpoint of this study was to assess the safety of this method. Secondarily, the specific findings of Crohn's disease and length of the visualized small intestine were assessed. The procedures were completed without any adverse events. Gas passed through the small intestine and enterographic images were obtained in 10 out of 13 cases, but, in the remaining patients, insertion of the balloon tubes into the terminal ileum failed. Various features specific to Crohn's disease were visualized using ER 3D-CTE. A cobble stone appearance or hammock-like malformation was specific and effective for diagnosing Crohn's disease and the features of anastomosis after the surgical operations were also well described. Therefore, this technique may be useful after surgery. In this study, ER 3D-CTE was performed safely in Crohn's disease patients and may be used for the diagnosis and follow-up of this disease.

  11. Impaired retrograde transport of axonal autophagosomes contributes to autophagic stress in Alzheimer’s disease neurons

    PubMed Central

    Tammineni, Prasad; Ye, Xuan; Feng, Tuancheng; Aikal, Daniyal; Cai, Qian

    2017-01-01

    Neurons face unique challenges of transporting nascent autophagic vacuoles (AVs) from distal axons toward the soma, where mature lysosomes are mainly located. Autophagy defects have been linked to Alzheimer’s disease (AD). However, the mechanisms underlying altered autophagy remain unknown. Here, we demonstrate that defective retrograde transport contributes to autophagic stress in AD axons. Amphisomes predominantly accumulate at axonal terminals of mutant hAPP mice and AD patient brains. Amyloid-β (Aβ) oligomers associate with AVs in AD axons and interact with dynein motors. This interaction impairs dynein recruitment to amphisomes through competitive interruption of dynein-Snapin motor-adaptor coupling, thus immobilizing them in distal axons. Consistently, deletion of Snapin in mice causes AD-like axonal autophagic stress, whereas overexpressing Snapin in hAPP neurons reduces autophagic accumulation at presynaptic terminals by enhancing AV retrograde transport. Altogether, our study provides new mechanistic insight into AD-associated autophagic stress, thus establishing a foundation for ameliorating axonal pathology in AD. DOI: http://dx.doi.org/10.7554/eLife.21776.001 PMID:28085665

  12. Distant Retrograde Orbits for space-based Near Earth Objects detection

    NASA Astrophysics Data System (ADS)

    Stramacchia, Michele; Colombo, Camilla; Bernelli-Zazzera, Franco

    2016-09-01

    We analyse a concept for the detection of Potentially Hazardous Asteroids (PHAs) from a space-based network of telescopes on retrograde Distant Periodic Orbits. Planar periodic orbits are designed in the Sun-Earth circular restricted three-body problem, starting from initial conditions in the Hill's problem available from the literature. A family of retrograde orbits centred at the Earth is selected as baseline, based on their maximum distance from Earth, larger than the Earth-L2 distance. Indeed, spacecraft on such orbits can detect PHAs incoming from the Sun direction, which could not otherwise be monitored from current Earth-based systems. A trade-off on the orbit amplitude, asteroid diameter to be detected, and the constellation size is performed considering current visible sensor telescope technology. The Chelyabinsk meteor scenario is studied and the potential warning time that could be gained with a space-based survey system with respect to an Earth based-survey system is shown.

  13. An experimental study of retrograde axonal plasmatic flow in the peripheral nerves of rats.

    PubMed

    Sanguinetti, C; Tranquilli Leali, P; Grispigni, C

    1986-12-01

    Retrograde axonal flow (R.A.F.) in the sciatic nerve of Sprague Dowley rats was studied by injecting horseradish peroxidase (H.R.P.) peripherally and identifying its appearance in the related segment of the spinal cord. This called for a precise identification of the vertebro-medullary topography, the afferant root levels of the sciatic nerve, and the transport velocity of the H.R.P. Our study revealed a clear difference of neuromuscular end plate permeability as between new-born and adult animals. The vertebral column of the rat consists of 8 cervical metameres, 13 dorsal, 6 lumbar, 4 sacral, and 3 coccygeal. The sciatic nerve is derived principally from the roots L4, L5, L6 and in part from L3 and S1. The injection of H.R.P. in the sural triceps of the new-born rat produced granules in the anterior horn cells as early as 12 hours later. In similar experiments with adult rats H.R.P. in the motorneurons was never detected. In our experimental model the transport velocity of H.R.P. from the point of injection to the anterior horn cells was approximately 68 mm per day. These findings provide a foundation on which to base future studies of retrograde flows in conditions of induced pathology.

  14. Retrograde transport of KDEL-bearing B-fragment of Shiga toxin.

    PubMed

    Johannes, L; Tenza, D; Antony, C; Goud, B

    1997-08-01

    To investigate retrograde transport along the biosynthetic/secretory pathway, we have constructed a recombinant Shiga toxin B-fragment carrying an N-glycosylation site and a KDEL retrieval motif at its carboxyl terminus (B-Glyc-KDEL). After incubation with HeLa cells, B-Glyc-KDEL was progressively glycosylated in the endoplasmic reticulum (ER) and remained stably associated with this compartment. B-fragment with a nonfunctional KDEL sequence (B-Glyc-KDELGL) was glycosylated with about the same kinetics as B-Glyc-KDEL but localized at steady state to the Golgi apparatus. Morphological studies showed that B-Glyc-KDEL was delivered from the plasma membrane, via endosomes and the cisternae of the Golgi apparatus, to the ER. Moreover, the addition of a sulfation site allowed us to show that B-Glyc-KDEL on transit to the ER entered the Golgi apparatus through the trans-Golgi network. Transport of B-Glyc-KDEL to the ER was slowed down by nocodazole, indicating that microtubules are important for the retrograde pathway. Our results document the existence of a continuous pathway from the plasma membrane to the endoplasmic reticulum via the Golgi apparatus and show that a fully folded exogenous protein arriving in the endoplasmic reticulum via this pathway can undergo N-glycosylation.

  15. Effect of Retrograde Reaming for Tibiotalocalcaneal Arthrodesis on Subtalar Joint Destruction: A Cadaveric Study.

    PubMed

    Lowe, Jason A; Routh, Lucas K; Leary, Jeffrey T; Buzhardt, Paul C

    2016-01-01

    Recent published data have suggested successful union of subtalar and tibiotalar joints without formal debridement during tibiotalocalcaneal (TTC) fusion procedures. Although previous studies have reported on the importance of the proper guidewire starting point and trajectory to obtain appropriate hindfoot alignment for successful fusion, to our knowledge, no studies have quantified the amount of articular damage to the subtalar joint with retrograde reaming. We hypothesized that reaming would destroy >50% of the posterior facet of the subtalar joint. The bilateral lower extremities of 5 cadavers were obtained and the subtalar joints exposed. Retrograde TTC nail guidewires were inserted, and a 12-mm reamer was passed through the subtalar and ankle joints. Pre- and postreaming images of the subtalar joint were obtained to compare the amount of joint destruction after reaming. We found an average of 5.89% articular destruction of the talar posterior facet and an average of 4.01% articular destruction of the posterior facet of the calcaneus. No damage to the middle facets of the subtalar joint was observed. TTC nailing is a successful procedure for ankle and subtalar joint fusion. Published studies have reported successful subtalar union using TTC nailing without formal open debridement of the subtalar joint, preserving the soft tissue envelope. TTC nail insertion using a 12-mm reamer will destroy 5.89% and 4.01% of the respective talar and calcaneal posterior facets of the subtalar joint.

  16. Gelatinization and retrogradation phenomena in starch/montmorillonite nanocomposites plasticized with different glycerol/water ratios.

    PubMed

    Lara, Sandra Camila; Salcedo, Felipe

    2016-10-20

    This study aims to gain insights into the intermolecular interactions present in thermoplastic starch (TPS)/montmorillonite (MMT) nanocomposites prepared using water and/or glycerol as plasticizers. Specifically, the impact of using different glycerol/water proportions on the nature of gelatinization and retrogradation processes is studied. Nanocomposites were characterized by rheometry, scanning electron microscopy (SEM) and X-rays diffraction (XRD). It is shown that clay tactoids preferentially interact with glycerol molecules rather than starch macromolecules. Consequently, the effects of MMT incorporation strongly depend on the glycerol/water ratio; when a ratio of 0.5 is used minor variations were observed on the starch gelatinization process-although stronger clays-starch interactions were evident-whereas at higher ratios the addition of clays significantly increased the gelatinization temperature, up to values over 100°C. In the gelatinization process of starch in TPS samples having only glycerol as a plasticizer, the leaching of amylose and the melting of amylopectin crystalline domains seem to occur simultaneously. This different gelatinization mechanism produces a TPS having a substantially different morphology, which exhibited reduced retrogradation characteristics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. The retrograde orbit of the HAT-P-6b exoplanet

    NASA Astrophysics Data System (ADS)

    Hébrard, G.; Ehrenreich, D.; Bouchy, F.; Delfosse, X.; Moutou, C.; Arnold, L.; Boisse, I.; Bonfils, X.; Díaz, R. F.; Eggenberger, A.; Forveille, T.; Lagrange, A.-M.; Lovis, C.; Pepe, F.; Perrier, C.; Queloz, D.; Santerne, A.; Santos, N. C.; Ségransan, D.; Udry, S.; Vidal-Madjar, A.

    2011-03-01

    We observed the transit of the HAT-P-6b exoplanet across its host star with the SOPHIE spectrograph (OHP, France). The resulting stellar radial velocities display the Rossiter-McLaughlin anomaly and reveal a retrograde orbit: the planetary orbital spin and the stellar rotational spin point in approximately opposite directions. A fit to the anomaly measures a sky-projected angle λ = 166° ± 10° between these two spin axes. All seven known retrograde planets are hot Jupiters with masses Mp < 3 MJup. About two thirds of the planets in this mass range, however, are prograde and aligned (λ ≃ 0°). In contrast, most of the more massive planets (Mp > 4 MJup) are prograde but misaligned. Different mechanisms may therefore be responsible for planetary obliquities above and below ~3.5 MJup. Based on observations collected with the SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS), France, by the SOPHIE Consortium (program 10A.PNP.CONS).SOPHIE radial velocities are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/527/L11

  18. Endoscopic and retrograde cholangiographic appearance of hepaticojejunostomy strictures: A practical classification

    PubMed Central

    Mönkemüller, Klaus; Jovanovic, Ivan

    2011-01-01

    AIM: To study the endoscopic and radiological characteristics of patients with hepaticojejunostomy (HJ) and propose a practical HJ stricture classification. METHODS: In a retrospective observational study, a balloon-assisted enteroscopy (BAE)-endoscopic retrograde cholangiography was performed 44 times in 32 patients with surgically-altered gastrointestinal (GI) anatomy. BAE-endoscopic retrograde cholangio pancreatography (ERCP) was performed 23 times in 18 patients with HJ. The HJ was carefully studied with the endoscope and using cholangiography. RESULTS: The authors observed that the hepaticojejunostomies have characteristics that may allow these to be classified based on endoscopic and cholangiographic appearances: the HJ orifice aspect may appear as small (type A) or large (type B) and the stricture may be short (type 1), long (type 2) and type 3, intrahepatic biliary strictures not associated with anastomotic stenosis. In total, 7 patients had type A1, 4 patients A2, one patient had B1, one patient had B (large orifice without stenosis) and one patient had type B3. CONCLUSION: This practical classification allows for an accurate initial assessment of the HJ, thus potentially allowing for adequate therapeutic planning, as the shape, length and complexity of the HJ and biliary tree choice may mandate the type of diagnostic and therapeutic accessories to be used. Of additional importance, a standardized classification may allow for better comparison of studies of patients undergoing BAE-ERCP in the setting of altered upper GI anatomy. PMID:22110837

  19. Episodic future thinking and future-based decision-making in a case of retrograde amnesia.

    PubMed

    De Luca, Flavia; Benuzzi, Francesca; Bertossi, Elena; Braghittoni, Davide; di Pellegrino, Giuseppe; Ciaramelli, Elisa

    2017-08-09

    We investigated episodic future thinking (EFT) and future-based cognition and decision-making in patient SG, who developed a dense retrograde amnesia following hypoxia due to a cardiac arrest. Despite intact general cognitive and executive functioning, SG was unable to remember events from his entire lifetime. He had, however, relatively spared anterograde memory and general semantic knowledge. Voxel-based morphometry detected a reduction of gray matter in the thalamus, cerebellum and fusiform gyrus bilaterally, and, at a reduced threshold, in several regions of the autobiographical memory network, including the hippocampi. We show that SG is unable to imagine personal future events, but can imagine fictitious events not self-relevant and not located in subjective time. Despite severely impaired EFT, SG shows normal attitudes towards the future time, and normal delay discounting rates. These findings suggest that retrieval of autobiographical information from long-term memory is necessary for EFT. However, relatively spared anterograde memory and general semantic knowledge may be sufficient to allow construction of fictitious experiences. As well, EFT is not necessary to drive future-oriented cognition and choice. These findings highlight the relation between autobiographical memory and EFT, and the fractionation of human temporal consciousness. Moreover, they contribute to our understanding of retrograde amnesia as an impairment of memory as well as future thinking. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Structurally optimized analogs of the retrograde trafficking inhibitor Retro-2cycl limit Leishmania infections.

