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Sample records for aortic caged ball-valve

  1. Long-term follow-up of unusual ball-valve aortic substitute.

    PubMed

    Shumacker, H B; Isch, J H; Jolly, W W

    1978-08-01

    On March 19, 1962, prior to the availability of Starr-Edwards ball-valve prostheses for aortic substitution, a mitral valve turned upside down was implanted for marked calcific aortic stenosis. It worked well and the patient was in good health for 15 years. Late annular calcification and loosening of sutures with marked perivalvular regurgitation made valve replacement necessary 16 years after operation. The original valve was perfectly preserved. PMID:682654

  2. Ball valve extractor

    DOEpatents

    Herndon, Charles; Brown, Roger A.

    2002-01-01

    An apparatus and process for removing a ball valve is provided. The ball valve removal tool provides a handle sliding along the length of a shaft. One end of the shaft is secured within an interior cavity of a ball valve while the opposite end of the shaft defines a stop member. By providing a manual sliding force to the handle, the handle impacts the stop member and transmits the force to the ball valve. The direction of the force is along the shaft of the removal tool and disengages the ball valve from the ball valve housing.

  3. Stemless ball valve

    NASA Technical Reports Server (NTRS)

    Burgess, Kevin (Inventor); Yakos, David (Inventor); Walthall, Bryan (Inventor)

    2011-01-01

    A stemless ball valve comprising two flanges and a ball with a channel, two axis pins and two travel pins. One end of each axis and travel pin is fixedly attached to the ball, and the other end of each axis pin is lodged into a notch in the first or second flange such that the axis pin is allowed to rotate in the notch. The guide sleeve comprises two channels, and one end of each travel pin is situated within one of the two channels in the guide sleeve. An outer magnetic cartridge causes the inner magnetic cartridge and guide sleeve to rotate, and when the guide sleeve rotates, the travel pins move up and down within the channels in the guide sleeve. The movement of the travel pins within the channels in the guide sleeve causes the ball to rotate, thereby opening and closing the ball valve.

  4. Stemless Ball Valve

    NASA Technical Reports Server (NTRS)

    Burgess, Robert K.; Yakos, David; Walthall, Bryan

    2012-01-01

    This invention utilizes a new method of opening and closing a ball valve. Instead of rotating the ball with a perpendicular stem (as is the case with standard ball valves), the ball is rotated around a fixed axis by two guide pins. This innovation eliminates the leak point that is present in all standard ball valves due to the penetration of an actuation stem through the valve body. The VOST (Venturi Off-Set-Technology) valve has been developed for commercial applications. The standard version of the valve consists of an off-set venturi flow path through the valve. This path is split at the narrowest portion of the venturi, allowing the section upstream from the venturi to be rotated. As this rotation takes place, the venturi becomes restricted as one face rotates with respect to the other, eventually closing off the flow path. A spring-loaded seal made of resilient material is embedded in the upstream face of the valve, making a leak-proof seal between the faces; thus a valve is formed. The spring-loaded lip seal is the only seal that can provide a class six, or bubble-tight, seal against the opposite face of the valve. Tearing action of the seal by high-velocity gas on this early design required relocation of the seal to the downstream face of the valve. In the stemless embodiment of this valve, inner and outer magnetic cartridges are employed to transfer mechanical torque from the outside of the valve to the inside without the use of a stem. This eliminates the leak path caused by the valve stems in standard valves because the stems penetrate through the bodies of these valves.

  5. Quartz ball valve

    NASA Technical Reports Server (NTRS)

    Goetz, C.; Ingle, W. M. (Inventor)

    1980-01-01

    A ball valve particularly suited for use in the handling of highly corrosive fluids is described. It is characterized by a valve housing formed of communicating segments of quartz tubing, a pair of communicating sockets disposed in coaxial alignment with selected segments of tubing for establishing a pair of inlet ports communicating with a common outlet port, a ball formed of quartz material supported for displacement between the sockets and configured to be received alternately thereby, and a valve actuator including a rod attached to the ball for selectively displacing the ball relative to each of the sockets for controlling fluid flow through the inlet ports.

  6. Stemless ball valve

    NASA Technical Reports Server (NTRS)

    Burgess, Kevin (Inventor); Yakos, David (Inventor); Walthall, Bryan (Inventor)

    2012-01-01

    A stemless ball valve comprising: a right flange; left flange; ball with an axis pin and two travel pins; ball seal on either side of the ball; guide sleeve with inner walls comprising two channels; cartridge guide holder; inner magnetic cartridge; and outer magnetic cartridge. The ball is situated inside of the guide sleeve, and a travel pin is located in each of the two channels. The guide sleeve is situated inside of the cartridge guide holder, which is located adjacent to and outside of the inner magnetic cartridge and secured to the inner magnetic cartridge such that when the inner magnetic cartridge rotates, the cartridge guide holder also rotates. The cartridge guide holder is secured to the guide sleeve such that when the cartridge guide holder rotates, the travel pins move within the channels in the inner walls of the guide sleeve, thereby causing the ball to rotate.

  7. Segmented ball valve is easy to open and close

    NASA Technical Reports Server (NTRS)

    Prono, E.; Shinault, L. H.; Speisman, C.

    1966-01-01

    Segmented ball valve and flowmeter in the same spherical housing provide a valve that will handle large fluid volume without bulkiness and weight of blade valves or conventional ball valves. The valve is easily opened or closed and the flowmeter remains stationary, so errors are eliminated.

  8. 16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEENINCH BALL VALVE. Looking ...

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

    16. DETAIL SHOWING LIQUID OXYGEN TANK FOURTEEN-INCH BALL VALVE. Looking southwest. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  9. 17. DETAIL, FOURTEENINCH LIQUID OXYGEN BALL VALVE. Looking south southeast. ...

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

    17. DETAIL, FOURTEEN-INCH LIQUID OXYGEN BALL VALVE. Looking south southeast. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  10. Ball valve regulator reduces noise at regulating stations

    SciTech Connect

    Hogan, M.P.

    1998-10-01

    In recent years, there has been growing concern within the natural gas industry regarding the effect regulating stations have on their surrounding environments. To reduce excessive noise and pollution, many gas distribution and transmission companies have begun utilizing equipment which reduces environmental impact. The below grade ball valve regulator is a prime example of this environment-friendly equipment. Its high capacity, control capabilities, rangeability, and dependability makes the below grade ball valve regulator the preferred method for controlling natural gas flow. Its long-term reliability makes the below grade ball valve regulator the ideal method of, not only maintaining superior flow characteristics, but also of greatly reducing noise created in the station facilities.

  11. Whitey SCHe Ball Valves Provide Test Port Isolation

    SciTech Connect

    MISKA, C.R.

    2000-09-15

    These valves are 1/4 inch ball valves fabricated of 316 stainless steel. Packing is TFE (standard). They are used as normally closed isolation valves for test ports in the SCHe System between the gage root valve and the pressure indicator.

  12. High performance, severe service critical extraction ball valves

    SciTech Connect

    Barrette, E.J.

    1995-12-31

    Securaseal high performance, severe service, critical extraction metal seated ball valves are required to resist extremes of wear, corrosion, and erosion at extreme Cv flow values, pressure, and temperature. The valves` wetted surfaces are often in contact with acids, bases (caustics), slurries, and high velocity solids. The Securaseal metal seated ball valves must maintain very low or no leakage rate,s and not fail between routine maintenance periods s the valves endure all of these extreme operating conditions.Securaseal metal seated ball valves incorporate numerous design features to offer superior performance in these environments. Among these features are customized HVOF and plasma sprayed coatings applied exclusively by Engelhard Surface Technologies. Securacoat coatings have been developed to provide repeatable, high reliable coatings which are often customized for a client`s particular application/environment. Securamax utilizes the repeatable properties of the coatings by incorporating these properties into their valve design using extensive FEA including operating simulations to ensure validated stress levels and that the coating contact stresses are within the coating`s performance specifications. Numerous examples of valve/coating performance in severe service environments such as chemical plants, gold mining, Synfuels and others will be discussed.

  13. Space Shuttle Orbital Maneuvering Subsystem (OMS) Engine Propellant Leakage Ball-Valve Shaft Seals

    NASA Technical Reports Server (NTRS)

    Lueders, Kathy; Buntain, Nick; Fries, Joseph (Technical Monitor)

    1999-01-01

    Evidence of propellant leakage across ball-valve shaft seals has been noted during the disassembly of five flight engines and one test engine at the NASA Lyndon B. Johnson Space Center, White Sands Test Facility. Based on data collected during the disassembly of these five engines, the consequences of propellant leakage across the ball-valve shaft seals can be divided into four primary areas of concern: Damage to the ball-valve pinion shafts, damage to sleeved bearings inside the ball-valve and actuator assemblies, degradation of the synthetic rubber o-rings used in the actuator assemblies, and corrosion and degradation to the interior of the actuator assemblies. The exact time at which leakage across the ball-valve shaft seals occurs has not been determined, however, the leakage most likely occurs during engine firings when, depending on the specification used, ball-valve cavity pressures range as high as 453 to 550 psia. This potential pressure range for the ball-valve cavities greatly exceeds the acceptance leakage test pressure of 332 psia. Since redesign and replacement of the ball-valve shaft seals is unlikely, the near term solution to prevent damage that occurs from shaft-seal leakage is to implement a routine overhaul and maintenance program for engines in the fleet. Recommended repair, verification, and possible preventative maintenance measures are discussed in the paper.

  14. Fatal endotracheal tube obstruction due to the ball valve effect.

    PubMed

    Woittiez, Karen Jante; Woittiez, Arend Jan Jacob

    2015-01-01

    In patients suffering from pulmonary haemorrhage, or in patients who recently received a tracheostomy, acute occlusion of the endotracheal tube due to a blood clot is a rare, but well-known complication. Acute and complete occlusion of the tube is easily recognisable. There are various methods of removing the obstructive clot, such as using a bronchoscope with forceps, topical thrombolysis, saline lavage and suctioning. There are no guidelines concerning preventive routine bronchoscopic lavage. When there is a partial obstruction of the endotracheal tube, ventilation is possible, although high inspiratory pressures are necessary. If the clot functions as a ball valve ventil, raised intrathoracic pressure will cause right-sided heart failure or tension pneumothorax. It is important to recognise a partially obstructed tube in time and remove the obstruction. PMID:25618886

  15. Numerical simulation and analysis of ball valve three-dimensional flow based on CFD

    NASA Astrophysics Data System (ADS)

    Zhang, S. C.; Zhang, Y. L.; Fang, Z. M.

    2012-11-01

    The new rotor oil-gas mixture pump that added ball valves in its export is a kind of innovative products, which can better adapt to the oil and gas mixed condition. In order to explore the rule of flow field in the export ball valve of new rotor oil-gas mixture pump, established the 3 d model of ball valve flow field was established. Using the FLUENT software, combining the standard k-epsilon turbulent model with multiphase flow technology and adopting the SIMPLE algorithm to simulate the 3 d gas-liquid two phase flow field in export ball valve of new rotor oil-gas mixture pump. In the different conditions that the volume of gas rate was 25%, 50%, 75%, through analyzing the velocity field, stress field and the distribution of the liquid and gas with the ball valve open height respectively at 3mm, 5mm, 7mm. Discussed how open height and different volume of gas rate to influence the field in export ball valve in the process of gas-liquid mixing was discussed. The simulation results showed that the greater the open height, the smaller the difference pressure of ball valve; the gap velocity decreasing with the open height increasing. The gas is mainly distributed in the vicinity of the valve ball in the process of gas-liquid mixing. The gas liquid ratio has a little effect on the gap velocity in the same open height. The results showed the flow field forms in the ball valve directly, to a certain degree, it had released the rules of gas-liquid flow in the valve and provided the theoretical guidance for design and optimization of the new rotor oil-gas mixture pump export ball valve.

  16. Difficult Ventilation After Successful Intubation in the Emergency Setting due to a Ball Valve Clot.

    PubMed

    Liberman, Justin S; Weigel, Wade; Neal, Joseph M

    2016-05-15

    The inability to ventilate a patient after successful intubation is a rare but emergent situation and may be caused by obstruction of the endotracheal tube, bilateral tension pneumothorax, esophageal intubation, severe bronchospasm, or mainstem bronchus intubation. We describe an increase in mean airway pressure, inability to ventilate, and loss of cardiac output secondary to a blood clot acting as a ball valve at the end of an endotracheal tube. PMID:26934604

  17. Remotely maintainable top-loading captive ball valve system for ICPP

    SciTech Connect

    Berry, S.M.

    1994-12-31

    A program was undertaken for the remote maintenance of valve boxes at the Idaho Chemical Processing Plant. The remote adaptive features developed for a 3-in. top-loading captive ball valve have been fabricated and thoroughly tested on a prototype 3-in. valve unit located at the RRMTF. Remote disassembly/assembly has been successfully demonstrated on numerous occasions by the RSA group at WINCO. In addition, the remotely detachable valve actuator rod has also been successfully demonstrated on this prototype unit. Approximately 150 valves of several sizes with remote adaptive features based on WINCO`s prototype development by the RSA group are currently being manufactured.

  18. Whitey Swagelok SCHe ball valves Provide Isolation between SCHe Purge Lines C and D and the Process Vent

    SciTech Connect

    MISKA, C.R.

    2000-09-03

    These valves are 1/4 inch ball valves fabricated of 316 stainless steel. Packing is TFE (standard). They provide an isolation function betwen SCHe Purge Line C, (PV-V-*079), and Purge Line D, (PV-V-*080), and the Process Vent.

  19. Whitey Swagelok SCHe Ball Valves Provide Isolation between SCHe Purge Lines C and D and the Process Vent

    SciTech Connect

    MISKA, C.R.

    2000-09-15

    These valves are 1/4 inch ball valves fabricated of 316 stainless steel. Packing is TFE (standard). They provide an isolation function betwen SCHe Purge Line C, (PV-V-*079), and Purge Line D, (PV-V-*080), and the Process Vent.

  20. HVOF Coating Case Study for Power Plant Process Control Ball Valve Application

    NASA Astrophysics Data System (ADS)

    Vernhes, Luc; Lee, David A.; Poirier, Dominique; Li, Duanjie; Klemberg-Sapieha, Jolanta E.

    2013-10-01

    This case study is the result of an investigation on HVOF 80/20 Cr3C2-NiCr coating failure of on-off metal-seated ball valve (MSBV) used in supercritical steam lines in a power plant and solution. HVOF 80/20 Cr3C2-NiCr coating is used to protect thousands of MSBVs without incident. However, in this case, the valves are challenged with exposure to rapid high-pressure and -temperature variations resulting in a unique situation where the coating experiences cracking and cohesive failure. It was found that carbide precipitation is a major factor causing embrittlement of the coating. Once the coating toughness and ductility is reduced, thermal, mechanical, and residual stresses can initiate and propagate cracks more easily, causing coating failure when exposed to thermal shock. To alleviate the above mentioned issues, possible coating alternatives were then evaluated.

  1. Anesthetic Management for Laser Excision of Ball-Valving Laryngeal Masses

    PubMed Central

    Bruins, Benjamin B.; Mirza, Natasha; Gomez, Ernest; Atkins, Joshua H.

    2015-01-01

    A 47-year-old obese woman with GERD and COPD presents for CO2-laser excision of bilateral vocal fold masses. She had a history of progressive hoarseness and difficulty in breathing. Nasopharyngeal laryngoscopy revealed large, mobile, bilateral vocal cord polyps that demonstrated dynamic occlusion of the glottis. We describe the airway and anesthetic management of this patient with a topicalized C-MAC video laryngoscopic intubation using a 4.5 mm Xomed Laser Shield II endotracheal tube. We examine the challenges of anesthetic management unique to the combined circumstances of a ball-valve lesion and the need for a narrow-bore laser compatible endotracheal tube. PMID:26090238

  2. Understanding how brass ball valves passing certification testing can cause elevated lead in water when installed.

    PubMed

    Triantafyllidou, Simoni; Raetz, Meredith; Parks, Jeffrey; Edwards, Marc

    2012-06-15

    The lead leaching potential of new brass plumbing devices has come under scrutiny as a significant source of lead in drinking water (>300 μg/L) of new buildings around the world. Experiments were conducted using ball valves that were sold as certified and known to have caused problems in practice, in order to better understand how installed products could create such problems, even if they passed "leaching tests" such as National Sanitation Foundation (NSF) Standard 61 Section 8. Diffusion of lead from within the device into water when installed can increase lead leaching by orders of magnitude relative to results of NSF testing, which once only required exposure of very small volumes of water within the device. "Normalization" of the lead-in-water result tended to produce estimates of lead concentration that were much lower than actual lead measured at the tap. Finally, the presence of flux could also dramatically increase lead leaching, whereas high water velocity had relatively little effect. PMID:22520861

  3. Aortic angiography

    MedlinePlus

    ... with the aorta or its branches, including: Aortic aneurysm Aortic dissection Congenital (present from birth) problems AV ... Abnormal results may be due to: Abdominal aortic aneurysm Aortic dissection Aortic regurgitation Aortic stenosis Congenital (present ...

  4. Examination of a 15. 24-cm ball valve from the Morgantown Energy Technology Center Lock Hopper Valve Testing and Development Project: failure analysis report

    SciTech Connect

    Danyluk, S.; Diercks, D.; Dragel, G.M.

    1980-01-01

    A 15.24-cm ball valve failed while undergoing tests in simulated lock hopper service. The valve stem developed severe torsional deformation after 3134 cycles while handling limestone fines, and a replacement stem also exhibited deformation after an additional 124 cycles. The test was terminated at that point due to excessive valve leakage. Inspection of the valve at METC revealed large quantities of limestone fines packed between the valve ball and the body, and also revealed chipping of the chromium oxide coating around the valve stem slot. The valve seats, ball, and stem were sent to the Materials Science Division of Argonne National Laboratory for further examination. A visual examination at Argonne confirmed the general features seen at METC, and also revealed chipping of the coating on the overspray region of one of the valve seats. It was determined that the torque required to cause gross plastic deformation of the valve stem was well below that which the actuator was capable of applying in the valve test at METC. A microstructural examination of sections from each of the two valve seats indicated no significant debonding of the coating, and an independent analysis by the Linde Division of Union Carbide Corp. found the coating to meet the manufacturer's specifications. Variations in coating thickness on the valve ball of the order of 50% were observed using eddy-current techniques, but absolute values for the coating thicknesses were not obtained.Hardness readings on the valve-seat coating material were found to be slightly below the specified values, but the difference did not appear to be significant.

  5. Periodic cages.

    PubMed

    Diudea, Mircea V; Nagy, Csaba L; Silaghi-Dumitrescu, Ioan; Graovac, Ante; Janezic, Dusanka; Vikić-Topić, Drazen

    2005-01-01

    Various cages are constructed by using three types of caps: f-cap (derived from spherical fullerenes by deleting zones of various size), kf-cap (obtainable by cutting off the polar ring, of size k), and t-cap ("tubercule"-cap). Building ways are presented, some of them being possible isomerization routes in the real chemistry of fullerenes. Periodic cages with ((5,7)3) covering are modeled, and their constitutive typing enumeration is given. Spectral data revealed some electronic periodicity in fullerene clusters. Semiempirical and strain energy calculations complete their characterization. PMID:15807490

  6. Aortic insufficiency

    MedlinePlus

    ... Heart valve - aortic regurgitation; Valvular disease - aortic regurgitation; AI - aortic insufficiency ... BA. Valvular heart disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: ...

  7. Aortic Aneurysm

    MedlinePlus

    ... chest and abdomen. There are two types of aortic aneurysm: Thoracic aortic aneurysms - these occur in the part of the aorta running through the chest Abdominal aortic aneurysms - these occur in the part of the aorta ...

  8. Aortic Aneurysm

    MedlinePlus

    ... chest and abdomen. There are two types of aortic aneurysm: Thoracic aortic aneurysms (TAA) - these occur in the part of the aorta running through the chest Abdominal aortic aneurysms (AAA) - these occur in the part of the ...

  9. Aortic insufficiency

    MedlinePlus

    Aortic valve prolapse; Aortic regurgitation ... Any condition that prevents the aortic valve from closing completely can cause this problem. When the valve doesn't close all the way, a small amount of blood comes ...

  10. [A case of ruptured aneurysm in a patient over 90 years of age, successfully treated by clipping with the use of a one-way ball valve for cisternal drainage].

    PubMed

    Kubo, S; Nakata, H; Miyasyo, K; Yoshimine, T

    2000-10-01

    The authors report a case of ruptured aneurysm in a patient in her 90's who was treated by clipping and returned to her independent life after discharge. A 91-year-old woman with a diagnosis of SAH of Hunt & Kosnik Grade III was treated using a conventional clipping operation with cisternal drainage. The cisternal drainage was assembled as a closed system using a newly developed one-way ball valve to regulate the CSF outflow. With this system the patient was able to take any posture and do any movement she wished, not being obligned to stay in bed. Early postoperative rehabilitation was able to be started to prevent pneumonia and muscular atrophy. The drainage was stopped on the 27th postoperative day when the CSF became clear. During the period of drainage, neither valve obstruction nor meningitis was noted. This valve system allows patients under cisternal drainage to move freely. It would be useful, especially when dealing with the elderly, to prevent unwanted complications often caused by postoperative restraint imposed by confinement to bed. PMID:11070911

  11. Metal seated ball valves with carbide coatings

    SciTech Connect

    Manuel, R.; Yung, E.

    1994-12-31

    Valvtechnologies valves utilize Alloy Carbide HVOF Sprayed RAM{reg_sign} Hardcoatings such as Chrome Carbide and Tungsten Carbide Coatings. The coatings are applied using a Proprietary Gun combusting Hydrogen and Oxygen. The powders are heated and accelerated toward the valve component forming a tenaciously bonded coating. Each coating is chosen depending upon the environment the valve will operate in. These valves have solved many Petro-Chemical service life problems. Free from the temperature limits of elastomers, the only sealing materials are metal, the carbides and grafoils (carbons). Operating temperatures to 982 C (1,800 F) are typical limits; 649 C (1,200 F) is common. Lower temperatures are also common, even in the cryogenic range. Even though the coatings have low thermal expansion rates, RAM{reg_sign} Hardcoatings can expand and contract with the base material and still maintain a seal.

  12. Aortic Aneurysm Statistics

    MedlinePlus

    ... Blood Pressure Salt Cholesterol Million Hearts® WISEWOMAN Aortic Aneurysm Fact Sheet Recommend on Facebook Tweet Share Compartir ... cause of most deaths from aortic aneurysms. Aortic Aneurysm in the United States Aortic aneurysms were the ...

  13. Abdominal Aortic Aneurysm (AAA)

    MedlinePlus

    ... Resources Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis ... aortic aneurysm treated? What is an abdominal aortic aneurysm? The aorta, the largest artery in the body, ...

  14. Aortic stenting.

    PubMed

    Droc, Ionel; Calinescu, Francisca Blanca; Droc, Gabriela; Blaj, Catalin; Dammrau, Rolf

    2015-01-01

    The approach to aortic pathology is nowadays more and more endovascular at both thoracic and abdominal levels. Thoracic stenting has gained worldwide acceptance as first intention to treat pathologies of the descending thoracic aorta. Indications have been extended to aortic arch aneurysms and also to diseases of the ascending aorta. The current devices in use for thoracic endovascular repair (TEVAR) are Medtronic Valiant, Gore TAG, Cook Tx2 and Jotec. The choice of the endograft depends on the thoracic aortic pathology and the anatomical suitability. The technological evolution of the abdominal aortic endografts was very rapid, arriving now at the fourth generation. We report the results of 55 elective cases of endovascular abdominal aortic repair (EVAR) performed in two vascular surgical centers in Romania and Germany. The prostheses used were 16 E-vita Abdominal XT, 12 Excluder, eight Talent, seven PowerLink, three Endurant and nine custom-made, fenestrated or branched from Jotec. The mean follow-up was 18 months with CT-scan, duplex ultrasound and contrast-enhanced ultrasound. The mortality was 2%. EVAR tends to become the gold standard for abdominal aortic aneurysm repair. Technological development of the devices with lowest profile introduction systems will permit to extend the anatomical indications to new frontiers. PMID:26200430

  15. Aortic dissection.

    PubMed

    Nienaber, Christoph A; Clough, Rachel E; Sakalihasan, Natzi; Suzuki, Toru; Gibbs, Richard; Mussa, Firas; Jenkins, Michael T; Thompson, Matt M; Evangelista, Arturo; Yeh, James S M; Cheshire, Nicholas; Rosendahl, Ulrich; Pepper, John

    2016-01-01

    Aortic dissection is a life-threatening condition caused by a tear in the intimal layer of the aorta or bleeding within the aortic wall, resulting in the separation (dissection) of the layers of the aortic wall. Aortic dissection is most common in those 65-75 years of age, with an incidence of 35 cases per 100,000 people per year in this population. Other risk factors include hypertension, dyslipidaemia and genetic disorders that involve the connective tissue, such as Marfan syndrome. Swift diagnostic confirmation and adequate treatment are crucial in managing affected patients. Contemporary management is multidisciplinary and includes serial non-invasive imaging, biomarker testing and genetic risk profiling for aortopathy. The choice of approach for repairing or replacing the damaged region of the aorta depends on the severity and the location of the dissection and the risks of complication from surgery. Open surgical repair is most commonly used for dissections involving the ascending aorta and the aortic arch, whereas minimally invasive endovascular intervention is appropriate for descending aorta dissections that are complicated by rupture, malperfusion, ongoing pain, hypotension or imaging features of high risk. Recent advances in the understanding of the underlying pathophysiology of aortic dissection have led to more patients being considered at substantial risk of complications and, therefore, in need of endovascular intervention rather than only medical or surgical intervention. PMID:27440162

  16. New Ventilated Isolation Cage

    PubMed Central

    Cook, Reginald O.

    1968-01-01

    A multifunction lid has been developed for a commercially available transparent animal cage which permits feeding, watering, viewing, long-term holding, and local transport of laboratory rodents on experiment while isolating the surrounding environment. The cage is airtight except for its inlet and exhaust high-efficiency particulate air filters, and it is completely steam-sterilizable. Opening of the cage's feed and water ports causes an inrush of high velocity air which prevents back-migration of aerosols and permits feeding and watering while eliminating need for chemical vapor decontamination. Ventilation system design permits the holding in adjacent cages of animals infected with different organisms without danger of cross-contamination; leaves the animal room odor-free; reduces required bedding changes to twice a month or less, and provides investigators with capability to control precisely individual cage ventilation rates. Forty-eight cages can be conveniently placed on a standard NIH “shoebox” cage rack (60 inches wide × 28 inches deep × 74 inches high) fitted with a simple manifold exhaust system. The entire system is mobile, requiring only an electrical power outlet. Principal application of the caging system is in the area of preventing exposure of animal caretakers to pathogenic substances associated with the animal host, and in reducing handling of animals and their exposure to extraneous contamination. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 9 PMID:5659368

  17. Acute Aortic Syndromes and Thoracic Aortic Aneurysm

    PubMed Central

    Ramanath, Vijay S.; Oh, Jae K.; Sundt, Thoralf M.; Eagle, Kim A.

    2009-01-01

    Acute and chronic aortic diseases have been diagnosed and studied by physicians for centuries. Both the diagnosis and treatment of aortic diseases have been steadily improving over time, largely because of increased physician awareness and improvements in diagnostic modalities. This comprehensive review discusses the pathophysiology and risk factors, classification schemes, epidemiology, clinical presentations, diagnostic modalities, management options, and outcomes of various aortic conditions, including acute aortic dissection (and its variants intramural hematoma and penetrating aortic ulcers) and thoracic aortic aneurysms. Literature searches of the PubMed database were conducted using the following keywords: aortic dissection, intramural hematoma, aortic ulcer, and thoracic aortic aneurysm. Retrospective and prospective studies performed within the past 20 years were included in the review; however, most data are from the past 15 years. PMID:19411444

  18. Aortic Valve Disease

    MedlinePlus

    ... Disease Tricuspid Valve Disease Cardiac Rhythm Disturbances Thoracic Aortic Aneurysm Pediatric and Congenital Heart Disease Heart abnormalities that ... Disease Tricuspid Valve Disease Cardiac Rhythm Disturbances Thoracic Aortic Aneurysm Aortic Valve Disease Overview The human heart has ...

  19. Thoracic aortic aneurysm

    MedlinePlus

    Aortic aneurysm - thoracic; Syphilitic aneurysm; Aneurysm - thoracic aortic ... The most common cause of a thoracic aortic aneurysm is hardening of the ... with high cholesterol, long-term high blood pressure, or who ...

  20. Percutaneous Transcatheter Aortic Disc Valve Prosthesis Implantation: A Feasibility Study

    SciTech Connect

    Sochman, Jan

    2000-09-15

    Purpose: Over the past 30 years there have been experimental efforts at catheter-based management of aortic valve regurgitation with the idea of extending treatment to nonsurgical candidates. A new catheter-based aortic valve design is described.Methods: The new catheter-delivered valve consists of a stent-based valve cage with locking mechanism and a prosthetic flexible tilting valve disc. The valve cage is delivered first followed by deployment and locking of the disc. In acute experiments, valve implantation was done in four dogs.Results: Valve implantation was successful in all four animals. The implanted valve functioned well for the duration of the experiments (up to 3 hr).Conclusion: The study showed the implantation feasibility and short-term function of the tested catheter-based aortic disc valve. Further experimental studies are warranted.

  1. John Cage Discusses Fluxus.

    ERIC Educational Resources Information Center

    Snyder, Ellsworth

    1992-01-01

    Presents an informal discussion with composer John Cage which includes his response to George Maciunas' work, his recollections of Marcel Duchamp, the complex relationship between inelegant material and revealing works of art, neo-Dada and neo-Fluxus, Wittgenstein and the artist's ultimate responsibility to initiate a change in the viewer or…

  2. Aortic valve decalcification revisited.

    PubMed

    Marty, A T; Mufti, S; Murabit, I

    1989-11-01

    A 75-year-old woman with a small calcified aortic root, severe aortic stenosis and triple vessel coronary artery disease developed angina at rest. Aortic valve decalcification and quadruple aorto-coronary bypass were done as her aortic root was too small and calcified to do anything else. Postoperative clinical and hemodynamic results have been excellent. Literature review supports application of this therapy in selected patients with trileaflet senescent aortic stenosis. PMID:2614067

  3. Aortic valve replacement in rheumatoid aortic incompetence.

    PubMed Central

    Devlin, A B; Goldstraw, P; Caves, P K

    1978-01-01

    Rheumatoid aortic valve disease is uncommon. and there are few reports of valve replacement in this condition. Aortic valve replacement and partial pericardiectomy was performed in a patient with acute rheumatoid aortitis and aortic incompetence. Previous reports suggest that any patient with rheumatoid arthritis who develops cardiac symptoms should be carefully assessed for surgically treatable involvement of the pericardium or heart valves. Images PMID:725829

  4. Abdominal aortic aneurysm

    MedlinePlus

    ... to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes ... blood pressure Male gender Genetic factors An abdominal aortic aneurysm is most often seen in males over age ...

  5. Aortic aneurysm repair - endovascular

    MedlinePlus

    ... Endovascular aneurysm repair - aorta; AAA repair - endovascular; Repair - aortic aneurysm - endovascular ... leaking or bleeding. You may have an abdominal aortic aneurysm that is not causing any symptoms or problems. ...

  6. Aortic aneurysm repair - endovascular

    MedlinePlus

    EVAR; Endovascular aneurysm repair - aorta; AAA repair - endovascular; Repair - aortic aneurysm - endovascular ... leaking or bleeding. You may have an abdominal aortic aneurysm that is not causing any symptoms or problems. ...

  7. Abdominal Aortic Aneurysms: Treatments

    MedlinePlus

    ... information Membership Directory (SIR login) Interventional Radiology Abdominal Aortic Aneurysms Interventional Radiologists Treat Abdominal Aneurysms Nonsurgically Interventional radiologists ...

  8. Transcatheter aortic valve implantation

    PubMed Central

    Oliemy, Ahmed

    2014-01-01

    Transcatheter aortic valve implantation was developed to offer a therapeutic solution to patients with severe symptomatic aortic stenosis who are not candidates for conventional aortic valve replacement. The improvement in transcatheter aortic valve implantation outcomes is still of concern in the areas of stroke, vascular injury, heart block, paravalvular regurgitation and valve durability. Concomitantly, the progress, both technical and in terms of material advances of transcatheter valve systems, as well as in patient selection, renders transcatheter aortic valve implantation an increasingly viable treatment for more and more patients with structural heart disease. PMID:25374670

  9. The Cage-Busting Teacher

    ERIC Educational Resources Information Center

    Hess, Frederick M.

    2015-01-01

    "The Cage-Busting Teacher" adopts the logic of "Cage-Busting Leadership" and applies it to the unique challenges and opportunities of classroom teachers. Detailed, accessible, and thoroughly engaging, it uncovers the many ways in which teachers can break out of familiar constraints in order to influence school and classroom…

  10. Building a better Faraday cage

    NASA Astrophysics Data System (ADS)

    MartinAlfven; Wright, David; skocpol; Rounce, Graham; Richfield, Jon; W, Nick; wheelsonfire

    2015-11-01

    In reply to the physicsworld.com news article “Are Faraday cages less effective than previously thought?” (15 September, http://ow.ly/SfklO), about a study that indicated, based on mathematical modelling, that conducting wire-mesh cages may not be as good at excluding electromagnetic radiation as is commonly assumed.

  11. Aortic Valve Sparing in Different Aortic Valve and Aortic Root Conditions.

    PubMed

    David, Tirone E

    2016-08-01

    The development of aortic valve-sparing operations (reimplantation of the aortic valve and remodeling of the aortic root) expanded the surgical armamentarium for treating patients with aortic root dilation caused by a variety of disorders. Young adults with aortic root aneurysms associated with genetic syndromes are ideal candidates for reimplantation of the aortic valve, and the long-term results have been excellent. Incompetent bicuspid aortic valves with dilated aortic annuli are also satisfactorily treated with the same type of operation. Older patients with ascending aortic aneurysm and aortic insufficiency secondary to dilated sinotubular junction and a normal aortic annulus can be treated with remodeling of the aortic root or with reimplantation of the aortic valve. The first procedure is simpler, and both procedures are likely equally effective. As with any heart valve-preserving procedure, patient selection and surgical expertise are keys to successful and durable repairs. PMID:27491910

  12. Acute aortic syndrome

    PubMed Central

    2016-01-01

    Acute aortic syndrome (AAS) is a term used to describe a constellation of life-threatening aortic diseases that have similar presentation, but appear to have distinct demographic, clinical, pathological and survival characteristics. Many believe that the three major entities that comprise AAS: aortic dissection (AD), intramural hematoma (IMH) and penetrating aortic ulcer (PAU), make up a spectrum of aortic disease in which one entity may evolve into or coexist with another. Much of the confusion in accurately classifying an AAS is that they present with similar symptoms: typically acute onset of severe chest or back pain, and may have similar radiographic features, since the disease entities all involve injury or disruption of the medial layer of the aortic wall. The accurate diagnosis of an AAS is often made at operation. This manuscript will attempt to clarify the similarities and differences between AD, IMH and PAU of the ascending aorta and describe the challenges in distinguishing them from one another. PMID:27386405

  13. Acute aortic syndrome.

    PubMed

    Corvera, Joel S

    2016-05-01

    Acute aortic syndrome (AAS) is a term used to describe a constellation of life-threatening aortic diseases that have similar presentation, but appear to have distinct demographic, clinical, pathological and survival characteristics. Many believe that the three major entities that comprise AAS: aortic dissection (AD), intramural hematoma (IMH) and penetrating aortic ulcer (PAU), make up a spectrum of aortic disease in which one entity may evolve into or coexist with another. Much of the confusion in accurately classifying an AAS is that they present with similar symptoms: typically acute onset of severe chest or back pain, and may have similar radiographic features, since the disease entities all involve injury or disruption of the medial layer of the aortic wall. The accurate diagnosis of an AAS is often made at operation. This manuscript will attempt to clarify the similarities and differences between AD, IMH and PAU of the ascending aorta and describe the challenges in distinguishing them from one another. PMID:27386405

  14. Juxtarenal aortic occlusion.

    PubMed Central

    Tapper, S S; Jenkins, J M; Edwards, W H; Mulherin, J L; Martin, R S; Edwards, W H

    1992-01-01

    The authors' experience with 113 aortic occlusions in 103 patients during a 26-year period (1965 to 1991) is reviewed. The authors found three distinct patterns of presentation: group I (n = 26) presented with acute aortic occlusion, group II (n = 66) presented with chronic aortic occlusion, and group III (n = 21) presented with complete occlusion of an aortic graft. Perioperative mortality rates were 31%, 9%, and 4.7% for each respective group and achieved statistical significance when comparing group I with group II (p = 0.009) and group I with group III (p = 0.015). Group I presented with profound metabolic insults due to acute ischemia and fared poorly. Group II presented with chronic claudication and did well long-term. Group III presented with acute ischemia but did well because of established collateral circulation. The treatment and expected outcome of aortic occlusion depends on the cause. PMID:1616381

  15. Conservative Management of Chronic Aortic Dissection with Underlying Aortic Aneurysm

    PubMed Central

    Yusuf Beebeejaun, Mohammad; Malec, Aleksandra; Gupta, Ravi

    2013-01-01

    Aortic dissection is one of the most common aortic emergencies affecting around 2000 Americans each year. It usually presents in the acute state but in a small percentage of patients aortic dissections go unnoticed and these patients survive without any adequate therapy. With recent advances in medical care and diagnostic technologies, aortic dissection can be successfully managed through surgical or medical options, consequently increasing the related survival rate. However, little is known about the optimal long-term management of patients suffering from chronic aortic dissection. The purpose of the present report is to review aortic dissection, namely its pathology and the current diagnostic tools available, and to discuss the management options for chronic aortic dissection. We report a patient in which chronic aortic dissection presented with recurring episodes of vomiting and also discuss the management plan of our patient who had a chronic aortic dissection as well as an underlying aortic aneurysm. PMID:24179638

  16. Furnished Cage System and Hen Well-Being: Comparative Effects of Furnished Cages and Battery Cages on Behavioral Exhibitions in White Leghorn Chickens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The battery cage system is being banned in the European Union before or by 2012; and the furnished cage system will be the only cage system allowed after 2012. This study was conducted to examine the different effects of caging systems, furnished cages vs. battery cages, on bird behaviors. One hundr...

  17. Sutureless aortic valve replacement

    PubMed Central

    Phan, Kevin

    2015-01-01

    The increasing incidence of aortic stenosis and greater co-morbidities and risk profiles of the contemporary patient population has driven the development of minimally invasive aortic valve surgery and percutaneous transcatheter aortic valve implantation (TAVI) techniques to reduce surgical trauma. Recent technological developments have led to an alternative minimally invasive option which avoids the placement and tying of sutures, known as “sutureless” or rapid deployment aortic valves. Potential advantages for sutureless aortic prostheses include reducing cross-clamp and cardiopulmonary bypass (CPB) duration, facilitating minimally invasive surgery and complex cardiac interventions, whilst maintaining satisfactory hemodynamic outcomes and low paravalvular leak rates. However, given its recent developments, the majority of evidence regarding sutureless aortic valve replacement (SU-AVR) is limited to observational studies and there is a paucity of adequately-powered randomized studies. Recently, the International Valvular Surgery Study Group (IVSSG) has formulated to conduct the Sutureless Projects, set to be the largest international collaborative group to investigate this technology. This keynote lecture will overview the use, the potential advantages, the caveats, and current evidence of sutureless and rapid deployment aortic valve replacement (AVR). PMID:25870807

  18. Abdominal aortic aneurysm.

    PubMed

    Keisler, Brian; Carter, Chuck

    2015-04-15

    Abdominal aortic aneurysm refers to abdominal aortic dilation of 3.0 cm or greater. The main risk factors are age older than 65 years, male sex, and smoking history. Other risk factors include a family history of abdominal aortic aneurysm, coronary artery disease, hypertension, peripheral artery disease, and previous myocardial infarction. Diagnosis may be made by physical examination, an incidental finding on imaging, or ultrasonography. The U.S. Preventive Services Task Force released updated recommendations for abdominal aortic aneurysm screening in 2014. Men 65 to 75 years of age with a history of smoking should undergo one-time screening with ultrasonography based on evidence that screening will improve abdominal aortic aneurysm-related mortality in this population. Men in this age group without a history of smoking may benefit if they have other risk factors (e.g., family history of abdominal aortic aneurysm, other vascular aneurysms, coronary artery disease). There is inconclusive evidence to recommend screening for abdominal aortic aneurysm in women 65 to 75 years of age with a smoking history. Women without a smoking history should not undergo screening because the harms likely outweigh the benefits. Persons who have a stable abdominal aortic aneurysm should undergo regular surveillance or operative intervention depending on aneurysm size. Surgical intervention by open or endovascular repair is the primary option and is typically reserved for aneurysms 5.5 cm in diameter or greater. There are limited options for medical treatment beyond risk factor modification. Ruptured abdominal aortic aneurysm is a medical emergency presenting with hypotension, shooting abdominal or back pain, and a pulsatile abdominal mass. It is associated with high prehospitalization mortality. Emergent surgical intervention is indicated for a rupture but has a high operative mortality rate. PMID:25884861

  19. System for remotely servicing a top loading captive ball valve

    DOEpatents

    Berry, Stephen M.; Porter, Matthew L.

    1996-01-01

    An attachment for facilitating servicing of a valve, the valve including: an assembly composed of a valve seat defining a flow path, a flow control member movable relative to the valve seat for blocking or unblocking the valve seat, and a control device including a stem coupled to the flow control member and operable for moving the flow control member relative to the valve seat; a housing for receiving the assembly, the housing having an opening via which the assembly can be removed from, and installed in, the housing, and the housing having a plurality of threaded studs which surround the opening and project away from the housing; a valve housing cover for closing and sealing the opening in the housing, the cover having a first bore for passage of the stem of the control device when the assembly is installed in the housing and a plurality of second bores each located for passage of a respective stud when the cover closes the opening in the housing. A plurality of threaded nuts are engageable with the studs for securing the cover to the housing when the cover closes the opening in the housing, wherein the attachment comprises: a plurality of nut guide devices removable from the housing and each operatively associated with a respective stud for retaining a respective nut and guiding the respective nut into alignment with the respective stud to enable the respective nut to be rotated into engagement with the respective stud; and aligning the nut guide devices with the studs.

  20. System for remotely servicing a top loading captive ball valve

    DOEpatents

    Berry, S.M.; Porter, M.L.

    1996-06-25

    An attachment for facilitating servicing of a valve is disclosed including: an assembly composed of a valve seat defining a flow path, a flow control member movable relative to the valve seat for blocking or unblocking the valve seat, and a control device including a stem coupled to the flow control member and operable for moving the flow control member relative to the valve seat; a housing for receiving the assembly, the housing having an opening via which the assembly can be removed from, and installed in, the housing, and the housing having a plurality of threaded studs which surround the opening and project away from the housing; a valve housing cover for closing and sealing the opening in the housing, the cover having a first bore for passage of the stem of the control device when the assembly is installed in the housing and a plurality of second bores each located for passage of a respective stud when the cover closes the opening in the housing. A plurality of threaded nuts are engageable with the studs for securing the cover to the housing when the cover closes the opening in the housing, wherein the attachment comprises: a plurality of nut guide devices removable from the housing and each operatively associated with a respective stud for retaining a respective nut and guiding the respective nut into alignment with the respective stud to enable the respective nut to be rotated into engagement with the respective stud; and aligning the nut guide devices with the studs. 7 figs.

  1. An evaluation of intra-cage ventilation in three animal caging systems.

    PubMed

    Keller, L S; White, W J; Snider, M T; Lang, C M

    1989-05-01

    Although temperature and relative humidity have been quantitated and their effects on research data studied, few studies have measured the air turnover rates at cage level. We evaluated the air distribution and air turnover rates in unoccupied shoe-box mouse cages, filter-top covered cages and shoe-box mouse cages housed in a flexible film isolator by using discontinuous gas chromatography/mass spectrometry and smoke. Results showed that air turnover was most rapid in the unoccupied shoe-box mouse cage and slowest in the filter-top covered cage. Placing mice in the filter-top covered cage did not significantly improve the air turnover rate. Although filter-top covered cages reduce cage-to-cage transmission of disease, the poor airflow observed within these cages could lead to a buildup of gaseous pollutants that may adversely affect the animal's health. PMID:2724925

  2. Spectral moments of fullerene cages

    NASA Astrophysics Data System (ADS)

    Zhang, Hongxing; Balasubramanian, K.

    Based on the symmetric method, analytical expression or recursive relations for the spectral moments of the C20, C24, C26, C28, C30, C32, C36, C38, C40, C42, C44, C50 and C60 fullerene cage clusters are obtained by factoring the original graphs and the corresponding characteristic polynomials into their smaller subgraphs and subpolynomials. We also give numerical results for the spectral moments. It is demonstrated that the symmetric method is feasible in enumerating the moments as well as factoring the characteristic polynomials for fullerene cages.

  3. Harms titanium mesh cage fracture

    PubMed Central

    Klezl, Zdenek; Bookland, Markus J.; Wolinsky, Jean-Paul; Rezek, Zdenek; Gokaslan, Ziya L.

    2007-01-01

    Interbody fusion has become a mainstay of surgical management for lumbar fractures, tumors, spondylosis, spondylolisthesis and deformities. Over the years, it has undergone a number of metamorphoses, as novel instrumentation and approaches have arisen to reduce complications and enhance outcomes. Interbody fusion procedures are common and successful, complications are rare and most often do not involve the interbody device itself. We present here a patient who underwent an anterior L4 corpectomy with Harms cage placement and who later developed a fracture of the lumbar titanium mesh cage (TMC). This report details the presentation and management of this rare complication, as well as discusses the biomechanics underlying this rare instrumentation failure. PMID:17497187

  4. Microclimate in two types of rat cages.

    PubMed

    Hirsjärvi, P A; Väliaho, T U

    1987-04-01

    The microclimate in two types of rat cages (a Makrolon type IV with a solid floor and a stainless steel cage with a wire mesh floor (five rats per cage)) placed in the same macro-environment was compared. The temperature, relative humidity and ammonia concentration in the cages were measured twice a day for 8 days. The cages were cleaned every 4 days. The greatest difference between the cage types was in the ammonia build-up. In Makrolon cages the ammonia concentration never reached 5 ppm, whereas in steel cages it showed a constant increase and already exceeded the threshold limit for man (25 ppm for 8 h per day) on the third day after cleaning. PMID:3599880

  5. Aortic valve surgery - open

    MedlinePlus

    ... choose to have your aortic valve surgery at a center that does many of these procedures. ... DA, Harken AH. Acquired heart disease: valvular. In: Townsend CM, ... Textbook of Cardiovascular Medicine . 10th ed. Philadelphia, PA: ...

  6. Double aortic arch

    MedlinePlus

    ... double aortic arch may press on the windpipe (trachea) and esophagus, leading to trouble breathing and swallowing. ... to relieve pressure on the esophagus and windpipe (trachea). The surgeon ties off the smaller branch and ...

  7. [Acute aortic syndrome].

    PubMed

    Nienaber, Christoph A

    2016-06-01

    Acute aortic syndrome is the common denominator for acute events to the aortic wall and encompasses dissection of the aorta, intramural hematoma, formation of aortic ulcers and trauma to the aorta with an annual incidence of up to 35 cases/100.000 between 65 and 75 years of age. Both, inflammation and/or microtrauma at the level of the aortic media layer, and a genetic disposition are promoting elements of AAS, while the extent and anatomic involvement of the ascending aorta call for either surgical resection/repair in the proximal part of the aorta, or an endovascular solution for pathologies in the distal aorta; in all cases of dissection (regardless of location) reconstruction/realignment has been proven to portend better long-term outcomes (in addition to medical management of blood pressure). PMID:27254622

  8. Abdominal aortic aneurysm

    MedlinePlus

    ... main blood vessel that supplies blood to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs ... dissection). Symptoms of rupture include: Pain in the abdomen or back. The pain may be severe, sudden, ...

  9. DNA Cages with Icosahedral Symmetry in Bionanotechnology

    NASA Astrophysics Data System (ADS)

    Jonoska, Nataša; Taormina, Anne; Twarock, Reidun

    Blueprints for polyhedral cages with icosahedral symmetry made of circular DNA molecules are provided. The basic rule is that every edge of the cage is met twice in opposite directions by the DNA strand(s), and vertex junctions are realized by a set of admissible junction types. As nanocontainers for cargo storage and delivery, the icosidodecahedral cages are of special interest because they have the largest volume per surface ratio of all cages discussed here.

  10. Abdominal aortic aneurysm.

    PubMed

    Setacci, Francesco; Galzerano, Giuseppe; De Donato, Gianmarco; Benevento, Domenico; Guerrieri, Massimiliano W; Ruzzi, Umberto; Borrelli, Maria P; Setacci, Carlo

    2016-02-01

    Endovascular repair of abdominal aortic aneurysms has become a milestone in the treatment of patients with abdominal aortic aneurysm. Technological improvement allows treatment in more and more complex cases. This review summarizes all grafts available on the market. A complete review of most important trial on this topic is provided to the best of our knowledge, and technical tips and tricks for standard cases are also included. PMID:26771730

  11. Be a Cage-Buster

    ERIC Educational Resources Information Center

    Hess, Frederick M.

    2013-01-01

    "A cage-buster can't settle for ambiguity, banalities, or imprecision," writes well-known educator and author Rick Hess. "These things provide dark corners where all manners of ineptitude and excuse-making can hide." Hess suggests that leaders need to clearly define the problems they're trying to solve and open…

  12. A Mobile Phone Faraday Cage

    ERIC Educational Resources Information Center

    French, M. M. J.

    2011-01-01

    A Faraday cage is an interesting physical phenomenon where an electromagnetic wave can be excluded from a volume of space by enclosure with an electrically conducting material. The practical application of this in the classroom is to block the signal to a mobile phone by enclosing it in a metal can. The background of the physics behind this is…

  13. Surgical Aortic Valvuloplasty Versus Balloon Aortic Valve Dilatation in Children.

    PubMed

    Donald, Julia S; Konstantinov, Igor E

    2016-09-01

    Balloon aortic valve dilatation (BAD : is assumed to provide the same outcomes as surgical aortic valvuloplasty (SAV). However, the development of precise modern surgical valvuloplasty techniques may result in better long-term durability of the aortic valve repair. This review of the recent literature suggests that current SAV provides a safe and durable repair. Furthermore, primary SAV appears to have greater freedom from reintervention and aortic valve replacement when compared to BAD. PMID:27587493

  14. Aortic regurgitation after transcatheter aortic valve replacement.

    PubMed

    Werner, Nikos; Sinning, Jan-Malte

    2014-01-01

    Paravalvular aortic regurgitation (AR) negatively affects prognosis following transcatheter aortic valve replacement (TAVR). As transcatheter heart valves (THV) are anchored using a certain degree of oversizing at the level of the aortic annulus, incomplete stent frame expansion because of heavily annular calcifications, suboptimal placement of the prosthesis, and/or annulus-prosthesis size-mismatch can contribute to paravalvular AR with subsequent increased mortality risk. Echocardiography is essential to differentiate between transvalvular and paravalvular AR and to further elucidate the etiology of AR during the procedure. However, because echocardiographic quantification of AR in TAVR patients remains challenging, especially in the implantation situation, a multimodal approach to the evaluation of AR with use of hemodynamic measurements and imaging modalities is useful to precisely quantify the severity of AR immediately after valve deployment. "Next-generation" THVs are already on the market and first results show that paravalvular AR related to design modifications (eg, paravalvular space-fillers, full repositionability) are rarely seen in these valve types.  PMID:24632758

  15. The influence of cage positioning and cage type on cage migration and fusion rates in patients with monosegmental posterior lumbar interbody fusion and posterior fixation

    PubMed Central

    Abbushi, Alexander; Čabraja, Mario; Thomale, Ulrich-Wilhelm; Woiciechowsky, Christian

    2009-01-01

    In posterior lumbar interbody fusion, cage migrations and lower fusion rates compared to autologous bone graft used in the anterior lumbar interbody fusion procedure are documented. Anatomical and biomechanical data have shown that the cage positioning and cage type seem to play an important role. Therefore, the aim of the present study was to evaluate the impact of cage positioning and cage type on cage migration and fusion. We created a grid system for the endplates to analyze different cage positions. To analyze the influence of the cage type, we compared “closed” box titanium cages with “open” box titanium cages. This study included 40 patients with 80 implanted cages. After pedicle screw fixation, 23 patients were treated with a “closed box” cage and 17 patients with an “open box” cage. The follow-up period averaged 25 months. Twenty cages (25%) showed a migration into one vertebral endplate of <3 mm and four cages (5%) showed a migration of ≥3 mm. Cage migration was highest in the medio-medial position (84.6%), followed by the postero-lateral (42.9%), and the postero-medial (16%) cage position. Closed box cages had a significantly higher migration rate than open box cages, but fusion rates did not differ. In conclusion, cage positioning and cage type influence cage migration. The medio-medial cage position showed the highest migration rate. Regarding the cage type, open box cages seem to be associated with lower migration rates compared to closed box cages. However, the cage type did not influence bone fusion. PMID:19475436

  16. Aortic aneurysm repair - endovascular- discharge

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000236.htm Aortic aneurysm repair - endovascular - discharge To use the sharing features ... enable JavaScript. AAA repair - endovascular - discharge; Repair - aortic aneurysm - endovascular - discharge; EVAR - discharge; Endovascular aneurysm repair - discharge ...

  17. Screening for Abdominal Aortic Aneurysm

    MedlinePlus

    Understanding Task Force Recommendations Screening for Abdominal Aortic Aneurysm The U.S. Preventive Services Task Force (Task Force) ... final recommendation statement on Screening for Abdominal Aortic Aneurysm. This final recommendation statement applies to adults ages ...

  18. Aneurysms: thoracic aortic aneurysms.

    PubMed

    Chun, Kevin C; Lee, Eugene S

    2015-04-01

    Thoracic aortic aneurysms (TAAs) have many possible etiologies, including congenital heart defects (eg, bicuspid aortic valves, coarctation of the aorta), inherited connective tissue disorders (eg, Marfan, Ehlers-Danlos, Loeys-Dietz syndromes), and degenerative conditions (eg, medial necrosis, atherosclerosis of the aortic wall). Symptoms of rupture include a severe tearing pain in the chest, back, or neck, sometimes associated with cardiovascular collapse. Before rupture, TAAs may exert pressure on other thoracic structures, leading to a variety of symptoms. However, most TAAs are asymptomatic and are found incidentally during imaging for other conditions. Diagnosis is confirmed with computed tomography scan or echocardiography. Asymptomatic TAAs should be monitored with imaging at specified intervals and patients referred for repair if the TAAs are enlarging rapidly (greater than 0.5 cm in diameter over 6 months for heritable etiologies; greater than 0.5 cm over 1 year for degenerative etiologies) or reach a critical aortic diameter threshold for elective surgery (5.5 cm for TAAs due to degenerative etiologies, 5.0 cm when associated with inherited syndromes). Open surgery is used most often to treat asymptomatic TAAs in the ascending aorta and aortic arch. Asymptomatic TAAs in the descending aorta often are treated medically with aggressive blood pressure control, though recent data suggest that endovascular procedures may result in better long-term survival rates. PMID:25860136

  19. [Thoracoabdominal aortic aneurysm].

