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Sample records for aortic caged ball-valve

  1. Echocardiographic features of aortic ball valve prosthesis malfunction.

    PubMed

    Weisburst, M R; Singh, A K; Riley, R S

    1982-11-01

    A case of aortic ball valve prosthesis malfunction is described in which the poppet became alternately stuck in the open and closed position. The patient experienced chest pain followed by pulmonary edema and cardiac arrest. Malfunction of prosthetic valve was diagnosed on echocardiogram and cardiopulmonary resuscitation was carried out until a Bjork-Shiley valve could be inserted in place of the faulty prosthesis. At the time of the operation, poppet migration had occurred and the poppet could not be found. Subsequent Bjork-Shiley aortic valve prosthesis dysfunction was suggested by variation in the intensity of the aortic opening sound and in the duration of the systolic ejection period. Fluoroscopy revealed the missing poppet in the left ventricle. Following surgical removal of the poppet, "normal" Bjork-Shiley valve function was restored.

  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. Ball valve safety screen

    SciTech Connect

    Bolding, B.H.

    1981-09-01

    A device for preventing unwanted objects from entering the ball assembly of a float collar or float shoe and otherwise damaging or plugging the valve mechanism therein is disclosed. The device comprises a screen constructed of expanded metal and rigidly affixed to the interior of the float collar or float shoe above the ball valve assembly. The screen portion is either mounted to the interior surface of the float collar sleeve by an annular structural member or mounted to a structural band which is partially embedded in the concrete portion of the float collar or casing guide shoe.

  6. 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.

  7. 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.

  8. The unnatural history of valvular heart disease: late results with silastic ball valve prostheses.

    PubMed

    Freimanis, I; Starr, A

    1984-01-01

    The development of prosthetic heart valves successfully arrested the dismal natural history of valvular heart disease for thousands of patients. The experiences of numerous investigators provided a setting wherein the design and implantation of the silastic ball valves led to improved survival with both aortic and mitral valve replacement. Refinement of the caged-ball design was based on clinical and laboratory findings. In the mitral position, valve related thromboembolism was reduced from 38% to 3%. With the aortic prostheses the problem of ball variance was overcome by reducing trauma to the poppet and altering its heat curing process. In 1967 a completely cloth covered valve was introduced to reduce further the thromboembolic rate. Significant improvement in the embolus-free rate was ultimately found to be dependent on the year of operation with introduction of the time-frame concept. The current mitral silastic ball valve, Model 6120, yields an actuarial survival of 72 (+/- 3%), 54 (+/- 5%), and 37 (+/- 5%) for five, ten and fifteen years respectively. For aortic valve replacement, current Model 1260, the actuarial survival is 71 (+/- 2%), 58 (+/- 3%) and 48 (+/- 4%) for five, ten and fifteen years respectively. Late results are compared to other valvular prostheses.

  9. 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

  10. 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

  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. Acute tricuspid valve obstruction following the use of tricuspid ball valve prosthesis

    PubMed Central

    Samaan, H. A.; Murali, R.

    1970-01-01

    A case is presented in which the mitral and tricuspid valves were replaced by a ball-valve prosthesis. The patient was admitted as an emergency 18 months later with the clinical picture of acute venous inflow obstruction to the heart due to tricuspid ball-valve prosthesis obstruction. Successful replacement under emergency open heart surgery, using assisted circulation, is described. Images PMID:5452288

  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. 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.

  15. Ball valve design for solid withdrawal service in coal liquefaction

    NASA Astrophysics Data System (ADS)

    Patton, Alexander J.

    1981-02-01

    Valves used for drawdown of the solids produced in the coal liquefaction process must be designed to operate at high temperatures and must prevent the buildup of solids within the valve internals to insure operability. Consideration must also be given to materials used for seating surfaces in terms of being able to withstand abrasion. Research into the design and materials for this application results in a new ball valve design with a special inlet port liner and O-ring seal. A prototype valve was built and put in service in a small scale, experimental coal liquefaction plant. For comparative purposes a standard design valve was also used, with both valves being subjected to over 1000 open/close cycles, after which both valves were removed, tested, and disassembled for inspection. The results of this experimental program will be presented, including process parameters, service conditions, and material evaluation. Particular emphasis will be placed on wear of seating surfaces and the effects of process material on the physical properties of seal and packing materials.

  16. Failure analyses of two ball valves used for coal-gasification applications

    SciTech Connect

    Van Den Avyle, J.A.; Pope, L.E.

    1982-07-01

    Two ball valves which had failed by developing excess leakage were supplied for analyses. The 2'' (51 mm) valve had experienced 5000 cycles during 20 hrs usage in an unknown chemical environment. Wear on the ball and seats was a multi-stage process starting with breakdown of a hard chrome plating on the stainless steel ball. This eventually led to adhesive weld transfer of the stainless steel to the seat made of Stellite 6 alloy. The 6'' (152 mm) ball valve had experienced a cycling test sequence using compressed air up to 300 psig (2.07 MPa) at 850/sup 0/F (727/sup 0/K). Damage was characterized as abrasive wear caused either by particles deposited by the compressed air or by carbide particles present in the Stellite 6 alloy ball and seat hardfacing. The decrease in this alloy's compressive yield strength at the elevated test temperature contributed to increased wear rates.

  17. Metal seated ball valves for the flow control of abrasive fluids

    SciTech Connect

    Harrison, M.J.

    1997-07-01

    Until recent times the only acceptable valves for use in medium to high pressure slurry pipelines had been Knife Gate Valves and Lubricated Plug Valves. Both of these types of valves have their own inherent problems. Knife Gate Valves are limited by operating pressure, temperature limits, seat tightness, ease of operation and automation. Lubricated Plug Valves are limited by the constant need for sealant injection, high maintenance, high cost, elevated temperatures and reduced through-put, due to the rectangular port design. Attempts have been made to utilize modified versions of the traditional oil and gas ball valve for use in abrasive fluids and many manufacturers are capable of producing a metal seated version. This metal seated valve is a modification of a soft seated API 6D trunnion mounted ball valve, designed primarily for water, oil and gas services. This modified valve is comparatively inexpensive and although it can function well with small amounts of solids in the flowing media, it cannot survive the tortures of cycling in medium and high pressure abrasive fluids, or at high differential pressures. This type of valve utilizes a pressure assisted or {open_quotes}dynamic seal{close_quotes} on both sides of the ball. These pressure assisted seals are generally made ineffective by the ingress of solid particles.

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

    SciTech Connect

    VAN KATWIJK, C.

    2000-06-21

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

  1. Basaloid Squamous Cell Carcinoma: An Unusual Ball-Valve Laryngeal Obstruction

    PubMed Central

    Tan, Sien Hui; Hindi, Khalid W; Chandran, Patricia Ann; Chong, Aun Wee

    2015-01-01

    Introduction: A rare case of basaloid squamous cell carcinoma (BSCC) of the larynx, which has not been previously reported, is described. Case Report: A 60-year-old man was presented to the Otolaryngology Department with progressive dyspnoea and dysphagia to solids for over a period of 1 week. Direct laryngoscopy revealed a tumour at the laryngeal aspect of the epiglottis, which prolapsed into the laryngeal inlet each time the patient inspired. This resulted in an inspiratory stridor despite adequate glottic opening and normal mobility of the vocal cords. Conclusion: Therefore, in cases where a ball-valve lesion causes intermittent life-threatening airway obstruction, BSCC of the larynx, though rare, must be considered as a differential diagnosis. PMID:26082908

  2. A characteristic analysis of high pressure and high temperature 3-way ball valve

    NASA Astrophysics Data System (ADS)

    Lee, Joon Ho; Jeon, Rock Won; Kim, Si Pom; Lee, Jae Hun; Lee, Jae Hoon

    2012-11-01

    Ball valves have been mostly used for high temperature/high pressure valves using in petrochemical carriers and oil tankers being built in Korea, which requires high quality products with confidentiality and durability. As a larger disaster may be generated by leakage of oil or gas from valves, thus the present research applied a numerical analysis method on thermal stress distribution and deformation, etc. In addition, the present research compared the performance test result with numerical analysis results. The Max stress by parts was confirmed through thermal-structural coupled field analysis of major parts to evaluate safety. And its performance was verified by carrying out the durability and leakage test for the manufactured valves.

  3. Transfemoral implantation of CoreValve Evolut-R aortic prosthesis in patient with prior ball-cage mechanical mitral valve prosthesis.

    PubMed

    Maluenda, Gabriel; Caorsi, Carlos; Baeza, Cristian

    2016-06-01

    Transcatheter aortic valve replacement remains challenge in patients with ball-cage-type mechanical valve in mitral position. Potential under-expansion of the percutaneous valve and interaction between the mitral ball-cage mechanical valve tilted towards the left ventricular outflow tract and the percutaneous valve adds risk during and after implantation. We report a successful implantation of the novel CoreValve Evolut-R self-expanding in a patient with severe aortic stenosis and a mitral Starr-Edwards mechanical valve implanted 28years ago.

  4. 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.

  5. [Ball variance and fracture of a Smeloff-Cutter prosthesis 24 years after aortic valve replacement].

    PubMed

    Hust, M H; Klinkmüller, A; Keim, M; Momper, R; Nothwang, G

    1997-07-01

    This report documents a case of ball variance in a Smeloff-Cutter aortic prosthesis occurring 24 years after implantation. After episodes of embolic complications the patient died in acute shock. The silicone rubber ball showed several alterations including discoloration, grooving, cracking, swelling and subtotal fracture of the poppet. Terminal valvular malfunction was caused by complete thrombosis of the prosthesis. In most patients ball variance occurred during the first years after valve replacement; thus, the observed case is a very rare late complication of a ball-valve prosthesis.

  6. Bimetallic cages

    NASA Astrophysics Data System (ADS)

    Fournier, René; Afzal-Hussain, Sabeen

    2013-02-01

    We report the results of density functional theory for 39 clusters AxBy (x + y = 10 or 12) where A and B are metals from group 1, 2, 11, 12, 13, or 14 of the periodic table. The chemical compositions were chosen to satisfy an electronic shell closing criterion. We performed an unbiased search for the global minimum (GM) by taboo search in descriptor space in each case. Eight of the 39 putative GM are cages even though none of the clusters contains gold, a metal with a well known propensity to form cages. These cages are large enough to accommodate a dopant atom with an atomic radius varying between 0.7 Å and 1.2 Å. The chemical compositions most likely to produce cages have an element of group 11 alloyed with an element of group 2, 12, or 13.

  7. Bimetallic cages.

    PubMed

    Fournier, René; Afzal-Hussain, Sabeen

    2013-02-07

    We report the results of density functional theory for 39 clusters A(x)B(y) (x + y = 10 or 12) where A and B are metals from group 1, 2, 11, 12, 13, or 14 of the periodic table. The chemical compositions were chosen to satisfy an electronic shell closing criterion. We performed an unbiased search for the global minimum (GM) by taboo search in descriptor space in each case. Eight of the 39 putative GM are cages even though none of the clusters contains gold, a metal with a well known propensity to form cages. These cages are large enough to accommodate a dopant atom with an atomic radius varying between 0.7 Å and 1.2 Å. The chemical compositions most likely to produce cages have an element of group 11 alloyed with an element of group 2, 12, or 13.

  8. Aortic angiography

    MedlinePlus

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

  9. Aortic Dissection

    MedlinePlus

    ... arteries (atherosclerosis) Weakened and bulging artery (pre-existing aortic aneurysm) An aortic valve defect (bicuspid aortic valve) A ... valve, tell your doctor. If you have an aortic aneurysm, find out how often you need monitoring and ...

  10. Comparison of modified chandler, roller pump, and ball valve circulation models for in vitro testing in high blood flow conditions: application in thrombogenicity testing of different materials for vascular applications.

    PubMed

    van Oeveren, Wim; Tielliu, Ignace F; de Hart, Jurgen

    2012-01-01

    Three different models, a modified Chandler loop, roller pump, and a new ball valve model (Hemobile), were compared with regard to intrinsic damage of blood components and activation of platelets. The Hemobile was used for testing of polymer tubes. High flow was not possible with the Chandler loop. The roller pump and the Hemobile could be adjusted to high flow, but he pump induced hemolysis. Platelet numbers were reduced in the roller pump and Chandler loop (P < 0.05), but remained high in the Hemobile. Platelet aggregation was reduced in all models. The Hemobile was applied for testing vascular graft materials, and allowed different circuits circulated simultaneously at 37°C. ePTFE, Dyneema Purity UHMWPE fiber and PET fiber based tubes, all showed hemolysis below 0.2% and reduced platelet count and function. Binding of fibrin and platelets was higer on PET, inflammatory markers were lowest on Dyneema Purity UHMWPE. We concluded that the Hemobile minimally affects blood and could be adjusted to high blood flows, simulating arterial shear stress. The Hemobile was used to measure hemocompatibility of graft material and showed Dyneema Purity UHMWPE fiber in many ways more hemocompatible than ePTFE and PET.

  11. The performance of the Braunwald-Cutter aortic prosthetic valve.

    PubMed

    Blackstone, E H; Kirklin, J W; Pluth, J R; Turner, M E; Parr, G V

    1977-04-01

    Four hundred seventy-five patients underwent aortic valve replacement with the Braunwald-Cutter ball-valve prosthesis at two institutions. The early (30-day) hospital mortality was 4.7% for those with isolated aortic valve replacement and 6.9% for the entire group. For the former, 5-year actuarial survival of the hospital survivors was 72 +/- 5.7%; for the latter group it was 71 +/- 4.4%. Eleven patients (5 since the date of follow-up inquiry) have suffered poppet escape, 9 of whom died. The actuarial incidence of known poppet escape is 4 +/- 2.6% at 47 months; when the 5 patients suffering poppet escape since the date of follow-up inquiry are included, with certain assumptions, the incidence is 3.7 +/- 1.14%. The projected probability of poppet escape using all 11 patients is 12.2% at 5 years; the 70% confidence bands of projected probability of poppet escape separate from those of the risk of re-replacement at 61 months. This and other analyses indicate that in general, patients with the Braunwald-Cutter aortic prosthesis should have it replaced 4 1/2 to 5 years after its insertion.

  12. Aortic dissection

    MedlinePlus

    Aortic aneurysm - dissecting; Chest pain - aortic dissection; Thoracic aortic aneurysm - dissection ... also cause abnormal widening or ballooning of the aorta ( aneurysm ). The exact cause is unknown, but more common ...

  13. 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 ...

  14. Ten year clinical evaluation of Starr-Edwards 2400 and 1260 aortic valve prostheses.

    PubMed Central

    Hackett, D; Fessatidis, I; Sapsford, R; Oakley, C

    1987-01-01

    The long term performance characteristics of the 2400 and 1260 series of Starr-Edwards aortic prostheses were investigated by a follow up study of clinical outcome of 327 patients discharged from hospital with isolated aortic valve replacement. Follow up lasted for up to 10 years and was based on 1616 patient-years. The 2400 series cloth covered tracked valve was implanted in 182 patients from 1974 to 1980 and the 1260 series bare strut silastic ball valve was inserted in 145 patients from 1979 to 1983. Total 10 year mortality and valve related morbidity were low and no cases of mechanical valve failure were recorded. There were no significant actuarial differences in mortality or valve related morbidity between the 2400 and 1260 valves. Starr-Edwards models 2400 and 1260 aortic valve prostheses showed excellent durability without any mechanical failures over a 10 year period. The long term outcome of isolated aortic valve replacement with these models is associated with a low frequency of valve related complications. PMID:3580223

  15. Flow Cage Assemblies

    NASA Technical Reports Server (NTRS)

    Sherrit, Stewart (Inventor); Badescu, Mircea (Inventor); Bao, Xiaoqi (Inventor); Bar-Cohen, Yoseph (Inventor)

    2017-01-01

    Apparatus, systems and methods for implementing flow cages and flow cage assemblies in association with high pressure fluid flows and fluid valves are provided. Flow cages and flow assemblies are provided to dissipate the energy of a fluid flow, such as by reducing fluid flow pressure and/or fluid flow velocity. In some embodiments the dissipation of the fluid flow energy is adapted to reduce erosion, such as from high-pressure jet flows, to reduce cavitation, such as by controllably increasing the flow area, and/or to reduce valve noise associated with pressure surge.

  16. Three-dimensional visualization of axial velocity profiles downstream of six different mechanical aortic valve prostheses, measured with a hot-film anemometer in a steady state flow model.

    PubMed

    Hasenkam, J M; Westphal, D; Reul, H; Gormsen, J; Giersiepen, M; Stodkilde-Jorgensen, H; Paulsen, P K

    1987-01-01

    Hot-film anemometry was used for in vitro steady-state measurements downstream of six mechanical aortic valve prostheses at flow rates 10, 20 and 30 l.min-1. Three-dimensional visualizations of velocity profiles at two downstream levels were made with the valves rotated 0 and 60 degrees in relation to the sinuses of valsalvae. The velocity fields downstream of the disc valves were generally skew with increasing velocity gradients and laminar shear stresses with increasing flow rates. Furthermore, increased skewness of the velocity profiles was noticed when the major orifices of the disc valves were towards the commissure than when approaching a sinus of valsalvae. The velocity profiles downstream of the ball valve were generally flat but with considerably more disturbed flow, consistent with the findings in turbulent flow.

  17. 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…

  18. 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…

  19. Anaesthetic management of a patient with a descending thoracic aortic aneurysm and severe bilateral bullous pulmonary parenchymal disease.

    PubMed

    Eagle, C; Tang, T

    1995-02-01

    The anaesthetic management of the surgical repair of a descending aortic aneurysm in a patient with large, bilateral, pulmonary bullae is described. Anaesthesia for descending aortic surgery normally involves unilateral, positive-pressure ventilation, an option which poses some risk of barotrauma in the presence of bilateral bullae. Patients with bullous disease commonly have severe lung disease and thorough preoperative assessment and preparation are necessary. Intraoperatively, bilateral rupture of the bullae could be catastrophic and preparations should be made for this possibility. In order to diminish this risk, a surgical technique including preemptive collapse of the bulla by minithoracotomy and tube drainage, with use of a bronchial blocker to the affected part of the lung may be used. If rupture occurs, then high frequency jet ventilation may be effective. Use of a double lumen endobronchial tube may be advantageous for patients with either unilateral and bilateral bullae. Anaesthesia for patients with bullae should avoid positive-pressure ventilation and nitrous oxide in order to limit the risk of barotrauma from a ball valve mechanism. In this case, the risk of barotrauma was reduced by performing an inhalational induction of anaesthesia and limiting peak inflation pressures during thoracotomy. It was elected to use positive-pressure ventilation through a double lumen endobronchial tube following chest incision. A high frequency jet ventilator was available but not employed. Anaesthetic management was complicated by the presence of pleural adhesions, surgical approach directly through a bulla, and the requirement for one lung ventilation.

  20. [Aortic dissection].

    PubMed

    Ogino, Hitoshi

    2011-07-01

    Acute aortic dissection suddenly occurrs and results in a variety of catastrophic sequelae including cardiac tamponade, rupture, and organ malperfusion. In acute stage (< 2 weeks), according to the classifications on the region of aortic dissection, the condition of the false channel and the onset, appropriate medical, surgical, or endovascular treatments including endovascular aneurysm repair followed by the rapid and accurate diagnosis of aortic dissection using computed tomography and ultrasound should be performed without delay. In the chronic stage (> 2 weeks), the behavior of the chronic dissection or residual distal dissection after the initial treatment should be followed-up carefully with best medical treatment at the regular intervals. If necessary, appropriate surgical and endovascular treatment should be carried out in the proper timing before rupture.

  1. Interpenetrated Cage Structures.

    PubMed

    Frank, Marina; Johnstone, Mark D; Clever, Guido H

    2016-09-26

    This Review covers design strategies, synthetic challenges, host-guest chemistry, and functional properties of interlocked supramolecular cages. Some dynamic covalent organic structures are discussed, as are selected examples of interpenetration in metal-organic frameworks, but the main focus is on discrete coordination architectures, that is, metal-mediated dimers. Factors leading to interpenetration, such as geometry, flexibility and chemical makeup of the ligands, coordination environment, solvent effects, and selection of suitable counter anions and guest molecules, are discussed. In particular, banana-shaped bis-pyridyl ligands together with square-planar metal cations have proven to be suitable building blocks for the construction of interpenetrated double-cages obeying the formula [M4 L8 ]. The peculiar topology of these double-cages results in a linear arrangement of three mechanically coupled pockets. This allows for the implementation of interesting guest encapsulation effects such as allosteric binding and template-controlled selectivity. In stimuli-responsive systems, anionic triggers can toggle the binding of neutral guests or even induce complete structural conversions. The increasing structural and functional complexity in this class of self-assembled hosts promises the construction of intelligent receptors, novel catalytic systems, and functional materials. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. [Aortic aneurysm].

    PubMed

    Villar, Fernando; Pedro-Botet, Juan; Vila, Ramón; Lahoz, Carlos

    2013-01-01

    Aortic aneurysm is one important cause of death in our country. The prevalence of abdominal aortic aneurism (AAA) is around 5% for men older than 50 years of age. Some factors are associated with increased risk for AAA: age, hypertension, hypercholesterolemia, cardiovascular disease and, in particular, smoking. The medical management of patients with an AAA includes cardiovascular risk treatment, particularly smoking cessation. Most of major societies guidelines recommend ultrasonography screening for AAA in men aged 65 to 75 years who have ever smoked because it leads to decreased AAA-specific mortality. Copyright © 2013 Elsevier España, S.L. y SEA. All rights reserved.

  3. 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

  4. Aortic Valve Regurgitation

    MedlinePlus

    ... valve. Also, a narrowing of the aortic valve (aortic stenosis) can be associated with leaking. High blood pressure (hypertension). High blood pressure may stretch the root of the aorta where the aortic valve sits. The valve flaps ( ...

  5. Thoracic aortic aneurysm

    MedlinePlus

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

  6. 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.

  7. Aortic Stenosis.

    PubMed

    Bakaeen, Faisal G; Rosengart, Todd K; Carabello, Blase A

    2017-01-03

    This issue provides a clinical overview of aortic stenosis, focusing on screening, diagnosis, treatment, and practice improvement. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers.

  8. 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.

  9. Faraday Cage Protects Against Lightning

    NASA Technical Reports Server (NTRS)

    Jafferis, W.; Hasbrouck, R. T.; Johnson, J. P.

    1992-01-01

    Faraday cage protects electronic and electronically actuated equipment from lightning. Follows standard lightning-protection principles. Whether lightning strikes cage or cables running to equipment, current canceled or minimized in equipment and discharged into ground. Applicable to protection of scientific instruments, computers, radio transmitters and receivers, and power-switching equipment.

  10. CAGE — EDRN Public Portal

    Cancer.gov

    Promoter hypermethylation of the CAGE1 gene is related to plays a crucial role during the phenotypical morphogenesis of several types of cancer. CAGE1 shows testis-specific expression in normal tissues, but wide expression among cancer tissues and cell lines.

  11. Cryogenic Caging for Science Instrumentation

    NASA Technical Reports Server (NTRS)

    Penanen, Konstantin; Chui, Talso C.

    2011-01-01

    A method has been developed for caging science instrumentation to protect from pyro-shock and EDL (entry, descent, and landing) acceleration damage. Caging can be achieved by immersing the instrument (or its critical parts) in a liquid and solidifying the liquid by cooling. After the launch shock and/or after the payload has landed, the solid is heated up and evaporated.

  12. 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…

  13. ExCage.

    PubMed

    Dale, Edward J; Vermeulen, Nicolaas A; Thomas, Andy A; Barnes, Jonathan C; Juríček, Michal; Blackburn, Anthea K; Strutt, Nathan L; Sarjeant, Amy A; Stern, Charlotte L; Denmark, Scott E; Stoddart, J Fraser

    2014-07-30

    Cyclophanes, especially those where pyridinium units in conjugation with each other are linked up face-to-face within platforms that are held approximately 7 Å apart by rigid linkers, are capable of forming inclusion complexes with polycyclic aromatic hydrocarbons (PAHs) with high binding affinities as a result of a combination of noncovalent bonding interactions, including face-to-face [π···π] stacking and orthogonal [C-H···π] interactions. Here, we report the template-directed, catalyst-assisted synthesis of a three-fold symmetric, extended pyridinium-based, cage-like host (ExCage(6+)) containing a total of six π-electron-deficient pyridinium units connected in a pairwise fashion by three bridging p-xylylene linkers, displayed in a trigonal (1,3,5) fashion around two opposing and parallel 1,3,5-tris(4-pyridinium)benzene platforms. The association constants (K(a)) of eight complexes have been measured by isothermal titration calorimetry (ITC) in acetonitrile and were found to span the range from 2.82 × 10(3) for naphthalene up to 5.5 × 10(6) M(-1) for perylene. The barriers to decomplexation, which were measured in DMF-d7 for phenanthrene, pyrene, triphenylene, and coronene by dynamic (1)H NMR spectroscopy undergo significant stepwise increases from 11.8 → 13.6 → 15.5 → >18.7 kcal mol(-1), respectively, while complexation experiments using rapid injection (1)H NMR spectroscopy in DMF-d7 at -55 °C revealed the barriers to complexation for pyrene and coronene to be 6.7 and >8 kcal mol(-1), respectively. The kinetic and thermodynamic data reveal that, in the case of ExCage(6+), while the smaller PAHs form complexes faster than the larger ones, the larger PAHs form stronger complexes than the smaller ones. It is also worthy of note that, as the complexes become stronger in the case of the larger and larger PAHs, the Rebek 55% solution formula for molecular recognition in the liquid state becomes less and less relevant.

  14. Late ball variance with the Model 1000 Starr-Edwards aortic valve prosthesis. Risk analysis and strategy of operative management.

    PubMed

    Grunkemeier, G L; Starr, A

    1986-06-01

    The first generation of aortic ball-valve prostheses, used until 1965, was associated with poppet damage owing to fatty infiltration of the silicone rubber ball, a phenomenon termed ball variance. For the Model 1000 Starr-Edwards valves, almost all cases were discovered before 8 years. However, a review of our patients still at risk with the original valve and poppet, prompted by other recent reports of late ball variance, has shown that severe variance can exist up to 20 years after implantation. There is a relationship between the year of valve implantation and the timing and severity of ball variance for the overall series of patients surviving operation, but for the subgroup currently at risk the sample sizes are too small to detect any difference, if one still exists. Only three of 12 patients in the current subset were found to have severe variance. Simple ball change has been the operation of choice. Prophylactic reoperation is not indicated in the current subset, but patients require careful follow-up and should be considered for reoperation should symptoms develop.

  15. Rodent Cage Allocation | Center for Cancer Research

    Cancer.gov

    CCR Animal Cage Allocation Principles - 2017 Rodent cage allocations for each principal investigator (PI) are based on: Animal study design and justification BSC Recommendations Package for new tenure track or tenured investigator Average cage usage in previous fiscal years Note: The allocations largely reflect PI requirements for standard mouse caging.

  16. 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

  17. 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. ...

  18. Abdominal aortic aneurysm

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/000162.htm Abdominal aortic aneurysm To use the sharing features on this page, ... to the abdomen, pelvis, and legs. An abdominal aortic aneurysm occurs when an area of the aorta becomes ...

  19. CT in aortic trauma

    SciTech Connect

    Heiberg, E.; Wolverson, M.K.; Sundaram, M.; Shields, J.B.

    1983-06-01

    A diagnosis of aortic transection was made at computed tomography (CT) in four of 10 patients with acute multiple trauma suspected of having thoracic aortic injuries. There were no false-negative or false-positive examinations. The CT findings of an injured aorta were (1) false aneurysm, (2) linear lucency within the opacified aortic lumen caused by the torn edge of the aortic wall, (3) marginal irregularity of the opacified aortic lumen, (4) periaortic or intramural aortic hematoma, and (5) dissection. The extent of associated mediastinal hemorrhage and the amount of blood in the pleural space were not useful as indicators of aortic injury. Similarly, shift of the trachea and esophagus or absence thereof was found in patients with or without aortic tear.

  20. Aortic dissection (image)

    MedlinePlus

    Aortic dissection is a condition in which there is bleeding into and along the wall of the aorta (the ... the inner wall of the artery. Although aortic dissection can affect anybody, it is most often seen ...

  1. Abdominal Aortic Aneurysm (AAA)

    MedlinePlus

    ... Professions Site Index A-Z Abdominal Aortic Aneurysm (AAA) Abdominal aortic aneurysm (AAA) occurs when atherosclerosis or plaque buildup causes the ... weak and bulge outward like a balloon. An AAA develops slowly over time and has few noticeable ...

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

    USDA-ARS?s Scientific Manuscript database

    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...

  3. 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.

  4. 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.

  5. 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.

  6. Transcatheter aortic valve replacement

    MedlinePlus

    ... fully will restrict blood flow. This is called aortic stenosis. If there is also a leak, it is ... TAVR is used for people with severe aortic stenosis who aren't ... valve . In adults, aortic stenosis usually occurs due to calcium ...

  7. Triply interlocked covalent organic cages.

    PubMed

    Hasell, Tom; Wu, Xiaofeng; Jones, James T A; Bacsa, John; Steiner, Alexander; Mitra, Tamoghna; Trewin, Abbie; Adams, Dave J; Cooper, Andrew I

    2010-09-01

    Interlocked molecules comprise two or more separate components that are joined by 'mechanical' rather than covalent bonds. In other words, these molecular assemblies cannot be dissociated without the cleavage of one or more chemical bonds. Although recent progress has enabled the preparation of such topologies through coordination or templating interactions, three-dimensional interlocked covalent architectures remain difficult to prepare. Here, we present a template-free one-pot synthesis of triply interlocked organic cages. These 20-component dimers consist of two tetrahedral monomeric cages each built from four nodes and six linkers. The monomers exhibit axial chirality, which is recognized by their partner cage during the template-free interlocking assembly process. The dimeric cages also include two well-defined cavities per assembly, which for one of the systems studied led to the formation of a supramolecular host-guest chain. These interlocked organic molecules may prove useful as part of a toolkit for the modular construction of complex porous solids and other supramolecular assemblies.

  8. 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…

  9. 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…

  10. 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…

  11. Transcatheter aortic valve implantation.

    PubMed

    Oliemy, Ahmed; Al-Attar, Nawwar

    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.

  12. 50 CFR 648.75 - Cage identification.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 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 ocean...)(2). (h) Presumptions. Surf clams and ocean quahogs found in cages without a valid state tag are...

  13. Novel RDX-Based Cage and Cage-Like Nitramines

    NASA Astrophysics Data System (ADS)

    Türker, Lemi; Çelik Bayar, Çağlar; Turhan, Hamza

    2013-10-01

    1,3,5-Trinitroperhydro-1,3,5-triazine (RDX)-based cage and cage-like nitramines in which two RDX molecules are linked to each other via three and two carbon atoms, respectively, have been investigated computationally using density functional theory (DFT) at a B3LYP/6-31G(d,p) theoretical level. The study focused on finding out how the quantum chemical and detonation properties of RDX change if two RDX molecules come together and form these structures. Both considered nitramines exhibited higher heats of formation (calculated via both PM3 and isodesmic methods) and Kamlet-Jacobs detonation performances and were found to be more sensitive than the reference compounds RDX and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX).

  14. The Effect of Cervical Interbody Cage Morphology, Material Composition, and Substrate Density on Cage Subsidence.

    PubMed

    Suh, Paul B; Puttlitz, Christian; Lewis, Chad; Bal, B Sonny; McGilvray, Kirk

    2017-02-01

    Interbody cages used in spinal fusion surgery can subside into the adjacent vertebral bodies after implantation, leading to loss of spinal height, malalignment, and possible radicular symptoms. Several factors may contribute to cage subsidence. This in vitro investigation examined the possible contribution of substrate density, cage contact area (ie, cage footprint), cage filling, cage end plate surface texture, and cage material composition on the magnitude of subsidence. Commercially available cervical interbody cages of two sizes (16 × 12 mm and 17 × 14 mm) were implanted between foam blocks of two different densities and were cyclically loaded. Cages were made of titanium alloy (Ti4Al6V), silicon nitride ceramic (Si3N4), or polyether ether ketone (n = 8 cages of each material type). Additional testing was performed on Si3N4 cages of the smaller size with nontextured surfaces and with filled cores. Subsidence measurements showed that lower foam density had the greatest influence on subsidence, followed by smaller cage footprint. Cage material had no effect on subsidence. In the additional testing of small-footprint Si3N4 cages, the cages in which the core was filled with a load-bearing porous material had less subsidence in lower-density foam than the cages with an empty core had, whereas cage end plate surface texture had no effect on subsidence. Ranking of the relative impact of these factors indicated that substrate density had the greatest contribution to the measured subsidence (approximately 1.7 times and approximately 67 times greater than the contributions of cage footprint area and material, respectively). The contribution of cage footprint area to subsidence was found to be 40 times greater than the contribution of cage material to subsidence.

  15. Supravalvular aortic stenosis in adult with anomalies of aortic arch vessels and aortic regurgitation

    PubMed Central

    Valente, Acrisio Sales; Alencar, Polyanna; Santos, Alana Neiva; Lobo, Roberto Augusto de Mesquita; de Mesquita, Fernando Antônio; Guimarães, Aloyra Guedis

    2013-01-01

    The supravalvular aortic stenosis is a rare congenital heart defect being very uncommon in adults. We present a case of supravalvular aortic stenosis in adult associated with anomalies of the aortic arch vessels and aortic regurgitation, which was submitted to aortic valve replacement and arterioplasty of the ascending aorta with a good postoperative course. PMID:24598962

  16. Aortic valve surgery - minimally invasive

    MedlinePlus

    ... of the heart is reduced. This is called aortic stenosis. The aortic valve can be replaced using: Minimally ... RN, Wang A. Percutaneous heart valve replacement for aortic stenosis: state of the evidence. Ann Intern Med . 2010; ...

  17. Bicuspid Aortic Valve

    DTIC Science & Technology

    2006-08-01

    Schnell E, Wollenek G, Maurer G, Baumgartner H, Lang IM. Mechanisms underlying aortic dilatation in congenital aortic valve malformation . Circulation...1999; 99(16):2138-2143. 10. Roberts CS, Roberts WC. Dissection of the aorta associated with congenital malformation of the aortic valve. J Am Coll... congenital heart defect, often diagnosed incidentally or as a consequence of an associated condition. Patients with this anomaly are at increased risk

  18. Development of furnished cages for laying hens.

    PubMed

    Appleby, M C; Walker, A W; Nicol, C J; Lindberg, A C; Freire, R; Hughes, B O; Elson, H A

    2002-09-01

    1. A 3-year trial was carried out of cages for laying hens, occupying a full laying house. The main cage designs used were 5000 cm2 in area, 50 cm high at the rear and furnished with nests and perches. F cages had a front rollaway nest at the side, lined with artificial turf. FD cages also had a dust bath containing sand over the nest. H cages had two nest hollows at the side, one in front of the other. They were compared with conventional cages 2500 cm2 in area and 38 cm high at the rear. 2. Cages were stocked with from 4 to 8 ISA Brown hens per cage, resulting in varied allowances of area, feeder and perch per bird. No birds were beak trimmed. In F and FD cages two further treatments were applied: nests and dust baths were sometimes fitted with gates to exclude birds from dust baths in the morning and from both at night; elevated food troughs, with a lip 33 cm above the cage floor, were compared with standard troughs. 3. Management of the house was generally highly successful, with temperature control achieved by ventilation. Egg production was above breeders' standards and not significantly affected by cage design. More eggs per bird were collected when there were fewer birds per cage but food consumption also then tended to be higher. 4. The number of downgraded eggs was variable, with some tendency for more in furnished cages. Eggs laid in dust baths were often downgraded. Those laid at the back of the cage were frequently dirty because of accumulation of droppings. H nests were unsuccessful, with less than 50% of eggs laid in the nest hollows. However, up to 93% of eggs were laid in front rollaways, and few of these were downgraded. 5. Feather and foot damage were generally less in furnished than in conventional cages, greater where there were more birds per cage. With an elevated food trough there was less feather damage but more overgrowth of claws. In year 2, mortality was greater in cages with more birds. 6. Pre-laying behaviour was mostly settled in

  19. 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.

  20. Phototriggerable 2′,7-Caged Paclitaxel

    PubMed Central

    Gropeanu, Radu A.; Baumann, Hella; Ritz, Sandra; Mailänder, Volker; Surrey, Thomas; del Campo, Aránzazu

    2012-01-01

    Three different variants of photoactivatable caged paclitaxel (PTX) have been synthesized and their bioactivity was characterized in in vitro assays and in living cells. The caged PTXs contain the photoremovable chromophore 4,5-dimethoxy-2-nitrobenzyloxycarbonyl (Nvoc) attached to position C7, C2' and to both of these positions via a carbonate bond. Single caged PTXs remained biologically active even at low dosages. Double caging was necessary in order to fully inhibit its activity and to obtain a phototriggerable PTX that can be applied successfully at commonly used concentrations. Irradiation of solutions containing the double caged PTX allowed dose-dependent delivery of functional PTX. Light-triggered stabilization of microtubule assemblies in vitro and in vivo by controlled light exposure of tubulin solutions or cell cultures containing caged PTX was demonstrated. Short light exposure under a fluorescence microscope allowed controlled delivery of free PTX during imaging. PMID:22970137

  1. Transcatheter aortic valve implantation in aortic coarctation.

    PubMed

    Schramm, René; Kupatt, Christian; Becker, Christoph; Bombien, René; Reichart, Bruno; Sodian, Ralf; Schmitz, Christoph

    2013-06-01

    A 77-year-old male patient was scheduled for transcatheter aortic valve implantation for symptomatic and severe aortic valve stenosis. Severe multidirectional kinking of the aorta based on aortic coarctation did not allow for the transfemoral, but only for the transapical approach. The procedure was complicated because of the technically challenging retrograde passage of the transfemorally inserted pig-tail catheter required for intraoperative angiography of the aortic root. Correct positioning of the pig-tail catheter into the ascending aorta was accomplished by use of a loop snare, which was advanced into the descending aorta via the antegrade route, passing the cardiac apex, the stenotic aortic valve, and the coarctation-associated kinking. The pig-tail catheter tip was manipulated into the loop snare, pulled traverse the coarctation, and released within the proximal ascending aorta. Subsequent procedures were uneventful and followed the standardized protocol. A 29 mm Edwards Lifescience transcatheter Sapien bioprosthesis was successfully implanted. Georg Thieme Verlag KG Stuttgart · New York.

  2. 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.

  3. 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.

  4. Aortic Valve Disease

    MedlinePlus

    ... body Watch the video below as Dr. Robbin Cohen describes aortic stenosis Video of Robbin G. Cohen, MD on Aortic Stenosis Causes and Symptoms Causes ... when having dental work. Reviewed by: Robbin G. Cohen, MD, with assistance from John Hallsten and Travis ...

  5. 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

  6. Bovine aortic arch with supravalvular aortic stenosis.

    PubMed

    Idhrees, Mohammed; Cherian, Vijay Thomas; Menon, Sabarinath; Mathew, Thomas; Dharan, Baiju S; Jayakumar, K

    2016-09-01

    A 5-year-old boy was diagnosed to have supravalvular aortic stenosis (SVAS). On evaluation of CT angiogram, there was associated bovine aortic arch (BAA). Association of BAA with SVAS has not been previously reported in literature, and to best of our knowledge, this is the first case report of SVAS with BAA. Recent studies show BAA as a marker for aortopathy. SVAS is also an arteriopathy. In light of this, SVAS can also possibly be a manifestation of aortopathy associated with BAA.

  7. Asymptomatic Strut Fracture in DeBakey-Surgitool Aortic Valves

    PubMed Central

    Von Der Emde, Jürgen; Eberlein, Ulrich; Breme, Jürgen

    1990-01-01

    From August 1971 through November 1972, we implanted 62 Model 2 DeBakey-Surgitool aortic valve prostheses in 62 patients, 4 of whom later had clinically asymptomatic strut fractures. In 1 case, the patient died suddenly, and autopsy revealed detachment of the ball-cage; in each of the other 3 cases, fractures of 2 struts close to the base of the prosthesis were diagnosed fluoroscopically, and the patients underwent successful reoperation. The interval between implantation and reoperation ranged from 11 months to 16 years, 9 months. In 1 patient, retrospective study of chest radiographs revealed that the fracture had been present for 2½ years. Larger valves (≥ A6) were affected significantly more often than smaller ones. We performed metallurgic analysis of 1 prosthesis: results revealed strut wear from fatigue cracking and secondary abrasion. Strut fracture was also promoted by suspension of the cage at right angles to the prosthetic ring and by use of a pyrolytic carbon ball in a titanium cage (i.e., an occluder harder than its holder). Patients with DeBakey-Surgitool aortic valve prostheses should undergo annual radiologic examinations to enable early detection of strut fractures. Prophylactic valve replacement is not indicated. (Texas Heart Institute Journal 1990;17:223-7) Images PMID:15227175

  8. 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

  9. Aortic root stiffness affects the kinematics of bioprosthetic aortic valves.

    PubMed

    Jahren, Silje Ekroll; Winkler, Bernhard Michael; Heinisch, Paul Philipp; Wirz, Jessica; Carrel, Thierry; Obrist, Dominik

    2017-02-01

    In this study, the influence of aortic root distensibility on the haemodynamic parameters and valve kinematics of a bioprosthetic aortic valve was investigated in a controlled in vitro experiment. An Edwards INTUITY Elite 21 mm sutureless aortic valve (Edwards Lifesciences, Irvine, CA, USA) was inserted in three transparent aortic root phantoms with different wall thicknesses (0.55, 0.85 and 1.50 mm) mimicking different physiological distensibilities. Haemodynamic measurements were performed in an in vitro flow loop at heart rates of 60, 80 and 100 bpm with corresponding cardiac outputs of 3.5, 4.0 and 5.0 l/min and aortic pressures of 100/60, 120/90 and 145/110 mmHg, respectively. Aortic valve kinematics were assessed using a high-speed camera. The geometric orifice area (GOA) was measured by counting pixels in the lumen of the open aortic valve. The effective orifice area (EOA) was calculated from the root-mean-square value of the systolic aortic valve flow rate and the mean systolic trans-valvular pressure gradient. The tested aortic root phantoms reproduce physiological distensibilities of healthy individuals in age groups ranging from 40 to 70 years (±10 years). The haemodynamic results show only minor differences between the aortic root phantoms: the trans-valvular pressure gradient tends to increase for stiffer aortic roots, whereas the systolic aortic valve flow rate remains constant. As a consequence, the EOA decreased slightly for less distensible aortic roots. The GOA and the aortic valve opening and closing velocities increase significantly with reduced distensibility for all haemodynamic measurements. The resulting mean systolic flow velocity in the aortic valve orifice is lower for the stiffer aortic root. Aortic root distensibility may influence GOA and aortic valve kinematics, which affects the mechanical load on the aortic valve cusps. Whether these changes have a significant effect on the onset of structural valve deterioration of bioprosthetic

  10. 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...