    PubMed

    Craig, Evan; Huyghues-Despointes, Charles-Eugene; Yu, Chun; Handy, Emma L; Sello, Jason K; Kima, Peter E

    2017-05-01

    In infected mammalian cells, Leishmania parasites reside within specialized compartments called parasitophorous vacuoles (LPVs). We have previously shown that Retro-2, a member of a novel class of small retrograde pathway inhibitors caused reduced LPV sizes and lower parasite numbers during experimental L. mexicana sp. infections. The purpose of this study was to determine if structural analogs of Retro-2cycl reported to have superior potency in the inhibition of retrograde pathway-dependent phenomena (i.e., polyomavirus cellular infection by polyomavrius and Shiga toxin trafficking in cells) are also more effective than the parent compound at controlling Leishmania infections. In addition to their effects on LPV development, we show that two optimized analogs of Retro-2cycl, DHQZ 36 and DHQZ 36.1 limit Leishmania amazonensis infection in macrophages at EC50 of 13.63+/-2.58μM and10.57+/-2.66μM, respectively, which is significantly lower than 40.15μM the EC50 of Retro-2cycl. In addition, these analogs caused a reversal in Leishmania induced suppression of IL-6 release by infected cells after LPS activation. Moreover, we show that in contrast to Retro-2cycl that is Leishmania static, the analogs can kill Leishmania parasites in axenic cultures, which is a desirable attribute for any drug to treat Leishmania infections. Together, these studies validate and extend the published structure-activity relationship analyses of Retro-2cycl.

  1. New tetrasilicate cements as retrograde filling material: an in vitro study on fluid penetration.

    PubMed

    Gandolfi, Maria G; Sauro, Salvatore; Mannocci, Francesco; Watson, Timothy F; Zanna, Silvano; Capoferri, Michela; Prati, Carlo; Mongiorgi, Romano

    2007-06-01

    We aimed to compare the apical sealing ability of two experimental retrograde root-filling cements and mineral trioxide aggregate using a fluid filtration method. X-ray diffraction (XRD) and X-ray fluorescence spectrometry (XRF) were used to evaluate structural and qualitative characteristics. Thirty single-rooted extracted teeth were treated, root-end prepared, and obturated using MTA and two experimental cements. Fluid filtration was measured during a 5-minute period after 4, 24, and 48 hours and 1, 2, and 12 weeks. The results were statistically compared by using a two-way analysis of variance (p < 0.05). The marginal adaptation was evaluated by using a SEM replica technique. XRD analyses showed similar patterns. XRF showed lower amounts of SiO(2) and FeO(3) in the experimental cements. All cements showed a reduced fluid flow rate over time. No significant differences were found between the cements. The SEM replica indicated a good marginal adaptation to dentinal walls. Both experimental cements showed suitable properties as retrograde root-filling materials.

  2. The yeast Batten disease orthologue Btn1 controls endosome–Golgi retrograde transport via SNARE assembly

    PubMed Central

    Kama, Rachel; Kanneganti, Vydehi; Ungermann, Christian

    2011-01-01

    The human Batten disease gene CLN3 and yeast orthologue BTN1 encode proteins of unclear function. We show that the loss of BTN1 phenocopies that of BTN2, which encodes a retromer accessory protein involved in the retrieval of specific cargo from late endosomes (LEs) to the Golgi. However, Btn1 localizes to Golgi and regulates soluble N-ethyl-maleimide sensitive fusion protein attachment protein receptor (SNARE) function to control retrograde transport. Specifically, BTN1 overexpression and deletion have opposing effects on phosphorylation of the Sed5 target membrane SNARE, on Golgi SNARE assembly, and on Golgi integrity. Although Btn1 does not interact physically with SNAREs, it regulates Sed5 phosphorylation by modulating Yck3, a palmitoylated endosomal kinase. This may involve modification of the Yck3 lipid anchor, as substitution with a transmembrane domain suppresses the deletion of BTN1 and restores trafficking. Correspondingly, deletion of YCK3 mimics that of BTN1 or BTN2 with respect to LE–Golgi retrieval. Thus, Btn1 controls retrograde sorting by regulating SNARE phosphorylation and assembly, a process that may be adversely affected in Batten Disease patients. PMID:21987636

  3. Retrograde catheterization of the urinary bladder in healthy male goats by use of angiographic catheters.

    PubMed

    Reppert, Emily J; Streeter, Robert N; Simpson, Katharine M; Taylor, Jared D

    2016-11-01

    OBJECTIVE To identify and evaluate 3 types of angiographic catheters for retrograde urinary bladder catheterization in healthy male goats. ANIMALS 12 sexually intact yearling Alpine-cross bucks. PROCEDURES Three 5F angiographic catheters of the same length (100 cm) and diameter (0.17 cm) but differing in curvature at the tip were labeled A (straight tip), B (tip bent in 1 place), and C (tip bent in 2 places). During a single anesthetic episode, attempts were made to blindly pass each catheter into the urinary bladder of each goat. Order of catheters used was randomized, and the veterinarian passing the catheter was blinded as to catheter identity. The total number of attempts at catheter passage and the total number of successful attempts were recorded. RESULTS Catheter A was unsuccessfully passed in all 12 goats, catheter B was successfully passed in 8 goats, and catheter C was successfully passed in 4 goats. The success rate for catheter B was significantly greater than that for catheter A; however, no significant difference was identified between catheters B and C or catheters A and C. CONCLUSIONS AND CLINICAL RELEVANCE 2 angiographic catheters were identified that could be successfully, blindly advanced in a retrograde direction into the urinary bladder of healthy sexually intact male goats. Such catheters may be useful for determining urethral patency, emptying the urinary bladder, and instilling chemolysing agents in goats with clinical obstructive urolithiasis.

  4. Slit2 as a β-catenin/Ctnnb1-dependent retrograde signal for presynaptic differentiation

    PubMed Central

    Wu, Haitao; Barik, Arnab; Lu, Yisheng; Shen, Chengyong; Bowman, Andrew; Li, Lei; Sathyamurthy, Anupama; Lin, Thiri W; Xiong, Wen-Cheng; Mei, Lin

    2015-01-01

    Neuromuscular junction formation requires proper interaction between motoneurons and muscle cells. β-Catenin (Ctnnb1) in muscle is critical for motoneuron differentiation; however, little is known about the relevant retrograde signal. In this paper, we dissected which functions of muscle Ctnnb1 are critical by an in vivo transgenic approach. We show that Ctnnb1 mutant without the transactivation domain was unable to rescue presynaptic deficits of Ctnnb1 mutation, indicating the involvement of transcription regulation. On the other hand, the cell-adhesion function of Ctnnb1 is dispensable. We screened for proteins that may serve as a Ctnnb1-directed retrograde factor and identified Slit2. Transgenic expression of Slit2 specifically in the muscle was able to diminish presynaptic deficits by Ctnnb1 mutation in mice. Slit2 immobilized on beads was able to induce synaptophysin puncta in axons of spinal cord explants. Together, these observations suggest that Slit2 serves as a factor utilized by muscle Ctnnb1 to direct presynaptic differentiation. DOI: http://dx.doi.org/10.7554/eLife.07266.001 PMID:26159615

  5. Slit2 as a β-catenin/Ctnnb1-dependent retrograde signal for presynaptic differentiation.

    PubMed

    Wu, Haitao; Barik, Arnab; Lu, Yisheng; Shen, Chengyong; Bowman, Andrew; Li, Lei; Sathyamurthy, Anupama; Lin, Thiri W; Xiong, Wen-Cheng; Mei, Lin

    2015-07-10

    Neuromuscular junction formation requires proper interaction between motoneurons and muscle cells. β-Catenin (Ctnnb1) in muscle is critical for motoneuron differentiation; however, little is known about the relevant retrograde signal. In this paper, we dissected which functions of muscle Ctnnb1 are critical by an in vivo transgenic approach. We show that Ctnnb1 mutant without the transactivation domain was unable to rescue presynaptic deficits of Ctnnb1 mutation, indicating the involvement of transcription regulation. On the other hand, the cell-adhesion function of Ctnnb1 is dispensable. We screened for proteins that may serve as a Ctnnb1-directed retrograde factor and identified Slit2. Transgenic expression of Slit2 specifically in the muscle was able to diminish presynaptic deficits by Ctnnb1 mutation in mice. Slit2 immobilized on beads was able to induce synaptophysin puncta in axons of spinal cord explants. Together, these observations suggest that Slit2 serves as a factor utilized by muscle Ctnnb1 to direct presynaptic differentiation.

  6. Nucleotide specificities of anterograde and retrograde organelle transport in Reticulomyxa are indistinguishable.

    PubMed

    Schliwa, M; Shimizu, T; Vale, R D; Euteneuer, U

    1991-03-01

    Membrane-bound organelles move bidirectionally along microtubules in the freshwater ameba, Reticulomyxa. We have examined the nucleotide requirements for transport in a lysed cell model and compared them with kinesin and dynein-driven motility in other systems. Both anterograde and retrograde transport in Reticulomyxa show features characteristic of dynein but not of kinesin-powered movements: organelle transport is reactivated only by ATP and no other nucleoside triphosphates; the Km and Vmax of the ATP-driven movements are similar to values obtained for dynein rather than kinesin-driven movement; and of 15 ATP analogues tested for their ability to promote organelle transport, only 4 of them did. This narrow specificity resembles that of dynein-mediated in vitro transport and is dissimilar to the broad specificity of the kinesin motor (Shimizu, T., K. Furusawa, S. Ohashi, Y. Y. Toyoshima, M. Okuno, F. Malik, and R. D. Vale. 1991. J. Cell Biol. 112: 1189-1197). Remarkably, anterograde and retrograde organelle transport cannot be distinguished at all with respect to nucleotide specificity, kinetics of movement, and the ability to use the ATP analogues. Since the "kinetic fingerprints" of the motors driving transport in opposite directions are indistinguishable, the same type of motor(s) may be involved in the two directions of movement.

  7. The retrogradation of waxy maize starch extrudates: effects of storage temperature and water content.

    PubMed

    Farhat, I A; Blanshard, J M; Mitchell, J R

    2000-04-15

    The effects of water content and storage temperature on the kinetics of the retrogradation of nonexpanded waxy maize starch extrudates were studied using (1)H pulsed NMR and wide-angle X-ray diffraction. The increase in crystallinity observed by XRD was accompanied by a decrease in the relaxation times of the solid-like component of the NMR free induction and the spin-echo decays, and an increase in the contribution of the solid-like component to the total signal. The dependence of the rate of starch retrogradation on the storage temperature showed the typical "bell-shaped" behavior, which was successfully modeled using the Lauritzen-Hoffman theory of crystallization of chain-folded polymers. This theory was extended to model the effect of water content on the rate of isothermal crystallization by exploiting the ten-Brinke and Karasz, and the Flory equations to describe the dependence of the glass-transition and the melting temperatures on water content. Copyright 2000 John Wiley & Sons, Inc.

  8. Reversible disruption of dynactin 1-mediated retrograde axonal transport in polyglutamine-induced motor neuron degeneration.