    PubMed

    Kalder, J; Kotelis, D; Jacobs, M J

    2016-09-01

    Thoracoabdominal aortic aneurysms (TAAA) are rare events with an incidence of 5.9 cases per 100,000 persons per year. In Germany approximately 940 TAAA procedures are performed annually. The cause of TAAA is mostly degenerative but they can also occur on the basis of an aortic dissection or connective tissue disease (e. g. Marfan's syndrome). Patients often have severe comorbidities and suffer from hypertension, coronary heart disease or chronic obstructive pulmonary disease, mostly as a result of smoking. Operative treatment is indicated when the maximum aortic diameter has reached 6 cm (> 5 cm in patients with connective tissue disease) or the aortic diameter rapidly increases (> 5 mm/year). Treatment options are open surgical aortic repair with extracorporeal circulation, endovascular repair with branched/fenestrated endografts and parallel grafts (chimneys) or a combination of open and endovascular procedures (hybrid procedures). Mortality rates after both open and endovascular procedures are approximately 8 % depending on the extent of the repair. Furthermore, there are relevant risks of complications, such as paraplegia (up to 20 %) and the necessity for dialysis. In recent years several approaches to minimize these risks have been proposed. Besides cardiopulmonary risk evaluation, clinical assessment of patients by the physician with respect to the patient-specific anatomy influences the allocation of patients to one treatment option or another. Surgery of TAAA should ideally be performed in high-volume centers in order to achieve better results. PMID:27558261

  20. Electronic cages for living cells.

    PubMed

    Al Saeed, Sarah; Bakewell, David J

    2015-08-01

    Design and construction of an electronic cage is described which enables real-time manipulation of live and dead eukaryotic cells. Non-uniform, radio frequency (RF) AC electric fields are used to enable translational and rotational movement of cells, known as dielectrophoresis (DEP) and electro-rotation (EROT), and distinguish their state as viable and non-viable. A concentric multilayered mathematical model, applicable for eukaryotic cells, is also developed, coded and implemented. The simulations predict three dielectric dispersions in the DEP and EROT spectra, though in practice the third is very small so that two are observed. The cage is part of a multi-staged project incorporating controller and DEP/EROT digital signal generator and image processing. PMID:26736401

  1. Transcatheter Aortic Valve Implantation.

    PubMed

    Malaisrie, S Chris; Iddriss, Adam; Flaherty, James D; Churyla, Andrei

    2016-05-01

    Severe aortic stenosis (AS) is a life-threatening condition when left untreated. Aortic valve replacement (AVR) is the gold standard treatment for the majority of patients; however, transcatheter aortic valve implantation/replacement (TAVI/TAVR) has emerged as the preferred treatment for high-risk or inoperable patients. The concept of transcatheter heart valves originated in the 1960s and has evolved into the current Edwards Sapien and Medtronic CoreValve platforms available for clinical use. Complications following TAVI, including cerebrovascular events, perivalvular regurgitation, vascular injury, and heart block have decreased with experience and evolving technology, such that ongoing trials studying TAVI in lower risk patients have become tenable. The multidisciplinary team involving the cardiac surgeon and cardiologist plays an essential role in patient selection, procedural conduct, and perioperative care. PMID:27021619

  2. Abdominal Aortic Aneurysms

    PubMed Central

    Fortner, George; Johansen, Kaj

    1984-01-01

    Aneurysms are common in our increasingly elderly population, and are a major threat to life and limb. Until the advent of vascular reconstructive techniques, aneurysm patients were subject to an overwhelming risk of death from exsanguination. The first successful repair of an abdominal aortic aneurysm using an interposed arterial homograft was reported by Dubost in 1952. A milestone in the evolution of vascular surgery, this event and subsequent diagnostic, operative and prosthetic graft refinements have permitted patients with an unruptured abdominal aortic aneurysm to enjoy a better prognosis than patients with almost any other form of major systemic illness. Images PMID:6702193

  3. Polymers containing borane or carborane cage compounds and related applications

    DOEpatents

    Bowen, III, Daniel E; Eastwood, Eric A

    2013-04-23

    Polymers comprising residues of cage compound monomers having at least one polyalkoxy silyl substituent are provided. The cage compound monomers are selected from borane cage compound monomers comprising at least 7 cage atoms and/or carborane cage compound monomers comprising 7 to 11 cage compound monomers. Such polymers can further comprise one or more reactive matrices and/or co-monomers covalently bound with the cage compound monomer residues. Articles of manufacture comprising such polymers are also disclosed.

  4. Cleaning Animals' Cages With Little Water

    NASA Technical Reports Server (NTRS)

    Harman, Benjamin J.

    1989-01-01

    Proposed freeze/thaw method for cleaning animals' cages requires little extra weight and consumes little power and water. Cleaning concept developed for maintaining experimental rat cages on extended space missions. Adaptable as well to similar use on Earth. Reduces cleaning time. Makes use of already available facilities such as refrigerator, glove box, and autoclave. Rat waste adheres to steel-wire-mesh floor of cage. Feces removed by loosening action of freezing-and-thawing process, followed by blast of air.

  5. Segmental Aortic Stiffening Contributes to Experimental Abdominal Aortic Aneurysm Development

    PubMed Central

    Raaz, Uwe; Zöllner, Alexander M.; Schellinger, Isabel N.; Toh, Ryuji; Nakagami, Futoshi; Brandt, Moritz; Emrich, Fabian C.; Kayama, Yosuke; Eken, Suzanne; Adam, Matti; Maegdefessel, Lars; Hertel, Thomas; Deng, Alicia; Jagger, Ann; Buerke, Michael; Dalman, Ronald L.; Spin, Joshua M.; Kuhl, Ellen; Tsao, Philip S.

    2015-01-01

    Background Stiffening of the aortic wall is a phenomenon consistently observed in age and in abdominal aortic aneurysm (AAA). However, its role in AAA pathophysiology is largely undefined. Methods and Results Using an established murine elastase-induced AAA model, we demonstrate that segmental aortic stiffening (SAS) precedes aneurysm growth. Finite element analysis (FEA) reveals that early stiffening of the aneurysm-prone aortic segment leads to axial (longitudinal) wall stress generated by cyclic (systolic) tethering of adjacent, more compliant wall segments. Interventional stiffening of AAA-adjacent aortic segments (via external application of surgical adhesive) significantly reduces aneurysm growth. These changes correlate with reduced segmental stiffness of the AAA-prone aorta (due to equalized stiffness in adjacent segments), reduced axial wall stress, decreased production of reactive oxygen species (ROS), attenuated elastin breakdown, and decreased expression of inflammatory cytokines and macrophage infiltration, as well as attenuated apoptosis within the aortic wall. Cyclic pressurization of segmentally stiffened aortic segments ex vivo increases the expression of genes related to inflammation and extracellular matrix (ECM) remodeling. Finally, human ultrasound studies reveal that aging, a significant AAA risk factor, is accompanied by segmental infrarenal aortic stiffening. Conclusions The present study introduces the novel concept of segmental aortic stiffening (SAS) as an early pathomechanism generating aortic wall stress and triggering aneurysmal growth, thereby delineating potential underlying molecular mechanisms and therapeutic targets. In addition, monitoring SAS may aid the identification of patients at risk for AAA. PMID:25904646

  6. Bicuspid aortic valve

    MedlinePlus

    ... is unclear, but it is the most common congenital heart disease . It often runs in families. The bicuspid aortic ... A.M. Editorial team. Related MedlinePlus Health Topics Congenital Heart Defects Heart Valve Diseases Browse the Encyclopedia A.D.A.M., Inc. ...

  7. Aortic valve annuloplasty: new single suture technique.

    PubMed

    Schöllhorn, Joachim; Rylski, Bartosz; Beyersdorf, Friedhelm

    2014-06-01

    Reconstruction strategies for aortic valve insufficiency in the presence of aortic annulus dilatation are usually surgically challenging. We demonstrate a simple, modified Taylor technique of downsizing and stabilization of the aortic annulus using a single internal base suture. Since April 2011, 22 consecutive patients have undergone safe aortic valve annuloplasty. No reoperations for aortic valve insufficiency and no deaths occurred. PMID:24882316

  8. Trp-Cage Folding on Organic Surfaces.

    PubMed

    Levine, Zachary A; Fischer, Sean A; Shea, Joan-Emma; Pfaendtner, Jim

    2015-08-20

    Trp-cage is an artificial miniprotein that is small, stable, and fast folding due to concerted hydrophobic shielding of a Trp residue by polyproline helices. Simulations have extensively characterized Trp-cage; however, the interactions of Trp-cage with organic surfaces (e.g., membranes) and their effect on protein conformation are largely unknown. To better understand these interactions we utilized a combination of replica-exchange molecular dynamics (REMD) and metadynamics (MetaD), to investigate Trp-cage folding on self-assembled monolayers (SAMs). We found that, with REMD and MetaD, Trp-cage strongly binds to neutral CH3 surfaces (-25kT) and moderately adsorbs to anionic COOH interfaces (-7.6kT), with hydrophobic interactions driving CH3 adhesion and electrostatic attractions driving COOH adhesion. Similar to solid-state surfaces, SAMs facilitate a number of intermediate Trp-cage conformations between folded and unfolded states. Regarding Trp-cage's aromatic groups in neutral CH3 systems, Tyr becomes oriented parallel to the surface in order to maximize hydrophobic interactions while Trp remains caged perpendicular to the surface; however, Trp can reorient itself parallel to the interface as the miniprotein more closely binds to the surface. In contrast, Tyr and Trp are both repelled from COOH surfaces, though the Trp-cage still adheres to the anionic interface via Lys and its N-terminated Asn residue. PMID:26207727

  9. Humidity and Cage and Bedding Temperatures in Unoccupied Static Mouse Caging after Steam Sterilization

    PubMed Central

    Ward, Gina M; Cole, Kelly; Faerber, Jennifer; Hankenson, F Claire

    2009-01-01

    Contemporary rodent caging and equipment often are sterilized by steam autoclaves prior to use in facilities. This work assessed the microenvironment of unoccupied static mouse cages after steam sterilization to determine when internal temperatures had cooled to levels appropriate for rodent housing. Polycarbonate static cages containing food and corncob bedding were stacked (10 rows × 7 columns) in duplicate (front and back; n = 140 cages) on a storage truck and autoclaved to 249 °F (121 °C). Cages (n = 6) were assessed to represent top, middle, and bottom rows and edges of columns. After cage sterilization, hygrothermometers were placed in cages to measure internal cage temperature (IT), bedding temperature (BT), and cage humidity (CH) every 10 min for 150 min. At time 0, there were no significant differences in averaged temperatures or humidity across cage locations: IT, 95.9 °F; BT, 109.8 °F; and CH, 84.1%. Over time, significant positional effects occurred. Whereas IT and BT for cages in the center row cooled more slowly than those on the bottom row, CH in top row cages decreased more quickly compared with other cages. After 150 min, the average measures overall were IT, 75.8 °F; BT, 77.9 °F; and CH, 82.4%. Comparison of the overall measures at 150 min with those of cages cooled overnight (IT, 72.4 °F; BT, 71.0 °F; and CH, 49%) and cages housing mice (IT, 72.2 °F; BT, 70.7 °F; and CH, 82%) indicated that a poststerilization cooling period of greater than 2.5 h was necessary to achieve permissible rodent housing conditions at our institution, particularly with corncob bedding autoclaved within the cage. PMID:19930826

  10. Recent advances in aortic valve disease: highlights from a bicuspid aortic valve to transcatheter aortic valve replacement.

    PubMed

    Augoustides, John G T; Wolfe, Yanika; Walsh, Elizabeth K; Szeto, Wilson Y

    2009-08-01

    There have been major advances in the management of aortic valve disease. Because bicuspid aortic valve is common and predicts an increased risk of adverse aortic events, these patients merit aortic surveillance and consideration for ascending aortic replacement when its diameter exceeds 4.0 cm. Serial quantitative echocardiographic analysis, as compared with traditional clinical markers, can result in better timing of surgical intervention for aortic regurgitation. Furthermore, echocardiographic analysis of aortic regurgitation can classify the mechanism based on cusp mobility to guide aortic valve repair. In aortic root replacement, aortic valve preservation with reimplantation is a mainstream surgical option in Marfan syndrome to offer freedom from valve-related anticoagulation. Prosthetic aortic root replacement has further alternatives with the introduction of the aortic neosinus design and acceptable clinical outcomes with the porcine xenograft. Because aortic valve prosthesis-patient mismatch (PPM) may adversely affect patient outcome, its perioperative prevention is important. Furthermore, significant functional mitral regurgitation in association with aortic stenosis often resolves after aortic valve replacement. Echocardiographic assessment of the aortic valve must include valve area because the transaortic pressure gradient may be low in severe stenosis. Aortic valve replacement with partial sternotomy is safe and offers a reasonable less invasive alternative. Transcatheter aortic valve replacement, whether transfemoral or transapical, has revolutionized aortic valve replacement; it remains a major theme in the specialty for 2009 and beyond. PMID:19497768

  11. First direct aortic retrievable transcatheter aortic valve implantation in humans.

    PubMed

    Chandrasekhar, Jaya; Glover, Chris; Labinaz, Marino; Ruel, Marc

    2014-11-01

    We describe 2 cases in which transcatheter aortic valve implantation was performed with a Portico prosthesis (St Jude Medical, St Paul, MN) through a direct aortic approach. In 1 of the cases, prosthesis retrieval was needed during the procedure and was essential to the successful outcome. This is the first report, to our knowledge, of direct aortic Portico prosthesis implantation, and it highlights the significance of the retrievable nature of this device. PMID:25442452

  12. Transcatheter ACURATE-TA Aortic Valve Implantation in a Patient With a Previous Mechanical Mitral Valve.

    PubMed

    Bagur, Rodrigo; Kiaii, Bob; Teefy, Patrick J; Diamantouros, Pantelis; Harle, Christopher; Goela, Aashish; Chan, Ian; Chu, Michael W A

    2015-11-01

    Transcatheter aortic valve implantation (TAVI) in the presence of a mechanical mitral valve (MMV) prosthesis is still challenging because of the rigid mitral frame within the aortomitral curtain. Moreover, low-lying coronary ostia represent a hazardous problem of coronary obstruction, especially in narrow or porcelain aortic roots. The present case demonstrates the successful management of 2 challenging anatomical issues, the rigid cage of the MMV and the low-lying left main coronary ostium (LMCO), with the implantation of the ACURATE-TA bioprosthesis (Symetis SA, Ecublens, Switzerland). It also highlights the importance of having multiple TAVI devices in order to choose the ideal transcatheter aortic bioprosthesis to fit the unique anatomical presentation of the patient. PMID:26522576

  13. [Stent Grafting for Aortic Dissection].

    PubMed

    Uchida, Naomichi

    2016-07-01

    The purpose of stent graft for aortic dissection is to terminate antegrade blood flow into the false lumen through primary entry. Early intervention for primary entry makes excellent aortic remodeling and emergent stent grafting for complicated acute type B aortic dissection is supported as a class I. On the other hand stent grafting for chronic aortic dissection is controversial. Early stent grafting is considered with in 6 months after on-set if the diameter of the descending aorta is more than 40 mm. Additional interventions for residual false lumen on the downstream aorta are still required. Stent graft for re-entry, candy-plug technique, and double stenting, other effective re-interventions were reported. Best treatment on the basis of each anatomical and physical characteristics should be selected in each institution. Frozen elephant trunk is alternative procedure for aortic dissection without the need to take account of proximal anatomical limitation and effective for acute type A aortic dissection. PMID:27440026

  14. COATING ALTERNATIVES GUIDE (CAGE) USER'S GUIDE

    EPA Science Inventory

    The guide provides instructions for using the Coating Alternatives GuidE (CAGE) software program, version 1.0. It assumes that the user is familiar with the fundamentals of operating an IBM-compatible personal computer (PC) under the Microsoft disk operating system (MS-DOS). CAGE...

  15. High-temperature bearing-cage materials

    NASA Technical Reports Server (NTRS)

    Anderson, W. J.; Zaretsky, E. V.

    1968-01-01

    Evaluation tests conducted at temperatures of 500 and 700 degrees F reveal that S-Monel and AISI M-1 steel are suitable as high temperature cage materials for precision bearings. The area of the wear scar in the cage pocket that developed during the test was used as the measure of wear.

  16. 50 CFR 648.75 - Cage identification.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... are issued, or if rendered null and void in accordance with 15 CFR part 904. (d) Return. Tags that... Clam and Ocean Quahog Fisheries § 648.75 Cage identification. Except as provided in § 648.76, the... clams and ocean quahogs: (a) Tagging. Before offloading, all cages that contain surfclams or...

  17. Geomechanics of fracture caging in wellbores

    NASA Astrophysics Data System (ADS)

    Weijermars, Ruud; Zhang, Xi; Schultz-Ela, Dan

    2013-06-01

    This study highlights the occurrence of so-called `fracture cages' around underbalanced wellbores, where fractures cannot propagate outwards due to unfavourable principal stress orientations. The existence of such cages is demonstrated here by independent analytical and numerical methods. We explain the fracture caging mechanism and pinpoint the physical parameters and conditions for its control. This new insight has great practical relevance for the effectiveness and safety of drilling operations in general, and hydraulic fracturing in particular. Fracture caging runaway poses a hazard for drilling operations in overpressured formations. Recognition of the fracture caging mechanism also opens up new opportunities for controlled engineering of its effects by the manipulation of the Frac number in wells in order to bring more precision in the fracking process of tight formations.

  18. Aortic dimensions in Turner syndrome.

    PubMed

    Quezada, Emilio; Lapidus, Jodi; Shaughnessy, Robin; Chen, Zunqiu; Silberbach, Michael

    2015-11-01

    In Turner syndrome, linear growth is less than the general population. Consequently, to assess stature in Turner syndrome, condition-specific comparators have been employed. Similar reference curves for cardiac structures in Turner syndrome are currently unavailable. Accurate assessment of the aorta is particularly critical in Turner syndrome because aortic dissection and rupture occur more frequently than in the general population. Furthermore, comparisons to references calculated from the taller general population with the shorter Turner syndrome population can lead to over-estimation of aortic size causing stigmatization, medicalization, and potentially over-treatment. We used echocardiography to measure aortic diameters at eight levels of the thoracic aorta in 481 healthy girls and women with Turner syndrome who ranged in age from two to seventy years. Univariate and multivariate linear regression analyses were performed to assess the influence of karyotype, age, body mass index, bicuspid aortic valve, blood pressure, history of renal disease, thyroid disease, or growth hormone therapy. Because only bicuspid aortic valve was found to independently affect aortic size, subjects with bicuspid aortic valve were excluded from the analysis. Regression equations for aortic diameters were calculated and Z-scores corresponding to 1, 2, and 3 standard deviations from the mean were plotted against body surface area. The information presented here will allow clinicians and other caregivers to calculate aortic Z-scores using a Turner-based reference population. © 2015 Wiley Periodicals, Inc. PMID:26118429

  19. Micromanaging abdominal aortic aneurysms.

    PubMed

    Maegdefessel, Lars; Spin, Joshua M; Adam, Matti; Raaz, Uwe; Toh, Ryuji; Nakagami, Futoshi; Tsao, Philip S

    2013-01-01

    The contribution of abdominal aortic aneurysm (AAA) disease to human morbidity and mortality has increased in the aging, industrialized world. In response, extraordinary efforts have been launched to determine the molecular and pathophysiological characteristics of the diseased aorta. This work aims to develop novel diagnostic and therapeutic strategies to limit AAA expansion and, ultimately, rupture. Contributions from multiple research groups have uncovered a complex transcriptional and post-transcriptional regulatory milieu, which is believed to be essential for maintaining aortic vascular homeostasis. Recently, novel small noncoding RNAs, called microRNAs, have been identified as important transcriptional and post-transcriptional inhibitors of gene expression. MicroRNAs are thought to "fine tune" the translational output of their target messenger RNAs (mRNAs) by promoting mRNA degradation or inhibiting translation. With the discovery that microRNAs act as powerful regulators in the context of a wide variety of diseases, it is only logical that microRNAs be thoroughly explored as potential therapeutic entities. This current review summarizes interesting findings regarding the intriguing roles and benefits of microRNA expression modulation during AAA initiation and propagation. These studies utilize disease-relevant murine models, as well as human tissue from patients undergoing surgical aortic aneurysm repair. Furthermore, we critically examine future therapeutic strategies with regard to their clinical and translational feasibility. PMID:23852016

  20. Holographic photolysis of caged neurotransmitters

    PubMed Central

    Lutz, Christoph; Otis, Thomas S.; DeSars, Vincent; Charpak, Serge; DiGregorio, David A.; Emiliani, Valentina

    2009-01-01

    Stimulation of light-sensitive chemical probes has become a powerful tool for the study of dynamic signaling processes in living tissue. Classically, this approach has been constrained by limitations of lens–based and point-scanning illumination systems. Here we describe a novel microscope configuration that incorporates a nematic liquid crystal spatial light modulator (LC-SLM) to generate holographic patterns of illumination. This microscope can produce illumination spots of variable size and number and patterns shaped to precisely match user-defined elements in a specimen. Using holographic illumination to photolyse caged glutamate in brain slices, we demonstrate that shaped excitation on segments of neuronal dendrites and simultaneous, multi-spot excitation of different dendrites enables precise spatial and rapid temporal control of glutamate receptor activation. By allowing the excitation volume shape to be tailored precisely, the holographic microscope provides an extremely flexible method for activation of various photosensitive proteins and small molecules. PMID:19160517

  1. Transcatheter aortic valve implantation.

    PubMed

    Nielsen, Hans Henrik Møller

    2012-12-01

    Transcatheter aortic valve implantation (TAVI) was introduced experimentally in 1989, based on a newly developed heart valve prosthesis - the stentvalve. The valve was invented by a Danish cardiologist named Henning Rud Andersen. The new valve was revolutionary. It was foldable and could be inserted via a catheter through an artery in the groin, without the need for heart lung machine. This allowed for a new valve implantation technique, much less invasive than conventional surgical aortic valve replacement (SAVR). Surgical aortic valve replacement is safe and improves symptoms along with survival. However, up to 1/3 of patients with aortic valve stenosis cannot complete the procedure due to frailty. The catheter technique was hoped to provide a new treatment option for these patients. The first human case was in 2002, but more widespread clinical use did not begin until 2006-2010. Today, in 2011, more than 40,000 valves have been implanted worldwide. Initially, because of the experimental character of the procedure, TAVI was reserved for patients who could not undergo SAVR due to high risk. The results in this group of patients were promising. The procedural safety was acceptable, and the patients experienced significant improvements in their symptoms. Three of the papers in this PhD-thesis are based on the outcome of TAVI at Skejby Hospital, in this high-risk population [I, II and IV]. Along with other international publications, they support TAVI as being superior to standard medical treatment, despite a high risk of prosthetic regurgitation. These results only apply to high-risk patients, who cannot undergo SAVR. The main purpose of this PhD study has been to investigate the quality of TAVI compared to SAVR, in order to define the indications for this new procedure. The article attached [V] describes a prospective clinical randomised controlled trial, between TAVI to SAVR in surgically amenable patients over 75 years of age with isolated aortic valve stenosis

  2. Quadricuspid Aortic Valve: A Rare Congenital Cause of Aortic Insufficiency

    PubMed Central

    Vasudev, Rahul; Shah, Priyank; Bikkina, Mahesh; Shamoon, Fayez

    2016-01-01

    Quadricuspid aortic valve (QAV) is a rare congenital cardiac anomaly causing aortic regurgitation usually in the fifth to sixth decade of life. Earlier, the diagnosis was mostly during postmortem or intraoperative, but now with the advent of better imaging techniques such as transthoracic echocardiography, transesophageal echocardiography (TEE), and cardiac magnetic resonance imaging, more cases are being diagnosed in asymptomatic patients. We present a case of a 39-year-old male who was found to have QAV, with the help of TEE, while undergoing evaluation for a diastolic murmur. The patient was found to have Type B QAV with moderate aortic regurgitation. We also present a brief review of classification, pathophysiology, and embryological basis of this rare congenital anomaly. The importance of diagnosing QAV lies in the fact that majority of these patients will require surgery for aortic regurgitation and close follow-up so that aortic valve replacement/repair is done before the left ventricular decompensation occurs. PMID:27195176

  3. Management of Acute Aortic Syndrome and Chronic Aortic Dissection

    SciTech Connect

    Nordon, Ian M. Hinchliffe, Robert J.; Loftus, Ian M.; Morgan, Robert A.; Thompson, Matt M.

    2011-10-15

    Acute aortic syndrome (AAS) describes several life-threatening aortic pathologies. These include intramural hematoma, penetrating aortic ulcer, and acute aortic dissection (AAD). Advances in both imaging and endovascular treatment have led to an increase in diagnosis and improved management of these often catastrophic pathologies. Patients, who were previously consigned to medical management or high-risk open surgical repair, can now be offered minimally invasive solutions with reduced morbidity and mortality. Information from the International Registry of Acute Aortic Dissection (IRAD) database demonstrates how in selected patients with complicated AAD the 30-day mortality from open surgery is 17% and endovascular stenting is 6%. Despite these improvements in perioperative deaths, the risks of stroke and paraplegia remain with endovascular treatment (combined outcome risk 4%). The pathophysiology of each aspect of AAS is described. The best imaging techniques and the evolving role of endovascular techniques in the definitive management of AAS are discussed incorporating strategies to reduce perioperative morbidity.

  4. Active cage model of glassy dynamics.

    PubMed

    Fodor, Étienne; Hayakawa, Hisao; Visco, Paolo; van Wijland, Frédéric

    2016-07-01

    We build up a phenomenological picture in terms of the effective dynamics of a tracer confined in a cage experiencing random hops to capture some characteristics of glassy systems. This minimal description exhibits scale invariance properties for the small-displacement distribution that echo experimental observations. We predict the existence of exponential tails as a crossover between two Gaussian regimes. Moreover, we demonstrate that the onset of glassy behavior is controlled only by two dimensionless numbers: the number of hops occurring during the relaxation of the particle within a local cage and the ratio of the hopping length to the cage size. PMID:27575182

  5. Thoracic aortic aneurysms and pregnancy.

    PubMed

    Coulon, Capucine

    2015-11-01

    Half of acute aortic dissection in women under the age of 40 occurs during pregnancy or peripartum period. Marfan syndrome is the most common syndromic presentation of ascending aortic aneurysm, but other syndromes such as vascular Ehlers-Danlos syndrome, Loeys-Dietz syndrome and Turner syndrome also have ascending aortic aneurysms and the associated cardiovascular risk of aortic dissection and rupture. Management of aortic root aneurysm has been established in recent recommendations, even if levels of evidence are weak. Pregnancy and postpartum period should be followed very closely and determined to be at high risk. Guidelines suggest that women with aortopathy should be counseled against the risk of pregnancy and about the heritable nature of the disease prior to pregnancy. PMID:26454306

  6. Intraoperative aortic dissection

    PubMed Central

    Singh, Ajmer; Mehta, Yatin

    2015-01-01

    Intraoperative aortic dissection is a rare but fatal complication of open heart surgery. By recognizing the population at risk and by using a gentle operative technique in such patients, the surgeon can usually avoid iatrogenic injury to the aorta. Intraoperative transesophageal echocardiography and epiaortic scanning are invaluable for prompt diagnosis and determination of the extent of the injury. Prevention lies in the strict control of blood pressure during cannulation/decannulation, construction of proximal anastomosis, or in avoiding manipulation of the aorta in high-risk patients. Immediate repair using interposition graft or Dacron patch graft is warranted to reduce the high mortality associated with this complication. PMID:26440240

  7. 30 CFR 56.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Closing cage doors or gates. 56.19070 Section... Hoisting Hoisting Procedures § 56.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  8. 30 CFR 56.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Closing cage doors or gates. 56.19070 Section... Hoisting Hoisting Procedures § 56.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  9. 30 CFR 57.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Closing cage doors or gates. 57.19070 Section... Hoisting Hoisting Procedures § 57.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  10. 30 CFR 57.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Closing cage doors or gates. 57.19070 Section... Hoisting Hoisting Procedures § 57.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  11. 30 CFR 56.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Closing cage doors or gates. 56.19070 Section... Hoisting Hoisting Procedures § 56.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  12. 30 CFR 57.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Closing cage doors or gates. 57.19070 Section... Hoisting Hoisting Procedures § 57.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  13. 30 CFR 57.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Closing cage doors or gates. 57.19070 Section... Hoisting Hoisting Procedures § 57.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  14. 30 CFR 57.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Closing cage doors or gates. 57.19070 Section... Hoisting Hoisting Procedures § 57.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  15. 30 CFR 56.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Closing cage doors or gates. 56.19070 Section... Hoisting Hoisting Procedures § 56.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  16. 30 CFR 56.19070 - Closing cage doors or gates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Closing cage doors or gates. 56.19070 Section... Hoisting Hoisting Procedures § 56.19070 Closing cage doors or gates. Cage doors or gates shall be closed while persons are being hoisted; they shall not be opened until the cage has come to a stop....

  17. Compositions containing borane or carborane cage compounds and related applications

    SciTech Connect

    Bowen, III, Daniel E; Eastwood, Eric A

    2014-11-11

    Compositions comprising a polymer-containing matrix and a filler comprising a cage compound selected from borane cage compounds, carborane cage compounds, metal complexes thereof, residues thereof, mixtures thereof, and/or agglomerations thereof, where the cage compound is not covalently bound to the matrix polymer. Methods of making and applications for using such compositions are also disclosed.

  18. Compositions containing borane or carborane cage compounds and related applications

    SciTech Connect

    Bowen, III, Daniel E.; Eastwood, Eric A.

    2015-09-15

    Compositions comprising a polymer-containing matrix and a filler comprising a cage compound selected from borane cage compounds, carborane cage compounds, metal complexes thereof, residues thereof, mixtures thereof, and/or agglomerations thereof, where the cage compound is not covalently bound to the matrix polymer. Methods of making and applications for using such compositions are also disclosed.

  19. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Maintenance of the CAGE... Maintenance of the CAGE file. (a) DLIS will accept written requests for changes to CAGE files, other than name...) Submit requests for changes to CAGE files on DD Form 2051, or electronic equivalent, to—Defense...

  20. Compositions containing borane or carborane cage compounds and related applications

    DOEpatents

    Bowen, III, Daniel E; Eastwood, Eric A

    2013-05-28

    Compositions comprising a polymer-containing matrix and a filler comprising a cage compound selected from borane cage compounds, carborane cage compounds, metal complexes thereof, residues thereof, mixtures thereof, and/or agglomerations thereof, where the cage compound is not covalently bound to the matrix polymer. Methods of making and applications for using such compositions are also disclosed.

  1. Dual-purpose laboratory cage/antenna

    NASA Technical Reports Server (NTRS)

    Lalande, B. H.

    1977-01-01

    Part of steel cage enclosing laboratory animals is used as an antenna to transmit biotelemetry over short distances. Receiving and signal processing equipment are located above ground potential to avoid transmission-path difficulties.

  2. Maintenance of a Drosophila melanogaster Population Cage

    PubMed Central

    Caravaca, Juan Manuel; Lei, Elissa P.

    2016-01-01

    Large quantities of DNA, RNA, proteins and other cellular components are often required for biochemistry and molecular biology experiments. The short life cycle of Drosophila enables collection of large quantities of material from embryos, larvae, pupae and adult flies, in a synchronized way, at a low economic cost. A major strategy for propagating large numbers of flies is the use of a fly population cage. This useful and common tool in the Drososphila community is an efficient way to regularly produce milligrams to tens of grams of embryos, depending on uniformity of developmental stage desired. While a population cage can be time consuming to set up, maintaining a cage over months takes much less time and enables rapid collection of biological material in a short period. This paper describes a detailed and flexible protocol for the maintenance of a Drosophila melanogaster population cage, starting with 1.5 g of harvested material from the previous cycle. PMID:27023790

  3. 50 CFR 648.77 - Cage identification.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... fishing year for which they are issued, or if rendered null and void in accordance with 15 CFR part 904... Atlantic Surf Clam and Ocean Quahog Fisheries § 648.77 Cage identification. Except as provided in §...

  4. 50 CFR 648.77 - Cage identification.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... fishing year for which they are issued, or if rendered null and void in accordance with 15 CFR part 904... Atlantic Surf Clam and Ocean Quahog Fisheries § 648.77 Cage identification. Except as provided in §...

  5. 50 CFR 648.77 - Cage identification.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... fishing year for which they are issued, or if rendered null and void in accordance with 15 CFR part 904... Atlantic Surf Clam and Ocean Quahog Fisheries § 648.77 Cage identification. Except as provided in §...

  6. CT of acute abdominal aortic disorders.

    PubMed

    Bhalla, Sanjeev; Menias, Christine O; Heiken, Jay P

    2003-11-01

    Aortic aneurysm rupture, aortic dissection, PAU, acute aortic occlusion, traumatic aortic injury, and aortic fistula represent acute abdominal aortic conditions. Because of its speed and proximity to the emergency department, helical CT is the imaging test of choice for these conditions. MR imaging also plays an important role in the imaging of aortic dissection and PAU, particularly when the patient is unable to receive intravenous contrast material. In this era of MDCT, conventional angiography is used as a secondary diagnostic tool to clarify equivocal findings on cross-sectional imaging. Ultrasound is helpful when CT is not readily available and the patient is unable or too unstable to undergo MR imaging. PMID:14661663

  7. Cage Change Intervals for Opossums (Monodelphis domestica) in Individually Ventilated Cages

    PubMed Central

    Allison, Sarah O; Criley, Jennifer M; Kim, Ji Young; Goodly, Lyndon J

    2011-01-01

    The opossum Monodelphis domestica is the most commonly used marsupial in biomedical research. At our institution, these opossums are housed in polycarbonate (35.6 cm × 25.4 cm × 17.8 cm) individually ventilated cages. Previous studies of the cage microenvironment of rodents housed in individually ventilated cages have demonstrated that the cage-change frequency could be extended from 7 to 14 d, without detriment to the animals’ wellbeing. We sought to determine whether the cage change frequency for opossums housed in individually ventilated cages could be extended to 14 d. Opossums were placed into 3 experimental groups: singly housed males, singly housed females, and females housed with litters. The 14-d testing period was repeated twice, with temperature, relative humidity, and ammonia levels tested on days 0, 7, and 14. Acceptable ranges for the cage microenvironment were based on standards followed by our institution for housing rodents: temperature between 22 to 26 °C, relative humidity between 30% to 70%, and ammonia less than 25 ppm. Throughout both 14-d testing periods, temperature, relative humidity, and ammonia levels for singly housed male and singly housed female opossums were within acceptable ranges. However, ammonia levels exceeded the recommended 25 ppm on day 7 of both testing periods for female opossums housed with litters. In summary, the cage-change frequency for a singly housed opossum in an individually ventilated cage can be extended to 14 d. PMID:22330710

  8. Aortic biomechanics in hypertrophic cardiomyopathy

    PubMed Central

    Badran, Hala Mahfouz; Soltan, Ghada; Faheem, Nagla; Elnoamany, Mohamed Fahmy; Tawfik, Mohamed; Yacoub, Magdi

    2015-01-01

    Background: Ventricular-vascular coupling is an important phenomenon in many cardiovascular diseases. The association between aortic mechanical dysfunction and left ventricular (LV) dysfunction is well characterized in many disease entities, but no data are available on how these changes are related in hypertrophic cardiomyopathy (HCM). Aim of the work: This study examined whether HCM alone is associated with an impaired aortic mechanical function in patients without cardiovascular risk factors and the relation of these changes, if any, to LV deformation and cardiac phenotype. Methods: 141 patients with HCM were recruited and compared to 66 age- and sex-matched healthy subjects as control group. Pulse pressure, aortic strain, stiffness and distensibility were calculated from the aortic diameters measured by M-mode echocardiography and blood pressure obtained by sphygmomanometer. Aortic wall systolic and diastolic velocities were measured using pulsed wave Doppler tissue imaging (DTI). Cardiac assessment included geometric parameters and myocardial deformation (strain and strain rate) and mechanical dyssynchrony. Results: The pulsatile change in the aortic diameter, distensibility and aortic wall systolic velocity (AWS') were significantly decreased and aortic stiffness index was increased in HCM compared to control (P < .001) In HCM AWS' was inversely correlated to age(r = − .32, P < .0001), MWT (r = − .22, P < .008), LVMI (r = − .20, P < .02), E/Ea (r = − .16, P < .03) LVOT gradient (r = − 19, P < .02) and severity of mitral regurg (r = − .18, P < .03) but not to the concealed LV deformation abnormalities or mechanical dyssynchrony. On multivariate analysis, the key determinant of aortic stiffness was LV mass index and LVOT obstruction while the role LV dysfunction in aortic stiffness is not evident in this population. Conclusion: HCM is associated with abnormal aortic mechanical properties. The severity of cardiac

  9. Self-Assembled Pyridine-Dipyrrolate Cages.

    PubMed

    Zhang, Huacheng; Lee, Juhoon; Lammer, Aaron D; Chi, Xiaodong; Brewster, James T; Lynch, Vincent M; Li, Hao; Zhang, Zhan; Sessler, Jonathan L

    2016-04-01

    An inherently nonlinear pyridine dipyrrolate ligand, namely 2,6-bis(3,4-diethyl-5-carboxy-1H-pyrrol-2yl)pyridine (compound 1), is able to distinguish between different zinc(II) cation sources, namely Zn(acac)2 and Zn(OAc)2, respectively. This differentiation is manifest both in terms of the observed fluorescent behavior in mixed organic media and the reaction chemistry. Treatment of 1 with Zn(acac)2 gives rise to a cage dimer, cage-1, wherein two molecules of compound 1 act as double bridging units to connect two individual cage subunits. As inferred from X-ray crystallographic studies, this cage system consists of discrete zinc dimers with hydroxide bridges that, with the assistance of bound DMF solvent molecules, serve to fix the geometry and orientation of the pyridine dipyrrolate building blocks. When a different zinc source, Zn(OAc)2, is used to carry out an ostensibly similar complexation reaction with compound 1, an acetate-bridged 1D abacus-like cage polymer is obtained as inferred from X-ray diffraction analysis. This extended solid state structure, cage-2, contains individual zinc dimer cage submits and appears stabilized by solvent molecules (DMF) and the counteranion (acetate). Rod-like assemblies are also observed by DLS and SEM. This construct, in contrast to cage-1, proved fluorescent in mixed organic media. The structure of the ligand itself (i.e., in the absence of Zn(II)) was confirmed by X-ray crystallographic analysis and was found to assemble into a supramolecular polymer. Conversion to a dimer form was seen upon the addition of TBAOAc. On the basis of the metric parameters, the structures seen in the solid state are stabilized via hydrogen bonding interactions involving solvent molecules. PMID:26972781

  10. Kinetically Trapped Tetrahedral Cages via Alkyne Metathesis.

    PubMed

    Lee, Semin; Yang, Anna; Moneypenny, Timothy P; Moore, Jeffrey S

    2016-02-24

    In dynamic covalent synthesis, kinetic traps are perceived as disadvantageous, hindering the system from reaching its thermodynamic equilibrium. Here we present the near-quantitative preparation of tetrahedral cages from simple tritopic precursors using alkyne metathesis. While the cages are the presumed thermodynamic sink, we experimentally demonstrate that the products no longer exchange their vertices once they have formed. The example reported here illustrates that kinetically trapped products may facilitate high yields of complex products from dynamic covalent synthesis. PMID:26854552

  11. Unusual Case of Overt Aortic Dissection Mimicking Aortic Intramural Hematoma

    PubMed Central

    Disha, Kushtrim; Kuntze, Thomas; Girdauskas, Evaldas

    2016-01-01

    We report an interesting case in which overt aortic dissection mimicked two episodes of aortic intramural hematoma (IMH) (Stanford A, DeBakey I). This took place over the course of four days and had a major influence on the surgical treatment strategy. The first episode of IMH regressed completely within 15 hours after it was clinically diagnosed and verified using imaging techniques. The recurrence of IMH was detected three days thereafter, resulting in an urgent surgical intervention. Overt aortic dissection with evidence of an intimal tear was diagnosed intraoperatively. PMID:27066437

  12. Minimally invasive aortic valve surgery.

    PubMed

    Castrovinci, Sebastiano; Emmanuel, Sam; Moscarelli, Marco; Murana, Giacomo; Caccamo, Giuseppa; Bertolino, Emanuela Clara; Nasso, Giuseppe; Speziale, Giuseppe; Fattouch, Khalil

    2016-09-01

    Aortic valve disease is a prevalent disorder that affects approximately 2% of the general adult population. Surgical aortic valve replacement is the gold standard treatment for symptomatic patients. This treatment has demonstrably proven to be both safe and effective. Over the last few decades, in an attempt to reduce surgical trauma, different minimally invasive approaches for aortic valve replacement have been developed and are now being increasingly utilized. A narrative review of the literature was carried out to describe the surgical techniques for minimally invasive aortic valve surgery and report the results from different experienced centers. Minimally invasive aortic valve replacement is associated with low perioperative morbidity, mortality and a low conversion rate to full sternotomy. Long-term survival appears to be at least comparable to that reported for conventional full sternotomy. Minimally invasive aortic valve surgery, either with a partial upper sternotomy or a right anterior minithoracotomy provides early- and long-term benefits. Given these benefits, it may be considered the standard of care for isolated aortic valve disease. PMID:27582764

  13. Minimally invasive aortic valve surgery

    PubMed Central

    Castrovinci, Sebastiano; Emmanuel, Sam; Moscarelli, Marco; Murana, Giacomo; Caccamo, Giuseppa; Bertolino, Emanuela Clara; Nasso, Giuseppe; Speziale, Giuseppe; Fattouch, Khalil

    2016-01-01

    Aortic valve disease is a prevalent disorder that affects approximately 2% of the general adult population. Surgical aortic valve replacement is the gold standard treatment for symptomatic patients. This treatment has demonstrably proven to be both safe and effective. Over the last few decades, in an attempt to reduce surgical trauma, different minimally invasive approaches for aortic valve replacement have been developed and are now being increasingly utilized. A narrative review of the literature was carried out to describe the surgical techniques for minimally invasive aortic valve surgery and report the results from different experienced centers. Minimally invasive aortic valve replacement is associated with low perioperative morbidity, mortality and a low conversion rate to full sternotomy. Long-term survival appears to be at least comparable to that reported for conventional full sternotomy. Minimally invasive aortic valve surgery, either with a partial upper sternotomy or a right anterior minithoracotomy provides early- and long-term benefits. Given these benefits, it may be considered the standard of care for isolated aortic valve disease. PMID:27582764

  14. Reoperative Aortic Root Replacement in Patients with Previous Aortic Root or Aortic Valve Procedures

    PubMed Central

    Chong, Byung Kwon; Jung, Sung-Ho; Choo, Suk Jung; Chung, Cheol Hyun; Lee, Jae Won; Kim, Joon Bum

    2016-01-01

    Background Generalization of standardized surgical techniques to treat aortic valve (AV) and aortic root diseases has benefited large numbers of patients. As a consequence of the proliferation of patients receiving aortic root surgeries, surgeons are more frequently challenged by reoperative aortic root procedures. The aim of this study was to evaluate the outcomes of redo-aortic root replacement (ARR). Methods We retrospectively reviewed 66 patients (36 male; mean age, 44.5±9.5 years) who underwent redo-ARR following AV or aortic root procedures between April 1995 and June 2015. Results Emergency surgeries comprised 43.9% (n=29). Indications for the redo-ARR were aneurysm (n=12), pseudoaneurysm (n=1), or dissection (n=6) of the residual native aortic sinus in 19 patients (28.8%), native AV dysfunction in 8 patients (12.1%), structural dysfunction of an implanted bioprosthetic AV in 19 patients (28.8%), and infection of previously replaced AV or proximal aortic grafts in 30 patients (45.5%). There were 3 early deaths (4.5%). During follow-up (median, 54.65 months; quartile 1–3, 17.93 to 95.71 months), there were 14 late deaths (21.2%), and 9 valve-related complications including reoperation of the aortic root in 1 patient, infective endocarditis in 3 patients, and hemorrhagic events in 5 patients. Overall survival and event-free survival rates at 5 years were 81.5%±5.1% and 76.4%±5.4%, respectively. Conclusion Despite technical challenges and a high rate of emergency conditions in patients requiring redo-ARR, early and late outcomes were acceptable in these patients. PMID:27525233

  15. Aortic dissection--an update.

    PubMed

    Mukherjee, Debabrata; Eagle, Kim A

    2005-06-01

    Acute aortic dissection is a medical emergency with high morbidity and mortality requiring emergent diagnosis and therapy. Rapid advances in noninvasive imaging technology have facilitated the early diagnosis of this condition and should be considered in the differential diagnosis of any patient with chest, back, or abdominal pain. Emergent surgery is the treatment for patients with type A dissection while optimal medical therapy is appropriate in patients with uncomplicated type B dissection. Adequate beta-blockade is the cornerstone of medical therapy. Patients who survive acute aortic dissection need long-term medical therapy with beta-blockers and statins and appropriate serial imaging follow-up. Future advances in this field include biomarkers in the early diagnosis of acute aortic dissection and presymptomatic diagnosis with genetic screening. Overall patients with aortic dissection are at high risk for an adverse outcome and need to be managed aggressively in hospital and long term with frequent follow-up. PMID:15973249

  16. Temperature dependence of polyhedral cage volumes in clathrate hydrates

    USGS Publications Warehouse

    Chakoumakos, B.C.; Rawn, C.J.; Rondinone, A.J.; Stern, L.A.; Circone, S.; Kirby, S.H.; Ishii, Y.; Jones, C.Y.; Toby, B.H.

    2003-01-01

    The polyhedral cage volumes of structure I (sI) (carbon dioxide, methane, trimethylene oxide) and structure II (sII) (methane-ethane, propane, tetrahydrofuran, trimethylene oxide) hydrates are computed from atomic positions determined from neutron powder-diffraction data. The ideal structural formulas for sI and sII are, respectively, S2L6 ?? 46H2O and S16L???8 ?? 136H2O, where S denotes a polyhedral cage with 20 vertices, L a 24-cage, and L??? a 28-cage. The space-filling polyhedral cages are defined by the oxygen atoms of the hydrogen-bonded network of water molecules. Collectively, the mean cage volume ratio is 1.91 : 1.43 : 1 for the 28-cage : 24-cage : 20-cage, which correspond to equivalent sphere radii of 4.18, 3.79, and 3.37 A??, respectively. At 100 K, mean polyhedral volumes are 303.8, 227.8, and 158.8 A??3 for the 28-cage, 24-cage, and 20-cage, respectively. In general, the 20-cage volume for a sII is larger than that of a sI, although trimethylene oxide is an exception. The temperature dependence of the cage volumes reveals differences between apparently similar cages with similar occupants. In the case of trimethylene oxide hydrate, which forms both sI and sII, the 20-cages common to both structures contract quite differently. From 220 K, the sII 20-cage exhibits a smooth monotonic reduction in size, whereas the sI 20-cage initially expands upon cooling to 160 K, then contracts more rapidly to 10 K, and overall the sI 20-cage is larger than the sII 20-cage. The volumes of the large cages in both structures contract monotonically with decreasing temperature. These differences reflect reoriented motion of the trimethyelene oxide molecule in the 24-cage of sI, consistent with previous spectroscopic and calorimetric studies. For the 20-cages in methane hydrate (sI) and a mixed methane-ethane hydrate (sII), both containing methane as the guest molecule, the temperature dependence of the 20-cage volume in sII is much less than that in sI, but sII is overall

  17. Uranium pyrophosphate / methylenediphosphonate polyoxometalate cage clusters

    SciTech Connect

    Ling, Jie; Qiu, Jie; Sigmon, Ginger E.; Ward, Matt; Szymanowski, Jennifer E.S.; Burns, Peter C

    2010-09-29

    Despite potential applications in advanced nuclear energy systems, nanoscale control of uranium materials is in its infancy. In its hexavalent state, U occurs as (UO{sub 2}){sup 2+} uranyl ions that are coordinated by various ligands to give square, pentagonal, or hexagonal bipyramids. Creation and design of nanostructured uranyl materials requires interruption of the tendency of uranyl bipyramids to share equatorial edges to form infinite sheets that occur in extended structures. Where a bidentate peroxide group bridges uranyl bipyramids, the configuration is inherently bent, fostering formation of cage clusters. Here the bent configurations of four- and five-membered rings of uranyl peroxide hexagonal bipyramids are bridged by pyrophosphate or methylenediphosphonate, creating eight chemically complex cage clusters with specific topologies. Chemical complexity in such clusters provides opportunities for the tuning of cage sizes, pore sizes, and properties such as aqueous solubility. Several of these are topological derivatives of simpler clusters that contain only uranyl bipyramids, whereas others exhibit new topologies.

  18. Hybrid Lanthanide-Actinide Peroxide Cage Clusters.

    PubMed

    Sigmon, Ginger E; Szymanowski, Jennifer E S; Carter, Korey P; Cahill, Christopher L; Burns, Peter C

    2016-03-21

    A cage cluster consisting of 31 uranyl and 9 Sm(3+) polyhedra self-assembles in an alkaline aqueous peroxide solution and crystallizes (U31Sm9). Trimers of Sm(3+) polyhedra are templated by μ3-η(2):η(2):η(2)-peroxide groups and link to oxo atoms of uranyl ions. Three such trimers link into a ring through uranyl hexagonal bipyramids, and these are attached through six polyhedra to a unit consisting of 21 uranyl hexagonal bipyramids to complete the cage. Luminescence spectra collected with an excitation wavelength of 420 nm reveal fine structure, which is not observed for a cluster containing only uranyl polyhedra. PMID:26923457

  19. Phosphonate Based High Nuclearity Magnetic Cages.

    PubMed

    Sheikh, Javeed Ahmad; Jena, Himanshu Sekhar; Clearfield, Abraham; Konar, Sanjit

    2016-06-21

    Transition metal based high nuclearity molecular magnetic cages are a very important class of compounds owing to their potential applications in fabricating new generation molecular magnets such as single molecular magnets, magnetic refrigerants, etc. Most of the reported polynuclear cages contain carboxylates or alkoxides as ligands. However, the binding ability of phosphonates with transition metal ions is stronger than the carboxylates or alkoxides. The presence of three oxygen donor sites enables phosphonates to bridge up to nine metal centers simultaneously. But very few phosphonate based transition metal cages were reported in the literature until recently, mainly because of synthetic difficulties, propensity to result in layered compounds, and also their poor crystalline properties. Accordingly, various synthetic strategies have been followed by several groups in order to overcome such synthetic difficulties. These strategies mainly include use of small preformed metal precursors, proper choice of coligands along with the phosphonate ligands, and use of sterically hindered bulky phosphonate ligands. Currently, the phosphonate system offers a library of high nuclearity transition metal and mixed metal (3d-4f) cages with aesthetically pleasing structures and interesting magnetic properties. This Account is in the form of a research landscape on our efforts to synthesize and characterize new types of phosphonate based high nuclearity paramagnetic transition metal cages. We quite often experienced synthetic difficulties with such versatile systems in assembling high nuclearity metal cages. Few methods have been emphasized for the self-assembly of phosphonate systems with suitable transition metal ions in achieving high nuclearity. We highlighted our journey from 2005 until today for phosphonate based high nuclearity transition metal cages with V(IV/V), Mn(II/III), Fe(III), Co(II), Ni(II), and Cu(II) metal ions and their magnetic properties. We observed that

  20. Bicontinuous Nanoporous Frameworks: Caged Longevity for Enzymes.

    PubMed

    Bae, Jae-Sung; Jeon, Eunkyung; Moon, Su-Young; Oh, Wangsuk; Han, Sun-Young; Lee, Jeong Hun; Yang, Sung Yun; Kim, Dong-Myung; Park, Ji-Woong

    2016-09-12

    The preparation of bicontinuous nanoporous covalent frameworks, which are promising for caging active enzymes, is demonstrated. The frameworks have three- dimensionally continuous, hydrophilic pores with widths varying between 5 and 30 nm. Enzymes were infiltrated into the bicontinuous pore by applying a pressured enzyme solution. The new materials and methods allowed the amount of caged proteins to be controlled precisely. The resulting enzyme-loaded framework films could be recycled many times with nearly no loss of catalytic activity. Entropic trapping of proteins by a bicontinuous pore with the right size distribution is an unprecedented strategy toward facile in vitro utilization of biocatalysts. PMID:27513827

  1. Coronary Flow Impacts Aortic Leaflet Mechanics and Aortic Sinus Hemodynamics

    PubMed Central

    Moore, Brandon L.; Dasi, Lakshmi Prasad

    2016-01-01

    Mechanical stresses on aortic valve leaflets are well-known mediators for initiating processes leading to calcific aortic valve disease. Given that non-coronary leaflets calcify first, it may be hypothesized that coronary flow originating from the ostia significantly influences aortic leaflet mechanics and sinus hemodynamics. High resolution time-resolved particle image velocimetry (PIV) measurements were conducted to map the spatiotemporal characteristics of aortic sinus blood flow and leaflet motion with and without physiological coronary flow in a well-controlled in vitro setup. The in vitro setup consists of a porcine aortic valve mounted in a physiological aorta sinus chamber with dynamically controlled coronary resistance to emulate physiological coronary flow. Results were analyzed using qualitative streak plots illustrating the spatiotemporal complexity of blood flow patterns, and quantitative velocity vector and shear stress contour plots to show differences in the mechanical environments between the coronary and non-coronary sinuses. It is shown that the presence of coronary flow pulls the classical sinus vorticity deeper into the sinus and increases flow velocity near the leaflet base. This creates a beneficial increase in shear stress and washout near the leaflet that is not seen in the non-coronary sinus. Further, leaflet opens approximately 10% farther into the sinus with coronary flow case indicating superior valve opening area. The presence of coronary flow significantly improves leaflet mechanics and sinus hemodynamics in a manner that would reduce low wall shear stress conditions while improving washout at the base of the leaflet. PMID:25636598

  2. [Aortic intramural hematoma. An atypical pattern equivalent to aortic dissection].

    PubMed

    López-Mínguez, J R; Merchán, A; Arrobas, J; Fernández, G; González-Egüaras, M; García-Andoaín, J M; Alonso, M; Gamero, C; Poblador, M A; Alonso, F

    1995-09-01

    A case is presented of a hypertensive woman who had suffered a stabbing back pain for some three hours, with mild irradiation to precordium and accompanied by vegetative signs. A sinusal rhythm and negative T waves of little depth were seen on the ECG. A transthoracic bidimensional echocardiogram (TTE) showed a normal left ventricle with a somewhat dilated aortic root and the existence of a double echo running parallel to the anterior wall of the aorta but non-ondulating and without a visible intimal flap. Because of suspected aortic dissection an urgent contrasted CAT and a transesophageal echocardiogram were performed. These were informed as an aneurysm of the aortic root with mural thrombus from the ascending to descending aorta, but with no existing intimal flap suggesting dissection. A cardiac catheterization showed a mildly some dilated aortic root without dissection signs and normal left ventricle and coronary arteries. The patient was presented for surgical evaluation but, since no dissection was present, was not considered urgent surgery; she was admitted to the coronary unit and died 48 hours later in a situation of acute pericardial tamponade, documented by TTE, surely due to rupture of the aortic root to pericardial sack. This way of presenting threatened aorta rupture that has been only recently recognized is discussed, as well as some misconceptions which must be avoided. PMID:7569267

  3. Abdominal aortic aneurysm repair - open - discharge

    MedlinePlus

    AAA - open - discharge; Repair - aortic aneurysm - open - discharge ... You had open aortic aneurysm surgery to repair an aneurysm (a widened part) in your aorta, the large artery that carries blood to your ...