  11. 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...

  12. Particle cage dynamics in flowing colloidal dispersions

    NASA Astrophysics Data System (ADS)

    Marenne, Stephanie; Morris, Jeffrey F.

    2016-11-01

    The idea of the particle in a suspension at rest being trapped in a cage formed by its neighbors, widely used to understand glassy suspensions, has been applied to freely flowing suspensions. Stokesian Dynamics, a discrete particle simulation, is used to simulate the flow of monodisperse colloidal hard sphere suspensions. The cage analogy is useful to study the nonlinear stress in the material during start-up of shear flow, where the neighbor cage deforms and breaks, and during oscillatory shear flow where, depending on the amplitude of oscillation, the particle is trapped inside the cage or escapes during the oscillation cycle. A precise statistical definition of the cage in terms of the nearest neighbor ring in the pair distribution function is developed. We examine the dependence of the cage dynamics on the volume fraction of particles and the Peclet number Pe , the ratio between shear and Brownian forces. Under flow, the cage is found to break at quite definite positions, and the structural distortion is found to be clearly related to the shear and normal stress response. The shear strain needed to break the neighbor cage depends on Pe as Brownian motion enhances the total deformation. A simple model captures the strain at the stress overshoot for start-up of steady shear.

  13. Molecular shape sorting using molecular organic cages.

    PubMed

    Mitra, Tamoghna; Jelfs, Kim E; Schmidtmann, Marc; Ahmed, Adham; Chong, Samantha Y; Adams, Dave J; Cooper, Andrew I

    2013-04-01

    The energy-efficient separation of chemical feedstocks is a major sustainability challenge. Porous extended frameworks such as zeolites or metal-organic frameworks are one potential solution to this problem. Here, we show that organic molecules, rather than frameworks, can separate other organic molecules by size and shape. A molecular organic cage is shown to separate a common aromatic feedstock (mesitylene) from its structural isomer (4-ethyltoluene) with an unprecedented perfect specificity for the latter. This specificity stems from the structure of the intrinsically porous cage molecule, which is itself synthesized from a derivative of mesitylene. In other words, crystalline organic molecules are used to separate other organic molecules. The specificity is defined by the cage structure alone, so this solid-state 'shape sorting' is, uniquely, mirrored for cage molecules in solution. The behaviour can be understood from a combination of atomistic simulations for individual cage molecules and solid-state molecular dynamics simulations.

  14. 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.

  15. Excessive strut wear allowing ball-poppet embolization in a DeBakey-Surgitool aortic valve prosthesis.

    PubMed

    Sutherland, R D; Guynes, W A; Nichols, C T; Martinez, H E

    1982-01-01

    Excessive cage strut wear allowing ball-poppet embolization caused the sudden death of a 47 year old lady in whom a DeBakey-Surgitool aortic prosthesis had been implanted nine years earlier. Patients with this type of prosthesis should have periodic valvular cine fluoroscopy with image intensification to allow visualization of significant strut wear or fracture, and appropriate prosthetic valve replacement.

  16. 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

  17. Aortic Valve Stenosis

    MedlinePlus

    ... evaluation of aortic stenosis in adults. http://www.uptodate.com/home. Accessed April 29, 2014. Mohty D, ... Valvular heart disease in elderly adults. http://www.uptodate.com/home. Accessed May 2, 2014. Bonow RO, ...

  18. Aortic Aneurysm Statistics

    MedlinePlus

    ... this? Submit What's this? Submit Button Related CDC Web Sites Heart Disease Stroke High Blood Pressure Salt ... to Prevent and Control Chronic Diseases Million Hearts® Web Sites with More Information About Aortic Aneurysm For ...

  19. Aortic Valve Stenosis

    MedlinePlus

    ... pulmonary valve and aortic valve. Each valve has flaps (cusps or leaflets) that open and close once ... valve consists of three tightly fitting, triangular-shaped flaps of tissue called cusps. Some children are born ...

  20. Mild aerobic exercise blocks elastin fiber fragmentation and aortic dilatation in a mouse model of Marfan syndrome associated aortic aneurysm.

    PubMed

    Gibson, Christine; Nielsen, Cory; Alex, Ramona; Cooper, Kimbal; Farney, Michael; Gaufin, Douglas; Cui, Jason Z; van Breemen, Cornelis; Broderick, Tom L; Vallejo-Elias, Johana; Esfandiarei, Mitra

    2017-07-01

    Regular low-impact physical activity is generally allowed in patients with Marfan syndrome, a connective tissue disorder caused by heterozygous mutations in the fibrillin-1 gene. However, being above average in height encourages young adults with this syndrome to engage in high-intensity contact sports, which unfortunately increases the risk for aortic aneurysm and rupture, the leading cause of death in Marfan syndrome. In this study, we investigated the effects of voluntary (cage-wheel) or forced (treadmill) aerobic exercise at different intensities on aortic function and structure in a mouse model of Marfan syndrome. Four-week-old Marfan and wild-type mice were subjected to voluntary and forced exercise regimens or sedentary lifestyle for 5 mo. Thoracic aortic tissue was isolated and subjected to structural and functional studies. Our data showed that exercise improved aortic wall structure and function in Marfan mice and that the beneficial effect was biphasic, with an optimum at low intensity exercise (55-65% V̇o2max) and tapering off at a higher intensity of exercise (85% V̇o2max). The mechanism underlying the reduced elastin fragmentation in Marfan mice involved reduction of the expression of matrix metalloproteinases 2 and 9 within the aortic wall. These findings present the first evidence of potential beneficial effects of mild exercise on the structural integrity of the aortic wall in Marfan syndrome associated aneurysm. Our finding that moderate, but not strenuous, exercise protects aortic structure and function in a mouse model of Marfan syndrome could have important implications for the medical care of young Marfan patients.NEW & NOTEWORTHY The present study provides conclusive scientific evidence that daily exercise can improve aortic health in a mouse model of Marfan syndrome associated aortic aneurysm, and it establishes the threshold for the exercise intensity beyond which exercise may not be as protective. These findings establish a platform for

  1. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Ziaja, K; Sedlak, L; Urbanek, T; Kostyra, J; Ludyga, T

    2000-01-01

    The reported incidence of inflammatory abdominal aortic aneurysm (IAAA) is from 2% to 14% of patients with abdominal aortic aneurysm and the etiology of this disease is still discussed--according to the literature several pathogenic theories have been proposed. From 1992 to 1997 32 patients with IAAA were operated on. The patients were mostly symptomatic--abdominal pain was present in 68.75% cases, back pain in 31.25%, fever in 12.5% and weight loss in 6.25% of the operated patients. In all the patients ultrasound examination was performed, in 4 patients CT and in 3 cases urography. All the patients were operated on and characteristic signs of inflammatory abdominal aortic aneurysm like: thickened aortic wall, perianeurysmal infiltration or retroperitoneal fibrosis with involvement of retroperitoneal structures were found. In all cases surgery was performed using transperitoneal approach; in three cases intraoperatively contiguous abdominal organs were injured, which was connected with their involvement into periaortic inflammation. In 4 cases clamping of the aorta was done at the level of the diaphragmatic hiatus. 3 patients (9.37%) died (one patient with ruptured abdominal aortic aneurysm). Authors present diagnostic procedures and the differences in the surgical tactic, emphasizing the necessity of the surgical therapy in patients with inflammatory abdominal aortic aneurysm.

  2. Are Aortic Stent Grafts Safe in Pregnancy?

    PubMed Central

    Khandanpour, Nader; Mehta, Tapan A.; Adiseshiah, M.; Meyer, Felicity J.

    2015-01-01

    Aortic stent grafts are increasingly used to treat aortic aneurysms and also other aortic pathologies. The safety of aortic stent grafts in pregnancy has never been studied or reported. We report on two cases of aortic stent grafts in pregnant women and discuss the effect of pregnancy on these aortic stent grafts. PMID:26229702

  3. Clinical and morphologic observations after simultaneous replacement of the tricuspid, mitral and aortic valves.

    PubMed

    Sullivan, M F; Roberts, W C

    1986-10-01

    Clinical and morphologic observations are described in 12 patients who underwent simultaneous replacement of the tricuspid, mitral and aortic valves. All 12 patients had mitral stenosis, 10 aortic valve stenosis and 2 pure aortic valve regurgitation; 5 had tricuspid valve stenosis and 7 pure tricuspid valve regurgitation. Of the 10 patients who died within 60 days of triple valve replacement, 7 had the low cardiac output syndrome, which in 4, and possibly 5, of the 7 was attributed to prosthetic aortic valve stenosis. In none of the 12 patients was the ascending aorta dilated, and in the 4 (possibly 5) patients with low cardiac output, the space between the surface of the caged poppet (4 patients) or margins of the tilting disc (1 patient) in the aortic valve position and the aortic endothelium appeared inadequate to allow unobstructed flow despite small-sized prostheses in all but 1 patient. Thus, aortic valve replacement in the setting of triple valve dysfunction is hazardous or potentially so. The relative small sizes of the hearts in these patients also make valve replacement more difficult (and hazardous) compared to hearts with larger ventricles and aortas.

  4. Aortic involvement in relapsing polychondritis.

    PubMed

    Le Besnerais, Maëlle; Arnaud, Laurent; Boutémy, Jonathan; Bienvenu, Boris; Lévesque, Hervé; Amoura, Zahir; Marie, Isabelle

    2017-05-17

    To assess prevalence of aortic involvement in relapsing polychondritis (RP) patients; to evaluate clinical features and long-term outcome of RP patients exhibiting aortitis, aortic ectasia and/or aneurysm. One hundred and seventy-two RP patients underwent aortic computed tomography (CT)-scan; they were seen in 3 medical centers. Eleven patients (6.4%) had aortic involvement, occurring within a median time of 2 years after RP diagnosis. CT-scan showed isolated aortitis (n=2); the 9 other patients exhibited: aortitis and aortic aneurysm (n=2) or ectasia (n=1), isolated aortic aneurysm (n=4) or ectasia (n=2); aortic localizations were as follows: thoracic (n=6), abdominal (n=2), thoracic and abdominal (n=4) aorta. Patients exhibited: resolution (n=3) improvement (n=3), stabilization (n=4) or deterioration (n=1) of aortic localization. Five patients experienced recurrence of aortic localization; one patient died of aortic abdominal aneurysm rupture. Predictive factors of death related to aortic complications were: aortitis on CT-scan, higher median levels of erythrocyte sedimentation rate. Predictive parameters of aortic relapses were: aortitis on CT-scan and involvement of the abdominal aorta. This study underlines that aortic involvement is severe in RP. Furthermore, we suggest that RP patients exhibiting poor prognostic factors, including panaortitis and higher values of ESR, may require more aggressive therapy. Copyright © 2017 Société française de rhumatologie. Published by Elsevier SAS. All rights reserved.

  5. Successful transfemoral aortic valve implantation through aortic stent graft after endovascular repair of abdominal aortic aneurysm.

    PubMed

    Kawashima, Hideyuki; Watanabe, Yusuke; Kozuma, Ken

    2017-04-01

    The patient was a 91-year-old woman presenting with severe aortic valve stenosis. Pre-procedural computed tomography scan revealed a 45-mm abdominal aortic aneurysm (AAA). Transfemoral transcatheter aortic valve implantation (TF-TAVI) was performed after endovascular aortic repair (EVAR) of the AAA. The 23-mm Edwards Sapien XT system passed through the aortic stent graft smoothly. This is the first case report showing that successful TF-TAVI can be performed through a prior abdominal aortic stent graft. TF-TAVI after EVAR of AAA is a feasible option for patients with extremely poor access.

  6. 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

  7. Cage allocation designs for rodent carcinogenicity experiments

    PubMed Central

    Herzberg, Agnes M.; Lagakos, Stephen W.

    1991-01-01

    Cage allocation designs for rodent carcinogenicity experiments are discussed and presented with the goal of avoiding dosage group biases related to cage location. Considerations in selecting a cage design are first discussed in general terms. Specific designs are presented for use in experiments involving three, four, and five dose groups and with one, four, and five rodents per cage. Priorities for balancing treatment groups include horizontal position on shelf and shelf of rack, nearest neighbor balance, and male–female balance. It is proposed that these balance criteria be considered together with practical issues, such as the ability to accurately conform to a design and to determine a sensible and efficient design for each experiment. PMID:17539183

  8. Cage allocation designs for rodent carcinogenicity experiments.

    PubMed Central

    Herzberg, A M; Lagakos, S W

    1992-01-01

    Cage allocation designs for rodent carcinogenicity experiments are discussed and presented with the goal of avoiding dosage group biases related to cage location. Considerations in selecting a cage design are first discussed in general terms. Specific designs are presented for use in experiments involving three, four, and five dose groups and with one, four, and five rodents per cage. Priorities for balancing treatment groups include horizontal position on shelf and shelf of rack, nearest neighbor balance, and male-female balance. It is proposed that these balance criteria be considered together with practical issues, such as the ability to accurately conform to a design and to determine a sensible and efficient design for each experiment. PMID:1295494

  9. Maintenance of a Drosophila melanogaster Population Cage.

    PubMed

    Caravaca, Juan Manuel; Lei, Elissa P

    2016-03-15

    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.

  10. Aortic aneurysm repair - endovascular- discharge

    MedlinePlus

    ... MRI scan Aortic aneurysm repair - endovascular Aortic angiography Hardening of ... Center-Shreveport, Shreveport, LA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla ...

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. Cage change intervals for opossums (Monodelphis domestica) in individually ventilated cages.

    PubMed

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

    2011-09-01

    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.

  16. NMR Evidence of Cage-to-Cage Diffusion of H2 in H2-Clathrates

    NASA Astrophysics Data System (ADS)

    Senadheera, Lasitha; Conradi, Mark

    2008-03-01

    H2 and heavy-ice at P>1 kbar and T ˜250 K form H2-D2O clathrate; four and one H2 may occupy each large (L) and small (S) cage, respectively. In H2-THF-H2O clathrate, H2 occupies singly and only S cages. Previous electronic-structure calculations estimate the barriers for H2 passage though hexagonal and pentagonal faces of cages as ˜6 and ˜25 kcal/mol, respectively. Our H2 NMR linewidth data reflect random crystal fields from frozen cage-wall D2O orientations. We find dramatic reductions in linewidth starting at 120 K (175 K) for H2-D2O (H2-TDF-D2O) indicating time-averaging of the crystal fields. Assuming Arrhenius behavior, our data imply energies for escape from L (S) cages of about ˜4 (˜6) kcal/mol. For L cages, the agreement with the calculated (cages were treated as rigid) barrier is reasonable. For H2 in S cages, in H2-TDF-D2O, the extreme disagreement with theory points to another mechanism of time-averaging, reorientations of the cage-wall D2O molecules, as suggested by previous work in TDH-H2O clathrate. Our limited NMR spectra at high T ˜145 K in H2-D2O show evidence of distinct resonances from diffusionally mobile and immobile H2 molecules, as expected.

  17. Magnetic Fluid Gyro Bearing and Caging Mechanism.

    DTIC Science & Technology

    In accordance wtih this invention, a gyro is provided which has a bearing means between the rotor and stator provided by magnetic fluid and a caging...means which also includes a magnetic fluid provided between the rotor and caging plate. The gyro of this invention includes a stator with motor...and mounted about the circumference of the rotor with magnetic fluid between the rotor and stator spherical surfaces and being held by the permanent

  18. [Congenital aortic stenosis].

    PubMed

    Yamaguchi, M

    2001-08-01

    Recent advances in and controversies concerning the management of children with congenital valvular aortic stenosis are discussed. In neonates with critical aortic stenosis, improved survival has recently been reported after surgical open valvotomy and balloon valvuloplasty, although it is difficult at this point to compare the results of the two procedures and determine their differential indications. Good results have also been achieved after extended aortic valvuloplasty for recurrent aortic stenosis and/or insufficiency, but the length of follow-up in these patients is still short. The technique first reported in 1991 for bilateral enlargement fo a small annulus permits the insertion of an aortic valve 3-4 sizes larger than the native annulus. It entails no risk of distorting the mitral valve, damaging the conduction system or important branches of the coronary arteries, or resulting in left ventricular dysfunction. The Ross procedure is now widely applied in the West, with reports of early mortality rates of less than 5% and event-free survival rates of 80-90% during follow-up of 4-8 years. Longer follow-up and continued careful evaluation are required to resolve the issue of possible dilatation and subsequent neoaortic valve dysfunction and pulmonary stenosis due to allograft degeneration after pulmonary autograft root replacement in children.

  19. Robotic aortic surgery.

    PubMed

    Duran, Cassidy; Kashef, Elika; El-Sayed, Hosam F; Bismuth, Jean

    2011-01-01

    Surgical robotics was first utilized to facilitate neurosurgical biopsies in 1985, and it has since found application in orthopedics, urology, gynecology, and cardiothoracic, general, and vascular surgery. Surgical assistance systems provide intelligent, versatile tools that augment the physician's ability to treat patients by eliminating hand tremor and enabling dexterous operation inside the patient's body. Surgical robotics systems have enabled surgeons to treat otherwise untreatable conditions while also reducing morbidity and error rates, shortening operative times, reducing radiation exposure, and improving overall workflow. These capabilities have begun to be realized in two important realms of aortic vascular surgery, namely, flexible robotics for exclusion of complex aortic aneurysms using branched endografts, and robot-assisted laparoscopic aortic surgery for occlusive and aneurysmal disease.

  20. Aortic hammer syndrome.

    PubMed

    Komen, Niels; Vercauteren, Sven; de Roover, Dominique

    2011-08-01

    To present a case of penetrating aortic ulcer with extraordinary etiology. A 57-year-old man was admitted with acute retrosternal and interscapular pain. He was a demolition worker and often used a pneumatic drill to which he pressed his chest as he drilled. Clinical examination showed previously undiagnosed hypertension. Computed tomographic angiography disclosed a penetrating aortic ulcer in the descending thoracic aorta without any sign of atherosclerosis. Initial treatment consisted of blood pressure control. However, due to progression of the lesion, endovascular treatment was performed to implant a covered endoprosthesis. We hypothesize that the etiology of the ulcer was the shear forces developed by incorrect, repetitive use of the pneumatic hammer in combination with the untreated hypertension. This is analogous to the hypothenar hammer syndrome, and we propose naming this the "aortic hammer syndrome."

  1. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Mikami, Y; Kyogoku, M

    1994-08-01

    Inflammatory abdominal aortic aneurysm (IAAA) is a distinct clinicopathological entity, characterized by: (1) clinical presentation, such as back pain, weight loss, and increased ESR, (2) patchy and/or diffuse lymphoplasmacytic infiltration, and (3) marked periaortic fibrosis resulting in thickening of the aneurysmal wall and occasional retroperitoneal fibrosis. Its pathogenesis is unknown, but some authors support the theory that IAAA is a subtype of atherosclerotic abdominal aortic aneurysm because of close relationship between IAAA and atherosclerotic change. In this article, we describe clinical and histological features of IAAA on the basis of the literature and our review of 6 cases of IAAA, emphasizing the similarity and difference between IAAA and atherosclerotic abdominal aortic aneurysm. Our review supports that marked lamellar fibrosis completely replacing the media and adventitia, patchy lymphocytic infiltration (mostly B cells) and endarteritis obliterans are characteristic features of IAAA.

  2. Furnished cage system and hen well-being: Comparative effects of furnished cages and battery cages on behavioral exhibitions in White Leghorn chickens.

    PubMed

    Pohle, K; Cheng, H-W

    2009-08-01

    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 hundred ninety-two 1-d-old non-beak-trimmed Hy-Line W-36 White Leghorn chicks were reared using standard management practices in raised wire cages. At 19 wk of age, the birds were randomly assigned into battery cages or furnished cages. The battery cages were commercial wire cages containing 6 birds per cage, providing 645 cm(2) of floor space per birds. The furnished cages had wire floors and solid metal walls, with perches, a dustbathing area, scratch pads, and a nestbox area with a concealment curtain. Based on the company recommendations, 10 birds were housed per cage, providing a stocking density of 610 cm(2) of floor space per bird. Behavioral observations were conducted using the Noldus Observer software package. The birds were observed at 5-min intervals for the entire light period. The birds housed in battery cages had higher posture and behavioral transitions and increased time spent walking and performing exploratory behavior (P < 0.05, 0.01, respectively), which may indicate they were stressed, resulting in restlessness, whereas the birds housed in furnished cages had higher levels of preening (P < 0.05). Preening has been considered as a comfort behavior in birds. These results may suggest that furnished cages may be a favorable alternative system for housing birds by allowing them to perform certain natural behaviors.

  3. Chronic Type A Aortic Dissection and Giant Aortic Root Aneurysm After Aortic Valve Replacement

    PubMed Central

    Puga, Andrés Enríquez; Rodríguez, Sara Castaño; Pañero, Blanca Mateos; Moreira, Beatriz Castaño; López Almodóvar, Luis Fernando

    2016-01-01

    We describe the case of a 61-year-old male with a giant aortic root aneurysm associated with chronic aortic Type A dissection. The patient had been operated on 16 years before due to aortic annuloectasia with mechanical valve replacement. The patient underwent revision aortic surgery with a Bentall-De Bono operation with Svensson modification, using a #21 On-X Valsalva mechanical valve conduit. The postoperative course was uneventful. PMID:28097190

  4. Microclimatic Variation Within Sleeve Cages Used in Ecological Studies

    PubMed Central

    Nelson, Lori A.; Rieske, Lynne K.

    2014-01-01

    Abstract Sleeve cages for enclosing or excluding arthropods are essential components of field studies evaluating trophic interactions. Microclimatic variation in sleeve cages was evaluated to characterize its potential effects on subsequent long-term experiments. Two sleeve cage materials, polyester and nylon, and two cage sizes, 400 and 6000 cm 2 , were tested on eastern hemlock, Tsuga canadensis (L.) Carrière. Temperature and relative humidity inside and outside cages, and the cost and durability of the cage materials, were compared. Long-term effects of the sleeve cages were observed by measuring new growth on T. canadensis branches. The ultimate goal was to identify a material that minimizes bag-induced microclimatic variation. Bagged branches whose microclimates mimic those of surrounding unbagged branches should have minimal effects on plant growth and may prove ideal venues for assessing herbivore and predator behavior under natural conditions. No differences were found in temperature or humidity between caging materials. Small cages had higher average temperatures than large cages, especially in the winter, but this difference was confounded by the fact that small cages were positioned higher in trees than large cages. Differences in plant growth were detected. Eastern hemlock branches enclosed within polyester cages produced fewer new growth tips than uncaged controls. Both polyester and nylon cages reduced the length of new shoot growth relative to uncaged branches. In spite of higher costs, nylon cages were superior to polyester with respect to durability and ease of handling. PMID:25368083

  5. Microclimatic variation within sleeve cages used in ecological studies.

    PubMed

    Nelson, Lori A; Rieske, Lynne K

    2014-01-01

    Sleeve cages for enclosing or excluding arthropods are essential components of field studies evaluating trophic interactions. Microclimatic variation in sleeve cages was evaluated to characterize its potential effects on subsequent long-term experiments. Two sleeve cage materials, polyester and nylon, and two cage sizes, 400 and 6000 cm(2), were tested on eastern hemlock, Tsuga canadensis (L.) Carrière. Temperature and relative humidity inside and outside cages, and the cost and durability of the cage materials, were compared. Long-term effects of the sleeve cages were observed by measuring new growth on T. canadensis branches. The ultimate goal was to identify a material that minimizes bag-induced microclimatic variation. Bagged branches whose microclimates mimic those of surrounding unbagged branches should have minimal effects on plant growth and may prove ideal venues for assessing herbivore and predator behavior under natural conditions. No differences were found in temperature or humidity between caging materials. Small cages had higher average temperatures than large cages, especially in the winter, but this difference was confounded by the fact that small cages were positioned higher in trees than large cages. Differences in plant growth were detected. Eastern hemlock branches enclosed within polyester cages produced fewer new growth tips than uncaged controls. Both polyester and nylon cages reduced the length of new shoot growth relative to uncaged branches. In spite of higher costs, nylon cages were superior to polyester with respect to durability and ease of handling.

  6. Aortic Valve Adaptation to Aortic Root Dilatation

    PubMed Central

    Kim, Dae-Hee; Handschumacher, Mark D.; Levine, Robert A.; Sun, Byung Joo; Jang, Jeong Yoon; Yang, Dong Hyun; Kang, Joon-Won; Song, Jong-Min; Kang, Duk-Hyun; Lim, Tae-Hwan; Song, Jae-Kwan

    2015-01-01

    Background The 3-dimensional relationship between aortic root and cusp is essential to understand the mechanism of aortic regurgitation (AR) because of aortic root dilatation (ARD). We sought to test the hypothesis that the stretched cusps in ARD enlarge to compensate for ARD. Methods and Results Computed tomography imaged 92 patients (57 with ARD, 29 with moderate to severe AR, 28 without significant AR) and 35 normal controls. Specialized 3-dimensional software measured individual cusp surface areas relative to maximal mid-sinus cross-sectional area and minimal 3-dimensional annular area, coaptation area fraction, and asymmetry of sinus volumes and intercommissural distances. Total open cusp surface area increased (P<0.001) from 7.6±1.4 cm2/m2 in normals to 12.9±2.2 cm2/m2 in AR-negative and 15.2±3.3 cm2/m2 in AR-positive patients. However, the ratio of closed cusp surface area to maximal mid-sinus area, reflecting cusp adaptation, decreased from normals to AR-negative to AR-positive patients (1.38±0.20, 1.15±0.15, 0.88±0.15; P<0.001), creating the lowest coaptation area fraction. Cusp distensibility (closed diastolic versus open area) decreased from 20% in controls and AR-negative patients to 5% in AR-positive patients (P<0.001). Multivariate determinants of AR and coaptation area fraction reflected both sinus size and cusp-to-annular adaptation. ARD was also progressively asymmetrical with root size, and individual cusp surface areas failed to match this asymmetry. Conclusions Aortic cusp enlargement occurs in ARD, but cusp adaptation and distensibility become limited in prominent, asymmetrical ARD, leading to AR. Optimal AR repair tailored to individual patient anatomy can benefit from appreciating valve adaptation and 3-dimensional relationships; understanding cusp adaptation mechanisms may ultimately provide therapeutic opportunities to improve such compensation. PMID:25051951

  7. Inflammatory abdominal aortic aneurysm.

    PubMed

    Savarese, R P; Rosenfeld, J C; DeLaurentis, D A

    1986-05-01

    Between January 1976 and December 1982, 181 patients with abdominal aortic aneurysms were treated surgically, and in 13 patients the aneurysms were found to be inflammatory. Inflammatory aneurysms of the abdominal aorta (IAAA) share important characteristics with typical atherosclerotic abdominal aortic aneurysms. Diagnosis and surgical management of IAAA are distinctive which suggests that IAAA should be considered separately, as a varient of typical abdominal aortic aneurysms. IAAA occur predominantly in males. The presenting symptoms are often idiosyncratic and include severe abdominal or back pain, or both, and ureteral obstruction; the diagnosis of IAAA should be considered when these symptoms are present. Although grossly and microscopically, the perianeurysmal fibrosis resembles idiopathic retroperitoneal fibrosis, the two conditions can be differentiated. At the present time, ultrasonography and computed tomography appear to offer reliable means for diagnosing IAAA. The presence of IAAA, whether established preoperatively or discovered unexpectedly at operation, necessitate certain modifications in the surgical approach, in order to avoid injuring the duodenum and the venous structures. Most patients can be successfully treated by resection and graft replacement. Rupture of the aneurysm in IAAA appears to be less frequent than in typical atherosclerotic abdominal aortic aneurysm.

  8. Development of net cage acoustic alarm system

    NASA Astrophysics Data System (ADS)

    Hong, Shih-Wei; Wei, Ruey-Chang

    2001-05-01

    In recent years, the fishery production has been drastically decreased in Taiwan, mainly due to overfishing and coast pollution; therefore, fishermen and corporations are encouraged by government to invest in ocean net cage aquaculture. However, the high-price fishes in the net cage are often coveted, so incidences of fish stealing and net cage breaking were found occasionally, which cause great economical loss. Security guards or a visual monitoring system has limited effect, especially in the night when these intrusions occur. This study is based on acoustic measure to build a net cage alarm system, which includes the sonobuoy and monitor station on land. The sonobuoy is a passive sonar that collects the sounds near the net cage and transmits the suspected signal to the monitor station. The signals are analyzed by the control program on the personal computer in the monitor station, and the alarms at different stages could be activated by the sound levels and durations of the analyzed data. To insure long hours of surveillance, a solar panel is applied to charge the battery, and a photodetector is used to activate the system.

  9. Efficacy of Stentless Aortic Bioprosthesis Implantation for Aortic Stenosis with Small Aortic Annulus.

    PubMed

    Murashita, Takashi; Okada, Yukikatsu; Kanemitsu, Hideo; Fukunaga, Naoto; Konishi, Yasunobu; Nakamura, Ken; Koyama, Tadaaki

    2015-09-01

    In patients with small aortic annulus, sufficient size of stented aortic bioprosthesis cannot be implanted without additional procedures. In such cases, we use stentless aortic bioprosthesis to obtain sufficient effective orifice area. In this study, we investigated long-term impact of stentless aortic bioprosthesis on clinical outcomes, compared with stented aortic bioprosthesis. We retrospectively investigated 140 patients who underwent aortic valve replacement (AVR) with porcine bioprosthesis for severe aortic stenosis between 1999 and 2010. Patients who had moderate or more aortic regurgitation and who underwent concomitant mitral procedures were excluded. A total of 69 patients (49%) were implanted stentless bioprosthesis (Freestyle group; Medtronic Inc, Minneapolis, Minnesota, United States) and 71 patients (51%) were implanted stented bioprosthesis (Mosaic group; Medtronic Inc). Follow-up was complete in 97.9% patients. Median follow-up period was 4.2 years. Patients in Freestyle group had smaller body surface area, smaller aortic annulus diameter, smaller aortic valve area, larger mean pressure gradient, higher peak velocity across aortic valve, larger left ventricular mass index (LVMI), and lower left ventricular ejection fraction (LVEF). Mean size of implanted prosthesis was larger in Freestyle group. In-hospital mortality was 1.4% in Freestyle group and 2.8% in Mosaic group (p = 0.980). Five-year survival rate was not different between two groups (5-year survival rate was 87.5 ± 4.7% in Freestyle group and 84.1 ± 7.5% in Mosaic group; log rank, p = 0.619). Late New York Heart Association functional class was lower in Freestyle group. Late LVMI and LVEF became similar between two groups. Stentless aortic bioprosthesis is superior in left ventricular remodeling after AVR for aortic stenosis and is especially effective for small aortic annulus. Georg Thieme Verlag KG Stuttgart · New York.

  10. 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.

  11. 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

  12. The effect of the water/methane interface on methane hydrate cages: the potential of mean force and cage lifetimes.

    PubMed

    Mastny, Ethan A; Miller, Clark A; de Pablo, Juan J

    2008-07-21

    Molecular dynamics simulations were used to determine the influence of a methane-water interface on the position and stability of methane hydrate cages. A potential of mean force was calculated as a function of the separation of a methane hydrate cage and a methane-water interface. The hydrate cages are found to be strongly repelled from the methane gas into the water phase. At low enough temperatures, however, the most favorable location for the hydrate cage is at the interface on the water side. Cage lifetime simulations were performed in bulk water and near a methane-water interface. The methane-water interface increases the cage lifetime by almost a factor of 2 compared to cage lifetimes of cages in bulk water. The potential of mean force and the cage lifetime results give additional explanations for the proposed nucleation of gas hydrates at gas-water interfaces.

  13. Rib cage mechanics after median sternotomy.

    PubMed Central

    Locke, T J; Griffiths, T L; Mould, H; Gibson, G J

    1990-01-01

    A substantial reduction in lung volumes occurs after sternotomy, but the mechanism or mechanisms are unclear. Measurements were made of lung volumes and of chest wall motion with four pairs of magnetometers (two pairs for anteroposterior rib cage, one for lateral rib cage, and one for anteroposterior abdominal dimensions) in 16 men before and one week and three months after coronary artery grafting. Reductions in all lung volumes occurred after sternotomy and were greater in the supine than in the sitting position. Supine vital capacity was reduced one week after surgery, with almost complete recovery at three months. One week after sternotomy there was a significant reduction in tidal volume from a mean (95% confidence limits) value of 0.88 (0.76-1.00) litre to 0.61 (0.52-0.70) l, and in supine rib cage displacement from 3.87 (1.96-5.78) mm to 0.44 (-0.61-1.49) mm in the lateral plane. Respiratory frequency increased from 16 (13-19) to 21 (19-24)/min. Coordination of the rib cage was assessed by measuring the difference in timing of onset of chest wall motion and airflow in four planes. At one week nine of 14 patients showed uncoordination between airflow and rib cage motion in one or more dimensions, and this was still present in three patients at three months. No loss of the temporal relation between airflow and abdominal wall motion was detected. The results suggest that reduced and uncoordinated rib cage expansion contributes to the restrictive ventilatory defect that follows median sternotomy. PMID:2392792

  14. Cage subsidence after anterior cervical discectomy and fusion using a cage alone or combined with anterior plate fixation.

    PubMed

    Pinder, E M; Sharp, D J

    2016-04-01

    To compare the extent of cage subsidence after anterior cervical discectomy and fusion (ACDF) using a cage alone or combined with anterior plate fixation, and to assess the effect of end plate removal on cage subsidence. Records of 23 men and 13 women aged 32 to 82 (mean, 54) years who underwent ACDF for 61 levels using the Solis cage alone (n=46) or combined with anterior plate fixation (n=15) were reviewed. The extent of cage subsidence was determined by comparing immediately postoperative (within one week) with final follow-up radiographs. Cage subsidence was defined as the sum subsidence of the superior and inferior part of the cage into the vertebral body. Mild and major cage subsidence was defined as ≤2 mm and >2 mm, respectively. Patients who underwent ACDF using a cage alone or combined with anterior plate fixation were comparable in terms of age, gender, follow-up duration, and number of levels decompressed. Cage subsidence occurred in 33 (54%) of the 61 levels decompressed. In the cage alone group, the extent of cage subsidence was greater (1.68 vs. 0.57 mm, p=0.039) and the rate of major cage subsidence was higher (28% vs. 7%, p=0.08). The inferior part of the cage was more vulnerable to subsidence compared with the superior part (median subsidence: 3.0 vs. 1.4 mm, p<0.0001). Cage subsidence occurred more often when the end plate was removed rather than preserved (58% vs. 18%, p<0.002). The extent of cage subsidence was greater after ACDF with cage alone. Cage subsidence occurred more often when the end plate was removed. Additional anterior plate fixation is recommended when the end plate is removed.

  15. Aortic coarctation with persistent fifth left aortic arch.

    PubMed

    Santoro, Giuseppe; Caianiello, Giuseppe; Palladino, Maria Teresa; Iacono, Carola; Russo, Maria Giovanna; Calabrò, Raffaele

    2009-08-14

    A neonate with severe aortic coarctation showed a double lumen transverse aorta (persistent fifth aortic arch) with both channels joining at the isthmus where the obstruction was confirmed by echocardiography and cardiac catheterization. Surgical repair was performed with a pantaloon-shaped patch. Persistent fifth aortic arch does not result in a vascular ring and, per se, is not hemodynamically significant unless associated with other cardiac malformations.

  16. Aortic compressor for aortic occlusion in hemorrhagic shock.

    PubMed

    Mahoney, B D; Gerdes, D; Roller, B; Ruiz, E

    1984-01-01

    The aortic compressor is a device that allows rapid, simple, immediately reversible occlusion of the thoracic aorta, without the aortic dissection required to use an aortic cross-clamp. We evaluated the aortic compressor in a controlled study using a canine hemorrhagic shock model. Twelve mongrel dogs were exsanguinated to a mean arterial pressure (MAP) of 47 mm Hg and maintained at that level for 20 minutes. At that point, all animals had a left lateral thoracotomy. Six study animals had the thoracic aorta occluded at the diaphragm using the compressor. Five minutes after thoracotomy, with or without occlusion, the shed blood was reinfused. Application of the aortic compressor was the only variable. Use of the aortic compressor led to an immediate and statistically significant doubling of the study animals' MAP. The increased afterload of aortic occlusion did not impair cardiac output. The cardiac index of the study animals rose slightly, while that of the control animals fell. At the same time the compressor prevented blood flow to the abdominal aorta. If the canine model can be extrapolated to human application, then the aortic compressor would be expected to enhance perfusion of the heart and brain during hemorrhagic shock, prevent further arterial blood loss from intra-abdominal injury or ruptured abdominal aortic aneurysm, and preserve already diminished cardiac output. Because the aorta does not need to be dissected out to use the compressor, there is no risk of injury to nearby vascular structures.

  17. Genetics Home Reference: supravalvular aortic stenosis

    MedlinePlus

    ... Genetics Home Health Conditions supravalvular aortic stenosis supravalvular aortic stenosis Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Supravalvular aortic stenosis (SVAS) is a heart defect that develops before ...

  18. [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.

  19. 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.

  20. Ruptured abdominal aortic aneurysm.

    PubMed

    Sachs, T; Schermerhorn, M

    2010-06-01

    Ruptured abdominal aortic aneurysm (AAA) continues to be one of the most lethal vascular pathologies we encounter. Its management demands prompt and efficient evaluation and repair. Open repair has traditionally been the mainstay of treatment. However, the introduction of endovascular techniques has altered the treatment algorithm for ruptured AAA in most major medical centers. We present recent literature and techniques for ruptured AAA and its surgical management.

  1. Cage-Busting Leadership. Educational Innovations Series

    ERIC Educational Resources Information Center

    Hess, Frederick M.

    2013-01-01

    A practical and entertaining volume, "Cage-Busting Leadership" will be of profound interest and value to school and district leaders--and to everyone with a stake in school improvement. Rick Hess aptly describes his aims at the start of this provocative book: "I believe that two things are true. It is true, as would-be reformers…

  2. 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)

  3. Cage-Busting Leadership. Educational Innovations Series

    ERIC Educational Resources Information Center

    Hess, Frederick M.

    2013-01-01

    A practical and entertaining volume, "Cage-Busting Leadership" will be of profound interest and value to school and district leaders--and to everyone with a stake in school improvement. Rick Hess aptly describes his aims at the start of this provocative book: "I believe that two things are true. It is true, as would-be reformers…

  4. 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…

  5. 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)

  6. 50 CFR 648.75 - Cage identification.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 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) Tagging... from the Regional Administrator. (g) Transfer. See § 648.70(b)(2). (h) Presumptions. Surf clams and...

  7. 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…

  8. 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.

  9. North American single-center experience with a sutureless aortic bioprosthesis.

    PubMed

    de Varennes, Benoit; Lachapelle, Kevin; Cecere, Renzo; Szczepkowski, Isabel; Buithieu, Jean

    2016-03-01

    Surgical sutureless aortic valves have the potential for shorter procedural times and could benefit patients with increased risk. The Enable (Medtronic Inc, Minneapolis, Minn) valve is a bioprosthesis housed in a Nitinol cage allowing folding and deployment once implanted. We aimed to evaluate the early clinical and echocardiographic results with the Enable valve. Patients with aortic stenosis, Society of Thoracic Surgeons score greater than 5.0%, the need for combined procedures, and frailty were considered for Enable implantation. Between August 2012 and October 2014, 63 patients underwent implantation of the Enable valve (Medtronic Inc, Minneapolis, Minn). Thirty patients underwent isolated aortic valve replacement. Combined procedures were aortic valve replacement/coronary artery bypass grafting (26), aortic valve replacement/mitral valve repair (2), aortic valve replacement/mitral valve repair/coronary artery bypass grafting (2), and aortic valve replacement/ascending aortic graft (3). Predicted Society of Thoracic Surgeons score was 8.06 ± 7.73 (0.94-41.30). Implant success was 100%. Mean crossclamp time for isolated aortic valve replacement was 44 ± 14 minutes (30-91). Thirty-day mortality was 1.6% (1/63), and late mortality was 3.2% (2/62). No mortality was valve related. Intraoperative need for revision was 6.3% (4/63). Early migration requiring reoperation occurred in 1.6% of patients (1/63). Postoperative indexed aortic valve area was 1.08 ± 0.22 cm(2)/m(2), and peak and mean gradients were 17 ± 7 mm Hg and 9 ± 4 mm Hg, respectively. The rate of complications was as follows: pacemaker 3.1% (2/63), transient ischemic attack 1.6% (1/63), other thromboembolic events 0%, bleeding 0%, and endocarditis 0%. Mean follow-up was 10 ± 8 months. At latest follow-up, 61 patients were in New York Heart Association class I. Moderate or severe aortic regurgitation did not develop in any patients in the follow-up period. The Enable bioprosthesis is an acceptable

  10. 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

    2016-04-06

    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.