    PubMed

    Katsuno, Masahisa; Adachi, Hiroaki; Minamiyama, Makoto; Waza, Masahiro; Tokui, Keisuke; Banno, Haruhiko; Suzuki, Keisuke; Onoda, Yu; Tanaka, Fumiaki; Doyu, Manabu; Sobue, Gen

    2006-11-22

    Spinal and bulbar muscular atrophy (SBMA) is a hereditary neurodegenerative disease caused by an expansion of a trinucleotide CAG repeat encoding the polyglutamine tract in the androgen receptor (AR) gene. To elucidate the pathogenesis of polyglutamine-mediated motor neuron dysfunction, we investigated histopathological and biological alterations in a transgenic mouse model of SBMA carrying human pathogenic AR. In affected mice, neurofilaments and synaptophysin accumulated at the distal motor axon. A similar intramuscular accumulation of neurofilament was detected in the skeletal muscle of SBMA patients. Fluoro-gold labeling and sciatic nerve ligation demonstrated an impaired retrograde axonal transport in the transgenic mice. The mRNA level of dynactin 1, an axon motor for retrograde transport, was significantly reduced in the SBMA mice resulting from pathogenic AR-induced transcriptional dysregulation. These pathological events were observed before the onset of neurological symptoms, but were reversed by castration, which prevents nuclear accumulation of pathogenic AR. Overexpression of dynactin 1 mitigated neuronal toxicity of the pathogenic AR in a cell culture model of SBMA. These observations indicate that polyglutamine-dependent transcriptional dysregulation of dynactin 1 plays a crucial role in the reversible neuronal dysfunction in the early stage of SBMA.

  9. Human Papillomavirus Type 16 Entry: Retrograde Cell Surface Transport along Actin-Rich Protrusions

    PubMed Central

    Schelhaas, Mario; Ewers, Helge; Rajamäki, Minna-Liisa; Day, Patricia M.; Schiller, John T.; Helenius, Ari

    2008-01-01

    The lateral mobility of individual, incoming human papillomavirus type 16 pseudoviruses (PsV) bound to live HeLa cells was studied by single particle tracking using fluorescence video microscopy. The trajectories were computationally analyzed in terms of diffusion rate and mode of motion as described by the moment scaling spectrum. Four distinct modes of mobility were seen: confined movement in small zones (30–60 nm in diameter), confined movement with a slow drift, fast random motion with transient confinement, and linear, directed movement for long distances. The directed movement was most prominent on actin-rich cell protrusions such as filopodia or retraction fibres, where the rate was similar to that measured for actin retrograde flow. It was, moreover, sensitive to perturbants of actin retrograde flow such as cytochalasin D, jasplakinolide, and blebbistatin. We found that transport along actin protrusions significantly enhanced HPV-16 infection in sparse tissue culture, cells suggesting a role for in vivo infection of basal keratinocytes during wound healing. PMID:18773072

  10. Dye screening and signal-to-noise ratio for retrogradely transported voltage-sensitive dyes.

    PubMed

    Tsau, Y; Wenner, P; O'Donovan, M J; Cohen, L B; Loew, L M; Wuskell, J P

    1996-12-28

    Using a novel method for retrogradely labeling specific neuronal populations, we tested different styryl dyes in attempt to find dyes whose staining would be specific, rapid, and lead to large activity dependent signals. The dyes were injected into the ventral roots of the isolated chick spinal cord from embryos at days E9-E12. The voltage-sensitive dye signals were recorded from synaptically activated motoneurons using a 464 element photodiode array. The best labeling and optical signals were obtained using the relatively hydrophobic dyes di-8-ANEPPQ and di-12-ANEPEQ. Over the 24 h period we examined, these dyes bound specifically to the cells with axons in the ventral roots. The dyes responded with an increase in fluorescence of 1-3% (delta F/F) in response to synaptic depolarization of the motoneurons. The signal-to-noise ratio obtained in a single trial from a detector that received light from a 14 x 14 microns2 area of the motoneuron population was about 10:1. Nonetheless, signals on neighboring diodes were similar, suggesting that we were not detecting the activity of individual neurons. Retrograde labeling and optical recording with voltage-sensitive dyes provides a means for monitoring the activity of identified neurons in situations where microelectrode recordings are not feasible.

  11. Local synthesis of dynein cofactors matches retrograde transport to acutely changing demands

    PubMed Central

    Villarin, Joseph M.; McCurdy, Ethan P.; Martínez, José C.; Hengst, Ulrich

    2016-01-01

    Cytoplasmic dynein mediates retrograde transport in axons, but it is unknown how its transport characteristics are regulated to meet acutely changing demands. We find that stimulus-induced retrograde transport of different cargos requires the local synthesis of different dynein cofactors. Nerve growth factor (NGF)-induced transport of large vesicles requires local synthesis of Lis1, while smaller signalling endosomes require both Lis1 and p150Glued. Lis1 synthesis is also triggered by NGF withdrawal and required for the transport of a death signal. Association of Lis1 transcripts with the microtubule plus-end tracking protein APC is required for their translation in response to NGF stimulation but not for their axonal recruitment and translation upon NGF withdrawal. These studies reveal a critical role for local synthesis of dynein cofactors for the transport of specific cargos and identify association with RNA-binding proteins as a mechanism to establish functionally distinct pools of a single transcript species in axons. PMID:28000671

  12. Glucocorticoids aggravate retrograde memory deficiency associated with traumatic brain injury in rats.

    PubMed

    Chen, Xin; Zhang, Ke-Li; Yang, Shu-Yuan; Dong, Jing-Fei; Zhang, Jian-Ning

    2009-02-11

    Administration of glucocorticoid to patients with head injury has previously been demonstrated to impair memory. We hypothesize that glucocorticoids promote post-traumatic hippocampal apoptosis, resulting in retrograde memory deficiency associated with traumatic brain injury (TBI). In the present study, we tested this hypothesis by measuring spatial memory deficiency in rats subjected to fluid percussion injury (FPI) and receiving dexamethasone (DXM at 0.5-10 mg/kg) or methylprednisolone (MP at 5-30 mg/kg); we also examined neuronal apoptosis in hippocampus. Adult male Wistar rats were trained for the acquisition of spatial memory, then subjected to FPI and tested for spatial reference memory on post-injury days 7 and 14 using the Morris Water Maze. Brain tissue from injured rats was examined 24 h to 2 weeks after injury. The percent time in the goal quadrant, which measures spatial reference memory, was significantly lower in injured rats receiving either high-dose DXM or MP than in control groups. TUNEL-positive cells in hippocampus were first detected 24 h post-injury, plateauing at 48h. The number of TUNEL-positive cells was significantly higher in injured rats treated with either DXM or MP. The data suggest that glucocorticoid therapy for TBI may increase neuronal apoptosis in hippocampus and, as a result, aggravate retrograde memory deficits induced by TBI.

  13. Treatment of hepatic hydatid disease complications using endoscopic retrograde cholangiopancreatography procedures

    PubMed Central

    Akaydin, Murat; Erozgen, Fazilet; Ersoy, Yeliz E.; Birol, Selim; Kaplan, Rafet

    2012-01-01

    Background Liver hydatidosis may lead to serious morbidity due to biliary complications, the management for which endoscopic sphincterotomy (ES) and biliary drainage are very efficient. We evaluated the effectiveness of endoscopic treatment for complications of hepatic hydatid disease. Methods We retrospectively reviewed endoscopic retrograde cholangiopancreatography (ERCP) procedures performed between January 2000 and December 2009 and compared laboratory findings, localization of the lesions and ERCP procedures applied between patients with and without jaundice. Results In all, 70 ERCP procedures were performed in 54 patients (24 men, 30 women). Of the 70 procedures, 24 were performed to treat jaundice. All patients with biliary fistulas and jaundice were managed with endoscopic procedures. The 70 ERCP procedures included sphincterotomy only (n = 40); sphincterotomy and stent placement (n = 7); stent placement only (n = 4); sphincterotomy and membrane extraction (n = 9); sphincterotomy, membrane extraction and pus drainage (n = 5); and sphincterotomy and pus drainage (n = 5). Laboratory results improved in 3–7 days, and bile leakage ceased in 2–21 days. Conclusion Endoscopic retrograde cholangiopancreatography is a safe and effective way to manage biliary complications of hepatic echinococcal disease. In most patients, ES is the most efficient treatment of postoperative external biliary fistulas, jaundice and accompanying cholangitis, as it enables clearing the bile ducts of hydatid remnants; ES should be performed since it accelerates the healing process by decreasing pressure in the choledochus. PMID:22617539

  14. Retrograde Instillation of Methylene Blue in the Difficult Diagnosis of BPF

    PubMed Central

    Ravenna, F.; Feo, C.; Calia, N.; Avoscan, C.; Barbetta, C.; Cavallesco, G. N.

    2012-01-01

    We report two cases in which we were able to diagnose bronchopleural fistula through retrograde methylene blue instillation during bronchoscopy. In the first case, methylene blue was injected through an abdominal drain, followed by air instillation and detected in the left bronchial tree, demonstrating the presence of a fistula in the lingula's bronchus. In the second case, methylene blue was injected into a pleural drain, through a breach on a surgical suture and detected in the right bronchial tree, demonstrating the presence of a fistula in the right inferior bronchus. The retrograde instillation of methylene blue, through a drain in the abdomen or the thoracic wall, is a safe, cheap, and practical method that allows the bronchoscopist to identify the presence of a fistula and, more importantly, to identify the exact point on the bronchial tree where a fistula is located. This provides the possibility of sealing the fistula with a variety of devices. It is our opinion that this procedure should be considered a primary method of diagnosis when a bronchopleural fistula is suspected and a drain on the thoracic or abdominal wall is positioned such that effusions are able to drain. PMID:23091498

  15. Comparison of rectal indomethacin, diclofenac, and naproxen for the prevention of post endoscopic retrograde cholangiopancreatography pancreatitis.

    PubMed

    Mohammad Alizadeh, Amir H; Abbasinazari, Mohammad; Hatami, Behzad; Abdi, Saeed; Ahmadpour, Forozan; Dabir, Shideh; Nematollahi, Aida; Fatehi, Samira; Pourhoseingholi, Mohammad A

    2017-03-01

    NSAIDs are commonly utilized for the prevention of post endoscopic retrograde cholangiopancreatography pancreatitis (PEP). However, not much is known about the most effective drug in preventing this complication. This study aims to clarify which drug (indomethacin, diclofenac, or naproxen) is most effective for the prevention of post endoscopic retrograde cholangiopancreatography (ERCP). In a double-blind, randomized study, patients received a single rectal dose of one of the three drugs 30 min before undergoing ERCP: diclofenac (100 mg), indomethacin (100 mg), or naproxen (500 mg). The primary outcome measured was the development of pancreatitis. The levels of serum amylase, lipase, lipoxin A4, and resolvin E1 were measured before ERCP, and at 24 h after the procedure. Three hundred and seventy-two patients completed the study. The overall incidence of PEP was 8.6%, which occurred in five of the 124 (4%) patients who received diclofenac, seven of the 122 (5.8%) patients who received indomethacin, and 20 of the 126 (15.9%) patients who received naproxen. There were no significant differences in amylase and lipase levels among the three groups (P=0.183 and 0.597, respectively). Unlike patients in the naproxen group, patients in the diclofenac and indomethacin groups showed a significant increase in lipoxin A4 and resolvin E1 (P=0.001 and 0.02, respectively). Diclofenac and indomethacin patient groups had a lower incidence of PEP than the naproxen group.

  16. Pregnancy by insemination of cryopreserved spermatozoa from a man with retrograde ejaculation: a case report.

    PubMed

    Okada, Hiroshi; Goda, Kazumasa; Koshida, Mitsunobu; Kamidono, Sadao

    2004-05-01

    Owing to the prevalence of diabetes mellitus, spinal injuries and aggressive surgical treatment of cancer, the number of younger patients with retrograde ejaculation is increasing. Since medical treatment to restore antegrade ejaculation often fails, several options for accomplishing insemination by these patients, including the use of sperm-rich urine obtained after masturbation and in vitro fertilization with sperm retrieved from the seminal tract, have been reported. We used the least invasive and most inexpensive procedure in a patient/couple with this condition. A 23-year-old man suffered from retrograde ejaculation after a spinal injury. He could achieve erection and engage in sexual intercourse but seldom had an orgasm or the sensation of ejaculation. We obtained spermatozoa from urine produced after masturbation at home and froze them. We used these frozen-thawed spermatozoa for intrauterine insemination, leading to the term birth of a healthy infant. In selected patient/couples, frozen spermatozoa obtained from postmasturbation urine can be used successfully for intrauterine insemination. This minimally invasive and most inexpensive procedure should be tried before planning in vitro fertilization.