  4. Cage RACK ventilation options for laboratory animal facilities.

    PubMed

    Stakutis, Richard E

    2003-09-01

    Individually ventilated cage systems have become the method of choice for housing rodents. The author describes the various options for cage ventilation, from using supply and exhaust fans to directly connecting the racks to the building ventilation system. PMID:12966448

  5. Design and modeling of Faraday cages for substrate noise isolation

    NASA Astrophysics Data System (ADS)

    Wu, Joyce H.; del Alamo, Jesús A.

    2013-07-01

    A Faraday cage structure using through-substrate vias is an effective strategy to suppress substrate crosstalk, particularly at high frequencies. Faraday cages can reduce substrate noise by 32 dB at 10 GHz, and 26 dB at 50 GHz. We have developed lumped-element, equivalent circuit models of the Faraday cages and test structures to better understand the performance of the Faraday cages. These models compare well to measured results and show that the vias of the Faraday cage act as an RLC shunt to ground that draws substrate current. Designing a Faraday cage to achieve optimum isolation requires low via impedance and mitigation of via sidewall capacitance. The Faraday cage inductance is correlated to the number of vias and via spacing of the cage and can be optimized for the frequency of operation.

  6. CO chemisorption on the surfaces of the golden cages

    SciTech Connect

    Huang, Wei; Bulusu, Satya; Pal, R; Zeng, Xiao Cheng; Wang, Lai S

    2009-12-18

    We report a joint experimental and theoretical study of CO chemisorption on the golden cages. We find that the Au17- cage is highly robust and retains its cage structure in Au17-CO-. On the other hand, the Au16 - cage is transformed to a structure similar to Au17- upon the adsorption of CO. Au18 - is known to consist of two nearly degenerate structures, i.e., a cage and a pyramidal isomer, which coexist in the cluster beam. However, upon CO chemisorption only the cage isomer is observed while the pyramidal isomer no longer exists due to its less favorable interaction with CO, compared to the cage isomer. We find that inclusion of the spin-orbit effects is critical in yielding simulated spectra in quantitative agreement with the experimental data and providing unequivocal structural information and molecular insights into the chemical interactions between CO and the golden cages.

  7. Chemical contamination of animal feeding systems: evaluation of two caging systems and standard cage-washing equipment.

    PubMed

    Fox, J G; Helfrich-Smith, M E

    1980-12-01

    Sodium fluorescein was added as a tracer to an ager gel diet which was fed for 5 day to 90 of 180 rats housed in two different polycarbonate caging systems, shoe-box cages and suspension solid-bottom cages. Cage racks, supplementary equipment, and case washer surfaces were analysed for fluorescein both before and after a complete wash and rinse cycle. Efficacy of washing was greater than 99% for both the inside and outside of the suspended cages and greater than 99% for the inside, but only 93% for the outside, of the shoe-box cages. The shoe-box cages, which were larger than the suspended cages, were spaced closer together on the washer rack, which may account for this variation in cleaning effectiveness. The cage washer surfaces and the water, which was recirculated during each cycle, also became contaminated with fluorescein. Strict adherence to proper cage-washing procedures and careful selection of cage design are important factors in controlling the potential for residual contamination of caging and cage-washing equipment. PMID:7464031

  8. Aortic or Mitral Valve Replacement With the Biocor and Biocor Supra

    ClinicalTrials.gov

    2016-03-09

    Aortic Valve Insufficiency; Aortic Valve Regurgitation; Aortic Valve Stenosis; Aortic Valve Incompetence; Mitral Valve Insufficiency; Mitral Valve Regurgitation; Mitral Valve Stenosis; Mitral Valve Incompetence

  9. Ascending Aortic Slide for Interrupted Aortic Arch Repair.

    PubMed

    Urencio, Miguel; Dodge-Khatami, Ali; Greenleaf, Chris E; Aru, Giorgio; Salazar, Jorge D

    2016-09-01

    For repair of interrupted aortic arch, unfavorable anatomy challenges a tension-free anastomosis. We describe a useful alternative surgical technique used in five neonates/infants, involving splitting the ascending aorta from the sinotubular junction to the arch origin, leftward and posterior "sliding" of the flap with anastomosis to the distal arch creating a native tissue bridge, and reconstruction with a patch. With wide interruption gaps between proximal and distal aortic portions, the ascending aortic slide is a safe and reproducible technique, providing a tension-free native tissue bridge with potential for growth, and a scaffold for patch augmentation in biventricular hearts, or for Norwood stage I in univentricular palliation. PMID:27587504

  10. Current aortic endografts for the treatment of abdominal aortic aneurysms.

    PubMed

    Colvard, Benjamin; Georg, Yannick; Chakfe, Nabil; Swanstrom, Lee

    2016-05-01

    Endovascular Aneurysm Repair is a widely adopted method of treatment for patients with abdominal aortic aneurysms. The minimally invasive approach offered with EVAR has become popular not only among physicians and patients, but in the medical device industry as well. Over the past 25 years the global market for aortic endografts has increased rapidly, resulting in a wide range of devices from various companies. Currently, there are seven endografts approved by the FDA for the treatment of abdominal aortic aneurysms. These devices offer a wide range of designs intended to increase inclusion criteria while decreasing technical complications such as endoleak and migration. Despite advances in device design, secondary interventions and follow-up requirements remain a significant issue. New devices are currently being studied in the U.S. and abroad and may significantly reduce complications and secondary interventions. PMID:26959727

  11. Abdominal aortic feminism.

    PubMed

    Mortimer, Alice Emily

    2014-01-01

    A 79-year-old woman presented to a private medical practice 2 years previously for an elective ultrasound screening scan. This imaging provided the evidence for a diagnosis of an abdominal aortic aneurysm (AAA) to be made. Despite having a number of recognised risk factors for an AAA, her general practitioner at the time did not follow the guidance set out by the private medical professional, that is, to refer the patient to a vascular specialist to be entered into a surveillance programme and surgically evaluated. The patient became symptomatic with her AAA, was admitted to hospital and found to have a tender, symptomatic, 6 cm leaking AAA. She consented for an emergency open AAA repair within a few hours of being admitted to hospital, despite the 50% perioperative mortality risk. The patient spent 4 days in intensive care where she recovered well. She was discharged after a 12 day hospital stay but unfortunately passed away shortly after her discharge from a previously undiagnosed gastric cancer. PMID:25398912

  12. 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

  13. Porous Organic Cage Thin Films and Molecular-Sieving Membranes.

    PubMed

    Song, Qilei; Jiang, Shan; Hasell, Tom; Liu, Ming; Sun, Shijing; Cheetham, Anthony K; Sivaniah, Easan; Cooper, Andrew I

    2016-04-01

    Porous organic cage molecules are fabricated into thin films and molecular-sieving membranes. Cage molecules are solution cast on various substrates to form amorphous thin films, with the structures tuned by tailoring the cage chemistry and processing conditions. For the first time, uniform and pinhole-free microporous cage thin films are formed and demonstrated as molecular-sieving membranes for selective gas separation. PMID:26800019

  14. Open aortic surgery after thoracic endovascular aortic repair.

    PubMed

    Coselli, Joseph S; Spiliotopoulos, Konstantinos; Preventza, Ourania; de la Cruz, Kim I; Amarasekara, Hiruni; Green, Susan Y

    2016-08-01

    In the last decade, thoracic endovascular aortic aneurysm repair (TEVAR) has emerged as an appealing alternative to the traditional open aortic aneurysm repair. This is largely due to generally improved early outcomes associated with TEVAR, including lower perioperative mortality and morbidity. However, it is relatively common for patients who undergo TEVAR to need a secondary intervention. In select circumstances, these secondary interventions are performed as an open procedure. Although it is difficult to assess the rate of open repairs after TEVAR, the rates in large series of TEVAR cases (>300) have ranged from 0.4 to 7.9 %. Major complications of TEVAR that typically necessitates open distal aortic repair (i.e., repair of the descending thoracic or thoracoabdominal aorta) include endoleak (especially type I), aortic fistula, endograft infection, device collapse or migration, and continued expansion of the aneurysm sac. Conversion to open repair of the distal aorta may be either elective (as for many endoleaks) or emergent (as for rupture, retrograde complicated dissection, malperfusion, and endograft infection). In addition, in select patients (e.g., those with a chronic aortic dissection), unrepaired sections of the aorta may progressively dilate, resulting in the need for multiple distal aortic repairs. Open repairs after TEVAR can be broadly classified as full extraction, partial extraction, or full salvage of the stent-graft. Although full and partial stent-graft extraction imply failure of TEVAR, such failure is generally absent in cases where the stent-graft can be fully salvaged. We review the literature regarding open repair after TEVAR and highlight operative strategies. PMID:27314956

  15. Caged oligonucleotides for studying biological systems

    PubMed Central

    Ruble, Brittani K.; Yeldell, Sean B.; Dmochowski, Ivan J.

    2015-01-01

    Light-activated (“caged”) compounds have been widely employed for studying biological processes with high spatial and temporal control. In the past decade, several new approaches for caging the structure and function of DNA and RNA oligonucleotides have been developed. This review focuses on caged oligonucleotides that incorporate site-specifically one or two photocleavable linkers, whose photolysis yields oligonucleotides with dramatic structural and functional changes. This technique has been employed by our laboratory and others to photoregulate gene expression in cells and living organisms, typically using near UV-activated organic chromophores. To improve capabilities for in vivo studies, we harnessed the rich inorganic photochemistry of ruthenium bipyridyl complexes to synthesize Ru-caged morpholino antisense oligonucleotides that remain inactive in zebrafish embryos until uncaged with visible light. Expanding into new caged oligonucleotide applications, our lab has developed Transcriptome In Vivo Analysis (TIVA) technology, which provides the first noninvasive, unbiased method for isolating mRNA from single neurons in brain tissues. TIVA-isolated mRNA can be amplified and then analyzed using next-generation sequencing (RNA-seq). PMID:25865001

  16. Busting out of the Teacher Cage

    ERIC Educational Resources Information Center

    Hess, Frederick M.

    2015-01-01

    The author lays out guidelines and suggestions for how teachers can actually become policy leaders, taken from his book, "The Cage-Busting Teacher" (Harvard Education Press, 2015). Teachers serious about leadership can get the ear of policy makers by leveraging their positional and moral authority--though they may need to be persistent…

  17. An Easy Synthesis of Two Cage Hydrocarbons.

    ERIC Educational Resources Information Center

    Dong, Dao Cong

    1982-01-01

    Describes a simple, three-step synthesis of two cage molecules, birdcage hydrocarbon (VIII) and its homologue, the homobirdcage hydrocarbon IX. Indicates that all products are easily purified and formed in high yields in this activity suitable for advanced undergraduate laboratory courses. (Author/JN)

  18. Stabilizing a 22 karat nanogolden cage

    NASA Astrophysics Data System (ADS)

    Wang, Q.; Sun, Q.; Jena, P.

    2009-11-01

    Since the discovery of C60 fullerene, considerable efforts have been devoted to find other elements with similar hollow cage structures. However, search for hollow metallic cages with a diameter similar to that of C60 fullerene has been elusive. We describe a procedure for the rational design of metallic cages by suitably choosing their size, composition, and charge state. A 22 karat nanogolden cage with a diameter of about 8.5 Å and consisting of 12 Al and 20 Au atoms is found to be metastable, which can be stabilized by embedding a Mn4 cluster. In contrast to bulk Mn, which is antiferromagnetic, and isolated Mn4 cluster, which is ferromagnetic with a giant magnetic moment of 20μB, the Mn4@Al12Au20 endohedral complex exhibits magnetic bistability with 0μB and 14μB configurations being energetically nearly degenerate. These results, based on density functional theory, open the door to design a novel class of endohedral complexes with possible applications.

  19. Stabilizing a 22 karat nanogolden cage.

    PubMed

    Wang, Q; Sun, Q; Jena, P

    2009-11-28

    Since the discovery of C(60) fullerene, considerable efforts have been devoted to find other elements with similar hollow cage structures. However, search for hollow metallic cages with a diameter similar to that of C(60) fullerene has been elusive. We describe a procedure for the rational design of metallic cages by suitably choosing their size, composition, and charge state. A 22 karat nanogolden cage with a diameter of about 8.5 A and consisting of 12 Al and 20 Au atoms is found to be metastable, which can be stabilized by embedding a Mn(4) cluster. In contrast to bulk Mn, which is antiferromagnetic, and isolated Mn(4) cluster, which is ferromagnetic with a giant magnetic moment of 20mu(B), the Mn(4)@Al(12)Au(20) endohedral complex exhibits magnetic bistability with 0mu(B) and 14mu(B) configurations being energetically nearly degenerate. These results, based on density functional theory, open the door to design a novel class of endohedral complexes with possible applications. PMID:19947688

  20. 50 CFR 648.75 - Cage identification.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... in accordance with 15 CFR part 904. (d) Return. Tags that have been rendered null and void must be... Atlantic Surf Clam and Ocean Quahog Fisheries § 648.75 Cage identification. Link to an amendment published... requirements apply to all vessels issued a Federal fishing permit for surf clams and ocean quahogs: (a)...

  1. Persistent Fifth Aortic Arch with Coarctation

    PubMed Central

    Kim, Sue Hyun; Choi, Eun-Suk; Cho, Sungkyu; Kim, Woong-Han

    2016-01-01

    Persistent fifth aortic arch (PFAA) is a rare congenital anomaly of the aortic arch frequently associated with other cardiovascular anomalies, such as tetralogy of Fallot and aortic arch coarctation or interruption. We report the case of a neonate with PFAA with coarctation who successfully underwent surgical repair. PMID:26889445

  2. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Maintenance of the CAGE... Maintenance of the CAGE file. (a) DLA Logistics Information Service will accept written requests for changes to CAGE files, other than name changes, from the following entities: (1) The entity identified by...

  3. Filtration effects due to bioassay cage design and screen type

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of bioassay cages in the efficacy assessment of specific compounds, application techniques and technologies is a common practice. There are a number of cage designs being used that range across a variety of cage shapes and sizes and mesh types. The objective of this work was to examine a r...

  4. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Maintenance of the CAGE... Maintenance of the CAGE file. (a) DLA Logistics Information Service will accept written requests for changes to CAGE files, other than name changes, from the following entities: (1) The entity identified by...

  5. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Maintenance of the CAGE... Maintenance of the CAGE file. (a) DLA Logistics Information Service will accept written requests for changes to CAGE files, other than name changes, from the following entities: (1) The entity identified by...

  6. 48 CFR 204.7202-1 - CAGE codes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...-free 1-888-352-9333); (B) The on-line access to the CAGE file through the Defense Logistics Information System; (C) The on-line access to the Defense Logistics Agency (DLA) CAGE file through the DLA Network or....39-M, Federal Logistics Information System (FLIS) Procedures Manual, prescribe use of CAGE codes....

  7. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Maintenance of the CAGE... Maintenance of the CAGE file. (a) DLA Logistics Information Service will accept written requests for changes to CAGE files, other than name changes, from the following entities: (1) The entity identified by...

  8. Aortic regurgitation caused by rupture of the abnormal fibrous band between the aortic valve and aortic wall.

    PubMed

    Minami, Hiroya; Asada, Tatsuro; Gan, Kunio; Yamada, Akitoshi; Sato, Masanobu

    2011-07-01

    This report documents the sudden onset of aortic regurgitation (AR) by an exceptional cause. A 68-year-old woman suddenly experienced general fatigue, and AR was diagnosed. One year later, we performed aortic valve replacement. At surgery, three aortic cusps with a larger noncoronary cusp had prolapsed along with a free-floating fibrous band that had previously anchored the cusp to the aortic wall. Its rupture had induced the sudden onset of AR. There was no sign of infectious endocarditis. We performed successful aortic valve replacement. PMID:21751110

  9. [MINIMALLY INVASIVE AORTIC VALVE REPLACEMENT].

    PubMed

    Tabata, Minoru

    2016-03-01

    Minimally invasive aortic valve replacement (MIAVR) is defined as aortic valve replacement avoiding full sternotomy. Common approaches include a partial sternotomy right thoracotomy, and a parasternal approach. MIAVR has been shown to have advantages over conventional AVR such as shorter length of stay and smaller amount of blood transfusion and better cosmesis. However, it is also known to have disadvantages such as longer cardiopulmonary bypass and aortic cross-clamp times and potential complications related to peripheral cannulation. Appropriate patient selection is very important. Since the procedure is more complex than conventional AVR, more intensive teamwork in the operating room is essential. Additionally, a team approach during postoperative management is critical to maximize the benefits of MIAVR. PMID:27295772

  10. Pseudoaneurysm of the aortic arch

    PubMed Central

    Lu, Yuan-Qiang; Yao, Feng; Shang, An-Dong; Pan, Jian

    2016-01-01

    Abstract Background: Pseudoaneurysm of the aortic arch is uncommonly associated with cancer, and is extremely rare in pulmonary cancer. Here, we report an unusual and successfully treated case of aortic arch pseudoaneurysm in a male patient with lung squamous cell carcinoma. Methods: A 64-year-old male patient was admitted to the Emergency Department, presenting with massive hemoptysis (>500 mL blood during the 12 hours prior to treatment). The diagnosis of aortic arch pseudoaneurysm was confirmed after inspection of computed tomographic angiography and three-dimensional reconstruction. We processed the immediate endovascular stent-grafting for this patient. Results: This patient recovered with no filling or enlargement of the pseudoaneurysm, no episodes of hemoptysis, and no neurological complications during the 4-week follow-up period. Conclusion: Herein, we compare our case with other cancer-related pseudoaneurysms in the medical literature and summarize the clinical features and treatment of this unusual case. PMID:27495079

  11. CAGEd-oPOSSUM: motif enrichment analysis from CAGE-derived TSSs

    PubMed Central

    Arenillas, David J.; Forrest, Alistair R. R.; Kawaji, Hideya; Lassmann, Timo; Wasserman, Wyeth W.; Mathelier, Anthony

    2016-01-01

    With the emergence of large-scale Cap Analysis of Gene Expression (CAGE) datasets from individual labs and the FANTOM consortium, one can now analyze the cis-regulatory regions associated with gene transcription at an unprecedented level of refinement. By coupling transcription factor binding site (TFBS) enrichment analysis with CAGE-derived genomic regions, CAGEd-oPOSSUM can identify TFs that act as key regulators of genes involved in specific mammalian cell and tissue types. The webtool allows for the analysis of CAGE-derived transcription start sites (TSSs) either provided by the user or selected from ∼1300 mammalian samples from the FANTOM5 project with pre-computed TFBS predicted with JASPAR TF binding profiles. The tool helps power insights into the regulation of genes through the study of the specific usage of TSSs within specific cell types and/or under specific conditions. Availability and Implementation: The CAGEd-oPOSUM web tool is implemented in Perl, MySQL and Apache and is available at http://cagedop.cmmt.ubc.ca/CAGEd_oPOSSUM. Contacts: anthony.mathelier@ncmm.uio.no or wyeth@cmmt.ubc.ca Supplementary information: Supplementary data are available at Bioinformatics online. PMID:27334471

  12. BIOMECHANICS OF ABDOMINAL AORTIC ANEURYSM

    PubMed Central

    Vorp, David A.

    2009-01-01

    Abdominal aortic aneurysm (AAA) is a condition whereby the terminal aorta permanently dilates to dangerous proportions, risking rupture. The biomechanics of AAA has been studied with great interest since aneurysm rupture is a mechanical failure of the degenerated aortic wall and is a significant cause of death in developed countries. In this review article, the importance of considering the biomechanics of AAA is discussed, and then the history and the state-of-the-art of this field is reviewed - including investigations into the biomechanical behavior of AAA tissues, modeling AAA wall stress and factors which influence it, and the potential clinical utility of these estimates in predicting AAA rupture. PMID:17254589

  13. CT of nontraumatic thoracic aortic emergencies.

    PubMed

    Bhalla, Sanjeev; West, O Clark

    2005-10-01

    Computed tomography (CT), especially multidetector row CT (MDCT), is often the preferred imaging test used for evaluation of nontraumatic thoracic aortic abnormalities. Unenhanced images, usually followed by contrast-enhanced arterial imaging, allow for rapid detailed aortic assessment. Understanding the spectrum of acute thoracic aortic conditions which may present similarly (aortic dissection, aneurysm rupture, penetrating atherosclerotic ulcer, intramural hematoma) will ensure that patients are diagnosed and treated appropriately. Familiarity with imaging protocols and potential mimics will prevent confusion of normal anatomy and variants with aortic disease. PMID:16274000

  14. Hydatid cyst involving the aortic arch.

    PubMed

    Apaydin, Anil Z; Oguz, Emrah; Zoghi, Mehdi

    2007-03-01

    We report a very rare case of primary mediastinal hydatid cyst which invaded the ascending aorta and the aortic arch which initially presented as a cranial mass. Aortic wall is a very unusual site for the hydatid cysts. To the best of our knowledge, this is the first reported case of hydatid cyst located within the aortic arch lumen. Patient underwent ascending aortic and hemiarch replacement under hypothermic circulatory arrest and removal of the cyst. Patient had an uneventful recovery and has been on follow-up. Although the literature data are very limited, we believe that the aortic procedure of choice should be graft interpositon rather than patch repair. PMID:17215134

  15. Biomechanical study of a hat type cervical intervertebral fusion cage

    PubMed Central

    Jia, Lian-Shun; Chen, Tong-Yi

    2006-01-01

    The purpose of this study was to evaluate the biomechanical effect of a hat type cervical intervertebral fusion cage (HCIFC). In this in vitro biomechanical study, 48 goat cervical spines (C2-5) were tested in flexion, extension, axial rotation, and lateral bending with a nondestructive stiffness method using a nonconstrained testing apparatus, and three-dimensional displacement was measured. Autologous iliac bone and cervical spine intervertebral fusion cage were implanted according to manufacturers’ information after complete discectomy (C3-4). Eight spines in each of the following groups were tested: intact, autologous iliac bone graft, Harms cage, SynCage C, carbon cage, and HCIFC. The mean apparent stiffness values were calculated from the corresponding load-displacement curves. Additionally, cage volume and volume-related stiffness were determined. The stiffness of the SynCage C was statistically greatest in all directions. After implantation of the HCIFC, flexion stiffness increased compared with that of the intact motion segment. There was no significant difference in stiffness between the HCIFC and carbon cage. The stiffness of the HCIFC was statistically higher than that of the Harms cage in axial rotation and significantly lower in flexion, extension, and lateral bending. Volume-related stiffness of all cages was higher than that of iliac bone graft. The Harms cage was highest in volume-related stiffness in all directions. The HCIFC can provide enough primary stability for cervical intervertebral fusion. PMID:16763843

  16. Comparison between Two Different Cervical Interbody Fusion Cages in One Level Stand-alone ACDF: Carbon Fiber Composite Frame Cage Versus Polyetheretherketone Cage

    PubMed Central

    Yoo, Minwook; Kim, Wook-Ha; Hyun, Seung-Jae; Jahng, Tae-Ahn; Kim, Hyun-Jib

    2014-01-01

    Objective The authors conducted a retrospective study to compare the implantation of carbon fiber composite frame cages (CFCFCs) to the implantation of polyetheretherketone (PEEK) cages after anterior cervical discectomy for cervical degenerative disc disease. In addition, the predictive factors that influenced fusion or subsidence were investigated. Methods A total of 58 patients with single-level degenerative disc disease were treated with anterior cervical discectomy and implantation of stand-alone cages; CFCFCs were used in 35 patients, and PEEK cages were used in 23 patients. Preoperative and postoperative radiological and clinical assessments were performed. Results During the mean follow-up period of 41 months, fusion occurred in 43 patients (74.1%), and subsidence developed in 18 patients (31.0%). Pain decreased in all patients, and the patients' satisfaction rate was 75.9%. Neither fusion nor subsidence was related to the clinical outcome. There were no significant differences in the clinical and radiological outcomes between the CFCFC and the PEEK cage groups. Smoking history (p=0.023) was significantly associated with pseudarthrosis, and cage height (≥7mm) (p=0.037) were significantly associated with subsidence. Conclusion The clinical and radiological results were similar between the CFCFC and the PEEK cage groups. Fusion or subsidence did not affect the clinical outcomes. Smoking history and cage height (≥7mm) were predictive factors for pseudarthrosis or subsidence in anterior cervical discectomy and fusion with stand-alone cages. PMID:25346758

  17. Visceral Infarction Following Aortic Surgery

    PubMed Central

    Johnson, Willard C.; Nabseth, Donald C.

    1974-01-01

    An experience with aortic surgery is reported which reveals that visceral ischemia is more frequent than expected and significantly contributes to operative mortality. Two of five deaths among 84 patients who had aorto-iliac occlusive disease and four of 40 deaths among 103 aneurysmectomies (both ruptured and elective) were related to visceral ischemia. A review of the literature reveals 99 cases of colonic ischemia in more than 6,100 cases of aortic surgery, an incidence of 1.5%. Only 10 cases of small bowel ischemia were recorded. The present experience with 9 cases of colon ischemia and one of small bowel ischemia is presented particularly with reference to pathophysiology and prevention. It is concluded that patients should be identified by appropriate angiography if considered a risk for visceral infarction, and, if present, visceral arterial reconstruction should be performed in addition to aortic reconstructive surgery. Colon infarction following aortic aneurysmal surgery is directly related to ligation of a patent IMA. Thus re-implantation of the patent IMA should be considered. ImagesFig. 1a. PMID:4277757

  18. Vascular airway compression management in a case of aortic arch and descending thoracic aortic aneurysm

    PubMed Central

    Kumar, Alok; Dutta, Vikas; Negi, Sunder; Puri, G. D.

    2016-01-01

    Airway compression due to distal aortic arch and descending aortic aneurysm repair has been documented. This case of tracheal and left main stem bronchus compression due to aortic aneurysm occurred in a 42-year-old man. The airway compression poses a challenge for the anesthesiologist in airway management during aortic aneurysm repair surgery. The fiber-optic bronchoscope is very helpful in decision-making both preoperatively and postoperatively in such cases. We report a case of airway compression in a 42-year-old patient who underwent elective distal aortic arch and descending aortic aneurysm repair. PMID:27397474

  19. Vascular airway compression management in a case of aortic arch and descending thoracic aortic aneurysm.

    PubMed

    Kumar, Alok; Dutta, Vikas; Negi, Sunder; Puri, G D

    2016-01-01

    Airway compression due to distal aortic arch and descending aortic aneurysm repair has been documented. This case of tracheal and left main stem bronchus compression due to aortic aneurysm occurred in a 42-year-old man. The airway compression poses a challenge for the anesthesiologist in airway management during aortic aneurysm repair surgery. The fiber-optic bronchoscope is very helpful in decision-making both preoperatively and postoperatively in such cases. We report a case of airway compression in a 42-year-old patient who underwent elective distal aortic arch and descending aortic aneurysm repair. PMID:27397474

  20. Aortic Root Enlargement with Ascending-to-Descending Aortic Bypass in Repair of Coarctation.

    PubMed

    Perry, Paul A; Young, Nilas

    2015-07-01

    Ascending-to-descending aortic bypass is a valuable technique for addressing coarctation of the aorta when additional cardiac procedures are indicated in adults. Among these, aortic valve replacement is one of the most commonly performed concomitant procedures, and there are instances in which aortic root enlargement is required. Herein, a novel technique is described for performing simultaneous ascending-to-descending aortic bypass in conjunction with aortic root enlargement which incorporates the bypass graft as part of the aortic root enlargement. PMID:26897826

  1. Screening Surface Contamination with BetaCage

    SciTech Connect

    Schnee, R. W.; Grant, D. R.; Poinar, K.; Ahmed, Z.; Golwala, S. R.

    2007-03-28

    Existing screening facilities are insufficiently sensitive to meet the needs of rare-event experiments for low-energy electron emitters and alpha-decaying isotopes. To provide such screening, the BetaCage will be a low-background, atmospheric-pressure neon drift chamber with unprecedented sensitivity to emitters of low-energy electrons and alpha particles. Minimization of the detector mass and use of radiopure materials reduce background events. The chamber design accepts nearly all alphas and low-energy electrons from the sample surface while allowing excellent rejection of residual backgrounds. A non-radiopure prototype is under construction to test the design. The BetaCage will provide new infrastructure for rare-event science as well as for a wider community that uses radioactive screening for areas including archaeology, biology, climatology, environmental science, geology, planetary science, and integrated-circuit quality control.

  2. Rotational and constitutional dynamics of caged supramolecules

    PubMed Central

    Kühne, Dirk; Klappenberger, Florian; Krenner, Wolfgang; Klyatskaya, Svetlana; Ruben, Mario; Barth, Johannes V.

    2010-01-01

    The confinement of molecular species in nanoscale environments leads to intriguing dynamic phenomena. Notably, the organization and rotational motions of individual molecules were controlled by carefully designed, fully supramolecular host architectures. Here we use an open 2D coordination network on a smooth metal surface to steer the self-assembly of discrete trimeric guest units, identified as noncovalently bound dynamers. Each caged chiral supramolecule performs concerted, chirality-preserving rotary motions within the template honeycomb pore, which are visualized and quantitatively analyzed using temperature-controlled scanning tunneling microscopy. Furthermore, with higher thermal energies, a constitutional system dynamics appears, which is revealed by monitoring repetitive switching events of the confined supramolecules’ chirality signature, reflecting decay and reassembly of the caged units. PMID:21098303

  3. Biology's built-in Faraday cages

    NASA Astrophysics Data System (ADS)

    Klee, Maurice M.

    2014-05-01

    Biological fluids are water-based, ionic conductors. As such, they have both high relative dielectric constants and substantial conductivities, meaning they are lossy dielectrics. These fluids contain charged molecules (free charges), whose movements play roles in essentially all cellular processes from metabolism to communication with other cells. Using the problem of a point source in air above a biological fluid of semi-infinite extent, the bound charges in the fluid are shown to perform the function of a fast-acting Faraday cage, which protects the interior of the fluid from external electric fields. Free charges replace bound charges in accordance with the fluid's relaxation time, thereby providing a smooth transition between the initial protection provided by the bound charges and the steady state protection provided by the free charges. The electric fields within the biological fluid are thus small for all times just as they would be inside a classical Faraday cage.

  4. Cage Destruction in Metal-Fullerene Clusters

    SciTech Connect

    Tast, F.; Malinowski, N.; Frank, S.; Heinebrodt, M.; Billas, I.M.; Martin, T.P.

    1996-10-01

    Mass spectrometric studies on free clusters composed of single fullerene molecules and transition metal atoms (C{sub 60}{ital M}{sub {ital x}} and C{sub 70}{ital M}{sub {ital x}}; {ital x}=0.150, {ital M}{element_of}{l_brace}Ti,V,Nb,Ta{r_brace}) reveal that they undergo a laser induced transformation from metal-fullerene clusters to metal carbide and metallo-carbohedrene clusters. Two types of fragmentation behavior are observed. Fullerenes doped with titanium or vanadium seem to be stable at low laser intensities, whereas tantalum and niobium severely destabilize the fullerene cage. Photofragmentation spectra of preselected C{sub 60}Ta{sub {ital x}} indicate that the C{sub 60} cage is destroyed for {ital x}{ge}3. {copyright} {ital 1996 The American Physical Society.}

  5. Porous Organic Cages for Sulfur Hexafluoride Separation.

    PubMed

    Hasell, Tom; Miklitz, Marcin; Stephenson, Andrew; Little, Marc A; Chong, Samantha Y; Clowes, Rob; Chen, Linjiang; Holden, Daniel; Tribello, Gareth A; Jelfs, Kim E; Cooper, Andrew I

    2016-02-10

    A series of porous organic cages is examined for the selective adsorption of sulfur hexafluoride (SF6) over nitrogen. Despite lacking any metal sites, a porous cage, CC3, shows the highest SF6/N2 selectivity reported for any material at ambient temperature and pressure, which translates to real separations in a gas breakthrough column. The SF6 uptake of these materials is considerably higher than would be expected from the static pore structures. The location of SF6 within these materials is elucidated by X-ray crystallography, and it is shown that cooperative diffusion and structural rearrangements in these molecular crystals can rationalize their superior SF6/N2 selectivity. PMID:26757885

  6. Decellularized aortic homografts for aortic valve and aorta ascendens replacement†

    PubMed Central

    Tudorache, Igor; Horke, Alexander; Cebotari, Serghei; Sarikouch, Samir; Boethig, Dietmar; Breymann, Thomas; Beerbaum, Philipp; Bertram, Harald; Westhoff-Bleck, Mechthild; Theodoridis, Karolina; Bobylev, Dmitry; Cheptanaru, Eduard; Ciubotaru, Anatol; Haverich, Axel

    2016-01-01

    OBJECTIVES The choice of valve prosthesis for aortic valve replacement (AVR) in young patients is challenging. Decellularized pulmonary homografts (DPHs) have shown excellent results in pulmonary position. Here, we report our early clinical results using decellularized aortic valve homografts (DAHs) for AVR in children and mainly young adults. METHODS This prospective observational study included all 69 patients (44 males) operated from February 2008 to September 2015, with a mean age of 19.7 ± 14.6 years (range 0.2–65.3 years). In 18 patients, a long DAH was used for simultaneous replacement of a dilated ascending aorta as an extended aortic root replacement (EARR). Four patients received simultaneous pulmonary valve replacement with DPH. RESULTS Thirty-nine patients (57%) had a total of 62 previous operations. The mean aortic cross-clamp time in isolated cases was 129 ± 41 min. There was 1 conduit-unrelated death. The mean DAH diameter was 22.4 ± 3.7 mm (range, 10–29 mm), the average peak gradient was 14 ± 15 mmHg and the mean aortic regurgitation grade (0.5 = trace, 1 = mild) was 0.6 ± 0.5. The mean effective orifice area (EOA) of 25 mm diameter DAH was 3.07 ± 0.7 cm2. DAH annulus z-values were 1.1 ± 1.1 at implantation and 0.7 ± 1.3 at the last follow-up. The last mean left ventricle ejection fraction and left ventricle end diastolic volume index was 63 ± 7% and 78 ± 16 ml/m2 body surface area, respectively. To date, no dilatation has been observed at any level of the graft during follow-up; however, the observational time is short (140.4 years in total, mean 2.0 ± 1.8 years, maximum 7.6 years). One small DAH (10 mm at implantation) had to be explanted due to subvalvular stenosis and developing regurgitation after 4.5 years and was replaced with a 17 mm DAH without complication. No calcification of the explanted graft was noticed intraoperatively and after histological analysis, which revealed extensive recellularization without inflammation

  7. MDCT evaluation of acute aortic syndrome (AAS).

    PubMed

    Valente, Tullio; Rossi, Giovanni; Lassandro, Francesco; Rea, Gaetano; Marino, Maurizio; Muto, Maurizio; Molino, Antonio; Scaglione, Mariano

    2016-05-01

    Non-traumatic acute thoracic aortic syndromes (AAS) describe a spectrum of life-threatening aortic pathologies with significant implications on diagnosis, therapy and management. There is a common pathway for the various manifestations of AAS that eventually leads to a breakdown of the aortic intima and media. Improvements in biology and health policy and diffusion of technology into the community resulted in an associated decrease in mortality and morbidity related to aortic therapeutic interventions. Hybrid procedures, branched and fenestrated endografts, and percutaneous aortic valves have emerged as potent and viable alternatives to traditional surgeries. In this context, current state-of-the art multidetector CT (MDCT) is actually the gold standard in the emergency setting because of its intrinsic diagnostic value. Management of acute aortic disease has changed with the increasing realization that endovascular therapies may offer distinct advantages in these situations. This article provides a summary of AAS, focusing especially on the MDCT technique, typical and atypical findings and common pitfalls of AAS, as well as recent concepts regarding the subtypes of AAS, consisting of aortic dissection, intramural haematoma, penetrating atherosclerotic ulcer and unstable aortic aneurysm or contained aortic rupture. MDCT findings will be related to pathophysiology, timing and management options to achieve a definite and timely diagnostic and therapeutic definition. In the present article, we review the aetiology, pathophysiology, clinical presentation, outcomes and therapeutic approaches to acute aortic syndromes. PMID:27033344

  8. Luminescent Cages: Pendant Emissive Units on [Pd2L4](4+) "Click" Cages.

    PubMed

    Elliott, Anastasia B S; Lewis, James E M; van der Salm, Holly; McAdam, C John; Crowley, James D; Gordon, Keith C

    2016-04-01

    The photophysics of a family of exo-functionalized [Pd2L4](4+) metallo-supramolecular cage architectures constructed from a tripyridyl 1,2,3-triazole backbone are reported. Several spectroscopic techniques are employed including both electronic (steady-state and transient absorption and emission) and vibrational (resonant and nonresonant Raman) methods. These experimental results are interpreted alongside simulated results from density functional theory calculations of the system's vibrational and electronic properties. The ligands and cages are shown to be essentially insulated from the exo-functionalization. They exhibit electronic transitions in the UV region and excited-state properties that are little affected by formation of the cage. Upon functionalization, characteristic Raman bands, electronic transitions, and emission bands associated with, and confined to, the substituent are observed. PMID:26991000

  9. Subtle-discrete aortic dissection without bulging of the aortic wall. A rare but lethal lesion.

    PubMed

    Kalogerakos, Paris Dimitrios; Kampitakis, Emmanouil; Pavlopoulos, Dionisios; Chalkiadakis, George; Lazopoulos, George

    2016-08-01

    We report a subtle-discrete aortic dissection, without bulging of the aortic wall or aneurysm or valve pathology or periaortic effusion, which resulted in a lethal cardiac tamponade to a 35-year-old male. PMID:27357491

  10. Non-Gaussian nature of glassy dynamics by cage to cage motion

    SciTech Connect

    Vorselaars, Bart; Lyulin, Alexey V.; Michels, M. A. J.; Karatasos, K.

    2007-01-15

    A model based on a single Brownian particle moving in a periodic effective field is used to understand the non-Gaussian dynamics in glassy systems of cage escape and subsequent recaging, often thought to be caused by a heterogeneous glass structure. The results are compared to molecular-dynamics simulations of systems with varying complexity: quasi-two-dimensional colloidlike particles, atactic polystyrene, and a dendritic glass. The model nicely describes generic features of all three topologically different systems, in particular around the maximum of the non-Gaussian parameter. This maximum is a measure for the average distance between cages.

  11. Type B Aortic Dissection with Abdominal Aortic Aneurysm Rupture 1 Year after Endovascular Repair of Abdominal Aortic Aneurysm.

    PubMed

    Daniel, Guillaume; Ben Ahmed, Sabrina; Warein, Edouard; Gallon, Arnaud; Rosset, Eugenio

    2016-05-01

    We report a patient who developed a type B aortic dissection and ruptured his aneurysmal sac 1 year after endovascular abdominal aortic aneurysm repair (EVAR), despite standard follow-up. This 79-year-old man was presented to emergency room with acute abdominal pain and an acute lower limb ischemia. Computed tomography scan showed an acute type B aortic dissection feeding the aneurysmal sac of the EVAR. The aneurysm rupture occurred during imaging. Type B aortic dissection is a rare cause of aneurysmal rupture after EVAR. The first postoperative computed tomography scan should maybe include the arch and the descending thoracic aorta to rule out an iatrogenic dissection after EVAR. PMID:26902937

  12. The impact of reduced frequency of cage changes on the health of mice housed in ventilated cages.

    PubMed

    Reeb-Whitaker, C K; Paigen, B; Beamer, W G; Bronson, R T; Churchill, G A; Schweitzer, I B; Myers, D D

    2001-01-01

    Our purpose in this investigation was to determine if we could reduce cage changing frequency without adversely affecting the health of mice. We housed mice at three different cage changing frequencies: 7, 14, and 21 days, each at three different cage ventilation rates: 30, 60 and 100 air changes per hour (ACH), for a total of nine experimental conditions. For each condition, we evaluated the health of 12 breeding pairs and 12 breeding trios of C57BL/6J mice for 7 months. Health was assessed by breeding performance, weanling weight and growth, plasma corticosterone levels, immune function, and histological examination of selected organs. Over a period of 4 months, we monitored the cage microenvironment for ammonia and carbon dioxide concentrations, relative humidity, and temperature one day prior to changing the cage. The relative humidity, carbon dioxide concentrations, and temperature of the cages at all conditions were within acceptable levels. Ammonia concentrations remained below 25 ppm (parts per million) in most cages, but, even at higher concentrations, did not adversely affect the health of mice. Frequency of cage changing had only one significant effect; pup mortality with pair matings was greater at the cage changing frequency of 7 days compared with 14 or 21 days. In addition, pup mortality with pair matings was higher at 30 ACH compared with other ventilation rates. In conclusion, under the conditions of this study, cage changes once every 14 days and ventilation rates of 60 ACH provide optimum conditions for animal health and practical husbandry. PMID:11201289

  13. Thoracic Aortic Dissection: Are Matrix Metalloproteinases Involved?

    PubMed Central

    Zhang, Xiaoming; Shen, Ying H.; LeMaire, Scott A.

    2010-01-01

    Thoracic aortic dissection, one of the major diseases affecting the aorta, carries a very high mortality rate. Improving our understanding of the pathobiology of this disease may help us develop medical treatments to prevent dissection and subsequent aneurysm formation and rupture. Dissection is associated with degeneration of the aortic media. Recent studies have shown increased expression and activation of a family of proteolytic enzymes—called matrix metalloproteinases (MMPs)—in dissected aortic tissue, suggesting that MMPs may play a major role in this disease. Inhibition of MMPs may be beneficial in reducing MMP-mediated aortic damage associated with dissection. This article reviews the recent literature and summarizes our current understanding of the role of MMPs in the pathobiology of thoracic aortic dissection. The potential importance of MMP inhibition as a future treatment of aortic dissection is also discussed. PMID:19476747

  14. Influence of 5 Different Caging Types and the Use of Cage-Changing Stations on Mouse Allergen Exposure

    PubMed Central

    Feistenauer, Susan; Sander, Ingrid; Schmidt, Jörg; Zahradnik, Eva; Raulf, Monika; Brielmeier, Markus

    2014-01-01

    Animal allergens constitute a serious health risk in laboratory animal facilities. To assess possibilities for allergen reduction by technical and organizational measures, we studied personnel exposure to mouse urinary aeroallergens in an animal facility with a holding capacity of 30,000 cages. Short-term (2 h) and intermediate-term (12 h) stationary samples (n = 107) and short-term (2 h) personnel samples (n = 119) were collected on polytetrafluorethylene filters by using air pumps. Long-term (14 d) stationary dust samples containing airborne allergens (n = 165) were collected with electrostatic dust fall collectors (EDC). Mouse allergens were quantified by ELISA. Personnel samples were collected during bedding disposal and refilling of clean cages as well as during cage changing with and without use of cage-changing station. Animal rooms were equipped with either open cages, cages with a soft filter top, cages with a rigid filter top (static microisolation caging), or with individually ventilated cages (IVC) with either a sealed or nonsealed lid, each in positive- or negative-pressure mode. Highest personnel allergen exposure was detected during cage change and emptying of soiled cages. Allergen concentrations were lowest in rooms with sealed IVC under positive or negative pressure, with unsealed IVC under negative pressure, and with static microisolation caging. The use of cage-changing stations and a vacuum bedding-disposal system reduced median personnel exposures 14- to 25-fold, respectively. Using sealed IVC and changing stations minimized allergen exposure, indicating that state-of-the-art equipment reduces exposure to mouse allergens and decreases health risks among animal facility personnel. PMID:25199090

  15. Mitochondria mediate septin cage assembly to promote autophagy of Shigella.

    PubMed

    Sirianni, Andrea; Krokowski, Sina; Lobato-Márquez, Damián; Buranyi, Stephen; Pfanzelter, Julia; Galea, Dieter; Willis, Alexandra; Culley, Siân; Henriques, Ricardo; Larrouy-Maumus, Gerald; Hollinshead, Michael; Sancho-Shimizu, Vanessa; Way, Michael; Mostowy, Serge

    2016-07-01

    Septins, cytoskeletal proteins with well-characterised roles in cytokinesis, form cage-like structures around cytosolic Shigella flexneri and promote their targeting to autophagosomes. However, the processes underlying septin cage assembly, and whether they influence S. flexneri proliferation, remain to be established. Using single-cell analysis, we show that the septin cages inhibit S. flexneri proliferation. To study mechanisms of septin cage assembly, we used proteomics and found mitochondrial proteins associate with septins in S. flexneri-infected cells. Strikingly, mitochondria associated with S. flexneri promote septin assembly into cages that entrap bacteria for autophagy. We demonstrate that the cytosolic GTPase dynamin-related protein 1 (Drp1) interacts with septins to enhance mitochondrial fission. To avoid autophagy, actin-polymerising Shigella fragment mitochondria to escape from septin caging. Our results demonstrate a role for mitochondria in anti-Shigella autophagy and uncover a fundamental link between septin assembly and mitochondria. PMID:27259462

  16. The effect of pesticide residue on caged mosquito bioassays.

    PubMed

    Barber, J A S; Greer, Mike; Coughlin, Jamie

    2006-09-01

    Wind tunnel experiments showed that secondary pickup of insecticide residue by mosquitoes in cage bioassays had a significant effect on mortality. Cage bioassays using adult Ochlerotatus taeniorhynchus (Wiedemann) investigated the effect of exposure time to a contaminated surface. Cages were dosed in a wind tunnel using the LC50 for naled (0.124 mg a.i./ml) and an LC25 (0.0772 mg a.i./ml) for naled. Half of the bioassay mosquitoes were moved directly into clean cages with the other half remaining in the sprayed, hence contaminated, cage. Treatment mortality was assessed at 8, 15, 30, 60, 120, 240, and 1,440 min postapplication. Cage contamination had a significant effect on mosquito mortality for both the LC25 and LC50 between 15 and 30 min postapplication. PMID:17067048

  17. Cervical aortic arch and a new type of double aortic arch. Report of a case.

    PubMed Central

    Cornali, M; Reginato, E; Azzolina, G

    1976-01-01

    A case of cervical aortic arch is reported. To the best of our knowledge, it is the first to be associated with a serious intracardiac anomaly. In addition, it is part of a new type of double aortic arch, caused by failure of reabsorption of both dorsal aortic roots and persistence of the fourth right and second (or third) left branchial arches. PMID:971387

  18. Treatment options for postdissection aortic aneurysms.

    PubMed

    Sobocinski, Jonathan; Patterson, Benjamin O; Clough, Rachel E; Spear, Rafaelle; Martin-Gonzalez, Teresa; Azzaoui, Richard; Hertault, Adrien; Haulon, Stéphan

    2016-04-01

    Aortic dissection is one of the most devastating catastrophes that can affect the aorta. Surgical treatment is proposed only when complications such as rupture or malperfusion occur. No clear consensus has been reached regarding the best therapy to prevent aortic rupture after the acute phase. We have performed a thorough review of the most recent literature on the strategies to treat patients in the chronic phase of aortic dissection. PMID:26771869

  19. Recurrent tamponade and aortic dissection in syphilis.

    PubMed

    Stansal, Audrey; Mirault, Tristan; Rossi, Aude; Dupin, Nicolas; Bruneval, Patrick; Bel, Alain; Azarine, Arshid; Minozzi, Catherine; Deman, Anne Laure; Messas, Emmanuel

    2013-11-01

    Syphilitic cardiovascular disease has been described since the 19th century, mainly on autopsy series. Major clinical manifestations are aortic aneurysm, aortic insufficiency, and coronary ostial stenosis. The diagnosis of syphilitic cardiovascular disease is based mainly on positive serologic tests and overt clinical manifestations. We present here a rare and unusual clinical presentation of a tertiary syphilis with recurrent tamponade and type B aortic dissection, whose positive diagnosis was made by polymerase chain reaction on pericardial fluid analysis. PMID:24182507

  20. Gold Sulfide Nanoclusters: A Unique Core-in-cage Structure

    SciTech Connect

    Jiang, Deen; Walter, Michael; Dai, Sheng

    2010-01-01

    By using a DFT-based basin-hopping method, we found putative global minima for three gold sulfide nanoclusters, observed in mass spectrometry, that all show a symmetric core-in-cage structure: a metallic Au core inside a cage with S as vertices and Au at the edges. This core-in-cage structure is distinct from bulk gold sulfide. This work fills the knowledge gap regarding the structure of gold sulfide nanoclusters of {approx}1 nm.

  1. Extended cage adjustable speed electric motors and drive packages

    DOEpatents

    Hsu, John S.

    1999-01-01

    The rotor cage of a motor is extended, a second stator is coupled to this extended rotor cage, and the windings have the same number of poles. The motor torque and speed can be controlled by either injecting energy into or extracting energy out from the rotor cage. The motor produces less harmonics than existing doubly-fed motors. Consequently, a new type of low cost, high efficiency drive is produced.

  2. Extended cage adjustable speed electric motors and drive packages

    DOEpatents

    Hsu, J.S.

    1999-03-23

    The rotor cage of a motor is extended, a second stator is coupled to this extended rotor cage, and the windings have the same number of poles. The motor torque and speed can be controlled by either injecting energy into or extracting energy out from the rotor cage. The motor produces less harmonics than existing doubly-fed motors. Consequently, a new type of low cost, high efficiency drive is produced. 12 figs.

  3. Aortic Aneurysm: Etiopathogenesis and Clinicopathologic Correlations

    PubMed Central

    2016-01-01

    Aortic aneurysm (AA) is one of the life-threatening aortic diseases, leading to aortic rupture of any cause including atherosclerotic and non-atherosclerotic diseases. AA is diagnosed in a variable proportion of patients with dilated aorta by imaging modality. The etiopathogenesis of AA remains unclear in many aortic diseases. Furthermore, although it may be difficult to explain all phenotypes of patients even if genetic mutation could be identified in some proteins such as smooth muscle cell α-actin (ACTA2), myosin heavy chain 11 (MYH11) or SMAD3, individualized consideration of these factors in each patient is essential on the basis of clinicopathological characteristics. PMID:27375798

  4. Practical genetics of thoracic aortic aneurysm.

    PubMed

    Elefteriades, John A; Pomianowski, Pawel

    2013-01-01

    This chapter will provide a practical look at the rapidly evolving field regarding the genetics of thoracic aortic aneurysm. It will start with a look at the history of the genetics of thoracic aortic aneurysm and will then move on to elucidating the discovery of familial patterns of thoracic aortic aneurysm. We will next review the Mendelian genetics of transmission of thoracic aortic aneurysm. We will move on to the molecular genetics at the DNA level and finish with a discussion of the molecular genetics at the RNA level, including a promising investigational "RNA Signature" test that we have been developing at Yale. PMID:23993238

  5. Brucellosis complicated by aortic valve endocarditis.

    PubMed

    Skillington, P D; McGiffin, D C; Kemp, R; Bett, J H; Holt, G; Forgan-Smith, R

    1988-12-01

    A 30 year old veterinary surgeon developed a febrile illness with serological evidence of Brucellosis. He was known to have aortic valve disease and during the course of the illness, the clinical features of endocarditis became evident, with a vegetation visible echocardiographically on the aortic valve. Because of persisting fever despite appropriate antibiotic therapy, aortic valve replacement with a viable cryopreserved allograft aortic valve was undertaken. Organisms consistent with Brucella species were demonstrated in the excised vegetation. The patient received a six week course of antibiotics and his post-operative course was uneventful. PMID:3250411

  6. Application of bicyclic and cage compounds

    NASA Technical Reports Server (NTRS)

    Clark, R. D.; Archuleta, B. S.

    1976-01-01

    The results of a literature survey of the field of bicyclic and cage compounds were presented, with the objective of identifying those types of compounds with unusual physical and chemical stability, and determining what practical applications have been found for these compounds. Major applications have been as polymers, polymer additives, medicinals, and pesticides. Lesser applications have included fuels, fuel additives, lubricants, lubricant additives, and perfumes. Several areas where further work might be useful were also outlined; these are primarily in the areas of polymers, polymer additives, medicinals, and synthetic lubricants.

  7. Horizontal transmission of Salmonella and Campylobacter among caged and cage-free laying hens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In each of five trials, laying hens (56-72 wk-of-age) were challenged orally, intracolonally, and intravaginally with Salmonella and Campylobacter. One wk post inoculation, challenged hens (n=3) were commingled with non-challenged hens (n=12) in conventional wire cages, on all wire slats, or on all...

  8. Potential for horizontal transmission of Salmonella and Campylobacter among caged and cage free laying hens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nine hens were inoculated orally and intravaginally with a marker strain of Salmonella and Campylobacter at 56 wk-of-age and housed in individual cages in isolation. Challenged hens were comingled with non-challenged hens 2 wk post-inoculation, at a ratio of 1 challenged hen per 4 non-challenged he...

  9. Horizontal transmission of Salmonella and Campylobacter among caged and cage-free laying hens.

    PubMed

    Hannah, J F; Wilson, J L; Cox, N A; Richardson, L J; Cason, J A; Bourassa, D V; Buhr, R J

    2011-12-01

    In each of five sequential trials, laying hens (56-72 wk of age) were challenged with Salmonella and Campylobacter, and 1 wk postinoculation, the challenged hens (n = 3) were commingled with nonchallenged hens (n = 12) in conventional wire cages, on all-wire slats, or on all-shavings floor housing systems. After 12 days, challenged and nonchallenged hens were euthanatized for sample collection. Ceca were aseptically collected from all hens, and the spleen, liver/gallbladder (LGB), lower (LRT) and upper (URT) reproductive tracts, and ovarian follicles (mature and immature) were collected from only the challenged hens after commingling. Samples were divided equally and cultured separately for Salmonella and Campylobacter. Differences in the horizontal transmission of the challenge Salmonella to nonchallenged hens housed in cages (12%), on slats (15%), and on shavings (14%) were not significantly different (P > 0.05) from the challenged pen-mate hens over the five trials. However, with the inclusion of residual environmental Salmonella, the recovery of Salmonella from nonchallenged hens housed in cages was lowest at 15%, intermediate for hens on slats at 20%, and highest for hens on shavings at 38%. Among challenged hens housed in cages, Salmonella was recovered from only 27% of the cecum and LRT samples. From challenged hens housed on slats, Salmonella was recovered from 38% of the cecum, 12% of the spleen, 19% of the LGB, 44% of the LRT, and 19% of the URT samples. From challenged hens housed on shavings, Salmonella was recovered from 31% of the cecum; 15% of the spleen, LGB, and URT; and 31% of the LRT samples. Horizontal transmission of Campylobacter among nonchallenged pen-mate hens was significantly lower for hens housed in cages at 28% than for hens on shavings at 47%, with hens on slats being intermediate at 36%. For challenged hens housed in cages, Campylobacter was recovered from 27% of the cecum, 13% of the LRT, 7% of the URT, and 17% of the follicle

  10. [Surgical aspects of acute aortic dissection].