  11. Rib cage mobility in pectus excavatum.

    PubMed

    Mead, J; Sly, P; Le Souef, P; Hibbert, M; Phelan, P

    1985-12-01

    Pectus excavatum is generally regarded as a cosmetic deformity; however, some children with pectus excavatum complain of chest pain and exercise limitation. Physiologic studies sometimes show mild restrictive changes and suggest an increased oxygen cost of breathing. Limitation of rib cage mobility related to the deformity may explain these findings. If rib cage mobility is limited, the ability of the actively inspiring rib cage to lower abdominal pressure would be decreased. If this were so, increased swings in abdominal pressure would be seen during the respiratory cycle, especially at times of stress such as during exercise. To test the hypothesis that pectus excavatum is associated with decreased rib cage mobility, we studied 11 patients with pectus excavatum and 11 control subjects. Four control subjects were also studied with rib cage mobility restricted by chest wall strapping sufficient to decrease vital capacity by 5, 10, and 40%. Gastric pressure was measured using balloon catheters and was used as an index of abdominal pressure. Flow at the mouth was recorded and integrated to give volume. Measurements were made at rest, immediately after exercise, and during graded voluntary inspiration to total lung capacity. Gastric pressure was related to tidal volume, and pressure-volume loops were constructed. There were no differences in abdominal pressure swings during respiration between the patients with pectus excavatum and the control subjects. Both groups showed moderate increase in gastric pressure during inspiration at rest and smaller increases or even decreases in abdominal pressure at end inspiration after exercise and at total lung capacity.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Energy landscapes for diffusion: analysis of cage-breaking processes.

    PubMed

    de Souza, Vanessa K; Wales, David J

    2008-10-28

    A wide spectrum of potential energy barriers exists for binary Lennard-Jones systems. Here we examine the barriers and cage-breaking rearrangements that are pertinent to long-term diffusion. Single-step cage-breaking processes, which follow high-barrier routes, are identified, and different methods and criteria for defining a cage-breaking process are considered. We examine the extent to which a description of cage-breaking within the energy landscape is a description of long-term diffusion. This description includes the identification of cage-breaks that are reversed, and those that are productive towards long-term diffusion. At low temperatures, diffusion is adequately described by productive cage-breaks, or by considering all cage-breaks and accounting for the effect of reversals. To estimate the diffusion constant we require only the mean square displacement of a cage-break, the average waiting time for a cage-break, and a measure of the number of reversed cage-breaks. Cage-breaks can be visualized within the potential energy landscape using disconnectivity graphs, and we compare the use of productive cage-breaks with previous definitions of "megabasins" or "metabasins."

  13. 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 56.19070 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Hoisting Procedures § 56.19070 Closing cage doors or gates. Cage doors or gates shall be closed...

  14. 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 57.19070 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Hoisting Procedures § 57.19070 Closing cage doors or gates. Cage doors or gates shall be closed...

  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 56.19070 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Hoisting Procedures § 56.19070 Closing cage doors or gates. Cage doors or gates shall be closed...

  16. 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 57.19070 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Hoisting Procedures § 57.19070 Closing cage doors or gates. Cage doors or gates shall be closed...

  17. Bacterial eggshell contamination in conventional cages, furnished cages and aviary housing systems for laying hens.

    PubMed

    De Reu, K; Grijspeerdt, K; Heyndrickx, M; Zoons, J; De Baere, K; Uyttendaele, M; Debevere, J; Herman, L

    2005-04-01

    The influence of housing system on the initial bacterial contamination of the eggshell was studied. Two long-term experiments were performed. Bacterial eggshell contamination, as expressed by total count of aerobic and Gram-negative bacteria, was periodically analysed for eggs from a conventional cage, a furnished cage with nest boxes containing artificial turf or grids as nest-floor material and an aviary housing system. Results were log-transformed prior to statistical analyses. For both experiments no systematic differences were found between the conventional cage and furnished cage. The type of nest-floor material in the nest boxes of the furnished cages also did not systematically influence the bacterial contamination. A possible seasonal influence on contamination with a decrease in the winter period (up to > 0.5 log cfu/eggshell) of total count of aerobic and Gram-negative bacteria was observed in the first experiment. The contamination with total aerobic flora was higher (more than 1.0 log) on eggs from the aviary housing system compared to the conventional and the furnished cage systems. For Gram-negative bacteria this was not the case. During the entire period of both experiments, independent of housing system, shell contamination was not influenced by age of hens or period since placing the birds in the houses. For the total count of aerobic bacteria a restricted positive correlation (r2 = 0.66) was found between the concentration of total bacteria in the air of the poultry houses and initial shell contamination.

  18. 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.

  19. Spectrum of aortic valve abnormalities associated with aortic dilation across age groups in Turner syndrome.

    PubMed

    Olivieri, Laura J; Baba, Ridhwan Y; Arai, Andrew E; Bandettini, W Patricia; Rosing, Douglas R; Bakalov, Vladimir; Sachdev, Vandana; Bondy, Carolyn A

    2013-11-01

    Congenital aortic valve fusion is associated with aortic dilation, aneurysm, and rupture in girls and women with Turner syndrome. Our objective was to characterize aortic valve structure in subjects with Turner syndrome and to determine the prevalence of aortic dilation and valve dysfunction associated with different types of aortic valves. The aortic valve and thoracic aorta were characterized by cardiovascular MRI in 208 subjects with Turner syndrome in an institutional review board-approved natural history study. Echocardiography was used to measure peak velocities across the aortic valve and the degree of aortic regurgitation. Four distinct valve morphologies were identified: tricuspid aortic valve, 64% (n=133); partially fused aortic valve, 12% (n=25); bicuspid aortic valve, 23% (n=47); and unicuspid aortic valve, 1% (n=3). Age and body surface area were similar in the 4 valve morphology groups. There was a significant trend, independent of age, toward larger body surface area-indexed ascending aortic diameters with increasing valve fusion. Ascending aortic diameters were (mean±SD) 16.9±3.3, 18.3±3.3, and 19.8±3.9 mm/m(2) (P<0.0001) for tricuspid aortic valve, partially fused aortic valve, and bicuspid aortic valve+unicuspid aortic valve, respectively. Partially fused aortic valve, bicuspid aortic valve, and unicuspid aortic valve were significantly associated with mild aortic regurgitation and elevated peak velocities across the aortic valve. Aortic valve abnormalities in Turner syndrome occur with a spectrum of severity and are associated with aortic root dilation across age groups. Partial fusion of the aortic valve, traditionally regarded as an acquired valve problem, had an equal age distribution and was associated with an increased ascending aortic diameters.

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

    PubMed

    Gu, Yu-Tong; Jia, Lian-Shun; Chen, Tong-Yi

    2007-02-01

    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.

  1. 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

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

    PubMed

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

    2014-09-01

    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. 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. 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. 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.

  3. Porous Organic Cages for Sulfur Hexafluoride Separation

    PubMed Central

    2016-01-01

    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

  4. 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

  5. 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.

  6. A Visible-Light-Sensitive Caged Serotonin.

    PubMed

    Cabrera, Ricardo; Filevich, Oscar; García-Acosta, Beatriz; Athilingam, Jegath; Bender, Kevin J; Poskanzer, Kira E; Etchenique, Roberto

    2017-05-17

    Serotonin, or 5-hydroxytryptamine (5HT), is an important neurotransmitter in the nervous system of both vertebrates and invertebrates. Deficits in 5HT signaling are responsible for many disabling psychiatric conditions, and its molecular machinery is the target of many pharmaceuticals. We present a new 5HT phototrigger, the compound [Ru(bpy)2(PMe3)(5HT)](2+), where PMe3 is trimethylphosphine. As with other ruthenium-bipyridyl based caged compounds, [Ru(bpy)2(PMe3)(5HT)](2+) presents activity in the visible region of the spectrum. We characterize and discuss the photochemical properties of the caged compound, and demonstrate its use by modulating the excitability of mouse prefrontal principal neurons.

  7. [Aortic valve replacement for the small aortic annulus].

    PubMed

    Oshima, H; Usui, A; Akita, T; Ueda, Y

    2006-04-01

    Aortic valve surgery for the small aortic annulus is still challenging for surgeons. Recently, the new types of high performance prosthesis have been developed and the chance of an aortic root enlargement (ARE) is decreasing. In this study, we propose the ideal strategy of the aortic surgery for the small aortic annulus. We analyzed the clinical records of 158 patients who underwent aortic valve replacement from August 1999 to October 2005 in our institution. The small aortic annulus was observed in 38 patients (24%). Fourteen patients of this group underwent ARE. Patient-prosthesis mismatch (PPM) was less frequently observed in patients with ARE compared to those without ARE. The additional time required for ARE was not considerable, and neither ischemic time nor cardiopulmonary bypass time was significantly prolonged by ARE. In conclusion, we have to select a prosthesis with sufficient orifice area to avoid PPM, otherwise we should choose an option of ARE. For this consideration, we definitely need the chart that demonstrates the relationship between the nominal size of various types of prostheses and the size of a patient's annulus that those prostheses actually fit.

  8. Pentacuspid aortic valve diagnosed by transoesophageal echocardiography

    PubMed Central

    Cemri, M; Cengel, A; Timurkaynak, T

    2000-01-01

    Congenital aortic valve anomalies are quite a rare finding in echocardiographic examinations. A case of a 19 year old man with a pentacuspid aortic valve without aortic stenosis and regurgitation, detected by transoesophageal echocardiography, is presented.


Keywords: pentacuspid aortic valve; echocardiography PMID:10995427

  9. Balloon aortic valvuloplasty as a bridge to aortic valve replacement in a patient with severe calcific aortic stenosis.

    PubMed

    Swinkels, B M; Jaarsma, W; Wely, L Relik-van; van Swieten, H A; Ernst, J M P G; Plokker, H W M

    2003-03-01

    This case report describes a patient with severe calcific aortic stenosis who was initially considered inoperable because of a very poor left ventricular function and severe pulmonary hypertension. After balloon aortic valvuloplasty, the clinical and haemodynamic status of the patient improved to such an extent that subsequent aortic valve replacement was considered possible and eventually proved to be successful. Balloon aortic valvuloplasty has value as a potential bridge to aortic valve replacement when the risks for surgery are considered to be too high.

  10. The Beta Cage: Screening Low Radioactive Backgrounds

    NASA Astrophysics Data System (ADS)

    Poinar, K.; Akerib, D.; Grant, D.; Schnee, R.; Shutt, T.; Golwala, S.; Ahmed, Z.

    2006-10-01

    The beta cage is a proposed multi-wire proportional chamber that will be the most sensitive device available to screen low-energy (200 keV) betas emitted at rates as low as 10-5 counts keV^1 cm-2 day-1 (of order 10-4 Bq/m^2). The expected sensitivity and details of the construction and commissioning of its prototype chamber are presented. The prototype beta cage is a 50x50x25 cm frame gridded by stacked wire planes contained in a chamber of gas. To reduce background, the chamber contains only enough mass to stop betas of interest. Samples are placed beneath the grid; the wires multiply the betas and collect their electron avalanche. Readouts allow discrimination of its events from background and determination of the beta (or alpha) source. The beta cage has potential use in carbon or tritium dating, with ^3H/^1H sensitivity of 10-20 and ^ 14C/ ^12C sensitivity of 10-18. Its design was motivated by CDMS, whose sensitivity to the dark matter candidate WIMPs is currently limited by low-energy beta contamination.

  11. Caged Naloxone Reveals Opioid Signaling Deactivation Kinetics

    PubMed Central

    Banghart, Matthew R.; Shah, Ruchir C.; Lavis, Luke D.

    2013-01-01

    The spatiotemporal dynamics of opioid signaling in the brain remain poorly defined. Photoactivatable opioid ligands provide a means to quantitatively measure these dynamics and their underlying mechanisms in brain tissue. Although activation kinetics can be assessed using caged agonists, deactivation kinetics are obscured by slow clearance of agonist in tissue. To reveal deactivation kinetics of opioid signaling we developed a caged competitive antagonist that can be quickly photoreleased in sufficient concentrations to render agonist dissociation effectively irreversible. Carboxynitroveratryl-naloxone (CNV-NLX), a caged analog of the competitive opioid antagonist NLX, was readily synthesized from commercially available NLX in good yield and found to be devoid of antagonist activity at heterologously expressed opioid receptors. Photolysis in slices of rat locus coeruleus produced a rapid inhibition of the ionic currents evoked by multiple agonists of the μ-opioid receptor (MOR), but not of α-adrenergic receptors, which activate the same pool of ion channels. Using the high-affinity peptide agonist dermorphin, we established conditions under which light-driven deactivation rates are independent of agonist concentration and thus intrinsic to the agonist-receptor complex. Under these conditions, some MOR agonists yielded deactivation rates that are limited by G protein signaling, whereas others appeared limited by agonist dissociation. Therefore, the choice of agonist determines which feature of receptor signaling is unmasked by CNV-NLX photolysis. PMID:23960100

  12. 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

  13. Thoracic endovascular aortic repair for blunt thoracic aortic injuries in complex aortic arch vessels anatomies.

    PubMed

    Piffaretti, Gabriele; Carrafiello, Gianpaolo; Ierardi, Anna Maria; Mariscalco, Giovanni; Macchi, Edoardo; Castelli, Patrizio; Tozzi, Matteo; Franchin, Marco

    2015-08-01

    The aim of this study is to report the use of thoracic endovascular aortic repair (TEVAR) in blunt thoracic aortic injuries (BTAIs) presenting with complex anatomies of the aortic arch vessels. Two patients were admitted to our hospital for the management of BTAI. Anomalies were as follow: aberrant right subclavian artery (n = 1) and right-sided aortic arch with 5 vessels anatomy variant (n = 1). TEVAR was accomplished using parallel graft with periscope configuration in the patient with the aberrant right subclavian artery. At 12-month follow-up, computed tomography angiographies confirmed the exclusion of the BTAI, the stability of the endograft, the resolution of the pseudoaneurysm, and the patency of the parallel endograft. Aortic arch vessels variants and anomalies are not rare, and should be recognized and studied precisely to plan the most appropriate operative treatment. TEVAR proved to be effective even in complex anatomies. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Prosthesis-preserving aortic root repair after aortic valve replacement.

    PubMed

    Hamamoto, Masaki; Kobayashi, Taira; Kodama, Hiroshi

    2015-07-01

    We describe a new technique of prosthesis-preserving aortic root replacement for patients who have previously undergone aortic valve replacement. With preservation of the mechanical prosthesis, we implant a Gelweave Valsalva graft using double suture lines. The first suture line is made between the sewing cuff of the mechanical valve and the graft, with mattress sutures of 2/0 braided polyester with pledgets. After the first sutures are tied, the second suture line is created between the graft collar and the aortic root remnant with continuous 4/0 polypropylene sutures.

  15. The excluder aortic endograft.

    PubMed

    Alterman, Daniel M; Stevens, Scott L

    2008-06-01

    Since its introduction, more than 59000 patients have been treated with Gore Excluder endoprosthesis (GORE) for abdominal aortic aneurysm (AAA) in the past 11 years. It has become clearer that differences in device delivery and design provide certain advantages that may favor one anatomical milieu over another. Behavior of the aneurysm sac also seems to be graft dependent as more long-term data become available. The currently available low-permeability GORE seems to have addressed the problem of endotension noted with previous designs. Cumulative data are reviewed, and the data demonstrate very low perioperative morbidity and mortality and excellent protection from aneurysm-related complications with the GORE device. Superior ease of use, excellent trackability, and rare failures requiring acute open conversion characterize the GORE device. By addressing clinical demands of aortic endografting, Gore has eclipsed other endografts in the industry to now dominate the US market. The aim of this review is to describe the history, experience, advantages, and future goals with the GORE for the treatment of AAA.

  16. [Inflammatory abdominal aortic aneurysm].

    PubMed

    Siebenmann, R; Schneider, K; von Segesser, L; Turina, M

    1988-06-11

    348 cases of abdominal aortic aneurysm were reviewed for typical features of inflammatory aneurysm (IAAA) (marked thickening of aneurysm wall, retroperitoneal fibrosis and rigid adherence of adjacent structures). IAAA was present in 15 cases (14 male, 1 female). When compared with patients who had ordinary aneurysms, significantly more patients complained of back or abdominal pain (p less than 0.01). Erythrocyte sedimentation rate was highly elevated. Diagnosis was established in 7 of 10 computed tomographies. 2 patients underwent emergency repair for ruptured aneurysm. Unilateral ureteral obstruction was present in 4 cases and bilateral in 1. Repair of IAAA was performed by a modified technique. Histological examination revealed thickening of the aortic wall, mainly of the adventitial layer, infiltrated by plasma cells and lymphocytes. One 71-year-old patient operated on for rupture of IAAA died early, and another 78-year-old patient after 5 1/2 months. Control computed tomographies revealed spontaneous regression of inflammatory infiltration after repair. Equally, hydronephrosis due to ureteral obstruction could be shown to disappear or at least to decrease. IAAA can be diagnosed by computed tomography with high sensitivity. Repair involves low risk, but modification of technique is necessary. The etiology of IAAA remains unclear.

  17. An Important but Forgotten Technique: Aortic Fenestration.

    PubMed

    Yalcin, Mihriban; Tayfur, Kaptan Derya; Urkmez, Melih

    2016-10-01

    Aortic fenestration is a technique that treats organ ischemia in descending aortic dissection. Open surgical aortic fenestration is an effective yet uncommonly used and widely forgotten procedure. Here, we describe 2 patients suffering from chronic thoracoabdominal aortic dissection, and we aimed to identify under what circumstances surgical aortic fenestration should be applied, to assess its safety and efficacy. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. 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

  19. 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.

  20. Abdominal aortic aneurysm repair - open

    MedlinePlus

    AAA - open; Repair - aortic aneurysm - open ... Open surgery to repair an AAA is sometimes done as an emergency procedure when there is bleeding inside your body from the aneurysm. You may have an ...

  1. Screening for Abdominal Aortic Aneurysm

    MedlinePlus

    ... signs or symptoms of an abdominal aortic aneurysm (AAA). The final recommendation statement summarizes what the Task ... the potential benefits and harms of screening for AAA: (1) Men ages 65 to 75 who smoke ...

  2. Multi-responsive metal-organic lantern cages in solution.

    PubMed

    Brega, Valentina; Zeller, Matthias; He, Yufan; Lu, H Peter; Klosterman, Jeremy K

    2015-03-25

    Soluble copper-based M4L4 lantern-type metal-organic cages bearing internal amines were synthesized. The solution state integrity of the paramagnetic metal-organic cages was demonstrated using NMR, DLS, MS, and AFM spectroscopy. 1D supramolecular pillars of pre-formed cages or covalent host-guest complexes selectively formed upon treatment with 4,4'-bipyridine and acetic anhydride, respectively.

  3. 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.

  4. 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.

  5. Skeletal rearrangements of cage compounds with medium rings

    NASA Astrophysics Data System (ADS)

    Lerman, Berta M.

    1991-04-01

    Data on skeletal rearrangements in the chemistry of cage compounds are reviewed. The main principles of thermodynamically controlled isomerisation of cage hydrocarbons and syntheses of mono- and polycage structures are considered. Data on skeletal reconstruction accompanying functionally substituted carbo- and thia-containing cage-type polycyclanes are systematised. The rules for skeletal interconversions of isomeric tricyclic structures are considered. The bibliography contains 99 references.

  6. Misconceptions and Facts About Aortic Stenosis.

    PubMed

    Argulian, Edgar; Windecker, Stephan; Messerli, Franz H

    2017-04-01

    Aortic stenosis is the most common valvular heart disease leading to intervention, and it is typically a disease of the elderly. Recent clinical advances have expanded the role of transcatheter aortic valve intervention in patients with severe aortic stenosis, making aortic valve intervention feasible and effective even in patients at intermediate, high, and prohibitive surgical risk. With the rapid advances in treatment, proper diagnosis becomes crucial for a wide range of patients with aortic stenosis: from "concordant" high-gradient aortic stenosis to "discordant" low-gradient aortic stenosis. The latter group commonly presents a clinical challenge requiring thoughtful and comprehensive evaluation to determine eligibility for aortic valve intervention. Providers at all levels should be familiar with basic diagnostic caveats and misconceptions when evaluating patients with possible aortic stenosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. 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.

  8. Genetic encoding of caged cysteine and caged homocysteine in bacterial and mammalian cells.

    PubMed

    Uprety, Rajendra; Luo, Ji; Liu, Jihe; Naro, Yuta; Samanta, Subhas; Deiters, Alexander

    2014-08-18

    We report the genetic incorporation of caged cysteine and caged homocysteine into proteins in bacterial and mammalian cells. The genetic code of these cells was expanded with an engineered pyrrolysine tRNA/tRNA synthetase pair that accepts both light-activatable amino acids as substrates. Incorporation was validated by reporter assays, western blots, and mass spectrometry, and differences in incorporation efficiency were explained by molecular modeling of synthetase-amino acid interactions. As a proof-of-principle application, the genetic replacement of an active-site cysteine residue with a caged cysteine residue in Renilla luciferase led to a complete loss of enzyme activity; however, upon brief exposure to UV light, a >150-fold increase in enzymatic activity was observed, thus showcasing the applicability of the caged cysteine in live human cells. A simultaneously conducted genetic replacement with homocysteine yielded an enzyme with greatly reduced activity, thereby demonstrating the precise probing of a protein active site. These discoveries provide a new tool for the optochemical control of protein function in mammalian cells and expand the set of genetically encoded unnatural amino acids.

  9. Cage-to-cage migration rates of Xe atoms in zeolite NaA from magnetization transfer experiments and simulations

    NASA Astrophysics Data System (ADS)

    Jameson, A. Keith; Jameson, Cynthia J.; Gerald, Rex E., II

    1994-08-01

    Xenon trapped in the alpha cages of zeolite NaA exhibits distinct NMR signals for clusters Xe1, Xe2, Xe3,..., up to Xe8. Using multisite magnetization transfer experiments, we have measured the rate constants kmn for the elementary processes that are involved in the cage-to-cage transfer of Xe atoms in the zeolite NaA, that is, for a single Xe atom leaving a cage containing Xen to appear in a neighboring cage containing Xem-1, thereby forming Xem. In a random walk simulation, these rate constants reproduce over a hundred magnetization decay/recovery curves that we have measured in four samples of Xe in zeolite NaA at room temperature, in selective inversion, and complementary experiments for all the significantly populated clusters. The simulations also lead to the correct experimental equilibrium distributions, that is, the fractions of the alpha cages containing Xe1,Xe2,...,Xe8.

  10. Insidious strut fractures in a DeBakey-Surgitool aortic valve prosthesis.

    PubMed

    Scott, S M; Sethi, G K; Paulson, D M; Takaro, T

    1978-04-01

    Recent reports of cage wear occurring in DeBakey-Surgitool aortic valve prostheses prompted us to examine with image intensification all our patients who have had this type of prosthesis implanted. One patient, who was asymptomatic, was discovered to have a prosthesis with two fractured struts. This patient's prosthetic valve was replaced successfully with a stented porcine heterograft prosthesis. Including the valve removed from this patient, 8 DeBakey-Surgitool aortic valves with structural defects have been reported to the manufacturer. In the absence of a catastrophic event, patients with valves having fractured or worn struts may be totally asymptomatic, and routine periodic roentgenographic examination may be the only way of detecting strut wear or fracture.

  11. [New aspects in aortic valve disease].

    PubMed

    Tornos, P

    2001-01-01

    Renewed interest for aortic valve disease has evolved in recent years. Aortic valve replacement has become the second most frequent cause of cardiac surgery, following coronary bypass surgery. In addition, the etiologic and physiopathologic knowledge of this disorder has improved. In the present paper we analyze three aspects of the disease which are, at present, the subject of study and controversy: first, we discuss the possible relationship between degenerative aortic stenosis and atherosclerosis; second, the involvement of the aortic root in cases of bicuspid aortic valve; and third, the surgical indications in asymptomatic patients with either aortic stenosis or regurgitation.

  12. 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.

  13. Rare or unusual causes of chronic, isolated, pure aortic regurgitation

    SciTech Connect

    Waller, B.F.; Taliercio, C.P.; Dickos, D.K.; Howard, J.; Adlam, J.H.; Jolly, W. )

    1990-08-01

    Six patients undergoing aortic valve replacement had rare or unusual causes of isolated, pure aortic regurgitation. Two patients had congenitally bicuspid aortic valves with a false commissure (raphe) displaced to the aortic wall (tethered bicuspid aortic valve), two had floppy aortic valves, one had a congenital quadricuspid valve, and one had radiation-induced valve damage.

  14. Computed Tomography Measurement of Rib Cage Morphometry in Emphysema

    PubMed Central

    Sverzellati, Nicola; Colombi, Davide; Randi, Giorgia; Pavarani, Antonio; Silva, Mario; Walsh, Simon L.; Pistolesi, Massimo; Alfieri, Veronica; Chetta, Alfredo; Vaccarezza, Mauro; Vitale, Marco; Pastorino, Ugo

    2013-01-01

    Background Factors determining the shape of the human rib cage are not completely understood. We aimed to quantify the contribution of anthropometric and COPD-related changes to rib cage variability in adult cigarette smokers. Methods Rib cage diameters and areas (calculated from the inner surface of the rib cage) in 816 smokers with or without COPD, were evaluated at three anatomical levels using computed tomography (CT). CTs were analyzed with software, which allows quantification of total emphysema (emphysema%). The relationship between rib cage measurements and anthropometric factors, lung function indices, and %emphysema were tested using linear regression models. Results A model that included gender, age, BMI, emphysema%, forced expiratory volume in one second (FEV1)%, and forced vital capacity (FVC)% fit best with the rib cage measurements (R2 = 64% for the rib cage area variation at the lower anatomical level). Gender had the biggest impact on rib cage diameter and area (105.3 cm2; 95% CI: 111.7 to 98.8 for male lower area). Emphysema% was responsible for an increase in size of upper and middle CT areas (up to 5.4 cm2; 95% CI: 3.0 to 7.8 for an emphysema increase of 5%). Lower rib cage areas decreased as FVC% decreased (5.1 cm2; 95% CI: 2.5 to 7.6 for 10 percentage points of FVC variation). Conclusions This study demonstrates that simple CT measurements can predict rib cage morphometric variability and also highlight relationships between rib cage morphometry and emphysema. PMID:23935872

  15. [Transcatheter aortic valve implantation for aortic stenosis. Initial experience].

    PubMed

    Careaga-Reyna, Guillermo; Lázaro-Castillo, José Luis; Lezama-Urtecho, Carlos Alberto; Macías-Miranda, Enriqueta; Dosta-Herrera, Juan José; Galván Díaz, José

    2016-12-09

    Aortic stenosis is a frequent disease in the elderly, and is associated with other systemic pathologies that may contraindicate the surgical procedure. Another option for these patients is percutaneous aortic valve implantation, which is less invasive. We present our initial experience with this procedure. Patients with aortic stenosis were included once selection criteria were accomplished. Under general anaesthesia and echocardiographic and fluosocopic control, a transcatheter aortic valve was implanted following s valvuloplasty. Once concluded the procedure, angiographic and pressure control was realized in order to confirm the valve function. Between November 2014 and May 2015, 6 patients were treated (4 males and 2 females), with a mean age of 78.83±5.66 years-old. The preoperative transvalvular gradient was 90.16±28.53mmHg and posterior to valve implant was 3.33±2.92mmHg (P<.05). Two patients had concomitant coronary artery disease which had been treated previously. One patient presented with acute right coronary artery occlusion which was immediately treated. However due to previous renal failure, postoperative sepsis and respiratory failure, the patient died one month later. It was concluded that our preliminary results showed that in selected patients percutaneous aortic valve implantation is a safe procedure with clinical improvement for treated patients. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

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

    PubMed

    Moore, Brandon L; Dasi, Lakshmi Prasad

    2015-09-01

    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.

  17. Aortic root replacement with a valve-sparing technique for quadricuspid aortic valve.

    PubMed

    Yamanaka, Katsuhiro; Okada, Kenji; Okita, Yutaka

    2015-04-01

    A 67-year old man with ascending aortic aneurysm was referred because of a quadricuspid aortic valve. He underwent aortic root replacement with a valve-sparing technique. Under deep hypothermic circulatory arrest, replacement of the ascending aorta was successfully performed. The postoperative course was uneventful without recurrence of aortic regurgitation.

  18. Spontaneous aortic dissection within an infrarenal AAA.

    PubMed

    Griffin, Kathryn J; Bailey, Marc A; McAree, Barry; Mekako, Anthony; Berridge, David C; Nicholson, Tony; Scott, D Julian A

    2012-12-01

    Aortic dissection occurring in the infrarenal abdominal aorta is uncommon. We present the case of a patient presenting with an enlarging abdominal aortic aneurysm and concurrent dissection (with associated radiological imaging) and briefly discuss the literature relating to this phenomenon.

  19. 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.

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

    DOEpatents

    Bowen, III, Daniel E.; Eastwood, Eric A [Raymore, MO

    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.

  1. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Maintenance of the CAGE file. (a) DLA Logistics Information Service will accept written requests for changes... electronic equivalent, to— DLA Logistics Information Service, DLIS-SBB, Federal Center, 74 Washington Avenue...) Additional guidance for maintaining CAGE codes is in Volume 7 of DoD 4100.39-M, Federal Logistics Information...

  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, 2011 CFR

    2011-10-01

    ... available at http://www.dlis.dla.mil/Forms/Form_AC135.asp. (2) If registration in the CCR database is not... (D) The Internet to access the CAGE Lookup Server at http://www.dlis.dla.mil/cage_welcome.asp....

  4. Structural analysis of aquaculture net cages in current

    NASA Astrophysics Data System (ADS)

    Moe, H.; Fredheim, A.; Hopperstad, O. S.

    2010-04-01

    A method for structural analysis of aquaculture net cages has been developed and verified for a netting solidity of 0.23, water current velocities from 0.1 to 0.5 m/s and relatively large deformations (volume reduction up to 70%) by comparing the numerical results to tests in a flume tank. Strength analysis was performed using commercial explicit finite element software to calculate distribution of loads in the net cage due to current, weights and gravity. The net cage was modelled using truss elements that represented several parallel twines. Sub-elements allowed the trusses to buckle in compression, and only negligible compressive forces were seen in the numerical results. Resulting drag loads and cage volume were shown to be dependent on the net cage size and weight system. Drag loads increased almost proportional to the current velocity for velocities in the range of 0.2-0.5 m/s, while the cage volume was reduced proportional to the current velocity. The calculated forces in ropes and netting of full-size net cages were well below the design capacity for current velocities up to 0.5 m/s. However, netting seams in the bottom panel of the net cage were identified as a potential problem area as the forces could reach the design capacity.

  5. Caged molecular beacons: controlling nucleic acid hybridization with light.

    PubMed

    Wang, Chunming; Zhu, Zhi; Song, Yanling; Lin, Hui; Yang, Chaoyong James; Tan, Weihong

    2011-05-28

    We have constructed a novel class of light-activatable caged molecular beacons (cMBs) that are caged by locking two stems with a photo-labile biomolecular interaction or covalent bond. With the cMBs, the nucleic acid hybridization process can be easily controlled with light, which offers the possibility for a high spatiotemporal resolution study of intracellular mRNAs.

  6. 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…

  7. Hydrogen-bond-driven controlled molecular marriage in covalent cages.

    PubMed

    Acharyya, Koushik; Mukherjee, Partha Sarathi

    2014-02-03

    A supramolecular approach that uses hydrogen-bonding interaction as a driving force to accomplish exceptional self-sorting in the formation of imine-based covalent organic cages is discussed. Utilizing the dynamic covalent chemistry approach from three geometrically similar dialdehydes (A, B, and D) and the flexible triamine tris(2-aminoethyl)amine (X), three new [3+2] self-assembled nanoscopic organic cages have been synthesized and fully characterized by various techniques. When a complex mixture of the dialdehydes and triamine X was subjected to reaction, it was found that only dialdehyde B (which has OH groups for H-bonding) reacted to form the corresponding cage B3X2 selectively. Surprisingly, the same reaction in the absence of aldehyde B yielded a mixture of products. Theoretical and experimental investigations are in complete agreement that the presence of the hydroxyl moiety adjacent to the aldehyde functionality in B is responsible for the selective formation of cage B3X2 from a complex reaction mixture. This spectacular selection was further analyzed by transforming a nonpreferred (non-hydroxy) cage into a preferred (hydroxy) cage B3X2 by treating the former with aldehyde B. The role of the H-bond in partner selection in a mixture of two dialdehydes and two amines has also been established. Moreover, an example of unconventional imine bond metathesis in organic cage-to-cage transformation is reported. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Maintenance of the CAGE file. (a) DLA Logistics Information Service will accept written requests for changes... electronic equivalent, to— DLA Logistics Information Service, DLIS-SBB, Federal Center, 74 Washington Avenue...) Additional guidance for maintaining CAGE codes is in Volume 7 of DoD 4100.39-M, Federal Logistics Information...

  9. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Maintenance of the CAGE file. (a) DLA Logistics Information Service will accept written requests for changes... electronic equivalent, to— DLA Logistics Information Service, DLIS-SBB, Federal Center, 74 Washington Avenue...) Additional guidance for maintaining CAGE codes is in Volume 7 of DoD 4100.39-M, Federal Logistics Information...

  10. 48 CFR 204.7204 - Maintenance of the CAGE file.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Maintenance of the CAGE file. (a) DLA Logistics Information Service will accept written requests for changes... electronic equivalent, to— DLA Logistics Information Service, DLIS-SBB, Federal Center, 74 Washington Avenue...) Additional guidance for maintaining CAGE codes is in Volume 7 of DoD 4100.39-M, Federal Logistics Information...

  11. 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...

  12. 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)

  13. 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)

  14. 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)

  15. Living in a cage is a restricted privilege.

    PubMed

    Fabbrizzi, Luigi

    2012-01-01

    There exist molecules, whose shape is reminiscent of a cage, that are able to include either metal ions or anions or both. In contrast to what happens in the macroscopic world, where a kinetic barrier prevents the escaping of the guest from the cage, the inclusion-extrusion of an ion from a molecular cage is in most cases thermodynamically controlled and the ion can get in or out of the cage at will. This gives the basis for highly selective ion recognition processes by cage-shaped ligands or receptors for metal ions and anions. Nobody in everyday life would say that a cage (for birds or wild animals), even if nicely designed and splendidly decorated, was beautiful and appealing, due to the consciousness of its reprehensible function. This does not happen in chemistry and we admire the ingenuity and skilfulness of synthetic chemists for the design of cage-shaped polycyclic hosts, made for the inclusion of a variety of guests, but also capable of generating in the viewer emotion and gratification of aesthetical origin. We have tried to outline, in this chapter, the development of cages in metal coordination chemistry and in anion coordination chemistry, over the last 50 years.

  16. 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.

  17. Abdominal aortic feminism.

    PubMed

    Mortimer, Alice Emily

    2014-11-14

    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. 2014 BMJ Publishing Group Ltd.

  18. Aortic Arch Interruption and Persistent Fifth Aortic Arch in Phace Syndrome: Prenatal Diagnosis and Postnatal Course.

    PubMed

    Chiappa, Enrico; Greco, Antonella; Fainardi, Valentina; Passantino, Silvia; Serranti, Daniele; Favilli, Silvia

    2015-09-01

    PHACE is a rare congenital neurocutaneous syndrome where posterior fossa malformations, hemangiomas, cerebrovascular anomalies, aortic arch anomalies, cardiac defects, and eye abnormalities are variably associated. We describe the prenatal detection and the postnatal course of a child with PHACE syndrome with a unique type of aortic arch anomaly consisting of proximal interruption of the aortic arch and persistence of the fifth aortic arch. The fifth aortic arch represented in this case a vital systemic-to-systemic connection between the ascending aorta and the transverse portion of the aortic arch allowing adequate forward flow through the aortic arch without surgical treatment.

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

    PubMed Central

    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

  20. 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.

  1. Management of bicuspid aortic valve with or without involvement of ascending aorta and aortic root.

    PubMed

    Neragi-Miandoab, S

    2014-06-01

    Patients with a bicuspid aortic valve (BAV) constitute a heterogeneous population with variable clinical presentation and complications. More than 50% of the patients who require aortic valve replacement have a BAV, a condition that may be associated with dilation of ascending aorta and aortic insufficiency caused by cusp disease or aortic root pathology. Of the potential BAV-related complications, dilation of the aortic root and ascending aorta are among the most serious. The dilation of ascending aorta and aortic root have been the subject of controversy. Whereas some surgeons believe that the dilation of the aorta is caused by the hemodynamic properties of the BAV, others believe that the dilation of the aortic root is secondary to genetic defects associated with the BAV. Management of a BAV should be tailored to each patient's clinical condition. The surgical approach varies from aortic valve replacement to combined aortic valve and root replacement to aortic-valve-sparing root replacement.

  2. Thoracic Aortic Aneurysm from Chronic Antiestrogen Therapy.

    PubMed

    Tripathi, Rishi; Sainathan, Sandeep; Ziganshin, Bulat A; Elefteriades, John A

    2017-03-01

    Aortic aneurysms are a common but often undetected pathology prevalent in the population. They are often detected as incidental findings on imaging studies performed for unrelated pathologies. Estrogens have been shown to exert a protective influence on aortic tissue. Pharmacological agents blocking the actions of estrogens may thus be implicated in causing aortic pathologies. We present the case of an elderly woman with breast carcinoma treated for 18 years with antiestrogen therapy who subsequently developed acute thoracic aortic deterioration (enlargement and wall disruption).

  3. Photoactivatable Caged Prodrugs of VEGFR-2 Kinase Inhibitors.

    PubMed

    Pinchuk, Boris; Horbert, Rebecca; Döbber, Alexander; Kuhl, Lydia; Peifer, Christian

    2016-04-29

    In this study, we report on the design, synthesis, photokinetic properties and in vitro evaluation of photoactivatable caged prodrugs for the receptor tyrosine kinase VEGFR-2. Highly potent VEGFR-2 inhibitors 1 and 3 were caged by introduction of a photoremovable protecting group (PPG) to yield the caged prodrugs 4 and 5. As expected, enzymatic and cellular proliferation assays showed dramatically diminished efficacy of caged prodrugs in vitro. Upon ultraviolet (UV) irradiation of the prodrugs original inhibitory activity was completely restored and even distinctly reinforced, as was the case for the prodrug 4. The presented results are a further evidence for caging technique being an interesting approach in the protein kinase field. It could enable spatial and temporal control for the inhibition of VEGFR-2. The described photoactivatable prodrugs might be highly useful as biological probes for studying the VEGFR-2 signal transduction.

  4. Evaluation of the effects of cage height and stocking density on the behaviour of laying hens in furnished cages.

    PubMed

    Albentosa, M J; Cooper, J J; Luddem, T; Redgate, S E; Elson, H A; Walker, A W

    2007-02-01

    1. Limited information is available on how changes in horizontal and vertical space within enriched or furnished layer cages (as defined by Directive 1999/74/EC) influence hen behaviour. This study evaluated the effects of varying minimum cage heights and space allowances on the behaviour of laying hens housed in furnished cages. It was conducted on two flocks of medium brown hybrid hens housed in furnished cages with access to perches and nest boxes on a semi-commercial scale at ADAS Gleadthorpe. 2. Flock 1 consisted of two layer strains (ISA Brown and Babcock 380), housed at two minimum cage heights (38 and 45 cm) and 5 stocking densities between 609 and 870 cm2/bird, with 12 replicates of each of the 20 strain/cage height/stocking density treatment combinations. Stocking density was varied by varying the number of birds per cage from 10 to 7 in standard full-width cages or housing 7 hens in a narrower cage. As a consequence stocking density, group size and trough width per bird co-varied for 4 out of 5 stocking density treatments. 3. Behaviour of flock 1 was sampled at 33 to 36, 46 and 68 weeks of age. At each age one top-tier, one middle-tier and one bottom-tier cage was sampled for each treatment. 4. Few behavioural differences due to cage treatments were detected. Hens at 870 cm2 had shorter feeding bouts than hens at 609 and 762 cm2. Yawning was more common in the cages with greater cage height. 5. Video recordings of flock 1 examined cage height effects on hens' use of vertical space and provided additional data on stretching and self-maintenance activities. No differences in behaviour between 38 and 45 cm cages were found except that scratching head was more common in cages with greater cage height. 6. Flock 2 consisted of two layer strains (Shaver Brown and Hy-Line Brown), housed at 38 and 45 cm and 609, 762 and 1016 cm2/bird, with 18 replicates of each of the 12 strain/cage height/stocking density treatment combinations. Stocking density was varied by

  5. 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

  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. Photocatalyzed oxidation of hydrocarbons in zeolite cages

    SciTech Connect

    Frei, H.; Blatter, F.; Sun, H.

    1996-06-01

    Oxidation of hydrocarbons by molecular oxygen is a key process in chemical industry. But reactions that use O{sub 2} as the primary oxidant often produce large amounts of unwanted byproducts. One major reason that selectivities are low is that the desired products (such as alcohols or carbonyls) are more easily oxidized by O{sub 2} than the parent hydrocarbon. The authors recently discovered a simple method that gives partial oxidation of small alkenes, alkanes, and alkyl-substituted benzenes by O{sub 2} at unprecedented selectivity, even at high conversion of the hydrocarbon. The approach is based on visible light-induced chemistry of hydrocarbon-O{sub 2} collisional pairs in the cages of large-pore zeolites. Reactions are conducted at ambient temperature in the absence of solvent or photosensitizer. Here the authors describe the most interesting reactions established thus far and define issues that pertain to scale-up of the method.