  17. The retrograde IFT machinery of C. elegans cilia: two IFT dynein complexes?

    PubMed

    Hao, Limin; Efimenko, Evgeni; Swoboda, Peter; Scholey, Jonathan M

    2011-01-01

    We analyzed the relatively poorly understood IFT-dynein (class DYNC2)-driven retrograde IFT pathway in C. elegans cilia, which yielded results that are surprising in the context of current models of IFT. Assays of C. elegans dynein gene expression and intraflagellar transport (IFT) suggest that conventional IFT-dynein contains essential heavy (CHE-3), light-intermediate (XBX-1), plus three light polypeptide chains that participate in IFT, but no "essential" intermediate chain. IFT assays of XBX-1::YFP suggest that IFT-dynein is transported as cargo to the distal tip of the cilium by kinesin-2 motors, but independent of the IFT-particle/BBSome complexes. Finally, we were surprised to find that the subset of cilia present on the OLQ (outer labial quadrant) neurons assemble independently of conventional "CHE-3" IFT-dynein, implying that there is a second IFT-dynein acting in these cilia. We have found a novel gene encoding a dynein heavy chain, DHC-3, and two light chains, in OLQ neurons, which could constitute an IFT-dynein complex in OLQ neuronal cilia. Our results underscore several surprising features of retrograde IFT that require clarification.

  18. Tectonic history of subduction zones inferred from retrograde blueschist P-T paths

    SciTech Connect

    Ernst, W.G. )

    1988-12-01

    Many Phanerozoic convergent plate junctions are marked by discontinuous blueschist belts, reflecting relatively high-pressure (P) prograde trajectories. Common blueschist paragneisses, such as those of the western Alps, exhibit widespread overprinting by greenschist and/or epidote-amphibolite facies assemblages. For this type of high-P belt, retrograde metamorphism involved fairly rapid, nearly isothermal decompression; some terranes underwent continued heating during early stages of pressure release. Uplift probably occurred as a consequence of the entrance of an island arc, oceanic plateau, or segment of continental crust into the subduction zone (collision), resulting in marked deceleration or cessation of underflow and buoyant, approximately adiabatic rise of the stranded, recrystallized subduction complex. Other high-P belts, such as the Franciscan of western California, preserve metamorphic aragonite and lack a low-P overprint; retrogression approximately retraced the prograde P-T (temperature) path, or for early formed high-grade blocks, occurred at even higher P/T ratios. Parts of this type of metamorphic belt evidently migrated slowly back up the subduction zone in response to isostatic forces during continued plate descent and refrigeration. Upward motion took place as tectonically imbricated slices, as laminar return flow in melange zones, and perhaps partly a lateral spreading/extension of the underplated accretionary prism. Retrograde P-T trajectories of high-P belts therefore provide important constraints on the tectonic evolution of convergent plate junctions.

  19. DSC studies of retrogradation and amylose lipid complex transition taking place in gamma irradiated wheat starch

    NASA Astrophysics Data System (ADS)

    Cieśla, K.; Eliasson, A. C.

    2007-12-01

    The effect of gamma irradiation ( 60Co) with doses of 5-30 kGy on the amylose-lipid complex transition and retrogradation occurring in gels containing ca. 50% and ca. 20% wheat starch was studied by differential scanning calorimetry (DSC) during heating-cooling-heating cycles (up to three cycles). Transition of the amylose-lipid complex occurs in all the irradiated samples at a lower temperature as compared to the non-irradiated starch. That effect was larger when the radiation dose was higher. A further thermal treatment causes a decrease of the transition temperature in the irradiated samples, with no effect or increase of that temperature observed for the non-irradiated ones. Irradiation hinders retrogradation taking place in 50% gels but facilitates the process occurring in 20% gels. The differences between the irradiated and the non-irradiated samples are more evident in the every next heating or cooling cycle as well as after storage and in the case of ca. 50% suspensions as compared to ca. 20% suspensions. The results point out to the deterioration of the structure of the complexes formed in the irradiated starch as compared to the non-irradiated one.

  20. Alterations of mitochondrial dynamics allow retrograde propagation of locally initiated axonal insults

    PubMed Central

    Lassus, Benjamin; Magifico, Sebastien; Pignon, Sandra; Belenguer, Pascale; Miquel, Marie-Christine; Peyrin, Jean-Michel

    2016-01-01

    In chronic neurodegenerative syndromes, neurons progressively die through a generalized retraction pattern triggering retrograde axonal degeneration toward the cell bodies, which molecular mechanisms remain elusive. Recent observations suggest that direct activation of pro-apoptotic signaling in axons triggers local degenerative events associated with early alteration of axonal mitochondrial dynamics. This raises the question of the role of mitochondrial dynamics on both axonal vulnerability stress and their implication in the spreading of damages toward unchallenged parts of the neuron. Here, using microfluidic chambers, we assessed the consequences of interfering with OPA1 and DRP1 proteins on axonal degeneration induced by local application of rotenone. We found that pharmacological inhibition of mitochondrial fission prevented axonal damage induced by rotenone, in low glucose conditions. While alteration of mitochondrial dynamics per se did not lead to spontaneous axonal degeneration, it dramatically enhanced axonal vulnerability to rotenone, which had no effect in normal glucose conditions, and promoted retrograde spreading of axonal degeneration toward the cell body. Altogether, our results suggest a mitochondrial priming effect in axons as a key process of axonal degeneration. In the context of neurodegenerative diseases, like Parkinson’s and Alzheimer’s, mitochondria fragmentation could hasten neuronal death and initiate spatial dispersion of locally induced degenerative events. PMID:27604820

  1. Relative importance of moisture migration and amylopectin retrogradation for pound cake crumb firming.

    PubMed

    Luyts, A; Wilderjans, E; Van Haesendonck, I; Brijs, K; Courtin, C M; Delcour, J A

    2013-12-15

    Moisture migration largely impacts cake crumb firmness during storage at ambient temperature. To study the importance of phenomena other than crumb to crust moisture migration and to exclude moisture and temperature gradients during baking, crustless cakes were baked using an electrical resistance oven (ERO). Cake crumb firming was evaluated by texture analysis. First, ERO cakes with properties similar to those baked conventionally were produced. Cake batter moisture content (MC) was adjusted to ensure complete starch gelatinisation in the baking process. In cakes baked conventionally, most of the increase in crumb firmness during storage was caused by moisture migration. Proton nuclear magnetic resonance ((1)H NMR) showed that the population containing protons of crystalline starch grew during cake storage. These and differential scanning calorimetry (DSC) data pointed to only limited amylopectin retrogradation. The limited increase in amylopectin retrogradation during cake storage cannot solely account for the significant firming of ERO cakes and, hence, other phenomena are involved in cake firming. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Nucleotide specificities of anterograde and retrograde organelle transport in Reticulomyxa are indistinguishable

    PubMed Central

    1991-01-01

    Membrane-bound organelles move bidirectionally along microtubules in the freshwater ameba, Reticulomyxa. We have examined the nucleotide requirements for transport in a lysed cell model and compared them with kinesin and dynein-driven motility in other systems. Both anterograde and retrograde transport in Reticulomyxa show features characteristic of dynein but not of kinesin-powered movements: organelle transport is reactivated only by ATP and no other nucleoside triphosphates; the Km and Vmax of the ATP-driven movements are similar to values obtained for dynein rather than kinesin-driven movement; and of 15 ATP analogues tested for their ability to promote organelle transport, only 4 of them did. This narrow specificity resembles that of dynein-mediated in vitro transport and is dissimilar to the broad specificity of the kinesin motor (Shimizu, T., K. Furusawa, S. Ohashi, Y. Y. Toyoshima, M. Okuno, F. Malik, and R. D. Vale. 1991. J. Cell Biol. 112: 1189-1197). Remarkably, anterograde and retrograde organelle transport cannot be distinguished at all with respect to nucleotide specificity, kinetics of movement, and the ability to use the ATP analogues. Since the "kinetic fingerprints" of the motors driving transport in opposite directions are indistinguishable, the same type of motor(s) may be involved in the two directions of movement. PMID:1825662

  3. Arthroscopic retrograde osteochondral autologous transplantation to chondral lesion in femoral head.

    PubMed

    Cetinkaya, Sarper; Toker, Berkin; Taser, Omer

    2014-06-01

    This report describes the treatment of 2 cases of full-thickness cartilage defect of the femoral head. The authors performed osteochondral autologous transplantation with a different technique that has not been reported to date. One patient was 37 years old, and the other was 42 years old. Both presented with hip pain. In both patients, radiograph and magnetic resonance imaging scan showed a focal chondral defect on the weight-bearing area of the femoral head and acetabular impingement. A retrograde osteochondral autologous transplantation technique combined with hip arthroscopy and arthroscopic impingement treatment was performed. After a 2-month recovery period, the symptoms were resolved. In the first year of follow-up, Harris Hip scores improved significantly (case 1, 56.6 to 87.6; case 2, 58.6 to 90). The technique described yielded good short- and midterm clinical and radiologic outcomes. To the authors' knowledge, this report is the first to describe a retrograde osteochondral transplantation technique performed with hip arthroscopy in the femoral head.

  4. Identification of the origin of catecholaminergic inputs to HVc in canaries by retrograde tract tracing combined with tyrosine hydroxylase immunocytochemistry.

    PubMed

    Appeltants, D; Absil, P; Balthazart, J; Ball, G F

    2000-03-01

    The telencephalic nucleus HVc (sometimes referred to as the high vocal center) plays a key role in the production and perception of birdsong. Although many afferent and efferent connections to this nucleus have been described, it has been clear for many years, based on chemical neuroanatomical criteria, that there are projections to this nucleus that remain undescribed. A variety of methods including high performance liquid chromatography, immunohistochemistry and receptor autoradiography have identified high levels of catecholamine transmitters, the presence of enzymes involved in the synthesis of catecholamines such as tyrosine hydroxylase and a variety of catecholamine receptor sub-types in the HVc of several songbird species. However, no definitive projections to HVc have been described from cells groups known to synthesize catecholamines. These projections were analyzed in the present study by retrograde tract tracing combined with immunocytochemistry for tyrosine hydroxylase. The origin of the catecholaminergic inputs to HVc were determined based exclusively on birds in which injections of the retrograde tracer (latex fluospheres) were confined within the cytoarchitectonic boundaries of the nucleus. Retrogradely transported latex fluospheres were found mainly in cells of two dopaminergic nuclei, the mesencephalic central gray (A11) and, to a lesser extend, the area ventralis of Tsai (A10; homologous to the ventral tegmental area of mammals). A few retrogradely-labelled cells were also found in the noradrenergic nucleus subceruleus (A6). Most of these retrogradely-labelled cells were also tyrosine hydroxylase-positive. Other catecholaminergic nuclei were devoid of retrograde label. These data converge with others studies to indicate that HVc receives discrete dopaminergic and noradrenergic inputs. These inputs may influence the steroid regulation of HVc, attentional processes related to song and modulate sensory inputs to the song system.