    PubMed

    Laas, J; Heinemann, M; Jurmann, M; Borst, H G

    1992-12-01

    This paper highlights some of the surgical aspects of acute aortic dissections such as: emergency diagnosis, indications for surgery, reconstructive operative techniques, malperfusion phenomena and necessity for follow-up. Aortic dissection is caused by an intimal tear, called the "entry", and subsequent splitting of the media by the stream of blood. Two lumina are thus created, which may communicate through "re-entries". As this creates severe weakness of the aortic wall, rupture and/or dilatation are the imminent dangers of acute aortic dissection. Acute aortic dissection type A, by definition involving the ascending aorta (Figures 1 and 2), is an absolute indication for emergency surgical treatment, because its natural history shows an extremely poor outcome (Figure 3). Due to impending (intrapericardial) aortic rupture, it may be necessary to limit diagnostic procedures to a minimum. Transesophageal echocardiography is the method of choice for establishing a quick, precise and reliable diagnosis (Figure 4). In stable patients, computed tomography gives additional information about aortic diameters or sites of extrapericardial perforation. Digital subtraction angiography (DSA) shows perfusion of the lumina and dependent organs. The surgical strategy in acute aortic dissection type A aims at replacement of the ascending aorta. Reconstructive techniques have to be considered, especially in aortic valve regurgitation without annuloectasia (Figures 5 and 6). In recent times, the use of GRF tissue glue has reduced the need for teflon felt. Involvement of the aortic arch should be treated aggressively up to the point of total arch replacement in deep hypothermic circulatory arrest as part of the primary procedure (Figure 7). Malperfusion phenomena of aortic branches remain risk-factors.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1483624

  11. WUnicuspid Aortic Valve- An Uncommon Anomaly With a Common Presentation.

    PubMed

    Sitwala, Puja; Abusara, Ashraf; Ladia, Vatsal; Ladia, Vatsal; Panchal, Hemang B; Raudat, Charles; Paul, Timir K

    2016-01-01

    Unicuspid aortic valve (UAV), which is a rare congenital anomaly, usually presents as aortic stenosis and/or aortic regurgitation. Here we present a case of UAV co-existent with an ascending aortic aneurysm. A 26-year-old male with no significant past medical history presented to the hospital after two episodes of syncope. Transthoracic echocardiogram showed an ejection fraction of 62%, severely stenotic aortic valve, and moderate aortic regurgitation. Computed tomography revealed calcification of the aortic valve, compatible with aortic stenosis and aneurysm of the ascending aorta measuring 4.3 cm in diameter. He underwent successful aortic valve replacement and repair of ascending aortic aneurysm. He recovered well without any complications. This case suggests that any young patient who presents with syncope, aortic stenosis would be a differential and further workup by any available non-invasive modality needs to be performed. PMID:27383857

  12. Pregnancy after aortic root replacement in Loeys-Dietz syndrome: High risk of aortic dissection.

    PubMed

    Braverman, Alan C; Moon, Marc R; Geraghty, Patrick; Willing, Marcia; Bach, Christopher; Kouchoukos, Nicholas T

    2016-08-01

    Loeys-Dietz syndrome due to mutations in TGFBR1 and 2 is associated with early and aggressive aortic aneurysm and branch vessel disease. There are reports of uncomplicated pregnancy in this condition, but there is an increased risk of aortic dissection and uterine rupture. Women with underlying aortic root aneurysm are cautioned about the risk of pregnancy-related aortic dissection. Prophylactic aortic root replacement is recommended in women with aortopathy and aortic root dilatation to lessen the risk of pregnancy. There is limited information in the literature about the outcomes of pregnancy after root replacement in Loeys-Dietz syndrome. We present a case series of three women with Loeys-Dietz syndrome who underwent elective aortic root replacement for aneurysm disease and subsequently became pregnant and underwent Cesarean section delivery. Each of these women were treated with beta blockers throughout pregnancy. Surveillance echocardiograms and noncontrast MRA studies during pregnancy remained stable demonstrating no evidence for aortic enlargement. Despite the normal aortic imaging and careful observation, two of the three women suffered acute aortic dissection in the postpartum period. These cases highlight the high risk of pregnancy following aortic root replacement in Loeys-Dietz syndrome. Women with this disorder are recommended to be counseled accordingly. © 2016 Wiley Periodicals, Inc. PMID:27125181

  13. When and how to replace the aortic root in type A aortic dissection

    PubMed Central

    Leshnower, Bradley G.

    2016-01-01

    Management of aortic root pathology during repair of acute type A aortic dissection (TAAD) requires a comprehensive evaluation of the patient’s anatomy, demographics, comorbidities and physiologic status at the time of emergent operative intervention. Surgical options include conservative repair of the root (CRR) (with or without replacement of the aortic valve), replacement of the native valve and aortic root using a composite valve-conduit and valve sparing root replacement (VSRR). The primary objective of this review is to provide data for surgeons to aid in their decision-making process regarding management of the aortic root during repair of TAAD. No time or language restrictions were imposed and references of the selected studies were checked for additional relevant citations. Multiple retrospective reviews have demonstrated equivalent operative mortality between aortic root repair and replacement during TAAD. There is a higher incidence of aortic root reintervention with aortic root repair compared to aortic root replacement (ARR). Experienced, high-volume aortic centers have demonstrated the safety of VSRR in young, hemodynamically stable patients presenting with TAAD. In conclusion, aortic root repair can safely be performed in the vast majority of patients with TAAD. Despite the increased surgical complexity, ARR does not increase operative mortality and improves the freedom from root reintervention. VSRR can be performed in highly selected populations of patients with TAAD with durable mid-term valve function. PMID:27563551

  14. When and how to replace the aortic root in type A aortic dissection.

    PubMed

    Leshnower, Bradley G; Chen, Edward P

    2016-07-01

    Management of aortic root pathology during repair of acute type A aortic dissection (TAAD) requires a comprehensive evaluation of the patient's anatomy, demographics, comorbidities and physiologic status at the time of emergent operative intervention. Surgical options include conservative repair of the root (CRR) (with or without replacement of the aortic valve), replacement of the native valve and aortic root using a composite valve-conduit and valve sparing root replacement (VSRR). The primary objective of this review is to provide data for surgeons to aid in their decision-making process regarding management of the aortic root during repair of TAAD. No time or language restrictions were imposed and references of the selected studies were checked for additional relevant citations. Multiple retrospective reviews have demonstrated equivalent operative mortality between aortic root repair and replacement during TAAD. There is a higher incidence of aortic root reintervention with aortic root repair compared to aortic root replacement (ARR). Experienced, high-volume aortic centers have demonstrated the safety of VSRR in young, hemodynamically stable patients presenting with TAAD. In conclusion, aortic root repair can safely be performed in the vast majority of patients with TAAD. Despite the increased surgical complexity, ARR does not increase operative mortality and improves the freedom from root reintervention. VSRR can be performed in highly selected populations of patients with TAAD with durable mid-term valve function. PMID:27563551

  15. 1/f Noise Inside a Faraday Cage

    SciTech Connect

    Handel, Peter H.; George, Thomas F.

    2009-04-23

    We show that quantum 1/f noise does not have a lower frequency limit given by the lowest free electromagnetic field mode in a Faraday cage, even in an ideal cage. Indeed, quantum 1/f noise comes from the infrared-divergent coupling of the field with the charges, in their joint nonlinear system, where the charges cause the field that reacts back on the charges, and so on. This low-frequency limitation is thus not applicable for the nonlinear system of matter and field in interaction. Indeed, this nonlinear system is governed by Newton's laws, Maxwell's equations, in general also by the diffusion equations for particles and heat, or reaction kinetics given by quantum matrix elements. Nevertheless, all the other quantities can be eliminated in principle, resulting in highly nonlinear integro-differential equations for the electromagnetic field only, which no longer yield a fundamental frequency. Alternatively, we may describe this through the presence of an infinite system of subharmonics. We show how this was proven early in the classical and quantum domains, adding new insight.

  16. Hybrid uranyl-carboxyphosphonate cage clusters.

    PubMed

    Adelani, Pius O; Ozga, Michael; Wallace, Christine M; Qiu, Jie; Szymanowski, Jennifer E S; Sigmon, Ginger E; Burns, Peter C

    2013-07-01

    Two new hybrid uranyl-carboxyphosphonate cage clusters built from uranyl peroxide units were crystallized from aqueous solution under ambient conditions in approximately two months. The clusters are built from uranyl hexagonal bipyramids and are connected by employing a secondary metal linker, the 2-carboxyphenylphosphonate ligand. The structure of cluster A is composed of a ten-membered uranyl polyhedral belt that is capped on either end of an elongated cage by five-membered rings of uranyl polyhedra. The structure of cluster B consists of 24 uranyl cations that are arranged into 6 four-membered rings of uranyl polyhedra. Four of the corresponding topological squares are fused together to form a sixteen-membered double uranyl pseudobelt that is capped on either end by 2 topological squares. Cluster A crystallizes over a wide pH range of 4.6-6.8, while cluster B was isolated under narrower pH range of 6.9-7.8. Studies of their fate in aqueous solution upon dissolution of crystals by electrospray ionization mass spectrometry (ESI-MS) and small-angle X-ray scattering (SAXS) provide evidence for their persistence in solution. The well-established characteristic fingerprint from the absorption spectra of the uranium(VI) cations disappears and becomes a nearly featureless peak; nonetheless, the two compounds fluoresce at room temperature. PMID:23763595

  17. [Unicuspid Aortic Valve Stenosis Combined with Aortic Coarctation;Report of a Case].

    PubMed

    Kubota, Takehiro; Wakasa, Satoru; Shingu, Yasushige; Matsui, Yoshiro

    2016-06-01

    Unicuspid aortic valve in an adult is extremely rare. In addition, 90% of the patients with aortic coarctation are reported to die before the age 50. A 60-year-old woman was admitted to our hospital for further examination of exertional dyspnea which had begun one year before. She had been under medical treatment for hypertension since early thirties, and had been also diagnosed with moderate aortic stenosis at 50 years of age. She was at 1st diagnosed with aortic coarctation combined with bicuspid aortic valve stenosis. The aortic valve was then found unicuspid and was replaced under cardiopulmonary bypass with perfusion to both the ascending aorta and the femoral artery. Repair of aortic coarctation was performed 3 months later through left thoracotomy without extracorporeal circulation due to the rich collateral circulation. She had no postoperative complications, and hypertension as well as ankle-brachial index improved to the normal levels. PMID:27246132

  18. Rheumatic aortic stenosis in young patients presenting with combined aortic and mitral stenosis.

    PubMed Central

    Vijayaraghavan, G; Cherian, G; Krishnaswami, S; SUKUMAR, I P; John, S

    1977-01-01

    This report describes 30 patients under the age of 30 years with rheumatic aortic stenosis, presenting with combined aortic and mitral stenosis. Three patients had additional tricuspid stenosis. Twenty-eight patients gave a history of rheumatic polyarthritis. The diagnosis was confirmed by right and left heart catheterisation in all. The murmur of aortic stenosis was not initially present in 8 out of 10 patients in congestive heart failure. Aortic valve calcification was not seen. Cineangiography showed a tricuspid aortic valve in all, unlike congenital aortic stenosis. A unique feature of this group was the raised pulmonary vascular resistance in 87 per cent of the patients. The present study shows that patients in India developing aortic stenosis after rheumatic fever do so early in the natural history of the disease. PMID:849390

  19. Mitral and aortic regurgitation following transcatheter aortic valve replacement

    PubMed Central

    Szymański, Piotr; Hryniewiecki, Tomasz; Dąbrowski, Maciej; Sorysz, Danuta; Kochman, Janusz; Jastrzębski, Jan; Kukulski, Tomasz; Zembala, Marian

    2016-01-01

    Objective To analyse the impact of postprocedural mitral regurgitation (MR), in an interaction with aortic regurgitation (AR), on mortality following transcatheter aortic valve implantation (TAVI). Methods To assess the interaction between MR and AR, we compared the survival rate of patients (i) without both significant MR and AR versus (ii) those with either significant MR or significant AR versus (iii) with significant MR and AR, all postprocedure. 381 participants of the Polish Transcatheter Aortic Valve Implantation Registry (166 males (43.6%) and 215 females (56.4%), age 78.8±7.4 years) were analysed. Follow-up was 94.1±96.5 days. Results Inhospital and midterm mortality were 6.6% and 10.2%, respectively. Significant MR and AR were present in 16% and 8.1% patients, including 3.1% patients with both significant MR and AR. Patients with significant versus insignificant AR differed with respect to mortality (log rank p=0.009). This difference was not apparent in a subgroup of patients without significant MR (log rank p=0.80). In a subgroup of patients without significant AR, there were no significant differences in mortality between individuals with versus without significant MR (log rank p=0.44). Significant MR and AR had a significant impact on mortality only when associated with each other (log rank p<0.0001). At multivariate Cox regression modelling concomitant significant MR and AR were independently associated with mortality (OR 3.2, 95% CI 1.54 to 5.71, p=0.002). Conclusions Significant MR or AR postprocedure, when isolated, had no impact on survival. Combined MR and AR had a significant impact on a patient's prognosis. PMID:26908096

  20. Self-assembly of highly luminescent heteronuclear coordination cages.

    PubMed

    Schmidt, Andrea; Hollering, Manuela; Han, Jiaying; Casini, Angela; Kühn, Fritz E

    2016-08-01

    Exo-functionalized Pd2L4 cage compounds with attached Ru(ii) pyridine complexes were prepared via coordination-driven self-assembly. Unlike most of the previously reported palladium(ii) cages, one of these metallocages exhibits an exceptionally high quantum yield of 66%. The presented approach is promising to obtain luminescent coordination complexes for various applications. PMID:27436541

  1. Problem Drinking Screening in College Students Using the CAGE.

    ERIC Educational Resources Information Center

    Heck, Edward J.; And Others

    The CAGE instrument is a 4-item questionnaire used for routine and rapid screening of alcohol problems. The term "CAGE" is an acronym with each letter representing one of the four items that comprise the instrument. A positive endorsement of two or more items is considered to be the threshold score, indicating the possibility of a drinking…

  2. Teaching in the Institutional Cage: Metaphor and Collateral Oppression

    ERIC Educational Resources Information Center

    Noël Smith, Becky L.

    2014-01-01

    This analysis is a philosophical exploration of Marilyn Frye's metaphor of the cage and Patricia Hill Collins' theory of intersecting oppressions. It argues that social structures and forms of oppressive knowledge make up the individual wires on each person's cage and that these work to confine individuals, particularly those in the…

  3. 48 CFR 204.7202-1 - CAGE codes.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... access to the Defense Logistics Agency (DLA) CAGE file through the DLA Network or dial-up capability; or... Logistics Information Service assigns or records and maintains CAGE codes to identify commercial and... Volume 7 of DoD 4100.39-M, Federal Logistics Information System (FLIS) Procedures Manual, prescribe...

  4. 48 CFR 204.7202-1 - CAGE codes.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... access to the Defense Logistics Agency (DLA) CAGE file through the DLA Network or dial-up capability; or... Logistics Information Service assigns or records and maintains CAGE codes to identify commercial and... Volume 7 of DoD 4100.39-M, Federal Logistics Information System (FLIS) Procedures Manual, prescribe...

  5. 48 CFR 204.7202-1 - CAGE codes.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... access to the Defense Logistics Agency (DLA) CAGE file through the DLA Network or dial-up capability; or... Logistics Information Service assigns or records and maintains CAGE codes to identify commercial and... Volume 7 of DoD 4100.39-M, Federal Logistics Information System (FLIS) Procedures Manual, prescribe...

  6. 48 CFR 204.7202-1 - CAGE codes.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... System for Award Management (SAM) database (see FAR subpart 4.11) and does not have a CAGE code, DLA... for registration in the SAM database. Foreign registrants must obtain a North Atlantic Treaty Organization CAGE (NCAGE) code in order to register in the SAM database. NCAGE codes may be obtained from...

  7. A Locust Cage and Hatchery from Plastic Aquarium Tanks

    ERIC Educational Resources Information Center

    Stoneman, C. F.; And Others

    1973-01-01

    Describes how to construct a locust cage from two plastic aquaria and four coffee jars with plastic lids. Its advantages over a conventional locust cage include the inexpensive cost, lack of breakable glass, ease of cleaning, and visibility from all angles. (JR)

  8. Morphosynthesis of cubic silver cages on monolithic activated carbon.

    PubMed

    Wang, Fei; Zhao, Hong; Lai, Yijian; Liu, Siyu; Zhao, Binyuan; Ning, Yuesheng; Hu, Xiaobin

    2013-11-14

    Cubic silver cages were prepared on monolithic activated carbon (MAC) pre-absorbed with Cl(-), SO4(2-), or PO4(3-) anions. Silver insoluble salts served as templates for the morphosynthesis of silver cages. The silver ions were reduced by reductive functional groups on MAC micropores through a galvanic cell reaction mechanism. PMID:24080952

  9. Caging Mechanism for a drag-free satellite position sensor

    NASA Technical Reports Server (NTRS)

    Hacker, R.; Mathiesen, J.; Debra, D. B.

    1976-01-01

    A disturbance compensation system for satellites based on the drag-free concept was mechanized and flown, using a spherical proof mass and a cam-guided caging mechanism. The caging mechanism controls the location of the proof mass for testing and constrains it during launch. Design requirements, design details, and hardware are described.

  10. Abnormal Behavior in Relation to Cage Size in Rhesus Monkeys

    ERIC Educational Resources Information Center

    Paulk, H. H.; And Others

    1977-01-01

    Examines the effects of cage size on stereotyped and normal locomotion and on other abnormal behaviors in singly caged animals, whether observed abnormal behaviors tend to co-occur, and if the development of an abnormal behavior repertoire leads to reduction in the number of normal behavior categories. (Author/RK)

  11. Polymers containing borane or carborane cage compounds and related applications

    DOEpatents

    Bowen, III, Daniel E.; Eastwood, Eric A.

    2012-06-05

    Polymers comprising residues of borane and/or carborane cage compound monomers having at least one polyalkoxy silyl substituent. Such polymers can further comprise one or more reactive matrices and/or co-monomers covalently bound with the cage compound monomer residues. Methods of making and applications for using such polymers are also disclosed.

  12. Bearings use dry self-lubricating cage materials

    NASA Technical Reports Server (NTRS)

    Anderson, W. J.; Glenn, D. C.; Scribbe, H. W.

    1968-01-01

    Rolling element bearings in spacecraft mechanical systems use solid lubricant composites of polytetrafluoroethylene in the bearing cage which functions as the lubricant reservoir. The cage spaces the rolling elements equally and provides the lubricant at the bearing load-carrying surface.

  13. Ammonia Levels and Urine-Spot Characteristics as Cage-Change Indicators for High-Density Individually Ventilated Mouse Cages.

    PubMed

    Washington, Ida M; Payton, Mark E

    2016-01-01

    Mouse cage and bedding changes are potentially stressful to mice and are also labor- and resource-intensive. These changes are often performed on a calendar-based schedule to maintain a clean microenvironment and limit the concentrations of ammonia to which mice and workers are exposed. The current study sought to establish a performance-based approach to mouse cage-changing that uses urine spot characteristics as visual indicators of intracage ammonia levels. Colorimetric ammonia indicators were used to measure ammonia levels in individually-ventilated cages (IVC) housing male or female mice (n =5 per cage) of various strains at 1 to 16 d after cage change. Urine spot characteristics were correlated with ammonia levels to create a visual indicator of the cage-change criterion of 25 ppm ammonia. Results demonstrated a consistent increase in ammonia levels with days since cage change, with cages reaching the cage-change criterion at approximately 10 d for IVC containing male mice and 16 d for those with female mice. Ammonia levels were higher for male than female mice but were not correlated with mouse age. However, urine spot diameter, color, and edge characteristics were strongly correlated with ammonia levels. Husbandry practices based on using urine spot characteristics as indicators of ammonia levels led to fewer weekly cage changes and concomitant savings in labor and resources. Therefore, urine spot characteristics can be used as visual indicators of intracage ammonia levels for use of a performance (urine spot)-based approach to cage-changing frequency that maintains animal health and wellbeing. PMID:27177558

  14. Intraoperative tracking of aortic valve plane.

    PubMed

    Nguyen, D L H; Garreau, M; Auffret, V; Le Breton, H; Verhoye, J P; Haigron, P

    2013-01-01

    The main objective of this work is to track the aortic valve plane in intra-operative fluoroscopic images in order to optimize and secure Transcatheter Aortic Valve Implantation (TAVI) procedure. This paper is focused on the issue of aortic valve calcifications tracking in fluoroscopic images. We propose a new method based on the Tracking-Learning-Detection approach, applied to the aortic valve calcifications in order to determine the position of the aortic valve plane in intra-operative TAVI images. This main contribution concerns the improvement of object detection by updating the recursive tracker in which all features are tracked jointly. The approach has been evaluated on four patient databases, providing an absolute mean displacement error less than 10 pixels (≈2mm). Its suitability for the TAVI procedure has been analyzed. PMID:24110703

  15. Bicuspid Aortic Valve: Unlocking the Morphogenetic Puzzle.

    PubMed

    Longobardo, Luca; Jain, Renuka; Carerj, Scipione; Zito, Concetta; Khandheria, Bijoy K

    2016-08-01

    Although bicuspid aortic valve is the most common congenital abnormality, it is perhaps erroneous to consider this disease one clinical entity. Rather, it may be useful to consider it a cluster of diseases incorporating different phenotypes, etiologies, and pathogenesis. Discussion of bicuspid aortic valve can be difficult because there is no clear consensus on a phenotypic description among authors, and many classification schemes have been proposed. The literature suggests that different phenotypes have different associations and clinical manifestations. In addition, recent studies suggest a genetic basis for the disease, yet few genes have so far been described. Furthermore, recent scientific literature has been focusing on the increased risk of aortic aneurysms, but the pathogenesis of bicuspid aortic valve aortopathy is still unclear. The aim of this paper is to review the current evidence about the unsolved issues around bicuspid aortic valve. PMID:27059385

  16. Acute aortic dissection in pregnant women.

    PubMed

    Yang, Zhaohua; Yang, Shouguo; Wang, Fangshun; Wang, Chunsheng

    2016-05-01

    Acute aortic dissection occurring during pregnancy represents a lethal risk to both the mother and fetus. Management of parturient with acute aortic dissection is complex. We report our experience of two pregnancies with type A acute aortic dissection. One patient is a 31-year-old pregnant woman (33rd gestational week) with a bicuspid aortic valve and the other is a 32-year-old pregnant woman (30th gestational week) with the Marfan syndrome. In both cases, a combined emergency operation consisting of Cesarean section, total hysterectomy prior to corrective surgery for aortic dissection was successfully performed within a relatively short period of time after the onset. Both patients' postoperative recovery was uneventful, and we achieved a favorable maternal and fetal outcome. PMID:25085319

  17. Performance and welfare of rabbit does in various caging systems.

    PubMed

    Mikó, A; Matics, Zs; Gerencsér, Zs; Odermatt, M; Radnai, I; Nagy, I; Szendrő, K; Szendrő, Zs

    2014-07-01

    The objective of the study was to compare production and welfare of rabbit does and their kits housed in various types of cages. Female rabbits were randomly allocated to four groups with the following cage types: CN: common wire-mesh flat-deck cage, without footrest; CF: cage similar to the CN but with plastic footrest; ECWP: enlarged cage with wire-mesh platform; and ECPP: extra enlarged cage with plastic-mesh platform. All does were inseminated on the same day, 11 days after kindlings. Reproductive performance was evaluated during the first five consecutive kindlings. Severity of sore hocks was scored at each insemination. Location preference of the does and the platform usage of their kits were evaluated. Kindling rate, litter size (total born, born alive, alive at 21 and 35 days) and kit mortality were not significantly influenced by the cage types. The litter weight at 21 days was higher in ECWP and ECPP cages than in the CF group (3516, 3576 and 3291 g, respectively; P2.5 cm) and 3 to 4 (3=callus opened, cracks present; 4=wounds) were 58%, 60%, 78% and 48%, and 0%, 5%, 0% and 48% in groups ECPP, ECWP, CF and CN, respectively. Higher number of daily nest visits was observed for CF does than for ECWP does (12.5 v. 5.9; P2/day) was higher in the CF group than in the ECWP group (12.1 v. 3.2%; P<0.01). Within large cages, the does were observed on the platform more frequently in the ECPP cages compared with the ECWP cages (56.9% v. 31.7%; P<0.001). Similarly, 2.7% and 0.2% of kits at 21 days of age, and 33.2% and 5.2% of kits at 28 days of age, were found on the platforms of ECPP and ECWP cages, respectively. In conclusion, cages larger than the conventional ones improved kits' weaning weight, plastic footrests and plastic-mesh platforms in conventional and/or large cages reduced sore hocks' problems, plastic-mesh platforms were more used by both does and kits compared with the wire-mesh platforms. PMID:26263030

  18. Entropic cages for trapping DNA near a nanopore

    NASA Astrophysics Data System (ADS)

    Liu, Xu; Skanata, Mirna Mihovilovic; Stein, Derek

    2015-02-01

    Nanopores can probe the structure of biopolymers in solution; however, diffusion makes it difficult to study the same molecule for extended periods. Here we report devices that entropically trap single DNA molecules in a 6.2-femtolitre cage near a solid-state nanopore. We electrophoretically inject DNA molecules into the cage through the nanopore, pause for preset times and then drive the DNA back out through the nanopore. The saturating recapture time and high recapture probability after long pauses, their agreement with a convection-diffusion model and the observation of trapped DNA under fluorescence microscopy all confirm that the cage stably traps DNA. Meanwhile, the cages have 200 nm openings that make them permeable to small molecules, like the restriction endonuclease we use to sequence-specifically cut trapped DNA into fragments whose number and sizes are analysed upon exiting through the nanopore. Entropic cages thus serve as reactors for chemically modifying single DNA molecules.

  19. A Triphasic Sorting System: Coordination Cages in Ionic Liquids.

    PubMed

    Grommet, Angela B; Bolliger, Jeanne L; Browne, Colm; Nitschke, Jonathan R

    2015-12-01

    Host-guest chemistry is usually carried out in either water or organic solvents. To investigate the utility of alternative solvents, three different coordination cages were dissolved in neat ionic liquids. By using (19) F NMR spectroscopy to monitor the presence of free and bound guest molecules, all three cages were demonstrated to be stable and capable of encapsulating guests in ionic solution. Different cages were found to preferentially dissolve in different phases, allowing for the design of a triphasic sorting system. Within this system, three coordination cages, namely Fe4 L6 2, Fe8 L12 3, and Fe4 L4 4, each segregated into a distinct layer. Upon the addition of a mixture of three different guests, each cage (in each separate layer) selectively bound its preferred guest. PMID:26494225

  20. Aortic Aging in ESRD: Structural, Hemodynamic, and Mortality Implications.

    PubMed

    London, Gérard M; Safar, Michel E; Pannier, Bruno

    2016-06-01

    Aging incurs aortic stiffening and dilation, but these changes are less pronounced in peripheral arteries, resulting in stiffness and geometry gradients influencing progression of the forward and reflected pressure waves. Because premature arterial aging is observed in ESRD, we determined the respective roles of stiffness and aortic geometry gradients in 73 controls and 156 patients on hemodialysis. We measured aortic pulse wave velocity (PWV) and brachial PWV to evaluate the stiffness gradient [(brachial PWV/aortic PWV)(0.5)] and ascending aortic and aortic bifurcation diameters to assess aortic taper (ascending aortic diameter/aortic bifurcation diameter). The global reflection coefficient was estimated from characteristic impedance and vascular resistance. Cox proportional hazard models were used to determine mortality risk. The age-associated increase in aortic PWV was higher in patients (P<0.001). In controls, aortic ascending and bifurcation diameters increased with age, with an unchanged aortic taper. In patients on hemodialysis, age did not associate with increased ascending aortic diameter but did associate with increased aortic bifurcation diameter and decreased aortic taper, both of which also associated with abdominal aortic calcifications and smaller global reflection coefficient (P<0.001). In patients, multivariate models revealed all-cause and cardiovascular mortality associated with age, aortic PWV, and aortic bifurcation diameter with high specificity and sensitivity. Using stiffness gradient, aortic taper, or global reflection coefficient in the model produced similar results. Thus, whereas aortic stiffness is a known independent predictor of mortality, these results indicate the importance of also evaluating the aortic geometry in patients on hemodialysis. PMID:26475595

  1. Eggshell bacterial contamination of non-washed and washed eggs from caged and cage-free hens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was conducted to evaluate the microbiology of non-washed and washed table eggs obtained from caged and cage-free laying hens housed on either all shavings or all wire slat environments. Both Hy-Line W-37 white and Hy-Line brown strains were used. On each of four replication sample days ...

  2. Eggshell bacterial levels of non-washed and washed eggs from caged and cage-free hens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The bacteria levels of non-washed and washed eggs obtained from caged and cage-free laying hens housed on either all shavings or all wire slat floors were determined. On eight sample days (from 22 to 52 weeks at 4 week intervals), 20 eggs were collected from each pen (n=120/sample day). Ten eggs p...

  3. Giant Thoracic Aneurysm Following Valve Replacement for Bicuspid Aortic Valve.

    PubMed

    Tran, Cao; Ul Haq, Ehtesham; Nguyen, Ngoc; Omar, Bassam

    2015-01-01

    Bicuspid aortic valve is a common congenital anomaly associated with aortopathy, which can cause aortic root dilatation, necessitating regular screening if the aortic root is > 4.0 cm. Despite the low absolute incidence of aortic complications associated with bicuspid aortic valve in the general population, the consequences of such complications for an individual patient can be devastating. Herein we propose a balanced algorithm that incorporates recommendations from the three major guidelines for follow-up imaging of the aortic root and ascending thoracic aorta in patients with a bicuspid aortic valve, maintaining the current recommendations with regard to surgical thresholds. PMID:26827748

  4. Protein Cages as Containers for Gold Nanoparticles.

    PubMed

    Liu, Aijie; Verwegen, Martijn; de Ruiter, Mark V; Maassen, Stan J; Traulsen, Christoph H-H; Cornelissen, Jeroen J L M

    2016-07-01

    Abundant and highly diverse, viruses offer new scaffolds in nanotechnology for the encapsulation, organization, or even synthesis of novel materials. In this work the coat protein of the cowpea chlorotic mottle virus (CCMV) is used to encapsulate gold nanoparticles with different sizes and stabilizing ligands yielding stable particles in buffered solutions at neutral pH. The sizes of the virus-like particles correspond to T = 1, 2, and 3 Caspar-Klug icosahedral triangulation numbers. We developed a simple one-step process enabling the encapsulation of commercially available gold nanoparticles without prior modification with up to 97% efficiency. The encapsulation efficiency is further increased using bis-p-(sufonatophenyl)phenyl phosphine surfactants up to 99%. Our work provides a simplified procedure for the preparation of metallic particles stabilized in CCMV protein cages. The presented results are expected to enable the preparation of a variety of similar virus-based colloids for current focus areas. PMID:27135176

  5. Caged Protein Nanoparticles for Drug Delivery

    PubMed Central

    Molino, Nicholas M.; Wang, Szu-Wen

    2014-01-01

    Caged protein nanoparticles possess many desirable features for drug delivery, such as ideal sizes for endocytosis, non-toxic biodegradability, and the ability to functionalize at three distinct interfaces (external, internal, and inter-subunit) using the tools of protein engineering. Researchers have harnessed these attributes by covalently and non-covalently loading therapeutic molecules through mechanisms that facilitate release within specific microenvironments. Effective delivery depends on several factors, including specific targeting, cell uptake, release kinetics, and systemic clearance. The innate ability of the immune system to recognize and respond to proteins has recently been exploited to deliver therapeutic compounds with these platforms for immunomodulation. The diversity of drugs, loading/release mechanisms, therapeutic targets, and therapeutic efficacy are discussed in this review. PMID:24832078

  6. Electrofriction method of manufacturing squirrel cage rotors

    DOEpatents

    Hsu, John S.

    2005-04-12

    A method of making a squirrel cage rotor of copper material for use in AC or DC motors, includes forming a core with longitudinal slots, inserting bars of conductive material in the slots, with ends extending out of opposite ends of the core, and joining the end rings to the bars, wherein the conductive material of either the end rings or the bars is copper. Various methods of joining the end rings to the bars are disclosed including electrofriction welding, current pulse welding and brazing, transient liquid phase joining and casting. Pressure is also applied to the end rings to improve contact and reduce areas of small or uneven contact between the bar ends and the end rings. Rotors made with such methods are also disclosed.

  7. In-situ bioassays using caged bivalves

    SciTech Connect

    Salazar, M.H.; Salazar, S.M.

    1995-12-31

    It is important to make the distinction between chemical measurements to assess bioaccumulation potential versus biological measurements to assess potential bioeffects because bioaccumulation is not a bioeffect. Caging provides a unique opportunity to make synoptic measurements of each and facilitates making these measurements over space and time. Measuring bioaccumulation in resident and transplanted bivalves has probably been the most frequently used form of an in-situ bioassay because bivalves concentrate chemicals in their tissues. They are also easy to collect, cage, and measure. The authors have refined bivalve bioassay methods by minimizing the size range of test animals, making repetitive measurements of the same individuals, and standardizing test protocols for a variety of applications. They are now attempting to standardize criteria for accepting and interpreting data in the same way that laboratory bioassays have been standardized. Growth measurements can serve two purposes in this assessment strategy: (1) An integrated biological response endpoint that is easily quantifiable and with significance to the population, and (2) A means of calibrating bioaccumulation by assessing the relative health and physiological state of tissues that have accumulated the chemicals. In general, the authors have found the highest bioconcentration factors associated with the highest growth rates, the highest concentrations ({micro}g/g) of chemicals in juvenile mussels, and the highest chemical content ({micro}g/animal) in adult mussels. Without accounting for possible dilution of chemical concentrations by tissue growth or magnification through degrowth, contaminant concentrations can be misleading. Examples are provided for the Sudbury River in Massachusetts (Elliptio complanata), San Diego Bay (Mytilus galloprovincialis), and the Harbor Island Superfund Site in Puget Sound (Mytilus trossulus).

  8. Quadricuspid aortic valve with ruptured sinus of Valsalva.

    PubMed

    Akerem Khan, Shamruz Khan; Tamin, Syahidah Syed; Burkhart, Harold M; Araoz, Philip A; Young, Phillip M

    2013-02-01

    We present a case of a 24-year-old woman who was diagnosed with quadricuspid aortic valve with ruptured sinus of Valsalva. Quadricuspid aortic valve is a rare congenital cardiac anomaly. The recognition of quadricuspid aortic valve has clinical significance as it causes aortic valve dysfunction, and is often associated with other congenital cardiac abnormalities. We showed the important role of multimodality imaging in diagnosing a quadricuspid aortic valve associated with ruptured sinus of Valsalva. PMID:22874066

  9. Aortic valve allografts in sheep

    PubMed Central

    Borrie, John; Hill, G. L.

    1968-01-01

    Some of the mechnical and biological problems surrounding the use of fresh allograft inverted aortic valves as mitral valve substitutes are described. Certain aspects of the problem have been studied experimentally. In three sheep `fresh' aortic valve allografts were inserted, using cardiopulmonary bypass, into the main pulmonary artery, and were observed from 5 to 7 months after operation. The animals survived normally. Their normal pulmonary valves remained in situ. The technique is described. At subsequent necropsy, macroscopically the valves were found to be free from vegetation, and the cusps were pliable and apparently normal. Microscopically, the supporting allograft myocardium showed necrosis and early calcification. The valve cusp showed hyalinization of collagen, although beneath the endocardium this hyalinized collagen contained moderate numbers of fibroblasts with no evidence of proliferation. The endocardium and arterial intima of the allograft showed evidence of ingrowth from adjacent normal host endocardial tissues. The allograft itself was invested in a loose layer of fibro-fatty tissue, which, in view of the necrotic state of the graft myocardium, could well have been a reparative reaction rather than a homograft reaction. It is concluded that, although the cusps could function normally, the necrosis of the myocardium might in time lead to late failure of the graft. Further studies with the valve inserted at mitral level are indicated. Images PMID:5656757

  10. Aortic Stenosis and Vascular Calcifications in Alkaptonuria

    PubMed Central

    Hannoush, Hwaida; Introne, Wendy J.; Chen, Marcus Y.; Lee, Sook-Jin; O'Brien, Kevin; Suwannarat, Pim; Kayser, Michael A.; Gahl, William A.; Sachdev, Vandana

    2011-01-01

    Alkaptonuria is a rare metabolic disorder of tyrosine catabolism in which homogentisic acid (HGA) accumulates and is deposited throughout the spine, large joints, cardiovascular system, and various tissues throughout the body. In the cardiovascular system, pigment deposition has been described in the heart valves, endocardium, pericardium, aortic intima and coronary arteries. The prevalence of cardiovascular disease in patients with alkaptonuria varies in previous reports . We present a series of 76 consecutive adult patients with alkaptonuria who underwent transthoracic echocardiography between 2000 and 2009. A subgroup of 40 patients enrolled in a treatment study underwent non-contrast CT scans and these were assessed for vascular calcifications. Six of the 76 patients had aortic valve replacement. In the remaining 70 patients, 12 patients had aortic sclerosis and 7 patients had aortic stenosis. Unlike degenerative aortic valve disease, we found no correlation with standard cardiac risk factors. There was a modest association between the severity of aortic valve disease and joint involvement, however, we saw no correlation with urine HGA levels. Vascular calcifications were seen in the coronaries, cardiac valves, aortic root, descending aorta and iliac arteries. These findings suggest an important role for echocardiographic screening of alkaptonuria patients to detect valvular heart disease and cardiac CT to detect coronary artery calcifications. PMID:22100375

  11. The Effects of Positioning of Transcatheter Aortic Valve on Fluid Dynamics of the Aortic Root

    PubMed Central

    Su, Jimmy L; Kheradvar, Arash

    2015-01-01

    Transcatheter aortic valve implantation is a novel treatment for severe aortic valve stenosis. Due to the recent use of this technology and the procedural variability, there is very little data that quantifies the hemodynamic consequences of variations in valve placement. Changes in aortic wall stresses and fluid retention in the sinuses of Valsalva can have a significant effect on the clinical response a patient has to the procedure. By comprehensively characterizing complex flow in the sinuses of Valsalva using Digital Particle Image Velocimetry and an advanced heart flow simulator, various positions of a deployed transcatheter valve with respect to a bioprosthetic aortic valve (valve-in-valve) were tested in vitro. Displacements of the transcatheter valve were axial and directed below the simulated native valve annulus. It was determined that for both blood residence time and aortic Reynolds stresses, it is optimal to have the annulus of the transcatheter valve deployed as close to the aortic valve annulus as possible. PMID:25010918

  12. Balloon aortic valvuloplasty as a treatment option in the era of transcatheter aortic valve implantation.

    PubMed

    Costopoulos, Charis; Sutaria, Nilesh; Ariff, Ben; Fertleman, Michael; Malik, Iqbal; Mikhail, Ghada W

    2015-05-01

    Aortic valve stenosis is the commonest encountered valvular pathology and a frequent cause of morbidity and mortality in cases of severe stenosis. Definitive treatment has traditionally been offered in the form of surgical aortic valve replacement in patients with an acceptable surgical risk and more recently with the less invasive transcatheter aortic valve implantation (TAVI) in those where surgery is not a viable option. Prior to the introduction of TAVI, inoperable patients were treated medically and where appropriate with balloon aortic valvuloplasty, a procedure which although effective only provided short-term relief and was associated with high complication rates especially during its infancy. Here we discuss whether balloon aortic valvuloplasty continues to have a role in contemporary clinical practice in an era where significant advances have been achieved in the fields of surgical aortic valve replacement, TAVI and postoperative care. PMID:25865236

  13. A library of protein cage architectures as nanomaterials.

    PubMed

    Flenniken, M L; Uchida, M; Liepold, L O; Kang, S; Young, M J; Douglas, T

    2009-01-01

    Virus capsids and other structurally related cage-like proteins such as ferritins, dps, and heat shock proteins have three distinct surfaces (inside, outside, interface) that can be exploited to generate nanomaterials with multiple functionality by design. Protein cages are biological in origin and each cage exhibits extremely homogeneous size distribution. This homogeneity can be used to attain a high degree of homogeneity of the templated material and its associated property. A series of protein cages exhibiting diversity in size, functionality, and chemical and thermal stabilities can be utilized for materials synthesis under a variety of conditions. Since synthetic approaches to materials science often use harsh temperature and pH, it is an advantage to utilize protein cages from extreme environments. In this chapter, we review recent studies on discovering novel protein cages from harsh natural environments such as the acidic thermal hot springs at Yellowstone National Park (YNP) and on utilizing protein cages as nano-scale platforms for developing nanomaterials with wide range of applications from electronics to biomedicine. PMID:19198571

  14. Effect of TLIF Cage Placement on In Vivo Kinematics

    PubMed Central

    Castellvi, Alejandro D.; Thampi, Shankar K.; Cook, Daniel J.; Yeager, Matthew S.; Yao, Yuan; Zou, Qing; Whiting, Donald M.; Oh, Michael Y.; Prostko, Edward R.

    2015-01-01

    Background The influence of interbody cage positioning on clinical outcomes following lumbar interbody fusion is not well understood, though it has been hypothesized to play a significant role in stability of the treated level. The purpose of this study was to evaluate any correlations between cage placement in TLIF procedures and post-operative kinematics. Methods Thirteen patients who had previously undergone a TLIF procedure were evaluated using the Vertebral Motion Analysis (VMA) system, an automated fluoroscopic method of tracking kinematics in vivo. Upright and recumbent bending platforms were used to guide patients through a set range of motion (ROM) standing up and lying down, respectively, in both flexion-extension (FE) and lateral bending (LB). Intervertebral ROM was measured via fluoroscopic images captured sequentially throughout the movement. DICOM images acquired by the VMA system were used to calculate cage positioning. Intra-rater and inter-rater reliability of TLIF cage position were also assessed. Results Statistically significant correlations were noted between sagittal cage position and lying LB (r = -0.583, p = 0.047), and coronal cage positioning with both standing (r = 0.672, p = 0.012) and lying LB (r = 0.632, p = 0.027). Additionally, the correlation between sagittal cage position and standing FE was trending towards significance (r = -0.542, p = 0.055). Conclusions The intuitive correlation between coronal cage position and both standing and lying lateral bending ROM is supported by the data from this study, suggesting placement closer to midline is optimal for stability. Additionally, the VMA system appears to be a sensitive and repeatable means to obtain information on postoperative kinematic outcomes. Further work to establish the relationship between cage placement, these kinematic outcomes and, potentially, functional pain outcomes seems to be warranted based on the results obtained here. PMID:26273556

  15. Endovascular Repair of Thoracic Aortic Aneurysms

    PubMed Central

    Findeiss, Laura K.; Cody, Michael E.

    2011-01-01

    Degenerative aneurysms of the thoracic aorta are increasing in prevalence; open repair of descending thoracic aortic aneurysms is associated with high rates of morbidity and mortality. Repair of isolated descending thoracic aortic aneurysms using stent grafts was introduced in 1995, and in an anatomically suitable subgroup of patients with thoracic aortic aneurysm, repair with endovascular stent graft provides favorable outcomes, with decreased perioperative morbidity and mortality relative to open repair. The cornerstones of successful thoracic endovascular aneurysm repair are appropriate patient selection, thorough preprocedural planning, and cautious procedural execution, the elements of which are discussed here. PMID:22379281

  16. Bearing-cage frictional instability - A mechanical model

    SciTech Connect

    Rivera, M.P. )

    1991-01-01

    Bearing-cage frictional instability is analyzed by means of a simple mechanistic model. This model considers the frictional dynamic aspects of the bearing cage. The investigation of the motion-stability of this model is based on the concept of Liapunov functions. It is shown that the bearing-cage operation is frictionally stable whenever the friction force (combined solid and fluid) slope is negative and whenever a condition on the slope satisfies an inequality to be established. A simulated test shows the existence of a speed threshold on the onset of frictional stability. 8 refs.

  17. Beam-induced graphitic carbon cage transformation from sumanene aggregates

    SciTech Connect

    Fujita, Jun-ichi Tachi, Masashi; Murakami, Katsuhisa; Sakurai, Hidehiro; Morita, Yuki; Higashibayashi, Shuhei; Takeguchi, Masaki

    2014-01-27

    We found that electron-beam irradiation of sumanene aggregates strongly enhanced their transformation into a graphitic carbon cage, having a diameter of about 20 nm. The threshold electron dose was about 32 mC/cm{sup 2} at 200 keV, but the transformation is still induced at 20 keV. The transformation sequence suggested that the cage was constructed accompanied by the dynamical movement of the transiently linked sumanene molecules in order to pile up inside the shell. Thus, bond excitation in the sumanene molecules rather than a knock-on of carbon atoms seems to be the main cause of the cage transformation.

  18. Metabolic Cage for a Space Flight Model in the Rat

    NASA Technical Reports Server (NTRS)

    Harper, Jennifer S.; Mulenburg, Gerald M.; Evans, Juli; Navidi, Meena; Wolinsky, Ira; Arnaud, Sara B.

    1994-01-01

    The new cage facilitates the collection of 24-h specimens of separated urine and feces apparently uncontaminated by food, as required for precise nutritional and metabolic studies, while maintaining the large floor area and suspension method of Holton's design (3). Although the cage was evaluated, using 6-month-old rats weighing 408 to 488 g, it can be easily adjusted for smaller rats. It also was successfully used to collect post-flight urine after the recent Spacelab Life Sciences-2 space shuttle flight. With its flexibility and ease of use, this new cage design adds a new tool to study the physiologic effects of simulated space flight and other disuse conditions.

  19. Endohedral dynamics of push-pull rotor-functionalized cages.

    PubMed

    Krick, Marcel; Holstein, Julian; Würtele, Christian; Clever, Guido H

    2016-08-16

    A series of [Pd2L4] coordination cages featuring endohedral functionalities in central backbone positions was synthesized. Although attached via C[double bond, length as m-dash]C double bonds, the substituents behave as molecular rotors. This is explained by their pronounced donor-acceptor character which lowers rotational barriers and allows for electronic control over the spinning rates inside the cage. The dynamic behaviour of the free ligands, assembled cages and host-guest complexes is compared with the aid of NMR experiments, X-ray structure analysis and molecular modelling. PMID:27484435

  20. Management of Traumatic Aortic and Splenic Rupture in a Patient With Ascending Aortic Aneurysm.

    PubMed

    Topcu, Ahmet Can; Ciloglu, Ufuk; Bolukcu, Ahmet; Dagsali, Sabri

    2016-08-01

    Traumatic aortic rupture is rupture of all or part of the aortic wall, mostly resulting from blunt trauma to the chest. The most common site of rupture is the aortic isthmus. Traumatic rupture of the ascending aorta is rare. A 62-year-old man with a family history of ascending aortic aneurysm was referred to our hospital after a motor vehicle accident. He had symptoms of cardiogenic shock. A contrast-enhanced computed tomographic scan revealed rupture of the proximal ascending aorta and an ascending aortic aneurysm with a diameter of 55 mm at the level of the sinuses of Valsalva. Transthoracic echocardiography at the bedside revealed severe aortic valvular insufficiency. We performed a successful Bentall procedure. During postoperative recovery, the patient experienced a cerebrovascular accident. Transesophageal echocardiography did not reveal thrombosis of the mechanical prosthesis. The patient's symptoms resolved in time, and he was discharged from the hospital on postoperative day 47 without any sequelae. He has been symptom free during a 6-month follow-up period. We suggest that individuals who have experienced blunt trauma to the chest and have symptoms of traumatic aortic rupture and a known medical history of ascending aortic aneurysm should be evaluated for a rupture at the ascending aorta and the aortic isthmus. PMID:27449463

  1. Stroke Volume estimation using aortic pressure measurements and aortic cross sectional area: Proof of concept.

    PubMed

    Kamoi, S; Pretty, C G; Chiew, Y S; Pironet, A; Davidson, S; Desaive, T; Shaw, G M; Chase, J G

    2015-08-01

    Accurate Stroke Volume (SV) monitoring is essential for patient with cardiovascular dysfunction patients. However, direct SV measurements are not clinically feasible due to the highly invasive nature of measurement devices. Current devices for indirect monitoring of SV are shown to be inaccurate during sudden hemodynamic changes. This paper presents a novel SV estimation using readily available aortic pressure measurements and aortic cross sectional area, using data from a porcine experiment where medical interventions such as fluid replacement, dobutamine infusions, and recruitment maneuvers induced SV changes in a pig with circulatory shock. Measurement of left ventricular volume, proximal aortic pressure, and descending aortic pressure waveforms were made simultaneously during the experiment. From measured data, proximal aortic pressure was separated into reservoir and excess pressures. Beat-to-beat aortic characteristic impedance values were calculated using both aortic pressure measurements and an estimate of the aortic cross sectional area. SV was estimated using the calculated aortic characteristic impedance and excess component of the proximal aorta. The median difference between directly measured SV and estimated SV was -1.4ml with 95% limit of agreement +/- 6.6ml. This method demonstrates that SV can be accurately captured beat-to-beat during sudden changes in hemodynamic state. This novel SV estimation could enable improved cardiac and circulatory treatment in the critical care environment by titrating treatment to the effect on SV. PMID:26736434

  2. Liverpool Aortic Surgery Symposium V: New Frontiers in Aortic Disease and Surgery

    PubMed Central

    Bashir, Mohamad; Fok, Matthew; Shaw, Matthew; Field, Mark; Kuduvalli, Manoj; Desmond, Michael; Harrington, Deborah; Rashid, Abbas; Oo, Aung

    2014-01-01

    Aortic aneurysm disease is a complex condition that requires a multidisciplinary approach in management. The innovation and collaboration among vascular surgery, cardiothoracic surgery, interventional radiology, and other related specialties is essential for progress in the management of aortic aneurysms. The Fifth Liverpool Aortic Surgery Symposium that was held in May 2013 aimed at bringing national and international experts from across the United Kingdom and the globe to deliver their thoughts, applications, and advances in aortic and vascular surgery. In this report, we present a selected short synopsis of the key topics presented at this symposium. PMID:26798724

  3. Hybrid Thoracic Endovascular Aortic Repair for Intercostal Patch Aneurysm after Thoracoabdominal Aortic Replacement

    PubMed Central

    Yoshitake, Akihiro; Hachiya, Takashi; Okamoto, Kazuma; Hirano, Akinori; Kasai, Mio; Akamatsu, Yuta; Oka, Hidetoshi; Shimizu, Hideyuki

    2015-01-01

    We report a case of hybrid thoracic endovascular aortic repair for intercostal patch aneurysm after thoracoabdominal aortic replacement. Eighteen years ago, a 63-year-old woman with Marfan syndrome had undergone thoracoabdominal aortic replacement with reimplantation of the intercostal artery in an island fashion. Follow-up computed tomography (CT) revealed a remaining intercostal patch aneurysm of diameter 60 mm 17 years after the last operation. Hybrid thoracic endovascular aortic repair for exclusion of this intercostal patch aneurysm was successfully performed, with visceral artery bypasses. Postoperative CT showed no anastomotic stenosis or endoleak. PMID:26730265

  4. Minimally Invasive Transcatheter Aortic Valve Replacement (TAVR)

    MedlinePlus Videos and Cool Tools

    Watch a Broward Health surgeon perform a minimally invasive Transcatheter Aortic Valve Replacement (TAVR) Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2016 BroadcastMed, Inc. All rights reserved.

  5. A rare cause of recurrent aortic dissection.

    PubMed

    Agrawal, Yashwant; Gupta, Vishal

    2016-07-01

    We report the case of a 19-year-old man with a history of Loeys-Dietz syndrome (LDS), which was diagnosed when he had a Stanford type A aortic dissection. He also had multiple aneurysms including ones in the innominate, right common carotid, and right internal mammary arteries. He had had multiple procedures including Bentall's procedure, repeat sternotomy with complete arch and valve replacement, and coil embolization of internal mammary artery aneurysm in the past. His LDS was characterized by gene mutation for transforming growth factor-β receptor 1. He presented to our facility with sudden onset of back pain, radiating to the right shoulder and chest. He was diagnosed with Stanford type B aortic dissection and underwent thoracic aorta endovascular repair for his aortic dissection. This case represents the broad spectrum of pathology associated with LDS where even with regular surveillance and aggressive medical management the patient developed Stanford B aortic dissection. PMID:27358537

  6. Nanobacteria-associated calcific aortic valve stenosis.

    PubMed

    Jelic, Tomislav M; Chang, Ho-Huang; Roque, Rod; Malas, Amer M; Warren, Stafford G; Sommer, Andrei P

    2007-01-01

    Calcific aortic valve stenosis is the most common valvular disease in developed countries, and the major reason for operative valve replacement. In the US, the current annual cost of this surgery is approximately 1 billion dollars. Despite increasing morbidity and mortality, little is known of the cellular basis of the calcifications, which occur in high-perfusion zones of the heart. The case is presented of a patient with calcific aortic valve stenosis and colonies of progressively mineralized nanobacteria in the fibrocalcific nodules of the aortic cusps, as revealed by transmission electron microscopy. Consistent with their outstanding bioadhesivity, nanobacteria might serve as causative agents in the development of calcific aortic valve stenosis. PMID:17315391

  7. Endovascular repair of thoracic aortic aneurysms.

    PubMed

    Cartes-Zumelzu, F; Lammer, J; Kretschmer, G; Hoelzenbein, T; Grabenwöger, M; Thurnher, S

    2000-03-01

    The standard technique for the treatment of descending thoracic aortic aneurysms is elective open surgical repair with graft interposition. This standard approach, although steadily improving, is associated with high morbidity and substantial mortality rates and implies a major surgical procedure with lateral thoracotomy, use of cardiopulmonary bypass, long operation times and a variety of peri- and postoperative complications. This and the success of the first endoluminal treatment of abdominal aortic aneurysms by Parodi et al. prompted the attention to be thrown on the treatment of descending thoracic aortic aneurysms with endoluminal stent-grafts in many large centres. The aim of this new minimally invasive technique is to exclude the aneurysm from blood flow and in consequence to avoid pressure stress on the aneurysmatic aortic wall, by avoiding a large open operation with significant perioperative morbidity. The potentially beneficial effect of this new treatment approach was evaluated in the course of this study. PMID:10875224

  8. Anaesthetic management of aortic coarctation in pregnancy.

    PubMed

    Walker, E; Malins, A F

    2004-10-01

    We report two cases of aortic coarctation in pregnancy. The first was a 20-year-old nulliparous woman who underwent an aortic coarctation repair when she was 23 weeks old and subsequently developed an aneurysm at the site of initial repair. The second was a 20-year-old nulliparous woman with a severe uncorrected congenital aortic coarctation and upper body hypertension, who became pregnant whilst awaiting transcatheter dilatation of the coarctation. Antenatal care involved a multidisciplinary approach with obstetric, anaesthetic and cardiology input. Both parturients were delivered by elective caesarean section. A cautious, incremental regional anaesthetic technique was used, with no associated maternal or neonatal morbidity. Perioperative management focused on minimising haemodynamic disturbances. The management is discussed, together with the potential maternal and fetal complications of aortic coarctation in pregnancy. PMID:15477059

  9. Understanding the pathogenesis of abdominal aortic aneurysms

    PubMed Central

    Kuivaniemi, Helena; Ryer, Evan J.; Elmore, James R.; Tromp, Gerard

    2016-01-01

    Summary An aortic aneurysm is a dilatation in which the aortic diameter is ≥ 3.0 cm. If left untreated, the aortic wall continues to weaken and becomes unable to withstand the forces of the luminal blood pressure resulting in progressive dilatation and rupture, a catastrophic event associated with a mortality of 50 – 80%. Smoking and positive family history are important risk factors for the development of abdominal aortic aneurysms (AAA). Several genetic risk factors have also been identified. On the histological level, visible hallmarks of AAA pathogenesis include inflammation, smooth muscle cell apoptosis, extracellular matrix degradation, and oxidative stress. We expect that large genetic, genomic, epigenetic, proteomic and metabolomic studies will be undertaken by international consortia to identify additional risk factors and biomarkers, and to enhance our understanding of the pathobiology of AAA. Collaboration between different research groups will be important in overcoming the challenges to develop pharmacological treatments for AAA. PMID:26308600

  10. 48 CFR 252.204-7001 - Commercial and Government Entity (CAGE) code reporting.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Entity (CAGE) code reporting. 252.204-7001 Section 252.204-7001 Federal Acquisition Regulations System... (CAGE) code reporting. As prescribed in 204.7207, use the following provision: Commercial and Government Entity (CAGE) Code Reporting (AUG 1999) (a) The offeror is requested to enter its CAGE code on its...