  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. 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).

  10. A novel vented microisolation container for caging animals: microenvironmental comfort in a closed-system filter cage.

    PubMed

    Rivard, G F; Neff, D E; Cullen, J F; Welch, S W

    2000-01-01

    We designed a closed-system cage with vent ports that would allow continuous airflow in the occupied cage to ensure adequate ventilation and gas exchange. In this system, the metabolic heat loads of mice generate upward thermal air currents. Heat exits via the exhaust port, and room air enters via the intake port, providing adequate ventilation. Simulations based on computational fluid dynamics (CFD) helped us to optimize the cage's design. CFD simulations and smoke visualizations with a feeder-trough assembly illustrated the one-pass air circulation pattern and the lack of air recirculation, turbulence, and dead air space in our system. We used hot-film anemometry and smoke-test methodologies to show that adequate ventilation was provided. In a room with still air (0 air changes per hour [ACH]), a cage fitted with double wire-cloth filters (40 mesh size) and occupied by five mice has at least 12 ACH, whereas the same cage occupied by one mouse has 6 ACH. After five mice had occupied the cage for a week, its average temperature was 0.58C, relative humidity was 34%, and ammonia concentration was 3 ppm higher than that of the room. Our novel vented microisolation cage provides adequate intracage ACH, isolates mice from environmental contaminants, and contains allergenic particles within the cage in an environment appropriate for the species.

  11. Balloon aortic valvuloplasty as a bridge to aortic valve replacement in a patient with severe calcific aortic stenosis

    PubMed Central

    Swinkels, B.M.; Jaarsma, W.; Wely, L. Relik-van; van Swieten, H.A.; Ernst, J.M.P.G.; Plokker, H.W.M.

    2003-01-01

    This case report describes a patient with severe calcific aortic stenosis who was initially considered inoperable because of a very poor left ventricular function and severe pulmonary hypertension. After balloon aortic valvuloplasty, the clinical and haemodynamic status of the patient improved to such an extent that subsequent aortic valve replacement was considered possible and eventually proved to be successful. Balloon aortic valvuloplasty has value as a potential bridge to aortic valve replacement when the risks for surgery are considered to be too high. ImagesFigure 1 PMID:25696195

  12. [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.

  13. 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

  14. Social discrimination of cage-mates and non-cage-mates by rats.

    PubMed

    Jones, Samantha; Burman, Oliver; Mendl, Michael

    2014-07-01

    The ability to discriminate between group-mates and non-group-mates likely underpins the occurrence of affiliative and aggressive behaviour towards 'in-group' and 'out-group' individuals. Here we present two experiments aimed at testing the ability of rats (Rattus norvegicus) to discriminate between cage-mate (CM: animals residing in the subject's home cage) and non-cage-mate (NCM) conspecifics. In experiment 1, rats were trained to discriminate between different exemplars of CM and NCM using a lever pressing task employing symmetrical reinforcement. Subjects did not reach performance criterion, but they did show some evidence of discrimination between the two types of stimuli. In experiment 2, we employed a digging task to determine if rats can discriminate between odour cues from CM and NCM presented simultaneously on two sand-filled bowls. Subjects reached performance criterion on the first pair of odours, and on three more different pairs of CM and NCM odours. The results of a reversal task, using a fifth pair of odours, indicate that the rats were using a common factor to discriminate between social cues from CM and NCM conspecifics, rather than learning each pair independently. Possible candidates include a group-specific odour cue, or the development of a CM/NCM category concept.

  15. Severe aortic stenosis: forgotten associations.

    PubMed

    Godinho, Ana Rita; Amorim, Sandra; Campelo, Manuel; Martins, Elisabete; Lopez Rodriguez, Elisa; Coelho, Rosa; Macedo, Guilherme; Maciel, Maria Júlia

    2014-09-01

    The authors present the case of a 68-year-old man with predominantly right heart failure in the context of severe aortic stenosis associated with pulmonary hypertension. Anemia was diagnosed which, after endoscopic study, was considered to be secondary to angiodysplasia and a diagnosis of Heyde syndrome was made. After valve replacement surgery the patient's heart failure improved and hemoglobin levels stabilized. We present this case to show the need to recognize less common associations of severe aortic stenosis, in order to provide immediate and appropriate treatment.

  16. Aortic and other arterial injuries.

    PubMed

    Hardy, J D; Raju, S; Neely, W A; Berry, D W

    1975-05-01

    Three hundred sixty arterial injuries in 353 patients are reviewed. They covered a wide spectrum of injuries and included 36 aortic injuries and 19 cases of carotid truama. The mortality rate of 12% was in large part due to aortic injuries. Shock was the predominant cause of death. Infection was the most frequent non-fatal complication. Pulmonary complications were surprisingly uncommon. With methods and techniques discussed in the paper, 90% satisfactory end results were achieved. The amputation rate was 6% where extremity injuries were involved.

  17. Aortic and other arterial injuries.

    PubMed Central

    Hardy, J D; Raju, S; Neely, W A; Berry, D W

    1975-01-01

    Three hundred sixty arterial injuries in 353 patients are reviewed. They covered a wide spectrum of injuries and included 36 aortic injuries and 19 cases of carotid truama. The mortality rate of 12% was in large part due to aortic injuries. Shock was the predominant cause of death. Infection was the most frequent non-fatal complication. Pulmonary complications were surprisingly uncommon. With methods and techniques discussed in the paper, 90% satisfactory end results were achieved. The amputation rate was 6% where extremity injuries were involved. Images Fig. 11. Fig. 13. PMID:1130881

  18. Predictive risk models for proximal aortic surgery

    PubMed Central

    Díaz, Rocío; Pascual, Isaac; Álvarez, Rubén; Alperi, Alberto; Rozado, Jose; Morales, Carlos; Silva, Jacobo; Morís, César

    2017-01-01

    Predictive risk models help improve decision making, information to our patients and quality control comparing results between surgeons and between institutions. The use of these models promotes competitiveness and led to increasingly better results. All these virtues are of utmost importance when the surgical operation entails high-risk. Although proximal aortic surgery is less frequent than other cardiac surgery operations, this procedure itself is more challenging and technically demanding than other common cardiac surgery techniques. The aim of this study is to review the current status of predictive risk models for patients who undergo proximal aortic surgery, which means aortic root replacement, supracoronary ascending aortic replacement or aortic arch surgery. PMID:28616348

  19. Predictive risk models for proximal aortic surgery.

    PubMed

    Hernandez-Vaquero, Daniel; Díaz, Rocío; Pascual, Isaac; Álvarez, Rubén; Alperi, Alberto; Rozado, Jose; Morales, Carlos; Silva, Jacobo; Morís, César

    2017-05-01

    Predictive risk models help improve decision making, information to our patients and quality control comparing results between surgeons and between institutions. The use of these models promotes competitiveness and led to increasingly better results. All these virtues are of utmost importance when the surgical operation entails high-risk. Although proximal aortic surgery is less frequent than other cardiac surgery operations, this procedure itself is more challenging and technically demanding than other common cardiac surgery techniques. The aim of this study is to review the current status of predictive risk models for patients who undergo proximal aortic surgery, which means aortic root replacement, supracoronary ascending aortic replacement or aortic arch surgery.

  20. Acute aortic dissection at two extreme ages.

    PubMed

    Ramzisham, A R M; Arief, H; Ngoo, K S; Zamrin, D M; Joanna, O S M

    2011-01-01

    Acute aortic dissection is a life-threatening condition, warranting prompt diagnosis and treatment. Management of which incorporates multidisciplinary expertise from the medical, surgical and intensive care. If left untreated, the mortality rate of acute aortic disease exceeds 50% within 48 hours and 80% within two weeks, with a 5-year survival rate of 19%. The most common cause of death in untreated acute aortic dissection, regardless of aetiology, is aortic rupture. We would like to share our successful experience of cases at the two extreme ages of acute aortic dissection. Literature review with their pathogenesis are discussed.

  1. MMP-2 Isoforms in Aortic Tissue and Serum of Patients with Ascending Aortic Aneurysms and Aortic Root Aneurysms

    PubMed Central

    Tscheuschler, Anke; Meffert, Philipp; Beyersdorf, Friedhelm; Heilmann, Claudia; Kocher, Nadja; Uffelmann, Xenia; Discher, Philipp; Siepe, Matthias; Kari, Fabian A.

    2016-01-01

    Objective The need for biological markers of aortic wall stress and risk of rupture or dissection of ascending aortic aneurysms is obvious. To date, wall stress cannot be related to a certain biological marker. We analyzed aortic tissue and serum for the presence of different MMP-2 isoforms to find a connection between serum and tissue MMP-2 and to evaluate the potential of different MMP-2 isoforms as markers of high wall stress. Methods Serum and aortic tissue from n = 24 patients and serum from n = 19 healthy controls was analyzed by ELISA and gelatin zymography. 24 patients had ascending aortic aneurysms, 10 of them also had aortic root aneurysms. Three patients had normally functioning valves, 12 had regurgitation alone, eight had regurgitation and stenosis and one had only stenosis. Patients had bicuspid and tricuspid aortic valves (9/15). Serum samples were taken preoperatively, and the aortic wall specimen collected during surgical aortic repair. Results Pro-MMP-2 was identified in all serum and tissue samples. Pro-MMP-2 was detected in all tissue and serum samples from patients with ascending aortic/aortic root aneurysms, irrespective of valve morphology or other clinical parameters and in serum from healthy controls. We also identified active MMP-2 in all tissue samples from patients with ascending aortic/aortic root aneurysms. None of the analyzed serum samples revealed signals relatable to active MMP-2. No correlation between aortic tissue total MMP-2 or tissue pro-MMP-2 or tissue active MMP-2 and serum MMP-2 was found and tissue MMP-2/pro-MMP-2/active MMP-2 did not correlate with aortic diameter. This evidence shows that pro-MMP-2 is the predominant MMP-2 species in serum of patients and healthy individuals and in aneurysmatic aortic tissue, irrespective of aortic valve configuration. Active MMP-2 species are either not released into systemic circulation or not detectable in serum. There is no reliable connection between aortic tissue—and serum MMP-2

  2. Transcatheter aortic-valve replacement for inoperable severe aortic stenosis.

    PubMed

    Makkar, Raj R; Fontana, Gregory P; Jilaihawi, Hasan; Kapadia, Samir; Pichard, Augusto D; Douglas, Pamela S; Thourani, Vinod H; Babaliaros, Vasilis C; Webb, John G; Herrmann, Howard C; Bavaria, Joseph E; Kodali, Susheel; Brown, David L; Bowers, Bruce; Dewey, Todd M; Svensson, Lars G; Tuzcu, Murat; Moses, Jeffrey W; Williams, Matthew R; Siegel, Robert J; Akin, Jodi J; Anderson, William N; Pocock, Stuart; Smith, Craig R; Leon, Martin B

    2012-05-03

    Transcatheter aortic-valve replacement (TAVR) is the recommended therapy for patients with severe aortic stenosis who are not suitable candidates for surgery. The outcomes beyond 1 year in such patients are not known. We randomly assigned patients to transfemoral TAVR or to standard therapy (which often included balloon aortic valvuloplasty). Data on 2-year outcomes were analyzed. A total of 358 patients underwent randomization at 21 centers. The rates of death at 2 years were 43.3% in the TAVR group and 68.0% in the standard-therapy group (P<0.001), and the corresponding rates of cardiac death were 31.0% and 62.4% (P<0.001). The survival advantage associated with TAVR that was seen at 1 year remained significant among patients who survived beyond the first year (hazard ratio, 0.58; 95% confidence interval [CI], 0.36 to 0.92; P=0.02 with the use of the log-rank test). The rate of stroke was higher after TAVR than with standard therapy (13.8% vs. 5.5%, P=0.01), owing, in the first 30 days, to the occurrence of more ischemic events in the TAVR group (6.7% vs. 1.7%, P=0.02) and, beyond 30 days, to the occurrence of more hemorrhagic strokes in the TAVR group (2.2% vs. 0.6%, P=0.16). At 2 years, the rate of rehospitalization was 35.0% in the TAVR group and 72.5% in the standard-therapy group (P<0.001). TAVR, as compared with standard therapy, was also associated with improved functional status (P<0.001). The data suggest that the mortality benefit after TAVR may be limited to patients who do not have extensive coexisting conditions. Echocardiographic analysis showed a sustained increase in aortic-valve area and a decrease in aortic-valve gradient, with no worsening of paravalvular aortic regurgitation. Among appropriately selected patients with severe aortic stenosis who were not suitable candidates for surgery, TAVR reduced the rates of death and hospitalization, with a decrease in symptoms and an improvement in valve hemodynamics that were sustained at 2 years of

  3. Cage design and configuration for an arboreal species of primate.

    PubMed

    Williams, L E; Abee, C R; Barnes, S R; Ricker, R B

    1988-06-01

    The squirrel monkey (genus Saimiri) is an arboreal primate from equatorial South America. This species forms large social groups that consist of multiple females and males of varying ages, from infant to adult. As the use of squirrel monkeys in research continues to grow, an understanding of optimal cage design and environment is essential. The University of South Alabama Primate Research Laboratory houses a breeding colony of 350 squirrel monkeys. Each group cage, measuring 4.5 X 2.5 X 1.5 meters, can contain up to 20 animals. A breeding group consists of one adult male, eight to ten adult females, and varying numbers of infant and juvenile animals. In order to determine the most suitable cage environment for the squirrel monkey, a series of studies were carried out to compare various perch materials and cage configurations. Squirrel monkeys preferred a poly-vinyl-chloride pipe perch (rigid) over rope perches (non-rigid). When provided with multiple levels of perches, all levels were used. Males tended to distribute their activities randomly at different levels. In a two tiered perch arrangement, females concentrated 67% of their social activity on the top tier. In a triple tier configuration, females concentrated 66% of their travel on the top tier. These results indicate that by creating a cage environment with multiple tiers of horizontal perches the effective cage space can be doubled or tripled. This provides an effective means of reducing population density without enlarging the dimensions of the cage or reducing social group size.

  4. Biomechanical analysis of cages for posterior lumbar interbody fusion.

    PubMed

    Fantigrossi, Alfonso; Galbusera, Fabio; Raimondi, Manuela Teresa; Sassi, Marco; Fornari, Maurizio

    2007-01-01

    Interbody fusions using intervertebral cages have become increasingly common in spinal surgery. Computational simulations were conducted in order to compare different cage designs in terms of their biomechanical interaction with the spinal structures. Differences in cage design and surgical technique may significantly affect the biomechanics of the fused spine segment, but little knowledge is available on this topic. In the present study, four 3D finite element models were developed, reproducing the human L4-L5 spinal unit in intact condition and after implantation of three different cage models. The intact model consisted of two vertebral bodies and relevant laminae, facet joints, main ligaments and disc. The instrumented models reproduced the post-operative conditions resulting after implant of the different cages. The three considered devices were hollow threaded titanium cages, the BAK (Zimmer Centerpulse, Warsaw, IN, USA), the Interfix and the Interfix Fly (both by Medtronic Sofamor Danek, Memphis, TN, USA). Simulations were run imposing various loading conditions, under a constant compressive preload. A great increase in the stiffness induced on the spinal segment by all cages was observed in all the considered loading cases. Stress distributions on the bony surface were evaluated and discussed. The differences observed between the biomechanics of the instrumented models were associated with the geometrical and surgical features of the devices.

  5. Preliminary in vivo study of an intra-aortic impeller pump driven by an extracorporeal whirling magnet.

    PubMed

    Li, Guorong; Zhao, Hong; Zhu, Xiaodong; Ren, Bing

    2002-10-01

    To achieve the aim of long-term heart-assist with a simple implantable device, we have been trying to develop a minimal intra-aortic impeller blood pump driven by an extracorporeal magnetic device. The purpose of the current study was to evaluate its feasibility by acute in vivo animal tests. The minimal intra-aortic pump was a cage-supported rotor-impeller, 17 mm in diameter with a total length of 30 mm. The driving magnet, mounted extracorporeally, was 55 mm in diameter and 50 mm in length. Seventeen dogs weighing from 28-34 kg were used in the study. After thoracic incision, heparin (50 U/kg) was infused. The impeller pump was inserted into the aortic chamber via a prosthetic vessel and fastened. Thin tubes were inserted into the left ventricular apex and the femoral artery to monitor the left ventricular (LV) and the aortic pressure. After closing the thoracic cavity, the extracorporeal whirling magnet, turned by an electric motor, was placed tightly against the thoracic wall parallel to the intra-aortic pump. The experiments, each lasting for about 40 min, were successful in 7 animals; the other 10 animals died of bleeding during pump implantation and were excluded from the experiment. The peak systolic pressure of the left ventricle could be considerably decreased by the pump and was reduced to as low as 28 mm Hg at a rotational speed of 9,000 rpm, showing that the simple intra-aortic impeller was effective in unloading the natural heart. The novel left ventricular assist device (LVAD) concept of an intra-aortic impeller pump, driven by an extracorporeal magnetic device, is feasible.

  6. Development of human hepatocellular carcinoma cell-targeted protein cages.

    PubMed

    Toita, Riki; Murata, Masaharu; Tabata, Shigekazu; Abe, Kana; Narahara, Sayoko; Piao, Jing Shu; Kang, Jeong-Hun; Hashizume, Makoto

    2012-07-18

    We described herein a human hepatocellular carcinoma (HCC) cell-targeted protein cage for which the HCC-binding peptide termed SP94 was modified at the surface of a naturally occurred heat shock protein (Hsp) cage. Six types of HCC-targeted Hsp cages were chemically synthesized using two types of heterobifunctional linker (SM(PEG)(n)) with different lengths and two types of SP94 peptide, which contained a unique Cys residue at the N- or C-terminus of the peptide. These Hsp cages were characterized using matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-ToF MS) analyses, sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analyses, and dynamic light scattering (DLS) measurement. Fluorescence microscopic observations revealed that all the engineered protein cages bind selectively to HCC cells but not to the other cell lines tested (including normal liver cell). Moreover, the number of SP94 peptides on Hsp cages, conjugation site of SP94 peptide, and linker length between a Hsp cage and a SP94 peptide had important effects upon the binding of engineered Hsp cages to HCC cells. An engineered Hsp cage conjugated to the N-terminus of SP94 peptide via a longer linker molecule and containing high SP94 peptide levels showed greater binding toward HCC cells. Surprisingly, through optimization of these three factors, up to 10-fold greater affinity toward HCC cells was achieved. These results are critically important not only for the development of HCC cell-targeting devices using SP94 peptide, but also to create other cell-targeting materials that utilize other peptide ligands.

  7. Aortic Wall Injury Related to Endovascular Therapy for Aortic Coarctation.

    PubMed

    Tretter, Justin T; Jones, Thomas K; McElhinney, Doff B

    2015-09-01

    Aortic wall complications can occur in unrepaired aortic coarctation (CoA) and after surgical repair or endovascular treatment. This review summarizes the available literature and current understanding of aortic wall injury (AWI) surrounding the management of CoA, focusing specifically on acute and follow-up AWI after endovascular treatment. There have been 23 reported cases of aortic rupture after endovascular treatment for CoA, including angioplasty alone, bare metal stenting, and primary covered stent therapy. Even if these published cases represent only a minority of ruptures that have actually occurred, the incidence is substantially <1%. The incidence of acute aneurysm formation was 0% to 13% after angioplasty, 0% to 5% after bare metal stent placement, and <1% after covered stent placement. The reported incidence and natural history of both acute and new AWI during follow-up after endovascular therapy for CoA varies considerably, likely secondary to ascertainment and reporting biases and inconsistent definitions. Although important AWI after endovascular treatment of CoA seems to be declining in frequency with increasing experience and improving technology, it remains one of the most important potential adverse outcomes. Long-term surveillance for new AWI and monitoring of existing AWI is mandatory, with institution of appropriate treatment when necessary. A central research focus in this population should be determination of the appropriate treatment for both native and recurrent CoA across various ages with regard to limiting recurrent CoA and preventing associated aortic wall complications, in addition to determining the appropriate treatment of various AWI. Consistent definitions and reporting are necessary to truly understand the incidence of, risk factors for, and measures protective against AWI after angioplasty or stent implantation for CoA.

  8. Genetic and Epigenetic Regulation of Aortic Aneurysms

    PubMed Central

    Kim, Ha Won

    2017-01-01

    Aneurysms are characterized by structural deterioration of the vascular wall leading to progressive dilatation and, potentially, rupture of the aorta. While aortic aneurysms often remain clinically silent, the morbidity and mortality associated with aneurysm expansion and rupture are considerable. Over 13,000 deaths annually in the United States are attributable to aortic aneurysm rupture with less than 1 in 3 persons with aortic aneurysm rupture surviving to surgical intervention. Environmental and epidemiologic risk factors including smoking, male gender, hypertension, older age, dyslipidemia, atherosclerosis, and family history are highly associated with abdominal aortic aneurysms, while heritable genetic mutations are commonly associated with aneurysms of the thoracic aorta. Similar to other forms of cardiovascular disease, family history, genetic variation, and heritable mutations modify the risk of aortic aneurysm formation and provide mechanistic insight into the pathogenesis of human aortic aneurysms. This review will examine the relationship between heritable genetic and epigenetic influences on thoracic and abdominal aortic aneurysm formation and rupture. PMID:28116311

  9. Aortic Root Enlargement or Sutureless Valve Implantation?

    PubMed Central

    Baikoussis, Nikolaos G.; Dedeilias, Panagiotis; Argiriou, Michalis

    2016-01-01

    Aortic valve replacement (AVR) in patients with a small aortic annulus is a challenging issue. The importance of prosthesis–patient mismatch (PPM) post aortic valve replacement (AVR) is controversial but has to be avoided. Many studies support the fact that PPM has a negative impact on short and long term survival. In order to avoid PPM, aortic root enlargement may be performed. Alternatively and keeping in mind that often some comorbidities are present in old patients with small aortic root, the Perceval S suturelles valve implantation could be a perfect solution. The Perceval sutureless bioprosthesis provides reasonable hemodynamic performance avoiding the PPM and providing the maximum of aortic orifice area. We would like to see in the near future the role of the aortic root enlargement techniques in the era of surgical implantation of the sutureless valve (SAVR) and the transcatheter valve implantation (TAVI). PMID:28028424

  10. Notch-dependent EMT is attenuated in patients with aortic aneurysm and bicuspid aortic valve.

    PubMed

    Kostina, Aleksandra S; Uspensky, Vladimir Е; Irtyuga, Olga B; Ignatieva, Elena V; Freylikhman, Olga; Gavriliuk, Natalia D; Moiseeva, Olga M; Zhuk, Sergey; Tomilin, Alexey; Kostareva, Аnna А; Malashicheva, Anna B

    2016-04-01

    Bicuspid aortic valve is the most common congenital heart malformation and the reasons for the aortopathies associated with bicuspid aortic valve remain unclear. NOTCH1 mutations are associated with bicuspid aortic valve and have been found in individuals with various left ventricular outflow tract abnormalities. Notch is a key signaling during cardiac valve formation that promotes the endothelial-to-mesenchymal transition. We address the role of Notch signaling in human aortic endothelial cells from patients with bicuspid aortic valve and aortic aneurysm. Aortic endothelial cells were isolated from tissue fragments of bicuspid aortic valve-associated thoracic aortic aneurysm patients and from healthy donors. Endothelial-to-mesenchymal transition was induced by activation of Notch signaling. Effectiveness of the transition was estimated by loss of endothelial and gain of mesenchymal markers by immunocytochemistry and qPCR. We show that aortic endothelial cells from the patients with aortic aneurysm and bicuspid aortic valve have down regulated Notch signaling and fail to activate Notch-dependent endothelial-to-mesenchymal transition in response to its stimulation by different Notch ligands. Our findings support the idea that bicuspid aortic valve and associated aortic aneurysm is associated with dysregulation of the entire Notch signaling pathway independently on the specific gene mutation.

  11. 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.

  12. Isolation and metabolism cage system for newborn pigs.

    PubMed

    Songer, J R; Mathis, R G; Skartvedt, S M

    1976-03-01

    An isolation system was designed and constructed for isolating normal and infected newborn pigs. The system consisted of an outer cage fitted with a biological diffusion filter and a dunk bath entry system and an inner metabolism cage to contain the pig. When tested with S-13 bacteriophage, the isolation and metabolism cage system was at least 99% efficient in preventing the entry or escape of microorganism. A total of 267 Escherichia coli-infected newborn pigs have been isolated in these units, with no cross contaminations.

  13. Triple cage olfactometer for evaluating mosquito (Diptera: Culicidae) attraction responses.

    PubMed

    Posey, K H; Barnard, D R; Schreck, C E

    1998-05-01

    A triple cage olfactometer for evaluating mosquito attraction responses is described. The olfactometer is designed for easy access for interior cleaning, has a mechanism that allows synchronous operation of the port doors on each cage, and requires 0.8 m2 of floor space. It is constructed of clear acrylic, contains 3 test chambers in a tiered configuration, has paired removable sleeves and mosquito traps on each cage, and is equipped with a filtered external air supply system that has temperature and relative humidity control.

  14. Migration of hydrogen radicals through clathrate hydrate cages

    NASA Astrophysics Data System (ADS)

    Alavi, Saman; Ripmeester, John A.

    2009-09-01

    Electronic structure calculations are used to determine energy barriers to hydrogen radical migration in structure II clathrate small and large cages. Migration of H-radicals through pentagonal and hexagonal faces of small and large cages are considered and energies barriers calculated at the MP2 level with the 6-311++G( d, p) basis set are 61 and 17 kJ mol -1, respectively. Energy barriers (with tunneling corrections) are used to estimate escape rates from the cages and to explain results of recent experiments on the transformation of n-propyl radical in the propane hydrate and the behavior of hydrogen radicals in tetrahydrofuran/H 2 hydrates.

  15. 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.

  16. Prognostic significance of mild aortic regurgitation in predicting mortality after transcatheter aortic valve replacement.

    PubMed

    Jones, Brandon M; Tuzcu, E Murat; Krishnaswamy, Amar; Popovic, Zoran; Mick, Stephanie; Roselli, Eric E; Gul, Sajjad; Devgun, Jasneet; Mistry, Sohi; Jaber, Wael A; Svensson, Lars G; Kapadia, Samir R

    2016-09-01

    Moderate to severe aortic regurgitation after transcatheter aortic valve replacement is associated with worse outcomes. The impact of mild aortic regurgitation has been less clear, possibly because of the broad categories that have been used in clinical trials, but holds increasing importance in the study of next-generation devices in low- and intermediate-risk cohorts. A more granular scheme, which is common in clinical practice and proposed for future trials, may add prognostic value. We evaluated all patients undergoing transfemoral transcatheter aortic valve replacement at the Cleveland Clinic from 2006 to 2012. The degree of aortic regurgitation after transcatheter aortic valve replacement was reported from the echocardiography database based on a clinical, transthoracic echocardiogram performed within 30 days of the procedure. Aortic regurgitation was finely discriminated on the basis of a multiwindow, multiparametric, integrative approach using our usual clinical scale: none, trivial to 1+, 1+, 1 to 2+, 2+, 2 to 3+, 3+, 3 to 4+, or 4+. There were 237 patients included in the analysis. By controlling for age, gender, Society of Thoracic Surgeons score, baseline ejection fraction, and aortic regurgitation before transcatheter aortic valve replacement, there was a significant increase in mortality for each half grade of aortic regurgitation compared with the complete absence of aortic regurgitation after transcatheter aortic valve replacement. The unit hazard ratio for each 1+ increase in aortic regurgitation after transcatheter aortic valve replacement was 2.26 (95% confidence interval, 1.48-3.43; P < .001) considering aortic regurgitation as a continuous variable. Other clinical variables did not significantly affect mortality. Even mild aortic regurgitation after transcatheter aortic valve replacement is associated with worse long-term mortality. There may be prognostic value in reporting milder categories of aortic regurgitation with more granular

  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. Critical aortic stenosis and acute ascending aortic penetrating ulcer managed utilizing transapical TAVR and TEVAR.

    PubMed

    Allen, Keith B; Davis, J Russell; Cohen, David J

    2015-10-01

    Thoracic endovascular aortic repair (TEVAR) of acute ascending aortic pathology is feasible; however, the unique features of this aortic segment in addition to access challenges restricts its use to a select, high-risk subset of patients. With the advent of TAVR, large device delivery using transapical access has become a well-defined technique. We report a patient with critical aortic stenosis and an acute ascending aortic penetrating ulcer with tamponade managed successfully utilizing transapical TAVR and TEVAR. To our knowledge, this is the first reported case of a hybrid single-stage TAVR and ascending aortic TEVAR using transapical access.

  19. Cage Compounds as Potential Energetic Oxidizers: A Theoretical Study of a Cage Isomer of N2O3

    DTIC Science & Technology

    2014-07-01

    Oxidizers: A Theoretical Study of a Cage Isomer of N2O3 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Robert J...investigate the cage isomer of N2O3 (c-N2O3) as a viable energetic oxidizer. c-N2O3 is vibrationally stable with a large heat of formation of 7.95 kJ...of a Cage Isomer of N2O3 Robert J. Buszek[a] and Jerry A. Boatz*[b] Abstract: Ab initio electronic structure calculations are employed to investigate

  20. 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.

  1. 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.

  2. 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.

  3. Ultrafast protein folding in cages and zippers

    NASA Astrophysics Data System (ADS)

    Qiu, Linlin; Hagen, Stephen J.

    2003-03-01

    The smallest, fastest-folding proteins fold on the ˜μ s time scale, where state-of-the-art molecular dynamics (MD) simulation can finally overlap with the fastest experimental probes such as laser temperature-jump spectroscopy. For such proteins, one can now ask whether molecular dynamics correctly predicts the native structure and/or the folding speed. We will present experimental measurements of folding speed in two small proteins that acquire a stable tertiary fold rapidly enough to have been simulated in MD: (a) The 20-residue tryptophan (Trp) cage, which constitutes both the smallest truly protein-like molecule and also the fastest-folding [Neidigh et al., Nat. Struct. Biol. 9 425 (2002); Qiu et al., JACS 124 12952 (2002)], and (b) the 12-residue Trp zippers (e.g. TrpZip1), monomeric β-hairpins engineered by Cochran et al. [PNAS 98 5578 (2001)]. Both proteins fold in a cooperative, two-state transition at rates exceeding 10^5 s-1 (τ < 10 μs). We will compare the folding kinetics of these proteins with the predictions of MD simulations.

  4. Multiexpandable cage for minimally invasive posterior lumbar interbody fusion

    PubMed Central

    Coe, Jeffrey D; Zucherman, James F; Kucharzyk, Donald W; Poelstra, Kornelis A; Miller, Larry E; Kunwar, Sandeep

    2016-01-01

    The increasing adoption of minimally invasive techniques for spine surgery in recent years has led to significant advancements in instrumentation for lumbar interbody fusion. Percutaneous pedicle screw fixation is now a mature technology, but the role of expandable cages is still evolving. The capability to deliver a multiexpandable interbody cage with a large footprint through a narrow surgical cannula represents a significant advancement in spinal surgery technology. The purpose of this report is to describe a multiexpandable lumbar interbody fusion cage, including implant characteristics, intended use, surgical technique, preclinical testing, and early clinical experience. Results to date suggest that the multiexpandable cage allows a less invasive approach to posterior/transforaminal lumbar interbody fusion surgery by minimizing iatrogenic risks associated with static or vertically expanding interbody prostheses while providing immediate vertebral height restoration, restoration of anatomic alignment, and excellent early-term clinical results. PMID:27729817

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) Submit requests for changes to CAGE files on DD Form 2051, or electronic equivalent, to—Defense Logistics... codes is in Volume 7 of DoD 4100.39-M, Federal Logistics Information System (FLIS) Procedures Manual. ...

  6. Inorganic cage molecules encapsulating Kr: A computational study

    NASA Astrophysics Data System (ADS)

    Chang, Ch.; Patzer, A. B. C.; Sedlmayr, E.; Sülzle, D.

    2005-12-01

    Structural and energetic properties of a series of neutral and charged inorganic cage molecules Kr@Y12@Z20q ( Y=Ni,Pd ; Z=As,Sb,Bi ; q=0,-1,-3 ) where a central krypton atom is encapsulated by two outer cages Y12 and Z20 have been investigated by theoretical density functional techniques (DFT) employing the Becke-Perdew-86 (BP86) gradient corrected exchange correlation functional. The structures are closed shell species representing highly stable local minima of icosahedral point group symmetry Ih . We report energies, equilibrium geometric parameters, selected harmonic vibrational frequencies, and discuss static electric dipole polarizabilities. The overall charge q of these cages seems to be controllable by the nature of the central atom leading to stable configurations when Kr is replaced by Br or As. In this context, we report a stable system where a krypton atom is enclosed by a fullerenelike inorganic double cage.

  7. Evaluation of the pharmacophoric motif of the caged Garcinia xanthones†

    PubMed Central

    Chantarasriwong, Oraphin; Cho, Woo Cheal; Batova, Ayse; Chavasiri, Warinthorn; Moore, Curtis; Rheingold, Arnold L.; Theodorakis, Emmanuel A.

    2010-01-01

    The combination of unique structure and potent bioactivity exhibited by several family members of the caged Garcinia xanthones, led us to evaluate their pharmacophore. We have developed a Pd(0)-catalyzed method for the reverse prenylation of catechols that, together with a Claisen/Diels–Alder reaction cascade, provides rapid and efficient access to various caged analogues. Evaluation of the growth inhibitory activity of these compounds leads to the conclusion that the intact ABC ring system containing the C-ring caged structure is essential to the bioactivity. Studies with cluvenone (7) also showed that these compounds induce apoptosis and exhibit significant cytotoxicity in multidrug-resistant leukemia cells. As such, the caged Garcinia xanthone motif represents a new and potent pharmacophore. PMID:19907779

  8. 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

  9. 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

  10. Synthesis of gem-difluoromethylenated polycyclic cage compounds.

    PubMed

    Masusai, Chonticha; Soorukram, Darunee; Kuhakarn, Chutima; Tuchinda, Patoomratana; Pakawatchai, Chaveng; Saithong, Saowanit; Reutrakul, Vichai; Pohmakotr, Manat

    2015-02-06

    The synthesis of gem-difluoromethylenated polycyclic cage compounds, utilizing PhSCF2SiMe3 as a gem-difluoromethylene building block, is described. The fluoride-catalyzed nucleophilic addition of PhSCF2SiMe3 to both maleic anhydride-cyclopentadiene and maleic anhydride-cyclohexadiene adducts was accomplished with high stereoselectivity to provide the corresponding adducts that were treated with Grignard reagents, followed by acid-catalyzed lactonization to afford the corresponding γ-butyrolactones, each as a single isomer. These γ-butyrolactones underwent intramolecular radical cyclization to give the corresponding tetracyclic cage γ-butyrolactones, which were employed as precursors for the synthesis of gem-difluoromethylenated tetracyclic cage lactols or tetracyclic cage furans, upon treatment with Grignard reagents.

  11. Metal dimer and trimer within spherical carbon cage

    NASA Astrophysics Data System (ADS)

    Kato, Tatsuhisa

    2007-07-01

    C 80 fulleren cage can be used to realize confinement with the highest possible icosahedral ( Ih) symmetry. As examples, La 2@C 80 and Sc 3C 2@C 80 are molecules in which metal dimer and trimer are encapsulated within the C 80 cage. They are recently purified in the substantial amount by using a high performance liquid chromatograph (HPLC), and studied by spectroscopy and X-ray diffraction. The confinement of the metal cluster with the high symmetry ( Ih) cage is reflected in their specific potential of the intra-molecular rotation for the cluster. The result of electron spin resonance (ESR) measurements indicates that the intra-molecular potential is modified by the chemical modification of the C 80 cage as well as by the injection of an excess electron.

  12. Aortic biomechanics by magnetic resonance: early markers of aortic disease in Marfan syndrome regardless of aortic dilatation?

    PubMed

    Teixido-Tura, Gisela; Redheuil, Alban; Rodríguez-Palomares, Jose; Gutiérrez, Laura; Sánchez, Violeta; Forteza, Alberto; Lima, Joao A C; García-Dorado, David; Evangelista, Artur

    2014-01-15

    Previous studies demonstrated the usefulness of MRI in the evaluation of aortic biomechanics in Marfan patients with aortic dilatation. However, these parameters have not been well studied in earlier stages of aortic disease. The present work aimed to study aortic biomechanics: aortic distensibility (AD) and pulse wave velocity (PWV), by MRI in Marfan patients without advanced aortic disease. Eighty consecutive Marfan patients were compared with 36 age- and sex-matched controls. MRI images at the level of ascending, descending and abdominal aorta were used to determine AD and PWV. Marfan patients (27 men; age: 32.0 ± 10.5 years; mean aortic root diameter: 37.2 ± 4.6mm) had lower AD at all levels (ascending 2.6 ± 2.1 vs. 6.2 ± 3.7 mm Hg(-1)·10(-3), p<0.001; descending 3.1 ± 2.0 vs. 8.3 ± 4.2, p<0.001; and abdominal 4.5 ± 2.2 vs. 14.0 ± 5.2, p<0.001), higher aortic arch PWV (8.1 ± 6.5 vs. 4.3 ± 1.8m/s, p<0.01) and ascending-to-abdominal PWV (6.1 ± 3.0 vs. 4.7 ± 1.5m/s, p<0.01) compared with controls. Thirty-five Marfan patients had a non-dilated aortic root (mean aortic root diameter: 34.5 ± 3.8 mm). In multivariable analyses, after adjustment for age, pulse pressure and aortic dimensions, AD remained lower and PWV higher in Marfan patients; even Marfan patients with non-dilated aortic root showed impaired aortic biomechanics compared with controls. Z-score for ascending AD<-3.5 distinguished Marfan patients from controls with 82.5% sensitivity and 86.1% specificity. Aortic biomechanics by MRI were abnormal in the entire aorta in Marfan patients. Moreover, Marfan patients without dilated aortic root showed clear impairment of aortic biomechanics, which suggests that they may be used as early markers of aortic involvement in these patients. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Decreased expression of fibulin-4 in aortic wall of aortic dissection.

    PubMed

    Huawei, P; Qian, C; Chuan, T; Lei, L; Laing, W; Wenlong, X; Wenzhi, L

    2014-02-01

    In this research, we will examine the expression of Fibulin-4 in aortic wall to find out its role in aortic dissection development. The samples of aortic wall were obtained from 10 patients operated for acute ascending aortic dissection and five patients for chronic ascending aortic dissection. Another 15 pieces of samples from patients who had coronary artery bypass were as controls. The aortic samples were stained with aldehyde magenta dyeing to evaluate the arrangement of elastic fibers. The Fibulin-4 protein and mRNA expression were both determined by Western blot and realtime quantitative polymerase chain reaction. Compared with the control group, both in acute and chronic ascending aortic dissection, elastic fiber fragments increased and the expression of fibulin-4 protein significantly decreased (P= 0.045 < 0.05). The level of fibulin-4 mRNA decreased in acute ascending aortic dissection (P= 0.034 < 0.05), while it increased in chronic ascending aortic dissection (P=0.004 < 0.05). The increased amounts of elastic fiber fragments were negatively correlated with the expression of fibulin-4 mRNA in acute ascending aortic dissection. In conclusion, in aortic wall of ascending aortic dissection, the expression of fibulin-4 protein decreased and the expression of fibulin-4 mRNA was abnormal. Fibulin-4 may play an important role in the pathogenesis of aortic dissection.

  14. 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 offer...

  15. 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.

  16. One stage surgical treatment of aortic valve disease and aortic coarctation with aortic bypass grafting through the diaphragm and aortic valve replacement.

    PubMed

    Yu, Zipu; Wu, Shengjun; Li, Chengchen; Zou, Yu; Ma, Liang

    2015-11-10

    To validate ascending aorta-lower abdominal aorta bypass grafting treatment for patients with descending aortic coarctation and an aortic valve disease. The three patients in whom a descending atypical aortic coarctation was associated with an aortic valve disease were treated with one stage surgical treatment with aortic bypass grafting through the diaphragm and aortic valve replacement in our heart center. Operative technique consisted of performing ascending aorta-lower abdominal aorta bypass grafting through diaphragm muscle and implementing aortic valve replacement. The mean time for extracorporeal circulation and occluding clamp of aorta was recorded. Blood pressure data for pre- and post-operation was measured in the limbs. Computer-enhanced transvenous angiograms of pre- and post-operation were applied for detection of aortic stenosis. The other adverse events were noticed in outpatient service during a follow-up period. The mean extracorporeal circulation time was 54 ± 11 min. The mean time for occluding clamp of aorta was 34 ± 6 min. An arterial pressure gradient was totally corrected after surgical treatment. Post-operation computer-enhanced transvenous angiograms showed the grafts to be open with a fluent flow. The patients had no gastrointestinal tract complications. No adverse event was noticed during a follow-up period in outpatient service. Treatment of ascending aorta-lower abdominal aorta bypass is advisable for patients with descending aortic coarctation and an aortic valve disease.