  5. Body surface mapping of retrograde P waves in the intact dog by simulation of accessory pathway re-entry.

    PubMed

    Pintér, A; Molin, F; Savard, P; Tremblay, G; Sierra, G; Nadeau, R

    2000-02-01

    To investigate a noninvasive technique to localize the atrial insertion site of concealed accessory pathways based on the analysis of body surface potential maps (BSPMs) of retrograde P waves in dogs with simulated retrograde pathways. Orthodromic tachycardias were simulated by atrial stimulations at eight different sites around the atrioventricular ring with long (250 ms and 300 ms) and short (100 ms and 130 ms) coupling times in 14 anesthetized dogs to have P waves well separated from the T wave or occurring during the T wave, respectively. The distance between pacing sites was 15 to 40 mm in group 1 (eight dogs) and 2 mm (in the right atrial free wall region) in group 2 (six dogs). Beats were signal-averaged during 30 s and BSPMs were constructed from 63 unipolar leads. The P wave BSPM pattern for any specific stimulation site was stable and reproducible (correlation coefficient greater than 0.98), and similar in different dogs at long coupling interval stimulations. The thoracic distribution of negative potentials and position of the potential minimum clearly identified the stimulation site when long coupling time stimulations were used. The spatial resolution of the technique as determined by comparison of correlation coefficients in group 2 was 6 mm (P<0.05). When short coupling time stimulations were used (fast tachycardia simulation), the T wave masked the P wave potential distribution in four of eight dogs, but the retrograde P wave map could still be accurately extracted by subtracting a straight line joining the onset and offset of the P wave in 24 of 28 (86%) of the tachycardia simulation sites in these four dogs. The BSPM patterns of simulated retrograde P waves are specifically related to the site of atrial stimulation. Although the T wave altered these BSPM patterns, a subtraction technique recovered the pattern of the retrograde P wave in 93% of all simulated orthodromic tachycardias. The spatial resolution of the retrograde P wave BSPM method was 6

  6. Retrograde nuclear transport from the cytoplasm is required for tRNA(Tyr) maturation in T. brucei.

    PubMed

    Kessler, Alan C; Kulkarni, Sneha S; Paulines, Mellie J; Rubio, Mary Anne T; Limbach, Patrick A; Paris, Zdeněk; Alfonzo, Juan D

    2017-09-13

    Retrograde transport of tRNAs from the cytoplasm to the nucleus was first described in Saccharomyces cerevisiae and most recently in mammalian systems. Although the function of retrograde transport is not completely clear, it plays a role in the cellular response to changes in nutrient availability. Under low nutrient conditions tRNAs are sent from the cytoplasm to nucleus and presumably remain in storage there until nutrient levels improve. However, in S. cerevisiae tRNA retrograde transport is constitutive and occurs even when nutrient levels are adequate. Constitutive transport is important, at least, for the proper maturation of tRNA(Phe), which undergoes cytoplasmic splicing, but requires the action of a nuclear modification enzyme that only acts on a spliced tRNA. A lingering question in retrograde tRNA transport is whether it is relegated to S. cerevisiae and multicellular eukaryotes or alternatively, is a pathway with deeper evolutionary roots. In the early branching eukaryote T. brucei, tRNA splicing, like in yeast, occurs in the cytoplasm. In the present report, we have used a combination of cell fractionation and molecular approaches that show the presence of significant amounts of spliced tRNA(Tyr) in the nucleus of T. brucei. Notably, the modification enzyme tRNA-guanine transglycosylase (TGT) localizes to the nucleus and, as shown here, is not able to add queuosine (Q) to an intron-containing tRNA. We suggest that retrograde transport is partly the result of the differential intracellular localization of the splicing machinery (cytoplasmic) and a modification enzyme, TGT (nuclear). These findings expand the evolutionary distribution of retrograde transport mechanisms to include early diverging eukaryotes, while highlighting its importance for queuosine biosynthesis.

  7. Retrograde Stent-assisted Coil Embolization of Wide-neck or Branch-incorporated Posterior Communicating Artery Aneurysm

    PubMed Central

    Park, Jeong Woo; Choi, Kyu Sun; Park, Dong Woo; Ryu, Je Il; Kim, Jae Min; Kim, Choong Hyun

    2016-01-01

    Endovascular coil embolization using a balloon- or stent-assisted technique for the treatment of wide-necked posterior communicating artery (PcomA) aneurysms is well established. However, complete aneurysm occlusion with preservation of the PcomA can be difficult in case of wide-neck aneurysms with a PcomA incorporation. We present two cases of stent-assisted coil embolization using a retrograde approach through the posterior circulation for wide-neck or branch-incorporated PcomA aneurysms. Retrograde stenting was successful without periprocedural complications. These aneurysms were completely occluded. The patency of the PcomA was maintained in all cases. PMID:27790404

  8. Intra-arterial urokinase for treatment of retrograde thrombosis following resection of an arteriovenous malformation. Case report.

    PubMed

    Sipos, E P; Kirsch, J R; Nauta, H J; Debrun, G; Ulatowski, J A; Bell, W R

    1992-06-01

    Retrograde thrombosis of feeding arteries is a potentially catastrophic complication occasionally reported following resection of arteriovenous malformations (AVM's). No successful therapy for this condition, which causes postoperative stroke, has previously been reported. A case of retrograde thrombosis of the left middle cerebral artery immediately following resection of a parietal AVM is reported in a patient with a retained intra-arterial catheter from preoperative embolization. The administration of urokinase within 4 hours of surgery resulted in dramatic clinical and angiographic improvement without hemorrhagic complications. While urokinase is considered highly experimental in this setting, this case demonstrates that thrombolytic agents should be viewed as therapeutic options worthy of further investigation.

  9. Vascular Plug-Assisted Retrograde Transvenous Obliteration of Portosystemic Shunts for Refractory Hepatic Encephalopathy: A Case Report

    PubMed Central

    Park, Jonathan K.; Cho, Sung-Ki; Kee, Stephen; Lee, Edward W.

    2014-01-01

    While balloon-assisted retrograde transvenous obliteration (BRTO) has been used for two decades in Asia for the management of gastric variceal bleeding, it is still an emerging therapy elsewhere. Given the shunt closure brought about by the procedure, BRTO has also been used for the management of portosystemic encephalopathy with promising results. Modified versions of BRTO have been developed, including plug-assisted retrograde transvenous obliteration (PARTO), where a vascular plug is deployed within a portosystemic shunt. To our knowledge, we present the first North American case of PARTO in the setting of a large splenorenal shunt for the management of portosystemic encephalopathy. PMID:24744943

  10. Vascular plug-assisted retrograde transvenous obliteration of portosystemic shunts for refractory hepatic encephalopathy: a case report.

    PubMed

    Park, Jonathan K; Cho, Sung-Ki; Kee, Stephen; Lee, Edward W

    2014-01-01

    While balloon-assisted retrograde transvenous obliteration (BRTO) has been used for two decades in Asia for the management of gastric variceal bleeding, it is still an emerging therapy elsewhere. Given the shunt closure brought about by the procedure, BRTO has also been used for the management of portosystemic encephalopathy with promising results. Modified versions of BRTO have been developed, including plug-assisted retrograde transvenous obliteration (PARTO), where a vascular plug is deployed within a portosystemic shunt. To our knowledge, we present the first North American case of PARTO in the setting of a large splenorenal shunt for the management of portosystemic encephalopathy.

  11. Gαq/11-mediated intracellular calcium responses to retrograde flow in endothelial cells.

    PubMed

    Melchior, Benoît; Frangos, John A

    2012-08-15

    Disturbed flow patterns, including reversal in flow direction, are key factors in the development of dysfunctional endothelial cells (ECs) and atherosclerotic lesions. An almost immediate response of ECs to fluid shear stress is the increase in cytosolic calcium concentration ([Ca(2+)](i)). Whether the source of [Ca(2+)](i) is extracellular, released from Ca(2+) intracellular stores, or both is still undefined, though it is likely dependent on the nature of forces involved. We have previously shown that a change in flow direction (retrograde flow) on a flow-adapted endothelial monolayer induces the remodeling of the cell-cell junction along with a dramatic [Ca(2+)](i) burst compared with cells exposed to unidirectional or orthograde flow. The heterotrimeric G protein-α q and 11 subunit (Gα(q/11)) is a likely candidate in effecting shear-induced increases in [Ca(2+)](i) since its expression is enriched at the junction and has been previously shown to be activated within seconds after onset of flow. In flow-adapted human ECs, we have investigated to what extent the Gα(q/11) pathway mediates calcium dynamics after reversal in flow direction. We observed that the elapsed time to peak [Ca(2+)](i) response to a 10 dyn/cm(2) retrograde shear stress was increased by 11 s in cells silenced with small interfering RNA directed against Gα(q/11). A similar lag in [Ca(2+)](i) transient was observed after cells were treated with the phospholipase C (PLC)-βγ inhibitor, U-73122, or the phosphatidylinositol-specific PLC inhibitor, edelfosine, compared with controls. Lower levels of inositol 1,4,5-trisphosphate accumulation seconds after the onset of flow correlated with the increased lag in [Ca(2+)](i) responses observed with the different treatments. In addition, inhibition of the inositol 1,4,5-trisphosphate receptor entirely abrogated flow-induced [Ca(2+)](i). Taken together, our results identify the Gα(q/11)-PLC pathway as the initial trigger for retrograde flow

  12. M1 ipRGCs Influence Visual Function through Retrograde Signaling in the Retina.

    PubMed

    Prigge, Cameron L; Yeh, Po-Ting; Liou, Nan-Fu; Lee, Chi-Chan; You, Shih-Feng; Liu, Lei-Lei; McNeill, David S; Chew, Kylie S; Hattar, Samer; Chen, Shih-Kuo; Zhang, Dao-Qi

    2016-07-06

    Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs, with five subtypes named M1-M5) are a unique subclass of RGCs with axons that project directly to many brain nuclei involved in non-image-forming functions such as circadian photoentrainment and the pupillary light reflex. Recent evidence suggests that melanopsin-based signals also influence image-forming visual function, including light adaptation, but the mechanisms involved are unclear. Intriguingly, a small population of M1 ipRGCs have intraretinal axon collaterals that project toward the outer retina. Using genetic mouse models, we provide three lines of evidence showing that these axon collaterals make connections with upstream dopaminergic amacrine cells (DACs): (1) ipRGC signaling to DACs is blocked by tetrodotoxin both in vitro and in vivo, indicating that ipRGC-to-DAC transmission requires voltage-gated Na(+) channels; (2) this transmission is partly dependent on N-type Ca(2+) channels, which are possibly expressed in the axon collateral terminals of ipRGCs; and (3) fluorescence microscopy reveals that ipRGC axon collaterals make putative presynaptic contact with DACs. We further demonstrate that elimination of M1 ipRGCs attenuates light adaptation, as evidenced by an impaired electroretinogram b-wave from cones, whereas a dopamine receptor agonist can potentiate the cone-driven b-wave of retinas lacking M1 ipRGCs. Together, the results strongly suggest that ipRGCs transmit luminance signals retrogradely to the outer retina through the dopaminergic system and in turn influence retinal light adaptation. Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) comprise a third class of retinal photoreceptors that are known to mediate physiological responses such as circadian photoentrainment. However, investigation into whether and how ipRGCs contribute to vision has just begun. Here, we provide convergent anatomical and physiological evidence that

  13. Proficiency of virtual reality simulator training in flexible retrograde ureteroscopy renal stone management.

    PubMed

    Cai, Jian-liang; Zhang, Yi; Sun, Guo-feng; Li, Ning-chen; Yuan, Xue-li; Na, Yan-qun

    2013-10-01

    Minimally invasive flexible ureteroscopy techniques have widely adopted in the management of patients with renal stones. We performed this study to investigate the value of virtual reality simulator training in retrograde flexible ureteroscopy renal stone treatment for catechumen. Thirty catechumen, included 17 attending physicians and 13 associate chief physicians, were selected for study. The trainees first underwent 1-hour basic training to get familiar with the instrument and basic procedures, then followed by 4-hour practice on virtual reality simulators. Before and after the 4-hour training, all trainees undertake an assessment with task 7 program (right low pole calyces stone management). We documented for each trainee the total time of procedure, time of progressing from the orifice to stone, stone translocation and fragmentation time, laser operate proficiency scale, total laser energy, maximal size of residual stone fragments, number of trauma from the scopes and tools, damage to the scope and global rating scale (GRS). The proficiency of this training program was analyzed by the comparison of the first and second assessment outcomes. Significant improvement was observed in retrograde flexible ureteroscopy management of renal stone on virtual reality simulators after finishing the 4 hour special-purpose training. This was demonstrated by improvement in total procedure time ((18.37±2.59) minutes vs. (38.67±1.94) minutes), progressing time from the orifice to stone ((4.00±1.08) minutes vs. (13.80±2.01) minutes), time of stone translocation ((1.80±0.71) minutes vs. (6.57±1.01) minutes), fragmentation time ((4.43±1.25) minutes vs. (13.53±1.46) minutes), laser operate proficiency scale (8.47±0.73 vs. 3.77±0.77), total laser energy ((3231.6±401.4) W vs. (5329.8±448.9) W), maximal size of residual stone fragments ((2.66±0.39) mm vs. (5.77±0.63) mm), number of trauma from the scopes and tools (3.27±1.01 vs. 10.37±3.02), damage to the scope (0 vs

  14. The evolution of a binary in a retrograde circular orbit embedded in an accretion disk

    NASA Astrophysics Data System (ADS)

    Ivanov, P. B.; Papaloizou, J. C. B.; Paardekooper, S.-J.; Polnarev, A. G.