  11. 30 CFR 56.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Skips and cages in same compartment. 56.19072... Hoisting Hoisting Procedures § 56.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  12. 48 CFR 252.204-7001 - Commercial and Government Entity (CAGE) code reporting.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Entity (CAGE) code reporting. 252.204-7001 Section 252.204-7001 Federal Acquisition Regulations System... (CAGE) code reporting. As prescribed in 204.7207, use the following provision: Commercial and Government Entity (CAGE) Code Reporting (AUG 1999) (a) The offeror is requested to enter its CAGE code on its...

  13. 30 CFR 56.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Skips and cages in same compartment. 56.19072... Hoisting Hoisting Procedures § 56.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  14. 48 CFR 252.204-7001 - Commercial and Government Entity (CAGE) code reporting.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Entity (CAGE) code reporting. 252.204-7001 Section 252.204-7001 Federal Acquisition Regulations System... (CAGE) code reporting. As prescribed in 204.7207, use the following provision: Commercial and Government Entity (CAGE) Code Reporting (AUG 1999) (a) The offeror is requested to enter its CAGE code on its...

  15. 30 CFR 56.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Skips and cages in same compartment. 56.19072... Hoisting Hoisting Procedures § 56.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  16. 48 CFR 252.204-7001 - Commercial and Government Entity (CAGE) code reporting.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Entity (CAGE) code reporting. 252.204-7001 Section 252.204-7001 Federal Acquisition Regulations System... (CAGE) code reporting. As prescribed in 204.7207, use the following provision: Commercial and Government Entity (CAGE) Code Reporting (AUG 1999) (a) The offeror is requested to enter its CAGE code on its...

  17. 30 CFR 57.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Skips and cages in same compartment. 57.19072... Hoisting Hoisting Procedures § 57.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  18. 48 CFR 252.204-7001 - Commercial and Government Entity (CAGE) code reporting.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Entity (CAGE) code reporting. 252.204-7001 Section 252.204-7001 Federal Acquisition Regulations System... (CAGE) code reporting. As prescribed in 204.7207, use the following provision: Commercial and Government Entity (CAGE) Code Reporting (AUG 1999) (a) The offeror is requested to enter its CAGE code on its...

  19. 30 CFR 57.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Skips and cages in same compartment. 57.19072... Hoisting Hoisting Procedures § 57.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  20. 30 CFR 57.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Skips and cages in same compartment. 57.19072... Hoisting Hoisting Procedures § 57.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  1. 30 CFR 56.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Skips and cages in same compartment. 56.19072... Hoisting Hoisting Procedures § 56.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  2. 30 CFR 57.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Skips and cages in same compartment. 57.19072... Hoisting Hoisting Procedures § 57.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  3. 30 CFR 57.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Skips and cages in same compartment. 57.19072... Hoisting Hoisting Procedures § 57.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  4. 30 CFR 56.19072 - Skips and cages in same compartment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Skips and cages in same compartment. 56.19072... Hoisting Hoisting Procedures § 56.19072 Skips and cages in same compartment. When combinations of cages and skips are used in the same compartment, the cages shall be enclosed to protect personnel from...

  5. Improved mouse cage provides versatility and ease in handling laboratory mice

    NASA Technical Reports Server (NTRS)

    Jones, N. D.

    1969-01-01

    Mouse cage system provides versatility and ease in handling laboratory mice, cleaning their cages, and collecting uncontaminated metabolic test specimens. The cage, compact and free standing, contains a screened bottom and funnel channel to collect waste. The feed is in the cage top and thereby separates the food and waste.

  6. 4. VIEW OF WATER TOWER FROM ELECTRICAL TRANSFORMER CAGE AT ...

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

    4. VIEW OF WATER TOWER FROM ELECTRICAL TRANSFORMER CAGE AT NORTH END OF SECOND FLOOR WAREHOUSE. VIEW TO WEST-NORTHWEST. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  7. 30. LOCKER CAGE, CHANGE AREA, TOILETS ABOVE ROOF PANEL STORAGE ...

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

    30. LOCKER CAGE, CHANGE AREA, TOILETS ABOVE ROOF PANEL STORAGE AREA. VIEW TO SOUTH. - Ford Motor Company Long Beach Assembly Plant, Assembly Building, 700 Henry Ford Avenue, Long Beach, Los Angeles County, CA

  8. 18. DETAIL OF SHAFT COLLAR AND CAGE GUIDES. VIEW LOOKING ...

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

    18. DETAIL OF SHAFT COLLAR AND CAGE GUIDES. VIEW LOOKING SOUTH INCLUDES DETAIL OF RIVETED STEEL CONSTRUCTION OF HEADFRAME. - Butte Mineyards, Stewart Mine, Intersection of Main & Woolman Streets, Butte, Silver Bow County, MT

  9. 6. VIEW OF UTILITY TUNNEL, DRYDOCK NO., 4 (CAGE ENCLOSES ...

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

    6. VIEW OF UTILITY TUNNEL, DRYDOCK NO., 4 (CAGE ENCLOSES ACCESS TO SEWAGE PIT) - U.S. Naval Base, Pearl Harbor, Dry Dock No. 4, West of State Route 92, West of Nimitz Gate, Pearl City, Honolulu County, HI

  10. Dodecaamide cages: organic 12-arm building blocks for supramolecular chemistry.

    PubMed

    Culshaw, Jamie L; Cheng, Ge; Schmidtmann, Marc; Hasell, Tom; Liu, Ming; Adams, Dave J; Cooper, Andrew I

    2013-07-10

    A simple, one-step amidation reaction is used to produce a range of 12-arm organic building blocks for supramolecular chemistry via the derivatization of porous imine cages. As an example, microporous dendrimers are prepared. PMID:23786167

  11. A pseudo-icosahedral cage {Gd12} based on aminomethylphosphonate.

    PubMed

    Zhang, Ze-Min; Zangana, Karzan H; Kostopoulos, Andreas K; Tong, Ming-Liang; Winpenny, Richard E P

    2016-05-31

    Reaction of (aminomethyl)phosphonic acid (ampH2) with a mixture of gadolinium and cobalt pivalates under solvothermal conditions, led to a pseudo-icosahedral cage {Gd12}, which shows a large magnetocaloric effect (MCE). PMID:27188600

  12. Laparoscopic extraperitoneal para-aortic lymphadenectomy

    PubMed Central

    Iserte, Pablo Padilla; Minig, Lucas; Zorrero, Cristina

    2015-01-01

    Lymph nodes are the main pathway in the spread of gynaecological malignancies, being a well-known prognostic factor. Lymph node dissection is a complex surgical procedure and requires surgical expertise to perform the procedure, thereby minimising complications. In addition, lymphadenectomy has value in the diagnosis, prognosis, and treatment of patients with gynaecologic cancer. Therefore, a video focused on the para-aortic retroperitoneal anatomy and the surgical technique of the extraperitoneal para-aortic lymphadenectomy is presented. PMID:26435746

  13. Peripartum presentation of an acute aortic dissection.

    PubMed

    Lewis, S; Ryder, I; Lovell, A T

    2005-04-01

    We report the case of an acute type A aortic dissection occurring in a 35-year-old parturient. The initial diagnosis was missed; a subsequent emergency Caesarean section 3 weeks after presentation was followed by the development of left ventricular failure and pulmonary oedema in the early postoperative period. Echocardiography confirmed the diagnosis of aortic dissection and the patient underwent a successful surgical repair. PMID:15640303

  14. Regional aortic distensibility and its relationship with age and aortic stenosis: a computed tomography study.

    PubMed

    Wong, Dennis T L; Narayan, Om; Leong, Darryl P; Bertaso, Angela G; Maia, Murilo G; Ko, Brian S H; Baillie, Timothy; Seneviratne, Sujith K; Worthley, Matthew I; Meredith, Ian T; Cameron, James D

    2015-06-01

    Aortic distensibility (AD) decreases with age and increased aortic stiffness is independently associated with adverse cardiovascular outcomes. The association of severe aortic stenosis (AS) with AD in different aortic regions has not been evaluated. Elderly subjects with severe AS and a cohort of patients without AS of similar age were studied. Proximal aortic cross-sectional-area changes during the cardiac cycle were determined using retrospective-ECG-gating on 128-detector row computed-tomography. Using oscillometric-brachial-blood-pressure measurements, the AD at the ascending-aorta (AA), proximal-descending-aorta (PDA) and distal-descending-aorta (DDA) was determined. Linear mixed effects modelling was used to determine the association of age and aortic stenosis on regional AD. 102 patients were evaluated: 36 AS patients (70-85 years), 24 AS patients (>85 years) and 42 patients without AS (9 patients <50 years, 20 patients between 51-70 years and 13 patients 70-85 years). When comparing patients 70-85 years, AA distensibility was significantly lower in those with AS compared to those without AS (0.9 ± 0.9 vs. 1.4 ± 1.1, P = 0.03) while there was no difference in the PDA (1.0 ± 1.1 vs. 1.0 ± 1.2, P = 0.26) and DDA (1.1 ± 1.2 vs. 1.2 ± 0.8, P = 0.97). In patients without AS, AD decreased with age in all aortic regions (P < 0.001). The AA in patients <50 years were the most distensible compared to other aortic regions. There is regional variation in aortic distensibility with aging. Patients with aortic stenosis demonstrated regional differences in aortic distensibility with lower distensibility demonstrated in the proximal ascending aorta compared to an age-matched cohort. PMID:25855464

  15. Linear diffusion into a Faraday cage.

    SciTech Connect

    Warne, Larry Kevin; Lin, Yau Tang; Merewether, Kimball O.; Chen, Kenneth C.

    2011-11-01

    Linear lightning diffusion into a Faraday cage is studied. An early-time integral valid for large ratios of enclosure size to enclosure thickness and small relative permeability ({mu}/{mu}{sub 0} {le} 10) is used for this study. Existing solutions for nearby lightning impulse responses of electrically thick-wall enclosures are refined and extended to calculate the nearby lightning magnetic field (H) and time-derivative magnetic field (HDOT) inside enclosures of varying thickness caused by a decaying exponential excitation. For a direct strike scenario, the early-time integral for a worst-case line source outside the enclosure caused by an impulse is simplified and numerically integrated to give the interior H and HDOT at the location closest to the source as well as a function of distance from the source. H and HDOT enclosure response functions for decaying exponentials are considered for an enclosure wall of any thickness. Simple formulas are derived to provide a description of enclosure interior H and HDOT as well. Direct strike voltage and current bounds for a single-turn optimally-coupled loop for all three waveforms are also given.

  16. Opportunity Studies Bait in Shark's Cage

    NASA Technical Reports Server (NTRS)

    2004-01-01

    In its 49th sol on Mars, NASA's Opportunity had nearly concluded its scientific examination of the extreme southwestern end of the outcrop in Meridiani Planum. In the 'Shark's Cage' area of the neighborhood called 'Shoemaker's Patio,' featured in this image from the front hazard avoidance camera, Opportunity deployed its arm to study the features called 'Shark's Tooth,' 'Shark Pellets,' and 'Lamination.' 'Shark's Tooth' is a piece of the unusual red rind that appears to fill cracks in the outcrop. This rind may be some kind of chemical alteration of the rocks. 'Shark Pellets' is an area of soil that was under investigation as part of the crater soil survey. 'Lamination' is a target with very thin layers that resemble uniform pages in a book, an indication of how the sediments were deposited. A final experiment in this area will be attempted on sol 51. Opportunity's front left wheel will 'scuff' the rock called 'Carousel.' 'Scuffing' involves scraping the rock with one wheel while holding all the others still. This experiment essentially turns the rover wheels into tools, to try and determine the hardness of the target rock.

  17. Aortic Dissection Type A in Alpine Skiers

    PubMed Central

    Schachner, Thomas; Fischler, Nikolaus; Dumfarth, Julia; Bonaros, Nikolaos; Krapf, Christoph; Schobersberger, Wolfgang; Grimm, Michael

    2013-01-01

    Patients and Methods. 140 patients with aortic dissection type A were admitted for cardiac surgery. Seventy-seven patients experienced their dissection in the winter season (from November to April). We analyzed cases of ascending aortic dissection associated with alpine skiing. Results. In 17 patients we found skiing-related aortic dissections. Skiers were taller (180 (172–200) cm versus 175 (157–191) cm, P = 0.008) and heavier (90 (68–125) kg versus 80 (45–110) kg, P = 0.002) than nonskiers. An extension of aortic dissection into the aortic arch, the descending thoracic aorta, and the abdominal aorta was found in 91%, 74%, and 69%, respectively, with no significant difference between skiers and nonskiers. Skiers experienced RCA ostium dissection requiring CABG in 17.6% while this was true for 5% of nonskiers (P = 0.086). Hospital mortality of skiers was 6% versus 13% in nonskiers (P = 0.399). The skiers live at an altitude of 170 (0–853) m.a.s.l. and experience their dissection at 1602 (1185–3105; P < 0.001) m.a.s.l. In 82% symptom start was during recreational skiing without any trauma. Conclusion. Skiing associated aortic dissection type A is usually nontraumatic. The persons affected live at low altitudes and practice an outdoor sport at unusual high altitude at cold temperatures. Postoperative outcome is good. PMID:23971024

  18. Electrostatic assembly of binary nanoparticle superlattices using protein cages

    NASA Astrophysics Data System (ADS)

    Kostiainen, Mauri A.; Hiekkataipale, Panu; Laiho, Ari; Lemieux, Vincent; Seitsonen, Jani; Ruokolainen, Janne; Ceci, Pierpaolo

    2013-01-01

    Binary nanoparticle superlattices are periodic nanostructures with lattice constants much shorter than the wavelength of light and could be used to prepare multifunctional metamaterials. Such superlattices are typically made from synthetic nanoparticles, and although biohybrid structures have been developed, incorporating biological building blocks into binary nanoparticle superlattices remains challenging. Protein-based nanocages provide a complex yet monodisperse and geometrically well-defined hollow cage that can be used to encapsulate different materials. Such protein cages have been used to program the self-assembly of encapsulated materials to form free-standing crystals and superlattices at interfaces or in solution. Here, we show that electrostatically patchy protein cages--cowpea chlorotic mottle virus and ferritin cages--can be used to direct the self-assembly of three-dimensional binary superlattices. The negatively charged cages can encapsulate RNA or superparamagnetic iron oxide nanoparticles, and the superlattices are formed through tunable electrostatic interactions with positively charged gold nanoparticles. Gold nanoparticles and viruses form an AB8fcc crystal structure that is not isostructural with any known atomic or molecular crystal structure and has previously been observed only with large colloidal polymer particles. Gold nanoparticles and empty or nanoparticle-loaded ferritin cages form an interpenetrating simple cubic AB structure (isostructural with CsCl). We also show that these magnetic assemblies provide contrast enhancement in magnetic resonance imaging.

  19. Homogenized boundary conditions and resonance effects in Faraday cages

    PubMed Central

    Hewitt, I. J.

    2016-01-01

    We present a mathematical study of two-dimensional electrostatic and electromagnetic shielding by a cage of conducting wires (the so-called ‘Faraday cage effect’). Taking the limit as the number of wires in the cage tends to infinity, we use the asymptotic method of multiple scales to derive continuum models for the shielding, involving homogenized boundary conditions on an effective cage boundary. We show how the resulting models depend on key cage parameters such as the size and shape of the wires, and, in the electromagnetic case, on the frequency and polarization of the incident field. In the electromagnetic case, there are resonance effects, whereby at frequencies close to the natural frequencies of the equivalent solid shell, the presence of the cage actually amplifies the incident field, rather than shielding it. By appropriately modifying the continuum model, we calculate the modified resonant frequencies, and their associated peak amplitudes. We discuss applications to radiation containment in microwave ovens and acoustic scattering by perforated shells. PMID:27279775

  20. Caged Protein Prenyltransferase Substrates: Tools for Understanding Protein Prenylation

    SciTech Connect

    DeGraw, Amanda J.; Hast, Michael A.; Xu, Juhua; Mullen, Daniel; Beese, Lorena S.; Barany, George; Distefano, Mark D.

    2010-11-15

    Originally designed to block the prenylation of oncogenic Ras, inhibitors of protein farnesyltransferase currently in preclinical and clinical trials are showing efficacy in cancers with normal Ras. Blocking protein prenylation has also shown promise in the treatment of malaria, Chagas disease and progeria syndrome. A better understanding of the mechanism, targets and in vivo consequences of protein prenylation are needed to elucidate the mode of action of current PFTase (Protein Farnesyltransferase) inhibitors and to create more potent and selective compounds. Caged enzyme substrates are useful tools for understanding enzyme mechanism and biological function. Reported here is the synthesis and characterization of caged substrates of PFTase. The caged isoprenoid diphosphates are poor substrates prior to photolysis. The caged CAAX peptide is a true catalytically caged substrate of PFTase in that it is to not a substrate, yet is able to bind to the enzyme as established by inhibition studies and X-ray crystallography. Irradiation of the caged molecules with 350 nm light readily releases their cognate substrate and their photolysis products are benign. These properties highlight the utility of those analogs towards a variety of in vitro and in vivo applications.

  1. General Considerations of Ruptured Abdominal Aortic Aneurysm: Ruptured Abdominal Aortic Aneurysm

    PubMed Central

    Lee, Chung Won; Bae, Miju; Chung, Sung Woon

    2015-01-01

    Although development of surgical technique and critical care, ruptured abdominal aortic aneurysm still carries a high mortality. In order to obtain good results, various efforts have been attempted. This paper reviews initial management of ruptured abdominal aortic aneurysm and discuss the key point open surgical repair and endovascular aneurysm repair. PMID:25705591

  2. TiN thin film deposition by cathodic cage discharge: effect of cage configuration and active species

    NASA Astrophysics Data System (ADS)

    de Freitas Daudt, N.; Pereira Barbosa, J. C.; Cavalcante Braz, D.; Barbalho Pereira, M.; Alves Junior, C.

    2012-12-01

    Plasma cathodic cage technique was developed recently in order to eliminate phenomena such as edge effects and overheating, which occur during conventional nitriding processes. In this work, the effect of plasma active species and cage configurations during thin film deposition of TiN were studied. This compound was chosen because its properties are very sensitive to slight variations in chemical composition and film thickness, becoming a good monitoring tool in fabrication process control. In order to verify the effect of cage geometry on the discharge and characteristics of the grown film, a cage made of titanium was used with different numbers and distribution of holes. Furthermore, different amounts of hydrogen were added to the Ar + N2 plasma atmosphere. Flow rates of Ar and N2 gas were fixed at 4 and 3 sccm, respectively and flow rates of H2 gas was 0, 1 and 2 sccm. Plasma species, electrical discharge and physical characteristics of the grown film were analyzed by Optical Emission Spectroscopy (OES), Atomic Force Microscopy (AFM), X-Ray Diffraction. It was observed by OES that the luminous intensity associated to Hα species is not proportional to flow rate of H2 gas. Electrical efficiency of the system, crystal structure and topography of the TiN film are strongly influenced by this behavior. For constant flow rate of H2 gas, it was found that with more holes at the top of the cage, deposition rate, crystallinity and roughness are higher, if compared to cages with a small number of holes at the top of cage. On the other hand, the opposite behavior was observed when more holes were located at the sidewall of cage.

  3. Evaluation of individually ventilated cage systems for laboratory rodents: cage environment and animal health aspects.

    PubMed

    Höglund, A U; Renström, A

    2001-01-01

    The use of individually ventilated cage (IVC) systems has become an attractive housing regime of laboratory rodents. The benefits of IVC systems are, reportedly, a high degree of containment combined with relative ease of handling, and a high degree of protection from allergenes. In the present study we tested whether two IVC systems (BioZone VentiRack, IVC1 and Techniplast SealSafe, IVC2S), in which we held mature male NMRI mice, were constructed to maintain a constant differential pressure, positive or negative, during a prolonged period of time. We also measured ammonia (NH3) concentrations after about 2 weeks of use, and CO2 build-up during a 60 min simulated power failure situation. In addition, animal weight development and bite-wound frequency were recorded (Renström et al. 2000). From the present study it is concluded that the IVC1 air handling system provides a more uniform and balanced differential pressure than the IVC2S. Both systems effectively scavenge NH3 when bedding material is not soaked by urine. Although the IVCs are dependent on the continual function of the fans to work properly, it seems unlikely that CO2 concentrations increase to hazardous levels, as a result of a one hour power failure, with the type of cages used in this study. Differences in weight development and bite-wound occurrence were noted between the two IVC systems. Causes for these differences could not be established and need more investigation. PMID:11201288

  4. Hemolytic anemia with aortic stenosis resolved by urgent aortic valve replacement.

    PubMed

    Kawase, Isamu; Matsuo, Tatsuro; Sasayama, Koji; Suzuki, Hiroyuki; Nishikawa, Hideo

    2008-08-01

    A 78-year-old man with aortic stenosis complained of dark colored urine followed by recurrent chest pain and syncopal episodes. Echocardiography showed severely calcified aortic stenosis with the maximal pressure gradient of 125 mm Hg. Hemoglobin was 7.9 g/dL, lactate dehydrogenase was 2,295 IU/L, haptoglobin was less than 10 mg/dL, reticulocyte count was elevated, and Coombs' test was negative. We performed an urgent aortic valve replacement. After the surgery, the patient's urine became clear and his chest pain and syncope abated. All laboratory data returned to normal physiological values. In conclusion, the observed hemolysis was related to the aortic shear stress of a calcified aortic valve. PMID:18640351

  5. New frontiers in aortic therapy: focus on current trials and devices in transcatheter aortic valve replacement.

    PubMed

    Gutsche, Jacob T; Patel, Prakash A; Walsh, Elizabeth K; Sophocles, Aris; Chern, Sy-Yeu S; Jones, David B; Anwaruddin, Saif; Desai, Nimesh D; Weiss, Stuart J; Augoustides, John G T

    2015-04-01

    The first decade of clinical experience with transcatheter aortic valve replacement since 2002 saw the development of 2 main valve systems, namely the Edwards Sapien balloon-expandable valve series and the Medtronic self-expanding CoreValve. These 2 valve platforms now have achieved commercial approval and application worldwide in patients with severe aortic stenosis whose perioperative risk for surgical intervention is high or extreme. In the second decade of transcatheter aortic valve replacement, clinical experience and refinements in valve design have resulted in clinical drift towards lower patient risk cohorts. There are currently 2 major trials, PARTNER II and SURTAVI, that are both evaluating the role of transcatheter aortic valve replacement in intermediate-risk patient cohorts. The results from these landmark trials may usher in a new clinical paradigm for transcatheter aortic valve replacement in its second decade. PMID:25572322

  6. Aortic Disease Presentation and Outcome Associated with ACTA2 mutations

    PubMed Central

    Regalado, Ellen S.; Guo, Dongchuan; Prakash, Siddharth; Bensend, Tracy A.; Flynn, Kelly; Estrera, Anthony; Safi, Hazim; Liang, David; Hyland, James; Child, Anne; Arno, Gavin; Boileau, Catherine; Jondeau, Guillaume; Braverman, Alan; Moran, Rocio; Morisaki, Takayuki; Morisaki, Hiroko; Consortium, Montalcino Aortic; Pyeritz, Reed; Coselli, Joseph; LeMaire, Scott; Milewicz, Dianna M.

    2015-01-01

    Background ACTA2 mutations are the major cause of familial thoracic aortic aneurysms and dissections. We sought to characterize these aortic diseases in a large case series of individuals with ACTA2 mutations. Methods and Results Aortic disease, management, and outcome associated with the first aortic event (aortic dissection or aneurysm repair) were abstracted from the medical records of 277 individuals with 41 various ACTA2 mutations. Aortic events occurred in 48% of these individuals, with the vast majority presenting with thoracic aortic dissections (88%) associated with 25% mortality. Type A dissections were more common than type B dissections (54% versus 21%), but the median age of onset of type B dissections was significantly younger than type A dissections (27 years, IQR 18–41 versus 36 years, IQR 26–45). Only 12% of aortic events were repair of ascending aortic aneurysms, which variably involved the aortic root, ascending aorta and aortic arch. Overall cumulative risk of an aortic event at age 85 years was 0.76 (95% CI 0.64, 0.86). After adjustment for intra-familial correlation, gender and race, mutations disrupting p.R179 and p.R258 were associated with significantly increased risk for aortic events, whereas p.R185Q and p.R118Q mutations showed significantly lower risk of aortic events compared to other mutations. Conclusions ACTA2 mutations are associated with high risk of presentation with an acute aortic dissection. The lifetime risk for an aortic event is only 76%, suggesting that additional environmental or genetic factors play a role in expression of aortic disease in individuals with ACTA2 mutations. PMID:25759435

  7. 14C-age tracers in global ocean circulation models

    NASA Astrophysics Data System (ADS)

    Koeve, W.; Wagner, H.; Kähler, P.; Oschlies, A.

    2015-07-01

    The natural abundance of 14C in total CO2 dissolved in seawater (DIC) is a property applied to evaluate the water age structure and circulation in the ocean and in ocean models. In this study we use three different representations of the global ocean circulation augmented with a suite of idealised tracers to study the potential and limitations of using natural 14C to determine water age, which is the time elapsed since a body of water has been in contact with the atmosphere. We find that, globally, bulk 14C-age is dominated by two equally important components, one associated with ageing, i.e. the time component of circulation, and one associated with a "preformed 14C-age". The latter quantity exists because of the slow and incomplete atmosphere-ocean equilibration of 14C particularly in high latitudes where many water masses form. In the ocean's interior, preformed 14C-age behaves like a passive tracer. The relative contribution of the preformed component to bulk 14C-age varies regionally within a given model, but also between models. Regional variability in the Atlantic Ocean is associated with the mixing of waters with very different end members of preformed 14C-age. Here, variations in the preformed component over space and time mask the circulation component to an extent that its patterns are not detectable from bulk 14C-age. Between models, the variability of preformed 14C-age can also be considerable (factor of 2), related to the combination of physical model parameters, which influence circulation dynamics or gas exchange. The preformed component was found to be very sensitive to gas exchange and moderately sensitive to ice cover. In our model evaluation, the choice of the gas-exchange constant from within the currently accepted range of uncertainty had such a strong influence on preformed and bulk 14C-age that if model evaluation would be based on bulk 14C-age, it could easily impair the evaluation and tuning of a model's circulation on global and regional

  8. Proteomic study of the microdissected aortic media in human thoracic aortic aneurysms.

    PubMed

    Serhatli, Muge; Baysal, Kemal; Acilan, Ceyda; Tuncer, Eylem; Bekpinar, Seldag; Baykal, Ahmet Tarik

    2014-11-01

    Aortic aneurysm is a complex multifactorial disease, and its molecular mechanism is not understood. In thoracic aortic aneurysm (TAA), the expansion of the aortic wall is lead by extracellular matrix (ECM) degeneration in the medial layer, which leads to weakening of the aortic wall. This dilatation may end in rupture and-if untreated-death. The aortic media is composed of vascular smooth muscle cells (VSMCs) and proteins involved in aortic elasticity and distensibility. Delineating their functional and quantitative decrease is critical in elucidating the disease causing mechanisms as well as the development of new preventive therapies. Laser microdissection (LMD) is an advanced technology that enables the isolation of the desired portion of tissue or cells for proteomics analysis, while preserving their integrity. In our study, the aortic media layers of 36 TAA patients and 8 controls were dissected using LMD technology. The proteins isolated from these tissue samples were subjected to comparative proteomic analysis by nano-LC-MS/MS, which enabled the identification of 352 proteins in aortic media. Among these, 41 proteins were differentially expressed in the TAA group with respect to control group, and all were downregulated in the patients. Of these medial proteins, 25 are novel, and their association with TAA is reported for the first time in our study. Subsequent analysis of the data by ingenuity pathway analysis (IPA) shows that the majority of differentially expressed proteins were found to be cytoskeletal-associated proteins and components of the ECM which are critical in maintaining aortic integrity. Our results indicate that the protein expression profile in the aortic media from TAA patients differs significantly from controls. Further analysis of the mechanism points to markers of pathological ECM remodeling, which, in turn, affect VSMC cytosolic structure and architecture. In the future, the detailed investigation of the differentially expressed

  9. State-of-the-art aortic imaging: Part II - applications in transcatheter aortic valve replacement and endovascular aortic aneurysm repair.

    PubMed

    Rengier, Fabian; Geisbüsch, Philipp; Schoenhagen, Paul; Müller-Eschner, Matthias; Vosshenrich, Rolf; Karmonik, Christof; von Tengg-Kobligk, Hendrik; Partovi, Sasan

    2014-01-01

    Transcatheter aortic valve replacement (TAVR) as well as thoracic and abdominal endovascular aortic repair (TEVAR and EVAR) rely on accurate pre- and postprocedural imaging. This review article discusses the application of imaging, including preprocedural assessment and measurements as well as postprocedural imaging of complications. Furthermore, the exciting perspective of computational fluid dynamics (CFD) based on cross-sectional imaging is presented. TAVR is a minimally invasive alternative for treatment of aortic valve stenosis in patients with high age and multiple comorbidities who cannot undergo traditional open surgical repair. Given the lack of direct visualization during the procedure, pre- and peri-procedural imaging forms an essential part of the intervention. Computed tomography angiography (CTA) is the imaging modality of choice for preprocedural planning. Routine postprocedural follow-up is performed by echocardiography to confirm treatment success and detect complications. EVAR and TEVAR are minimally invasive alternatives to open surgical repair of aortic pathologies. CTA constitutes the preferred imaging modality for both preoperative planning and postoperative follow-up including detection of endoleaks. Magnetic resonance imaging is an excellent alternative to CT for postoperative follow-up, and is especially beneficial for younger patients given the lack of radiation. Ultrasound is applied in screening and postoperative follow-up of abdominal aortic aneurysms, but cross-sectional imaging is required once abnormalities are detected. Contrast-enhanced ultrasound may be as sensitive as CTA in detecting endoleaks. PMID:24429327

  10. Microgravity alters respiratory abdominal and rib cage motion during sleep

    PubMed Central

    Prisk, G. Kim; Paiva, Manuel

    2009-01-01

    The abdominal and rib cage contributions to tidal breathing differ between rapid-eye-movement (REM) and non-NREM sleep. We hypothesized that abdominal relative contribution during NREM and REM sleep would be altered in different directions when comparing sleep on Earth with sleep in sustained microgravity (μG), due to conformational changes and differences in coupling between the rib cage and the abdominal compartment induced by weightlessness. We studied respiration during sleep in five astronauts before, during, and after two Space Shuttle missions. A total of 77 full-night (8 h) polysomnographic studies were performed; abdominal and rib cage respiratory movements were recorded using respiratory inductive plethysmography. Breath-by-breath analysis of respiration was performed for each class: awake, light sleep, deep sleep, and REM sleep. Abdominal contribution to tidal breathing increased in μG, with the first measure in space being significantly higher than preflight values, followed by a return toward preflight values. This was observed for all classes. Preflight, rib cage, and abdominal movements were found to be in phase for all but REM sleep, for which an abdominal lead was observed. The abdominal leading role during REM sleep increased while deep sleep showed the opposite behavior, the rib cage taking a leading role in-flight. In μG, the percentage of inspiratory time in the overall breath, the duty cycle (TI/TTot), decreased for all classes considered when compared with preflight, while normalized inspiratory flow, taking the awake values as reference, increased in-flight for light sleep, deep sleep, and REM. Changes in abdominal-rib cage displacements probably result from a less efficient operating point for the diaphragm and a less efficient coupling between the abdomen and the apposed portion of the rib cage in μG. However, the preservation of total ventilation suggests that short-term adaptive mechanisms of ventilatory control compensate for these

  11. Talk to Your Doctor about Abdominal Aortic Aneurysm

    MedlinePlus

    ... español Talk to Your Doctor about Abdominal Aortic Aneurysm Browse Sections The Basics Overview What is AAA? ... doctor about getting screened (tested) for abdominal aortic aneurysm (AAA). If AAA isn't found and treated ...

  12. Genetics Home Reference: familial thoracic aortic aneurysm and dissection

    MedlinePlus

    ... Home Health Conditions familial TAAD familial thoracic aortic aneurysm and dissection Enable Javascript to view the expand/ ... Open All Close All Description Familial thoracic aortic aneurysm and dissection ( familial TAAD ) involves problems with the ...

  13. MicroRNAs, fibrotic remodeling, and aortic aneurysms.

    PubMed

    Milewicz, Dianna M

    2012-02-01

    Aortic aneurysms are a common clinical condition that can cause death due to aortic dissection or rupture. The association between aortic aneurysm pathogenesis and altered TGF-β signaling has been the subject of numerous investigations. Recently, a TGF-β-responsive microRNA (miR), miR-29, has been identified to play a role in cellular phenotypic modulation during aortic development and aging. In this issue of JCI, Maegdefessel and colleagues demonstrate that decreasing the levels of miR-29b in the aortic wall can attenuate aortic aneurysm progression in two different mouse models of abdominal aortic aneurysms. This study highlights the relevance of miR-29b in aortic disease but also raises questions about its specific role. PMID:22269322

  14. Phosphate release and force generation in cardiac myocytes investigated with caged phosphate and caged calcium.

    PubMed Central

    Araujo, A; Walker, J W

    1996-01-01

    The phosphate (P(i)) dissociation step of the cross-bridge cycle was investigated in skinned rat ventricular myocytes to examine its role in force generation and Ca(2+) regulation in cardiac muscle. Pulse photolysis of caged P(i) (alpha-carboxyl-2-nitrobenzyl phosphate) produced up to 3 mM P(i) within the filament lattice, resulting in an approximately exponential decline in steady-state tension. The apparent rate constant, k (rho i), increased linearly with total P(i) concentration (initial plus photoreleased), giving an apparent second-order rate constant for P(i) binding of 3100 M(-1) s(-1), which is intermediate in value between fast and slow skeletal muscles. A decrease in the level of Ca(2+) activation to 20% of maximum tension reduced k (rho i) by twofold and increased the relative amplitude by threefold, consistent with modulation of P(i) release by Ca2+. A three-state model, with separate but coupled transitions for force generation and P(i) dissociation, and a Ca(2+)-sensitive forward rate constant for force generation, was compatible with the data. There was no evidence for a slow phase of tension decline observed previously in fast skeletal fibers at low Ca(2+), suggesting differences in cooperative mechanisms in cardiac and skeletal muscle. In separate experiments, tension development was initiated from a relaxed state by photolysis of caged Ca(2+). The apparent rate constant, k(Ca), was accelerated in the presence of high P(i) consistent with close coupling between force generation and P(i) dissociation, even when force development was initiated from a relaxed state. k(Ca) was also dependent on the level of Ca(2+) activation. However, significant quantitative differences between k (rho i) and k(Ca), including different sensitivities to Ca(2+) and P(i) indicate that caged Ca(2+) tension transients are influenced by additional Ca(2+)-dependent but P i-independent steps that occur before P(i) release. Data from both types of measurements suggest that

  15. Real-time transesophageal echocardiography facilitates antegrade balloon aortic valvuloplasty

    PubMed Central

    Ito, Kazato; Yano, Kentaro; Tanaka, Chiharu; Nakashoji, Tomohiro; Tonomura, Daisuke; Takehara, Kosuke; Kino, Naoto; Yoshida, Masataka; Kurotobi, Toshiya; Tsuchida, Takao; Fukumoto, Hitoshi

    2016-01-01

    We report two cases of severe aortic stenosis (AS) where antegrade balloon aortic valvuloplasty (BAV) was performed under real-time transesophageal echocardiography (TEE) guidance. Real-time TEE can provide useful information for evaluating the aortic valve response to valvuloplasty during the procedure. It was led with the intentional wire-bias technique in order to compress the severely calcified leaflet, and consequently allowed the balloon to reach the largest possible size and achieve full expansion of the aortic annulus. PMID:27054107

  16. Thoracic Endovascular Stent Graft Repair of Middle Aortic Syndrome.

    PubMed

    Kim, Joung Taek; Lee, Mina; Kim, Young Sam; Yoon, Yong Han; Baek, Wan Ki

    2016-09-01

    Middle aortic syndrome is a rare disease defined as a segmental narrowing of the distal descending thoracic or abdominal aorta. A thoracoabdominal bypass or endovascular treatment is the choice of treatment. Endovascular therapy consists of a balloon dilatation and stent implantation. Recently, thoracic endovascular aortic repair has been widely used in a variety of aortic diseases. We report a case of middle aortic syndrome treated with a thoracic endovascular stent graft. PMID:27549552

  17. Syphilitic aortic aneurysm presenting with upper airway obstruction.

    PubMed

    Waikittipong, Somchai

    2012-10-01

    Syphilitic aortic aneurysms are uncommon today. A rare case of syphilitic aortic arch aneurysm with successful surgical treatment is reported. A 42-year-old man presented with upper airway obstruction. Chest radiography showed a superior mediastinal mass, and computed tomography revealed a large saccular aortic arch aneurysm that compressed the trachea. Dacron graft replacement of the aortic arch was successfully performed under circulatory arrest with antegrade cerebral perfusion. PMID:23087303

  18. Imaging of abdominal aortic aneurysms.

    PubMed

    Sparks, Amy R; Johnson, Philip L; Meyer, Mark C

    2002-04-15

    Given the high rate of morbidity and mortality associated with abdominal aortic aneurysms (AAAs), accurate diagnosis and preoperative evaluation are essential for improved patient outcomes. Ultrasonography is the standard method of screening and monitoring AAAs that have not ruptured. In the past, aortography was commonly used for preoperative planning in the repair of AAAs. More recently, computed tomography (CT) has largely replaced older, more invasive methods. Recent advances in CT imaging technology, such as helical CT and CT angiography, offer significant advantages over traditional CT. These methods allow for more rapid scans and can produce three-dimensional images of the AAA and important adjacent vascular structures. Use of endovascular stent grafts has increased recently and is less invasive for the repair of AAAs in selected cases. Aortography and CT angiography can precisely determine the size and surrounding anatomy of the AAA to identify appropriate candidates for the use of endovascular stent grafts. Helical CT and CT angiography represent an exciting future in the preoperative evaluation of AAAs. However, this technology is not the standard of care because of the lack of widespread availability, the cost associated with obtaining new equipment, and the lack of universal protocols necessary for acquisition and reconstruction of these images. PMID:11989632

  19. Rapid prototyping in aortic surgery.

    PubMed

    Bangeas, Petros; Voulalas, Grigorios; Ktenidis, Kiriakos

    2016-04-01

    3D printing provides the sequential addition of material layers and, thus, the opportunity to print parts and components made of different materials with variable mechanical and physical properties. It helps us create 3D anatomical models for the better planning of surgical procedures when needed, since it can reveal any complex anatomical feature. Images of abdominal aortic aneurysms received by computed tomographic angiography were converted into 3D images using a Google SketchUp free software and saved in stereolithography format. Using a 3D printer (Makerbot), a model made of polylactic acid material (thermoplastic filament) was printed. A 3D model of an abdominal aorta aneurysm was created in 138 min, while the model was a precise copy of the aorta visualized in the computed tomographic images. The total cost (including the initial cost of the printer) reached 1303.00 euros. 3D imaging and modelling using different materials can be very useful in cases when anatomical difficulties are recognized through the computed tomographic images and a tactile approach is demanded preoperatively. In this way, major complications during abdominal aorta aneurysm management can be predicted and prevented. Furthermore, the model can be used as a mould; the development of new, more biocompatible, less antigenic and individualized can become a challenge in the future. PMID:26803324

  20. Hybrid treatment of aortic arch disease

    PubMed Central

    Metzger, Patrick Bastos; Rossi, Fabio Henrique; Moreira, Samuel Martins; Issa, Mario; Izukawa, Nilo Mitsuru; Dinkhuysen, Jarbas J.; Spina Neto, Domingos; Kambara, Antônio Massamitsu

    2014-01-01

    Introduction The management of thoracic aortic disease involving the ascending aorta, aortic arch and descending thoracic aorta are technically challenging and is an area in constant development and innovation. Objective To analyze early and midterm results of hybrid treatment of arch aortic disease. Methods Retrospective study of procedures performed from January 2010 to December 2012. The end points were the technical success, therapeutic success, morbidity and mortality, neurologic outcomes, the rate of endoleaks and reinterventions. Results A total of 95 patients treated for thoracic aortic diseases in this period, 18 underwent hybrid treatment and entered in this study. The average ages were 62.3 years. The male was present in 66.7%. The technical and therapeutic success was 94.5% e 83.3%. The perioperative mortality rate of 11.1%. There is any death during one-year follow- up. The reoperation rates were 16.6% due 2 cases of endoleak Ia and one case of endoleak II. There is any occlusion of anatomic or extra anatomic bypass during follow up. Conclusion In our study, the hybrid treatment of aortic arch disease proved to be a feasible alternative of conventional surgery. The therapeutic success rates and re- interventions obtained demonstrate the necessity of thorough clinical follow-up of these patients in a long time. PMID:25714205

  1. Primary Stenting in Infrarenal Aortic Occlusive Disease

    SciTech Connect

    Nyman, Ulf; Uher, Petr; Lindh, Mats; Lindblad, Bengt; Ivancev, Krasnodar

    2000-03-15

    Purpose: To evaluate the results of primary stenting in aortic occlusive disease.Methods: Thirty patients underwent primary stenting of focal concentric (n = 2) and complex aortic stenoses (n = 19), and aortic or aorto-iliac occlusions (n = 9). Sixteen patients underwent endovascular outflow procedures, three of whom also had distal open surgical reconstructions. Median follow-up was 16 months (range 1-60 months).Results: Guidewire crossing of two aorto-biiliac occlusions failed, resulting in a 93% (28/30) technical success. Major complications included one access hematoma, one myocardial infarction, one death (recurrent thromboembolism) in a patient with widespread malignancy, and one fatal hemorrhage during thrombolysis of distal emboli from a recanalized occluded iliac artery. One patient did not improve his symptoms, resulting in a 1-month clinical success of 83% (25/30). Following restenting the 26 stented survivors changed their clinical limb status to +3 (n = 17) and +2 (n = 9). During follow-up one symptomatic aortic restenosis occurred and was successfully restented.Conclusions: Primary stenting of complex aortic stenoses and short occlusions is an attractive alternative to conventional surgery. Larger studies with longer follow-up and stratification of lesion morphology are warranted to define its role relative to balloon angioplasty. Stenting of aorto-biiliac occlusions is feasible but its role relative to bypass grafting remains to be defined.

  2. Advances in Transcatheter Aortic Valve Replacement

    PubMed Central

    Kleiman, Neal S.; Reardon, Michael J.

    2016-01-01

    Transcatheter aortic valve replacement (TAVR) is becoming widely used for the treatment of symptomatic severe aortic stenosis in patients with high surgical risk. Data from The PARTNER Trial (Placement of AoRtic TraNscathetER Valves) and the Medtronic CoreValve® U.S. Pivotal Investigational Device Exemption trial indicate that survival for extreme-risk patients is superior to best medical therapy and equivalent or superior to surgical aortic valve replacement (SAVR), although long-term durability remains unknown. Paravalvular leak remains higher in TAVR than SAVR, as does permanent pacemaker implantation in self-expanding valves. New-generation valves are addressing these issues, especially for paravalvular leak. There is strong evidence that TAVR is appropriate for both extreme-risk and high-risk patients with symptomatic severe aortic stenosis, and the continued development of new valves are making implantation more reliable. This review discusses the studies supporting the use of TAVR and explores current advances in the field. PMID:27127560

  3. Metabolic Cages for a Space Flight Model in the Rat

    NASA Technical Reports Server (NTRS)

    Harper, Jennifer S.; Mulenburg, Gerald M.; Evans, Juli; Navidi, Meena; Wolinsky, Ira; Arnaud, Sara B.

    1994-01-01

    A variety of space flight models are available to mimic the physiologic changes seen in the rat during weightlessness. The model reported by Wronski and Morey-Holton has been widely used by many investigators, in musculoskeletal physiologic studies especially, resulting in accumulation of an extensive database that enables scientists to mimic space flight effects in the 1-g environment of Earth. However, information on nutrition or gastrointestinal and renal function in this space flight model is limited by the difficulty in acquiring uncontaminated metabolic specimens for analysis. In the Holton system, a traction tape harness is applied to the tail, and the rat's hindquarters are elevated by attaching the harness to a pulley system. Weight-bearing hind limbs are unloaded, and there is a headward fluid shift. The tail-suspended rats are able to move freely about their cages on their forelimbs and tolerate this procedure with minimal signs of stress. The cage used in Holton's model is basically a clear acrylic box set on a plastic grid floor with the pulley and tail harness system attached to the open top of the cage. Food is available from a square food cup recessed into a corner of the floor. In this system, urine, feces, and spilled food fall through the grid floor onto absorbent paper beneath the cage and cannot be separated and recovered quantitatively for analysis in metabolic balance studies. Commercially available metabolic cages are generally cylindrical and have been used with a centrally located suspension apparatus in other space flight models. The large living area, three times as large as most metabolic cages, and the free range of motion unique to Holton's model, essential for musculoskeletal investigations, were sacrificed. Holton's cages can accommodate animals ranging in weight from 70 to 600 g. Although an alternative construction of Holton's cage has been reported, it does not permit collection of separate urine and fecal samples. We describe

  4. Endovascular repair of a type B aortic dissection with a right-sided aortic arch: case report

    PubMed Central

    2013-01-01

    Right-sided aortic arch is a rare anomaly, and aortic dissection involving a right-sided aortic arch is extremely rare. We report the case of a 65-year-old man with a right-sided aortic arch and a right descending aortic dissection and a stent-graft was accurately deployed without perioperative complications. There were no any complaints and complications after 18 months follow-up. The CTA demonstrated that the false lumen was largely thrombosed only with a mild type II endoleak and a mild descending aortic expansion. We feel that endovascular repair is feasible to patient of type B aortic dissection with a right-sided aortic arch. However, long-term clinical efficacy and safety have yet to be confirmed. PMID:23343010

  5. Diagnosis and management of acute aortic syndromes: dissection, intramural hematoma, and penetrating aortic ulcer.

    PubMed

    Bonaca, Marc P; O'Gara, Patrick T

    2014-01-01

    Acute aortic syndromes constitute a spectrum of conditions characterized by disruptions in the integrity of the aortic wall that may lead to potentially catastrophic outcomes. They include classic aortic dissection, intramural hematoma, and penetrating aortic ulcer. Although imaging studies are sensitive and specific, timely diagnosis can be delayed because of variability in presenting symptoms and the relatively low frequency with which acute aortic syndromes are seen in the emergency setting. Traditional classification systems, such as the Stanford system, facilitate early treatment decision-making through recognition of the high risk of death and major complications associated with involvement of the ascending aorta (type A). These patients are treated surgically unless intractable and severe co-morbidities are present. Outcomes with dissections that do not involve the ascending aorta (type B) depend on the presence of acute complications (e.g., malperfusion, early aneurysm formation, leakage), the patency and size of the false lumen, and patient co-morbidities. Patients with uncomplicated type B dissections are initially treated medically. Endovascular techniques have emerged as an alternative to surgery for the management of complicated type B dissections when intervention is necessary. Patients with acute aortic syndromes require aggressive medical care, risk stratification for additional complications and targeted genetic assessment as well as careful long-term monitoring to assess for evolving complications. The optimal care of patients with acute aortic syndrome requires the cooperation of members of an experienced multidisciplinary team both in the acute and chronic setting. PMID:25156302

  6. [Acute coronary artery dissection after aortic valve replacement].

    PubMed

    Machado, Fernando de Paula; Sampaio, Roney Orismar; Mazzucato, Fernanda Lopez; Tarasoutchi, Flávio; Spina, Guilherme Sobreira; Grinberg, Max

    2010-02-01

    Late aortic dissection can occur after aortic valve replacement surgery, but rarely in the first postoperative month. Coronary artery dissection is rare and usually occurs after coronary angiography. We report a rare case of coronary artery dissection followed by myocardial infarction in the immediate postoperative period of a successful aortic valve replacement with a good postoperative evolution. PMID:20428604

  7. A metabolic cage for the hindlimb suspended rat

    NASA Technical Reports Server (NTRS)

    Evans, J.; Mulenburg, G. M.; Harper, J. S.; Skundberg, T. L.; Navidi, M.; Arnaud, S. B.

    1994-01-01

    Hindlimb suspension has been successfully used to simulate the effects of microgravity in rats. The cage and suspension system developed by E. R. Holton is designed to produce a headward shift of fluid and unload the hindlimbs in rodents, causing changes in bone and muscle similar to those in animals and humans exposed to spaceflight. While the Holton suspension system simulates many of the conditions observed in the spaceflight animal, it does not provide for the collection of urine and feces needed to monitor some metabolic activities. As a result, only limited information has been gathered on the nutritional status, and the gastrointestinal and renal function of animals using that model. Although commercial metabolic cages are available, they are usually cylindrical and require a centrally located suspension system and thus, do not readily permit movement of the rats. The limited floor space of commercial cages may affect comparisons with studies using the Holton model which has more than twice the living space of most commercially available cages. To take advantage of the extra living space and extensive data base that has been developed with the Holton model, Holton's cage was modified to make urine and fecal collections possible.

  8. Role of Cages in Revision Arthroplasty of the Acetabulum.

    PubMed

    Mäkinen, Tatu J; Kuzyk, Paul; Safir, Oleg A; Backstein, David; Gross, Allan E

    2016-02-01

    ➤ The outcome of acetabular revision is heavily influenced by the degree of associated bone loss.➤ Uncemented hemispherical acetabular components can be used in the majority of acetabular revisions, although occasionally the degree of bone loss precludes the stability of the hemispherical component at the correct anatomic level or there is minimal bleeding host bone left for biologic fixation.➤ Massive acetabular bone loss resulting in the need for bone grafts or highly porous augments involving more than half of the acetabulum is one of the main indications for the use of cages.➤ The cup-cage reconstruction is based on bone-grafting the deficient acetabulum and securing a hemispherical, highly porous metal component with multiple screws to bridge the discontinuity and off-loading the hemispherical component with a titanium cage spanning from ischium to ilium.➤ In addition to managing pelvic discontinuities, the cup-cage construct can also be used in hips without discontinuity as the hemispherical, highly porous metal component is used to restore bone stock.➤ In situations in which there is not enough bleeding host bone to secure a hemispherical component, a highly porous metal augment can be used to address the osseous deficiency. The augment is also protected with a cage to assist bone ingrowth. PMID:26842414

  9. Accelerative forces associated with routine inhouse transportation of rodent cages.

    PubMed

    Hurst, Keriann; Litwak, Kenneth N

    2012-01-01

    Transportation of rodents has repeatedly been demonstrated to potentially affect research outcomes. In addition, rapid acceleration and deceleration have marked physiologic effects. The current study determined the accelerative forces associated with common types of animal transportation within the institution and means of reducing these effects. A rodent-sized (24 g) accelerometer was placed in a standard polycarbonate mouse cage, which then was hand-carried or loaded onto a plastic, small metal, or large metal cart. The cage then moved along a set path that included several flooring types and obstacles. Accelerative forces within the mouse cage varied by as much as 35 m/s(2) in as little as 1 s, primarily along the vertical axis (Z-axis). Measured acceleration was greatest with the plastic cart and lowest during hand-carrying. The placement of a towel under the cage dampened in-cage acceleration due to cart use by more than 50%, whereas a similarly located underpad had no significant effect. These data document that small rodents typically are exposed to considerable motion during transportation. The resulting physical and physiologic effects could affect study outcomes. PMID:23312081

  10. Echocardiographic detection of subvalvar aortic root aneurysm extending to mitral valve annulus as complication of aortic valve endocarditis.

    PubMed Central

    Griffiths, B E; Petch, M C; English, T A

    1982-01-01

    Acute aortic regurgitation as a consequence of infective endocarditis developed in a young man after peritonitis. A large subvalvar aortic root aneurysm extending to the mitral valve annulus together with features of severe acute aortic regurgitation were shown by M-mode echocardiography. The echocardiographic findings were confirmed at operation when obliteration of the aneurysmal space and aortic valve replacement were performed. Postoperative echocardiography confirmed obliteration of the aneurysmal space. Images PMID:6895998

  11. Multiple multilayer stents for thoracoabdominal aortic aneurysm: a possible new tool for aortic endovascular surgery

    PubMed Central

    Tolva, Valerio Stefano; Bianchi, Paolo Guy; Cireni, Lea Valeria; Lombardo, Alma; Keller, Guido Carlo; Parati, Gianfranco; Casana, Renato Maria

    2012-01-01

    Purpose Endovascular surgery data are confirming the paramount role of modern endovascular tools for a safe and sure exclusion of thoracoabdominal lesions. Case report A 57-year-old female presented with severe comorbidity affected by a 58 mm thoracoabdominal aortic aneurysm (TAAA). After patient-informed consent and local Ethical Committee and Italian Public Health Ministry authorization, three multilayer stents were implanted in the thoracoabdominal aortic tract, obtaining at a 20-month computed tomography scan follow up, a complete exclusion of the TAAA, with normal patency of visceral vessels. Conclusion Multilayer stents can be used in thoracoabdominal aortic aneurysm, with positive results. PMID:22866014

  12. Successful repair of aortic annulus rupture during transcatheter aortic valve replacement using extracorporeal membrane oxygenation support.