  17. Abdominal aortic aneurysms.

    PubMed

    Lindholt, Jes Sanddal

    2010-12-01

    Although the number of elective operations for abdominal aortic aneurysms (AAA) is increasing, the sex- and age-standardised mortality rate of AAAs continues to rise, especially among men aged 65 years or more. The lethality of ruptured AAA continues to be 80-95%, compared with 5-7% by elective surgery of symptomfree AAA. In order to fulfil all WHO, European, and Danish criteria for screening, a randomised hospitalbased screening trial of 12,639 65-73 year old men in Viborg County (Denmark) was initiated in 1994. It seemed that US screening is a valid, suitable and acceptable method of screening. The acceptance rate was 77%, and 95% accept control scans. Furthermore, persons at the highest risk of having an AAA attend screening more frequently. We found that 97% of the interval cases developed from aortas that initially measured 2.5-2.9 cm - i.e. approx. only 5% attenders need re-screening at 5-year intervals. Two large RCTs have given clear indications of operation. Survivors of surgery enjoy the same quality of life as the background population, and only 2-5% of patients refuse an offer of surgery. Early detection seems relevant since the cardiovascular mortality is more than 4 times higher in AAA patients without previous hospital discharge diagnoses due to cardiovascular disease than among similar men without AAA. The absolute risk difference after 5 years was 16%. So, they will benefit from general cardiovascular preventive action as smoking cessation, statins and low-dose aspirin, which could inhibit further AAA progression. All 4 existing RCTs point in the same direction, viz. in favour of screening of men aged 65 and above. We found that screening significantly reduced AAA-related mortality by 67% within the first five years (NNT = 352). Restriction of screening to men with previous cardiovascular or pulmonary hospital discharge diagnoses would request only 27% of the relevant male population study to be invited, but would only have prevented 46.7% of the

  18. Correction of Spray Concentration and Bioassay Cage Penetration Data

    DTIC Science & Technology

    2012-01-01

    analysis were deployed. Mosquito mortality was monitored using Townzen type bioassay cages (Townzen and Natvig 1973) (16 cm diam 3 4 cm depth; with T-310...into holding cups and mortality counts were made 24 h after treatment. Mosquitoes were considered dead if unresponsive to gentle prodding. Overall insect...Bioassay Cage Penetration Data Author(s): Bradley K. Fritz , W. Clint Hoffmann , Keith Haas , and Jane Bonds Source: Journal of the American Mosquito

  19. A DFT study of dodecahedral beryllium silicide cage clusters

    NASA Astrophysics Data System (ADS)

    Fioressi, Silvina; Bacelo, Daniel E.; Binning, R. C.

    2012-06-01

    Density functional theory calculations have been conducted on 20- and 32-atom dodecahedral and face-capped dodecahedral cage clusters of beryllium and silicon. Stable Be24Si8, Be12Si8 and Be12Si20 cages are described, as is a stuffed cluster consisting of dodecahedral Si20 with an endohedral icosahedral Be12. Especial stability is associated with clusters in which faces are capped by silicon atoms, acting as electron donors to beryllium atoms.

  20. Moderate aortic enlargement and bicuspid aortic valve are associated with aortic dissection in Turner syndrome: report of the international turner syndrome aortic dissection registry.

    PubMed

    Carlson, Misty; Airhart, Nathan; Lopez, Leo; Silberbach, Michael

    2012-10-30

    Girls and women with Turner syndrome are at risk for aortic dissection and rupture. However, the size of the aorta and the clinical characteristics among those with Turner syndrome and dissection have received little attention. We obtained medical records from 20 individuals who voluntarily participated in the International Turner Syndrome Aortic Dissection Registry. Type A dissections occurred in 17 of 20 (85%) cases, and type B occurred in 3 cases of which 1 occurred after coarctation stent placement. Of those with spontaneous aortic dissections, 18 of 19 (95%) had an associated cardiac malformation that included a bicuspid aortic valve. In 1 individual there was no predisposing finding other than the presence of Turner syndrome. Associated pregnancy was documented in 1 of 19 (5%). More than half (13/19, 68%) came to medical attention >24 hours after the onset of symptoms. For those with type A dissections, the mean ascending aortic size index was 2.7±0.6 cm/m(2) (n=9). Aortic dissection in Turner syndrome occurs in young individuals at smaller aortic diameters than in the general population or other forms of genetically triggered aortopathy. The absence of aortic valve or other cardiac malformations appears to markedly reduce the risk of aortic dissection However, aortic dissection can occur in Turner syndrome without cardiac malformations or hypertension. Individuals with Turner syndrome who are >18 years of age with an ascending aortic size index >2.5 cm/m(2) should be considered for an aortic operation to prevent aortic dissection.

  1. A shift in designing cage-washing operations.

    PubMed

    Zynda, Jeffrey R

    2015-04-01

    Support systems for animal research facilities are often complex and resource-intensive operations whose successful design and implementation require substantial experience. The cage-washing center is at the heart of these support spaces and is not only one of the largest spaces found in an animal facility but also one of the greatest consumers of resources, in terms of both utilities and human labor. Certain methodologies and systems for cage-wash operations have become 'go-to' solutions, but alternative approaches have the potential to reduce utility consumption and human labor. The author's firm analyzed cage-washing operations at an academic institution with the goal of reducing consumption of resources, both human labor and utilities such as water, steam and electricity. Here he describes the analysis and design process as a case study and shows that substantial savings can be achieved by using alternative systems in cage-washing systems. He recommends that cage-washing operations can be optimized by thoroughly investigating the anticipated cage-washing throughput and then thoughtfully selecting the most efficient means to handle that workload.

  2. Folding Dynamics and Pathways of the Trp-Cage Miniproteins

    PubMed Central

    2015-01-01

    Using alternate measures of fold stability for a wide variety of Trp-cage mutants has raised the possibility that prior dynamics T-jump measures may not be reporting on complete cage formation for some species. NMR relaxation studies using probes that only achieve large chemical shift difference from unfolded values on complete cage formation indicate slower folding in some but not all cases. Fourteen species have been examined, with cage formation time constants (1/kF) ranging from 0.9–7.5 μs at 300 K. The present study does not change the status of the Trp-cage as a fast folding, essentially two-state system, although it does alter the stage at which this description applies. A diversity of prestructuring events, depending on the specific analogue examined, may appear in the folding scenario, but in all cases, formation of the N-terminal helix is complete either at or before the cage-formation transition state. In contrast, the fold-stabilizing H-bonding interactions of the buried Ser14 side chain and the Arg/Asp salt bridge are post-transition state features on the folding pathway. The study has also found instances in which a [P12W] mutation is fold destabilizing but still serves to accelerate the folding process. PMID:25184759

  3. 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

  4. Homogenized boundary conditions and resonance effects in Faraday cages.

    PubMed

    Hewett, D P; Hewitt, I J

    2016-05-01

    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.

  5. Rat Breeding Parameters According to Floor Space Available in Cage.

    PubMed

    Allen, Kenneth P; Dwinell, Melinda R; Zappa, Allison M; Michaels, Andrea M; Murray, Kathleen M; Thulin, Joseph D

    2016-01-01

    The cage floor space recommended for a female rat with a litter is greater in the 8th edition of the Guide for the Care and Use of Laboratory Animals than in previous editions. As a result, research institutions using commonly available cages to house rats may not offer the recommended amount of space for a breeding pair and litter housed in the same cage. We evaluated breeding parameters in rats housed in cages with 143 in(2) (922.6 cm(2)) compared with 210 in(2) (1355 cm(2)) of floor space. Given the strains of rats typically used at our institution, a monogamous breeding pair and litter requires 164 in(2) (1058.1 cm(2)) of floor space according to the Guide. Pairs of breeding animals were housed in each type of cage; and average time between litters, number of litters born, percentage of litter weaned, numbers of pups born and weaned, and average weaning weights were evaluated. None of the breeding parameters evaluated differed according to the floor space of the cage in which the rats were housed.

  6. 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. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

  7. Electrostatic assembly of binary nanoparticle superlattices using protein cages.

    PubMed

    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 AB(8)(fcc) 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.

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

    PubMed Central

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

    2009-01-01

    Originally designed to block the prenylation of oncogenic Ras, inhibitors of protein farnesyltransferase currently in pre-clinical 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 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 analogues towards a variety of in vitro and in vivo applications. PMID:18844669

  9. 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.

  10. 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.

  11. Homogenized boundary conditions and resonance effects in Faraday cages

    NASA Astrophysics Data System (ADS)

    Hewett, D. P.; Hewitt, I. J.

    2016-05-01

    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.

  12. Measurement of effective aortic valve area using three-dimensional echocardiography in children undergoing aortic balloon valvuloplasty for aortic stenosis.

    PubMed

    Bharucha, Tara; Fernandes, Fernanda; Slorach, Cameron; Mertens, Luc; Friedberg, Mark Kevin

    2012-04-01

    Pressure gradient is used for timing of balloon aortic valvuloplasty for aortic stenosis (AS) in children, but does not correlate well with outcome and is limited if ventricular function is poor. In adults, effective orifice area (EOA) is used to assess AS severity, but EOA by continuity equation or 2D echo is unreliable in children. Three-dimensional echocardiography (3DE) may reliably assess EOA but has not been studied in children. We assessed measurement of aortic valve EOA by 3DE in children with AS before and after balloon aortic valvuloplasty and compared results with change in aortic valve gradient. 3DE was performed at time of catheterization before and after balloon aortic valvuloplasty. Using 3DE multiplanar review mode, valve annulus diameter, area, and EOA were measured and compared with change in aortic gradient and degree of aortic insufficiency. Twenty-four 3DE studies in 12 children (mean age 4.4 ± 5.0 years) were analyzed. EOA was measurable in all. Catheter peak gradient decreased from 45 ± 10 to 26 ± 17 mmHg (P = 0.0018). 3DE EOA increased after balloon aortic valvuloplasty (0.59 ± 0.52 cm(2) vs 0.80 ± 0.70 cm(2) ; P = 0.03), without change in valve diameter. EOA change correlated with change in peak (r = 0.77; P = 0.005) and mean (r = 0.60; P = 0.03) aortic valve gradient post balloon aortic valvuloplasty. 3DE facilitates EOA measurement in pediatric AS and correlates with change in aortic valve gradient after balloon valvuloplasty. © 2011, Wiley Periodicals, Inc.

  13. [Surgical technique of aortic valve replacement for small aortic annulus in elderly patients].

    PubMed

    Hata, T; Fujiwara, K; Furukawa, H; Tsushima, Y; Yoshitaka, H; Kuinose, M; Minami, H; Ishida, A; Tamura, K; Totsugawa, T; Kanemitsu, H; Ozawa, M

    2006-04-01

    Recent reports have shown that aortic valve replacement in elderly patients over 65 years with atherosclerotic aortic stenosis and a small aortic annulus is possible by using a small sized bioprosthesis (Carpentier-Edwards pericardial valve). Here we present out surgical technique. Firstly, the native calcified aortic valve was removed completely to gain total exposure of the surrounding aortic root and sinus of Valsalva like Bentall procedure. Secondly, a small sized bioprosthesis was implanted with intermittent noneverting mattress 2-0 sutures with spaghetti and small polytetrafluoroethylene (PTFE) felt. Aortic annulus is the dilated by inserting Hegar dilator sizing from 25 to 27 mm. Therefore, aortic valve replacement for small aortic annulus in intra- or supra-annular position should be easily accomplished. Good surgical results and hemodynamic state were achieved in 25 consecutive cases using this technique.

  14. Hypertensive Emergency in Aortic Dissection and Thoracic Aortic Aneurysm—A Review of Management

    PubMed Central

    Gupta, Prateek K.; Gupta, Himani; Khoynezhad, Ali

    2009-01-01

    Over the last few decades, treatment for aortic dissection and thoracic aortic aneurysms has evolved significantly with improvement in outcomes. Treatment paradigms include medical, endovascular and surgical options. As aortic dissection presents as a hypertensive emergency, diligent control of BP is of utmost importance in order to reduce the progression of dissection with possible aortic branch malperfusion. Treatment should begin on arrival to the emergency department and continues in the intensive care unit, endovascular suite or the operating room. Novel antihypertensive medications with improved pharmacological profile and improved surgical techniques, have improved the prognosis of patients with aortic aneurysm and/or aortic dissection. Nevertheless, morbidity and mortality remain high and hypertensive emergency poses a significant challenge in aortic dissection and thoracic aortic aneurysms. PMID:27713224

  15. The Relationship between Tension and Length of the Aortic Adventitia Resected from the Aortic Wall of Acute Aortic Dissection

    PubMed Central

    Kitano, Mitsuru; Teranishi, Hiroo; Kudo, Masahumi; Matsuura, Makoto

    2014-01-01

    Objective: To our knowledge, no previous study has described the measurement of the tensile strength of the human aortic adventitia. In the present study, we examined the relationship between the tension and length of the aortic adventitia resected from the aortic wall of patients with acute aortic dissection. Methods: We obtained rectangular specimens from the aortic adventitia that was resected in patients with acute aortic dissection during surgery. The specimens were placed on a tension meter (Digital Force Gauge FGS-10, SHIMPO, Kyoto, Japan) within 15 min after resection and stretched until they were pulled apart, and the tension and length were recorded. Results: We obtained 18 specimens during surgery from 11 cases of acute aortic dissection. When the specimen was being pulled apart, the mean tension recorded was 10.2 ± 4.9 N/cm specimen width, whereas the mean elongated length recorded was 4.2 ± 1.1 mm/cm specimen length. Discussion: We determined that the aortic adventitia is elastic and expandable up to 140% of its original length. This indicates that dilation of the aorta to >4.2 cm in diameter may result in a rupture if the original aortic diameter prior to dissection was 3 cm. (*English translation of J Jpn Coll Angiol 2013; 53: 77-81) PMID:25298826

  16. Subsidence of polyetheretherketone cage after minimally invasive transforaminal lumbar interbody fusion.

    PubMed

    Kim, Moon-Chan; Chung, Hung-Tae; Cho, Jae-Lim; Kim, Dong-Jun; Chung, Nam-Su

    2013-04-01

    A retrospective case series. The aim of this study was to determine the rate of cage subsidence after minimally invasive transforaminal lumbar interbody fusion (MITLIF) conducted using a polyetheretherketone (PEEK) cage, and to identify associated risk factors. Although various rates of cage subsidence after lumbar interbody fusion have been reported, few studies have addressed subsidence rate after MITLIF using PEEK cage. A total of 104 consecutive patients who had undergone MITLIF using a PEEK cage with a minimum follow-up of 2 years were included in this study. Cage subsidence was defined to have occurred when a cage was observed to sink into an adjacent vertebral body by ≥2 mm on the postoperative or serial follow-up lateral radiographs. The demographic variables considered to affect cage subsidence were the following: age, sex, body mass index, bone mineral density, diagnosis, number of fusion segment, and the quality/quantity of back muscle, and the cage-related variables considered were: level of fusion, intervertebral angle, cage size, cage position, and postoperative distraction of disc height. Logistic regression analysis was conducted to explore relations between these variables and cage subsidence. : For the 122 cages inserted, the rate of cage subsidence was 14.8% (18 cages), and cage subsidence occurred within 7.2±8.5 (1-25) months of surgery. The odds ratios for factors found to significantly increase the risk of cage subsidence were; 1.950 (95% confidence interval, 1.002-4.224) for L5-S1 level, and 1.018 (95% confidence interval, 1.000-1.066) for anterior cage position. The rate of PEEK cage subsidence after MITLIF was relatively low. End-plate manipulation and cage insertion during MITLIF were not influenced by a small operation window.

  17. Frequency distribution of axon diameters in the left aortic nerve of the rat raised in space--Neurolab Program.

    PubMed

    Yamasaki, M; Shimizu, T; Miyake, M; Miyamoto, Y; Waki, H; Katsuda, S I; O-ishi, H; Nagayama, T; Katahira, K; Wago, H; Okoch, T; Kaneko, M; Matsumoto, S; Nagaoka, S; Mukai, C

    1999-09-01

    To study development of the aortic baroreflex mechanisms under conditions of microgravity, we carried out the various experiments in the neonate rats aged 25 days raised in microgravity for 16 days (flight: FLT group) in Neurolab program (STS-90, space shuttle Columbia, launch date: Apr 17, '98. Some results of the experiments were already reported. The results of histological examination of the aortic nerve which is the afferent of the aortic baroreflex showed that the number of unmyelinated fibers in FLT was significantly less in than those in two control groups and there was no difference between FLT and each control group in the analysis of myelin. In the present paper, the frequency distribution of axon diameters of the left aortic nerves in FLT was compared to that in two ground control groups to examine the growth of the aortic nerve fibers in space. After breeding Sprague-Dawley rats for 16 days in the shuttle in space and in the animal center in the Kennedy space center, a total of 43 deeply anesthetized rats were perfused with 1% parahormaldehyde and 1% glutaraldehyde or 4% parahormaldehyde solution buffered at pH7.4 with 0.12 M phosphate solution. Concerning the control groups, one group was the asynchronous ground control (AGC) group in which the rats were housed in the same cages as those on the shuttle, and the other was the vivarium ground control (VIV) group in which the rats were housed in commercial cages. The cervical region of the left aortic nerve which is a branch of the vagus was cut off and stored in the same fixative as that used for perfusion, and postfixed in the solution of 1% OsO4, for 2 hours within 24 hours after the perfusion. The fixed specimens were embedded in epoxy resin blocks by the usual method for electron microscopy following dehydration. Electron microscopic montages of transverse sections of these nerve trunks were made from the five left aortic nerves in each group. The magnification of the montages was approximately

  18. Multicomponent Protein Cage Architectures for Photocatalysis

    SciTech Connect

    Gupta, Arunava; Prevelige, Peter E

    2016-01-04

    The primary goal of the project was to develop protein-templated approaches for the synthesis and directed assembly of semiconductor nanomaterials that are efficient for visible light absorption and hydrogen production. In general, visible-light-driven photocatalysis reactions exhibit low quantum efficiency for solar energy conversion primarily because of materials-related issues and limitations, such as the control of the band gap, band structure, photochemical stability, and available reactive surface area of the photocatalyst. Synthesis of multicomponent hierarchical nano-architectures, consisting of semiconductor nanoparticles (NPs) with desired optical properties fabricated to maximize spatial proximity for optimum electron and energy transfer represents an attractive route for addressing the problem. Virus capsids are highly symmetrical, self-assembling protein cage nanoparticles that exist in a range of sizes and symmetries. Selective deposition of inorganic, by design, at specific locations on virus capsids affords precise control over the size, spacing, and assembly of nanomaterials, resulting in uniform and reproducible nano-architectures. We utilized the self-assembling capabilities of the 420 subunit, 60 nm icosahedral, P22 virus capsid to direct the nucleation, growth, and proximity of a range of component materials. Controlled fabrication on the exterior of the temperature stable shell was achieved by genetically encoding specific binding peptides into an externally exposed loop which is displayed on each of the 420 coat protein subunits. Localization of complimentary materials to the interior of the particle was achieved through the use “scaffolding-fusion proteins. The scaffolding domain drives coat protein polymerization resulting in a coat protein shell surrounding a core of approximately 300 scaffolding/fusion molecules. The fusion domain comprises a peptide which specifically binds the semiconductor material of interest.

  19. A Webb in a Golden Cage

    NASA Image and Video Library

    2017-09-27

    This photograph shows support structures wrapped in gold thermal blankets that look like a golden cage. The structure is housed within the vacuum chamber called the Space Environment Simulator, or SES. The SES is located at NASA's Goddard Space Flight Center in Greenbelt, Md., where components of the James Webb Space Telescope are being tested to withstand the extreme temperatures of space. The entire structure is a system of supports and thermal control devices for the series of thermal tests. Visible in the photo is the lower GESHA (Ground Environmental SES Hardware Assembly).The box in the center photo is a group of four LN2 (liquid nitrogen) panels that are designed to keep it at around 100 kelvins. The panels surround the primary mirror of the OTE (Optical Telescope Element) Simulator or OSIM. When NASA's Webb telescope launches in 2018, it will fly a million miles from Earth and enable scientists on Earth to see the most detailed pictures of the universe. For another photo of the SES, visit: www.nasa.gov/topics/technology/features/webb_osim.html For more information about NASA's James Webb Space Telescope, visit: www.jwst.nasa.gov Photo: NASA/Chris Gunn Text: NASA/Rob Gutro NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  20. Severe Aortic Stenosis Associated with Unicommissural Unicuspid Aortic Valve in a Middle Aged Male

    PubMed Central

    Kwon, Hee-Jin; Kim, Song Soo; Sun, Byung Joo; Jin, Sun Ah; Kim, Jun-Hyung; Lee, Jae-Hwan; Choi, Siwan; Jeong, Jin-Ok; Seong, In-Whan

    2016-01-01

    Unicuspid aortic valve (UAV) is an extremely rare form of congenital aortic valvular abnormality. Although UAV shows similar clinical characteristics to bicuspid aortic valve, the clinical symptoms develop at earlier age and progress at a faster pace in UAV. In this report, we are presenting a 42-year-old male with severe aortic stenosis associated with unicommissural UAV. The patients underwent a successful Bentall operation. PMID:27721957

  1. Aortic Stenosis: Pathophysiology, Diagnosis, and Therapy.

    PubMed

    Joseph, Jessica; Naqvi, Syed Yaseen; Giri, Jay; Goldberg, Sheldon

    2017-03-01

    The incidence of aortic stenosis increases with age, affecting up to 10% of the population by the eighth decade. Once symptoms develop, aortic stenosis is rapidly fatal. Proper management requires an understanding of the physiology and criteria used to define disease severity. There is no effective pharmacologic treatment. Surgical aortic valve replacement has been the gold standard treatment for decades. However, over the last 10 years transcatheter aortic valve replacement has emerged as an attractive, less-invasive option for appropriately selected patients. Refinements in valve design and delivery systems have led to widespread use of this breakthrough technology in selected patients. We review the pathophysiology, criteria for valve replacement, and the results of the trials comparing transcatheter aortic valve replacement with surgical aortic valve replacement.

  2. Automated home cage observations as a tool to measure the effects of wheel running on cage floor locomotion.

    PubMed

    de Visser, Leonie; van den Bos, Ruud; Spruijt, Berry M

    2005-05-28

    This paper introduces automated observations in a modular home cage system as a tool to measure the effects of wheel running on the time distribution and daily organization of cage floor locomotor activity in female C57BL/6 mice. Mice (n = 16) were placed in the home cage system for 6 consecutive days. Fifty percent of the subjects had free access to a running wheel that was integrated in the home cage. Overall activity levels in terms of duration of movement were increased by wheel running, while time spent inside a sheltering box was decreased. Wheel running affected the hourly pattern of movement during the animals' active period of the day. Mice without a running wheel, in contrast to mice with a running wheel, showed a clear differentiation between novelty-induced and baseline levels of locomotion as reflected by a decrease after the first day of introduction to the home cage. The results are discussed in the light of the use of running wheels as a tool to measure general activity and as an object for environmental enrichment. Furthermore, the possibilities of using automated home cage observations for e.g. behavioural phenotyping are discussed.

  3. Aortic and mitral valve replacement with cloth-covered Braunwald-Cutter prosthesis. A three-year follow-up.

    PubMed

    Pluth, J R; Broadbent, J C; Barnhorst, D A; Danielson, G K

    1975-09-01

    From February, 1971, through February, 1974, heart valves of 510 patients were replaced with cloth-covered Braunwald-Cutter prostheses. The data indicate that cloth encapsulation of the prosthetic cage is associated with a reduction in thromboembolic complications, particularly for mitral valves. Cloth wear on the distal strut, however, is not prevented by use of a Silastic poppet and appears to be a typical finding in aortic valves recovered or inspected after 3 months. Excessive poppet wear has also been noted in the aortic position; poppet embolization has occurred on 2 occasions, and a third patient was found, at the time of reoperation for periprosthetic leak, to have opppet wear sufficient to permit embolization. Although there have been no reports of clinical malfunction of the mitral prosthesis at the time of this writing, further long-term observation of these patients appears warranted.

  4. Aortic root vasculitis associated with Cogan's syndrome.

    PubMed

    Gasparovic, Hrvoje; Djuric, Zeljko; Bosnic, Dubravka; Petricevic, Mate; Brida, Margita; Dotlic, Snjezana; Biocina, Bojan

    2011-07-01

    Cogan's syndrome is characterized by nonsyphilitic interstitial keratitis and an audiovestibular disorder resembling Meniere disease. We report a patient with progressive congestive heart failure due to massive aortic and mitral insufficiency coupled with aortitis leading to an ascending aortic aneurysm. The patient underwent successful aortic root replacement and mitral valve repair. Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Traumatic aortic incompetence following road traffic accident

    PubMed Central

    Irving, J. B.

    1974-01-01

    This case report describes the presentation and treatment of a case of aortic incompetence, resulting from a road traffic accident. The relevant literature is briefly reviewed. Aortic incompetence due to trauma has been described following non-penetrating chest injuries, such as kicks from horses (Barie, 1881), falls from heights and crushing accidents (Kissane, Koons and Clark, 1948; Levine, Roberts and Morrow, 1962). Despite the frequency of road traffic accidents, there have been no recent reports of traumatic aortic valve damage. PMID:4467876

  6. Association Between Gout and Aortic Stenosis.

    PubMed

    Chang, Kevin; Yokose, Chio; Tenner, Craig; Oh, Cheongeun; Donnino, Robert; Choy-Shan, Alana; Pike, Virginia C; Shah, Binita D; Lorin, Jeffrey D; Krasnokutsky, Svetlana; Sedlis, Steven P; Pillinger, Michael H

    2017-02-01

    An independent association between gout and coronary artery disease is well established. The relationship between gout and valvular heart disease, however, is unclear. The aim of this study was to assess the association between gout and aortic stenosis. We performed a retrospective case-control study. Aortic stenosis cases were identified through a review of outpatient transthoracic echocardiography (TTE) reports. Age-matched controls were randomly selected from patients who had undergone TTE and did not have aortic stenosis. Charts were reviewed to identify diagnoses of gout and the earliest dates of gout and aortic stenosis diagnosis. Among 1085 patients who underwent TTE, 112 aortic stenosis cases were identified. Cases and nonaortic stenosis controls (n = 224) were similar in age and cardiovascular comorbidities. A history of gout was present in 21.4% (n = 24) of aortic stenosis subjects compared with 12.5% (n = 28) of controls (unadjusted odds ratio 1.90, 95% confidence interval 1.05-3.48, P = .038). Multivariate analysis retained significance only for gout (adjusted odds ratio 2.08, 95% confidence interval 1.00-4.32, P = .049). Among subjects with aortic stenosis and gout, gout diagnosis preceded aortic stenosis diagnosis by 5.8 ± 1.6 years. The age at onset of aortic stenosis was similar among patients with and without gout (78.7 ± 1.8 vs 75.8 ± 1.0 years old, P = .16). Aortic stenosis patients had a markedly higher prevalence of precedent gout than age-matched controls. Whether gout is a marker of, or a risk factor for, the development of aortic stenosis remains uncertain. Studies investigating the potential role of gout in the pathophysiology of aortic stenosis are warranted and could have therapeutic implications. Published by Elsevier Inc.

  7. Transcatheter aortic valve replacement for bicuspid aortic stenosis 13years post heart transplant.

    PubMed

    Julien, Maureen B; Desai, Nimesh; Brozena, Susan; Herrmann, Howard C

    2016-12-16

    Despite the widespread use of transcatheter aortic valve replacement (TAVR) for moderate and high-risk patients with severe aortic stenosis, it is utilized less frequently in patients with bicuspid aortic valves (BAV). Orthotopic heart transplant (OHT) donors tend to be younger and may have undiagnosed BAV. We present a case of successful TAVR in a patient with BAV thirteen years after OHT.

  8. Outcomes of contemporary use of rectangular titanium stand-alone cages in anterior cervical discectomy and fusion: cage subsidence and cervical alignment.

    PubMed

    Yamagata, Toru; Takami, Toshihiro; Uda, Takehiro; Ikeda, Hidetoshi; Nagata, Takashi; Sakamoto, Shinichi; Tsuyuguchi, Naohiro; Ohata, Kenji

    2012-12-01

    Cervical intervertebral disc replacement using a rectangular titanium stand-alone cage has become a standard procedure for anterior cervical discectomy and fusion (ACDF). We examined outcomes resulting from the contemporary use of rectangular titanium stand-alone cages for ACDF, particularly focusing on cage subsidence and subsequent kyphotic malalignment. Patient data were collected prospectively, and a total of 47 consecutive patients who underwent periodic follow-up of at least 1 year's duration after ACDF were studied retrospectively. Sixty-three rectangular titanium cages were implanted during 31 1-level and 16 2-level procedures. None of the patients developed surgery-related complications (including cage displacement or extrusion). Mean Neurosurgical Cervical Spine Scale scores were significantly improved at 1 year after surgery. Twelve of the 63 inserted cages (19.0%) were found to have cage subsidence, occurring in 11 of 47 patients (23.4%). There was no significant difference in functional recovery between patients with and without cage subsidence. Logistic regression analysis indicated that fusion level, cage size and cage position were significantly related to cage subsidence. The distraction ratio among patients with cage subsidence was significantly higher than that among patients without cage subsidence. Cage subsidence resulted in early deterioration of local angle and total alignment of the cervical spine. Although a longer follow-up is warranted, a good surgical outcome with negligible complications appears to justify the use of rectangular titanium stand-alone cages in 1- and 2-level ACDF. Excessive distraction at the fusion level should be avoided, and cage position should be adjusted to the anterior vertical line. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Low-gradient aortic stenosis.

    PubMed

    Clavel, Marie-Annick; Magne, Julien; Pibarot, Philippe

    2016-09-07

    An important proportion of patients with aortic stenosis (AS) have a 'low-gradient' AS, i.e. a small aortic valve area (AVA <1.0 cm(2)) consistent with severe AS but a low mean transvalvular gradient (<40 mmHg) consistent with non-severe AS. The management of this subset of patients is particularly challenging because the AVA-gradient discrepancy raises uncertainty about the actual stenosis severity and thus about the indication for aortic valve replacement (AVR) if the patient has symptoms and/or left ventricular (LV) systolic dysfunction. The most frequent cause of low-gradient (LG) AS is the presence of a low LV outflow state, which may occur with reduced left ventricular ejection fraction (LVEF), i.e. classical low-flow, low-gradient (LF-LG), or preserved LVEF, i.e. paradoxical LF-LG. Furthermore, a substantial proportion of patients with AS may have a normal-flow, low-gradient (NF-LG) AS: i.e. a small AVA-low-gradient combination but with a normal flow. One of the most important clinical challenges in these three categories of patients with LG AS (classical LF-LG, paradoxical LF-LG, and NF-LG) is to differentiate a true-severe AS that generally benefits from AVR vs. a pseudo-severe AS that should be managed conservatively. A low-dose dobutamine stress echocardiography may be used for this purpose in patients with classical LF-LG AS, whereas aortic valve calcium scoring by multi-detector computed tomography is the preferred modality in those with paradoxical LF-LG or NF-LG AS. Although patients with LF-LG severe AS have worse outcomes than those with high-gradient AS following AVR, they nonetheless display an important survival benefit with this intervention. Some studies suggest that transcatheter AVR may be superior to surgical AVR in patients with LF-LG AS.

  10. Aortic root dilatation in young men with normally functioning bicuspid aortic valves

    PubMed Central

    Nistri, S; Sorbo, M; Marin, M; Palisi, M; Scognamiglio, R; Thiene, G

    1999-01-01

    OBJECTIVE—To evaluate the dimensions of the aortic root in a selected population of young males with isolated normally functioning bicuspid aortic valve.
DESIGN AND SETTING—Echocardiographic and Doppler evaluation of conscripts with bicuspid aortic valve at the time of military pre-enrolment screening in two military hospitals.
SUBJECTS AND METHODS—66 consecutive young men with a normally functioning bicuspid aortic valve were studied to assess aortic size at four aortic levels: annulus, sinuses of Valsalva, supra-aortic ridge, and proximal ascending aorta; 70 consecutive normal young subjects, matched for age and body surface area, were used as controls.
RESULTS—In men with a bicuspid aortic valve, the diameter of the aortic root was significantly larger than in controls at the sinuses (3.16 (0.37) v 2.87 (0.31) cm, p < 0.001), at the supra-aortic ridge (2.64 (0.46) v 2.47 (0.28) cm, p = 0.01), and at the level of the proximal ascending aorta (3.12 (0.48) v 2.69 (0.28) cm, p < 0.001). The prevalence of aortic root dilatation was 7.5% at the annulus (5/66), 19.6% at the sinuses (13/66), 15% at the supra-aortic ridge (10/66), and 43.9% at the ascending aorta (29/66); 32 subjects (48%) had aortic root dimensions comparable with controls, while 34 (52%) had definitely abnormal aortic root dimensions.
CONCLUSIONS—Aortic root enlargement in people with a bicuspid aortic valve occurs independently of haemodynamic abnormalities, age, and body size. However, there appear to be different subgroups of young adults with bicuspid aortic valves, one of which is characterised by aortic dilatation, possibly caused by a congenital abnormality of the aortic wall.


Keywords: bicuspid aortic valve; aortic root dilatation PMID:10377302

  11. Aortic dilatation in children with systemic hypertension.

    PubMed

    Gupta-Malhotra, Monesha; Devereux, Richard B; Dave, Archana; Bell, Cynthia; Portman, Ronald; Milewicz, Diana

    2014-04-01

    The aim of the study was to determine the presence of aortic dilatation in hypertensive children, the prevalence of which is 4% to 10% in hypertensive adults. Prospectively enrolled multiethnic children, untreated for their hypertension, underwent an echocardiogram to exclude congenital heart disease and evaluate for end-organ damage and aortic size. The aorta was measured in the parasternal long-axis view at three levels: the sinus of Valsalva, supra-tubular junction, and the ascending aorta. Aortic dilatation was determined by z-score >2 at any one of the levels measured. Hypertension was defined as blood pressure above the 95th percentile based on the Fourth Working Group criteria confirmed by 24-hour ambulatory blood pressure monitoring. Among 142 consecutive hypertensive children (median age, 14 years; 45% females) aortic dilatation was detected in 2.8% (95% confidence interval, 1%-7%; median age, 16 years; 100% females). Children with aortic dilatation, when compared with those without, had significantly more aortic valve insufficiency (P = .005) and left ventricular hypertrophy (P = .018). Prevalence of aortic dilatation was 2.8% and was associated with significantly more aortic insufficiency and left ventricular hypertrophy in comparison to those without aortic dilatation.

  12. Aortic Dilatation in Children with Systemic Hypertension

    PubMed Central

    Gupta-Malhotra, Monesha; Devereux, Richard B.; Dave, Archana; Bell, Cynthia; Portman, Ronald; Milewicz, Diana

    2014-01-01

    Background The aim of the study was to determine presence of aortic dilatation in hypertensive children, the prevalence of which is 4–10% in hypertensive adults. Methods Prospectively enrolled multiethnic children untreated for their hypertension, underwent an echocardiogram to exclude congenital heart disease and evaluate for end-organ damage and aortic size. The aorta was measured in the parasternal long-axis view at 3 levels: the sinus of Valsalva, supra-tubular junction and the ascending aorta. Aortic dilatation was determined by z-score > 2 at any 1 of the levels measured. Hypertension was defined as blood pressure above the 95th percentile based on the Fourth Working Group criteria confirmed by 24-hour ambulatory blood pressure monitoring. Results Among 142 consecutive hypertensive children (median age 14 years, 45% females) aortic dilatation was detected in 2.8% (95% CI 1% to 7%, median age 16 years, 100% females). Children with aortic dilatation, when compared to those without, had significantly more aortic valve insufficiency (p = 0.005) and left ventricular hypertrophy (p = 0.018). Conclusions Prevalence of aortic dilatation was 2.8% and was associated with significantly more aortic insufficiency and left ventricular hypertrophy in comparison to those without aortic dilatation. PMID:24507486

  13. [Surgery of aortic dissection: for which patient?].

    PubMed

    Verhoye, Jean-Philippe; Abouliatim, Issam; Larralde, Antoine; Beneux, Xavier; Heautot, Jean-François

    2011-01-01

    In the acute stage (less than two weeks), surgery is indicated for Stanford type A aortic dissections. With respect to the initial work-up, surgery consists in replacing the ascending aorta, sometimes the aortic arch (with supra aortic vessels reimplantation), and aortic valve replacement (valve replacement, Bentall valved tube or valve sparing Tyron David technique). Ischemic visceral complications must be searched for and treated by endovascular techniques or surgery. Aneurismal evolution of chronic dissections must be treated surgically. Replacement can encompass the entire aorta. Copyright © 2010. Published by Elsevier Masson SAS.

  14. 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

  15. Bacillus licheniformis prosthetic aortic valve endocarditis.

    PubMed Central

    Santini, F; Borghetti, V; Amalfitano, G; Mazzucco, A

    1995-01-01

    A 73-year old man developed an acute prosthetic aortic valve dehiscence for which emergent operation was undertaken. The intraoperative evidence of an aortic annular disruption and of a subannular abscess led to the hypothesis that an endocarditis process was involved. The aortic valve was replaced with a stentless porcine bioprosthesis. Cultures taken intraoperatively from the aortic area had a pure growth of aerobic, spore-forming, gram-positive bacilli identified as Bacillus licheniformis. The patient responded to specific antibiotic therapy with no relapse at a 20-month follow-up. The potentiality of B. licheniformis as a pathogen should be reconsidered. PMID:8576381

  16. Hypoplasia of the aortic root 1

    PubMed Central

    Nicks, Rowan; Cartmill, T.; Bernstein, L.

    1970-01-01

    We report a technique for the enlargement of a hypoplastic aortic root by an operation whereby the hypoplastic aortic root has been so enlarged by the insertion of a Dacron fabric gusset that it will accommodate a size 9A or larger Starr-Edwards prosthesis. Our experience in five patients is described. No matter what type of valve is used for replacement of a diseased aortic valve, and no matter what improved designs of valvular prosthesis are ultimately developed, it will be necessary (in the particular group described) to enlarge the aortic ring to accommodate a size which will function correctly without causing left ventricular outflow obstruction. Images PMID:5452289

  17. Aortic Stenosis: Changing Disease Concepts

    PubMed Central

    Rashedi, Nina

    2015-01-01

    Aortic stenosis (AS) occurs in almost 10% of adults over age 80 years with a mortality about 50% at 2 years unless outflow obstruction is relieved by aortic valve replacement (AVR). Development of AS is associated with anatomic, clinical and genetic risk factors including a bicuspid valve in 50%; clinical factors that include older age, hypertension, smoking, diabetes and elevated serum lipoprotein(a) [Lp(a)] levels; and genetic factors such as a polymorphism in the Lp(a) locus. Early stages of AS are characterized by focal areas of leaflet thickening and calcification. The rate of hemodynamic progression is variable but eventual severe AS is inevitable once even mild valve obstruction is present. There is no specific medical therapy to prevent leaflet calcification. Basic principles of medical therapy for asymptomatic AS are patient education, periodic echocardiographic and clinical monitoring, standard cardiac risk factor evaluation and modification and treatment of hypertension or other comorbid conditions. When severe AS is present, a careful evaluation for symptoms is needed, often with an exercise test to document symptom status and cardiac reserve. In symptomatic patients with severe AS, AVR improves survival and relieves symptoms. In asymptomatic patients with severe AS, AVR also is appropriate if ejection fraction is < 50%, disease progression is rapid or AS is very severe (aortic velocity > 5 m/s). The choice of surgical or transcatheter AVR depends on the estimated surgical risk plus other factors such as frailty, other organ system disease and procedural specific impediments. PMID:26140146

  18. Cocking of a poppet-disc prosthesis in the aortic position. A cause of intermittent aortic regurgitation.

    PubMed

    Hammer, W J; Hearne, M J; Roberts, W C

    1976-02-01

    Intermittent aortic regurgitation due to cocking is described for the first time after replacement of the aortic valve with a poppet-disc prosthesis. A combination of disc grooving and strut thrombus produced the cocking with resultant aortic regurgitation.

  19. 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

  20. The concept of aortic replacement based on computational fluid dynamic analysis: patient-directed aortic replacement†

    PubMed Central

    Heim, Laurant; Poole, Robert J.; Warwick, Richard; Poullis, Michael

    2013-01-01

    OBJECTIVES Aortic replacement is based on the aortic diameter in the absence of dissection or connective tissue diseases. Frequently, a number of different aortic-to-prosthetic anastomotic positions are possible depending on patient factors and surgeon preferences. High stress on residual aortic tissue may result in aneurysm formation or aneurysmal dilatation. Utilizing a computational fluid dynamic evaluation, we aimed to define possible optimal operative interventions with regard to the extent of aortic replacement. METHODS For proof of principle, a computational fluid dynamic (CFD) analysis, using Fluent 6.2 (Ansys UK Ltd, Sheffield, UK), was performed on a simplified ascending arch and descending aortic geometry. Wall shear stress in three dimensions was assessed for the standard operations: ascending aortic replacement, arch replacement and proximal descending aortic replacement. RESULTS Hermiarch replacement is superior to isolated ascending aortic replacement with regard to residual stress analysis on tissues (up to a 10-fold reduction). Aortic arch replacement with island implantation of the supra-aortic vessels may potentially result in high stress on the residual aorta (10-fold increase). Aortic arch replacement with individual supra-aortic vessel implantation may result in areas of high stress (10-fold increase) on native vessels if an inadequate length of supra-aortic tissue is not resected, regardless of it being aneurysmal. CONCLUSIONS Computational fluid dynamic evaluation, which will have to be patient-specific, 3D anatomical and physiological, potentially has enormous implications for operative strategy in aortic replacement surgery. CFD analysis may direct the replacement of normal-diameter aortas in the future. PMID:23407695

  1. [Emergent transcatheter aortic valve implantation in a patient with bicuspid aortic valve stenosis in cardiogenic shock].