    2015-04-01

    Aims: Supermassive black hole binaries may form as a consequence of galaxy mergers. Both prograde and retrograde orbits have been proposed. We study a binary with a small mass ratio, q, in a retrograde orbit immersed in and interacting with a gaseous accretion disk in order to estimate the time scales for inward migration that leads to coalescence and the accretion rate to the secondary component. Methods: We employed both semi-analytic methods and two-dimensional numerical simulations, focusing on the case where the binary mass ratio is small but large enough to significantly perturb the disk. Results: We develop the theory of type I migration in this case and go on to determine the conditions for gap formation. We find that when this happens inward migration occurs on a time scale equal to the time required for one half of the secondary mass to be accreted through the unperturbed accretion disk. The accretion rate onto the secondary itself is found to only play a minor role in the orbital evolution as it is of the order of q1/3 of that to the primary. We obtain good general agreement between the semi-analytic and fully numerical approaches and note that the former can be applied to disks with a wide dynamic range on long time scales. Conclusions: We conclude that inward migration induced by interaction with the disk can enable the binary to migrate inwards, alleviating the so-called final parsec problem. When q is sufficiently small, there is no well-pronounced cavity inside the binary orbit, unlike the prograde case. The accretion rate to the secondary does not influence the binary orbital evolution much, but can lead to some interesting observational consequences, provided the accretion efficiency is sufficiently large. In this case the binary may be detected as, for example, two sources of radiation rotating around each other. However, the study should be extended to consider orbits with significant eccentricity and the effects of gravitational radiation at

  15. Optical imaging of neuronal activity in tissue labeled by retrograde transport of Calcium Green Dextran.

    PubMed

    McPherson, D R; McClellan, A D; O'Donovan, M J

    1997-05-01

    In many neurophysiological studies it is desirable to simultaneously record the activity of a large number of neurons. This is particularly true in the study of vertebrate motor systems that generate rhythmic behaviors, such as the pattern generator for locomotion in vertebrate spinal cord. Optical imaging of neurons labeled with appropriate fluorescent dyes, in which fluorescence is activity-dependent, provides a means to record the activity of many neurons at the same time, while also providing fine spatial resolution of the position and morphology of active neurons. Voltage-sensitive dyes have been explored for this purpose and have the advantage of rapid response to transmembrane voltage changes. However, voltage-sensitive dyes bleach readily, which results in phototoxic damage and limits the time that labeled neurons can be imaged. In addition, the signal-to-noise ratio is typically small, so that averaging of responses is usually required. As an alternative to voltage-sensitive dyes, calcium-sensitive dyes can exhibit large changes in fluorescence. Most neurons contain voltage-sensitive Ca2+ channels, and numerous reports indicate that neuronal activity is accompanied by increased intracellular Ca2+ concentration. In this protocol we describe a method to use retrograde transport of the dextran conjugate of a calcium-sensitive dye (Calcium Green Dextran) to label selectively populations of brain and spinal interneurons in a primitive vertebrate (lamprey), for subsequent video-rate imaging of changes in intracellular fluorescence during neuronal activity. Although described with specific reference to lampreys, the technique has also been applied to embryonic chick spinal cord and larval zebrafish preparations and should be easily adaptable to other systems. The most significant novel feature of the protocol is the use of retrograde axonal transport to selectively fill neurons that have known axonal trajectories. Using lampreys, we have obtained activity

  16. Botulinum Neurotoxins A and E Undergo Retrograde Axonal Transport in Primary Motor Neurons

    PubMed Central

    Manich, Maria; Bercsenyi, Kinga; Menendez, Guillermo; Rossetto, Ornella; Caleo, Matteo; Schiavo, Giampietro

    2012-01-01

    The striking differences between the clinical symptoms of tetanus and botulism have been ascribed to the different fate of the parental neurotoxins once internalised in motor neurons. Tetanus toxin (TeNT) is known to undergo transcytosis into inhibitory interneurons and block the release of inhibitory neurotransmitters in the spinal cord, causing a spastic paralysis. In contrast, botulinum neurotoxins (BoNTs) block acetylcholine release at the neuromuscular junction, therefore inducing a flaccid paralysis. Whilst overt experimental evidence supports the sorting of TeNT to the axonal retrograde transport pathway, recent findings challenge the established view that BoNT trafficking is restricted to the neuromuscular junction by highlighting central effects caused by these neurotoxins. These results suggest a more complex scenario whereby BoNTs also engage long-range trafficking mechanisms. However, the intracellular pathways underlying this process remain unclear. We sought to fill this gap by using primary motor neurons either in mass culture or differentiated in microfluidic devices to directly monitor the endocytosis and axonal transport of full length BoNT/A and BoNT/E and their recombinant binding fragments. We show that BoNT/A and BoNT/E are internalised by spinal cord motor neurons and undergo fast axonal retrograde transport. BoNT/A and BoNT/E are internalised in non-acidic axonal carriers that partially overlap with those containing TeNT, following a process that is largely independent of stimulated synaptic vesicle endo-exocytosis. Following intramuscular injection in vivo, BoNT/A and TeNT displayed central effects with a similar time course. Central actions paralleled the peripheral spastic paralysis for TeNT, but lagged behind the onset of flaccid paralysis for BoNT/A. These results suggest that the fast axonal retrograde transport compartment is composed of multifunctional trafficking organelles orchestrating the simultaneous transfer of diverse cargoes

  17. Antioxidant drugs to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis: What does evidence suggest?

    PubMed Central

    Fuentes-Orozco, Clotilde; Dávalos-Cobián, Carlos; García-Correa, Jesús; Ambriz-González, Gabriela; Macías-Amezcua, Michel Dassaejv; García-Rentería, Jesús; Rendón-Félix, Jorge; Chávez-Tostado, Mariana; Cuesta-Márquez, Lizbeth Araceli; Alvarez-Villaseñor, Andrea Socorro; Cortés-Flores, Ana Olivia; González-Ojeda, Alejandro

    2015-01-01

    AIM: To determine whether or not the use of antioxidant supplementation aids in the prevention of post- endoscopic retrograde cholangiopancreatography pancreatitis. METHODS: A systematic review of randomized controlled trials (RCTs) was made to evaluate the preventive effect of prophylactic antioxidant supplementation in post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). The inclusion criteria included: acute post-endoscopic retrograde cholangiopancreatography pancreatitis in adults; randomized clinical trials with the use of any antioxidant as an intervention compared with placebo, to reduce PEP. The outcome measure was the incidence and severity of PEP. Twelve RCTs involving 3110 patients since 1999 were included. The antioxidants used were selenite, β-carotene, and pentoxifylline (each one in one trial), N-acetylcysteine (NAC) in three trials, and allopurinol in six trials. The group of patients treated with NAC received different doses; either oral or intravenous, and allopurinol-treated patients received five different oral doses in two different administration periods. The results are expressed with raw numbers, proportions, as well as mean and standard deviations. The incidence of pancreatitis between groups was analyzed with Pearson’s χ2 test or Fisher’s exact test (F). The main outcome is expressed as relative risks and 95%CI. RESULTS: The incidence of pancreatitis in all antioxidant treatment groups was 8.6%, whereas it was 9.7% in the control group. The antioxidants used were selenite, β-carotene, and pentoxifylline (each one in one trial), NAC in three trials, and allopurinol in six trials. In allopurinol trials, three different dosifications were used; two trials reported a low dosage (of less than 400 mg), two trials reported a moderate dose (600 mg) and the remaining two employed higher doses (more than 900 mg). Supplementation was not associated with a significant reduction in the incidence of PEP [relative risk (RR) = 0

  18. Diffusion along interphase boundaries and its effect on retrograde zoning patterns of metamorphic minerals

    NASA Astrophysics Data System (ADS)

    Keller, L. M.; Hauzenberger, C. A.; Abart, R.

    2007-08-01

    In this study we use two dimensional chemical patterns and numerical modeling to estimate the relative rates of chemical transport along interphase boundaries (ib) and through grain (s) interiors during retrograde Fe-Mg exchange between garnet and biotite at a garnet-biotite-quartz triple junction. We demonstrate that systematic variations in garnet-rim compositions, which are frequently observed along garnet-quartz interfaces, and deviations from concentric retrograde zoning patterns start to develop when chemical transport along the interphase boundaries becomes slow during cooling. The capacities for chemical transport along an interphase boundary depend on the product D ib K ib/s a, where D ib is the diffusion coefficient of the exchangeable components within the interphase boundary medium, K ib/s is the equilibrium partitioning coefficient between the cation exchange partners and the interphase boundary medium and a is the interphase boundary width. The model is applied to analyze the retrograde zoning patterns in garnets from the Mozambique belt (SE-Kenya), which cooled from 820°C at a rate of ca. 2°C/my. It is found that non-equilibrated compositions in garnet along garnet/quartz interphase boundaries started to develop below 700°C due to insufficient rates of chemical transport along these boundaries. The transport capacities of garnet/quartz interphase boundaries was estimated to have been between about 1E-23 cm3/s (575°C) and 1E-20 cm3/s (700°C) from modeling the observed X Fe pattern in garnet close to a garnet-quartz-biotite triple junction and relying on published data on the diffusivity of Fe2+ in garnet. Similar transport capacities are obtained; when the interphase boundary is assumed to be filled with a material that has the transport properties and chemical composition of a free melt in equilibrium with garnet, biotite and quartz at the respective conditions. In contrast, if the transport properties of the interphase boundary medium are

  19. Antioxidant drugs to prevent post-endoscopic retrograde cholangiopancreatography pancreatitis: What does evidence suggest?

    PubMed

    Fuentes-Orozco, Clotilde; Dávalos-Cobián, Carlos; García-Correa, Jesús; Ambriz-González, Gabriela; Macías-Amezcua, Michel Dassaejv; García-Rentería, Jesús; Rendón-Félix, Jorge; Chávez-Tostado, Mariana; Cuesta-Márquez, Lizbeth Araceli; Alvarez-Villaseñor, Andrea Socorro; Cortés-Flores, Ana Olivia; González-Ojeda, Alejandro

    2015-06-07

    To determine whether or not the use of antioxidant supplementation aids in the prevention of post- endoscopic retrograde cholangiopancreatography pancreatitis. A systematic review of randomized controlled trials (RCTs) was made to evaluate the preventive effect of prophylactic antioxidant supplementation in post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). The inclusion criteria included: acute post-endoscopic retrograde cholangiopancreatography pancreatitis in adults; randomized clinical trials with the use of any antioxidant as an intervention compared with placebo, to reduce PEP. The outcome measure was the incidence and severity of PEP. Twelve RCTs involving 3110 patients since 1999 were included. The antioxidants used were selenite, β-carotene, and pentoxifylline (each one in one trial), N-acetylcysteine (NAC) in three trials, and allopurinol in six trials. The group of patients treated with NAC received different doses; either oral or intravenous, and allopurinol-treated patients received five different oral doses in two different administration periods. The results are expressed with raw numbers, proportions, as well as mean and standard deviations. The incidence of pancreatitis between groups was analyzed with Pearson's χ(2) test or Fisher's exact test (F). The main outcome is expressed as relative risks and 95%CI. The incidence of pancreatitis in all antioxidant treatment groups was 8.6%, whereas it was 9.7% in the control group. The antioxidants used were selenite, β-carotene, and pentoxifylline (each one in one trial), NAC in three trials, and allopurinol in six trials. In allopurinol trials, three different dosifications were used; two trials reported a low dosage (of less than 400 mg), two trials reported a moderate dose (600 mg) and the remaining two employed higher doses (more than 900 mg). Supplementation was not associated with a significant reduction in the incidence of PEP [relative risk (RR) = 0.93; 95%CI: 0.82-1.06; P

  20. M1 ipRGCs Influence Visual Function through Retrograde Signaling in the Retina

    PubMed Central

    Prigge, Cameron L.; Yeh, Po-Ting; Liou, Nan-Fu; Lee, Chi-Chan; You, Shih-Feng; Liu, Lei-Lei; McNeill, David S.; Chew, Kylie S.; Hattar, Samer

    2016-01-01

    Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs, with five subtypes named M1–M5) are a unique subclass of RGCs with axons that project directly to many brain nuclei involved in non-image-forming functions such as circadian photoentrainment and the pupillary light reflex. Recent evidence suggests that melanopsin-based signals also influence image-forming visual function, including light adaptation, but the mechanisms involved are unclear. Intriguingly, a small population of M1 ipRGCs have intraretinal axon collaterals that project toward the outer retina. Using genetic mouse models, we provide three lines of evidence showing that these axon collaterals make connections with upstream dopaminergic amacrine cells (DACs): (1) ipRGC signaling to DACs is blocked by tetrodotoxin both in vitro and in vivo, indicating that ipRGC-to-DAC transmission requires voltage-gated Na+ channels; (2) this transmission is partly dependent on N-type Ca2+ channels, which are possibly expressed in the axon collateral terminals of ipRGCs; and (3) fluorescence microscopy reveals that ipRGC axon collaterals make putative presynaptic contact with DACs. We further demonstrate that elimination of M1 ipRGCs attenuates light adaptation, as evidenced by an impaired electroretinogram b-wave from cones, whereas a dopamine receptor agonist can potentiate the cone-driven b-wave of retinas lacking M1 ipRGCs. Together, the results strongly suggest that ipRGCs transmit luminance signals retrogradely to the outer retina through the dopaminergic system and in turn influence retinal light adaptation. SIGNIFICANCE STATEMENT Melanopsin-expressing intrinsically photosensitive retinal ganglion cells (ipRGCs) comprise a third class of retinal photoreceptors that are known to mediate physiological responses such as circadian photoentrainment. However, investigation into whether and how ipRGCs contribute to vision has just begun. Here, we provide convergent anatomical and