    PubMed

    Negi, Smita I; Patel, Jay; Patel, Manish; Loyalka, Pranav; Kar, Biswajit; Gregoric, Igor

    2015-09-01

    Aortic annular rupture is a rare and much dreaded complication of transcatheter aortic valve replacement. Device oversizing to prevent post-procedural paravalvular leak is the most commonly identified cause of this complication. However, mechanical stress in a heavily calcified non-compliant vessel can also lead to annular rupture in this older population. We describe a case of aortic annular rupture with involvement of right coronary artery ostium leading to cardiac tamponade and cardiac arrest, successfully managed by extracorporeal membrane oxygenation support, open drainage of the pericardial space, pericardial patching of the defect and bypass of the affected vessel with excellent post-procedural results. PMID:23990118

  13. Abdominal aortic aneurysmectomy in renal transplant patients.

    PubMed Central

    Lacombe, M

    1986-01-01

    Five patients who had undergone renal transplantation 3 months to 23 years ago were operated on successfully for an abdominal aortic aneurysm. In the first case, dating from 1973, the kidney was protected by general hypothermia. In the remaining patients, no measure was used to protect the kidney. Only one patient showed a moderate increase of blood creatinine in the postoperative period; renal function returned to normal in 15 days. All five patients have normal renal function 6 months to 11 years after aortic repair. Results obtained in this series show that protection of the transplant during aortic surgery is not necessary, provided adequate surgical technique is used. Such a technique is described in detail. Its use simplifies surgical treatment of such lesions and avoids the complex procedures employed in the seven previously published cases. Images FIGS. 1A and B. FIGS. 2A and B. FIGS. 3A and B. FIGS. 4A and B. FIGS. 5A and B. PMID:3510592

  14. Diagnosis and Management of Valvular Aortic Stenosis

    PubMed Central

    Czarny, Matthew J; Resar, Jon R

    2014-01-01

    Valvular aortic stenosis (AS) is a progressive disease that affects 2% of the population aged 65 years or older. The major cause of valvular AS in adults is calcification and fibrosis of a previously normal tricuspid valve or a congenital bicuspid valve, with rheumatic AS being rare in the United States. Once established, the rate of progression of valvular AS is quite variable and impossible to predict for any particular patient. Symptoms of AS are generally insidious at onset, though development of any of the three cardinal symptoms of angina, syncope, or heart failure portends a poor prognosis. Management of symptomatic AS remains primarily surgical, though transcatheter aortic valve replacement (TAVR) is becoming an accepted alternative to surgical aortic valve replacement (SAVR) for patients at high or prohibitive operative risk. PMID:25368539

  15. Mechanical versus biological aortic valve replacement strategies.

    PubMed

    Reineke, D; Gisler, F; Englberger, L; Carrel, T

    2016-04-01

    Aortic valve replacement (AVR) is the most frequently performed procedure in valve surgery. The controversy about the optimal choice of the prosthetic valve is as old as the technique itself. Currently there is no perfect valve substitute available. The main challenge is to choose between mechanical and biological prosthetic valves. Biological valves include pericardial (bovine, porcine or equine) and native porcine bioprostheses designed in stented, stentless and sutureless versions. Homografts and pulmonary autografts are reserved for special indications and will not be discussed in detail in this review. We will focus on the decision making between artificial biological and mechanical prostheses, respectively. The first part of this article reviews guideline recommendations concerning the choice of aortic prostheses in different clinical situations while the second part is focused on novel strategies in the treatment of patients with aortic valve pathology. PMID:26678683

  16. [Abdominal aortic aneurysm and renovascular disease].

    PubMed

    Riambau, Vicente; Guerrero, Francisco; Montañá, Xavier; Gilabert, Rosa

    2007-06-01

    Recent technological advances in the diagnosis and therapy of abdominal aortic aneurysm and renovascular disease are continuing to bring about changes in the way patients suffering from these conditions are treated. The prevalence of both these conditions is increasing. This is due to greater life-expectancy in patients with arteriosclerosis, a pathogenetic factor underlying both conditions. The application of diagnostic imaging techniques to non-vascular conditions has led to the early diagnosis of abdominal aortic aneurysm. Clinical suspicion of reno-vascular disease can be confirmed easily using high-resolution diagnostic imaging modalities such as CT angiography and magnetic resonance angiography. Endovascular intervention is successfully replacing conventional surgical repair techniques, with the result that it may be possible to improve outcome in both conditions using effective and minimally invasive approaches. Future technological developments will enable these endovascular techniques to be applied in the large majority of patients with abdominal aortic aneurysm or renovascular disease. PMID:17580053

  17. The Genetic Basis of Aortic Aneurysm

    PubMed Central

    Lindsay, Mark E.; Dietz, Harry C.

    2014-01-01

    Gene identification in human aortic aneurysm conditions is proceeding at a rapid pace and the integration of pathogenesis-based management strategies in clinical practice is an emerging reality. Human genetic alterations causing aneurysm involve diverse gene products including constituents of the extracellular matrix, cell surface receptors, intracellular signaling molecules, and elements of the contractile cytoskeleton. Animal modeling experiments and human genetic discoveries have extensively implicated the transforming growth factor-β (TGF-β) cytokine-signaling cascade in aneurysm progression, but mechanistic links between many gene products remain obscure. This chapter will integrate human genetic alterations associated with aortic aneurysm with current basic research findings in an attempt to form a reconciling if not unifying model for hereditary aortic aneurysm. PMID:25183854

  18. Acute Aortic Dissection Extending Into the Lung.

    PubMed

    Makdisi, George; Said, Sameh M; Schaff, Hartzell V

    2015-07-01

    The radiologic manifestations of ruptured acute aortic dissection, Stanford type A aortic dissection, DeBakey type 1 can present in different radiographic scenarios with devastating outcomes. Here, we present a rare case of a 70-year-old man who presented to the emergency department with chest pain radiating to the back. A chest computed tomography scan showed a Stanford type A, DeBakey type 1, acute aortic dissection ruptured into the aortopulmonary window and stenosing the pulmonary trunk, both main pulmonary arteries, and dissecting the bronchovascular sheaths and flow into the pulmonary interstitium, causing pulmonary interstitial hemorrhage. The patient underwent emergent ascending aorta replacement with hemiarch replacement with circulatory arrest. The postoperative course was unremarkable. PMID:26140779

  19. Aortic valve repair for papillary fibroelastoma.

    PubMed

    Di Marco, Luca; Al-Basheer, Amin; Glineur, David; Oppido, Guido; Di Bartolomeo, Roberto; El-Khoury, Gebrine

    2006-05-01

    We report the case of aortic valve-papillary fibroelastoma in a 66-year-old Belgian woman with a previous single episode of cerebral transient ischemic attack. Transthoracic two-dimensional echocardiography revealed a small mass adherent to the noncoronary cusp of the valve, which was confirmed by transesophageal echocardiography. Indication for surgery was performed because of a previous cerebral transient ischemic attack and for its potential risk of cerebral and coronary embolization. Surgical excision of the mass was performed with the need for glutaraldehyde-treated autologous pericardial patch repair of the aortic cusp. Intraoperative and postoperative transesophageal echocardiography both showed the valve to be competent. Postoperative recovery was uneventful. After a review of the literature, we conclude that, even if asymptomatic, and independent of their size, aortic valve papillary fibroelastomas justify surgical excision for their potential to systemic embolization. Moreover, we believe that a valve-sparing approach might be feasible with no recurrence after complete excision. PMID:16645416

  20. Incidental finding of a papillary fibroelastoma on the aortic valve in 16 slice multi-detector row computed tomography.

    PubMed

    Bootsveld, A; Puetz, J; Grube, E

    2004-06-01

    Papillary fibroelastoma (PFE) is a benign, rare, gelatinous tumour derived from the endocardium, primarily the cardiac valves, which is usually diagnosed by high resolution echocardiography. Although rarely clinically symptomatic, PFEs have a potential for coronary ischaemia, systemic embolisation with neurologic symptoms, and sometimes valvar dysfunction. There are reports of coronary occlusion and even sudden cardiac death due to a ball valve phenomenon on the coronary ostia. This report describes the characteristics of a PFE with multidetector 16 slice computed tomography and 1.5 Tesla cardiac magnetic resonance imaging. PMID:15145899

  1. Aortic Input Impedance during Nitroprusside Infusion

    PubMed Central

    Pepine, Carl J.; Nichols, W. W.; Curry, R. C.; Conti, C. Richard

    1979-01-01

    Beneficial effects of nitroprusside infusion in heart failure are purportedly a result of decreased afterload through “impedance” reduction. To study the effect of nitroprusside on vascular factors that determine the total load opposing left ventricular ejection, the total aortic input impedance spectrum was examined in 12 patients with heart failure (cardiac index <2.0 liters/min per m2 and left ventricular end diastolic pressure >20 mm Hg). This input impedance spectrum expresses both mean flow (resistance) and pulsatile flow (compliance and wave reflections) components of vascular load. Aortic root blood flow velocity and pressure were recorded continuously with a catheter-tip electromagnetic velocity probe in addition to left ventricular pressure. Small doses of nitroprusside (9-19 μg/min) altered the total aortic input impedance spectrum as significant (P < 0.05) reductions in both mean and pulsatile components were observed within 60-90 s. With these acute changes in vascular load, left ventricular end diastolic pressure declined (44%) and stroke volume increased (20%, both P < 0.05). Larger nitroprusside doses (20-38 μg/min) caused additional alteration in the aortic input impedance spectrum with further reduction in left ventricular end diastolic pressure and increase in stroke volume but no additional changes in the impedance spectrum or stroke volume occurred with 39-77 μg/min. Improved ventricular function persisted when aortic pressure was restored to control values with simultaneous phenylephrine infusion in three patients. These data indicate that nitroprusside acutely alters both the mean and pulsatile components of vascular load to effect improvement in ventricular function in patients with heart failure. The evidence presented suggests that it may be possible to reduce vascular load and improve ventricular function independent of aortic pressure reduction. PMID:457874

  2. Hollow Li20B60 Cage: Stability and Hydrogen Storage.

    PubMed

    Wang, Jing; Wei, Zhi-Jing; Zhao, Hui-Yan; Liu, Ying

    2016-01-01

    A stable hollow Li20B60 cage with D2 symmetry has been identified using first-principles density functional theory studies. The results of vibrational frequency analysis and molecular dynamics simulations demonstrate that this Li20B60 cage is exceptionally stable. The feasibility of functionalizing Li20B60 cage for hydrogen storage was explored theoretically. Our calculated results show that the Li20B60 molecule can adsorb a maximum of 28 hydrogen molecules. With a hydrogen uptake of 8.190 wt% and an average binding energy of 0.336 eV/H2, Li20B60 is a remarkable high-capacity storage medium. PMID:27076264

  3. Mapping Auditory Synaptic Circuits with Photostimulation of Caged Glutamate.

    PubMed

    Sturm, Joshua J; Nguyen, Tuan; Kandler, Karl

    2016-01-01

    Photostimulation of neurons with caged glutamate is a viable tool for mapping the strength and spatial distribution of synaptic networks in living brain slices. In photostimulation experiments, synaptic connectivity is assessed by eliciting action potentials in putative presynaptic neurons via focal photolysis of caged glutamate, while measuring postsynaptic responses via intracellular recordings. Two approaches are commonly used for delivering light to small, defined areas in the slice preparation; an optical fiber-based method and a laser-scanning-based method. In this chapter, we outline the technical bases for using photostimulation of caged glutamate to map synaptic circuits, and discuss the advantages and disadvantages of using fiber-based vs. laser-based systems. PMID:27259947

  4. Hollow Li20B60 Cage: Stability and Hydrogen Storage

    PubMed Central

    Wang, Jing; Wei, Zhi-Jing; Zhao, Hui-Yan; Liu, Ying

    2016-01-01

    A stable hollow Li20B60 cage with D2 symmetry has been identified using first-principles density functional theory studies. The results of vibrational frequency analysis and molecular dynamics simulations demonstrate that this Li20B60 cage is exceptionally stable. The feasibility of functionalizing Li20B60 cage for hydrogen storage was explored theoretically. Our calculated results show that the Li20B60 molecule can adsorb a maximum of 28 hydrogen molecules. With a hydrogen uptake of 8.190 wt% and an average binding energy of 0.336 eV/H2, Li20B60 is a remarkable high-capacity storage medium. PMID:27076264

  5. Biologically tunable reactivity of energetic nanomaterials using protein cages.

    PubMed

    Slocik, Joseph M; Crouse, Christopher A; Spowart, Jonathan E; Naik, Rajesh R

    2013-06-12

    The performance of aluminum nanomaterial based energetic formulations is dependent on the mass transport, diffusion distance, and stability of reactive components. Here we use a biologically inspired approach to direct the assembly of oxidizer loaded protein cages onto the surface of aluminum nanoparticles to improve reaction kinetics by reducing the diffusion distance between the reactants. Ferritin protein cages were loaded with ammonium perchlorate (AP) or iron oxide and assembled with nAl to create an oxidation-reduction based energetic reaction and the first demonstration of a nanoscale biobased thermite material. Both materials showed enhanced exothermic behavior in comparison to nanothermite mixtures of bulk free AP or synthesized iron oxide nanopowders prepared without the use of ferritin. In addition, by utilizing a layer-by-layer (LbL) process to build multiple layers of protein cages containing iron oxide and iron oxide/AP on nAl, stoichiometric conditions and energetic performance can be optimized. PMID:23713514

  6. Hollow Li20B60 Cage: Stability and Hydrogen Storage

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Wei, Zhi-Jing; Zhao, Hui-Yan; Liu, Ying

    2016-04-01

    A stable hollow Li20B60 cage with D2 symmetry has been identified using first-principles density functional theory studies. The results of vibrational frequency analysis and molecular dynamics simulations demonstrate that this Li20B60 cage is exceptionally stable. The feasibility of functionalizing Li20B60 cage for hydrogen storage was explored theoretically. Our calculated results show that the Li20B60 molecule can adsorb a maximum of 28 hydrogen molecules. With a hydrogen uptake of 8.190 wt% and an average binding energy of 0.336 eV/H2, Li20B60 is a remarkable high-capacity storage medium.

  7. Genes and Abdominal Aortic Aneurysm

    PubMed Central

    Hinterseher, Irene; Tromp, Gerard; Kuivaniemi, Helena

    2010-01-01

    Abdominal aortic aneurysm (AAA) is a multifactorial disease with a strong genetic component. Since first candidate gene studies were published 20 years ago, nearly 100 genetic association studies using single nucleotide polymorphisms (SNPs) in biologically relevant genes have been reported on AAA. The studies investigated SNPs in genes of the extracellular matrix, the cardiovascular system, the immune system, and signaling pathways. Very few studies were large enough to draw firm conclusions and very few results could be replicated in another sample set. The more recent unbiased approaches are family-based DNA linkage studies and genome-wide genetic association studies, which have the potential of identifying the genetic basis for AAA, if appropriately powered and well-characterized large AAA cohorts are used. SNPs associated with AAA have already been identified in these large multicenter studies. One significant association was of a variant in a gene called CNTN3 which is located on chromosome 3p12.3. Two follow-up studies, however, could not replicate the association. Two other SNPs, which are located on chromosome 9p21 and 9q33 were replicated in other samples. The two genes with the strongest supporting evidence of contribution to the genetic risk for AAA are the CDKN2BAS gene, also known as ANRIL, which encodes an antisense RNA that regulates expression of the cyclin-dependent kinase inhibitors CDKN2A and CDKN2B, and DAB2IP, which encodes an inhibitor of cell growth and survival. Functional studies are now needed to establish the mechanisms by which these genes contribute to AAA pathogenesis. PMID:21146954

  8. Aortic injuries in newer vehicles.

    PubMed

    Ryb, Gabriel E; Dischinger, Patricia C; Kleinberger, Michael; McGwin, Gerald; Griffin, Russell L

    2013-10-01

    The occurrence of AI was studied in relation to vehicle model year (MY) among front seat vehicular occupants, age≥16 in vehicles MY≥1994, entered in the National Automotive Sampling System Crashworthiness Data System between 1997 and 2010 to determine whether newer vehicles, due to their crashworthiness improvements, are linked to a lower risk of aortic injuries (AI). MY was categorized as 1994-1997, 1998-2004, or 2005-2010 reflecting the introduction of newer occupant protection technology. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals for the association between AI and MY independent of possible confounders. Analysis was repeated, stratified by frontal and near lateral impacts. AI occurred in 19,187 (0.06%) of the 31,221,007 (weighted) cases, and contributed to 11% of all deaths. AIs were associated with advanced age, male gender, high BMI, near-side impact, rollover, ejection, collision against a fixed object, high ΔV, vehicle mismatch, unrestrained status, and forward track position. Among frontal crashes, MY 98-04 and MY 05-10 showed increased adjusted odds of AI when compared to MY 94-97 [OR 1.84 (1.02-3.32) and 1.99 (0.93-4.26), respectively]. In contrast, among near-side impact crashes, MY 98-04 and MY 05-10 showed decreased adjusted odds of AI [OR 0.50 (0.25-0.99) and 0.27 (0.06-1.31), respectively]. While occupants of newer vehicles experience lower odds of AI in near side impact crashes, a higher AI risk is present in frontal crashes. PMID:23831451

  9. EXPERIMENTAL MODELLING OF AORTIC ANEURYSMS

    PubMed Central

    Doyle, Barry J; Corbett, Timothy J; Cloonan, Aidan J; O’Donnell, Michael R; Walsh, Michael T; Vorp, David A; McGloughlin, Timothy M

    2009-01-01

    A range of silicone rubbers were created based on existing commercially available materials. These silicones were designed to be visually different from one another and have distinct material properties, in particular, ultimate tensile strengths and tear strengths. In total, eleven silicone rubbers were manufactured, with the materials designed to have a range of increasing tensile strengths from approximately 2-4MPa, and increasing tear strengths from approximately 0.45-0.7N/mm. The variations in silicones were detected using a standard colour analysis technique. Calibration curves were then created relating colour intensity to individual material properties. All eleven materials were characterised and a 1st order Ogden strain energy function applied. Material coefficients were determined and examined for effectiveness. Six idealised abdominal aortic aneurysm models were also created using the two base materials of the study, with a further model created using a new mixing technique to create a rubber model with randomly assigned material properties. These models were then examined using videoextensometry and compared to numerical results. Colour analysis revealed a statistically significant linear relationship (p<0.0009) with both tensile strength and tear strength, allowing material strength to be determined using a non-destructive experimental technique. The effectiveness of this technique was assessed by comparing predicted material properties to experimentally measured methods, with good agreement in the results. Videoextensometry and numerical modelling revealed minor percentage differences, with all results achieving significance (p<0.0009). This study has successfully designed and developed a range of silicone rubbers that have unique colour intensities and material strengths. Strengths can be readily determined using a non-destructive analysis technique with proven effectiveness. These silicones may further aid towards an improved understanding of the

  10. Chronic rupture of abdominal aortic aneurysm.

    PubMed

    Kotsis, Thomas; Thomas, Kotsis; Tympa, Aliki; Aliki, Tympa; Kalinis, Aris; Aris, Kalinis; Vasilopoulos, Ioannis; Ioannis, Vasilopoulos; Theodoraki, Kassiani; Kassiani, Theodoraki

    2011-10-01

    Although the mortality rate after abdominal aortic aneurysm rupture approximates 90% despite the urgent management, a few cases of chronic rupture and delayed repair have been reported in the world literature; anatomic and hemodynamic reasons occasionally allow for the fortunate course of these patients. We report in this article the case of 76-year-old man with a ruptured abdominal aortic aneurysm who was transferred to our facility 4 weeks after his initial hospitalization in a district institution and who finally had a successful open repair. PMID:21620664

  11. Transcatheter aortic valve insertion (TAVI): a review

    PubMed Central

    Morgan-Hughes, G; Roobottom, C

    2014-01-01

    The introduction of transcatheter aortic valve insertion (TAVI) has transformed the care provided for patients with severe aortic stenosis. The uptake of this procedure is increasing rapidly, and clinicians from all disciplines are likely to increasingly encounter patients being assessed for or having undergone this intervention. Successful TAVI heavily relies on careful and comprehensive imaging assessment, before, during and after the procedure, using a range of modalities. This review outlines the background and development of TAVI, describes the nature of the procedure and considers the contribution of imaging techniques, both to successful intervention and to potential complications. PMID:24258463

  12. Supravalvular aortic stenosis after arterial switch operation.

    PubMed

    Maeda, Takuya; Koide, Masaaki; Kunii, Yoshifumi; Watanabe, Kazumasa; Kanzaki, Tomohito; Ohashi, Yuko

    2016-07-01

    Supravalvular aortic stenosis as a late complication of transposition of the great arteries is very rare, and only a few cases have been reported. We describe the case of a 14-year-old girl who developed supravalvular aortic stenosis as a late complication of the arterial switch operation for transposition of the great arteries. The narrowed ascending aorta was replaced with a graft. The right pulmonary artery was transected to approach the ascending aorta which adhered severely to the main pulmonary trunk, and we obtained a good operative field. PMID:25957091

  13. Transcatheter wiring of abdominal aortic aneurysm

    SciTech Connect

    Rossi, P.; Simonetti, G.; Passariello, R.; Stipa, S.; Cavallaro, A.

    1983-04-01

    A new technique of transcatheder wiring of unresectable aortic aneurysm is described that provides simultaneous transcatheder occlusion of both common iliac arteries followed by exillofemoral bypass. The spring coil used for aortic aneurysm wiring was of our own making. The outer portion of a movable core stainless steel guidewire was bent in a coil shape and introduced into the aneurysm through a 7 French Teflon catheder via the right femoral artery. The same catheder was also used for coil embolus occlusion of both iliac arteries.

  14. Chylous complications after abdominal aortic surgery.

    PubMed

    Haug, E S; Saether, O D; Odegaard, A; Johnsen, G; Myhre, H O

    1998-12-01

    Two patients developed chylous complications following abdominal aortic aneurysm repair. One patient had chylous ascitis and was successfully treated by a peritoneo-caval shunt. The other patient developed a lymph cyst, which gradually resorbed after puncture. Chylous complications following aortic surgery are rare. Patients in bad a general condition should be treated by initial paracentesis and total parenteral nutrition, supplemented by medium-chain triglyceride and low-fat diet. If no improvement is observed on this regimen, the next step should be implementation of a peritoneo-venous shunt, whereas direct ligation of the leak should be reserved for those who are not responding to this treatment. PMID:10204656

  15. Contemporary management of blunt aortic trauma.

    PubMed

    Dubose, J J; Azizzadeh, A; Estrera, A L; Safi, H J

    2015-10-01

    Blunt thoracic aortic injury (BTAI) remains a common cause of death following blunt mechanisms of trauma. Among patients who survive to reach hospital care, significant advances in diagnosis and treatment afford previously unattainable survival. The Society for Vascular Surgery (SVS) guidelines provide current best-evidence suggestions for treatment of BTAI. However, several key areas of controversy regarding optimal BTAI care remain. These include the refinement of selection criteria, timing for treatment and the need for long-term follow-up data. In addition, the advent of the Aortic Trauma Foundation (ATF) represents an important development in collaborative research in this field. PMID:25868973

  16. Caged compounds for multichromic optical interrogation of neural systems

    PubMed Central

    Amatrudo, Joseph M.; Olson, Jeremy P.; Agarwal, Hitesh K.; Ellis-Davies, Graham C.R.

    2014-01-01

    Caged compounds have widely used by neurophysiologists to study many aspects of cellular signaling in glia and neurons. Biologically inert before irradiation, they can be loaded into cells via patch pipette or topically applied in situ to a defined concentration, photolysis releases the caged compound in a very rapid and spatially defined way. Since caged compounds are exogenous optical probes, they include not only natural products such neurotransmitters, calcium and IP3, but non-natural products such as fluorophores, drugs and antibodies. In this Technical Spotlight we provide a short introduction to the uncaging technique by discussing the nitroaromatic caging chromophores most widely used in such experiments (e.g. CNB1, DMNB, MNI and CDNI). We show that recently developed caging chromophores (RuBi and DEAC450) that are photolyzed with blue light (ca. 430–480 nm range) can be combined with traditional nitroaromatic caged compounds to enable two-color optical probing of neuronal function. For example, one-photon uncaging of either RuBi-GABA or DEAC450-GABA with a 473-nm laser is facile, and can block non-linear currents (dendritic spikes or action potentials) evoked by two-photon uncaging of CDNI-Glu at 720 nm. We also show that two-photon uncaging of DEAC450-Glu and CDNI-GABA at 900 and 720 nm, respectively, can be used to fire and block action potentials. Our experiments illustrate that recently developed chromophores have taken uncaging out of the “monochrome era”, in which it has existed since 1978, so as to enable multichromic interrogation of neuronal function with single synapse precision. PMID:25471355

  17. Beveled reversed elephant trunk procedure for complex aortic aneurysm.

    PubMed

    Fujikawa, Takuya; Yamamoto, Shin; Sekine, Yuji; Oshima, Susumu; Kasai, Reo; Sasaguri, Shiro

    2016-03-01

    The reversed elephant trunk procedure uses an inverted graft for distal aortic replacement before aortic arch replacement in patients with mega aorta, to reduce the risk in the second stage. However, the conventional technique restricts the maximum diameter of the inverted graft to the aortic graft diameter. We employed a beveled reversed elephant trunk procedure to overcome the discrepancy between graft diameters in a 54-year-old woman with a severely twisted ascending aortic graft and enlarging chronic dissection of the aortic arch and descending thoracic aorta. The patient was discharged with a satisfactory repair and no neurologic deficit. PMID:25406402

  18. Fetal cardiac circulation in isolated aortic atresia assessed with ultrasound.

    PubMed

    Sayit, Aslı Tanrıvermiş; Ipek, Ali; Kurt, Aydın; Aghdasi, Bayan G; Arslan, Halil; Gümüş, Mehmet

    2012-01-01

    Congenital heart diseases are common, with an incidence of more than 8 in 1000 live births. Aortic atresia is a rare diagnosis and its prognosis is very poor. In this article, we present a case of isolated aortic atresia, a very rare cardiovascular anomaly, and its fetal ultrasound findings which include blood flow at foramen ovale from left to right, right deviation of the interventricular septum, dysfunction of the mitral valve and cardiomegaly. Aortic stenosis should be considered in the differential diagnosis of aortic atresia. However, in the case of severe aortic stenosis and/or accompanying ventricular septal defect, differential diagnosis may not be done. PMID:24592058

  19. Laboratory animal welfare: cage enrichment and mouse behaviour.

    PubMed

    Wolfer, David P; Litvin, Oxana; Morf, Samuel; Nitsch, Roger M; Lipp, Hans-Peter; Würbel, Hanno

    2004-12-16

    Mice housed in standard cages show impaired brain development, abnormal repetitive behaviours (stereotypies) and an anxious behavioural profile, all of which can be lessened by making the cage environment more stimulating. But concerns have been raised that enriched housing might disrupt standardization and so affect the precision and reproducibility of behavioural-test results (for example, see ref. 4). Here we show that environmental enrichment increases neither individual variability in behavioural tests nor the risk of obtaining conflicting data in replicate studies. Our findings indicate that the housing conditions of laboratory mice can be markedly improved without affecting the standardization of results. PMID:15602544

  20. Study for elevator cage position during the braking period

    NASA Astrophysics Data System (ADS)

    Ungureanu, M.; Crăciun, I.; Bănică, M.; Dăscălescu, A.

    2016-08-01

    An important problem in order to study an elevator cage position for its braking period is to establish a correlation between the studies in the fields of mechanics and electric. The classical approaches to establish the elevator kinematic parameters are position, velocity and acceleration, but the last studies performed in order to determine the positioning performed by introducing supplementary another parameter - the jerk- which is derived with respect to time of acceleration. Thus we get a precise method for cage motion control for third-order trajectory planning.

  1. Equivalence Between Squirrel Cage and Sheet Rotor Induction Motor

    NASA Astrophysics Data System (ADS)

    Dwivedi, Ankita; Singh, S. K.; Srivastava, R. K.

    2015-03-01

    Due to topological changes in dual stator induction motor and high cost of its fabrication, it is convenient to replace the squirrel cage rotor with a composite sheet rotor. For an experimental machine, the inner and outer stator stampings are normally available whereas the procurement of rotor stampings is quite cumbersome and is not always cost effective. In this paper, the equivalence between sheet/solid rotor induction motor and squirrel cage induction motor has been investigated using layer theory of electrical machines, so as to enable one to utilize sheet/solid rotor in dual port experimental machines.

  2. Caged xanthones: Potent inhibitors of global predominant MRSA USA300.

    PubMed

    Chaiyakunvat, Pongkorn; Anantachoke, Natthinee; Reutrakul, Vichai; Jiarpinitnun, Chutima

    2016-07-01

    Total of 22 caged xanthones were subjected to susceptibility testing of global epidemic MRSA USA300. Natural morellic acid showed the strongest potency (MIC of 12.5μM). However, its potent toxicity diminishes MRSA therapeutic potential. We synthetically modified natural morellic acid to yield 13 derivatives (3a-3m). Synthetically modified 3b retained strong potency in MRSA growth inhibition, yet the toxicity was 20-fold less than natural morellic acid, permitting the possibility of using caged xanthones for MRSA therapeutic. PMID:27216998

  3. Equivalence Between Squirrel Cage and Sheet Rotor Induction Motor

    NASA Astrophysics Data System (ADS)

    Dwivedi, Ankita; Singh, S. K.; Srivastava, R. K.

    2016-06-01

    Due to topological changes in dual stator induction motor and high cost of its fabrication, it is convenient to replace the squirrel cage rotor with a composite sheet rotor. For an experimental machine, the inner and outer stator stampings are normally available whereas the procurement of rotor stampings is quite cumbersome and is not always cost effective. In this paper, the equivalence between sheet/solid rotor induction motor and squirrel cage induction motor has been investigated using layer theory of electrical machines, so as to enable one to utilize sheet/solid rotor in dual port experimental machines.

  4. Cholate-Based Synthesis of Size-Tunable Cage Compounds

    PubMed Central

    2015-01-01

    We describe cholate-based cage amphiphiles with a unique architecture that combines elements of structural rigidity and flexibility. The cage compounds are built by extending and bridging three polar chains underneath the concave steroid rings of cholate and capping with another rigid, symmetrically trifunctionalized cyanuric acid moiety. The connecting chains are varied to include, for instance, oligo(ethylene glycol) or chains containing 1,2,3-triazole units to present flexibility in the chemical and structural space and potentially deliver functional molecules for molecular recognition applications. PMID:25536149

  5. 14C-age tracers in global ocean circulation models

    NASA Astrophysics Data System (ADS)

    Koeve, W.; Wagner, H.; Kähler, P.; Oschlies, A.

    2014-10-01

    The natural abundance of 14C in total CO2 dissolved in seawater is a property applied to evaluate the water age structure and circulation in the ocean and in ocean models. In this study we use three different representations of the global ocean circulation augmented with a suite of idealised tracers to study the potential and limitations of using natural 14C to determine water age, the time elapsed since a body of water had contact with the atmosphere. We find that, globally, bulk 14C-age is dominated by two equally important components, one associated with aging, i.e. the time component of circulation and one associated with a "preformed 14C-age". This latter quantity exists because of the slow and incomplete atmosphere/ocean equilibration of 14C in particular in high latitudes where many water masses form. The relative contribution of the preformed component to bulk 14C-age varies regionally within a given model, but also between models. Regional variability, e.g. in the Atlantic Ocean is associated with the mixing of waters with very different end members of preformed 14C-age. In the Atlantic, variations in the preformed component over space and time mask the circulation component to an extent that its patterns are not detectable from bulk 14C-age alone. Between models the variability of age can also be considerable (factor of 2), related to the combinations of physical model parameters, which influence circulation dynamics, and gas exchange in the models. The preformed component was found to be very sensitive to gas exchange and moderately sensitive to ice cover. In our model evaluation exercise, the choice of the gas exchange constant from within the current range of uncertainty had such a strong influence on preformed and bulk 14C-age that if model evaluation would be based on bulk 14C-age it could easily impair the evaluation and tuning of a models circulation on global and regional scales. Based on the results of this study, we propose that considering

  6. A Post-Functionalizable Iso-Polyoxotitanate Cage Cluster.

    PubMed

    Hou, Jie; Hu, Junyi; Sun, Qing; Zhang, Guanyun; Tung, Chen-Ho; Wang, Yifeng

    2016-07-18

    During solvothermal alcoholysis of a mixture of TiI4 and Ti(O(i)Pr)4, a {I@Ti22} cage cluster encapsulating an OH and iodide guests is crystallized. The {I@Ti22} host-guest cluster surface is postfunctionalizable with catecholate and carboxylate ligands. The synthetic details, structural characterization, spectroscopic properties of the obtained cages clusters are provided. The present study provides candidates for modeling ligand exchange and electron-hole transfer at the titanate nanoparticle surface, and meanwhile offers new opportunities for understanding the TiO2 nanocrystalline formation in solvothermal processes. PMID:27351728

  7. Reproductive performance of mice in disposable and standard individually ventilated cages.

    PubMed

    Ferguson, Danielle R; Bailey, Michele M

    2013-01-01

    This study assessed the reproductive performance of mice housed in 2 types of individually ventilated caging systems. Breeding pairs from 48 female and 24 male mice of 3 established transgenic mouse breeding colonies were placed in either a standard or disposable ventilated caging system. For 3 breeding cycles, the number of pups born, pup survival rate to weaning, time interval between litters, and pup weights were monitored for each breeding pair. Disposable and standard cages were maintained in the same location during breeding. Environmental parameters included intracage temperature, humidity, and ammonia and carbon dioxide levels and room light intensity and sound. Overall, 776 offspring were produced. Breeding performance did not differ significantly between the 2 cage types. By 11 wk of age, the weights of pups from both cage types were equivalent. The intracage temperature was 1.1 °F warmer and light intensity at the site of the nest was 34 lx dimmer in disposable cages than in standard caging. The difference in lighting likely was due to nest location; the nests in the disposable cages were at the back of the cages and away from the anterior air supply, whereas in standard caging, nests were at the front of the cages, with the air supply at the rear. Under these husbandry conditions, mice housed in disposable caging systems have comparable breeding performance to those housed in standard individually ventilated cages. PMID:23849403

  8. [Emergency stent placement after descending aortic replacement with chronic aortic dissection].

    PubMed

    Shiraishi, Manabu; Muraoka, Arata; Aizawa, Kei; Sakano, Yasuhito; Kaminishi, Yuichiro; Ohki, Shinichi; Saito, Tsutomu; Misawa, Yoshio

    2011-09-01

    A 49-year-old man with asymptomatic chronic aneurysmal dissection was admitted to our hospital. He had undergone ascending aortic replacement for type A aortic dissection 7 months before. We performed descending aortic replacement for chronic aneurysmal dissection. Renal dysfunction appeared 1 day after the operation. Contrast-enhanced computed tomography indicated that the true lumen was severely compressed by a false lumen, and that the origins of the renal artery were occluded. We performed emergency endovascular stent placement to dilate the true lumen. Immediately after this procedure, renal ischemia improved. The postoperative course was uneventful. An endovascular approach using bare stent can be a treatment option that is less invasive and prompter for a patient with renal ischemia resulting from aortic dissection. PMID:21899124

  9. Computed tomography angiography of hybrid thoracic endovascular aortic repair of the aortic arch.

    PubMed

    Akhtar, Nila J; Oderich, Gustavo S; Vrtiska, Terri J; Williamson, Eric E; Araoz, Philip A

    2013-05-01

    Endovascular repair of the aorta has traditionally been limited to the abdominal aorta and, more recently, the descending thoracic aorta. However, recently hybrid repairs (a combination of open surgical and endovascular repair) have made endovascular repair of the aortic arch possible. Hybrid repair of the aortic arch typically involves an open surgical debranching procedure that allows for revascularization of the aortic arch vessels and subsequent endovascular stent placement. These approaches avoid the deep hypothermic circulatory arrest required for full, open surgical repair of the aortic arch. In hybrid repairs, the stent landing zone determines which branch vessels will be covered and therefore need revascularization. This article will review the preprocedure assessment with computed tomography angiography, techniques for revascularization and postprocedure complications. PMID:23621141

  10. Comparison of Clinical and Radiologic Results between Expandable Cages and Titanium Mesh Cages for Thoracolumbar Burst Fracture

    PubMed Central

    Lee, Gwang-Jun; Hur, Hyuk; Jang, Jae-Won; Kim, Tae-Sun; Kim, Soo-Han

    2014-01-01

    Objective A thoracolumbar burst fracture is usually unstable and can cause neurological deficits and angular deformity. Patients with unstable thoracolumbar burst fracture usually need surgery for decompression of the spinal canal, correction of the angular deformity, and stabilization of the spinal column. We compared two struts, titanium mesh cages (TMCs) and expandable cages. Methods 33 patients, who underwent anterior thoracolumbar reconstruction using either TMCs (n=16) or expandable cages (n=17) between June 2000 and September 2011 were included in this study. Clinical outcome was measured by visual analogue scale (VAS), American Spinal Injury Association (ASIA) scale and Low Back Outcome Score (LBOS) for functional neurological evaluation. The Cobb angle, body height of the fractured vertebra, the operation time and amount of intra-operative bleeding were measured in both groups. Results In the expandable cage group, operation time and amount of intraoperative blood loss were lower than that in the TMC group. The mean VAS scores and LBOS in both groups were improved, but no significant difference. Cobb angle was corrected higher than that in expandable cage group from postoperative to the last follow-up. The change in Cobb angles between preoperative, postoperative, and the last follow-up did not show any significant difference. There was no difference in the subsidence of anterior body height between both groups. Conclusion There was no significant difference in the change in Cobb angles with an inter-group comparison, the expandable cage group showed better results in loss of kyphosis correction, operation time, and amount of intraoperative blood loss. PMID:24851149

  11. Highly-efficient synthesis of covalent porphyrinic cages via DABCO-templated imine condensation reactions.

    PubMed

    Ding, Huimin; Meng, Xiangshi; Cui, Xu; Yang, Yihui; Zhou, Tailin; Wang, Caixing; Zeller, Matthias; Wang, Cheng

    2014-10-01

    We report a new approach to construct covalent porphyrinic cages with different spacer lengths, in which the cage compounds have been conveniently synthesized in quantitative yields, via DABCO-templated imine condensation reactions. PMID:25111246

  12. Biomechanical factors in the biology of aortic wall and aortic valve diseases

    PubMed Central

    Bäck, Magnus; Gasser, T. Christian; Michel, Jean-Baptiste; Caligiuri, Giuseppina

    2013-01-01

    The biomechanical factors that result from the haemodynamic load on the cardiovascular system are a common denominator of several vascular pathologies. Thickening and calcification of the aortic valve will lead to reduced opening and the development of left ventricular outflow obstruction, referred to as aortic valve stenosis. The most common pathology of the aorta is the formation of an aneurysm, morphologically defined as a progressive dilatation of a vessel segment by more than 50% of its normal diameter. The aortic valve is exposed to both haemodynamic forces and structural leaflet deformation as it opens and closes with each heartbeat to assure unidirectional flow from the left ventricle to the aorta. The arterial pressure is translated into tension-dominated mechanical wall stress in the aorta. In addition, stress and strain are related through the aortic stiffness. Furthermore, blood flow over the valvular and vascular endothelial layer induces wall shear stress. Several pathophysiological processes of aortic valve stenosis and aortic aneurysms, such as macromolecule transport, gene expression alterations, cell death pathways, calcification, inflammation, and neoangiogenesis directly depend on biomechanical factors. PMID:23459103

  13. Aortic valve replacement with sutureless and rapid deployment aortic valve prostheses.

    PubMed

    Berretta, Paolo; Di Eusanio, Marco

    2016-09-01

    Aortic valve stenosis is the most common valve disease in the western world. Over the past few years the number of aortic valve replacement (AVR) interventions has increased with outcomes that have been improved despite increasing age of patients and increasing burden of comorbidities. However, despite such excellent results and its well-established position, conventional AVR has undergone great development over the previous two decades. Such progress, by way of less invasive incisions and use of new technologies, including transcatheter aortic valve implantation and sutureless valve prostheses, is intended to reduce the traumatic impact of the surgical procedure, thus fulfilling lower risk patients' expectations on the one hand, and extending the operability toward increasingly high-risk patients on the other. Sutureless and rapid deployment aortic valves are biological, pericardial prostheses that anchor within the aortic annulus with no more than three sutures. The sutureless prostheses, by avoiding the passage and the tying of the sutures, significantly reduce operative times and may improve outcomes. However, there is still a paucity of robust, evidence-based data on the role and performance of sutureless AVR. Therefore, strongest long-term data, randomized studies and registry data are required to adequately assess the durability and long-term outcomes of sutureless aortic valve replacement. PMID:27582765

  14. [Emergency Thoracic Endovascular Aortic Repair of Ruptured Kommerell's Diverticulum with an Acute Aortic Dissection].

    PubMed

    Seguchi, Ryuta; Ohtake, Hiroshi; Yoshimura, Takahiro; Shintani, Yoshiko; Nishida, Yuji; Kiuchi, Ryuta; Yamaguchi, Shojiro; Tomita, Shigeyuki; Sanada, Junichiro; Matsui, Osamu; Watanabe, Go

    2016-06-01

    This case report describes emergency thoracic endovascular aortic repair (TEVAR) of a ruptured Kommerell's diverticulum associated with a type B acute aortic dissection in a patient with a right aortic arch. A 64-year-old male was admitted with symptoms of sudden paraplegia and shock. The computed tomography imaging showed right aortic arch anomaly, with mirror image branching of the major arteries. The aorta was dissected from the origin of the right subclavian artery to the terminal aorta, with a thrombosed false lumen. Rupture was found in a 6.3 cm aneurysm located in the distal arch, which was diagnosed as Kommerell's diverticulum. We performed emergency TEVAR, and the aneurysm was successfully excluded using deployment of a Gore Tag stent-graft. At 3 months' follow-up, the patient was doing well and showed shrinkage of the aneurysm was confirmed. TEVAR is considered to be a suitable procedure for an emergency aortic catastrophe even in patients with aortic anomaly. PMID:27246128

  15. Aortic valve replacement with sutureless and rapid deployment aortic valve prostheses

    PubMed Central

    Berretta, Paolo; Di Eusanio, Marco

    2016-01-01

    Aortic valve stenosis is the most common valve disease in the western world. Over the past few years the number of aortic valve replacement (AVR) interventions has increased with outcomes that have been improved despite increasing age of patients and increasing burden of comorbidities. However, despite such excellent results and its well-established position, conventional AVR has undergone great development over the previous two decades. Such progress, by way of less invasive incisions and use of new technologies, including transcatheter aortic valve implantation and sutureless valve prostheses, is intended to reduce the traumatic impact of the surgical procedure, thus fulfilling lower risk patients' expectations on the one hand, and extending the operability toward increasingly high-risk patients on the other. Sutureless and rapid deployment aortic valves are biological, pericardial prostheses that anchor within the aortic annulus with no more than three sutures. The sutureless prostheses, by avoiding the passage and the tying of the sutures, significantly reduce operative times and may improve outcomes. However, there is still a paucity of robust, evidence-based data on the role and performance of sutureless AVR. Therefore, strongest long-term data, randomized studies and registry data are required to adequately assess the durability and long-term outcomes of sutureless aortic valve replacement. PMID:27582765

  16. Ultrasonic delineation of aortic microstructure: The relative contribution of elastin and collagen to aortic elasticity

    NASA Astrophysics Data System (ADS)

    Marsh, Jon N.; Takiuchi, Shin; Lin, Shiow Jiuan; Lanza, Gregory M.; Wickline, Samuel A.

    2004-05-01

    Aortic elasticity is an important factor in hemodynamic health, and compromised aortic compliance affects not only arterial dynamics but also myocardial function. A variety of pathologic processes (e.g., diabetes, Marfan's syndrome, hypertension) can affect aortic elasticity by altering the microstructure and composition of the elastin and collagen fiber networks within the tunica media. Ultrasound tissue characterization techniques can be used to obtain direct measurements of the stiffness coefficients of aorta by measurement of the speed of sound in specific directions. In this study we sought to define the contributions of elastin and collagen to the mechanical properties of aortic media by measuring the magnitude and directional dependence of the speed of sound before and after selective isolation of either the collagen or elastin fiber matrix. Formalin-fixed porcine aortas were sectioned for insonification in the circumferential, longitudinal, or radial direction and examined using high-frequency (50 MHz) ultrasound microscopy. Isolation of the collagen or elastin fiber matrices was accomplished through treatment with NaOH or formic acid, respectively. The results suggest that elastin is the primary contributor to aortic medial stiffness in the unloaded state, and that there is relatively little anisotropy in the speed of sound or stiffness in the aortic wall.

  17. A novel test cage with an air ventilation system as an alternative to conventional cages for the efficacy testing of mosquito repellents.

    PubMed

    Obermayr, U; Rose, A; Geier, M

    2010-11-01

    We have developed a novel test cage and improved method for the evaluation of mosquito repellents. The method is compatible with the United States Environmental Protection Agency, 2000 draft OPPTS 810.3700 Product Performance Test Guidelines for Testing of Insect Repellents. The Biogents cages (BG-cages) require fewer test mosquitoes than conventional cages and are more comfortable for the human volunteers. The novel cage allows a section of treated forearm from a volunteer to be exposed to mosquito probing through a window. This design minimizes residual contamination of cage surfaces with repellent. In addition, an air ventilation system supplies conditioned air to the cages after each single test, to flush out and prevent any accumulation of test substances. During biting activity tests, the untreated skin surface does not receive bites because of a screen placed 150 mm above the skin. Compared with the OPPTS 810.3700 method, the BG-cage is smaller (27 liters, compared with 56 liters) and contains 30 rather than hundreds of blood-hungry female mosquitoes. We compared the performance of a proprietary repellent formulation containing 20% KBR3023 with four volunteers on Aedes aegypti (L.) (Diptera: Culicidae) in BG- and conventional cages. Repellent protection time was shorter in tests conducted with conventional cages. The average 95% protection time was 4.5 +/- 0.4 h in conventional cages and 7.5 +/- 0.6 h in the novel BG-cages. The protection times measured in BG-cages were more similar to the protection times determined with these repellents in field tests. PMID:21175061

  18. Long-Term Changes in the Distal Aorta after Aortic Arch Replacement in Acute DeBakey Type I Aortic Dissection

    PubMed Central

    Cho, Kwangjo; Jeong, Jeahwa; Park, Jongyoon; Yun, Sungsil; Woo, Jongsu

    2016-01-01

    Background We analyzed the long-term results of ascending aortic replacement and arch aortic replacement in acute DeBakey type I aortic dissections to measure the differences in the distal aortic changes with extension of the aortic replacement. Methods We reviewed 142 cases of acute DeBakey type I aortic dissections (1996–2015). Seventy percent of the cases were ascending aortic replacements, and 30% of the cases underwent total arch aortic replacement, which includes the aorta from the root to the beginning of the descending aorta with the 3 arch branches. Fourteen percent (20 cases) resulted in surgical mortality and 86% of cases that survived had a mean follow-up period of 6.6±4.6 years. Among these cases, 64% of the patients were followed up with computed tomography (CT) angiograms with the duration of the final CT check period of 4.9±2.9 years. Results There were 15 cases of reoperation in 13 patients. Of these 15 cases, 13 cases were in the ascending aortic replacement group and 2 cases were in the total arch aortic replacement group. Late mortality occurred in 13 cases; 10 cases were in the ascending aortic replacement group and 3 cases were in the total arch aortic replacement group. Eight patients died of a distal aortic problem in the ascending aortic replacement group, and 1 patient died of distal aortic rupture in the total arch aortic replacement group. The follow-up CT angiogram showed that 69.8% of the ascending aortic replacement group and 35.7% of the total arch aortic replacement group developed distal aortic dilatation (p=0.0022). Conclusion The total arch aortic replacement procedure developed fewer distal remnant aortic problems from dilatation than the ascending aortic replacement procedure in acute type I aortic dissections. PMID:27525235

  19. Fatal Saccharomyces Cerevisiae Aortic Graft Infection

    NASA Technical Reports Server (NTRS)

    Meyer, Michael (Technical Monitor); Smith, Davey; Metzgar, David; Wills, Christopher; Fierer, Joshua

    2002-01-01

    Saccharomyces cerevisiae is a yeast commonly used in baking and a frequent colonizer of human mucosal surfaces. It is considered relatively nonpathogenic in immunocompetent adults. We present a case of S. cerevisiae fungemia and aortic graft infection in an immunocompetent adult. This is the first reported case of S. cerevisiue fungemia where the identity of the pathogen was confirmed by rRNA sequencing.

  20. Endovascular aortic repair: first twenty years.

    PubMed

    Koncar, Igor; Tolić, Momcilo; Ilić, Nikola; Cvetković, Slobodan; Dragas, Marko; Cinara, Ilijas; Kostić, Dusan; Davidović, Lazar

    2012-01-01

    Endovascular aortic/aneurysm repair (EVAR) was introduced into clinical practice at the beginning of the nineties. Its fast development had a great influence on clinicians, vascular surgeons and interventional radiologists, educational curriculums, patients, industry and medical insurance. The aim of this paper is to present the contribution of clinicians and industry to the development and advancement of endovascular aortic repair over the last 20 years. This review article presents the development of EVAR by focusing on the contribution of physicians, surgeons and interventional radiologists in the creation of the new field of vascular surgery termed hybrid vascular surgery, and also the contribution of technological advancement by a significant help of industrial representatives--engineers and their counselors. This article also analyzes studies conducted in order to compare the successfulness of EVAR with up-to-now applied open surgical repair of aortic aneurysms, and some treatment techniques of other aortic diseases. During the first two decades of its development the EVAR method was rapidly progressing and was adopted concurrently with the expansion of technology. Owing to large randomized studies, early and long-term results indicate specific complications of this method, thus influencing further technological improvement and defining risk patients groups in whom the use of the technique should be avoided. Good results are insured only in centers, specialized in vascular surgery, which have on their disposal adequate conditions for solving all complications associated with this method. PMID:23350259

  1. Idiopathic Aortic Root to Right Atrial Fistula.

    PubMed

    Campisi, Salvatore; Cluzel, Armand; Vola, Marco; Fuzellier, Jean Francois

    2016-06-01

    An aorta to right atrium fistula is rare. We report a case of idiopathic aortic root to right atrial fistula with right heart failure and review the literature. doi: 10.1111/jocs.12751 (J Card Surg 2016;31:373-375). PMID:27109166

  2. MicroRNAs in aortic disease.

    PubMed

    Vavuranakis, Manolis; Kariori, Maria; Vrachatis, Dimitrios; Aznaouridis, Konstantinos; Siasos, Gerasimos; Kokkou, Eleni; Mazaris, Savvas; Moldovan, Carmen; Kalogeras, Konstantinos; Tousoulis, Dimitris; Stefanadis, Christodoulos

    2013-01-01

    MicroRNAs (miRNAs) are non-coding RNAs of ~22 nucleotides which act as down regulators of gene expression in the post-transcription level and/or in the translation level. Several studies have shown that the process of their maturation is rather crucial for the development of cardiovascular system thus their regulation (up-,down-) is implicated with many cardiac pathologies. This is evaluated through their circulating levels which are reliable, stable and the changes in their serum profiles are representative of tissue alterations serum levels. Furthermore, they have been shown to participate in cardiovascular disease pathogenesis including atherosclerosis, coronary artery disease, myocardial infarction, heart failure cardiac arrhythmias and aortic stenosis. In the present review, we will first describe i) the process of miRNAs' maturation ii) their role in the cardiovascular development, iii) their role as biomarkers of cardiac diseases, iv) the cardiac myo-miR families and the v) their role in cardiac remodeling and the development of cardiac diseases. Second we will review the miRNA families that participate in aortic stenosis separated according to its main pathways (imflammation, fibrosis, calcification). Finally, we will describe the miRNAs that participate in the development of aortic aneurysm and aortic dissection according to their serum levels. PMID:23745808

  3. Infected Abdominal Aortic Aneurysm with Helicobacter cinaedi

    PubMed Central

    Iwasawa, Takamasa; Tamura, Atsushi; Lefor, Alan T.

    2016-01-01

    Helicobacter cinaedi is a rare human pathogen which has various clinical manifestations such as cellulitis, bacteremia, arthritis, meningitis, and infectious endocarditis. We report an abdominal aortic aneurysm infected with Helicobacter cinaedi, treated successfully with surgical repair and long-term antimicrobial therapy. PMID:26885430

  4. Painless Aortic Dissection Presenting as Paraplegia

    PubMed Central

    Colak, Necmettin; Nazli, Yunus; Alpay, Mehmet Fatih; Akkaya, Ismail Olgun; Cakir, Omer

    2012-01-01

    Acute dissection of the aorta can be life-threatening. As a presenting manifestation of aortic dissection, neurologic complications such as paraplegia are rare. Herein, we report the case of a 51-year-old man who presented with sudden-onset paraplegia and ischemia of the legs, with no chest or back pain. His medical history included coronary artery bypass grafting. Physical examination revealed pulseless lower extremities, and computed tomography showed aortic dissection from the ascending aorta to the common iliac arteries bilaterally. A lumbar catheter was inserted for cerebrospinal fluid drainage, and axillary arterial cannulation was established. With the use of cardiopulmonary bypass, the aortic dissection was corrected, and the previous coronary artery grafts were reattached. The surgery restored spinal and lower-extremity perfusion, and the patient walked unaided from the hospital upon his discharge 5 days later. Although acute aortic dissection presenting as paraplegia is rare, it should be considered in patients who have pulseless femoral arteries bilaterally and sudden-onset paraplegia, despite no pain in the chest or back. Prompt diagnosis and intervention can prevent morbidity and death. PMID:22740752

  5. [Syphilitic aortic regurgitation: a sexually transmissible cardiopathy].

    PubMed

    Madani, M; Rissoul, K; Ajjaja, M R; Moutaouakkil, E M; Arji, M; Chikhaoui, Y; Rahali, M; Slaoui, A

    2013-04-01

    Syphilitic cardiovascular complications are currently rare. It concerns the tertiary phase of the disease and results in sacciform aneurysm of the thoracic aorta or ostial coronary artery stenosis. Syphilitic aortic regurgitation is even more rare. We illustrate it by a clinical observation and discuss its diagnosis and its treatment. PMID:21663893

  6. Intraoperative aortic dissection in pediatric heart surgery.

    PubMed

    Hibino, Narutoshi; Harada, Yorikazu; Hiramatsu, Takeshi; Yasukochi, Satoshi; Satomi, Gengi

    2006-06-01

    Intraoperative aortic dissection occurred in a 3-year-old-boy undergoing repair of an atrial septal defect. Transesophageal echocardiography was useful for the diagnosis, and conservative medical treatment under close observation was feasible in this case which involved a limited intimal tear. PMID:16714685

  7. Multimodality Imaging Approach towards Primary Aortic Sarcomas Arising after Endovascular Abdominal Aortic Aneurysm Repair: Case Series Report.

    PubMed

    Kamran, Mudassar; Fowler, Kathryn J; Mellnick, Vincent M; Sicard, Gregorio A; Narra, Vamsi R

    2016-06-01

    Primary aortic neoplasms are rare. Aortic sarcoma arising after endovascular aneurysm repair (EVAR) is a scarce subset of primary aortic malignancies, reports of which are infrequent in the published literature. The diagnosis of aortic sarcoma is challenging due to its non-specific clinical presentation, and the prognosis is poor due to delayed diagnosis, rapid proliferation, and propensity for metastasis. Post-EVAR, aortic sarcomas may mimic other more common aortic processes on surveillance imaging. Radiologists are rarely knowledgeable about this rare entity for which multimodality imaging and awareness are invaluable in early diagnosis. A series of three pathologically confirmed cases are presented to display the multimodality imaging features and clinical presentations of aortic sarcoma arising after EVAR. PMID:26721588

  8. [Thoracic Endovascular Aortic Aneurysm Repair in a Young Patient with Descending Aortic Injury;Report of a Case].