    PubMed

    Pizzighini, S; Finet, G; Obadia, J-F; Revel, D; Bresson, D; Rioufol, G

    2015-02-01

    Transcatheter aortic valve implantation is a therapeutic option for high-risk patients with severe aortic valve stenosis and with cardiac symptoms. This procedure requires the preliminary evaluation by a "heart team" and presents some contraindications. We report the case of a 58-year-old man with severe bicuspid aortic valve stenosis and cardiogenic shock. In spite of contraindications and because of the failure of balloon aortic valvuloplasty, transcatheter aortic valve implantation was performed in emergency. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  2. 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

  3. Synthesis and Characterization of Polyfunctional Polyhedral Silsesquioxane Cages

    NASA Astrophysics Data System (ADS)

    Sulaiman, Santy

    Recent studies on octameric polyhedral silsesquioxanes, (RSiO1.5 )8, indicate that the silsesquioxane cage is not just a passive component but appears to be involved in electron delocalization with conjugated organic tethers in the excited state. This dissertation presents the synthesis and characterization of (RSiO1.5)8 molecules with unique photophysical properties that provide support for the existence of conjugation that involves the (RSiO1.5)8 cage. The dissertation first discusses the elaboration of octavinylsilsesquioxane via cross-metathesis to form styrenyl-functionalized octasilsesquioxane molecules. Subsequent Heck coupling reactions of p-bromostyrenyl derivative provides vinylstilbene-functionalized octasilsesquioxane. The amino derivative, NH2VinylStilbeneOS, show highly red-shifted emission spectrum (100 nm from the simple organic analog p-vinylstilbene) and high two-photon absorption (TPA) cross-section value (100 GM/moiety), indicating charge-transfer processes involving the silsesquioxane cage as the electron acceptor. The unique photophysical properties of polyfunctional luminescent cubic silsesquioxanes synthesized from ortho-8-, (2,5)-16-, and 24-brominated octaphenylsilsesquioxane (OPS) via Heck coupling show how the steric interactions of the organic tethers at the silsesquioxane cage corner affect conjugation with the silsesquioxane cage. Furthermore, the high TPA cross-section (10 GM/moiety) and photoluminescence quantum yield (20%) of OPS functionalized with 24 acetoxystyrenyl groups suggest that the existence excited states in these molecules with similar energies and decay rates: normal radiative pi- pi* transition and charge transfer involving the silsesquioxane cage. The fluoride ion-catalyzed rearrangement reactions of cage and polymeric silsesquioxanes provide a convenient route to a mixture of deca- and dodecameric silsesquioxane molecules in high yields, giving us the opportunity to investigate the effect of silsesquioxane cage

  4. 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

  5. Endohedral metal atoms in pristine and functionalized fullerene cages.

    PubMed

    Yamada, Michio; Akasaka, Takeshi; Nagase, Shigeru

    2010-01-19

    Fullerene, an allotropic form of carbon made up of spherical molecules formed from pentagonal and hexagonal rings, was first discovered in 1985. Because fullerenes have spacious inner cavities, atoms and clusters can be encapsulated inside the fullerene cages to form endohedral fullerenes. In particular, the unique structural and electronic properties of endohedral metallofullerenes (EMFs), where metal atoms are encapsulated within the fullerene, have attracted wide interest from physicists and chemists as well as materials scientists and biologists. The remarkable characteristics of these molecules originate in the electron transfer from the encapsulated metal atoms to the carbon cage. The positions and movements of the encapsulated metal atoms are important determinants of the chemical and physical properties of EMFs. In this Account, we specifically describe the positions and dynamic behavior of the metal atoms encapsulated in pristine and functionalized fullerene cages. First, we examined whether the metal atoms are attached rigidly to cage carbons or move around. Our systematic investigations of EMFs, including M@C(2v)-C(82), M(2)@D(2)(10611)-C(72), M(2)@D(3h)(5)-C(78), M(2)@I(h)-C(80), and M(2)@D(5h)-C(80), revealed that the metal positions and movements vary widely with different cage structures and numbers of metal atoms. Second, we wanted to understand whether we could control the positions and movements of the untouchable metal atoms in EMFs. One possible way to modulate this behavior was through attachment of a molecule to the outer surface of the cage. We developed synthetic methods to modify EMFs and have examined the metal positions and movements in the functionalized carbon cages. Remarkably, we could alter the dynamic behavior of the encaged metal atoms in M(2)@I(h)-C(80) drastically through chemical modification of the outer cage. We anticipate that the control of metal atom structures and dynamics within a cage could be valuable for designing

  6. Aortic valve replacement for aortic stenosis with a small aortic annulus in a patient having Werner's syndrome and liver cirrhosis.

    PubMed

    Sogawa, M; Kasuya, S; Yamamoto, K; Koshika, M; Oguma, F; Hayashi, J

    2001-12-01

    Werner's syndrome is a rare genetic disease characterized by premature aging and scleroderma-like involvement of the skin. We report a case of aortic valve replacement for severely calcified aortic valve stenosis with a small annulus in a patient suffering from Werner's syndrome and liver cirrhosis

  7. Dislocation of a transapically implanted aortic valve prosthesis with a functionally bicuspid aortic valve and ascending aortic aneurysm.

    PubMed

    Schroeter, T; Subramanian, S; Lehmann, S; Kempfert, J; Misfeld, M; Mohr, F W; Borger, M A

    2011-12-01

    In recent years, catheter-based aortic valve interventions have become established procedures for the treatment of high-risk and advanced age patients with aortic valve pathologies. One of the limitations of the widespread applicability of this procedure is the annulus size. Until recently, no prosthesis was available to treat patients with a large annulus. We report on a patient with high-grade aortic stenosis (AS) and a 27-mm annulus, who underwent transapical implantation (TAP) of an Edwards SAPIEN® 29-mm prosthesis (Edwards LifeScience, Irvine, CA, USA). Due to insufficient dilation of his heavily calcified, functionally bicuspid aortic valve leaflets during balloon aortic valvuloplasty (BAV), the TAP prosthesis did not anchor adequately. This was determined during follow-up as he developed progressive aortic insufficiency and orthopnea, and an echocardiography revealed that the valve had been displaced into the LVOT. A conventional aortic valve replacement and ascending aorta replacement were performed, at which time the TAP prosthesis was removed. The patient recovered uneventfully, and was discharged with a well-functioning aortic bioprosthetic valve and in good general condition. © Georg Thieme Verlag KG Stuttgart · New York.

  8. Aortic Stiffness, Cerebrovascular Dysfunction, and Memory

    PubMed Central

    Cooper, Leroy L.; Mitchell, Gary F.

    2016-01-01

    Background Aortic stiffness is associated with cardiovascular and cerebrovascular events and cognitive decline. This mini-review focuses on relations of aortic stiffness with microvascular dysfunction and discusses the contribution of abnormal pulsatile hemodynamics to cerebrovascular damage and cognitive decline. We also provide a rationale for considering aortic stiffness as a putative and important contributor to memory impairment in older individuals. Summary Aging is associated with stiffening of the aorta but not the muscular arteries, which reduces wave reflection and increases the transmission of pulsatility into the periphery. Aortic stiffening thereby impairs a protective mechanism that shields the peripheral microcirculation from excessive pulsatility within downstream target organs. Beyond midlife, aortic stiffness increases rapidly and exposes the cerebral microcirculation to abnormal pulsatile mechanical forces that are associated with microvascular damage and remodeling in the brain. Aortic stiffening and high-flow pulsatility are associated with alterations in the microvasculature of the brain; however, a mechanistic link between aortic stiffness and memory has not been established. We showed that in a community-based sample of older individuals, cerebrovascular resistance and white matter hyperintensities - markers of cerebrovascular remodeling and damage - mediated the relation between higher aortic stiffness and lower performance on memory function tests. These data suggest that microvascular and white matter damage associated with excessive aortic stiffness contribute to impaired memory function with advancing age. Key Messages Increasing evidence suggests that vascular etiologies - including aortic stiffness and microvascular damage - contribute to memory impairment and the pathogenesis of dementia, including Alzheimer's disease. Interventions that reduce aortic stiffness may delay memory decline among older individuals. PMID:27752478

  9. Egg shell colour is affected by laying cage design.

    PubMed

    Walker, A W; Hughes, B O

    1998-12-01

    1. When laying hens are stressed some retain their eggs in the shell gland beyond the normal time of laying and this can result in the deposition of extra-cuticular calcium which makes brown eggs appear paler. 2. Three different types of enriched modified cage were compared: the location where eggs were laid was recorded and shell colour was measured using a reflectometer. 3. In 2 types of cage with enclosed nest boxes more eggs (80%) were laid in the nests than in a design with nest hollows in the open part of the cage (41%). 4. The eggs from the cages with enclosed nests were darker (had less extraneous calcium) than those with open nest hollows. This implies that in the designs with nest boxes fewer eggs had been retained and the hens may have been less stressed. 5. The results support previous evidence that to reduce stress and improve welfare it is desirable to provide enclosed nest sites for caged laying hens.

  10. Pseudopeptidic cages as receptors for N-protected dipeptides.

    PubMed

    Faggi, Enrico; Moure, Alejandra; Bolte, Michael; Vicent, Cristian; Luis, Santiago V; Alfonso, Ignacio

    2014-05-16

    The molecular recognition of short peptides is a challenge in supramolecular chemistry, and the use of peptide-like cage receptors represents a promising approach. Here we report the synthesis and characterization of a diverse family of pseudopeptidic macrobicycles, as well as their binding abilities toward N-protected dipeptides using a combination of different techniques (NMR, ESI-MS, and fluorescence spectroscopy). The cage hosts were assayed for dipeptide binding using competition ESI-MS experiments as high-throughput screening to obtain general trends for the recognition phenomena. Selected hosts were additionally studied by NMR spectroscopy ((1)H NMR titration and diffusion-ordered spectroscopy experiments) in different solvents. The results unambiguously demonstrated the formation of the [cage·dipeptide] supramolecular complexes and rendered quantitative information about the strength of the interaction (K(ass)). The structural variables within the pseudopeptidic cage framework that produced a stronger and more selective recognition were thus identified. The cages showed a remarkable selectivity for N-protected dipeptides with an aromatic amino acid at the carboxylic terminus, which prompted us to propose a mode of binding based on polar and nonpolar noncovalent interactions. Accordingly, we faced the molecular recognition of a target dipeptide (Ac-EY-OH) mimicking a biologically relevant sequence by NMR and fluorescence spectroscopy in highly competitive media.

  11. Comparison of 2 Rat Breeding Schemes Using Conventional Caging

    PubMed Central

    Allen, Kenneth P; Dwinell, Melinda R; Zappa, Allison; Temple, Anne; Thulin, Joseph

    2013-01-01

    Compared with earlier editions, the eighth edition of the Guide for the Care and Use of Laboratory Animals recommends more cage floor space for female rats with litters. As such, conventional rat cages often do not supply the recommended floor space to maintain 2 adult rats and a litter in the same cage. We evaluated 2 breeding schemes using traditional cages that afford 140 in.2 (903 cm2) of floor space: (1) monogamous pairs housed continuously and (2) monogamous pairs cohoused intermittently with removal of the male rat after parturition. The results did not demonstrate a significant difference between breeding schemes in generation time, number of litters per breeding pair, percentage of litters weaned, number of pups born per breeding pair, and number of pups weaned per breeding pair. However, the average weaning weight of pups was significantly higher with scheme 1 compared with scheme 2. Collectively, these results indicate continuous housing of monogamous breeding pairs may be preferable to intermittent housing when conventional cages are used. PMID:23562096

  12. High levitation pressures with cage-cooled superconductors

    NASA Astrophysics Data System (ADS)

    Hull, John R.; Komori, Mochimitsu

    2002-05-01

    We present an analysis of and experimental results from a levitational system comprising a stationary, bulk high-temperature superconductor (HTS) and a levitated component (rotor) that consists of a cylindrical permanent magnet surrounded by an annular HTS. The rotor is cooled below the critical temperature of the HTS while surrounded by a ferromagnetic cage. When the ferromagnetic cage is removed, the flux from the permanent magnet is essentially excluded from the interior of the HTS. When brought into proximity with the HTS stator, the cage-cooled rotor experiences a levitational force. The levitational force may be calculated by applying magnetic circuit theory. Such calculations indicate that for a sufficiently high critical current density, the levitational pressure may exceed that between the permanent magnet and its mirror image. We constructed a rotor from an NdFeB permanent magnet and YBCO bulk HTS with a critical current density of ≈5 kA cm-2. A soft ferromagnetic steel cage was constructed in segments. The critical current density of the stator HTS was also ≈5 kA cm-2. Experimental results obtained with the cage-cooled rotor and stationary HTS show a significant increase in force over that of an equivalent PM rotor and stationary HTS.

  13. 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.

  14. 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

  15. Aortic annuloplasty with aortic root reconstruction to prevent patient-prosthesis mismatch.

    PubMed

    Hopkins, Richard A

    2006-07-01

    Part of the ongoing argument concerning patient-prosthesis mismatch (PPM) following aortic valve replacement (AVR) is due to the perception that aortic annulus enlargement procedures increase the risk and technical difficulty of aortic valve surgery. Here, an aortic root reconstruction that involves enlargement of the annulus and tailoring of the aortic root to accommodate larger stented prostheses is presented that has been personally performed in 196 patients with no technique-related surgical deaths or complications, and thus can be carried out without additional risk. This aortic root enlargement aortoplasty and annuloplasty method can be calibrated to all AVRs involving stented manufactured prostheses when these are deemed the prosthesis of choice for the patient with a relatively small annulus and/or aortic root, severe left ventricular hypertrophy, compromised LV function or a very active lifestyle, to achieve predicted EOA values > or = 1.00 cm2/m2.

  16. [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.

  17. Sutureless Medtronic 3f Enable aortic valve replacement in a heavily calcified aortic root.

    PubMed

    Vola, Marco; Fuzellier, Jean-Francois; Kasra, Azarnoush; Morel, Jérôme; Campisi, Salvatore; Ruggeri, Gianvito; Favre, Jean Pierre

    2013-05-01

    The case is reported of a surgical aortic valvular stenosis with a severely calcified ascending aortic root in a 76-year-old woman. The morphology and size of the aortic annulus were unsuitable for transcatheter aortic valve implantation (TAVI); thus, surgery was scheduled. Aortic calcifications allowed a transverse aortotomy 4 cm superior to the sinotubular junction, with a remote endoaortic view of the valve. A Medtronic 3f Enable sutureless bioprosthesis was then implanted after aortic annular decalcification. Sutureless bioprostheses are new tools that promise to reduce technical difficulties and cross-clamp times in minimally invasive aortic valve replacement surgery. In addition, sutureless techniques may have other possible advantages in special circumstances requiring full sternotomy access, such as in the present case.

  18. Performance and welfare of laying hens in conventional and enriched cages.

    PubMed

    Tactacan, G B; Guenter, W; Lewis, N J; Rodriguez-Lecompte, J C; House, J D

    2009-04-01

    Concerns regarding the welfare of laying hens raised in battery cages have led to the development of enriched cages that allow hens to perform natural behaviors including nesting, roosting, and scratching. This study was conducted to compare indices of production and welfare in birds housed in 2 different caging systems. Shaver White hens were housed from 21 to 61 wk in either conventional battery cages (n = 500; 10 cages; 5 hens/cage; floor space = 561.9 cm(2)/hen) or enriched cages (n = 480; 2 cages; 24 hens/cage; floor space = 642.6 cm(2)/hen) and were replicated 10 times. Enriched cages provided hens with a curtained nesting area, scratch pad, and perches. Production parameters and egg quality measures were recorded throughout the experiment. Plumage condition was evaluated at 37 and 61 wk. Bone quality traits and immunological response parameters were measured at 61 wk, and 59 and 61 wk, respectively. Hen-day egg production, feed consumption, egg weight, and percentage of cumulative mortality of laying hens were not affected by the cage designs. Specific gravity and the percentage of cracked and soft-shelled eggs were also similar between the 2 housing systems. The incidence of dirty eggs was, however, significantly higher (P < 0.0001) in enriched cages than in conventional cages. Feather scores were similar between birds except for the wing region, which was higher (P < 0.05) for hens housed in conventional cages. Bone quality measures tended to be higher for hens housed in enriched cages compared with hens in conventional cages. However, the increase was significant only for bone mineral density. Immunological response parameters did not reveal statistically significant differences. Overall, laying performance, exterior egg quality measures, plumage condition, and immunological response parameters appear to be similar for hens housed in the 2 cage systems tested. Enrichment of laying hen cages resulted in better bone quality, which could have resulted from

  19. Recent advances in aortic valve replacement for aortic stenosis

    PubMed Central

    Al-Adhami, Ahmed; Al-Attar, Nawwar

    2016-01-01

    Aortic valve replacement is no longer an operation that is approached solely through a median sternotomy. Recent advances in the fields of transcatheter valves have expanded the proportion of patients eligible for intervention. Comparisons between transcatheter valves and conventional surgery have shown non-inferiority of transcatheter valve implants in patients with a high or intermediate pre-operative predictive risk. With advances in our understanding of sutureless valves and their applicability to minimally invasive surgery, the invasiveness and trauma of surgery can be reduced with potential improvements in outcome. The strategy of care has radically changed over the last decade. PMID:27803800

  20. Biomechanical characterization of ascending aortic aneurysm with concomitant bicuspid aortic valve and bovine aortic arch.

    PubMed

    Pham, T; Martin, C; Elefteriades, J; Sun, W

    2013-08-01

    Studies have shown that patients harboring bicuspid aortic valve (BAV) or bovine aortic arch (BAA) are more likely than the general population to develop ascending aortic aneurysm (AsAA). A thorough quantification of the AsAA tissue properties for these patient groups may offer insights into the underlying mechanisms of AsAA development. Thus, the objective of this study was to investigate and compare the mechanical and microstructural properties of aortic tissues from AsAA patients with and without concomitant BAV or BAA. AsAA (n=20), BAV (n=20) and BAA (n=15) human tissues were obtained from patients who underwent elective AsAA surgery. Planar biaxial and uniaxial failure tests were used to characterize the mechanical and failure properties of the tissues, respectively. Histological analysis was performed to detect medial degenerative characteristics of aortic aneurysm. Individual layer thickness and composition were quantified for each patient group. The circumferential stress-strain response of the BAV samples was stiffer than both AsAA (p=0.473) and BAA (p=0.152) tissues at a low load. The BAV samples were nearly isotropic, while AsAA and BAA samples were anisotropic. The areal strain of BAV samples was significantly less than that of AsAA (p=0.041) and BAA (p=0.004) samples at a low load. The BAA samples were similar to the AsAA samples in both mechanical and failure properties. On the microstructural level, all samples displayed moderate medial degeneration, characterized by elastin fragmentation, cell loss, mucoid accumulation and fibrosis. The ultimate tensile strength of BAV and BAA sampleswere also found to decrease with age. Overall, the BAV samples were stiffer than both AsAA and BAA samples, and the BAA samples were similar to the AsAA samples. The BAV samples were thinnest, with less elastin than AsAA and BAA samples, which may be attributed to the loss of extensibility of these tissues at a low load. No apparent difference in failure mechanics among

  1. Anterior cervical corpectomy: review and comparison of results using titanium mesh cages and carbon fibre reinforced polymer cages.

    PubMed

    Kabir, Syed M R; Alabi, J; Rezajooi, Kia; Casey, Adrian T H

    2010-10-01

    Different types of cages have recently become available for reconstruction following anterior cervical corpectomy. We review the results using titanium mesh cages (TMC) and stackable CFRP (carbon fibre reinforced polymer) cages. Forty-two patients who underwent anterior cervical corpectomy between November 2001 and September 2008 were retrospectively reviewed. Pathologies included cervical spondylotic myelopathy (CSM), cervical radiculopathy, OPLL (ossified posterior longitudinal ligament), metastasis/primary bone tumour, rheumatoid arthritis and deformity correction. All patients were evaluated clinically and radiologically. Outcome was assessed on the basis of the Odom's criteria, neck disability index (NDI) and myelopathy disability index (MDI). Mean age was 60 years and mean follow-up was 1½ years. Majority of the patients had single-level corpectomy. Twenty-three patients had TMC cages while 19 patients had CFRP cages. The mean subsidence noted with TMC cage was 1.91 mm, while with the stackable CFRP cage it was 0.5 mm. This difference was statistically significant (p < 0.05). However, there was no statistically significant correlation noted between subsidence and clinical outcome (p > 0.05) or between subsidence and post-operative sagittal alignment (p > 0.05) in either of the groups. Three patients had significant subsidence (> 3 mm), one of whom was symptomatic. There were no hardware-related complications. On the basis of the Odom's criterion, 9 patients (21.4%) had an excellent outcome, 14 patients (33.3%) had a good outcome, 9 patients (21.4%) had a fair outcome and 5 patients (11.9%) had a poor outcome, i.e. symptoms and signs unchanged or exacerbated. Mean post-operative NDI was 26.27% and mean post-operative MDI was 19.31%. Fusion was noted in all 42 cases. Both TMC and stackable CFRP cages provide solid anterior column reconstruction with good outcome following anterior cervical corpectomy. However, more subsidence is noted with TMC cages though

  2. The rib cage stabilizes the human thoracic spine: An in vitro study using stepwise reduction of rib cage structures

    PubMed Central

    Liebsch, Christian; Graf, Nicolas; Appelt, Konrad

    2017-01-01

    The stabilizing effect of the rib cage on the human thoracic spine is still not sufficiently analyzed. For a better understanding of this effect as well as the calibration and validation of numerical models of the thoracic spine, experimental biomechanics data is required. This study aimed to determine (1) the stabilizing effect of the single rib cage structures on the human thoracic spine as well as the effect of the rib cage on (2) the flexibility of the single motion segments and (3) coupled motion behavior of the thoracic spine. Six human thoracic spine specimens including the entire rib cage were loaded quasi-statically with pure moments of ± 2 Nm in flexion/extension (FE), lateral bending (LB), and axial rotation (AR) using a custom-built spine tester. Motion analysis was performed using an optical motion tracking system during load application to determine range of motion (ROM) and neutral zone (NZ). Specimens were tested (1) in intact condition, (2) after removal of the intercostal muscles, (3) after median sternotomy, after removal of (4) the anterior rib cage up to the rib stumps, (5) the right sixth to eighth rib head, and (6) all rib heads. Significant (p < 0.05) increases of the ROM were found after dissecting the intercostal muscles (LB: + 22.4%, AR: + 22.6%), the anterior part of the rib cage (FE: + 21.1%, LB: + 10.9%, AR: + 72.5%), and all rib heads (AR: + 5.8%) relative to its previous condition. Compared to the intact condition, ROM and NZ increased significantly after removing the anterior part of the rib cage (FE: + 52.2%, + 45.6%; LB: + 42.0%, + 54.0%; AR: + 94.4%, + 187.8%). Median sternotomy (FE: + 11.9%, AR: + 21.9%) and partial costovertebral release (AR: + 11.7%) significantly increased the ROM relative to its previous condition. Removing the entire rib cage increased both monosegmental and coupled motion ROM, but did not alter the qualitative motion behavior. The rib cage has a strong effect on thoracic spine rigidity, especially in

  3. The rib cage stabilizes the human thoracic spine: An in vitro study using stepwise reduction of rib cage structures.

    PubMed

    Liebsch, Christian; Graf, Nicolas; Appelt, Konrad; Wilke, Hans-Joachim

    2017-01-01

    The stabilizing effect of the rib cage on the human thoracic spine is still not sufficiently analyzed. For a better understanding of this effect as well as the calibration and validation of numerical models of the thoracic spine, experimental biomechanics data is required. This study aimed to determine (1) the stabilizing effect of the single rib cage structures on the human thoracic spine as well as the effect of the rib cage on (2) the flexibility of the single motion segments and (3) coupled motion behavior of the thoracic spine. Six human thoracic spine specimens including the entire rib cage were loaded quasi-statically with pure moments of ± 2 Nm in flexion/extension (FE), lateral bending (LB), and axial rotation (AR) using a custom-built spine tester. Motion analysis was performed using an optical motion tracking system during load application to determine range of motion (ROM) and neutral zone (NZ). Specimens were tested (1) in intact condition, (2) after removal of the intercostal muscles, (3) after median sternotomy, after removal of (4) the anterior rib cage up to the rib stumps, (5) the right sixth to eighth rib head, and (6) all rib heads. Significant (p < 0.05) increases of the ROM were found after dissecting the intercostal muscles (LB: + 22.4%, AR: + 22.6%), the anterior part of the rib cage (FE: + 21.1%, LB: + 10.9%, AR: + 72.5%), and all rib heads (AR: + 5.8%) relative to its previous condition. Compared to the intact condition, ROM and NZ increased significantly after removing the anterior part of the rib cage (FE: + 52.2%, + 45.6%; LB: + 42.0%, + 54.0%; AR: + 94.4%, + 187.8%). Median sternotomy (FE: + 11.9%, AR: + 21.9%) and partial costovertebral release (AR: + 11.7%) significantly increased the ROM relative to its previous condition. Removing the entire rib cage increased both monosegmental and coupled motion ROM, but did not alter the qualitative motion behavior. The rib cage has a strong effect on thoracic spine rigidity, especially in

  4. Endovascular approach to acute aortic trauma

    PubMed Central

    Karmy-Jones, Riyad; Teso, Desarom; Jackson, Nicole; Ferigno, Lisa; Bloch, Robert

    2009-01-01

    Traumatic thoracic aortic injury remains a major cause of death following motor vehicle accidents. Endovascular approaches have begun to supersede open repair, offering the hope of reduced morbidity and mortality. The available endovascular technology is associated with specific anatomic considerations and complications. This paper will review the current status of endovascular management of traumatic thoracic aortic injuries. PMID:21160721

  5. Aortic Valve Calcification in Mild Primary Hyperparathyroidism

    PubMed Central

    Iwata, Shinichi; Walker, Marcella Donovan; Di Tullio, Marco R.; Hyodo, Eiichi; Jin, Zhezhen; Liu, Rui; Sacco, Ralph L.; Homma, Shunichi

    2012-01-01

    Context: It is unclear whether cardiovascular disease is present in primary hyperparathyroidism (PHPT). Objective: Aortic valve structure and function were compared in PHPT patients and population-based controls. Design: This is a case-control study. Setting: The study was conducted in a university hospital metabolic bone disease unit. Participants: We studied 51 patients with PHPT and 49 controls. Outcome Measures: We measured the aortic valve calcification area and the transaortic pressure gradient. Results: Aortic valve calcification area was significantly higher in PHPT (0.24 ± 0.02 vs. 0.17 ± 0.02 cm2, p<0.01), although there was no difference in the peak transaortic pressure gradient, a functional measure of valvular calcification (5.6 ± 0.3 vs. 6.0 ± 0.3 mm Hg, P = 0.39). Aortic valve calcification area was positively associated with PTH (r = 0.34; P < 0.05) but not with serum calcium, phosphorus, or 25-hydroxyvitamin D levels or with calcium-phosphate product. Serum PTH level remained an independent predictor of aortic valve calcification area after adjustment for age, sex, body mass index, smoking status, history of hypercholesterolemia and hypertension, and estimated glomerular filtration rate. Conclusions: Mild PHPT is associated with subclinical aortic valve calcification. PTH, but not serum calcium concentration, predicted aortic valve calcification. PTH was a more important predictor of aortic valve calcification than well-accepted cardiovascular risk factors. PMID:22031523

  6. Late complication after repair of aortic coarctation.

    PubMed

    Lemaire, Anaïs; Cuttone, Fabio; Desgué, Julien; Ivascau, Calin; Caprio, Sabino; Saplacan, Vladimir; Belin, Annette; Babatasi, Gérard

    2015-05-01

    Coarctation of the aorta is a congenital malformation that has long been considered completely correctable with appropriate surgery in childhood. However, with the aging of these patients, many late complications have been reported, and this notion must be reevaluated. We retrospectively reviewed all patients who underwent reoperation between 1992 and 2012 in our adult cardiac surgery department following surgical correction of coarctation in childhood; 18 patients over 15-years old were included in the study. The median time from coarctation repair to reoperation was 25 years. Patients were reoperated on for several late complications: aortic valve disease secondary to bicuspid aortic valve, ascending aortic aneurysm, recoarctation, aortic arch hypoplasia, pseudoaneurysm, associated recoarctation and pseudoaneurysm, subvalvular aortic obstruction, and descending thoracic aortic aneurysm. One patient died due to an intraoperative complication. In the other cases, the surgical results were satisfactory at the 6-month follow-up. According to literature data, age at coarctation repair and surgical technique appear to be essential factors in late complications: older age and surgical repair with prosthesis interposition are associated with a higher rate of reintervention. Patients who have undergone repair of aortic coarctation frequently remain asymptomatic for a long time. Late complications can be appropriately treated when diagnosed early. Consequently, all coarctation patients need careful lifelong follow-up, especially those with congenital aortic valve disease or surgery in childhood with interposition of prosthetic material. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  7. Encapsulation of cobalt nanoparticles in cross-linked-polymer cages

    NASA Astrophysics Data System (ADS)

    Hatamie, Shadie; Dhole, S. D.; Ding, J.; Kale, S. N.

    2009-07-01

    Nanoparticles embedded in polymeric cages give rise to interesting applications ranging from nanocatalysis to drug-delivery systems. In this context, we report on synthesis of cobalt (Co) nanoparticles trapped in polyvinyl alcohol (PVA) matrix to yield self-supporting magnetic films in PVA slime. A 20 nm, Co formed in FCC geometry encapsulated with a weak citrate coat when caged in PVA matrix exhibited persistence of magnetism and good radio-frequency response. Cross-linking of PVA chains to form cage-like structures to arrest Co nanoparticles therein, is believed to be the reason for oxide-free nature of Co, promising applications in biomedicine as well as in radio-frequency shielding.

  8. The cage effect in systems of hard spheres

    NASA Astrophysics Data System (ADS)

    van Megen, W.; Schöpe, H. J.

    2017-03-01

    The cage effect is generally invoked when discussing the delay in the decay of time correlation functions of dense fluids. In an attempt to examine the role of caging more closely, we consider the spread of the displacement distributions of Brownian particles. These distributions are necessarily biased by the presence of neighbouring particles. Accommodation of this bias by those neighbours conserves the displacement distribution locally and presents a collective mechanism for exploring configuration space that is more efficient than the intrinsic Brownian motion. Caging of some particles incurs, through the impost of global conservation of the displacement distribution, a delayed, non-local collective process. This non-locality compromises the efficiency with which configuration space is explored. Both collective mechanisms incur delay or stretching of time correlation functions, in particular the particle number and flux densities. This paper identifies and distinguishes these mechanisms in existing data from experiments and computer simulations on systems of particles with hard sphere interactions.

  9. 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

  10. [Acute aortic syndromes and sleep apnea].

    PubMed

    Baguet, Jean-Philippe

    2016-10-01

    Obstructive sleep apnea (OSA) is a common disease, often present in "cardiovascular or metabolic patients". OSA favours the occurrence of arterial lesions, all the more if severe. There is a strong relationship between OSA and acute aortic syndromes (AAS). This relationship is in part explained by aortic dilatation linked to OSA. The presence of repeated episodes of sudden variation of transmural pressure applied on aortic wall seems to play a major role in this dilatation. All OSA patients should have a search of aortic dilatation by ultrasound (at a thoracic and abdominal level). Also, screening of OSA should be systematically performed in patients with aortic disease. The effect of continuous positive airway pressure in apneic patients with AAS has not been studied.

  11. Valvular and aortic diseases in osteogenesis imperfecta.

    PubMed

    Lamanna, Arvin; Fayers, Trevor; Clarke, Sophie; Parsonage, William

    2013-10-01

    Osteogenesis imperfecta (OI) is an inheritable connective tissue disorder caused by defective collagen synthesis with the principal manifestations of bone fragility. OI has been associated with left sided valvular regurgitation and aortic dilation. Valve and aortic surgery are technically feasible in patients with OI but are inherently high risk due to the underlying connective tissue defect. This report reviews the valvular and aortic pathology associated with OI and their management. We describe two cases of patients with OI who have significant aortic and mitral valve regurgitation, one of whom has been managed conservatively and the other who has undergone successful mitral valve repair and aortic valve replacement. The latter case represents the fifth case of mitral valve repair in a patient with OI reported in the medical literature. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  12. 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.

  13. 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.

  14. Late entrapment of ball and cage valve in mitral position.

    PubMed

    Akbari, Jayesh G; Varma, Praveen K; Gadhinglajkar, Shrinivas V; Neelakandhan, Kurur S

    2006-02-01

    A 32-year-old female underwent mitral valve replacement with total chordal preservation (Miki's technique) using 26 mm (1M) Starr-Edward prosthesis (SEP) in 1988. The patient was in NYHA class-I until 2001. She progressed to NYHA class-III with paroxysmal nocturnal dyspnoea. Transthoracic echocardiogram showed increased prosthetic valve gradient, and cardiac catheterization confirmed the findings. Intraoperatively, the poppet movement in the cage was found to be restricted due to the preserved subvalvular apparatus entrapping the poppet inside the prosthetic valve cage.

  15. Low-gradient aortic stenosis

    PubMed Central

    Clavel, Marie-Annick; Magne, Julien; Pibarot, Philippe

    2016-01-01

    An important proportion of patients with aortic stenosis (AS) have a ‘low-gradient’ AS, i.e. a small aortic valve area (AVA <1.0 cm2) consistent with severe AS but a low mean transvalvular gradient (<40 mmHg) consistent with non-severe AS. The management of this subset of patients is particularly challenging because the AVA-gradient discrepancy raises uncertainty about the actual stenosis severity and thus about the indication for aortic valve replacement (AVR) if the patient has symptoms and/or left ventricular (LV) systolic dysfunction. The most frequent cause of low-gradient (LG) AS is the presence of a low LV outflow state, which may occur with reduced left ventricular ejection fraction (LVEF), i.e. classical low-flow, low-gradient (LF-LG), or preserved LVEF, i.e. paradoxical LF-LG. Furthermore, a substantial proportion of patients with AS may have a normal-flow, low-gradient (NF-LG) AS: i.e. a small AVA—low-gradient combination but with a normal flow. One of the most important clinical challenges in these three categories of patients with LG AS (classical LF-LG, paradoxical LF-LG, and NF-LG) is to differentiate a true-severe AS that generally benefits from AVR vs. a pseudo-severe AS that should be managed conservatively. A low-dose dobutamine stress echocardiography may be used for this purpose in patients with classical LF-LG AS, whereas aortic valve calcium scoring by multi-detector computed tomography is the preferred modality in those with paradoxical LF-LG or NF-LG AS. Although patients with LF-LG severe AS have worse outcomes than those with high-gradient AS following AVR, they nonetheless display an important survival benefit with this intervention. Some studies suggest that transcatheter AVR may be superior to surgical AVR in patients with LF-LG AS. PMID:27190103

  16. Diagnostic imaging for aortic dissection.

    PubMed

    Kapustin, Andrew J; Litt, Harold I

    2005-01-01

    Diagnostic imaging for aortic dissection has dramatically changed in recent years. Previously, imaging consisted of conventional X-ray radiography, followed by invasive catheter angiography. Now imaging of dissection is performed primarily with multidetector CT, and to a lesser extent, with ultrasound and MRI. Catheter angiography is used primarily as a means of treating complications. Which modality to choose depends on patient factors, physician preference, and differences in availability of state-of-the-art equipment. All three modalities are highly accurate in experienced hands and have revolutionized the detection and evaluation of this condition.

  17. [Non-aneurysmatic aortic dysphagia].

    PubMed

    Rivera, P; Ferrer, L; Tuset, J A; Pamos, S; López Mut, J; Luján, M; Tomé, A; Medina, E

    1999-01-01

    Esophageal compression by a vascular structure is a rare cause of dysphagia, the aberrant right subclavian artery being the most common congenital abnormality. Aortica dysphagia is usually observed in the elderly, especially in hypertensive women with cardiopathy and degenerative osteopathy. We report a 73-year-old woman with dysphagia, caused by a non-aneurysmatic aortic elongation, who presented progressive dysphagia, which ended in aphagia associated with heart failure. The diagnostic approach to these patients is discussed. The patient received cinitapride and, following treatment for heart failure, remains asymptomatic after a 3-year follow-up period, although manometric alterations persist.

  18. Abdominal Aortic Surgery: Anesthetic Implications

    PubMed Central

    Cunningham, Anthony J.

    1991-01-01

    The objectives of the review are to highlight the clinical characteristics of the patient population; to assess multivariate risk factor analysis and the invasive/non-invasive techniques available for risk factor identification and management in this high-risk surgical population; to assess the major hemodynamic, metabolic, and regional blood flow changes associated with aortic cross-clamping/unclamping procedures and techniques for their modification or attenuation; and to assess the influence of perioperative anesthetic techniques and management on patient outcome. PMID:1814052

  19. [Modern aortic surgery in Marfan syndrome--2011].

    PubMed

    Kallenbach, K; Schwill, S; Karck, M

    2011-09-01

    Marfan syndrome is a hereditary disease with a prevalence of 2-3 in 10,000 births, leading to a fibrillin connective tissue disorder with manifestations in the skeleton, eye, skin, dura mater and in particular the cardiovascular system. Since other syndromes demonstrate similar vascular manifestations, but therapy may differ significantly, diagnosis should be established using the revised Ghent nosology in combination with genotypic analysis in specialized Marfan centres. The formation of aortic root aneurysms with the subsequent risk of acute aortic dissection type A (AADA) or aortic rupture limits life expectancy in patients with Marfan syndrome. Therefore, prophylactic replacement of the aortic root needs to be performed before the catastrophic event of AADA can occur. The goal of surgery is the complete resection of pathological aortic tissue. This can be achieved with excellent results by using a (mechanically) valved conduit that replaces both the aortic valve and the aortic root (Bentall operation). However, the need for lifelong anticoagulation with Coumadin can be avoided using the aortic valve sparing reimplantation technique according to David. The long-term durability of the reconstructed valve is favourable, and further technical improvements may improve longevity. Although results of prospective randomised long-term studies comparing surgical techniques are lacking, the David operation has become the surgical method of choice for aortic root aneurysms, not only at the Heidelberg Marfan Centre. Replacement of the aneurysmal dilated aortic arch is performed under moderate hypothermic circulatory arrest combined with antegrade cerebral perfusion using a heart-lung machine, which we also use in thoracic or thoracoabdominal aneurysms. Close post-operative follow-up in a Marfan centre is pivotal for the early detection of pathological changes on the diseased aorta.

  20. 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.

  1. Risk of rupture or dissection in descending thoracic aortic aneurysm.

    PubMed

    Kim, Joon Bum; Kim, Kibeom; Lindsay, Mark E; MacGillivray, Thomas; Isselbacher, Eric M; Cambria, Richard P; Sundt, Thoralf M

    2015-10-27

    Current practice guidelines recommend surgical repair of large thoracic aortic aneurysms to prevent fatal aortic dissection or rupture, but limited natural history data exist to support clinical criteria for timely intervention. Of 3247 patients with thoracic aortic aneurysm registered in our institutional Thoracic Aortic Center Database, we identified and reviewed 257 nonsyndromic patients (age, 72.4±10.5 years; 143 female) with descending thoracic or thoracoabdominal aortic aneurysm without a history of aortic dissection in whom surgical intervention was not undertaken. The primary end point was a composite of aortic dissection/rupture and sudden death. Baseline mean maximal aortic diameter was 52.4±10.8 mm, with 103 patients having diameters ≥55 mm. During a median follow-up of 25.1 months (quartiles 1-3, 8.3-56.4 months), definite and possible aortic events occurred in 19 (7.4%) and 31 (12.1%) patients, respectively. On multivariable analyses, maximal aortic diameter at baseline emerged as the only significant predictor of aortic events (hazard ratio=1.12; 95% confidence interval, 1.08-1.15). Estimated rates of definite aortic events within 1 year were 5.5%, 7.2%, and 9.3% for aortic diameters of 50, 55, and 60 mm, respectively. Receiver-operating characteristic curves for discriminating aortic events were higher for indexed aortic sizes referenced by body size (area under the curve=0.832-0.889) but not significantly different from absolute maximal aortic diameter (area under the curve=0.805). Aortic size was the principal factor related to aortic events in unrepaired descending thoracic or thoracoabdominal aortic aneurysm. Although the risk of aortic events started to increase with a diameter >5.0 to 5.5 cm, it is uncertain whether repair of thoracic aortic aneurysms in this range leads to overall benefit, and the threshold for repair requires further evaluation. © 2015 American Heart Association, Inc.

  2. Role of Cardiac CT Before Transcatheter Aortic Valve Implantation (TAVI).

    PubMed

    Marwan, Mohamed; Achenbach, Stephan

    2016-02-01

    Catheter-based aortic valve implantation is increasingly being performed in high-risk patients with symptomatic aortic valve stenosis. For successful planning of the procedure, CT has been shown to provide crucial information concerning the aortic root as well as the peripheral access vessels. This article illustrates the increasing role of CT before transcatheter aortic valve implantation.

  3. Improved technique of transapical aortic valve implantation: "the Berlin addition".

    PubMed

    Pasic, Miralem; Dreysse, Stephan; Drews, Thorsten; Buz, Semih; Unbehaun, Axel; Kukucka, Marian; Mladenow, Alexandar; Hetzer, Roland

    2010-06-01

    Transapical aortic valve implantation carries some degree of uncertainty regarding the definitive valve position. We added angiographic visualization of the aortic root while the prosthetic valve is being slowly deployed. It enables easy correction of the position of the valve so that perfect alignment can be achieved of the relationships between the prosthetic valve, aortic valve annulus, aortic cusps, and the coronary arteries.