  1. Impairment of Retrograde Neuronal Transport in Oxaliplatin-Induced Neuropathy Demonstrated by Molecular Imaging

    PubMed Central

    Hobbs, Brian P.; Bredow, Sebastian

    2012-01-01

    Background and Purpose The purpose of our study was to utilize a molecular imaging technology based on the retrograde axonal transport mechanism (neurography), to determine if oxaliplatin-induced neurotoxicity affects retrograde axonal transport in an animal model. Materials and Methods Mice (n = 8/group) were injected with a cumulative dose of 30 mg/kg oxaliplatin (sufficient to induce neurotoxicity) or dextrose control injections. Intramuscular injections of Tetanus Toxin C-fragment (TTc) labeled with Alexa 790 fluorescent dye were done (15 ug/20 uL) in the left calf muscles, and in vivo fluorescent imaging performed (0–60 min) at baseline, and then weekly for 5 weeks, followed by 2-weekly imaging out to 9 weeks. Tissues were harvested for immunohistochemical analysis. Results With sham treatment, TTc transport causes fluorescent signal intensity over the thoracic spine to increase from 0 to 60 minutes after injection. On average, fluorescence signal increased 722%+/−117% (Mean+/−SD) from 0 to 60 minutes. Oxaliplatin treated animals had comparable transport at baseline (787%+/−140%), but transport rapidly decreased through the course of the study, falling to 363%+/−88%, 269%+/−96%, 191%+/−58%, 121%+/−39%, 75%+/−21% with each successive week and stabilizing around 57% (+/−15%) at 7 weeks. Statistically significant divergence occurred at approximately 3 weeks (p≤0.05, linear mixed-effects regression model). Quantitative immuno-fluorescence histology with a constant cutoff threshold showed reduced TTc in the spinal cord at 7 weeks for treated animals versus controls (5.2 Arbitrary Units +/−0.52 vs 7.1 AU +/−1.38, p<0.0004, T-test). There was no significant difference in neural cell mass between the two groups as shown with NeuN staining (10.2+/−1.21 vs 10.5 AU +/−1.53, p>0.56, T-test). Conclusion We show–for the first time to our knowledge–that neurographic in vivo molecular imaging can demonstrate imaging changes in a model of

  2. Recanalization strategy of retrograde angioplasty in patients with coronary chronic total occlusion -analysis of 24 cases, focusing on technical aspects and complications.

    PubMed

    Lee, Nae-Hee; Seo, Hye-Sun; Choi, Jae-Hyuk; Suh, Jon; Cho, Yoon Haeng

    2010-10-08

    Retrograde approach through collateral channels was recently proposed to increase the success rate of percutaneous coronary intervention (PCI) for coronary chronic total occlusion (CTO), but this approach is still an incompletely described technique. We analyzed 24 cases of retrograde PCI for CTO, which were done from July 2006 to April 2008. Septal collaterals were more frequently used than epicardial collaterals (75% vs. 25%), without showing statistical differences in wire passage rate according to the size or location of the collaterals. Once the retrograde wire successfully crossed collateral (18/24 cases), CTO lesion was successfully crossed in all cases by using 4 different kinds of techniques: retrograde wire crossing (44%), kissing wire (22%), controlled antegrade and retrograde subintimal tracking (22%), and reverse controlled antegrade and retrograde subintimal tracking (11%). Among them, successful recanalization was achieved in 17 cases, yielding 71% retrograde PCI success rate. In failed cases with retrograde approach, 4 cases were recanalized by switching to antegrade approach. Thus, total PCI success rate was 88% (21/24 cases). There were several cases of unexpected complications mainly related to collateral-donor artery without in-hospital major adverse cardiac events (MACE). During clinical follow-up (median 10.3 months), overall MACE rate was 18% in the successful retrograde PCI group. The retrograde approach can improve the success rate with PCI for CTO. However, strict case selection with systemized approach is essential due to the technical complexities accompanied by the potential risk of unexpected complications. Copyright © 2009 Elsevier B.V. All rights reserved.

  3. Management of urine leak after laparoscopic cyst decortication with retrograde endoscopic fibrin glue application and ureteral stent placement.

    PubMed

    Chen, Mang L; Tomaszewski, Jeffrey J; Matoka, Derek J; Ost, Michael C

    2011-01-01

    Urine leakage is an uncommon complication after renal cyst decortication that typically resolves with adequate drainage. With prolonged large volume urine leakage from a perinephric drain, however, consideration for open surgical repair must be taken into account. We present the successful management of persistent urine leakage after laparoscopic cyst decortication with endoscopic retrograde fibrin glue injection and ureteral stent placement.

  4. Integrating bio-prosthetic valves in the Fontan operation - Novel treatment to control retrograde flow in caval veins

    NASA Astrophysics Data System (ADS)

    Vukicevic, Marija; Conover, Timothy; Zhou, Jian; Hsia, Tain-Yen; Figliola, Richard

    2012-11-01

    For a child born with only one functional heart ventricle, the sequence of palliative surgeries typically culminates in the Fontan operation. This procedure is usually successful initially, but leads to later complications, for reasons not fully understood. Examples are respiratory-dependent retrograde flows in the caval and hepatic veins, and increased pulmonary vascular resistance (PVR), hypothesized to be responsible for elevated pressure in the liver and disease of the liver and intestines. Here we study the parameters responsible for retrograde flows in the inferior vena cava (IVC) and hepatic vein (HV), and investigate two novel interventions to control retrograde flow: implanting either a Medtronic Contegra valved conduit or an Edwards lifescience pericardial aortic valve in the IVC or HV. We performed the experiments in a multi-scale, patient specific mock circuit, with normal and elevated PVR, towards the optimization of the Fontan circulation. The results show that both valves can significantly reduce retrograde flows in the veins, suggesting potential advantages in the treatment of the patients with congenital heart diseases. Fondation Leducq

  5. Structural and functional mapping of Rtg2p determinants involved in retrograde signaling and aging of Saccharomyces cerevisiae

    PubMed Central

    Rios-Anjos, Rafaela Maria; Camandona, Vittoria de Lima; Bleicher, Lucas

    2017-01-01

    In Saccharomyces cerevisiae mitochondrial dysfunction induces retrograde signaling, a pathway of communication from mitochondria to the nucleus that promotes a metabolic remodeling to ensure sufficient biosynthetic precursors for replication. Rtg2p is a positive modulator of this pathway that is also required for cellular longevity. This protein belongs to the ASKHA superfamily, and contains a putative N-terminal ATP-binding domain, but there is no detailed structural and functional map of the residues in this domain that accounts for their contribution to retrograde signaling and aging. Here we use Decomposition of Residue Correlation Networks and site-directed mutagenesis to identify Rtg2p structural determinants of retrograde signaling and longevity. We found that most of the residues involved in retrograde signaling surround the ATP-binding loops, and that Rtg2p N-terminus is divided in three regions whose mutants have different aging phenotypes. We also identified E137, D158 and S163 as possible residues involved in stabilization of ATP at the active site. The mutants shown here may be used to map other Rtg2p activities that crosstalk to other pathways of the cell related to genomic stability and aging. PMID:28472157

  6. Structural and functional mapping of Rtg2p determinants involved in retrograde signaling and aging of Saccharomyces cerevisiae.

    PubMed

    Rios-Anjos, Rafaela Maria; Camandona, Vittoria de Lima; Bleicher, Lucas; Ferreira-Junior, Jose Ribamar

    2017-01-01

    In Saccharomyces cerevisiae mitochondrial dysfunction induces retrograde signaling, a pathway of communication from mitochondria to the nucleus that promotes a metabolic remodeling to ensure sufficient biosynthetic precursors for replication. Rtg2p is a positive modulator of this pathway that is also required for cellular longevity. This protein belongs to the ASKHA superfamily, and contains a putative N-terminal ATP-binding domain, but there is no detailed structural and functional map of the residues in this domain that accounts for their contribution to retrograde signaling and aging. Here we use Decomposition of Residue Correlation Networks and site-directed mutagenesis to identify Rtg2p structural determinants of retrograde signaling and longevity. We found that most of the residues involved in retrograde signaling surround the ATP-binding loops, and that Rtg2p N-terminus is divided in three regions whose mutants have different aging phenotypes. We also identified E137, D158 and S163 as possible residues involved in stabilization of ATP at the active site. The mutants shown here may be used to map other Rtg2p activities that crosstalk to other pathways of the cell related to genomic stability and aging.

  7. Balloon-occluded retrograde transvenous obliteration of varices: focusing on the portal hemodynamics and the recent techniques.

    PubMed

    Hirota, Shozo; Kobayashi, Kaoru; Kako, Yasukazu; Takaki, Haruyuki; Yamakado, Koichiro

    2017-09-05

    To evaluate the recent topics of Ballloon-occluded retrograde trasnvenous obliteration(B-RTO). We overviewed the recent scientific papers regarding B-RTO. B-RTO is a treatment method for occluding varices retrogradely using a sclerosing agent under balloon occlusion of a major draining vein. It has been recognized as an effective treatment method for gastric varices. Hepatic function reserve is improved and liver volume is increased after B-RTO. In recent years, various technical options, such as plug-assisted retrograde transvenous obliteration, coil-assisted retrograde transvenous obliteration, or foam B-RTO, have also been reported. In performing B-RTO, portal hemodynamics must be thoroughly examined radiologically. Judging the classification of the grade of collateral venous hemodynamics is important to select the appropriate embolization technique of B-RTO and to successfully occlude varices. Finally, the word "portosystemic shunt syndrome" has been proposed and the condition should be considered while selecting a treatment for gastric varices. B-RTO is effective for gastrointestinal varices and portosystemic shunts.

  8. Influence of acyl chain lengths in mono- and diacyl-sn-glycerophosphatidylcholine on gelatinization and retrogradation of starch.

    PubMed

    Siswoyo, T A; Morita, N

    2001-10-01

    The influence of starch with 1- or 2-monoacyl-sn-glycerophosphatidylcholine (GPC) having various chain lengths of fatty acids on gelatinization and retrogradation of starch was studied by the measurement of starch-GPC complex formation, complexing index, and differential scanning calorimetry. The addition of GPC to the starch sample slightly increased the blue value and lambda(max) with increasing chain length of GPC but decreased the phosphorus content and complexing index. The gelatinization onset and peak temperatures of starch complexes increased significantly with increasing chain length, but the enthalpies were statistically lower, except for the treatment with 1,2-distearoyl-sn-GPC when compared with that of the control. Among GPC (di and mono), 1- and 2-monomyristoyl-sn-GPC showed the highest complexing ability, whereas the complexing ability of the GPC decreased with the increasing chain length. According to the Avrami equation, the retrogradation rate (k, day(-1)) of starch was slower than that of the control, whereas the retrogradation rates of 1- and 2-monomyristoyl-sn-GPC were slowest among the GPCs. The positive linear relationship between k and the number of acyl groups of GPC suggests that a GPC with a shorter chain length could retard the retrogradation of starch during storage.

  9. Revascularization of a central vein total occlusion via antegrade and retrograde approach in a patient with hemodialysis access.

    PubMed

    Fang, Hsiu-Yu; Hsieh, Yuan-Kai; Wu, Chiung-Jen

    2010-12-01

    The occurrence of central vein total occlusion results in upper arm edema, pain, and hemodialysis access failure in uremic patient. Previous studies have proven the effectiveness of percutaneous balloon angioplasty for central vein total occlusion. Here, we report a rare case of successful revascularization of central vein total occlusion via antegrade and retrograde approach. Copyright © 2010 Wiley-Liss, Inc.