    PubMed

    No, Hironari; Nishida, Satoru; Takagi, Takeshi; Mohri, Ryosuke

    2016-08-01

    A 15-year-old boy was referred to our emergency room due to a penetrating injury of the back. Computed tomography( CT) demonstrated a descending aortic injury at the Th9/10 level, bilateral hemothorax, and spinal cord injury. Although surgical treatment was indicated, multiple organ injury complicated open surgical repair, which required cardiopulmonary bypass with full heparinization. Therefore, the patient was scheduled to undergo thoracic endovascular aortic repair (TEVAR). A 23×33-mm Excluder aortic extension cuff was chosen for the small, 15-mm diameter aorta. The aortic extension was delivered and deployed in the descending aorta. Postoperative CT demonstrated neither endoleak nor collapse of the stent-graft. TEVAR for traumatic aortic aneurysm appears to be safe and effective, and an aortic extension for an abdominal aortic aneurysm may be utilized as an alternative device if the patient is young and the aorta is small. PMID:27476569

  9. Clinical outcomes of two types of cages used in transforaminal lumbar interbody fusion for the treatment of degenerative lumbar diseases: n-HA/PA66 cages versus PEEK cages.

    PubMed

    Deng, Qian-xing; Ou, Yun-sheng; Zhu, Yong; Zhao, Zeng-hui; Liu, Bo; Huang, Qiu; Du, Xing; Jiang, Dian-ming

    2016-06-01

    This study reports the clinical effects of nano-hydroxyapatite/polyamide66 cages (n-HA/PA66 cages) and compares the clinical outcomes between n-HA/PA66 and polyetheretherketone cages (PEEK cages) for application in transforaminal lumbar interbody fusion (TLIF). A retrospective and case-control study involving 124 patients using n-HA/PA66 cages and 142 patients using PEEK cages was conducted. All patients underwent TLIF and had an average of 2-years of follow-up. The Oswestry Disability Index and Visual Analog Scale were selected to assess the pain of low back and leg, as well as neurological status. The intervertebral space height and segmental angle were also measured to estimate the radiological changes. At the 1-year and final follow-ups, the fusion and subsidence rates were evaluated. There was no significant difference between the two groups regarding clinical and radiological results. At the final follow-up, the bony fusion rate was 92.45 and 91.57 % for the n-HA/PA66 and PEEK groups, respectively, and the subsidence rate was 7.55 and 8.99 %, respectively. The study indicated that both n-HA/PA66 and PEEK cages could promote effective clinical and radiographic outcomes when used to treat degenerative lumbar diseases. The high fusion and low subsidence rates revealed that n-HA/PA66 cages could be an alternative ideal choice as the same to PEEK cages for lumbar reconstruction after TLIF. PMID:27091044

  10. Flexible, symmetry-directed approach to assembling protein cages.

    PubMed

    Sciore, Aaron; Su, Min; Koldewey, Philipp; Eschweiler, Joseph D; Diffley, Kelsey A; Linhares, Brian M; Ruotolo, Brandon T; Bardwell, James C A; Skiniotis, Georgios; Marsh, E Neil G

    2016-08-01

    The assembly of individual protein subunits into large-scale symmetrical structures is widespread in nature and confers new biological properties. Engineered protein assemblies have potential applications in nanotechnology and medicine; however, a major challenge in engineering assemblies de novo has been to design interactions between the protein subunits so that they specifically assemble into the desired structure. Here we demonstrate a simple, generalizable approach to assemble proteins into cage-like structures that uses short de novo designed coiled-coil domains to mediate assembly. We assembled eight copies of a C3-symmetric trimeric esterase into a well-defined octahedral protein cage by appending a C4-symmetric coiled-coil domain to the protein through a short, flexible linker sequence, with the approximate length of the linker sequence determined by computational modeling. The structure of the cage was verified using a combination of analytical ultracentrifugation, native electrospray mass spectrometry, and negative stain and cryoelectron microscopy. For the protein cage to assemble correctly, it was necessary to optimize the length of the linker sequence. This observation suggests that flexibility between the two protein domains is important to allow the protein subunits sufficient freedom to assemble into the geometry specified by the combination of C4 and C3 symmetry elements. Because this approach is inherently modular and places minimal requirements on the structural features of the protein building blocks, it could be extended to assemble a wide variety of proteins into structures with different symmetries. PMID:27432965

  11. CAGE FOR USE WITH SMALL AQUATIC ANIMALS IN FIELD STUDIES

    EPA Science Inventory

    Various cages are frequently used in assessing the effects of pesticides on non-target animals. In some cases, small animals offer advantages over larger ones because they may be more economical to raise in the laboratory or to purchase; immature stages often are more sensitive t...

  12. Metal Atom Endohedrally Doped C20 CAGE Structure:

    NASA Astrophysics Data System (ADS)

    Erkoç, Şakir

    The C20 cage structure (X@C20; X =Fe, Co, Ni) endohedrally doped with a metal atom has been investigated theoretically by performing molecular-mechanics optimizations, and semi-empirical PM3 level and density functional theory B3LYP/6-31G* level calculations within UHF formalism. Calculations have been performed with different spin configurations for the neutral systems.

  13. Structure and Organization of Coat Proteins in the COPll Cage

    SciTech Connect

    Fath,S.; Mancias, J.; Bi, X.; Goldberg, J.

    2007-01-01

    COPII-coated vesicles export newly synthesized proteins from the endoplasmic reticulum. The COPII coat consists of the Sec23/24-Sar1 complex that selects cargo and the Sec13/31 assembly unit that can polymerize into an octahedral cage and deform the membrane into a bud. Crystallographic analysis of the assembly unit reveals a 28 nm long rod comprising a central {alpha}-solenoid dimer capped by two {beta}-propeller domains at each end. We construct a molecular model of the COPII cage by fitting Sec13/31 crystal structures into a recently determined electron microscopy density map. The vertex geometry involves four copies of the Sec31 {beta}-propeller that converge through their axial ends; there is no interdigitation of assembly units of the kind seen in clathrin cages. We also propose that the assembly unit has a central hinge -- an arrangement of interlocked {alpha}-solenoids -- about which it can bend to adapt to cages of variable curvature.

  14. Massive acetabular bone loss: Limits of trabecular metal cages

    PubMed Central

    Villanueva-Martínez, Manuel; Ríos-Luna, Antonio; Diaz-Mauriño, Juán

    2011-01-01

    Massive acetabular bone loss (more than 50% of the acetabular area) can result in insufficient native bone for stable fixation and long-term bone ingrowth of conventional porous cups. The development of trabecular metal cages with osteoconductive properties may allow a more biological and versatile approach that will help restore bone loss, thus reducing the frequency of implant failure in the short-to-medium term. We report a case of massive bone loss affecting the dome of the acetabulum and the ilium, which was treated with a trabecular metal cage and particulate allograft. Although the trabecular metal components had no intrinsic stability, they did enhance osseointegration and incorporation of a non-impacted particulate graft, thus preventing failure of the reconstruction. The minimum 50% contact area between the native bone and the cup required for osseointegration with the use of porous cups may not hold for new trabecular metal cups, thus reducing the need for antiprotrusio cages. The osteoconductive properties of trabecular metal enhanced allograft incorportation and iliac bone rebuilding without the need to fill the defect with multiple wedges nor protect the reconstruction with an antiprotrusio cage. PMID:21221229

  15. Caged polyprenylated xanthones from the resin of Garcinia hanburyi.

    PubMed

    Chen, Yu; He, Shiwen; Tang, Chu; Li, Jun; Yang, Guangzhong

    2016-03-01

    Five new caged polyprenylated xanthones (1a, 2a, 3, 10a and 10b), and 12 known related compounds were isolated from the resin of Garcinia hanburyi. Their structures were elucidated by detailed spectroscopic analyses and their α-glucosidase inhibitory activities were investigated in vitro. Most of xanthones showed modest inhibitory activity against α-glucosidase. PMID:26688377

  16. MOIRAI: a compact workflow system for CAGE analysis

    PubMed Central

    2014-01-01

    Background Cap analysis of gene expression (CAGE) is a sequencing based technology to capture the 5’ ends of RNAs in a biological sample. After mapping, a CAGE peak on the genome indicates the position of an active transcriptional start site (TSS) and the number of reads correspond to its expression level. CAGE is prominently used in both the FANTOM and ENCODE project but presently there is no software package to perform the essential data processing steps. Results Here we describe MOIRAI, a compact yet flexible workflow system designed to carry out the main steps in data processing and analysis of CAGE data. MOIRAI has a graphical interface allowing wet-lab researchers to create, modify and run analysis workflows. Embedded within the workflows are graphical quality control indicators allowing users assess data quality and to quickly spot potential problems. We will describe three main workflows allowing users to map, annotate and perform an expression analysis over multiple samples. Conclusions Due to the many built in quality control features MOIRAI is especially suitable to support the development of new sequencing based protocols. Availiability The MOIRAI source code is freely available at http://sourceforge.net/projects/moirai/. PMID:24884663

  17. EFFECTS OF CAGING DENSITY ON PITUITARY AND TESTICLE RELATED RESPONSES

    EPA Science Inventory

    Effects of caging density on pituitary and testicle related responses

    A significant negative correlation between the incidence of testicular interstitial cell tumors (ICT) and of pituitary tumors (PT) in control male F344 rats is reported associated with the number of ani...

  18. Pathogen Prevalence From Traditional Cage and Free Range Production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Overview: A study was conducted to determine if differences in pathogen prevalence occurred between a sister flock of conventional cage and free range laying hens. Both environmental and egg microbiology was monitored throughout 20 – 79 weeks of age. Salmonella, Campylobacter, and Listeria preval...

  19. Normal and abnormal spine and thoracic cage development

    PubMed Central

    Canavese, Federico; Dimeglio, Alain

    2013-01-01

    Development of the spine and thoracic cage consists of a complex series of events involving multiple metabolic processes, genes and signaling pathways. During growth, complex phenomena occur in rapid succession. This succession of events, this establishment of elements, is programmed according to a hierarchy. These events are well synchronized to maintain harmonious limb, spine and thoracic cage relationships, as growth in the various body segments does not occur simultaneously at the same magnitude or rate. In most severe cases of untreated progressive early-onset spinal deformities, respiratory insufficiency and pulmonary and cardiac hypertension (cor pulmonale), which characterize thoracic insufficiency syndrome (TIS), can develop, sometimes leading to death. TIS is the inability of the thorax to ensure normal breathing. This clinical condition can be linked to costo-vertebral malformations (e.g., fused ribs, hemivertebrae, congenital bars), neuromuscular diseases (e.g., expiratory congenital hypotonia), Jeune or Jarcho-Levin syndromes or to 50% to 75% fusion of the thoracic spine before seven years of age. Complex spinal deformities alter normal growth plate development, and vertebral bodies become progressively distorted, perpetuating the disorder. Therefore, many scoliotic deformities can become growth plate disorders over time. This review aims to provide a comprehensive review of how spinal deformities can affect normal spine and thoracic cage growth. Previous conceptualizations are integrated with more recent scientific data to provide a better understanding of both normal and abnormal spine and thoracic cage growth. PMID:24147251

  20. 3. SHOP AREA. Looking west into storage cage from near ...

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

    3. SHOP AREA. Looking west into storage cage from near northeast corner of room. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A Terminal Room, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA

  1. Three-dimensional protonic conductivity in porous organic cage solids.

    PubMed

    Liu, Ming; Chen, Linjiang; Lewis, Scott; Chong, Samantha Y; Little, Marc A; Hasell, Tom; Aldous, Iain M; Brown, Craig M; Smith, Martin W; Morrison, Carole A; Hardwick, Laurence J; Cooper, Andrew I

    2016-01-01

    Proton conduction is a fundamental process in biology and in devices such as proton exchange membrane fuel cells. To maximize proton conduction, three-dimensional conduction pathways are preferred over one-dimensional pathways, which prevent conduction in two dimensions. Many crystalline porous solids to date show one-dimensional proton conduction. Here we report porous molecular cages with proton conductivities (up to 10(-3) S cm(-1) at high relative humidity) that compete with extended metal-organic frameworks. The structure of the organic cage imposes a conduction pathway that is necessarily three-dimensional. The cage molecules also promote proton transfer by confining the water molecules while being sufficiently flexible to allow hydrogen bond reorganization. The proton conduction is explained at the molecular level through a combination of proton conductivity measurements, crystallography, molecular simulations and quasi-elastic neutron scattering. These results provide a starting point for high-temperature, anhydrous proton conductors through inclusion of guests other than water in the cage pores. PMID:27619230

  2. Correction of spray concentration and bioassay cage penetration data

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field trials were conducted to demonstrate the need for correcting sampled spray concentration data for sampler collection efficiencies and estimated spray exposure levels in mosquito bioassays for cage interference effects. A large spray block was targeted with aerial spray treatments of etofenpro...

  3. Synthesis of Novel Chiral, Cage-Annulated Macrocycles

    SciTech Connect

    Marchand, Alan O.' Takhi, Mohamed; Kumar, Satish; Krishnudu, Kasireddy; Ganguly, Bishwajit

    2001-07-01

    Methods used to prepare several new cage-annulated chiral macrocycles are reported. These novel host systems were synthesized either by incorporating an optically active monosaccharide derivative or a tartaric acid derivative into each crown ether to provide the source of chirality.

  4. Assessment of density in enriched colony cages: Egg quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enriched colony cage production systems are becoming more prevalent in the US. A study was undertaken to determine the impact of housing density on hen health, well-being, egg production and quality. Six densities were examined with 8 housing replicates per density. Egg quality was assessed at hen a...

  5. COATING ALTERNATIVES GUIDE (CAGE) FOR METAL PARTS AND PRODUCTS PAINTING

    EPA Science Inventory

    The paper discusses the initial development of a Coating Alternatives Guide (CAGE) for metal parts and products painting. t is an innovative technology transfer approach that provides a tool to improve technology diffusion and assistance. t will provide vital, user-accessible inf...

  6. Aortic valve patch closure: an alternative to replacement with HeartMate LVAS insertion.

    PubMed

    Savage, E B; d'Amato, T A; Magovern, J A

    1999-09-01

    A PTFE patch sewn to the aortic valve and annulus, to occlude the ventriculoaortic junction is used to successfully correct aortic insufficiency with HeartMate (LVAS) insertion. This represents an inexpensive alternative to aortic valve replacement for aortic insufficiency or the presence of a mechanical aortic valve. PMID:10554859

  7. Coronary Ostial Stenosis after Aortic Valve Replacement

    PubMed Central

    Ziakas, Antonios G.; Economou, Fotios I.; Charokopos, Nicholas A.; Pitsis, Antonios A.; Parharidou, Despina G.; Papadopoulos, Thomas I.; Parharidis, Georgios E.

    2010-01-01

    Coronary ostial stenosis is a rare but potentially serious sequela after aortic valve replacement. It occurs in the left main or right coronary artery after 1% to 5% of aortic valve replacement procedures. The clinical symptoms are usually severe and may appear from 1 to 6 months postoperatively. Although the typical treatment is coronary artery bypass grafting, patients have been successfully treated by means of percutaneous coronary intervention. Herein, we present the cases of 2 patients in whom coronary ostial stenosis developed after aortic valve replacement. In the 1st case, a 72-year-old man underwent aortic valve replacement and bypass grafting of the saphenous vein to the left anterior descending coronary artery. Six months later, he experienced a non-ST-segment-elevation myocardial infarction. Coronary angiography revealed a critical stenosis of the right coronary artery ostium. In the 2nd case, a 78-year-old woman underwent aortic valve replacement and grafting of the saphenous vein to an occluded right coronary artery. Four months later, she experienced unstable angina. Coronary angiography showed a critical left main coronary artery ostial stenosis and occlusion of the right coronary artery venous graft. In each patient, we performed percutaneous coronary intervention and deployed a drug-eluting stent. Both patients were asymptomatic on 6-to 12-month follow-up. We attribute the coronary ostial stenosis to the selective ostial administration of cardioplegic solution during surgery. We conclude that retrograde administration of cardioplegic solution through the coronary sinus may reduce the incidence of postoperative coronary ostial stenosis, and that stenting may be an efficient treatment option. PMID:20844624

  8. Spatiotemporal complexity of the aortic sinus vortex

    NASA Astrophysics Data System (ADS)

    Moore, Brandon; Dasi, Lakshmi Prasad

    2014-07-01

    The aortic sinus vortex is a classical flow structure of significant importance to aortic valve dynamics and the initiation and progression of calcific aortic valve disease. We characterize the spatiotemporal characteristics of aortic sinus vortex dynamics in relation to the viscosity of blood analog solution as well as heart rate. High-resolution time-resolved (2 kHz) particle image velocimetry was conducted to capture 2D particle streak videos and 2D instantaneous velocity and streamlines along the sinus midplane using a physiological but rigid aorta model fitted with a porcine bioprosthetic heart valve. Blood analog fluids used include a water-glycerin mixture and saline to elucidate the sensitivity of vortex dynamics to viscosity. Experiments were conducted to record 10 heart beats for each combination of blood analog and heart rate condition. Results show that the topological characteristics of the velocity field vary in timescales as revealed using time bin-averaged vectors and corresponding instantaneous streamlines. There exist small timescale vortices and a large timescale main vortex. A key flow structure observed is the counter vortex at the upstream end of the sinus adjacent to the base (lower half) of the leaflet. The spatiotemporal complexity of vortex dynamics is shown to be profoundly influenced by strong leaflet flutter during systole with a peak frequency of 200 Hz and peak amplitude of 4 mm observed in the saline case. While fluid viscosity influences the length and timescales as well as the introduction of leaflet flutter, heart rate influences the formation of counter vortex at the upstream end of the sinus. Higher heart rates are shown to reduce the strength of the counter vortex that can greatly influence the directionality and strength of shear stresses along the base of the leaflet. This study demonstrates the impact of heart rate and blood analog viscosity on aortic sinus hemodynamics.

  9. Transcatheter aortic valve implantation today and tomorrow.

    PubMed

    Wenaweser, Peter; Praz, Fabien; Stortecky, Stefan

    2016-01-01

    Aortic stenosis is the most common valvular heart disease in Western industrial countries (including Switzerland) with a prevalence of about 5% in the population aged 75 and over. If left untreated, symptomatic patients have a rate of death of more than 50% within 2 years. As a result of age and elevated surgical risk, an important proportion of elderly patients are not referred to surgery. Thus, the introduction of transcatheter aortic valve implantation (TAVI) in 2002 has initiated a paradigm shift in the treatment of patients with symptomatic, severe aortic stenosis. The early technical and procedural success of this minimal invasive treatment in high-risk patients has promoted further innovation and development of transcatheter heart valve (THV) systems during the last 13 years. Downsizing of the delivery catheters along with technical improvements aiming to reduce postprocedural paravalvular regurgitation have resulted in a significant reduction in mortality. As a consequence, TAVI is nowadays established as safe and effective treatment for selected inoperable and high-risk patients. Ongoing studies are investigating the outcome of intermediate risk patients allocated to either surgical aortic valve replacement (SAVR) or TAVI. Despite these advancements, some specific areas of concern still require attention and need further investigations including conduction disturbances, valve degeneration and antithrombotic management. Although the off-label use of TAVI devices in the mitral, tricuspid or pulmonary position has recently developed, important limitations still apply and careful patient selection remains crucial. This review aims to summarise the available clinical evidence of transcatheter aortic valve treatment during the last 13 years and to provide a glimpse of future technologies. PMID:26999727

  10. 48 CFR 204.7206 - Using CAGE codes to identify agents and brokers.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Using CAGE codes to... 204.7206 Using CAGE codes to identify agents and brokers. Authorized agents and brokers are entities and, as such, may be assigned CAGE codes for identification and processing purposes. (a) A single...

  11. 25 CFR 542.14 - What are the minimum internal control standards for the cage?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... cage? 542.14 Section 542.14 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR HUMAN... the cage? (a) Computer applications. For any computer applications utilized, alternate documentation... checks, or counter checks are cashed at the cage, the Tribal gaming regulatory authority, or the...

  12. 25 CFR 542.14 - What are the minimum internal control standards for the cage?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... cage? 542.14 Section 542.14 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR HUMAN... the cage? (a) Computer applications. For any computer applications utilized, alternate documentation... checks, or counter checks are cashed at the cage, the Tribal gaming regulatory authority, or the...

  13. 48 CFR 204.7206 - Using CAGE codes to identify agents and brokers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Using CAGE codes to... 204.7206 Using CAGE codes to identify agents and brokers. Authorized agents and brokers are entities and, as such, may be assigned CAGE codes for identification and processing purposes. (a) A single...

  14. 48 CFR 204.7206 - Using CAGE codes to identify agents and brokers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Using CAGE codes to... 204.7206 Using CAGE codes to identify agents and brokers. Authorized agents and brokers are entities and, as such, may be assigned CAGE codes for identification and processing purposes. (a) A single...

  15. 25 CFR 542.14 - What are the minimum internal control standards for the cage?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... cage? 542.14 Section 542.14 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR HUMAN... the cage? (a) Computer applications. For any computer applications utilized, alternate documentation... checks, or counter checks are cashed at the cage, the Tribal gaming regulatory authority, or the...

  16. 48 CFR 4.1803 - Verifying CAGE codes prior to award.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 1 2014-10-01 2014-10-01 false Verifying CAGE codes prior... GENERAL ADMINISTRATIVE MATTERS Commercial and Government Entity Code 4.1803 Verifying CAGE codes prior to award. (a) Contracting officers shall verify the offeror's CAGE code by reviewing the...

  17. 48 CFR 204.7206 - Using CAGE codes to identify agents and brokers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Using CAGE codes to... 204.7206 Using CAGE codes to identify agents and brokers. Authorized agents and brokers are entities and, as such, may be assigned CAGE codes for identification and processing purposes. (a) A single...

  18. 25 CFR 542.14 - What are the minimum internal control standards for the cage?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... cage? 542.14 Section 542.14 Indians NATIONAL INDIAN GAMING COMMISSION, DEPARTMENT OF THE INTERIOR HUMAN... the cage? (a) Computer applications. For any computer applications utilized, alternate documentation... checks, or counter checks are cashed at the cage, the Tribal gaming regulatory authority, or the...

  19. 48 CFR 204.7206 - Using CAGE codes to identify agents and brokers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Using CAGE codes to... 204.7206 Using CAGE codes to identify agents and brokers. Authorized agents and brokers are entities and, as such, may be assigned CAGE codes for identification and processing purposes. (a) A single...

  20. A Reliability Induction and Reliability Generalization Study of the Cage Questionnaire

    ERIC Educational Resources Information Center

    Shields, Alan L.; Caruso, John C.

    2004-01-01

    The CAGE is a commonly used alcohol screening instrument. Although considerable work has been done on the validity of CAGE scores, relatively little information is available on their reliability. Reliability induction and generalization studies were performed for the CAGE. Of the 259 studies available for analysis, only 19 (7.3%) contained…

  1. The effect of perches installed in conventional cages on White Leghorn pullets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Enrichments for laying cages are receiving increasing attention by egg producers as a means of meeting the behavioral needs of laying hens. Pullet cage enrichments have received less attention and study. Adapting pullets to perches prior to placement in enriched laying cages may offer health and wel...

  2. Selective occupancy of methane by cage symmetry in TBAB ionic clathrate hydrate.

    PubMed

    Muromachi, Sanehiro; Udachin, Konstantin A; Alavi, Saman; Ohmura, Ryo; Ripmeester, John A

    2016-04-12

    Methane trapped in the two distinct dodecahedral cages of the ionic clathrate hydrate of TBAB was studied by single crystal XRD and MD simulation. The relative CH4 occupancies over the cage types were opposite to those of CO2, which illustrates the interplay between the cage symmetry and guest shape and dynamics, and thus the gas selectivity. PMID:27030139

  3. Cage Versus Noncage Laying-Hen Housings: Worker Respiratory Health.

    PubMed

    Mitchell, Diane; Arteaga, Veronica; Armitage, Tracey; Mitloehner, Frank; Tancredi, Daniel; Kenyon, Nicholas; Schenker, Marc

    2015-01-01

    The objective of this study was to compare respiratory health of poultry workers in conventional cage, enriched cage and aviary layer housing on a single commercial facility, motivated by changing requirements for humane housing of hens. Three workers were randomly assigned daily, one to each of conventional cage, enriched cage, and aviary housing in a crossover repeated-measures design for three observation periods (for a total of 123 worker-days, eight different workers). Workers' exposure to particles were assessed (Arteaga et al. J Agromedicine. 2015;20:this issue) and spirometry, exhaled nitric oxide, respiratory symptoms, and questionnaires were conducted pre- and post-shift. Personal exposures to particles and endotoxin were significantly higher in the aviary than the other housings (Arteaga et al., 2015). The use of respiratory protection was high; the median usage was 70% of the shift. Mixed-effects multivariate regression models of respiratory cross-shift changes were marginally significant, but the aviary system consistently posted the highest decrements for forced expiratory volume in 1 and 6 seconds (FEV1 and FEV6) compared with the enriched or conventional housing. The adjusted mean difference in FEV1 aviary - enriched cage housing was -47 mL/s, 95% confidence interval (CI): (-99 to 4.9), P = .07. Similarly, for FEV6, aviary - conventional housing adjusted mean difference was -52.9 mL/6 s, 95% CI: (-108 to 2.4), P = .06. Workers adopting greater than median use of respiratory protection were less likely to exhibit negative cross-shift pulmonary function changes. Although aviary housing exposed workers to significantly higher respiratory exposures, cross-shift pulmonary function changes did not differ significantly between houses. Higher levels of mask use were protective; poultry workers should wear respiratory protection as appropriate to avoid health decrements. PMID:26237715

  4. Cage Clusters of Gold and Tin: Golden Buckyballs and Stannaspherene

    NASA Astrophysics Data System (ADS)

    Wang, Lai-Sheng

    2008-03-01

    Photoelectron spectroscopy (PES) yields direct electronic structure information for size-selected clusters. Combining PES with theoretical calculations has become an effective approach to obtain structural information for small and medium-sized clusters. We present recent discoveries of two classes of cage clusters in gold and tin. Negatively charged gold clusters (Aun^-) have been shown to exhibit a remarkable structural diversity from 2D structures for n = 4-12 and the pyramidal structure for n = 20. Using PES and DFT calculations, we have found that gold clusters with n = 16-18 possess unprecedented hollow cage structures. We have been able to successfully dope a variety of transition-metal atoms into the empty spaces in the golden cages, confirming their structural robustness, as well as demonstrating chemical tuning of their electronic, magnetic, and catalytic properties. Unlike carbon, the heavier congeners of the group 14 elements are not known to form hollow cage structures similar to the fullerenes. In PES studies of tin clusters, we noted that the spectrum of Sn12^- is distinctly different from that of its neighbors or its Si/Ge counterpart. This observation led to our discovery of a highly symmetric and stable icosahedral Sn12^2- cage, for which we coined a name ``stannaspherene'' to describe its high symmetry and spherical pi bonding. We have also shown that all transition metals including the f-block elements can be doped inside Sn12^2- to form a whole class of endohedral stannaspherenes, which may be used as potential building blocks for new cluster-assembled materials. In a preliminary experiment to synthesize stannaspherene in the bulk, a new cluster, Pd2@Sn18^4-, was crystallized and characterized, suggesting all stannaspherene and endohedral stannasphernes may be fabricated in the bulk under suitable conditions.

  5. Corpectomy cage subsidence with rectangular versus round endcaps.

    PubMed

    Deukmedjian, Armen R; Manwaring, Jotham; Le, Tien V; Turner, Alexander W L; Uribe, Juan S

    2014-09-01

    Corpectomy cages with rectangular endcaps utilize the stronger peripheral part of the endplate, potentially decreasing subsidence risk. The authors evaluated cage subsidence during cyclic biomechanical testing, comparing rectangular versus round endcaps. Fourteen cadaveric spinal segments (T12-L2) were dissected and potted at T12 and L2, then assigned to a rectangular (n=7) or round (n=7) endcap group. An L1 corpectomy was performed and under uniform conditions a cage/plate construct was cyclically tested in a servo-hydraulic frame with increasing load magnitude. Testing was terminated if the test machine actuator displacement exceeded 6mm, or the specimen completed cyclic loading at 2400 N. Number of cycles, compressive force and force-cycles product at test completion were all greater in the rectangular endcap group compared with the round endcap group (cycles: 3027 versus 2092 cycles; force: 1943 N versus 1533 N; force-cycles product: 6162kN·cycles versus 3973 kN·cycles), however these differences were not statistically significant (p ⩾ 0.076). After normalizing for individual specimen bone mineral density, the same measures increased to a greater extent with the rectangular endcaps (cycles: 3014 versus 1855 cycles; force: 1944 N versus 1444 N; force-cycles product: 6040 kN·cycles versus 2980 kN·cycles), and all differences were significant (p⩽0.030). The rectangular endcap expandable corpectomy cage displayed increased resistance to subsidence over the round endcap cage under cyclic loading as demonstrated by the larger number of cycles, maximum load and force-cycles product at test completion. This suggests rectangular endcaps will be less susceptible to subsidence than the round endcap design. PMID:24831343

  6. Flash photolysis of caged compounds in Limulus ventral photoreceptors

    PubMed Central

    1992-01-01

    Rapid concentration jumps of Ins(1,4,5)P3 or ATP were made inside Limulus ventral photoreceptors by flash photolysis of the parent caged compounds. In intact ventral photoreceptors, the photolysis flash evokes a maximum amplitude light-activated current; therefore, a procedure was developed for uncoupling phototransduction by blocking two of the initial reactions in the cascade, rhodopsin excitation and G protein activation. Rhodopsin was inactivated by exposure to hydroxylamine and bright light. This procedure abolished the early receptor potential and reduced the quantum efficiency by 325 +/- 90- fold (mean +/- SD). G protein activation was blocked by injection of guanosine-5'-O-(2-thiodiphosphate) (GDP beta S). GDP beta S injection reduced the quantum efficiency by 1,881 +/- 1,153-fold (mean +/- SD). Together hydroxylamine exposure and GDP beta S injection reduced the quantum efficiency by 870,000 +/- 650,000-fold (mean +/- SD). After the combined treatment, photoreceptors produced quantum bumps to light that was approximately 10(6) times brighter than the intensity that produced quantum bumps before treatment. Experiments were performed with caged compounds injected into photoreceptors in which phototransduction was largely uncoupled. Photolysis of one compound, myo-inositol 1,4,5- triphosphate P4(5)-1-(2-nitrophenyl)ethyl ester (caged IP3), increased the voltage clamp current in response to the flashlamp by more than twofold without changing the latency of the response. The effect was not seen with photolysis of either adenosine-5'-triphosphate P3-1-(2- nitrophenyl)ethyl ester (caged ATP) or caged IP3 in cells preloaded with either heparin or (1,2-bis-(o-amino-phenoxy)ethane-N-N-N'-N' tetraacetic acid tetrapotassium salt (BAPTA). The results suggest that photoreleased IP3 releases calcium ions from intracellular stores and the resulting increase in [Ca2+]i enhances the amplification of the phototransduction cascade. PMID:1431805

  7. Social Communication in Mice – Are There Optimal Cage Conditions?

    PubMed Central

    Ferhat, Allain-Thibeault; Le Sourd, Anne-Marie; de Chaumont, Fabrice; Olivo-Marin, Jean-Christophe; Bourgeron, Thomas; Ey, Elodie

    2015-01-01

    Social communication is heavily affected in patients with neuropsychiatric disorders. Accordingly, mouse models designed to study the mechanisms leading to these disorders are tested for this phenotypic trait. Test conditions vary between different models, and the effect of these test conditions on the quantity and quality of social interactions and ultrasonic communication is unknown. The present study examines to which extent the habituation time to the test cage as well as the shape / size of the cage influence social communication in freely interacting mice. We tested 8 pairs of male mice in free dyadic social interactions, with two habituation times (20 min and 30 min) and three cage formats (rectangle, round, square). We tested the effect of these conditions on the different types of social contacts, approach-escape sequences, follow behavior, and the time each animal spent in the vision field of the other one, as well as on the emission of ultrasonic vocalizations and their contexts of emission. We provide for the first time an integrated analysis of the social interaction behavior and ultrasonic vocalizations. Surprisingly, we did not highlight any significant effect of habituation time and cage shape / size on the behavioral events examined. There was only a slight increase of social interactions with the longer habituation time in the round cage. Remarkably, we also showed that vocalizations were emitted during specific behavioral sequences especially during close contact or approach behaviors. The present study provides a protocol reliably eliciting social contacts and ultrasonic vocalizations in adult male mice. This protocol is therefore well adapted for standardized investigation of social interactions in mouse models of neuropsychiatric disorders. PMID:25806942

  8. Action of the diaphragm on the rib cage.

    PubMed

    Troyer, André De; Wilson, Theodore A

    2016-08-01

    When the diaphragm contracts, pleural pressure falls, exerting a caudal and inward force on the entire rib cage. However, the diaphragm also exerts forces in the cranial and outward direction on the lower ribs. One of these forces, the "insertional force," is applied by the muscle at its attachments to the lower ribs. The second, the "appositional force," is due to the transmission of abdominal pressure to the lower rib cage in the zone of apposition. In the control condition at functional residual capacity, the effects of these two forces on the lower ribs are nearly equal and outweigh the effect of pleural pressure, whereas for the upper ribs, the effect of pleural pressure is greater. The balance between these effects, however, may be altered. When the abdomen is given a mechanical support, the insertional and appositional forces are increased, so that the muscle produces a larger expansion of the lower rib cage and, with it, a smaller retraction of the upper rib cage. In contrast, at higher lung volumes the zone of apposition is decreased, and pleural pressure is the dominant force on the lower ribs as well. Consequently, although the force exerted by the diaphragm on these ribs remains inspiratory, rib displacement is reversed into a caudal-inward displacement. This mechanism likely explains the inspiratory retraction of the lateral walls of the lower rib cage observed in many subjects with chronic obstructive pulmonary disease (Hoover's sign). These observations support the use of a three-compartment, rather than a two-compartment, model to describe chest wall mechanics. PMID:27283911

  9. Social communication in mice--are there optimal cage conditions?

    PubMed

    Ferhat, Allain-Thibeault; Le Sourd, Anne-Marie; de Chaumont, Fabrice; Olivo-Marin, Jean-Christophe; Bourgeron, Thomas; Ey, Elodie

    2015-01-01

    Social communication is heavily affected in patients with neuropsychiatric disorders. Accordingly, mouse models designed to study the mechanisms leading to these disorders are tested for this phenotypic trait. Test conditions vary between different models, and the effect of these test conditions on the quantity and quality of social interactions and ultrasonic communication is unknown. The present study examines to which extent the habituation time to the test cage as well as the shape/size of the cage influence social communication in freely interacting mice. We tested 8 pairs of male mice in free dyadic social interactions, with two habituation times (20 min and 30 min) and three cage formats (rectangle, round, square). We tested the effect of these conditions on the different types of social contacts, approach-escape sequences, follow behavior, and the time each animal spent in the vision field of the other one, as well as on the emission of ultrasonic vocalizations and their contexts of emission. We provide for the first time an integrated analysis of the social interaction behavior and ultrasonic vocalizations. Surprisingly, we did not highlight any significant effect of habituation time and cage shape/size on the behavioral events examined. There was only a slight increase of social interactions with the longer habituation time in the round cage. Remarkably, we also showed that vocalizations were emitted during specific behavioral sequences especially during close contact or approach behaviors. The present study provides a protocol reliably eliciting social contacts and ultrasonic vocalizations in adult male mice. This protocol is therefore well adapted for standardized investigation of social interactions in mouse models of neuropsychiatric disorders. PMID:25806942

  10. Mathematical modeling of aortic valve dynamics during systole.

    PubMed

    Aboelkassem, Yasser; Savic, Dragana; Campbell, Stuart G

    2015-01-21

    We have derived a mathematical model describing aortic valve dynamics and blood flow during systole. The model presents a realistic coupling between aortic valve dynamics, sinus vortex local pressure, and variations in the systemic vascular resistance. The coupling is introduced by using Hill׳s classical semi-spherical vortex model and an aortic pressure-area compliance constitutive relationship. The effects of introducing aortic sinus eddy vortices and variable systemic vascular resistance on overall valve opening-closing dynamics, left ventricular pressure, aortic pressure, blood flow rate, and aortic orifice area are examined. In addition, the strength of the sinus vortex is coupled explicitly to the valve opening angle, and implicitly to the aortic orifice area in order to predict how vortex strength varies during the four descriptive phases of aortic valve motion (fast-opening, fully-opening, slow-closing, and fast-closing). Our results compare favorably with experimental observations and the model reproduces well-known phenomena corresponding to aortic valve function such as the dicrotic notch and retrograde flow at end systole. By invoking a more complete set of physical phenomena, this new model will enable representation of pathophysiological conditions such as aortic valve stenosis or insufficiency, making it possible to predict their integrated effects on cardiac load and systemic hemodynamics. PMID:25451522

  11. Computer-aided design of the human aortic root.

    PubMed

    Ovcharenko, E A; Klyshnikov, K U; Vlad, A R; Sizova, I N; Kokov, A N; Nushtaev, D V; Yuzhalin, A E; Zhuravleva, I U

    2014-11-01

    The development of computer-based 3D models of the aortic root is one of the most important problems in constructing the prostheses for transcatheter aortic valve implantation. In the current study, we analyzed data from 117 patients with and without aortic valve disease and computed tomography data from 20 patients without aortic valvular diseases in order to estimate the average values of the diameter of the aortic annulus and other aortic root parameters. Based on these data, we developed a 3D model of human aortic root with unique geometry. Furthermore, in this study we show that by applying different material properties to the aortic annulus zone in our model, we can significantly improve the quality of the results of finite element analysis. To summarize, here we present four 3D models of human aortic root with unique geometry based on computational analysis of ECHO and CT data. We suggest that our models can be utilized for the development of better prostheses for transcatheter aortic valve implantation. PMID:25238567

  12. Intra-cage dynamics of molecular hydrogen confined in cages of two different dimensions of clathrate hydrates

    PubMed Central

    Russina, Margarita; Kemner, Ewout; Mezei, Ferenc

    2016-01-01

    In porous materials the molecular confinement is often realized by means of weak Van der Waals interactions between the molecule and the pore surface. The understanding of the mechanism of such interactions is important for a number of applications. In order to establish the role of the confinement size we have studied the microscopic dynamics of molecular hydrogen stored in the nanocages of clathrate hydrates of two different dimensions. We have found that by varying the size of the pore the diffusive mobility of confined hydrogen can be modified in both directions, i.e. reduced or enhanced compared to that in the bulk solid at the same temperatures. In the small cages with a mean crystallographic radius of 3.95 Å the confinement reduces diffusive mobility by orders of magnitude. In contrast, in large cages with a mean radius of 4.75 Å hydrogen molecules displays diffusive jump motion between different equilibrium sites inside the cages, visible at temperatures where bulk H2 is solid. The localization of H2 molecules observed in small cages can promote improved functional properties valuable for hydrogen storage applications. PMID:27270444

  13. Intra-cage dynamics of molecular hydrogen confined in cages of two different dimensions of clathrate hydrates.

    PubMed

    Russina, Margarita; Kemner, Ewout; Mezei, Ferenc

    2016-01-01

    In porous materials the molecular confinement is often realized by means of weak Van der Waals interactions between the molecule and the pore surface. The understanding of the mechanism of such interactions is important for a number of applications. In order to establish the role of the confinement size we have studied the microscopic dynamics of molecular hydrogen stored in the nanocages of clathrate hydrates of two different dimensions. We have found that by varying the size of the pore the diffusive mobility of confined hydrogen can be modified in both directions, i.e. reduced or enhanced compared to that in the bulk solid at the same temperatures. In the small cages with a mean crystallographic radius of 3.95 Å the confinement reduces diffusive mobility by orders of magnitude. In contrast, in large cages with a mean radius of 4.75 Å hydrogen molecules displays diffusive jump motion between different equilibrium sites inside the cages, visible at temperatures where bulk H2 is solid. The localization of H2 molecules observed in small cages can promote improved functional properties valuable for hydrogen storage applications. PMID:27270444

  14. Impaired fear extinction as displayed by serotonin transporter knockout rats housed in open cages is disrupted by IVC cage housing.

    PubMed

    Shan, Ling; Schipper, Pieter; Nonkes, Lourens J P; Homberg, Judith R

    2014-01-01

    Anxiety disorders are influenced by both environmental and genetic factors. A well-known example for gene x environment interactions in psychiatry is the low activity (s) allelic variant of the serotonin transporter (5-HTT) promoter polymorphism (5-HTTLPR) that in the context of stress increases risk for depression and post-traumatic stress disorder (PTSD). Previously, we observed robust anxiety-related phenotypes, such as an impairment in fear extinction, in 5-HTT knockout (5-HTT-/-) versus wild-type (5-HTT+/+) rats housed in open cages. Recently, housing conditions were changed from open cages to individually ventilated cages (IVC), which are associated with a high ventilation fold and noise. This switch in housing conditions prompted an unplanned 5-HTT gene x environment interaction study in our rats. The current study shows that lifetime stress by means of IVC cage housing abolished genotype differences in fear extinction between 5-HTT-/- and 5-HTT+/+ rats. Although this effect was not attributed specifically to either the 5-HTT+/+ or the 5-HTT-/- genotype, the findings are in agreement with the modulatory role of serotonin in the processing of environmental stimuli. Our findings also underline the possibility that housing conditions confound the interpretation of anxiety-related behaviours in rodents. PMID:24658187

  15. Potential for horizontal transmission of Salmonella & Campylobacter among caged & cage-free laying hens pp. 41-44.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With an increasing number of table egg producers transitioning to cage-free housing systems, it is important to determine what effects housing systems may have on the spread of Salmonella and Campylobacter among hens. In each of five sequential trials, hens were inoculated with marker strains of Sa...

  16. Multiplexed Analysis of Cage and Cage Free Chicken Egg Fatty Acids Using Stable Isotope Labeling and Mass Spectrometry

    PubMed Central

    Torde, Richard G.; Therrien, Andrew J.; Shortreed, Michael R.; Smith, Lloyd M.; Lamos, Shane M.

    2014-01-01

    Binary stable isotope labeling couple with LC-ESI-MS has been used as a powerful non-targeted approach for the relative quantification of lipids, amino acids, and many other important metabolite classes. A multiplexed approach using three or more isotopic labeling reagents greatly reduces analytical run-time while maintaining excellent sensitivity and reproducibility. Three isotopic cholamine labeling reagents have been developed to take advantage of the pre-ionized character of cholamine, for ESI, and the ease by which stable isotopes can be incorporated into the cholamine structure. These three cholamine labeling reagents have been used to relatively quantify three fatty acid samples simultaneously. The quantification resulted in the observation of 12 fatty acids that had an average absolute error of 0.9% and an average coefficient of variation of 6.1%. Caged versus cage-free isotope labeling experiments showed that cage-free eggs have an increased level of omega-3 fatty acids as compared to caged eggs. This multiplexed fatty acid analysis provides an inexpensive and expedited tool for broad-based lipid profiling that will further aid discoveries in the mechanisms of fatty acid action in cells. PMID:24317525

  17. Multiplexed analysis of cage and cage free chicken egg fatty acids using stable isotope labeling and mass spectrometry.

    PubMed

    Torde, Richard G; Therrien, Andrew J; Shortreed, Michael R; Smith, Lloyd M; Lamos, Shane M

    2013-01-01

    Binary stable isotope labeling couple with LC-ESI-MS has been used as a powerful non-targeted approach for the relative quantification of lipids, amino acids, and many other important metabolite classes. A multiplexed approach using three or more isotopic labeling reagents greatly reduces analytical run-time while maintaining excellent sensitivity and reproducibility. Three isotopic cholamine labeling reagents have been developed to take advantage of the pre-ionized character of cholamine, for ESI, and the ease by which stable isotopes can be incorporated into the cholamine structure. These three cholamine labeling reagents have been used to relatively quantify three fatty acid samples simultaneously. The quantification resulted in the observation of 12 fatty acids that had an average absolute error of 0.9% and an average coefficient of variation of 6.1%. Caged versus cage-free isotope labeling experiments showed that cage-free eggs have an increased level of omega-3 fatty acids as compared to caged eggs. This multiplexed fatty acid analysis provides an inexpensive and expedited tool for broad-based lipid profiling that will further aid discoveries in the mechanisms of fatty acid action in cells. PMID:24317525

  18. Intra-cage dynamics of molecular hydrogen confined in cages of two different dimensions of clathrate hydrates

    NASA Astrophysics Data System (ADS)

    Russina, Margarita; Kemner, Ewout; Mezei, Ferenc

    2016-06-01

    In porous materials the molecular confinement is often realized by means of weak Van der Waals interactions between the molecule and the pore surface. The understanding of the mechanism of such interactions is important for a number of applications. In order to establish the role of the confinement size we have studied the microscopic dynamics of molecular hydrogen stored in the nanocages of clathrate hydrates of two different dimensions. We have found that by varying the size of the pore the diffusive mobility of confined hydrogen can be modified in both directions, i.e. reduced or enhanced compared to that in the bulk solid at the same temperatures. In the small cages with a mean crystallographic radius of 3.95 Å the confinement reduces diffusive mobility by orders of magnitude. In contrast, in large cages with a mean radius of 4.75 Å hydrogen molecules displays diffusive jump motion between different equilibrium sites inside the cages, visible at temperatures where bulk H2 is solid. The localization of H2 molecules observed in small cages can promote improved functional properties valuable for hydrogen storage applications.

  19. Peri-aortic Fat, Cardiovascular Disease Risk Factors, and Aortic Calcification: The Framingham Heart Study

    PubMed Central

    Lehman, Sam J.; Massaro, Joseph M.; Schlett, Christopher L.; O’Donnell, Christopher J.; Hoffmann, Udo; Fox, Caroline S.

    2010-01-01

    Objective Perivascular fat through the secretion of paracrine and pro-inflammatory mediators may play a role in obesity-mediated vascular disease. We sought to examine associations between adipose tissue depots immediately surrounding the thoracic aorta, metabolic risk factors, and vascular calcification. Methods In participants free of cardiovascular disease (CVD) from the Framingham Heart Study Offspring cohort who underwent computed tomography (n=1067, mean age 59 years, 56.1% women), thoracic peri-aortic fat depots were quantified. Visceral abdominal tissue (VAT) and calcification of the thoracic and abdominal aorta were also measured. Results Peri-aortic fat depots were correlated with body mass index, waist circumference (WC), VAT (all p<0.0001), hypertension (p<0.007), lower HDL (p<0.0001), serum triglycerides (p<0.0001), impaired fasting glucose (p<0.005), and diabetes (p=0.02). These associations generally remained significant after adjustment for BMI and WC (all p-values<0.05), but not after VAT adjustment. Thoracic aortic fat was associated with thoracic calcification in models containing VAT (OR 1.31, 95% CI 1.01–1.71, p=0.04), but was not significant after adjustment for CVD risk factors (OR 1.16, 95% CI 0.88–1.51, p=0.30). Thoracic aortic fat, however, was associated with abdominal aortic calcification (OR 1.48, 95% CI 1.11–1.98, p=0.008) and coronary artery calcification (OR 1.47, 95% CI 1.09–1.98, p=0.001) even in models including CVD risk factors and VAT. Conclusions Thoracic peri-aortic fat is associated with measures of adiposity, metabolic risk factors, and coronary and abdominal aortic calcification. PMID:20152980

  20. Effects of Cage Density, Sanitation Frequency, and Bedding Type on Animal Wellbeing and Health and Cage Environment in Mice and Rats

    PubMed Central

    Horn, Mandy J; Hudson, Shanice V; Bostrom, Linda A; Cooper, Dale M

    2012-01-01

    The objective of the current study was to evaluate the effects of cage density, sanitation frequency, and bedding type on animal growth and welfare. At weaning, Sprague–Dawley rats and C57BL/6 mice were allocated to treatment groups according to sex, bedding type (shredded aspen, cellulose, or a 50:50 mixture), and cage density and sanitation frequency (inhouse cage density standards and sanitation procedures measured against Guide recommendations) for an 8-wk period. Body weight, feed disappearance, cage ammonia, ATP concentrations, behavior, morbidity, and mortality were assessed weekly; fecal corticosterone, microbiology, and lung histopathology (rats only) were evaluated at the culmination of the trial. In both rats and mice, parameters indicative of animal health and welfare were not significantly affected by cage density and sanitation frequency or bedding type. Occasional effects of feed disappearance and cage ammonia concentrations due to density and sanitation guidelines were noted in rat cages, and bedding type affected cage ammonia and ATP concentrations. Periodic spikes of cage ammonia and ATP concentrations were recorded in mouse cages maintained according to inhouse compared with Guide standards and in cages containing aspen compared with cellulose or aspen–cellulose mixed bedding. Ongoing studies and historical data support the finding that deviations or exceptions from the cage density and sanitation frequency standards set forth in the Guide do not negatively affect animal health, welfare, or production parameters at our institution. These parameters appear to be credible measures of animal health and wellbeing and may be useful for evaluating performance standards for animal husbandry. PMID:23294884

  1. Effects of cage density, sanitation frequency, and bedding type on animal wellbeing and health and cage environment in mice and rats.

    PubMed

    Horn, Mandy J; Hudson, Shanice V; Bostrom, Linda A; Cooper, Dale M

    2012-11-01

    The objective of the current study was to evaluate the effects of cage density, sanitation frequency, and bedding type on animal growth and welfare. At weaning, Sprague-Dawley rats and C57BL/6 mice were allocated to treatment groups according to sex, bedding type (shredded aspen, cellulose, or a 50:50 mixture), and cage density and sanitation frequency (inhouse cage density standards and sanitation procedures measured against Guide recommendations) for an 8-wk period. Body weight, feed disappearance, cage ammonia, ATP concentrations, behavior, morbidity, and mortality were assessed weekly; fecal corticosterone, microbiology, and lung histopathology (rats only) were evaluated at the culmination of the trial. In both rats and mice, parameters indicative of animal health and welfare were not significantly affected by cage density and sanitation frequency or bedding type. Occasional effects of feed disappearance and cage ammonia concentrations due to density and sanitation guidelines were noted in rat cages, and bedding type affected cage ammonia and ATP concentrations. Periodic spikes of cage ammonia and ATP concentrations were recorded in mouse cages maintained according to inhouse compared with Guide standards and in cages containing aspen compared with cellulose or aspen-cellulose mixed bedding. Ongoing studies and historical data support the finding that deviations or exceptions from the cage density and sanitation frequency standards set forth in the Guide do not negatively affect animal health, welfare, or production parameters at our institution. These parameters appear to be credible measures of animal health and wellbeing and may be useful for evaluating performance standards for animal husbandry. PMID:23294884

  2. Aortic Balloon Valvuloplasty Prior to Orthotopic Liver Transplantation: A Novel Approach to Aortic Stenosis and End-Stage Liver Disease

    PubMed Central

    Coverstone, Edward; Korenblat, Kevin; Crippin, Jeffrey S.; Chapman, William C.; Kates, Andrew M.; Zajarias, Alan

    2014-01-01

    The combination of severe aortic stenosis and end-stage liver disease increases the morbidity and mortality of surgical aortic valve replacement or orthotopic liver transplantation resulting in a prohibitive operative risk. We propose a staged approach of balloon aortic valvuloplasty prior to orthotopic liver transplantation as a bridge to definitive aortic valve replacement. Between 2010 and 2012, four patients with severe aortic stenosis and end-stage liver disease underwent staged balloon aortic valvuloplasty followed by orthotopic liver transplantation. All patients had been deemed to be inappropriate candidates for liver transplantation or aortic valve surgery due to their comorbidity. One patient died of complications from a perivalvular abscess. Three patients went on to successful graft implantation and function and surgical recovery. Two of the three patients proceeded to definitive surgical aortic valve replacement with the remainder currently undergoing evaluation. In this case series, we present a novel approach of balloon aortic valvuloplasty prior to liver transplantation as a potential bridge to definitive treatment of severe aortic stenosis in the end-stage liver patient. PMID:25431682

  3. Valve Replacement with a Sutureless Aortic Prosthesis in a Patient with Concomitant Mitral Valve Disease and Severe Aortic Root Calcification

    PubMed Central

    Scafuri, Antonio; Nicolò, Francesca; Chiariello, Luigi

    2016-01-01

    Aortic valve replacement with concomitant mitral valve surgery in the presence of severe aortic root calcification is technically difficult, with long cardiopulmonary bypass and aortic cross-clamp times. We performed sutureless aortic valve replacement and mitral valve annuloplasty in a 68-year-old man who had severe aortic stenosis and moderate-to-severe mitral regurgitation. Intraoperatively, we found severe calcification of the aortic root. We approached the aortic valve through a transverse aortotomy, performed in a higher position than usual, and we replaced the valve with a Sorin Perceval S sutureless prosthesis. In addition, we performed mitral annuloplasty with use of an open rigid ring. The aortic cross-clamp time was 63 minutes, and the cardiopulmonary bypass time was 83 minutes. No paravalvular leakage of the aortic prosthesis was detected 30 days postoperatively. Our case shows that the Perceval S sutureless bioprosthesis can be safely implanted in patients with aortic root calcification, even when mitral valve disease needs surgical correction. PMID:27127442

  4. Effects of single caging and cage size on behavior and stress level of domestic neutered cats housed in an animal shelter.

    PubMed

    Uetake, Katsuji; Goto, Akihiro; Koyama, Rumi; Kikuchi, Rieko; Tanaka, Toshio

    2013-03-01

    Cats need a minimum amount of space even in animal shelters. In this study the effects of single caging and cage size on the behavior and stress level of domestic cats were investigated. Six neutered cats (2-15 years old) that had been housed in a group for at least 7 months were moved to three kinds of single cages (small, medium and large) by rotation on a Latin square design. They experienced each cage size for 6 days. Cats could use vertical dimensions when housed in a group room and the large cage. Behavioral observation was conducted for 3 h in the evening, and stress levels were assessed by urine cortisol-to-creatinine ratios. The amounts (estimated proportions) of time spent in locomotion and social/solitary play were lower even in large cages than in group housing (both P < 0.05). Conversely, the amount of time spent resting tended to increase when housed singly (P = 0.104). The urine cortisol-to-creatinine ratios of singly housed cats tended to be higher than that of group-housed cats (P = 0.086). The results indicate that cats become less active when they are housed singly in cages regardless of the cage size. Cats seem to feel no undue stress even in small cages if the stay is short. PMID:23480709

  5. Aortic Blood Flow Reversal Determines Renal Function: Potential Explanation for Renal Dysfunction Caused by Aortic Stiffening in Hypertension.