  4. Aortic valve and ascending aortic root modeling from 3D and 3D+t CT

    NASA Astrophysics Data System (ADS)

    Grbic, Saša; Ionasec, Razvan I.; Zäuner, Dominik; Zheng, Yefeng; Georgescu, Bogdan; Comaniciu, Dorin

    2010-02-01

    Aortic valve disorders are the most frequent form of valvular heart disorders (VHD) affecting nearly 3% of the global population. A large fraction among them are aortic root diseases, such as aortic root aneurysm, often requiring surgical procedures (valve-sparing) as a treatment. Visual non-invasive assessment techniques could assist during pre-selection of adequate patients, planning procedures and afterward evaluation of the same. However state of the art approaches try to model a rather short part of the aortic root, insufficient to assist the physician during intervention planning. In this paper we propose a novel approach for morphological and functional quantification of both the aortic valve and the ascending aortic root. A novel physiological shape model is introduced, consisting of the aortic valve root, leaflets and the ascending aortic root. The model parameters are hierarchically estimated using robust and fast learning-based methods. Experiments performed on 63 CT sequences (630 Volumes) and 20 single phase CT volumes demonstrated an accuracy of 1.45mm and an performance of 30 seconds (3D+t) for this approach. To the best of our knowledge this is the first time a complete model of the aortic valve (including leaflets) and the ascending aortic root, estimated from CT, has been proposed.

  5. Nontraumatic avulsion of aortic valve commissure as a cause of acute aortic valve regurgitation

    PubMed Central

    Chang, Rei-Yeuh; Chen, Chien-Chang; Hsu, Wei-Pang; Hsiao, Pei-Ching; Tsai, Han-Lin; Hsiao, Ping-Gune; Wu, Jiann-Der; Guo, How-Ran

    2016-01-01

    Abstract Background: Avulsion of the aortic valve commissure as a cause of acute aortic valve regurgitation is mostly due to trauma, infective endocarditis, or ascending aortic dissection. Nontraumatic avulsion of the aortic valve commissure is very rare. We reviewed the literature and analyzed potential risk factors of nontraumatic avulsion. Case presentation: An 80-year-old male with hypertension was seen in the emergency department with acute onset dyspnea. Echocardiogram revealed left ventricular hypertrophy with adequate systolic function, prolapse of the noncoronary cusp, and incomplete coaptation of the right coronary and noncoronary cusps with severe aortic valve regurgitation. Surgery revealed an avulsion between the left coronary and noncoronary cusps. Histopathology examination of the aortic valve showed myxoid degeneration, fibrosis, and calcification. Examination of the ascending aorta revealed myxoid degeneration and fragmentation of elastic fibers. Aortic valve replacement was performed, and the patient was alive and well 4 years after surgery. A review of the literature showed that more than three-fourths of the similar cases occurred in males, and about half in patients with hypertension and those 60 years of age or older. Conclusions: In the case of acute aortic regurgitation without a history of trauma, infection, or valvotomy, when 2 prolapsed aortic cusps are observed by echocardiography in the absence of an intimal tear of the ascending aorta, an avulsion of the aortic commissure should be suspected, especially in males with hypertension who are 60 years of age or older. PMID:27749570

  6. The association between aortic regurgitation and undetermined embolic infarction with aortic complex plaque.

    PubMed

    Kim, Dae-Won; Cho, Jung Sun; Cho, Jae Yeong; Kim, Kye Hun; Sun, Byung Joo; Park, Jae-Hyeong

    2017-01-01

    Background Retrograde embolism from the descending thoracic aorta is one possible cause of undetermined ischemic stroke. Significant aortic regurgitation can increase the amount of reversed flow in the thoracic aorta and thus is associated with an increased incidence of stroke. Aims This study aimed to examine the association between significant aortic regurgitation and undetermined embolic infarction with aortic complex plaques. Methods This study included 380 patients with undetermined embolic stroke who did not have abnormal flow such as atrial septal defect, patent foramen ovale determined by agitated saline bubble test, intracardiac thrombi on transesophageal echocardiography, atrial fibrillation, or small vessel stroke, cerebral artery, and carotid stenosis on the brain magnetic resonance imaging. The patients were divided into the complex aortic plaques group (n = 63), which was defined as having plaque with >4 mm in thickness, ulceration, or high mobility, and the no complex aortic plaques group (n = 317). Results Transesophageal echocardiography with a bubble study, brain MRI, and laboratory tests were performed for all subjects. Significant aortic regurgitation was more prevalent in patients with undetermined embolic stroke and complex aortic plaques than in patients without complex aortic plaques (adjusted OR = 4.981; 95% CI = 1.323-18.876, P = 0.028). In addition, the distribution of complex aortic plaques according to the severity of aortic regurgitation in patients with undetermined embolic stroke had a tendency toward the ascending thoracic aorta and proximal aortic arch. Conclusions Significant aortic regurgitation may affect undetermined embolic stroke in patients with complex aortic plaques.

  7. Aortic disease in patients with Marfan syndrome: aortic volume assessment for surveillance.

    PubMed

    den Hartog, Alexander W; Franken, Romy; de Witte, Piet; Radonic, Teodora; Marquering, Henk A; van der Steen, Wessel E; Timmermans, Janneke; Scholte, Arthur J; van den Berg, Maarten P; Zwinderman, Aeilko H; Mulder, Barbara J M; Groenink, Maarten

    2013-11-01

    To assess the reproducibility of aortic volume estimates and to serially test their use in patients with Marfan syndrome. The study was approved by the medical ethics committee and all subjects gave written informed consent. In 81 patients with Marfan syndrome and seven healthy control subjects, aortic volumes and diameters at baseline were estimated by means of contrast material-enhanced magnetic resonance (MR) imaging. At 3 years of follow-up, aortic expansion rate were calculated in a subgroup of 22 patients with Marfan syndrome. Total aortic volume was defined as volume measurement from the level of the aortic annulus to the aortic bifurcation. Intra- and interobserver agreement of aortic volume were calculated by using the intraclass correlation coefficient. Differences in variables were analyzed with the Student t test and logistic regression. Effect size was calculated. Intra- and interobserver agreement of aortic volume calculation was 0.996 and 0.980, respectively. Mean aortic volume was significantly greater in patients with Marfan syndrome than in control subjects (104 mL/m(2); 95% confidence interval [CI]: 95, 114 mL/m(2) vs 74 mL/m(2); 95% CI: 62, 87 mL/m(2); P < .001). In 22 patients with Marfan syndrome, mean aortic volume was increased at 3 years of follow-up (17 mL; 95% CI: 8, 26 mL; P = .001; effect size, 0.29), while mean aortic diameter did not increase significantly (0.4 mm; 95% CI: 0.0, 0.9 mm; P = .171; effect size, 0.13). Assessment of aortic volume is highly reproducible and may be suited for use in the detection of aortic expansion in patients with Marfan syndrome. http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13122310/-/DC1. RSNA, 2013

  8. High pacing rates for management of aortic insufficiency after balloon aortic valvuloplasty or transcatheter aortic valve replacement.

    PubMed

    Ali, Omar; Salinger, Michael H; Levisay, Justin P; Feldman, Ted

    2014-01-01

    Aortic insufficiency (AI) after transcatheter aortic valve replacement (TAVR) is difficult to manage when associated with congestive heart failure. AI after balloon aortic valvuloplasty (BAV) may be catastrophic, especially in patients who are not candidates for TAVR. We describe the use of urgent temporary pacing, followed by permanent pacing, to increase the heart rate to diminish diastolic filling time for the short term management of AI after BAV or TAVR. The strategy is particularly useful in patients who already have permanent pacemakers, which are common in this population.

  9. Long-Term Risk for Aortic Complications After Aortic Valve Replacement in Patients With Bicuspid Aortic Valve Versus Marfan Syndrome.

    PubMed

    Itagaki, Shinobu; Chikwe, Joanna P; Chiang, Yuting P; Egorova, Natalia N; Adams, David H

    2015-06-09

    Bicuspid aortic valves are associated with valve dysfunction, ascending aortic aneurysm and dissection. Management of the ascending aorta at the time of aortic valve replacement (AVR) in these patients is controversial and has been extrapolated from experience with Marfan syndrome, despite the absence of comparative long-term outcome data. This study sought to assess whether the natural history of thoracic aortopathy after AVR in patients with bicuspid aortic valve disease is substantially different from that seen in patients with Marfan syndrome. In this retrospective comparison, outcomes of 13,205 adults (2,079 with bicuspid aortic valves, 73 with Marfan syndrome, and 11,053 control patients with acquired aortic valve disease) who underwent primary AVR without replacement of the ascending aorta in New York State between 1995 and 2010 were compared. The median follow-up time was 6.6 years. The long-term incidence of thoracic aortic dissection was significantly higher in patients with Marfan syndrome (5.5 ± 2.7%) compared with those with bicuspid valves (0.55 ± 0.21%) and control group patients (0.41 ± 0.08%, p < 0.001). Thoracic aortic aneurysms were significantly more likely to be diagnosed in late follow-up in patients with Marfan syndrome (10.8 ± 4.4%) compared with those with bicuspid valves (4.8 ± 0.8%) and control group patients (1.4 ± 0.2%) (p < 0.001). Patients with Marfan syndrome were significantly more likely to undergo thoracic aortic surgery in late follow-up (10.4 ± 4.3%) compared with those with bicuspid valves (2.5 ± 0.6%) and control group patients (0.50 ± 0.09%) (p < 0.001). The much higher long-term rates of aortic complications after AVR observed in patients with Marfan syndrome compared with those with bicuspid aortic valves confirm that operative management of patients with bicuspid aortic valves should not be extrapolated from Marfan syndrome and support discrete treatment algorithms for these different clinical entities

  10. Severe Aortic Coarctation in a 75-Year-Old Woman: Total Simultaneous Repair of Aortic Coarctation and Severe Aortic Stenosis

    PubMed Central

    Park, Ju Hyun; Song, Sung Gook; Kim, Jeong Su; Park, Yong Hyun; Kim, Jun; Choo, Ki Seuk; Kim, June Hong; Lee, Sang Kwon

    2012-01-01

    Aortic coarctation is usually diagnosed and repaired in childhood and early adulthood. Survival of a patient with an uncorrected coarctation to more than 70 years of age is extremely unusual, and management strategies for these cases remain controversial. We present a case of a 75-year-old woman who was first diagnosed with aortic coarctation and severe aortic valve stenosis 5 years ago and who underwent a successful one-stage repair involving valve replacement and insertion of an extra-anatomical bypass graft from the ascending to the descending aorta. PMID:22363387

  11. Experimental evaluation of heat and moisture transfer in metal dog cage environments.

    PubMed

    Woods, J E; Nevins, R G; Besch, E L

    1975-08-01

    Dog cages with solid and expanded metal flooring were tested while unoccupied, occupied by a 10-kg adult male beagle, and occupied by simulated loads to represent a beagle and a greyhound. Cage performances were evaluated with no direct coupling between the room air supply and the cage, and with mechanical coupling of 50% and 100% of the room air supplied directly to the cage. At each of these conditions, the room was maintained at approximately 24 degrees C and 45% relative humidity with room air exchange rates of 5, 10, and 15 changes per hr. Results indicated significant differences existed in dry-bulb and dew-point temperatures between the cage and the room. These differences, together with significant vertical gradients of air velocity and dry-bulb and dew-point temperatures within the cage were shown to be affected by room air exchange rate, cage flooring, type of coupling, and cage load.

  12. The effects of cage enrichment on agonistic behaviour and dominance in male laboratory rats (Rattus norvegicus).

    PubMed

    Abou-Ismail, Usama A

    2011-04-01

    This experiment was carried out to investigate the effects of enriching laboratory cages on agonistic interaction and dominance of rats. In a series of three replicates, 48 rats were housed in groups of four in either 'standard' or 'enriched' cages for 6 weeks. Successful aggressive and defensive behaviour that ended up in a clear winner and loser were sampled in the first hour of the dark phase of the light/dark cycle every other week. Rats in the 'complex' cages showed lower levels of both successful aggressive and successful defensive bouts compared to rats in the 'standard' cages. Enriching cages of laboratory rat did not change the social order of the animals in the cage. Thus, enhancing the complexity of cages of laboratory rats by the particular cage modification regimen implemented in this experiment could be considered enrichment and could therefore result in an improvement of welfare in these animals.

  13. Effects of simple and disposable chicken cages for experimental Eimeria infections.

    PubMed

    Yoo, Jeongmi; Kang, Sung H; Jeong, Jipseol; Kim, Woo H; Kim, Suk; Lillehoj, Hyun S; Min, Wongi

    2011-09-01

    During experimental Eimeria infections in chickens, facilities are often contaminated by fecal oocysts known to be highly resistant to both chemical and enzymatic treatments. Thus, studies using experimental Eimeria infections have been limited due to the difficulty of complete elimination of residual oocysts from both cages and facilities. To overcome this limitation, simple, inexpensive, and disposable cages were constructed from cardboard boxes and tested during experimental Eimeria maxima infections. The cages were used in animal rooms with only a 1.7% evidence of coccidia contamination between adjacent cages. No significant differences in fecal oocyst output and body weight gain were noted between animals housed in disposable cages and animals housed in wire control cages. This cage design is a useful means for preventing oocyst contamination during experimental conditions, suggesting that this disposable cage design could be used for other avian infectious disease studies.

  14. Comparison of eggshell hygiene in two housing systems: standard and furnished cages.

    PubMed

    Mallet, S; Guesdon, V; Ahmed, A M H; Nys, Y

    2006-02-01

    1. The hygienic properties of eggs produced in two designs of furnished cage were investigated and compared to two standard cage designs. 2. At 28, 37, 47 and 58 weeks of age, the proportion of dirty eggs was higher in one of the furnished cage designs while, in the other, it was similar to standard cages. 3. At 27, 33 and 60 weeks, the bacterial load on the eggshell (total aerobic bacteria and enterococci) was higher in furnished cage designs. A seasonal effect was observed with lower counts at 60 weeks (winter) than at 27 weeks (summer). 4. More dirty eggs and a higher bacterial load were observed in eggs laid outside the nests, which suggests egg hygiene in furnished cages could be similar to standard cages if the equipment in furnished cages was improved to enhance nest laying.

  15. 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.

  16. Whole-tree canopy enclosures: why cage a tree?

    Treesearch

    Jerome F. Grant; Abdul Hakeem; Paris L. Lambdin; Gregory J. Wiggins; Rusty J. Rhea

    2011-01-01

    The use of whole-tree canopy enclosures (i.e., cages) is not a typical approach to assessing biological parameters and interactions in a forest setting. However, the successful application of this technology may enable researchers to better understand certain types of tree/organismal interactions.

  17. 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

  18. FANTOM5 CAGE profiles of human and mouse samples.

    PubMed

    Noguchi, Shuhei; Arakawa, Takahiro; Fukuda, Shiro; Furuno, Masaaki; Hasegawa, Akira; Hori, Fumi; Ishikawa-Kato, Sachi; Kaida, Kaoru; Kaiho, Ai; Kanamori-Katayama, Mutsumi; Kawashima, Tsugumi; Kojima, Miki; Kubosaki, Atsutaka; Manabe, Ri-Ichiroh; Murata, Mitsuyoshi; Nagao-Sato, Sayaka; Nakazato, Kenichi; Ninomiya, Noriko; Nishiyori-Sueki, Hiromi; Noma, Shohei; Saijyo, Eri; Saka, Akiko; Sakai, Mizuho; Simon, Christophe; Suzuki, Naoko; Tagami, Michihira; Watanabe, Shoko; Yoshida, Shigehiro; Arner, Peter; Axton, Richard A; Babina, Magda; Baillie, J Kenneth; Barnett, Timothy C; Beckhouse, Anthony G; Blumenthal, Antje; Bodega, Beatrice; Bonetti, Alessandro; Briggs, James; Brombacher, Frank; Carlisle, Ailsa J; Clevers, Hans C; Davis, Carrie A; Detmar, Michael; Dohi, Taeko; Edge, Albert S B; Edinger, Matthias; Ehrlund, Anna; Ekwall, Karl; Endoh, Mitsuhiro; Enomoto, Hideki; Eslami, Afsaneh; Fagiolini, Michela; Fairbairn, Lynsey; Farach-Carson, Mary C; Faulkner, Geoffrey J; Ferrai, Carmelo; Fisher, Malcolm E; Forrester, Lesley M; Fujita, Rie; Furusawa, Jun-Ichi; Geijtenbeek, Teunis B; Gingeras, Thomas; Goldowitz, Daniel; Guhl, Sven; Guler, Reto; Gustincich, Stefano; Ha, Thomas J; Hamaguchi, Masahide; Hara, Mitsuko; Hasegawa, Yuki; Herlyn, Meenhard; Heutink, Peter; Hitchens, Kelly J; Hume, David A; Ikawa, Tomokatsu; Ishizu, Yuri; Kai, Chieko; Kawamoto, Hiroshi; Kawamura, Yuki I; Kempfle, Judith S; Kenna, Tony J; Kere, Juha; Khachigian, Levon M; Kitamura, Toshio; Klein, Sarah; Klinken, S Peter; Knox, Alan J; Kojima, Soichi; Koseki, Haruhiko; Koyasu, Shigeo; Lee, Weonju; Lennartsson, Andreas; Mackay-Sim, Alan; Mejhert, Niklas; Mizuno, Yosuke; Morikawa, Hiromasa; Morimoto, Mitsuru; Moro, Kazuyo; Morris, Kelly J; Motohashi, Hozumi; Mummery, Christine L; Nakachi, Yutaka; Nakahara, Fumio; Nakamura, Toshiyuki; Nakamura, Yukio; Nozaki, Tadasuke; Ogishima, Soichi; Ohkura, Naganari; Ohno, Hiroshi; Ohshima, Mitsuhiro; Okada-Hatakeyama, Mariko; Okazaki, Yasushi; Orlando, Valerio; Ovchinnikov, Dmitry A; Passier, Robert; Patrikakis, Margaret; Pombo, Ana; Pradhan-Bhatt, Swati; Qin, Xian-Yang; Rehli, Michael; Rizzu, Patrizia; Roy, Sugata; Sajantila, Antti; Sakaguchi, Shimon; Sato, Hiroki; Satoh, Hironori; Savvi, Suzana; Saxena, Alka; Schmidl, Christian; Schneider, Claudio; Schulze-Tanzil, Gundula G; Schwegmann, Anita; Sheng, Guojun; Shin, Jay W; Sugiyama, Daisuke; Sugiyama, Takaaki; Summers, Kim M; Takahashi, Naoko; Takai, Jun; Tanaka, Hiroshi; Tatsukawa, Hideki; Tomoiu, Andru; Toyoda, Hiroo; van de Wetering, Marc; van den Berg, Linda M; Verardo, Roberto; Vijayan, Dipti; Wells, Christine A; Winteringham, Louise N; Wolvetang, Ernst; Yamaguchi, Yoko; Yamamoto, Masayuki; Yanagi-Mizuochi, Chiyo; Yoneda, Misako; Yonekura, Yohei; Zhang, Peter G; Zucchelli, Silvia; Abugessaisa, Imad; Arner, Erik; Harshbarger, Jayson; Kondo, Atsushi; Lassmann, Timo; Lizio, Marina; Sahin, Serkan; Sengstag, Thierry; Severin, Jessica; Shimoji, Hisashi; Suzuki, Masanori; Suzuki, Harukazu; Kawai, Jun; Kondo, Naoto; Itoh, Masayoshi; Daub, Carsten O; Kasukawa, Takeya; Kawaji, Hideya; Carninci, Piero; Forrest, Alistair R R; Hayashizaki, Yoshihide

    2017-08-29

    In the FANTOM5 project, transcription initiation events across the human and mouse genomes were mapped at a single base-pair resolution and their frequencies were monitored by CAGE (Cap Analysis of Gene Expression) coupled with single-molecule sequencing. Approximately three thousands of samples, consisting of a variety of primary cells, tissues, cell lines, and time series samples during cell activation and development, were subjected to a uniform pipeline of CAGE data production. The analysis pipeline started by measuring RNA extracts to assess their quality, and continued to CAGE library production by using a robotic or a manual workflow, single molecule sequencing, and computational processing to generate frequencies of transcription initiation. Resulting data represents the consequence of transcriptional regulation in each analyzed state of mammalian cells. Non-overlapping peaks over the CAGE profiles, approximately 200,000 and 150,000 peaks for the human and mouse genomes, were identified and annotated to provide precise location of known promoters as well as novel ones, and to quantify their activities.

  19. 48 CFR 204.7202-1 - CAGE codes.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Logistics Information Service assigns or records and maintains CAGE codes to identify commercial and Government entities. DoD 4000.25-5-M, Military Standard Contract Administration Procedures (MILSCAP), and Volume 7 of DoD 4100.39-M, Federal Logistics Information System (FLIS) Procedures Manual, prescribe use...

  20. 48 CFR 204.7202-1 - CAGE codes.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Logistics Information Service assigns or records and maintains CAGE codes to identify commercial and Government entities. DoD 4000.25-5-M, Military Standard Contract Administration Procedures (MILSCAP), and Volume 7 of DoD 4100.39-M, Federal Logistics Information System (FLIS) Procedures Manual, prescribe use...

  1. Three-dimensional protonic conductivity in porous organic cage solids

    NASA Astrophysics Data System (ADS)

    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.

    2016-09-01

    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.

  2. 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

    2016-09-13

    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.

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

    PubMed Central

    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.

    2016-01-01

    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

  4. 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.

  5. Dynamic Folding Pathway Models of the Trp-Cage Protein

    PubMed Central

    Kim, Seung-Yeon

    2013-01-01

    Using action-derived molecular dynamics (ADMD), we study the dynamic folding pathway models of the Trp-cage protein by providing its sequential conformational changes from its initial disordered structure to the final native structure at atomic details. We find that the numbers of native contacts and native hydrogen bonds are highly correlated, implying that the native structure of Trp-cage is achieved through the concurrent formations of native contacts and native hydrogen bonds. In early stage, an unfolded state appears with partially formed native contacts (~40%) and native hydrogen bonds (~30%). Afterward, the folding is initiated by the contact of the side chain of Tyr3 with that of Trp6, together with the formation of the N-terminal α-helix. Then, the C-terminal polyproline structure docks onto the Trp6 and Tyr3 rings, resulting in the formations of the hydrophobic core of Trp-cage and its near-native state. Finally, the slow adjustment processes of the near-native states into the native structure are dominant in later stage. The ADMD results are in agreement with those of the experimental folding studies on Trp-cage and consistent with most of other computational studies. PMID:23865078

  6. 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...

  7. Synthesis of a photo-caged aminooxy alkane thiol.

    PubMed

    Mancini, Rock J; Li, Ronald C; Tolstyka, Zachary P; Maynard, Heather D

    2009-12-07

    A photo-caged aminooxy alkane thiol synthesized in 7 steps and 15% overall yield was used to form a self-assembled monolayer (SAM). Photo-deprotection on the surface was confirmed by FT-IR spectroscopy and contact angle goniometry. Conjugation of a small molecule ketone, ethyl levulinate, further confirmed the presence of aminooxy groups on the surface.

  8. Pathogen Prevalence From Traditional Cage and Free Range Production

    USDA-ARS?s Scientific Manuscript database

    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...

  9. Xen clusters in the alpha cages of zeolite KA

    NASA Astrophysics Data System (ADS)

    Jameson, Cynthia J.; Jameson, A. Keith; Gerald, Rex E., II; Lim, Hyung-Mi

    1995-11-01

    We have observed the individual signals of the Xen clusters (n=1-5) trapped in the alpha cages of zeolite KA. The 129Xe NMR chemical shift of each cluster in zeolite KA is larger than that of the corresponding Xen cluster in zeolite NaA. The temperature dependence of the chemical shifts of the clusters vary systematically with cluster size as they do in NaA, but the change of the temperature coefficients with n is somewhat more pronounced for Xen in the cages of KA than in NaA. The Xen chemical shifts and their variation with temperature are reproduced by the grand canonical Monte Carlo (GCMC) simulations. GCMC simulations of the distribution of the Xe atoms among the alpha cages in KA provide the fractions of cages containing n Xe atoms which agree reasonably well with the observed equilibrium distributions. The characteristics of Xe distribution and chemical shifts in KA are compared with that in NaA.

  10. CO cage recombination in hemoglobin : Picosecond photolysis and nanosecond observation

    NASA Astrophysics Data System (ADS)

    Pin, S.; Valat, P.; Tourbez, H.; Alpert, B.

    1986-07-01

    Carboxy hemoglobin in aqueous solution was photodissociated by laser pulses of 30 ps at 532 nm. Kinetic studies show that only upon complete photodissociation can the pure CO geminate binding process be revealed. The protein region of the iron cage, where the geminate ligand diffuses before reaching the heme, is smaller than a single subunit and larger than the heme pocket.

  11. 48 CFR 204.7202-1 - CAGE codes.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CD ROM that contains the H-4/H-8 CAGE master file issued by DLIS (Their address is: Customer Service... assignments to DLIS Customer Service: toll-free (888) 227-2423 or (888) 352-9333; DSN 932-4725; or commercial...

  12. 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

    2016-08-02

    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.

  13. A novel method of anterior lumbosacral cage reconstruction.

    PubMed

    Mathios, Dimitrios; Kaloostian, Paul Edward; Bydon, Ali; Sciubba, Daniel M; Wolinsky, Jean Paul; Gokaslan, Ziya L; Witham, Timothy F

    2014-02-01

    Reconstruction of the lumbosacral junction is a considerable challenge for spinal surgeons due to the unique anatomical constraints of this region as well as the vectors of force that are applied focally in this area. The standard cages, both expandable and nonexpendable, often fail to reconstitute the appropriate anatomical alignment of the lumbosacral junction. This inadequate reconstruction may predispose the patient to continued back pain and neurological symptoms as well as possible pseudarthrosis and instrumentation failure. The authors describe their preoperative planning and the technical characteristics of their novel reconstruction technique at the lumbosacral junction using a cage with adjustable caps. Based precisely on preoperative measurements that maintain the appropriate Cobb angle, they performed reconstruction of the lumbosacral junction in a series of 3 patients. All 3 patients had excellent installation of the cages used for reconstruction. Postoperative CT scans were used to radiographically confirm the appropriate reconstruction of the lumbosacral junction. All patients had a significant reduction in pain, had neurological improvement, and experienced no instrumentation failure at the time of latest follow-up. Taking into account the inherent morphology of the lumbosacral junction and carefully planning the technical characteristics of the cage installation preoperatively and intraoperatively, the authors achieved favorable clinical and radiographic outcomes in all 3 cases. Based on this small case series, this technique for reconstruction of the lumbosacral junction appears to be a safe and appropriate method of reconstruction of the anterior spinal column in this technically challenging region of the spine.

  14. A cage-monoterpene indole alkaloid from Alstonia scholaris.

    PubMed

    Cai, Xiang-Hai; Tan, Qin-Gang; Liu, Ya-Ping; Feng, Tao; Du, Zhi-Zhi; Li, Wei-Qi; Luo, Xiao-Dong

    2008-02-21

    An unprecedented cage-like alkaloid, scholarisine A was isolated from the leaves of Alstonia scholaris and its structure determined on the basis of 1D and 2D NMR, FTIR, UV, and high-resolution mass spectroscopic data. This alkaloid might be derived from picrinine via oxygenation, rearrangement, and lactonization.

  15. FANTOM5 CAGE profiles of human and mouse samples

    PubMed Central

    Noguchi, Shuhei; Arakawa, Takahiro; Fukuda, Shiro; Furuno, Masaaki; Hasegawa, Akira; Hori, Fumi; Ishikawa-Kato, Sachi; Kaida, Kaoru; Kaiho, Ai; Kanamori-Katayama, Mutsumi; Kawashima, Tsugumi; Kojima, Miki; Kubosaki, Atsutaka; Manabe, Ri-ichiroh; Murata, Mitsuyoshi; Nagao-Sato, Sayaka; Nakazato, Kenichi; Ninomiya, Noriko; Nishiyori-Sueki, Hiromi; Noma, Shohei; Saijyo, Eri; Saka, Akiko; Sakai, Mizuho; Simon, Christophe; Suzuki, Naoko; Tagami, Michihira; Watanabe, Shoko; Yoshida, Shigehiro; Arner, Peter; Axton, Richard A.; Babina, Magda; Baillie, J. Kenneth; Barnett, Timothy C.; Beckhouse, Anthony G.; Blumenthal, Antje; Bodega, Beatrice; Bonetti, Alessandro; Briggs, James; Brombacher, Frank; Carlisle, Ailsa J.; Clevers, Hans C.; Davis, Carrie A.; Detmar, Michael; Dohi, Taeko; Edge, Albert S.B.; Edinger, Matthias; Ehrlund, Anna; Ekwall, Karl; Endoh, Mitsuhiro; Enomoto, Hideki; Eslami, Afsaneh; Fagiolini, Michela; Fairbairn, Lynsey; Farach-Carson, Mary C.; Faulkner, Geoffrey J.; Ferrai, Carmelo; Fisher, Malcolm E.; Forrester, Lesley M.; Fujita, Rie; Furusawa, Jun-ichi; Geijtenbeek, Teunis B.; Gingeras, Thomas; Goldowitz, Daniel; Guhl, Sven; Guler, Reto; Gustincich, Stefano; Ha, Thomas J.; Hamaguchi, Masahide; Hara, Mitsuko; Hasegawa, Yuki; Herlyn, Meenhard; Heutink, Peter; Hitchens, Kelly J.; Hume, David A.; Ikawa, Tomokatsu; Ishizu, Yuri; Kai, Chieko; Kawamoto, Hiroshi; Kawamura, Yuki I.; Kempfle, Judith S.; Kenna, Tony J.; Kere, Juha; Khachigian, Levon M.; Kitamura, Toshio; Klein, Sarah; Klinken, S. Peter; Knox, Alan J.; Kojima, Soichi; Koseki, Haruhiko; Koyasu, Shigeo; Lee, Weonju; Lennartsson, Andreas; Mackay-sim, Alan; Mejhert, Niklas; Mizuno, Yosuke; Morikawa, Hiromasa; Morimoto, Mitsuru; Moro, Kazuyo; Morris, Kelly J.; Motohashi, Hozumi; Mummery, Christine L.; Nakachi, Yutaka; Nakahara, Fumio; Nakamura, Toshiyuki; Nakamura, Yukio; Nozaki, Tadasuke; Ogishima, Soichi; Ohkura, Naganari; Ohno, Hiroshi; Ohshima, Mitsuhiro; Okada-Hatakeyama, Mariko; Okazaki, Yasushi; Orlando, Valerio; Ovchinnikov, Dmitry A.; Passier, Robert; Patrikakis, Margaret; Pombo, Ana; Pradhan-Bhatt, Swati; Qin, Xian-Yang; Rehli, Michael; Rizzu, Patrizia; Roy, Sugata; Sajantila, Antti; Sakaguchi, Shimon; Sato, Hiroki; Satoh, Hironori; Savvi, Suzana; Saxena, Alka; Schmidl, Christian; Schneider, Claudio; Schulze-Tanzil, Gundula G.; Schwegmann, Anita; Sheng, Guojun; Shin, Jay W.; Sugiyama, Daisuke; Sugiyama, Takaaki; Summers, Kim M.; Takahashi, Naoko; Takai, Jun; Tanaka, Hiroshi; Tatsukawa, Hideki; Tomoiu, Andru; Toyoda, Hiroo; van de Wetering, Marc; van den Berg, Linda M.; Verardo, Roberto; Vijayan, Dipti; Wells, Christine A.; Winteringham, Louise N.; Wolvetang, Ernst; Yamaguchi, Yoko; Yamamoto, Masayuki; Yanagi-Mizuochi, Chiyo; Yoneda, Misako; Yonekura, Yohei; Zhang, Peter G.; Zucchelli, Silvia; Abugessaisa, Imad; Arner, Erik; Harshbarger, Jayson; Kondo, Atsushi; Lassmann, Timo; Lizio, Marina; Sahin, Serkan; Sengstag, Thierry; Severin, Jessica; Shimoji, Hisashi; Suzuki, Masanori; Suzuki, Harukazu; Kawai, Jun; Kondo, Naoto; Itoh, Masayoshi; Daub, Carsten O.; Kasukawa, Takeya; Kawaji, Hideya; Carninci, Piero; Forrest, Alistair R.R.; Hayashizaki, Yoshihide

    2017-01-01

    In the FANTOM5 project, transcription initiation events across the human and mouse genomes were mapped at a single base-pair resolution and their frequencies were monitored by CAGE (Cap Analysis of Gene Expression) coupled with single-molecule sequencing. Approximately three thousands of samples, consisting of a variety of primary cells, tissues, cell lines, and time series samples during cell activation and development, were subjected to a uniform pipeline of CAGE data production. The analysis pipeline started by measuring RNA extracts to assess their quality, and continued to CAGE library production by using a robotic or a manual workflow, single molecule sequencing, and computational processing to generate frequencies of transcription initiation. Resulting data represents the consequence of transcriptional regulation in each analyzed state of mammalian cells. Non-overlapping peaks over the CAGE profiles, approximately 200,000 and 150,000 peaks for the human and mouse genomes, were identified and annotated to provide precise location of known promoters as well as novel ones, and to quantify their activities. PMID:28850106

  16. Assessment of density in enriched colony cages: Egg quality

    USDA-ARS?s Scientific Manuscript database

    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...

  17. Isomer Stability of N6C6H6 Cages

    PubMed Central

    Strout, Douglas L.

    2008-01-01

    Recent theoretical studies have identified carbon-nitrogen cages that are potentially stable high energy density materials (HEDM). One such molecule is an N6C6H6 cage in which a six-membered ring of nitrogen is bonded to C3H3 triangles on both sides. This molecule is based on the structure of the most stable N12 cage, with six carbon atoms substituted into the structure. In the current study, several N6C6H6 isomers (including the previously studied cage) are examined by theoretical calculations to determine which is actually the most stable. Stability will be evaluated from two points of view: (1) thermodynamic stability of one isomer versus another, and (2) kinetic stability of each isomer as determined by the energetics of bond breaking. Density functional theory (B3LYP), perturbation theory (MP2 and MP4), and coupled-cluster theory (CCSD(T)) are used in this study, along with the correlation-consistent basis sets of Dunning. Trends in thermodynamic and kinetic stability are discussed. PMID:16737273

  18. Three-dimensional protonic conductivity in porous organic cage solids

    PubMed Central

    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

  19. 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...

  20. Genotoxicity monitoring of freshwater environments using caged crayfish (Astacus leptodactylus).

    PubMed

    Klobučar, Göran I V; Malev, Olga; Šrut, Maja; Štambuk, Anamaria; Lorenzon, Simonetta; Cvetković, Želimira; Ferrero, Enrico A; Maguire, Ivana

    2012-03-01

    Genotoxicity of freshwater pollution was assessed by measuring DNA damage in haemocytes of caged freshwater crayfish Astacus leptodactylus by the means of Comet assay and micronucleus test, integrated with the measurements of physiological (total protein concentration) and immunological (total haemocyte count) haemolymph parameters as biomarkers of undergone stress. Crayfish were collected at the reference site (River Mrežnica) and exposed in cages for 1 week at three polluted sites along the Sava River (Zagreb, Sisak, Krapje). The long term pollution status of these locations was confirmed by chemical analyses of sediments. Statistically significant increase in DNA damage measured by the Comet assay was observed at all three polluted sites comparing to the crayfish from reference site. In addition, native crayfish from the mildly polluted site (Krapje) cage-exposed on another polluted site (Zagreb) showed lower DNA damage than crayfish from the reference site exposed at the same location indicating adaptation and acclimatisation of crayfish to lower levels of pollution. Micronuclei induction showed similar gradient of DNA damage as Comet assay, but did not reach the statistical significance. Observed increase in total haemocyte count and total protein content in crayfish from polluted environments in the Sava River also confirmed stress caused by exposure to pollution. The results of this study have proved the applicability of caging exposure of freshwater crayfish A. leptodactylus in environmental genotoxicity monitoring using Comet assay and micronucleus test.

  1. 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.

  2. Lipedema is associated with increased aortic stiffness.

    PubMed

    Szolnoky, G; Nemes, A; Gavallér, H; Forster, T; Kemény, L

    2012-06-01

    Lipedema is a disproportional obesity due to unknown pathomechanism. Its major hallmark is frequent hematoma formation related to increased capillary fragility and reduced venoarterial reflex. Beyond microangiopathy, both venous and lymphatic dysfunction have also been documented. However, arterial circulation in lipedema has not been examined, and therefore we explored aortic elastic properties by echocardiography. Fourteen women with and 14 without lipedema were included in the study. Each subject consented to blood pressure measurement, physical examination, and transthoracic echocardiography. Aortic stiffness index (beta), distensibility, and strain were evaluated from aortic diameter and blood pressure data. Mean systolic (30.0 +/- 3.2 vs. 25.5 +/- 3.6, P < 0.05) and diastolic (27.8 +/- 3.3 vs. 22.3 +/- 3.1) aortic diameters (in mm) and aortic stiffness index (9.05 +/- 7.45 vs. 3.76 +/- 1.22, P < 0.05) were significantly higher, while aortic strain (0.082 +/- 0.04 vs. 0.143 +/- 0.038, P < 0.05) and distensibility (2.24 +/- 1.07 vs. 4.38 +/- 1.61, P < 0.05) were significantly lower in lipedematous patients compared to controls. Thus, lipedema is characterized with increased aortic stiffness.

  3. Repair for acquired aortic valve disease.

    PubMed

    Antunes, M J

    1996-10-01

    The favorable results of mitral valvuloplasty when compared with valve replacement have renewed the interest of many surgeons in aortic valve repair. However, these efforts have, for the most part, been unsuccessful. Also, the results of aortic valve replacement are usually better than those of mitral valve replacement. Yet, some patients appear to derive benefit from a conservative aortic valve procedure. The best examples are mild or moderate aortic valve disease associated with mitral valve or coronary artery disease, which constitute the primary indication for operation, where "prophylactic" aortic valve replacement does not appear justifiable. Other possible indications for aortic valvuloplasty includes patient's lack of compliance or contraindication to anticoagulation in young patients. Senile aortic stenosis, in very old patients with a small annulus, preserved leaflet morphology and nonsignificant commissural fusion should be considered for repair. However, since the procedure is not easily reproducible and the results not uniformly predictable, it cannot be recommended for generalized use. Nonetheless, experienced surgeons should be encouraged to continue these efforts.

  4. 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

  5. Medical management of thoracic aortic aneurysm disease.

    PubMed

    Braverman, Alan C

    2013-03-01

    The patient with thoracic aortic aneurysm disease requires careful evaluation and management over his or her lifetime. This includes assessment for the presence of an underlying genetic disorder, such as Marfan syndrome, bicuspid aortic valve disease, or a familial aortic aneurysm syndrome. Screening family members is necessary, inasmuch as up to 20% of first-degree relatives of the patient with a thoracic aortic aneurysm will also have aneurysm disease. Medical therapy is often prescribed, and beta-blocker therapy to reduce the stress on the aortic wall is usually recommended. However, very few clinical trials of pharmacologic therapy in humans with thoracic aortic aneurysm disease have been conducted. Mouse models have led to important discoveries and insight into the pathogenesis of aneurysm syndromes, and there is hope these may lead to effective therapy in people. Several studies are ongoing that examine the role of angiotensin receptor blockers in Marfan syndrome. Lifestyle modification is also important for patients with thoracic aortic aneurysm, including restrictions on physical activity, weight lifting, and recommendations about the management of pregnancy. Long-term surveillance of the aorta, even after successful surgery, is necessary for timing of prophylactic surgery and to evaluate for late complications. Copyright © 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  6. Age and Aortic Diameters in Pilots.

    PubMed

    Akın, Ahmet; Ozturk, Cengiz; Aparci, Mustafa; Cakmak, Tolga; Metin, Suleyman; Balta, Sevket; Sen, Ahmet

    2015-12-01

    Pilots are exposed to various physical and hemodynamic stresses during flight. Aortic dilatation may be one of the important consequences of flight-related stress. In this study, we evaluated whether or not variation in aortic diameter was associated with the type of aircraft and the age of pilots. Medical records of 87 jet aircraft pilots (JP) (mean age = 30.0 ± 7.0 years) and 65 non-jet aircraft pilots (NJP) (mean age = 32.63 ± 5.7) were reviewed. Echocardiographic diameters of the aortic sinus (AoS) and ascending aorta (AoAsc) were measured using standard echo probe positions. Aortic diameters were not statistically different between JP and NJP. Regression analysis revealed that the diameters of the AoS (R = 0.484, R(2) = 0.234, p < 0.001) and AoAsc (R = 0.514, R(2) = 0.264, p < 0.001) were significantly associated with age in the JP group. Whereas, there was not any relationship found between age and the diameters of the AoS and AoAsc in the NJP group. Jet pilots had aortic enlargement as they became older in contrast to the NJP group. Although the aortic diameters were not within the critical ranges in the JP group, these results could suggest that flight-related stresses might result in acute aortic syndromes in the long term. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

  7. Neonatal aortic thrombosis: a comprehensive review.

    PubMed

    Nagel, K; Tuckuviene, R; Paes, B; Chan, A K

    2010-05-01

    Neonatal aortic thrombosis is a rare occurrence, but can be fatal. Treatment of this condition is hampered by the lack of large studies involving this pediatric population. Reporting of this condition is also not standardized. The purpose of this review is to collate available literature on the incidence, risk factors, presentation, treatment and outcome of neonatal aortic thrombosis as well as suggest a treatment model. A Medline search of PubMed, OVID and Cochrane databases was undertaken using the key words "neonatal", "infant", "aorta", "aortic", "thrombosis", "thrombus" and "clot". Limits were set for articles that were English language only and published between 1980 and September 2009. Following review of all articles using predetermined search words and criteria, 38 were found with sufficient data for our purpose. The reported total number of neonatal patients with aortic thrombosis was 148 and 78% of the aortic thromboses in this review were related to arterial umbilical catheterization. We have suggested a classification system to standardize reporting of neonatal aortic thrombosis, as well as a treatment decision tree, and a clinical guide for the treatment of thrombosis in children. As always, clinicians should balance the risks and benefits of their decision to treat with the level of local expertise. This guide may specifically serve the neonatal population with line-related aortic thrombosis.