  10. Hippocampus and Retrograde Amnesia in the Rat Model: A Modest Proposal for the Situation of Systems Consolidation

    PubMed Central

    Sutherland, Robert J.; Sparks, Fraser; Lehmann, Hugo

    2010-01-01

    The properties of retrograde amnesia after damage to the hippocampus have been explicated with some success using a rat model of human medial temporal lobe amnesia. We review the results of this experimental work with rats focusing on several areas of consensus in this growing literature. We evaluate the theoretically significant hypothesis that hippocampal retrograde amnesia normally exhibits a temporal gradient, affecting recent, but sparing remote memories. Surprisingly, the evidence does not provide much support for the idea that there is a lengthy process of systems consolidation following a learning episode. Instead, recent and remote memories tend to be equally affected. The extent of damage to the hippocampus is a significant factor in this work since it is likely that spared hippocampal tissue can support at least partial memory retrieval. With extensive hippocampal damage gradients are flat or, in the case of memory tasks with flavour/odour retrieval cues, the retrograde amnesia covers a period of about 1 – 3 days. There is consistent evidence that at the time of learning the hippocampus interferes with or overshadows memory acquisition by other systems. This contributes to the breadth and severity of retrograde amnesia relative to anterograde amnesia in the rat. The fact that multiple, distributed learning episodes can overcome this overshadowing is consistent with a parallel dual-store theory or a Distributed Reinstatement Theory in which each learning episode triggers a short period of memory replay that provides a brief hippocampal-dependent systems consolidation. PMID:20430043

  11. The postsynaptic t-SNARE Syntaxin 4 controls traffic of Neuroligin 1 and Synaptotagmin 4 to regulate retrograde signaling

    PubMed Central

    Harris, Kathryn P; Zhang, Yao V; Piccioli, Zachary D; Perrimon, Norbert; Littleton, J Troy

    2016-01-01

    Postsynaptic cells can induce synaptic plasticity through the release of activity-dependent retrograde signals. We previously described a Ca2+-dependent retrograde signaling pathway mediated by postsynaptic Synaptotagmin 4 (Syt4). To identify proteins involved in postsynaptic exocytosis, we conducted a screen for candidates that disrupted trafficking of a pHluorin-tagged Syt4 at Drosophila neuromuscular junctions (NMJs). Here we characterize one candidate, the postsynaptic t-SNARE Syntaxin 4 (Syx4). Analysis of Syx4 mutants reveals that Syx4 mediates retrograde signaling, modulating the membrane levels of Syt4 and the transsynaptic adhesion protein Neuroligin 1 (Nlg1). Syx4-dependent trafficking regulates synaptic development, including controlling synaptic bouton number and the ability to bud new varicosities in response to acute neuronal stimulation. Genetic interaction experiments demonstrate Syx4, Syt4, and Nlg1 regulate synaptic growth and plasticity through both shared and parallel signaling pathways. Our findings suggest a conserved postsynaptic SNARE machinery controls multiple aspects of retrograde signaling and cargo trafficking within the postsynaptic compartment. DOI: http://dx.doi.org/10.7554/eLife.13881.001 PMID:27223326

  12. Hippocampus and Retrograde Amnesia in the Rat Model: A Modest Proposal for the Situation of Systems Consolidation

    ERIC Educational Resources Information Center

    Sutherland, Robert J.; Sparks, Fraser T.; Lehmann, Hugo

    2010-01-01

    The properties of retrograde amnesia after damage to the hippocampus have been explicated with some success using a rat model of human medial temporal lobe amnesia. We review the results of this experimental work with rats focusing on several areas of consensus in this growing literature. We evaluate the theoretically significant hypothesis that…

  13. Periapical surgery using the ultrasound technique and silver amalgam retrograde filling. A study of 71 teeth with 100 canals.

    PubMed

    Martí-Bowen, Eva; Peñarrocha-Diago, Miguel; García-Mira, Berta

    2005-04-01

    Periapical surgery using ultrasound allows the treatment of root canals of difficult access, with the sacrifice of little root tissue. As a result, periapical disorders which were condemned to treatment failure in the past can now be dealt with successfully. In 71 teeth presenting 100 root canals treated with ultrasound and subjected to retrograde filling with silver amalgam, the course and short-term success of management was evaluated in relation to lesion size, the magnitude of apical resection, and the size of the retrograde filling cavity. The duration of follow-up was one year, with post-treatment controls after 6 and 12 months. After 6 months, the percentage clinical and radiological success was 92% and 58%, respectively. One year after periapical surgery the corresponding percentages were 95% and 80%. Global success after 6 months was 63%, versus 84.2% after 12 months. No statistically significant relation was observed between treatment success and the size of the periapical lesion, the amount of apex resected, or the size of retrograde filling. Periapical surgery using ultrasound and retrograde filling with silver amalgam affords a high success rate after 12 months.

  14. Treatment of hepatic encephalopathy by retrograde transcaval coil embolization of an ileal vein-to-right gonadal vein portosystemic shunt

    SciTech Connect

    Nishie, Akihiro; Yoshimitsu, Kengo; Honda, Hiroshi; Kaneko, Kuniyuki; Kuroiwa, Toshiro; Fukuya, Tatsuro; Irie, Hiroyuki; Ninomiya, Toshiharu; Yoshimitsu, Takahiro; Hirakata, Hideki; Okuda, Seiya; Masuda, Kouji

    1997-05-15

    A 43-year-old non-cirrhotic woman suffered from encephalopathy caused by an extrahepatic portosystemic shunt between the ileal vein and inferior vena cava via the right gonadal vein. Percutaneous transcatheter embolization with stainless steel coils was performed by the retrograde systemic venous approach. Encephalopathy improved dramatically.

  15. Effect of temperature-cycled retrogradation on in vitro digestibility and structural characteristics of waxy potato starch.

    PubMed

    Xie, Yao-Yu; Hu, Xiao-Pei; Jin, Zheng-Yu; Xu, Xue-Ming; Chen, Han-Qing

    2014-06-01

    The effects of temperature-cycled retrogradation treatment on the structural characteristics and in vitro digestibility of waxy potato starch were investigated in this study. The results showed that the maximum yield of slowly digestible starch (SDS) in waxy potato starch reached 38.63% by retrogradation treatment under temperature cycles of 4/25°C for 3 days with an interval of 24h. The starch products prepared under the temperature cycles of 4/25°C exhibited a narrower melting temperature range (Tc-To), a higher melting enthalpy (ΔH) and a higher IR absorbance ratio (1047cm(-1)/1022cm(-1)) than that prepared at a constant temperature of 25°C. Compared to native starch, X-ray diffraction pattern of treated starch was altered from B-type to C-type. Furthermore, the relative crystallinity of the starch products prepared under temperature-cycled retrogradation was the highest. This study suggests that more imperfect crystallites are formed in the crystalline matrix under temperature-cycled retrogradation, resulting in a high yield of SDS.

  16. Voltage-gated calcium and sodium channels mediate Sema3A retrograde signaling that regulates dendritic development.

    PubMed

    Yamashita, Naoya; Aoki, Reina; Chen, Sandy; Jitsuki-Takahashi, Aoi; Ohura, Shunsuke; Kamiya, Haruyuki; Goshima, Yoshio

    2016-01-15

    Growing axons rely on local signaling at the growth cone for guidance cues. Semaphorin3A (Sema3A), a secreted repulsive axon guidance molecule, regulates synapse maturation and dendritic branching. We previously showed that local Sema3A signaling in the growth cones elicits retrograde retrograde signaling via PlexinA4 (PlexA4), one component of the Sema3A receptor, thereby regulating dendritic localization of AMPA receptor GluA2 and proper dendritic development. In present study, we found that nimodipine (voltage-gated L-type Ca(2+) channel blocker) and tetrodotoxin (TTX; voltage-gated Na(+) channel blocker) suppress Sema3A-induced dendritic localization of GluA2 and dendritic branch formation in cultured hippocampal neurons. The local application of nimodipine or TTX to distal axons suppresses retrograde transport of Venus-Sema3A that has been exogenously applied to the distal axons. Sema3A facilitates axonal transport of PlexA4, which is also suppressed in neurons treated with either TTX or nimodipine. These data suggest that voltage-gated calcium and sodium channels mediate Sema3A retrograde signaling that regulates dendritic GluA2 localization and branch formation.

  17. Actin retrograde flow and actomyosin II arc contraction drive receptor cluster dynamics at the immunological synapse in Jurkat T cells

    PubMed Central

    Yi, Jason; Wu, Xufeng S.; Crites, Travis; Hammer, John A.

    2012-01-01

    Actin retrograde flow and actomyosin II contraction have both been implicated in the inward movement of T cell receptor (TCR) microclusters and immunological synapse formation, but no study has integrated and quantified their relative contributions. Using Jurkat T cells expressing fluorescent myosin IIA heavy chain and F-tractin—a novel reporter for F-actin—we now provide direct evidence that the distal supramolecular activation cluster (dSMAC) and peripheral supramolecular activation cluster (pSMAC) correspond to lamellipodial (LP) and lamellar (LM) actin networks, respectively, as hypothesized previously. Our images reveal concentric and contracting actomyosin II arcs/rings at the LM/pSMAC. Moreover, the speeds of centripetally moving TCR microclusters correspond very closely to the rates of actin retrograde flow in the LP/dSMAC and actomyosin II arc contraction in the LM/pSMAC. Using cytochalasin D and jasplakinolide to selectively inhibit actin retrograde flow in the LP/dSMAC and blebbistatin to selectively inhibit actomyosin II arc contraction in the LM/pSMAC, we demonstrate that both forces are required for centripetal TCR microcluster transport. Finally, we show that leukocyte function–associated antigen 1 clusters accumulate over time at the inner aspect of the LM/pSMAC and that this accumulation depends on actomyosin II contraction. Thus actin retrograde flow and actomyosin II arc contraction coordinately drive receptor cluster dynamics at the immunological synapse. PMID:22219382

  18. Temporary Capture of Asteroids by a Planet: Dependence of Prograde/Retrograde Capture on Asteroids’ Semimajor Axes

    NASA Astrophysics Data System (ADS)

    Higuchi, A.; Ida, S.

    2016-01-01

    We have investigated the dependence of the prograde/retrograde temporary capture of asteroids by a planet on their original heliocentric semimajor axes through analytical arguments and numerical orbital integrations in order to discuss the origins of irregular satellites of giant planets. We found that capture is mostly retrograde for the asteroids near the planetary orbit and is prograde for those from farther orbits. An analytical investigation reveals the intrinsic dynamics of these dependences and gives boundary semimajor axes for the change in prograde/retrograde capture. The numerical calculations support the idea of deriving analytical formulae and confirm their dependence. Our numerical results show that the capture probability is much higher for bodies from the inner region than for outer ones. These results imply that retrograde irregular satellites of Jupiter are most likely captured bodies from the nearby orbits of Jupiter that may have the same origin as Trojan asteroids, while prograde irregular satellites originate from far inner regions such as the main-belt asteroid region.

  19. Hippocampus and Retrograde Amnesia in the Rat Model: A Modest Proposal for the Situation of Systems Consolidation

    ERIC Educational Resources Information Center

    Sutherland, Robert J.; Sparks, Fraser T.; Lehmann, Hugo

    2010-01-01

    The properties of retrograde amnesia after damage to the hippocampus have been explicated with some success using a rat model of human medial temporal lobe amnesia. We review the results of this experimental work with rats focusing on several areas of consensus in this growing literature. We evaluate the theoretically significant hypothesis that…

  20. Successful management of infertility due to retrograde ejaculation using assisted reproductive technologies: a report of two cases.

    PubMed

    Zhao, Y; Garcia, J; Jarow, J P; Wallach, E E

    2004-01-01

    Although retrograde ejaculation is a relatively uncommon cause of infertility, it is nonetheless the most common cause of ejaculatory dysfunction. Retrograde ejaculation is characterized by either all or part of the seminal fluid going into the bladder. The initial management of patients with ejaculatory dysfunction is medical therapy. In couples who have failed medical therapy, assisted reproductive techniques using sperm harvested from either the urine or the male reproductive tract would be the ultimate option. We report successful management of two couples, both men with advanced age and complete retrograde ejaculation, by intrauterine insemination in one and in vitro fertilization (IVF) using intracytoplasmic sperm injection (ICSI) in the other using sperm harvested from urine. The cases reported herein suggest that male infertility due to retrograde ejaculation may be successfully treated in men significantly older than the usual reproductive age and that traditional methods of hydration and urine alkalinization allow for the successful recovery of fertile sperm for ART. The selection of the method of ART must be individualized to the needs of each couple based upon both male and female factors.