    PubMed

    Hashimoto, Junichiro; Ito, Sadayoshi

    2015-07-01

    Aortic stiffness determines the glomerular filtration rate (GFR) and predicts the progressive decline of the GFR. However, the underlying pathophysiological mechanism remains obscure. Recent evidence has shown a close link between aortic stiffness and the bidirectional (systolic forward and early diastolic reverse) flow characteristics. We hypothesized that the aortic stiffening-induced renal dysfunction is attributable to altered central flow dynamics. In 222 patients with hypertension, Doppler velocity waveforms were recorded at the proximal descending aorta to calculate the reverse/forward flow ratio. Tonometric waveforms were recorded to measure the carotid-femoral (aortic) and carotid-radial (peripheral) pulse wave velocities, to estimate the aortic pressure from the radial waveforms, and to compute the aortic characteristic impedance. In addition, renal hemodynamics was evaluated by duplex ultrasound. The estimated GFR was inversely correlated with the aortic pulse wave velocity, reverse/forward flow ratio, pulse pressure, and characteristic impedance, whereas it was not correlated with the peripheral pulse wave velocity or mean arterial pressure. The association between aortic pulse wave velocity and estimated GFR was independent of age, diabetes mellitus, hypercholesterolemia, and antihypertensive medication. However, further adjustment for the aortic reverse/forward flow ratio and pulse pressure substantially weakened this association, and instead, the reverse/forward flow ratio emerged as the strongest determinant of estimated GFR (P=0.001). A higher aortic reverse/forward flow ratio was also associated with lower intrarenal forward flow velocities. These results suggest that an increase in aortic flow reversal (ie, retrograde flow from the descending thoracic aorta toward the aortic arch), caused by aortic stiffening and impedance mismatch, reduces antegrade flow into the kidney and thereby deteriorates renal function. PMID:25916721

  6. Environmental enrichment for rhesus macaques: a cost-effective exercise cage.

    PubMed

    Storey, P L; Turner, P V; Tremblay, J L

    2000-01-01

    Providing suitable and varied environmental enrichment opportunities for nonhuman primates is both challenging and expensive, requiring institutions to be innovative when planning an enrichment program. Equipment must be durable, nontoxic, easily sanitized and disinfected, and readily assembled or prepared by animal care personnel. We developed a portable exercise cage for singly housed macaques from pre-existing but outdated caging; our cage met the described requirements and was used in animal-holding rooms. Modifying existing caging for this purpose led to substantial cost savings. These cages have proved to be popular with animals and their affiliated research teams. PMID:11178309

  7. The many faces of aortic dissections: Beware of unusual presentations.

    PubMed

    Scaglione, Mariano; Salvolini, Luca; Casciani, Emanuele; Giovagnoni, Andrea; Mazzei, Maria Antonietta; Volterrani, Luca

    2008-03-01

    Aortic dissection is gaining recognition in Western societies, and it is being diagnosed with increasing frequency. New diagnostic imaging modalities, longer life expectancy, as well as the increase in the number patients suffering from hypertension have all contributed to the growing awareness of aortic dissection. Nevertheless, as many as 30% of patients ultimately diagnosed with acute dissection are first thought to be suffering from something else. The increased availability and use of multidetector computed tomography has led to the incidental discovery of aortic dissection in very different settings. This article focuses on unusual presentations of painless aortic dissection. It is important for radiologists to remember that aortic dissections may present in different ways, not only as an acute, critical fatality but also with subtle, unusual signs and symptoms, which apparently do not seem to be strictly related to aortic diseases. PMID:17950552

  8. Chest radiography in acute aortic syndrome: pearls and pitfalls.

    PubMed

    Chawla, Ashish; Rajendran, Surendran; Yung, Wai Heng; Babu, Suresh Balasubramanian; Peh, Wilfred C

    2016-08-01

    Acute aortic syndrome is a group of life-threatening diseases of the thoracic aorta that usually present to the emergency department. It includes aortic dissection, aortic intramural hematoma, and penetrating aortic ulcer. Rare aortic pathologies of aorto-esophageal fistula and mycotic aneurysm may also be included in this list. All these conditions require urgent treatment with complex clinical care and management. Most patients who present with chest pain are evaluated with a chest radiograph in the emergency department. It is important that maximum diagnostic information is extracted from the chest radiograph as certain signs on the chest radiograph are extremely useful in pointing towards the diagnosis of acute aortic syndrome. PMID:27282377

  9. [Use of sutureless prosthetic aortic valves in cardiac surgery].

    PubMed

    Santarpino, Giuseppe; Fischlein, Theodor

    2014-03-01

    In the last years, an increasing proportion of high-risk patients undergo surgical aortic valve replacement. In order to reduce the risk associated with cross-clamp time or cardioplegic ischemic time, sutureless aortic prostheses have been developed. These bioprosthetic valves are not hand sewn, and this technological advance translates into reduced implantation times, thus improving outcome of patients referred for aortic valve replacement. At present, three sutureless bioprostheses are available on the market: 3f Enable (Medtronic Inc., Minneapolis, Minnesota, USA), Perceval (Sorin Group, Saluggia, Italy) and Intuity (Edwards Lifesciences, Irvine, California, USA). This article provides an overview of the available literature on sutureless aortic valves with the aim to better define current role and future perspectives of sutureless aortic bioprostheses for the treatment of aortic valve stenosis. PMID:24770430

  10. Effects of intra-aortic counterpulsation on aortic wall energetics and damping: in vivo experiments.

    PubMed

    Fischer, Edmundo I Cabrera; Bia, Daniel; Camus, Juan M; Zócalo, Yanina; de Forteza, Eduardo; Armentano, Ricardo L

    2008-01-01

    Intra-aortic balloon pumping (IABP) could modify the arterial biomechanics; however, its effects on arterial wall properties have not been fully explored. This dynamical study was designed to characterize the pressure-dependent and smooth muscle-dependent effects of IABP on aortic wall energetics in an in vivo animal model. Intra-aortic balloon pumping (1:2) was performed in six anesthetized sheep in which aortic pressure and diameter signals were measured in basal, augmented (during balloon inflation), and assisted (postaugmented) beats. Energy dissipation values in augmented and assisted beats were significantly higher than those observed in basal state (p < 0.05). Assisted beats showed a significant increase of wall damping with respect to basal and augmented beats (p < 0.05). Intra-aortic balloon pumping resulted in a significant increase of pulse wave velocity (p < 0.05) in augmented beats with respect to basal state (6.3 +/- 0.8 vs. 5.2 +/- 0.5 m x s(-1)); whereas values observed in assisted beats were significantly (p < 0.05) lower than those observed in augmented beats (4.9 +/- 0.5 vs. 6.3 +/- 0.8 m x s(-1)). Our findings show that IABP determined the pressure and smooth muscle-dependent changes in arterial wall energetics and damping properties in this animal model. PMID:18204315

  11. Haemodynamics in the mouse aortic arch computed from MRI-derived velocities at the aortic root.

    PubMed

    Van Doormaal, Mark A; Kazakidi, Asimina; Wylezinska, Marzena; Hunt, Anthony; Tremoleda, Jordi L; Protti, Andrea; Bohraus, Yvette; Gsell, Willy; Weinberg, Peter D; Ethier, C Ross

    2012-11-01

    Mice are widely used to investigate atherogenesis, which is known to be influenced by stresses related to blood flow. However, numerical characterization of the haemodynamic environment in the commonly studied aortic arch has hitherto been based on idealizations of inflow into the aorta. Our purpose in this work was to numerically characterize the haemodynamic environment in the mouse aortic arch using measured inflow velocities, and to relate the resulting shear stress patterns to known locations of high- and low-lesion prevalence. Blood flow velocities were measured in the aortic root of C57/BL6 mice using phase-contrast MRI. Arterial geometries were obtained by micro-CT of corrosion casts. These data were used to compute blood flow and wall shear stress (WSS) patterns in the arch. WSS profiles computed using realistic and idealized aortic root velocities differed significantly. An unexpected finding was that average WSS in the high-lesion-probability region on the inner wall was actually higher than the WSS in the low-probability region on the outer wall. Future studies of mouse aortic arch haemodynamics should avoid the use of idealized inflow velocity profiles. Lesion formation does not seem to uniquely associate with low or oscillating WSS in this segment, suggesting that other factors may also play a role in lesion localization. PMID:22764131

  12. Enlargement of the aortic annulus during aortic valve replacement: a review.

    PubMed

    Bortolotti, Uberto; Celiento, Michele; Milano, Aldo D

    2014-01-01

    The main goal of aortic valve replacement (AVR) is to obtain relief from the fixed left ventricular (LV) obstruction by replacing the aortic valve with a prosthesis, either mechanical or biological, of adequate size. Most currently available prostheses provide satisfactory hemodynamic performance, but small-sized prostheses may be associated with high transvalvular gradients and suboptimal effective orifice area that result in prosthesis-patient mismatch (PPM), and thus are far from ideal for use in young, active patients. The avoidance of PPM is advisable as it has been repeatedly associated with increased mortality, decreased exercise tolerance and an impaired regression of LV hypertrophy after AVR for severe aortic stenosis. Enlargement of the aortic annulus (EAA) has proved to be a valuable method to prevent PPM in the presence of a diminutive aortic root. This review outlines the various techniques described for EAA, presenting technical details, long-term results and major procedure-related complications, and discussing the current role of EAA in patients requiring AVR. PMID:24779326

  13. Aneurysm of an Aberrant Right Subclavian Artery Successfully Excluded by a Thoracic Aortic Stent Graft with Supra-aortic Bypass of Three Arch Vessels

    SciTech Connect

    Munneke, Graham J. Loosemore, Thomas M.; Belli, Anna-Maria; Thompson, Matt M.; Morgan, Robert A.

    2005-06-15

    An aberrant right subclavian artery (ARSA) arising from a left-sided aortic arch is the fourth most common aortic arch anomaly. Aneurysmal dilatation of the ARSA requires treatment because of the associated risk of rupture. We present a case where supra-aortic bypass of the arch vessels was performed to facilitate exclusion of the aneurysm by a thoracic aortic stent graft.

  14. Environmental impacts of cage culture in Lake Victoria: the case of Shirati Bay-Sota, Tanzania.

    PubMed

    Kashindye, Benedicto Boniphace; Nsinda, P; Kayanda, R; Ngupula, G W; Mashafi, C A; Ezekiel, C N

    2015-01-01

    The experimental cage culture was conducted at Shirati bay, Lake Victoria from February to August 2013, to investigate the impacts of the small scale cage culture on the environment. Three locations along the cages, at the intermediate and one in the offshore (control) were sampled for water quality parameters, phytoplankton and macro invertebrates. A notable increase in nutrient concentration was observed after the set of cages among the stations. However DO, pH, and water transparency showed no major changes and was within the recommended ranges. Cyanophytes an indicator of inorganic pollution dominated before and after the set of cages, an increase in phytoplankton numerical abundance was observed after stocking of fish in cages. In addition there was an increase in the invertebrate community especially bivalves and gastropods. In conclusion we found no consistent environmental change caused by cage culture, and therefore it can be allowed in Lake Victoria, Tanzania part, with close monitoring of its impacts. PMID:26361576

  15. Housing of pregnant rats in metabolism cages: maternal and developmental effects.

    PubMed

    Bosque, M A; Domingo, J L; Corbella, J

    1994-10-01

    The influence of the caging conditions on maternal and gestational variables was assessed for pregnant rats housed individually in two cage types. Plug-positive Sprague-Dawley females were caged either in Makrolon or in metabolism (Tecniplast) cages, and were not disturbed throughout all the gestational period. Cesarean sections were performed on gestation day 20. All live fetuses were examined for external, internal, and skeletal malformations and variations. Pregnant rats were affected by the housing system, as evidenced by a significant weight loss and reduced food consumption in the animals housed in metabolism cages. A moderate increase in the number of total skeletal defects was also observed in the fetuses of dams housed in metabolism cages. An important implication of these results would be that in maternal and developmental toxicity studies of xenobiotics, pregnant animals should not be housed in metabolism cages. PMID:7894240

  16. Left main compression by an aortic root abscess.

    PubMed

    Misuraca, Leonardo; De Caro, Francesco; De Carlo, Marco; Barzaghi, Carlo; Scioti, Gianni; Minzioni, Gaetano; Petronio, Anna S

    2012-03-01

    A 79-year-old man with severe aortic stenosis, history of coronary artery disease and a recent hospitalization for sepsis presented at our institution following a syncope and angina at rest. Coronary angiography and aortography showed an aortic root abscess, causing left main coronary artery compression. This life-threatening complication of aortic valve endocarditis is rare and requires immediate surgical correction. PMID:22306781

  17. Operative Treatment of Combined Aortic Stenosis and Coronary Artery Disease

    PubMed Central

    Kadric, Nedzad; Kabil, Emir; Mujanovic, Emir; Hadziselimovic, Mehdin; Jahic, Mirza; Rajkovic, Stojan; Osmanovic, Enes; Avdic, Sevleta; Keranovic, Suad; Behrem, Adnan

    2015-01-01

    Introduction: The aortic valve replacement is a standard operating procedure in patients with severe aortic stenosis. Structure of patients undergoing surgery ranges from young population with isolated mitral valvular disease to the elderly population, which is in addition to the underlying disease additionally burdened with comorbidity. One of the most commonly present factors that further complicate the surgery is coronary heart disease that occurs in, almost, one third of patients with aortic stenosis. The aim is to compare the results of surgery for aortic valve replacement with or without coronary artery bypass graft (CABG). Patients and Methods: From August 2008 to January 2013 in our center operated on 120 patients for aortic stenosis. Of this number, 75 were men and 45 women. The average age was 63.37 years (16-78). Isolated aortic valve replacement was performed in 89 patients and in 31 patients underwent aortic valve replacement and coronary bypass surgery. Implanted 89 biological and 31 mechanical valves. Results: Patients with associated aortic stenosis and coronary artery disease were more expressed symptomatic symptoms preoperatively to patients with isolated aortic stenosis who were on average younger age. Intra-hospital morbidity and mortality was more pronounced in the group of patients with concomitant aortic valve replacement and coronary bypass surgery. Morbidity was recorded in 17 patients (14.3%) in both groups, while the mortality rate in both groups was 12 patients (10.1%). Conclusion: Evaluation of preoperative risk factors and comorbidity in patients with aortic stenosis and coronary artery disease contributes to a significant reduction in intraoperative and postoperative complications. Also, early diagnosis of associated coronary artery disease and aortic stenosis contributes to timely decision for surgery thus avoiding subsequent ischaemic changes and myocardial damage. PMID:25870480

  18. Immunoglobulin G4-related large thoraco-abdominal aortic aneurysm.

    PubMed

    Sekine, Yuji; Yamamoto, Shin; Fujikawa, Takuya; Sasaguri, Shiro

    2016-07-01

    We report a case of immunoglobulin G4-related large thoraco-abdominal aortic aneurysm in a 38-year old man. Preoperative contrast-enhanced computed tomography revealed that the mid-descending thoracic aorta was extremely enlarged and the maximum diameter of the aneurysm was 92 mm. The patient underwent thoraco-abdominal aortic replacement through a thoraco-abdominal incision under left heart bypass. The postoperative pathological examination diagnosed immunoglobulin G4-related aortic aneurysm. PMID:27059069

  19. CT and MRI in the Evaluation of Thoracic Aortic Diseases

    PubMed Central

    2013-01-01

    Computed tomography (CT) and magnetic resonance imaging (MRI) are the most commonly used imaging examinations to evaluate thoracic aortic diseases because of their high spatial and temporal resolutions, large fields of view, and multiplanar imaging reconstruction capabilities. CT and MRI play an important role not only in the diagnosis of thoracic aortic disease but also in the preoperative assessment and followup after treatment. In this review, the CT and MRI appearances of various acquired thoracic aortic conditions are described and illustrated. PMID:24396601

  20. Absent Aortic Valve in DiGeorge Syndrome.

    PubMed

    Bertsch, Elizabeth C; Minturn, Lucy; Gotteiner, Nina L; Ernst, Linda M

    2016-01-01

    A 20-week-old fetus with the 22q11.2 deletion characteristic of DiGeorge syndrome is described with vertebral segmentation abnormalities and complex cardiovascular anomalies including an absent aortic valve. This is only the second known case of absent aortic valve in association with DiGeorge syndrome. We discuss the association of absent aortic valve with other conotruncal defects and the utility of fetal echocardiography in the diagnosis of DiGeorge syndrome. PMID:26230226

  1. Reconstructing the infected aortic root with antibiotic impregnated biological glue.

    PubMed

    McGiffin, David C; Davies, James E; Kirklin, James K

    2014-05-01

    Prosthetic valve dehiscence and persistent infection are two complications following reconstruction of the aortic root in destructive endocarditis. A technique is described involving the principles of aggressive debridement, closure of large abscess cavities with biological material incorporating a slurry of antibiotic-impregnated biological sealant, and replacement of the aortic valve with an aortic allograft valve. This strategy appears to have been successful in preventing persistent endocarditis and valve dehiscence in a limited number of patients. PMID:24433228

  2. Spontaneous aortic dissecting hematoma in two dogs.

    PubMed

    Boulineau, Theresa Marie; Andrews-Jones, Lydia; Van Alstine, William

    2005-09-01

    This report describes 2 cases of spontaneous aortic dissecting hematoma in young Border Collie and Border Collie crossbred dogs. Histology was performed in one of the cases involving an unusual splitting of the elastin present within the wall of the aorta, consistent with elastin dysplasia as described in Marfan syndrome in humans. The first case involved a young purebred Border Collie that died suddenly and the second case involved a Border Collie crossbred dog that died after a 1-month history of seizures. Gross lesions included pericardial tamponade with dissection of the ascending aorta in the former case and thoracic cavity hemorrhage, mediastinal hematoma, and aortic dissection in the latter. Histologic lesions in the case of the Border Collie crossbred dog included a dissecting hematoma of the ascending aorta with elastin dysplasia and right axillary arterial intimal proliferation. PMID:16312247

  3. Tubercular mycotic aortic aneurysm: A case report

    PubMed Central

    Kumar, Satish; Babu, NM Sharath; Jaret, Pramod; Sharma, Ashok

    2016-01-01

    Tubercular aneurysms of larger vessels, particularly the aorta is very rare. The first case of tubercular involvement of the aorta in the form of aortitis was reported in 1882 by Weigert and the first case of tubercular mycotic aneurysm of the aorta was reported in 1895. The preoperative diagnosis of tubercular aortic aneurysm is difficult. Even at surgery, determining the tubercular nature of the lesion is problematic. The gross appearance may not be distinctive, and acid-fast stains are unlikely to be performed. We report the case of a young female patient who was started on antitubercular treatment for pleural effusion and was found to have aortic aneurysm, which later on proved to be tubercular in origin. PMID:27051108

  4. Cardiovocal Syndrome Secondary to an Aortic Aneurysm

    PubMed Central

    Wang, Hsing-Won; Chen, Mei-Chien; Chao, Pin-Zhir; Lee, Fei-Peng

    2016-01-01

    We reported that a 68-year-old man presented to the ENT outpatient department complaining of hoarseness for more than 10 months. Clinical exam identified left vocal palsy in the paramedian position and atrophic vocal folds were noted. Chest radiography revealed a large bulging contour overlying aorta and left hilar shadow. Aortic aneurysm was proved by CT scanning. Contrast-enhanced chest computed tomography for further evaluation showed a broad-based aortic aneurysm at proximal descending aorta, projecting anterolaterally. Cardiovocal syndrome was proved. The syndrome is a rare clinical presentation. While a patient with unilateral vocal palsy is encountered, one might keep in mind the possibility of cardiovocal syndrome especially in an adult who had a cardiovascular disease. PMID:27088024

  5. Cardiovocal Syndrome Secondary to an Aortic Aneurysm.

    PubMed

    Wang, Hsing-Won; Chen, Mei-Chien; Chao, Pin-Zhir; Lee, Fei-Peng

    2016-01-01

    We reported that a 68-year-old man presented to the ENT outpatient department complaining of hoarseness for more than 10 months. Clinical exam identified left vocal palsy in the paramedian position and atrophic vocal folds were noted. Chest radiography revealed a large bulging contour overlying aorta and left hilar shadow. Aortic aneurysm was proved by CT scanning. Contrast-enhanced chest computed tomography for further evaluation showed a broad-based aortic aneurysm at proximal descending aorta, projecting anterolaterally. Cardiovocal syndrome was proved. The syndrome is a rare clinical presentation. While a patient with unilateral vocal palsy is encountered, one might keep in mind the possibility of cardiovocal syndrome especially in an adult who had a cardiovascular disease. PMID:27088024

  6. Optimal Design of Aortic Leaflet Prosthesis

    NASA Technical Reports Server (NTRS)

    Ghista, Dhanjoo N.; Reul, Helmut; Ray, Gautam; Chandran, K. B.

    1978-01-01

    The design criteria for an optimum prosthetic-aortic leaflet valve are a smooth washout in the valve cusps, minimal leaflet stress, minimal transmembrane pressure for the valve to open, an adequate lifetime (for a given blood-compatible leaflet material's fatigue data). A rigorous design analysis is presented to obtain the prosthetic tri-leaflet aortic valve leaflet's optimum design parameters. Four alternative optimum leaflet geometries are obtained to satisfy the criteria of a smooth washout and minimal leaflet stress. The leaflet thicknesses of these four optimum designs are determined by satisfying the two remaining design criteria for minimal transmembrane opening pressure and adequate fatigue lifetime, which are formulated in terms of the elastic and fatigue properties of the selected leaflet material - Avcothane-51 (of the Avco-Everett Co. of Massachusetts). Prosthetic valves are fabricated on the basis of the optimum analysis and the resulting detailed engineering drawings of the designs are also presented in the paper.

  7. Geometry of aortic heart valves. [prosthetic design

    NASA Technical Reports Server (NTRS)

    Karara, H. M.

    1975-01-01

    Photogrammetric measurements of the surface topography of the aortic valves obtained from silicon rubber molds of freshly excised human aortic valves are presented. The data are part of an investigation into the design of a new prosthetic valve which will be a central-flow device, like the real valve and unlike previous central-occluding prostheses. Since the maximum stress on the heart valve is induced when the valve is closed and subject to diastolic back-pressure, it was decided to determine the valve geometry during diastole. That is, the molds were formed by pouring the rubber down the excised aortas, causing the valves to close. The molds were made under different pressures (20-120 torr); photogrammetry served as a vehicle for the assessment of the mold topography through the following outputs: digital models, surface profiles, and contour maps.

  8. Single Coronary Artery with Aortic Regurgitation

    SciTech Connect

    Katsetos, Manny C. Toce, Dale T.

    2003-11-15

    An isolated single coronary artery can be associated with normal life expectancy; however, patients are at an increased risk of sudden death. A case is reported of a 54-year-old man with several months of chest pressure with activity. On exercise Sestamibi stress testing, the patient developed a hypotensive response with no symptoms and minimal electrocardiographic changes. Nuclear scanning demonstrated reversible septal and lateral perfusion defects consistent with severe ischemia. Coronary angiography revealed a single coronary artery with the right coronary artery arising from the left main. There were high-grade stenotic lesions in the left anterior descending and circumflex arteries with only moderate atherosclerotic disease in the right coronary artery. An aortogram showed 2-3+ aortic regurgitation, with an ejection fraction of 45% on ventriculography. The patient underwent four-vessel revascularization and aortic valve replacement and did well postoperatively.

  9. Spinal cord protection in aortic endovascular surgery.

    PubMed

    Scott, D A; Denton, M J

    2016-09-01

    A persistent neurological deficit, such as paraplegia or paraparesis, secondary to spinal cord injury remains one of the most feared complications of surgery on the descending thoracic or abdominal aorta. This is despite sophisticated advances in imaging and the use of less invasive endovascular procedures. Extensive fenestrated endovascular aortic graft prostheses still carry a risk of spinal cord injury of up to 10%; thus, this risk should be identified and strategies implemented to protect the spinal cord and maintain perfusion. The patients at highest risk are those undergoing extensive thoracic aortic stenting including thoracic, abdominal, and pelvic vessels. Although many techniques are available, lumbar cerebrospinal fluid drainage remains the most frequent intervention, along with maintenance of perfusion pressure and possibly staged procedures to allow collateral vessel stabilization. Many questions remain regarding other technical aspects, spinal cord monitoring and cooling, pharmacological protection, and the optimal duration of interventions into the postoperative period. PMID:27566805

  10. Animal Welfare and Food Safety Aspects of Confining Broiler Chickens to Cages

    PubMed Central

    Shields, Sara; Greger, Michael

    2013-01-01

    Simple Summary In commercial chicken meat production, broiler chickens are usually kept on the floor in ware-house like buildings, but the use of cages is becoming more common. Confining chickens to cages is a welfare problem, as has been thoroughly demonstrated for laying hens used for egg production. Caged broiler chickens may suffer from poor bone strength due to lack of exercise, feather loss, and restriction of natural behavior. There are also potential food safety concerns associated with the use of cages. While cages may provide an economic advantage in some geographical regions of the world, the severe, inherent disadvantages should also be considered before cages are more widely adopted in the global broiler chicken industry. Abstract In most areas of the world, broiler chickens are raised in floor systems, but cage confinement is becoming more common. The welfare of broiler chickens in cages is affected by movement restriction, poor bone strength due to lack of exercise, and prevention of key behavioral patterns such as dustbathing and ground scratching. Cages for broiler chickens also have a long history of causing skin and leg conditions that could further compromise welfare, but a lack of controlled studies makes it difficult to draw conclusions about newer cage designs. Cage environments are usually stocked at a higher density than open floor systems, and the limited studies available suggest that caging may lead to increased levels of fear and stress in the birds. Further, birds reared on the floor appear less likely to harbor and shed Salmonella, as litter may serve as a seeding agent for competitive exclusion by other microorganisms. Cages for laying hens used in egg production have met with substantial opposition due to welfare concerns and caging broiler chickens will likely be subject to the same kinds of social disapproval. PMID:26487409

  11. Initial hydrodynamic study on a new intraaortic axial flow pump: Dynamic aortic valve.

    PubMed

    Li, G; Zhao, H; Hu, S; Zhu, X; Wu, Q; Ren, B; Ma, W

    2001-04-01

    Rotary blood pumps have been researched as implantable ventricular assist devices for years. To further reduce the complex of implanted axial pumps, the authors proposed a new concept of intraaortic axial pump, termed previously as "dynamic aortic valve (DAV)". Instead of being driven by an intraaortic micro-electric motor, it was powered by a magnetic field from outside of body. To ensure the perfusion of coronary artery, the axial flow pump is to be implanted in the position of aortic valve. It could serve as either a blood pump or a mechanical valve depending on the power input. This research tested the feasibility of the new concept in model study. A column, made from permanent magnet, is jointed to an impeller in a concentric way to form a "rotor-impeller". Supported by a hanging shaft cantilevered in the center of a rigid cage, the rotor-impeller can be turned by the magnetic field in the surrounding space. In the present prototype, the rotor is 8 mm in diameter and 15 mm in length, the impeller has 3 vanes with an outer diameter of 18 mm. The supporting cage is 22 mm in outer diameter and 20 mm in length. When tested, the DAV prototype is inserted into the tube of a mock circuit. The alternative magnetic field is produced by a rotating magnet placed side by side with the rotor-impeller at a distance of 30 mm. Once the alternative magnetic field is presented in the surrounding space, the DAV starts to turn, leading to a pressure difference and liquid flow in the tube. The flow rate or pressure difference is proportioned to rotary speed. At the maximal output of hydraulic power, the flow rate reached 5 L/min against an afterload of 100 mmHg. The maximal pressure difference generated by DAV at a rotation rate of 12600 r/min was 147 mmHg. The preliminary results demonstrated the feasibility of "DAV", further research on this concept is justifiable. PMID:18726438

  12. FOXE3 mutations predispose to thoracic aortic aneurysms and dissections

    PubMed Central

    Kuang, Shao-Qing; Medina-Martinez, Olga; Guo, Dong-chuan; Gong, Limin; Regalado, Ellen S.; Reynolds, Corey L.; Boileau, Catherine; Jondeau, Guillaume; Prakash, Siddharth K.; Kwartler, Callie S.; Zhu, Lawrence Yang; Peters, Andrew M.; Duan, Xue-Yan; Bamshad, Michael J.; Shendure, Jay; Nickerson, Debbie A.; Santos-Cortez, Regie L.; Dong, Xiurong; Leal, Suzanne M.; Majesky, Mark W.; Swindell, Eric C.; Jamrich, Milan; Milewicz, Dianna M.

    2016-01-01

    The ascending thoracic aorta is designed to withstand biomechanical forces from pulsatile blood. Thoracic aortic aneurysms and acute aortic dissections (TAADs) occur as a result of genetically triggered defects in aortic structure and a dysfunctional response to these forces. Here, we describe mutations in the forkhead transcription factor FOXE3 that predispose mutation-bearing individuals to TAAD. We performed exome sequencing of a large family with multiple members with TAADs and identified a rare variant in FOXE3 with an altered amino acid in the DNA-binding domain (p.Asp153His) that segregated with disease in this family. Additional pathogenic FOXE3 variants were identified in unrelated TAAD families. In mice, Foxe3 deficiency reduced smooth muscle cell (SMC) density and impaired SMC differentiation in the ascending aorta. Foxe3 expression was induced in aortic SMCs after transverse aortic constriction, and Foxe3 deficiency increased SMC apoptosis and ascending aortic rupture with increased aortic pressure. These phenotypes were rescued by inhibiting p53 activity, either by administration of a p53 inhibitor (pifithrin-α), or by crossing Foxe3–/– mice with p53–/– mice. Our data demonstrate that FOXE3 mutations lead to a reduced number of aortic SMCs during development and increased SMC apoptosis in the ascending aorta in response to increased biomechanical forces, thus defining an additional molecular pathway that leads to familial thoracic aortic disease. PMID:26854927

  13. Acute aortic dissection caused by Clostridium septicum aortitis.

    PubMed

    Eplinius, Franziska; Hädrich, Carsten

    2014-11-01

    Clostridium septicum aortitis is a rare cause of aortic dissection. So far, only 28 cases have been described in literature before. Most of these cases occurred in elderly patients and an association to colonic neoplasms and/or atherosclerosis has been witnessed frequently. Here we report the case of a 32-year-old man with fatal aortic dissection due to aortic infection with C. septicum. Beside a case of a 22-year-old man who died of aortic dissection due to C. septicum aortitis this is the second case of C. septicum aortitis in a young individual with no signs of colonic neoplasms or atherosclerosis. PMID:25242573

  14. Aortic root abscess resulting from endocarditis: spectrum of angiographic findings

    SciTech Connect

    Miller, S.W.; Dinsmore, R.E.

    1984-11-01

    Abscesses in the aortic root are a serious complication of infective endocarditis and require accurate diagnosis for antibiotic and surgical management. Nineteen cases of endocarditis of a native valve or prosthetic valve and adjacent abscess cavities were identified with angiography. Of 6 patients with endocarditis of a native valve, 5 had bicuspid aortic valves and all had severe aortic regurgitation. Of 13 patients with endocarditis of a prosthetic aortic valve, all had paravalvular regurgitation. Fistulas were detected into the mitral anulus in 8 patients, and into the right ventricle in 3 patients. No complications from the catheterization were recorded during the 48-hour follow-up.

  15. Chronic Thoracic Aortic Aneurysm Presenting 29 Years following Trauma

    PubMed Central

    Miller, Sarah; Kumar, Prashant; Van den Bosch, Rene; Khanafer, Adib

    2015-01-01

    Blunt, nonpenetrating injuries of the thoracic aorta are uncommon and associated with a high mortality rate within the first hour. Aortic injury is missed in 1-2% of patients that survive to hospital, and a chronic thoracic aortic aneurysm may subsequently form. We present a case in which a chronic thoracic aortic aneurysm was diagnosed 29 years following a significant motor vehicle accident. We discuss the epidemiology, presentation, and management of this uncommon consequence of blunt, nonpenetrating aortic injury. Our case illustrates an important clinical lesson; a past medical history of trauma should not be overlooked at any patient assessment. PMID:26351610

  16. [Single coronary artery and right aortic arch].

    PubMed

    Martínez-Quintana, Efrén; Rodríguez-González, Fayna

    2015-01-01

    Coronary anomalies are mostly asymptomatic and diagnosed incidentally during coronary angiography or echocardiography. However, they must be taken into account in the differential diagnosis of angina, dyspnea, syncope, acute myocardial infarction or sudden death in young patients. The case is presented of two rare anomalies, single coronary artery originating from right sinus of Valsalva and right aortic arch, in a 65 year-old patient with atherosclerotic coronary artery disease treated percutaneously. PMID:25304052

  17. Total Percutaneous Aortic Repair: Midterm Outcomes

    SciTech Connect

    Bent, Clare L. Fotiadis, Nikolas; Renfrew, Ian; Walsh, Michael; Brohi, Karim; Kyriakides, Constantinos; Matson, Matthew

    2009-05-15

    The purpose of this study was to examine the immediate and midterm outcomes of percutaneous endovascular repair of thoracic and abdominal aortic pathology. Between December 2003 and June 2005, 21 patients (mean age: 60.4 {+-} 17.1 years; 15 males, 6 females) underwent endovascular stent-graft insertion for thoracic (n = 13) or abdominal aortic (n = 8) pathology. Preprocedural computed tomographic angiography (CTA) was performed to assess the suitability of aorto-iliac and common femoral artery (CFA) anatomy, including the degree of CFA calcification, for total percutaneous aortic stent-graft repair. Percutaneous access was used for the introduction of 18- to 26-Fr delivery devices. A 'preclose' closure technique using two Perclose suture devices (Perclose A-T; Abbott Vascular) was used in all cases. Data were prospectively collected. Each CFA puncture site was assessed via clinical examination and CTA at 1, 6, and 12 months, followed by annual review thereafter. Minimum follow-up was 36 months. Outcome measures evaluated were rates of technical success, conversion to open surgical repair, complications, and late incidence of arterial stenosis at the site of Perclose suture deployment. A total of 58 Perclose devices were used to close 29 femoral arteriotomies. Outer diameters of stent-graft delivery devices used were 18 Fr (n = 5), 20 Fr (n = 3), 22 Fr (n = 4), 24 Fr (n = 15), and 26 Fr (n = 2). Percutaneous closure was successful in 96.6% (28/29) of arteriotomies. Conversion to surgical repair was required at one access site (3.4%). Mean follow-up was 50 {+-} 8 months. No late complications were observed. By CT criteria, no patient developed a >50% reduction in CFA caliber at the site of Perclose deployment during the study period. In conclusion, percutaneous aortic stent-graft insertion can be safely performed, with a low risk of both immediate and midterm access-related complications.

  18. Crater-Like Ulceration of Aortic Arch.

    PubMed

    Simon, Caterina; Calabrese, Alice; Canu, Gianluca; Merlo, Maurizio; Galletti, Lorenzo

    2014-12-01

    We report the case of a 78-year-old female who presented to our hospital with signs of hemorrhagic shock and breathlessness. A transthoracic echocardiography demonstrated pericardial effusion. Computed tomography of the chest showed a penetrating atherosclerotic ulcer of the aortic arch with an intramural hematoma of the ascending and descending aorta. Endovascular repair with stent-grafting was urgently performed and a pericardial window placement was done to reduce mediastinal bleeding. PMID:26798748

  19. The vanishing giant abdominal aortic aneurysm.

    PubMed

    Krivoshei, Lian; Halak, Moshe; Schneiderman, Jacob; Silverberg, Daniel

    2011-05-01

    Spontaneous sac size regression of a giant abdominal aortic aneurysm (AAA) is a rare event that has not been previously described. We report a case of an 89-year-old woman with a known 9-cm AAA, which was diagnosed in 2003. The patient had refused any kind of treatment at that time. Recent imaging studies obtained 7 years later revealed an AAA of 4 cm diameter. This is the first recorded case of significant spontaneous AAA sac shrinkage. PMID:21444348

  20. Mycotic aneurysm of the aortic arch.

    PubMed

    Aliaga, L; Cobo, F; Miranda, C; Lara, J

    2000-01-01

    A 61-year-old diabetic woman presented with a mycotic aneurysm of the aortic arch, also involving the left subclavian and vertebral arteries, caused by Staphylococcus aureus. Two months before, she had suffered from staphylococcal septic arthritis in her left knee. The patient was treated with antibiotics and an emergency operation was performed involving aneurysm excision and in situ synthetic graft replacement. She died on the fourth postoperative day from hemorrhagic shock. PMID:10961533

  1. Advances in the diagnosis of acute aortic syndromes: Role of imaging techniques.

    PubMed

    Ciccone, Marco Matteo; Dentamaro, Ilaria; Masi, Filippo; Carbonara, Santa; Ricci, Gabriella

    2016-06-01

    Aortic diseases include a wide range of pathological conditions: aortic aneurysms, pseudoaneurysms, acute aortic syndromes, atherosclerotic and inflammatory conditions, genetic diseases and congenital anomalies. Acute aortic syndromes have acute onset and may be life-threatening. They include aortic dissection, intramural haematoma, penetrating aortic ulcer and traumatic aortic injury. Pain is the common denominator to all acute aortic syndromes. Pain occurs regardless of age, gender and other associated clinical conditions. In this review, we deal with the main findings in the clinical setting and the most recent indications for diagnostic imaging, which are aimed to start an appropriate treatment and improve the short- and long-term prognosis of these patients. PMID:26957573

  2. Bicuspid Aortic Stenosis Treated With the Repositionable and Retrievable Lotus Valve.

    PubMed

    Seeger, Julia; Gonska, Birgid; Rodewald, Christoph; Rottbauer, Wolfgang; Wöhrle, Jochen

    2016-01-01

    Transcatheter aortic valve implantation (TAVI) for severe aortic stenosis is a well-established and safe therapeutic option. However, data on TAVI in bicuspid aortic valve stenosis are limited and show a higher rate of moderate-severe aortic regurgitation compared with TAVI for tricuspid aortic valve stenosis. We report for the first time, to our knowledge, the use of the mechanically deployed Lotus valve in bicuspid aortic stenosis. In our patient who had severe bicuspid aortic stenosis and was at high surgical risk, the implantation of the repositionable and completely retrievable Lotus valve was a safe and controlled procedure resulting in no relevant aortic regurgitation. PMID:26604121

  3. Supramolecular Archimedean Cages Assembled with 72 Hydrogen Bonds

    SciTech Connect

    Liu, Yuzhou; Hu, Chunhua; Comotti, Angiolina; Ward, Michael D.

    2011-12-09

    Self-assembly of multiple components into well-defined and predictable structures remains one of the foremost challenges in chemistry. Here, we report on the rational design of a supramolecular cage assembled from 20 ions of three distinct species through 72 hydrogen bonds. The cage is constructed from two kinds of hexagonal molecular tiles, a tris(guanidinium)nitrate cluster and a hexa(4-sulfonatophenyl)benzene, joined at their edges through complementary and metrically matched N-H {hor_ellipsis} O-S hydrogen bonds to form a truncated octahedron, one of the Archimedean polyhedra. The truncated octahedron, with an interior volume of 2200 cubic angstroms, serves as the composite building unit of a body-centered cubic zeolite-like framework, which exhibits an ability to encapsulate a wide range of differently charged species, including organic molecules, transition metal complexes, and 'ship-in-a-bottle' nanoclusters not observed otherwise.

  4. Cages and anomalous diffusion in vibrated dense granular media.

    PubMed

    Scalliet, Camille; Gnoli, Andrea; Puglisi, Andrea; Vulpiani, Angelo

    2015-05-15

    A vertically shaken granular medium hosts a blade rotating around a fixed vertical axis, which acts as a mesorheological probe. At high densities, independently of the shaking intensity, the blade's dynamics shows strong caging effects, marked by transient subdiffusion and a maximum in the velocity power density spectrum, at a resonant frequency ~10 Hz. Interpreting the data through a diffusing harmonic cage model allows us to retrieve the elastic constant of the granular medium and its collective diffusion coefficient. For high frequencies f, a tail ~1/f in the velocity power density spectrum reveals nontrivial correlations in the intracage microdynamics. At very long times (larger than 10 s), a superdiffusive behavior emerges, ballistic in the most extreme cases. Consistently, the distribution of slow velocity inversion times τ displays a power-law decay, likely due to persistent collective fluctuations of the host medium. PMID:26024199

  5. Engineering Porous Organic Cage Crystals with Increased Acid Gas Resistance.

    PubMed

    Zhu, Guanghui; Hoffman, Christopher D; Liu, Yang; Bhattacharyya, Souryadeep; Tumuluri, Uma; Jue, Melinda L; Wu, Zili; Sholl, David S; Nair, Sankar; Jones, Christopher W; Lively, Ryan P

    2016-07-25

    Both known and new CC3-based porous organic cages are prepared and exposed to acidic SO2 in vapor and liquid conditions. Distinct differences in the stability of the CC3 cages exist depending on the chirality of the diamine linkers used. The acid catalyzed CC3 degradation mechanism is probed via in situ IR and a degradation pathway is proposed and supported with computational results. CC3 crystals synthesized with racemic mixtures of diaminocyclohexane exhibited enhanced stability compared to CC3-R and CC3-S. Confocal fluorescent microscope images reveal that the stability difference in CC3 species originates from an abundance of mesoporous grain boundaries in CC3-R and CC3-S, allowing facile access of aqueous SO2 throughout the crystal, promoting decomposition. These grain boundaries are absent from CC3 crystals made with racemic linkers. PMID:27253350

  6. Spatiotemporal control of embryonic gene expression using caged morpholinos.

    PubMed

    Shestopalov, Ilya A; Chen, James K

    2011-01-01

    Embryonic development depends on spatial and temporal control of gene function, and deciphering the molecular mechanisms that underlie pattern formation requires methods for perturbing gene expression with similar precision. Emerging chemical technologies can enable such perturbations, as exemplified by the use of caged morpholino (cMO) oligonucleotides to photo-inactivate genes in zebrafish embryos with spatiotemporal control. This chapter describes general principles for cMO design and methods for cMO assembly in three steps from commercially available reagents. Experimental techniques for the microinjection and photoactivation of these reagents are described in detail, as well as the preparation and application of caged fluorescein dextran (cFD) for labeling irradiated cells. Using these protocols, cMOs can be effective tools for functional genomic studies in zebrafish and other model organisms. PMID:21924162

  7. Optical triggered seizures using a caged 4-Aminopyridine

    PubMed Central

    Zhao, Mingrui; McGarry, Laura M.; Ma, Hongtao; Harris, Samuel; Berwick, Jason; Yuste, Rafael; Schwartz, Theodore H.

    2015-01-01

    Animal models of epilepsy are critical not only for understanding the fundamental mechanism of epilepsy but also for testing the efficacy of new antiepileptic drugs and novel therapeutic interventions. Photorelease of caged molecules is widely used in biological research to control pharmacologic events with high spatio-temporal resolution. We developed a technique for in vivo optical triggering of neocortical seizures using a novel caged compound based on ruthenium photochemistry (RuBi-4AP). Epileptiform events in mouse cortex were induced with blue light in both whole brain and focal illumination. Multi-electrode array recording and optical techniques were used to characterize the propagation of these epileptic events, including interictal spikes, polyspikes, and ictal discharges. These results demonstrate a novel optically-triggered seizure model, with high spatio-temporal control, that could have widespread application in the investigation of ictal onset, propagation and to develop novel light-based therapeutic interventions. PMID:25698919

  8. Hybrid uranium-transition-metal oxide cage clusters.

    PubMed

    Ling, Jie; Hobbs, Franklin; Prendergast, Steven; Adelani, Pius O; Babo, Jean-Marie; Qiu, Jie; Weng, Zhehui; Burns, Peter C

    2014-12-15

    Transition-metal based polyoxometalate clusters have been known for decades, whereas those built from uranyl peroxide polyhedra have more recently emerged as a family of complex clusters. Here we report the synthesis and structures of six nanoscale uranyl peroxide cage clusters that contain either tungstate or molybdate polyhedra as part of the cage, as well as phosphate tetrahedra. These transition-metal-uranium hybrid clusters exhibit unique polyhedral connectivities and topologies that include 6-, 7-, 8-, 10-, and 12-membered rings of uranyl polyhedra and uranyl ions coordinated by bidentate peroxide in both trans and cis configurations. The transition-metal polyhedra appear to stabilize unusual units built of uranyl polyhedra, rather than templating their formation. PMID:25434424

  9. Battery with modular air cathode and anode cage

    DOEpatents

    Niksa, Marilyn J.; Pohto, Gerald R.; Lakatos, Leslie K.; Wheeler, Douglas J.; Niksa, Andrew J.; Schue, Thomas J.; Turk, Thomas R.

    1988-01-01

    A battery assembly of the consumable metal anode type has now been constructed for ready assembly as well as disassembly. In a non-conductive and at least substantially inert cell body, space is provided for receiving an open-structured, non-consumable anode cage. The cage has an open top for facilitating insertion of an anode. A modular cathode is used, comprising a peripheral current conductor frame clamped about a grid reinforced air cathode in sheet form. The air cathode may be double gridded. The cathode frame can be sealed, during assembly, with electrolyte-resistant-sealant as well as with adhesive. The resulting cathode module can be assembled outside the cell body and readily inserted therein, or can later be easily removed therefrom.

  10. Battery with modular air cathode and anode cage

    DOEpatents

    Niksa, Marilyn J.; Pohto, Gerald R.; Lakatos, Leslie K.; Wheeler, Douglas J.; Niksa, Andrew J.; Schue, Thomas J.

    1987-01-01

    A battery assembly of the consumable metal anode type has now been constructed for ready assembly as well as disassembly. In a non-conductive and at least substantially inert cell body, space is provided for receiving an open-structured, non-consumable anode cage. The cage has an open top for facilitating insertion of an anode. A modular cathode is used, comprising a peripheral current conductor frame clamped about a grid reinforced air cathode in sheet form. The air cathode may be double gridded. The cathode frame can be sealed, during assembly, with electrolyte-resistant-sealant as well as with adhesive. The resulting cathode module can be assembled outside the cell body and readily inserted therein, or can later be easily removed therefrom.

  11. Lanthanides caged by the organic chelates; structural properties

    NASA Astrophysics Data System (ADS)

    Smentek, Lidia

    2011-04-01

    The structure, in particular symmetry, geometry and morphology of organic chelates coordinated with the lanthanide ions are analyzed in the present review. This is the first part of a complete presentation of a theoretical description of the properties of systems, which are widely used in technology, but most of all, in molecular biology and medicine. The discussion is focused on the symmetry and geometry of the cages, since these features play a dominant role in the spectroscopic activity of the lanthanides caged by organic chelates. At the same time, the spectroscopic properties require more formal presentation in the language of Racah algebra, and deserve a separate analysis. In addition to the parent systems of DOTA, DOTP, EDTMP and CDTMP presented here, their modifications by various antennas are analyzed. The conclusions that have a strong impact upon the theory of the energy transfer and the sensitized luminescence of these systems are based on the results of numerical density functional theory calculations.

  12. Rotational Brownian Dynamics simulations of clathrin cage formation

    SciTech Connect

    Ilie, Ioana M.; Briels, Wim J.; Otter, Wouter K. den

    2014-08-14

    The self-assembly of nearly rigid proteins into ordered aggregates is well suited for modeling by the patchy particle approach. Patchy particles are traditionally simulated using Monte Carlo methods, to study the phase diagram, while Brownian Dynamics simulations would reveal insights into the assembly dynamics. However, Brownian Dynamics of rotating anisotropic particles gives rise to a number of complications not encountered in translational Brownian Dynamics. We thoroughly test the Rotational Brownian Dynamics scheme proposed by Naess and Elsgaeter [Macromol. Theory Simul. 13, 419 (2004); Naess and Elsgaeter Macromol. Theory Simul. 14, 300 (2005)], confirming its validity. We then apply the algorithm to simulate a patchy particle model of clathrin, a three-legged protein involved in vesicle production from lipid membranes during endocytosis. Using this algorithm we recover time scales for cage assembly comparable to those from experiments. We also briefly discuss the undulatory dynamics of the polyhedral cage.

  13. Cages and Anomalous Diffusion in Vibrated Dense Granular Media

    NASA Astrophysics Data System (ADS)

    Scalliet, Camille; Gnoli, Andrea; Puglisi, Andrea; Vulpiani, Angelo

    2015-05-01

    A vertically shaken granular medium hosts a blade rotating around a fixed vertical axis, which acts as a mesorheological probe. At high densities, independently of the shaking intensity, the blade's dynamics shows strong caging effects, marked by transient subdiffusion and a maximum in the velocity power density spectrum, at a resonant frequency ˜10 Hz . Interpreting the data through a diffusing harmonic cage model allows us to retrieve the elastic constant of the granular medium and its collective diffusion coefficient. For high frequencies f , a tail ˜1 /f in the velocity power density spectrum reveals nontrivial correlations in the intracage microdynamics. At very long times (larger than 10 s), a superdiffusive behavior emerges, ballistic in the most extreme cases. Consistently, the distribution of slow velocity inversion times τ displays a power-law decay, likely due to persistent collective fluctuations of the host medium.

  14. Modelling of current loads on aquaculture net cages

    NASA Astrophysics Data System (ADS)

    Kristiansen, Trygve; Faltinsen, Odd M.

    2012-10-01

    In this paper we propose and discuss a screen type of force model for the viscous hydrodynamic load on nets. The screen model assumes that the net is divided into a number of flat net panels, or screens. It may thus be applied to any kind of net geometry. In this paper we focus on circular net cages for fish farms. The net structure itself is modelled by an existing truss model. The net shape is solved for in a time-stepping procedure that involves solving a linear system of equations for the unknown tensions at each time step. We present comparisons to experiments with circular net cages in steady current, and discuss the sensitivity of the numerical results to a set of chosen parameters. Satisfactory agreement between experimental and numerical prediction of drag and lift as function of the solidity ratio of the net and the current velocity is documented.

  15. Jamming vs Caging in Three Dimensional Jamming Percolation

    NASA Astrophysics Data System (ADS)

    Shokef, Yair; Segall, Nimrod; Teomy, Eial

    We study a three-dimensional kinetically-constrained lattice-gas model, in which the ability of a particle to move depends on the occupation of neighboring sites in an orientational manner. The kinetic rules are constructed such that chains of permanently-frozen particles reach an infinite length at the critical density of directed percolation. Thus at this critical density the system undergoes a jamming transition, above which there is a finite fraction of jammed particles. We demonstrate that the three-dimensional mesh-like structure of the one-dimensional jammed chains enables the free particles to propagate through the holes in this mesh. This diffusive motion is terminated at a second critical density above which all particles are caged. The largest and second largest clusters of dynamically-connected sites exhibit singularities at both densities. Thus our model assists in separating between the two distinct phenomena of jamming and caging.

  16. Characterizing caged molecules through flash photolysis and transient absorption spectroscopy.

    PubMed

    Kao, Joseph P Y; Muralidharan, Sukumaran

    2013-01-01

    Caged molecules are photosensitive molecules with latent biological activity. Upon exposure to light, they are rapidly transformed into bioactive molecules such as neurotransmitters or second messengers. They are thus valuable tools for using light to manipulate biology with exceptional spatial and temporal resolution. Since the temporal performance of the caged molecule depends critically on the rate at which bioactive molecules are generated by light, it is important to characterize the kinetics of the photorelease process. This is accomplished by initiating the photoreaction with a very brief but intense pulse of light (i.e., flash photolysis) and monitoring the course of the ensuing reactions through various means, the most common of which is absorption spectroscopy. Practical guidelines for performing flash photolysis and transient absorption spectroscopy are described in this chapter. PMID:23494372

  17. Transcaval Aortic Access for Percutaneous Thoracic Aortic Aneurysm Repair: Initial Human Experience

    PubMed Central

    Uflacker, Andre; Lim, Scott; Ragosta, Michael; Haskal, Ziv J; Lederman, Robert J.; Kern, John; Upchurch, Gilbert; Huber, Timothy; Angle, John F.; Ailawadi, Gorav

    2015-01-01

    Transcaval aortic access has been used for deployment of transcatheter aortic valves in patients in whom conventional arterial approaches are not feasible. The present report describes its use for thoracic endovascular aortic repair (TEVAR) in a 61-year-old man with a descending thoracic aneurysm. Transcaval access was performed in lieu of a surgical iliac conduit in view of small atherosclerotic pelvic arteries. TEVAR was successfully performed, followed by intervascular tract occlusion with the use of a ventricular septal occluder. Computed tomography 2 d later demonstrated no extravasation. At 1 mo, the aneurysm was free of endoleaks, the aortocaval tract had healed, and the patient had returned to baseline functional status. PMID:26408210

  18. Thrombocytosis following splenectomy and aortic valve replacement for idiopathic thrombocytopaenic purpura with bicuspid aortic valve

    PubMed Central

    Katiyar, Sarika; Ganjsinghani, Payal Kamlesh; Jain, Rajnish Kumar

    2015-01-01

    Idiopathic thrombocytopaenic purpura (ITP) patients are at high risk for complications during and after cardiac surgeries involving cardiopulmonary bypass. The main clinical problem of primary ITP is an increased risk of bleeding although bleeding may not always be present. More recently, thrombosis has become appreciated as another potential complication of the procedure. We report a 22-year-old female patient with ITP with bicuspid aortic valve and splenomegaly, who underwent uncomplicated aortic valve replacement and splenectomy simultaneously. She was readmitted with chest pain due to coronary thrombosis following splenectomy which made the management difficult. We describe our experience in managing this patient who presented with thrombotic complication rather than bleeding in post-operative period and the challenges met in maintaining appropriate anticoagulation for aortic valve replacement as well as thrombosis, post-splenectomy PMID:26379295

  19. Non coding RNAs in aortic aneurysmal disease

    PubMed Central

    Duggirala, Aparna; Delogu, Francesca; Angelini, Timothy G.; Smith, Tanya; Caputo, Massimo; Rajakaruna, Cha; Emanueli, Costanza

    2015-01-01

    An aneurysm is a local dilatation of a vessel wall which is >50% its original diameter. Within the spectrum of cardiovascular diseases, aortic aneurysms are among the most challenging to treat. Most patients present acutely after aneurysm rupture or dissection from a previous asymptomatic condition and are managed by open surgical or endovascular repair. In addition, patients may harbor concurrent disease contraindicating surgical intervention. Collectively, these factors have driven the search for alternative methods of identifying, monitoring and treating aortic aneurisms using less invasive approaches. Non-coding RNA (ncRNAs) are emerging as new fundamental regulators of gene expression. The small microRNAs have opened the field of ncRNAs capturing the attention of basic and clinical scientists for their potential to become new therapeutic targets and clinical biomarkers for aortic aneurysm. More recently, long ncRNAs (lncRNAs) have started to be actively investigated, leading to first exciting reports, which further suggest their important and yet largely unexplored contribution to vascular physiology and disease. This review introduces the different ncRNA types and focus at ncRNA roles in aorta aneurysms. We discuss the potential of therapeutic interventions targeting ncRNAs and we describe the research models allowing for mechanistic studies and clinical translation attempts for controlling aneurysm progression. Furthermore, we discuss the potential role of microRNAs and lncRNAs as clinical biomarkers. PMID:25883602

  20. Molecular Mechanisms of Thoracic Aortic Dissection

    PubMed Central

    Wu, Darrell; Shen, Ying H.; Russell, Ludivine; Coselli, Joseph S.; LeMaire, Scott A.

    2013-01-01

    Thoracic aortic dissection (TAD) is a highly lethal vascular disease. In many patients with TAD, the aorta progressively dilates and ultimately ruptures. Dissection formation, progression, and rupture cannot be reliably prevented pharmacologically because the molecular mechanisms of aortic wall degeneration are poorly understood. The key histopathologic feature of TAD is medial degeneration, a process characterized by smooth muscle cell depletion and extracellular matrix degradation. These structural changes have a profound impact on the functional properties of the aortic wall and can result from excessive protease-mediated destruction of the extracellular matrix, altered signaling pathways, and altered gene expression. Review of the literature reveals differences in the processes that lead to ascending versus descending and sporadic versus hereditary TAD. These differences add to the complexity of this disease. Although tremendous progress has been made in diagnosing and treating TAD, a better understanding of the molecular, cellular, and genetic mechanisms that cause this disease is necessary to developing more effective preventative and therapeutic treatment strategies. PMID:23856125