  8. Radiological outcomes of static vs expandable titanium cages after corpectomy: a retrospective cohort analysis of subsidence.

    PubMed

    Lau, Darryl; Song, Yeohan; Guan, Zhe; La Marca, Frank; Park, Paul

    2013-04-01

    Mesh cages have commonly been used for reconstruction after corpectomy. Recently, expandable cages have become a popular alternative. Regardless of cage type, subsidence is a concern following cage placement. To assess whether subsidence rates differ between static and expandable cages, and identify independent risk factors for subsidence and extent of subsidence when present. A consecutive population of patients who underwent corpectomy between 2006 and 2009 was identified. Subsidence was assessed via x-ray at 1-month and 1-year follow-ups. In addition to cage type, demographic, medical, and cage-related covariates were recorded. Multivariate models were used to assess independent associations with rate, odds, and extent of subsidence. Of 91 patients, 44.0% had expandable cages and 56.0% had static cages. One-month subsidence rate was 36.3%, and the 1-year subsidence rate was 51.6%. Expandable cages were independently associated with higher rates and odds of subsidence in comparison with static cages. Infection, trauma, and footplate-to-vertebral body endplate ratio of less than 0.5 were independent risk factors for subsidence. The presence of prongs on cages and posterior fusion 2 or more levels above and below corpectomy level had lower rates and odds of subsidence. Infection and cage placement in the thoracic or lumbar region had greater extent of subsidence when subsidence was present. Expandable cages had higher rates and risk of subsidence in comparison with static cages. When subsidence was present, expandable cages had greater magnitudes of subsidence. Other factors including footplate-to-vertebral body endplate ratio, prongs, extent of supplemental posterior fusion, spinal region, and diagnosis also impacted subsidence.

  9. Evaluation of Bioabsorbable Multiamino Acid Copolymer/Nanohydroxyapatite/Calcium Sulfate Cage in a Goat Spine Model.

    PubMed

    Ren, Chunpeng; Song, Yueming; Xue, Youdi; Yang, Xi; Zhou, Chunguang

    2017-07-01

    Currently, polylactide is the most popular material used to made bioabsorbable cages but too-quick degradation and osteolysis around the cage have been reported in the literature. This study evaluated the fusion effect, biomechanical stability, and histologic characteristics of a novel bioabsorbable multiamino acid copolymer/nanohydroxyapatite/calcium sulfate (MAACP/n-HA/CS) interbody cage in a goat model of anterior cervical discectomy and fusion. A total of 24 goats underwent C3/C4 discectomy and fusion with 3 groups of intervertebral implants: MAACP/n-HA/CS cage group (n = 8), titanium cage group (n = 8), and autologous tricortical iliac crest bone group (n = 8). Disc space height and lordosis angle were measured pre- and postoperatively and after 4, 12, and 24 weeks. Range of motion (ROM) was evaluated through biomechanical testing. Histologic analysis was performed to evaluate fusion status and to detect any foreign body reactions associated with the bioabsorbable cages. At 12 and 24 weeks, disc space height in MAACP/n-HA/CS cage group was greater than that of titanium cage group and tricortical iliac crest group (P < 0.05). Lordosis angle in MAACP/n-HA/CS cage group and titanium cage group were lower than that of tricortical iliac crest group (P < 0.05). Biomechanical test showed that ROM did not differ significantly between MAACP/n-HA/CS cage group and titanium cage group, whereas the value of ROM in bone graft group was the largest. Histologic evaluation showed a better interbody fusion in the MAACP/n-HA/CS cage group than in the other 2 groups. MAACP/n-HA/CS cage surface degraded and was absorbed at 24 weeks. All MAACP/n-HA/CS cages showed excellent biocompatibility. MAACP/n-HA/CS cages can provide good fusion effect, enough biomechanical stability, and integrate closely with the surrounding bone. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Concealed primary aortic sarcoma induced hypertensive encephalopathy resulting from a thoracic aortic occlusion: a case report.

    PubMed

    Choi, Hyunmin; Yoon, Hee-Jeoung; Jang, Woo-Ik; Kim, Chang-Young; Doh, Joon-Hyung

    2013-04-18

    Primary aortic sarcoma is a rare condition that is frequently associated with distal embolization. In addition, growth characteristics of primary aortic sarcoma lead to the narrowing of the involved aortic lumen. A 72-year-old Korean male with primary aortic sarcoma showed progressive unexplained blood pressure elevation that didn't improve with additional antihypertensive drug therapy. Because follow-up measures were not taken, the patient ultimately developed hypertensive encephalopathy with concurrent embolic dissemination. Although we successfully performed open transcatheter embolectomy in both legs, the patient died because of multiple organ failure 3 days after surgery. Given the ominous prognosis for this condition, this case report highlights the fact that the value of early detection and prompt evaluation of altered vital signs should not be overemphasized. We describe a rare case of primary aortic sarcoma that showed hypertensive encephalopathy caused by thoracic aortic occlusion and also had embolic metastases to the lower extremities.

  11. Left coronary ostial obstruction after aortic valve replacement with a supra-annular aortic valve.

    PubMed

    Matsuzaki, Kanji; Unno, Hideya; Konishi, Taisuke; Shigeta, Osamu

    2006-05-01

    We report a rare case of left coronary ostial obstruction after aortic valve replacement with a Top Hat supra-annular aortic valve, which was diagnosed with intraoperative transesophageal echocardiography and successfully treated with an unplanned coronary bypass. The patient was a 76-year-old woman (height 143 cm, weight 44 kg) with aortic stenosis and regurgitation. A 19-mm Top Hat valve was implanted in the supra-annular position because of a small aortic annulus. There was a possibility that the high profile of this prosthesis might block the left coronary ostium. There may be a problem with the use of this prosthesis in patients with small and rigid aortic roots with little compliance. Although the Top Hat valve has a great advantage for small aortic annuli, care in its use should be taken due to possible interference with the coronary ostia.

  12. 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

  13. 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.

  14. A cell attracting composite of lumbar fusion cage.

    PubMed

    Gunay, Busra; Hasirci, Nesrin; Hasirci, Vasif

    2017-06-01

    Lumbar fusion cages are devices used in spinal fusion procedures for disorders such as spondylosis and degenerative disc diseases that may occur due to age, trauma or genetic reasons. These devices are most frequently made of metals and polymers. The mechanical properties of such devices should be comparable to the bone to avoid stress shielding. Besides, cages should interact with the cells to prevent extrusion and achieve satisfactory fusion. In this study, poly(methylmethacrylate) (PMMA) and hydroxyapatite (HAp) were compounded to create products with HAp contents up to 40% (w/w), processed by hot melt extrusion and injection molded to produce composites with maximum polymer-mineral interaction. The morphology, interaction with the plates and rate of proliferation of human osteoblast-like (HOB) cells were studied in vitro. We learned that cells interact more with HAp when the HAp content is higher than 20%. Tensile and compressive properties of PMMA were significantly increased with increasing HAp content; from an elastic modulus (E) of 2.08 to 3.92 GPa in tension, and from 349 to 562 MPa in compression. High HAp content of the samples increased the roughness from 0.69 μm for pure PMMA to 1.35 μm for 40% (w/w) HAp loaded PMMA, increased cell proliferation and as a result the cells presented filopodia indicating a satisfactory level of interaction with the cage surface. Based on mechanical and in vitro studies, a HAp content of around 30% (w/w) was found to be appropriate for good cell adhesion and satisfactory mechanical properties for use in the construction of a fusion cage. It was concluded that when PMMA and HAp were compounded at an optimal value, a cage material with adequate mechanical properties and increased cell attachment can be obtained for use in spinal fusion applications.

  15. 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.

  16. 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.

  17. CT diagnosis of ruptured abdominal aortic aneurysm

    SciTech Connect

    Rosen, A.; Korobkin, M.; Silverman, P.M.; Moore, A.V. Jr.; Dunnick, N.R.

    1984-08-01

    Abdominal computed tomography was performed in six patients with suspected ruptured abdominal aortic aneurysm but in whom an alternate clinical diagnosis was seriously considered. In each patient, a large aortic aneurysm was demonstrated in association with a retroperitoneal accumulation of high-density blood. The retroperitoneal blood was primarily confined to the extracapsular perinephric space. In four of the six patients, a focal area of the aortic wall was indistinct on the side of the retroperitoneal hemorrhage at the presumed site of rupture. Five of the six patients underwent emergency surgery, which confirmed the site of aneurysm, presence of rupture and the location of fresh retroperitoneal blood.

  18. Bacillus cereus endocarditis in native aortic valve.

    PubMed

    Ngow, H A; Wan Khairina, W M N

    2013-02-01

    Bacillus cereus endocarditis is rare. It has been implicated in immunocompromised individuals, especially in intravenous drug users as well as in those with a cardiac prosthesis. The patient was a 31-year-old ex-intravenous drug addict with a past history of staphylococcal pulmonary valve endocarditis, who presented with symptoms of decompensated cardiac failure. Echocardiography showed severe aortic regurgitation with an oscillating vegetation seen on the right coronary cusp of the aortic valve. The blood cultures grew Bacillus cereus. We report this as a rare case of Bacillus cereus endocarditis affecting a native aortic valve.

  19. Aortic root abscess presenting as alternating bundle branch block: Infective endocarditis of bicuspid aortic valve

    PubMed Central

    Jain, Rakesh; Kader, Muneer; Sajeev, C.G.; Krishnan, M.N.

    2015-01-01

    Bicuspid aortic valve is the most common congenital cardiac malformation, affecting 1%–2% of the population. Among various complications, incidence of infective endocarditis (IE) in the bicuspid aortic valve population is high with higher rate of periannular extension resulting in conduction disturbances. Here we are reporting a rare case of infective endocarditis of bicuspid aortic valve presented with alternating bundle branch block. PMID:26138186

  20. Structural valve deterioration after aortic valve replacement with Medtronic freestyle stentless porcine aortic root bioprostheses.

    PubMed

    Nishida, Hidefumi; Komiya, Tatsuhiko; Sakaguchi, Genichi; Shimamoto, Takeshi

    2014-01-01

    The Medtronic freestyle aortic root bioprosthesis (Medtronic, Inc., Minneapolis, MN, USA) is a stentless valve with an effective orifice area that is larger than that observed on other bioprostheses. However, there have been sporadic reports of structural valve deterioration (SVD), such as aortic root wall rupture, leaflet tearing, and pseudoaneurysm formation. We report five cases of SVD of freestyle aortic root bioprostheses. © 2013 The Authors. Journal of Cardiac Surgery Published by Wiley Periodicals, Inc.

  1. Acute Type B Aortic Dissection in a Patient with Previous Endovascular Abdominal Aortic Aneurysm Repair

    PubMed Central

    Park, Sung Hun; Rha, Seung-Woon

    2017-01-01

    Endovascular aortic repair (EVAR) was relatively safe, and became a widely performed procedure. If aortic dissection (AD) occurred in patient with previous EVAR, it could cause fatal complications like endograft collapse. Surgical treatment was limited in this situation for comorbidities and complex anatomies. Here we report a rare case of acute type B AD developed following trans-radial coronary intervention in a patient with previous EVAR of abdominal aortic aneurysm, which was treated with thoracic EVAR. PMID:28377913

  2. Simulations of Transcatheter Aortic Valve Implantation – Implications for Aortic Root Rupture

    PubMed Central

    Wang, Qian; Kodali, Susheel; Primiano, Charles; Sun, Wei

    2014-01-01

    Objectives Aortic root rupture is one of the most severe complications of transcatheter aortic valve implantation (TAVI). The mechanism of this adverse event remains mostly unknown. The purpose of this study was to obtain a better understanding of the biomechanical interaction between the tissue and stent for patients with a high risk of aortic rupture. Methods We simulated the stent deployment process of three TAVI patients with high aortic rupture risk using finite element method. The first case was a retrospective analysis of an aortic rupture case, while the other two cases were prospective studies, which ended with one cancelled procedure and one successful TAVI. Simulation results were evaluated for the risk of aortic root rupture, as well as coronary artery occlusion, and paravalvular leak. Results For Case 1, the simulated aortic rupture location was the same as clinical observations. From the simulation results, it can be seen that the large calcified spot on the interior of the left coronary sinus between coronary ostium and the aortic annulus was pushed by the stent, causing the aortic rupture. For Case 2 and Case 3, predicated results from the simulations were presented to the clinicians at pre-procedure meetings; and they were in agreement with clinician’s observations and decisions. Conclusions Our results indicated that the engineering analysis could provide additional information to help clinicians evaluate complicated, high risk aortic rupture cases. Since a systematic study of a large patient cohort of aortic rupture is currently not available (due to the low occurrence rate) to clearly understand underlying rupture mechanisms, case by case engineering analysis is recommended for evaluating patient-specific aortic rupture risk. PMID:24736808

  3. Temporal changes of aortic neck morphology in abdominal aortic aneurysms.

    PubMed

    Propper, Brandon W; Rasmussen, Todd E; Jones, W Tracey; Gifford, Shaun M; Burkhardt, Gabriel E; Clouse, W Darrin

    2010-05-01

    This study characterized temporal changes in the infrarenal aortic aneurysm neck in patients with small, untreated abdominal aortic aneurysms (AAA). Patients with infrarenal AAA who had contrast-enhanced computed tomography (CT) scans separated by >6 months were identified and their images reviewed. Infrarenal neck diameter and length were measured along with aneurysm diameter. Comparisons between the interval CT scans were made and analysis of factors affecting neck changes performed. Sixty patients met inclusion criteria with an imaging interval of 3.8 years (median, 3.4 years; range, 0.75-9.6 years). During the interval, there was an increase in proximal and distal neck diameters of 1.1 mm (SD, 2.2) (0.28 mm/y) and 1.0 mm (SD, 3.0) (0.26 mm/y), respectively. During the same interval, the neck length decreased by 4 mm (SD, 11) (1 mm/y). A neck length of <15 mm was present in 10 patients (17%) at the initial imaging. Four of the remaining 50 patients experienced an interval decrease in neck length to <15 mm, all of whom had initial lengths of 15 to 20 mm. Medications had no association with changes in neck morphology; however, diabetes correlated with a slower rate of neck shortening (P = .001). The natural history of the aneurysm neck is one of expansion and shortening that will not affect most patients under surveillance. Patients with marginal neck lengths (range, 15-20 mm) at the initial imaging are more likely to experience loss of neck length that may negatively affect endovascular suitability. Published by Mosby, Inc.

  4. 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... Entity (CAGE) Code Reporting (AUG 1999) (a) The offeror is requested to enter its CAGE code on its offer... AND CONTRACT CLAUSES Text of Provisions And Clauses 252.204-7001 Commercial and Government...

  5. 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

    2016-04-25

    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.

  6. Analysis of hydrodynamic losses for various types of aortic valves

    NASA Astrophysics Data System (ADS)

    Starobin, I. M.; Lupachev, S. P.; Dolgopolov, R. V.; Zaiko, V. M.; Kas'yanov, V. A.; Mungalov, D. D.; Morov, G. V.

    1985-05-01

    The creation of an automated computer-controlled hydraulic stand made it possible to measure the main hydrodynamic parameters of the flow through the investigated HVP and to determine the coefficients of Eq. (2) of fluid flow in the test chamber of the stand. The coefficients found can serve as a criterion of a comparative assessment of the hydrodynamics of HVPs. An analysis of the coefficients showed that the main contribution to pressure losses across ball and disc valves is made by viscous and convective effects. An analysis of inertial losses confirmed the presence of oscillations of the ball closing elements of the AKCh-3-06 valve around the props of the stroke limiters and made it possible to assess them quantitatively. For leaflet valves the contribution of inertial losses to the total pressure losses is more considerable than in the case of disc and ball valves both in the regime of an increase of power of the output and in the regime of a constant power. The mechanical properties of the material of leaflet valves have an effect on the hydrodynamic characteristics. The advantage of the investigated leaflet valves consists not only in that they have smaller total hydraulic losses compared with the other valves, but also in that they provide a high amplitude of pulsations of the blood stream in the case of insufficient contractility of the heart.

  7. Stent graft implantation in an aortic pseudoaneurysm associated with a fractured Cheatham-Platinum stent in aortic coarctation.

    PubMed

    Kuhelj, Dimitrij; Berden, Pavel; Podnar, Tomaž

    2016-03-01

    We report a case of aortic pseudoaneurysm associated with a fractured bare Cheatham-Platinum stent following stenting for aortic coarctation. These complications were recognised 6 years after the implantation procedure and were successfully managed by percutaneous stent graft implantation. Staged approach for stent dilatation might prevent development of aortic pseudoaneurysms. In addition, careful follow-up is warranted after stenting for aortic coarctation, particularly in patients with recognised aortic wall injury.

  8. Heparin-Induced-Thrombocytopenia Causing Massive Aortic Thrombosis after Ascending Aortic Replacement for Type A Acute Aortic Dissection

    PubMed Central

    Imoto, Kiyotaka; Uchida, Keiji; Isoda, Susumu; Karube, Norihisa; Yasuda, Shota; Masuda, Munetaka

    2016-01-01

    A 77-year-old woman underwent emergency ascending aortic replacement for type A acute aortic dissection. Fifteen days after the operation, she had motor and sensory disturbances in the lower limbs. Computed tomography revealed multiple aortic thrombi and disrupted blood flow in the right external iliac and left common iliac arteries. She underwent an emergency thrombectomy for acute limb ischemia. Because heparin- induced-thrombocytopenia (HIT) was suspected to have caused the multiple aortic thrombi, we postoperatively changed the anticoagulant therapy from heparin to argatroban. Seventeen days after the first operation, gastrointestinal bleeding developed, and the patient died of mesenteric ischemia caused by HIT. Arterial embolization caused by HIT after cardiovascular surgery is a rare, but fatal event. To avoid fatal complications, early diagnosis and early treatment are essential. Use of a scoring system would probably facilitate early diagnosis. PMID:26780951

  9. Patient-prosthesis mismatch: surgical aortic valve replacement versus transcatheter aortic valve replacement in high risk patients with aortic stenosis

    PubMed Central

    Kron, Irving L.

    2016-01-01

    Patient prosthesis mismatch (PPM) can occur when a prosthetic aortic valve has an effective orifice area (EOA) less than that of a native valve. A recent study by Zorn and colleagues evaluated the incidence and significance of PPM in high risk patients with severe aortic stenosis who were randomized to transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR). TAVR is associated with decreased incidence of severe PPM compared to traditional SAVR valves. Severe PPM increases risk for death at 1 year postoperatively in high risk patients. The increased incidence of PPM is largely due to differences in valve design and should encourage development of newer SAVR valves to reduce risk for PPM. In addition more vigorous approaches to root enlargement in small annulus should be performed with SAVR to prevent PPM. PMID:27867654

  10. Patient-prosthesis mismatch: surgical aortic valve replacement versus transcatheter aortic valve replacement in high risk patients with aortic stenosis.

    PubMed

    Ghanta, Ravi K; Kron, Irving L

    2016-10-01

    Patient prosthesis mismatch (PPM) can occur when a prosthetic aortic valve has an effective orifice area (EOA) less than that of a native valve. A recent study by Zorn and colleagues evaluated the incidence and significance of PPM in high risk patients with severe aortic stenosis who were randomized to transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR). TAVR is associated with decreased incidence of severe PPM compared to traditional SAVR valves. Severe PPM increases risk for death at 1 year postoperatively in high risk patients. The increased incidence of PPM is largely due to differences in valve design and should encourage development of newer SAVR valves to reduce risk for PPM. In addition more vigorous approaches to root enlargement in small annulus should be performed with SAVR to prevent PPM.

  11. 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

  12. Subsidence of Cylindrical Cage (AMSLU™ Cage) : Postoperative 1 Year Follow-up of the Cervical Anterior Interbody Fusion

    PubMed Central

    Joung, Young Il; Ko, Yong; Yi, Hyeong Joong; Lee, Seung Ku

    2007-01-01

    Objective There are numerous reports on the primary stabilizing effects of the different cervical cages for cervical radiculopathy. But, little is known about the subsidence which may be clinical problem postoperatively. The goal of this study is to evaluate subsidence of cage and investigate the correlation between radiologic subsidence and clinical outcome. Methods To assess possible subsidence, the authors investigated clinical and radiological results of the one-hundred patients who underwent anterior cervical fusion by using AMSLU™ cage during the period between January 2003 and June 2005. Preoperative and postoperative lateral radiographs were measured for height of intervertebral disc space where cages were placed. Intervertebral disc space was measured by dividing the sum of anterior, posterior, and midpoint interbody distance by 3. Follow-up time was 6 to 12 months. Subsidence was defined as any change in at least one of our parameters of at least 3 mm. Results Subsidence was found in 22 patients (22%). The mean value of subsidence was 2.21 mm, and mean subsidence rate was 22%. There were no cases of the clinical status deterioration during the follow-up period. No posterior or anterior migration was observed. Conclusion The phenomenon of subsidence is seen in substantial number of patients. Nevertheless, clinical and radiological results of the surgery were favorable. An excessive subsidence may result in hardware failure. Endplate preservation may enables us to control subsidence and reduce the number of complications. PMID:19096571

  13. 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

  14. Intra-cage dynamics of molecular hydrogen confined in cages of two different dimensions of clathrate hydrates.

    PubMed

    Russina, Margarita; Kemner, Ewout; Mezei, Ferenc

    2016-06-07

    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.

  15. Can forced hot air quickly dry feces on transport cage flooring and eliminate campylobacter before cage re-use?

    USDA-ARS?s Scientific Manuscript database

    Allowing feces left on transport coops to dry is an effective way to reduce numbers of viable Campylobacter left by positive flocks. The problem with this approach is that poultry processors do not have the time, space or resources to maintain several times the minimum number of transport cages that...

  16. Management of concomitant large aortic aneurysm and severe stenosis of aortic arc.

    PubMed

    Ren, Shiyan; Sun, Guang; Yang, Yuguang; Liu, Peng

    2014-01-01

    Primary large saccular aortic aneurysm with high grade stenosis of aortic arc is rare, and no standard therapy is available. We have encountered one case and successfully treated using a hybrid interventional approach. A 59-year-old woman with a 7-day history of headache, dizziness and chest pain, and a 5-year history of hypertension admitted and was diagnosed with transverse aortic aneurysm with sever aortic stenosis, the huge saccular aneurysm was located behind the transverse aortic arc. During surgery, a bypass with graft from ascending aorta to left external iliac artery was made initially in order to ensure the blood supply to the left leg, afterward, a 40 mm × 160 mm covered stent was implanted to cover the orifice of aneurysm and was used as a supporting anchorage in the descending aorta, a second covered stent (20 mm × 100 mm) was implanted to expand the stenosis of aortic arc. Follow-up at 1.5-year after surgery, the patient has been doing well without any surgical complication. A collateral pathway between internal mammary artery and inferior epigastric artery via the superior epigastric artery was found on3-dimensional reconstruction before surgery. Interruption of the compensatory arterial collateral pathway in the patient with severe stenosis of aortic arc should be prevented if possible in order to ensure the satisfactory perfusion of the lower limbs of the body.In conclusion, a patient with transverse aortic aneurysm accompanied with severe aortic stenosis can be treated by hybrid surgery.

  17. [Surgery of aortic coarctation with aneurysm of the ascending aorta and aortic coronary fistula].

    PubMed

    Ben Jmaà, H; Abdennadher, M; Hadj Kacem, A; Masmoudi, S; Kammoun, S; Karoui, A; Frikha, I

    2009-11-01

    Aortic coarctation is rarely associated with an aneurysm of the ascending aorta and an aortic coronary fistula. In this study, we report the case of a 52-year-old man undergoing surgery for an isthmic coarctation who also had an aneurysm of the initial portion of the aorta and an aortic coronary fistula. The diagnosis was clinically suspected and confirmed by vascular catheterism. The first operative stage consisted of treating the coarctation. The second stage was performed two months later to remove the aneurysm and replace the ascending aorta and the aortic valve with a prosthesis. The coronary arteries were then reimplanted. The postoperative results were quite favourable.

  18. 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.

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

    PubMed

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

    2014-06-01

    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.

  20. The significance of aortic valve calcification in patients with bicuspid aortic valve disease.

    PubMed

    Ren, Xinshuang; Zhang, Minghui; Liu, Kun; Hou, Zhihui; Gao, Yang; Yin, Weihua; Wang, Zhiqiang; Li, Zhennan; Lu, Bin

    2016-03-01

    Bicuspid aortic valve (BAV) is a common congenital heart disease. Our study was to analyze clinical features of BAV and evaluate whether aortic valve calcium score (AVCS) was a reliable marker for aortic stenosis (AS) in patients with BAV. 101 patients with BAV who both underwent echocardiology and cardiac computed tomography (CT) scan in our institution were included. Basic clinical data, haemodynamic feature, aortic valve and coronary calcium score were collected and compared among patients with different valve function and different degree of AS. Risk factors related to severe AS were evaluated by logistic regression, and a receiver operative characteristic curve was used to determine the cutoff calcium score greater than which the diagnosis of severe AS was optimized. Patients with aortic regurgitation (AR) were younger and demonstrated larger aortic annulus and sinus compared with patients with other valve dysfunction. Aortic valve calcium score was higher in patients with AS than with AR. For patients with different degree of AS, there were statistical significances in the value of age, aortic valve calcium score and coronary calcium score. AVCS was positively related to severe AS with an odd ratio of 1.286 (95% CI 1.099-1.504) by every 300 points increase. AVCS was also a strong predictor for severe AS with area under the curve 0.855 with a cutoff value of 897 (sensitivity 86.7%, specificity 72.2%). Conclusively, aortic calcium score calculated by quantitative CT is a reliable marker in evaluating severity of AS.

  1. Emergency Transcatheter Aortic Valve Implantation for Acute and Early Failure of Sutureless Perceval Aortic Valve.

    PubMed

    Durand, Eric; Tron, Christophe; Eltchaninoff, Hélène

    2015-09-01

    We report the case of a 78-year-old woman admitted for cardiogenic shock related to acute and early failure (severe aortic regurgitation) of a Perceval sutureless aortic bioprosthesis (Sorin Group, Saluggia, Italy). Clinical stability was achieved using rescue transfemoral transcatheter aortic valve-in-valve implantation with an Edwards SAPIEN 3 prosthesis (Edwards Lifesciences, Irvine, CA). To our knowledge, we report herein the first case of successful valve-in-valve implantation using a SAPIEN 3 transcatheter heart valve in a sutureless bioprosthetic aortic valve with acute and early deterioration.

  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

    Kitahara, Hiroto; 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.

  4. [Invention of an air forced ventilated micro-isolation cage and rack system--environment within the cages: ventilation, air flow].

    PubMed

    Kurosawa, T; Yoshida, K; Okamoto, M; Tajima, M

    1993-10-01

    A forced air ventilation system for small laboratory animals was developed. The system consists of an air handling unit with air supply and exhaust fans, a rack, hard cage covers with a large diameter air inlet and an outlet, and shoe box cages. Air flow from the supply duct, to the exhaust duct and within the cage were observed. Variations in air flow among cages was minimal. The optimal air exchange rate of the cages in this system was determined to be 60 times per hour based on the results obtained in the present study. At this air exchange rate, air flow at the base of the cages had a velocity of less than 0.09m/sec, which was within the range of recommended values for humans. The observed results show that the system developed is capable of sustaining a laboratory animal microenvironment well in terms of air flow, without too much energy cost.

  5. Management of Abdominal Aortic Aneurysms.

    PubMed

    Dehlin, Jennifer M; Upchurch, Gilbert R

    2005-06-01

    Abdominal aortic aneurysms (AAAs) are a lethal disease. Ultrasound is the modality of choice for screening patients for AAAs. It is reasonable to screen patients over age 60, particularly men, women with cardiovascular risk factors, smokers, and patients with a family history of AAAs. Patients with small (< 5.5 cm) AAAs should be followed with serial ultrasound. Medical management should focus on treating comorbidities, particularly those that put patients at risk for other cardiovascular diseases. Smoking cessation is mandatory in these patients. Patients with large or symptomatic AAAs should be evaluated for surgery; this includes careful imaging of the abdomen, aggressive treatment of comorbidities, and perioperative beta blockade. Endovascular repair has lower short-term morbidity compared with conventional open repair. Trials assessing long-term results are in progress. Basic science and translational research focusing on the underlying pathogenesis of AAAs will likely pave the way for medical therapies in the future.

  6. Abdominal aortic aneurysms in women

    PubMed Central

    Lo, Ruby C.; Schermerhorn, Marc L.

    2015-01-01

    Abdominal aortic aneurysm (AAA) has long been recognized as a condition predominantly afflicting males, with sex-associated differences described for almost every aspect of the disease from pathophysiology and epidemiology to morbidity and mortality. Women are generally spared from AAA formation by the immunomodulating effects of estrogen but once they develop, the natural history of AAAs in women appears to be more aggressive, with more rapid expansion, a higher tendency to rupture at smaller diameters, and higher mortality following rupture. However, simply repairing AAA at smaller diameters in women is a debatable solution, as even elective endovascular AAA repair (EVAR) is fraught with higher morbidity and mortality in women compared to men. The goal of this review is to summarize what is currently known about the effect of gender on AAA presentation, treatment, and outcomes. Additionally, we aim to review current controversies over screening recommendations and threshold for repair in women. PMID:26747679

  7. Effects of wind speed on aerosol spray penetration in adult mosquito bioassay cages.

    PubMed

    Hoffmann, W Clint; Fritz, Bradley K; Farooq, Muhammad; Cooperband, Miriam F

    2008-09-01

    Bioassay cages are commonly used to assess efficacy of insecticides against adult mosquitoes in the field. To correlate adult mortality readings to insecticidal efficacy and/or spray application parameters properly, it is important to know how the cage used in the bioassay interacts with the spray cloud containing the applied insecticide. This study compared the size of droplets, wind speed, and amount of spray material penetrating cages and outside of cages in a wind tunnel at different wind speeds. Two bioassay cages, Center for Medical, Agricultural and Veterinary Entomology (CMAVE) and Circle, were evaluated. The screen materials used on these cages reduced the size of droplets, wind speed, and amount of spray material inside the cages as compared to the spray cloud and wind velocity outside of the cages. When the wind speed in the dispersion tunnel was set at 0.6 m/sec (1.3 mph), the mean wind speed inside of the CMAVE Bioassay Cage and Circle Cage was 0.045 m/sec (0.10 mph) and 0.075 m/sec (0.17 mph), respectively. At air velocities of 2.2 m/sec (4.9 mph) in the dispersion tunnel, the mean wind speed inside of the CMAVE Bioassay Cage and Circle Cage was 0.83 m/sec (1.86 mph) and 0.71 m/sec (1.59 mph), respectively. Consequently, there was a consistent 50-70% reduction of spray material penetrating the cages compared to the spray cloud that approached the cages. These results provide a better understanding of the impact of wind speed, cage design, and construction on ultra-low-volume spray droplets.

  8. Surveillance after endovascular aortic repair.

    PubMed

    Zaiem, Feras; Almasri, Jehad; Tello, Mouaffaa; Prokop, Larry J; Chaikof, Elliot L; Murad, Mohammad Hassan

    2017-06-26

    The objective of this systematic review and meta-analysis was to evaluate the optimal modality and frequency of surveillance after endovascular aortic repair (EVAR) in adult patients with abdominal aortic aneurysms. We searched for studies of post-EVAR surveillance in MEDLINE In-Process & Other Non-Indexed Citations, MEDLINE, Embase, Cochrane Database of Systematic Reviews, and Scopus through May 10, 2016. The outcomes of interest were endoleaks, mortality, limb ischemia, renal complications, late rupture, and aneurysm-related mortality. Outcomes were pooled using a random-effects model and were reported as incidence rate and 95% confidence interval. Of 1099 candidate references, we included 6 meta-analyses and 52 observational studies. Complication rates were common after EVAR, particularly in the first year. Magnetic resonance imaging had a higher detection rate of endoleaks than computed tomography angiography. Doppler ultrasound had lower diagnostic accuracy, whereas contrast-enhanced ultrasound was likely to be as sensitive as computed tomography angiography. The highest endoleak detection rates were in surveillance approaches that used combined tests. There were no studies that compared different surveillance intervals to determine optimal intervals; however, most studies reported detection rates of patient-important outcomes at 1, 6, 12, 24, 36, 48, and 60 months. Data were insufficient to provide comparative inferences about the best strategy to reduce the risk of patient-important outcomes, such as mortality, limb ischemia, rupture, and renal complications. Several tests with reasonable diagnostic accuracy are available for surveillance after EVAR. The available evidence suggests a high complication rate, particularly in the first year, and provides a rationale for surveillance. Published by Elsevier Inc.

  9. Computational analysis of an aortic valve jet

    NASA Astrophysics Data System (ADS)

    Shadden, Shawn C.; Astorino, Matteo; Gerbeau, Jean-Frédéric

    2009-11-01

    In this work we employ a coupled FSI scheme using an immersed boundary method to simulate flow through a realistic deformable, 3D aortic valve model. This data was used to compute Lagrangian coherent structures, which revealed flow separation from the valve leaflets during systole, and correspondingly, the boundary between the jet of ejected fluid and the regions of separated, recirculating flow. Advantages of computing LCS in multi-dimensional FSI models of the aortic valve are twofold. For one, the quality and effectiveness of existing clinical indices used to measure aortic jet size can be tested by taking advantage of the accurate measure of the jet area derived from LCS. Secondly, as an ultimate goal, a reliable computational framework for the assessment of the aortic valve stenosis could be developed.

  10. Gallium localization in dissecting aortic aneurysm

    SciTech Connect

    Haden, H.T.; Lippman, H.R.

    1988-08-01

    Gallium concentration was demonstrated in a dissecting aneurysm of the aortic arch, imaged approximately 2 weeks after dissection. Concentration of gallium was apparently due to the inflammatory reaction associated with the organizing intramural hematoma.

  11. Aortic Dissection and Rupture in a Child

    PubMed Central

    Jo, Yun Ju; Lee, Eun Jeong; Oh, Jin Won; Moon, Chang Min; Cho, Deok Kyu; Cho, Yun Hyeong; Byun, Ki Hyun

    2011-01-01

    After developing sudden severe chest pain, an 11-year-old boy presented to the emergency room with chest pain and palpitations and was unable to stand up. The sudden onset of chest pain was first reported while swimming at school about 30 minutes prior to presentation. Arterial blood pressure (BP) was 150/90 mmHg, heart rate was 120/minute, and the chest pain was combined with shortness of breath and diaphoresis. During the evaluation in the emergency room, the chest pain worsened and abdominal pain developed. An aortic dissection was suspected and a chest and abdomen CT was obtained. The diagnosis of aortic dissection type B was established by CT imaging. The patient went to surgery immediately with BP control. He died prior to surgery due to aortic rupture. Here we present this rare case of aortic dissection type B with rupture, reported in an 11-year-old Korean child. PMID:21519516

  12. 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

  13. 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 © 2017 BroadcastMed, Inc. ...

  14. Treating calcific aortic stenosis: an evolving science.

    PubMed

    Hull, Christine L

    2012-01-01

    Calcific aortic stenosis is a common valvular disease, but its pathophysiology remains undetermined and important considerations exist for treatment. Pathophysiology, treatment by the advanced practice nurse, and literature review are discussed in the context of a case study.

  15. Valve selection in aortic valve endocarditis

    PubMed Central

    Zubrytska, Yana

    2016-01-01

    Aortic prosthetic valve endocarditis (PVE) is a potentially life-threatening disease. Mortality and incidence of infective endocarditis have been reduced in the past 30 years. Medical treatment of aortic PVE may be successful in patients who have a prompt response after antibiotic treatment and who do not have prosthetic dysfunction. In advanced stages, antibiotic therapy alone is insufficient to control the disease, and surgical intervention is necessary. Surgical treatment may be lifesaving, but it is still associated with considerable morbidity and mortality. The aim of surgery is to perform a radical excision of all infected and necrotic tissue, reconstruction of the left ventricle outflow tract, and replacement of the aortic valve. There is no unanimous consensus on which is the optimal prosthesis to implant in this context, and several surgical techniques have been suggested. We aim to analyze the efficacy of the surgical treatment and discuss the issue of valve selection in patients with aortic valve endocarditis. PMID:27785132

  16. Aortic intramural hematoma: an unpredictable evolution.

    PubMed

    Ponte, Marta; Dias Ferreira, Nuno; Bettencourt, Nuno; Caeiro, Daniel; Fonseca, Marlene; Albuquerque, Aníbal; Vouga, Luís; Gama, Vasco

    2014-01-01

    Aortic intramural hematoma (IMH) is an acute aortic syndrome characterized by bleeding into the media of the aortic wall without intimal disruption or the classic flap formation. Its natural history is variable and still poorly understood, so strategies for therapeutic management are not fully established. In some cases there is partial or complete regression of the hematoma under medical treatment, but most progress to dissection, aneurysmal dilatation or aortic rupture. The authors present the case of a 44-year-old hypertensive male patient admitted with a diagnosis of IMH of the descending aorta. Despite initial symptom resolution and optimal medical therapy, the IMH evolved to a pseudoaneurysm, which was successfully treated by an endovascular approach. Copyright © 2013 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

  17. 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. © 2012 The Authors. Animal Science Journal © 2012 Japanese Society of Animal Science.

  18. Effects of separation of resources on behaviour, physical condition and production of laying hens in furnished cages.

    PubMed

    Shimmura, T; Azuma, T; Eguchi, Y; Uetake, K; Tanaka, T

    2009-01-01

    1. Based on our previous studies, we designed a medium-sized furnished cage with a dust bath and nest box on both sides of the cage (MFS) and evaluated its usefulness. 2. We used 180 White Leghorn layers. At the age of 17 weeks, the birds were distributed at random into one of the 4 cage designs: conventional cages (CC; 6 cages and 5 hens per cage), small (SF; 6 cages and 5 hens per cage) and medium furnished cages (MFL; 6 cages and 10 hens per cage) with a 'localised' dust bath and nest box on one side of the cage, and MFS (6 cages and 10 hens per cage). The total allocation of resources per bird was similar for all furnished cage designs. Behaviour, physical condition and production were measured in each cage. 3. Moving was more frequent in MFS and MFL than in CC and SF. The proportion of hens performing aggressive pecking and severe feather pecking was higher in MFL than CC and SF. These aggressive interactions occurred frequently in the dust bath area in MFL; however, these tendencies were not found in MFS. Egg production and egg mass were lower in MFL than in SF, while the production in MFS was similar to those in CC and SF. MFS hens laid eggs on the cage floor more often than in MFL. 4. In conclusion, these results demonstrate the possible usefulness of MFS. However, some inconsistent results and ways of improving MFS design were also identified.

  19. Anterior longitudinal aortotomy in aortic valve replacement.

    PubMed

    Matsuzaki, Kanji; Kudo, Yohei; Ikeda, Akihiko; Konishi, Taisuke; Jikuya, Tomoaki

    2016-02-01

    We adopted an anterior longitudinal aortotomy in some cases of aortic valve replacement (AVR), and report them here. The potential of this method is also discussed. We analyzed the data on 24 patients (75.5 ± 7.8 years of age) who had undergone AVR through anterior longitudinal aortotomy. The indications for surgery were prosthetic valve complication in 5 patients, aortic stenosis (AS) with left ventricular outflow tract stenosis (LVOTS) in 16 patients, and aortic regurgitation with moderately dilated ascending aorta in 3 patients. The Konno procedure was performed in 6 cases with small aortic annuli. A longitudinal aortotomy was made at the aortic root along the left side of the right coronary ostium, and extended beyond the right coronary annulus to the interventricular septum as needed. Bioprostheses (21.1 ± 1.7 mm) were used in 23 patients and a 21-mm mechanical valve for one (a 59-year-old man). One high-risk patient died of low output syndrome, leading to a mortality rate of 4.2 %. All other patients recovered well, though atrioventricular block occurred in 2 cases. Anterior longitudinal aortotomy provides a good field of vision at the aortic annulus and the flexibility to develop into anterior annular enlargement. Major indications for this approach are small sino-tubular junction and very small aortic annulus. This approach could be an attractive option in AVR for cases of AS with small aortic annuli and LVOTS. It could also be useful for AVR cases with moderately dilated ascending aorta requiring aortoplasty.

  20. Aortic coarctation repair in the adult.

    PubMed

    Cardoso, Goncalo; Abecasis, Miguel; Anjos, Rui; Marques, Marta; Koukoulis, Giovanna; Aguiar, Carlos; Neves, José Pedro

    2014-07-01

    Aortic coarctation can be repaired surgically or percutaneously. The decision should be made according to the anatomy and location of the coarctation, age of the patient, presence of other cardiac lesions, and other anatomic determinants (extensive collaterals or aortic calcification). This article reviews the different therapeutic options available, explaining the differences between children and adults, describing different approaches to the same disease, exemplified by three cases of nonclassic surgical approach and one percutaneous treatment.

  1. Complete cage migration/subsidence into the adjacent vertebral body after posterior lumbar interbody fusion.

    PubMed

    Corniola, Marco V; Jägersberg, Max; Stienen, Martin N; Gautschi, Oliver P

    2015-03-01

    A variety of implant-related short and long-term complications after lumbar fusion surgery are recognized. Mid to long-term complications due to cage migration and/or cage subsidence are less frequently reported. Here, we report a patient with a complete cage migration into the superior adjacent vertebral body almost 20 years after the initial posterior lumbar interbody fusion procedure. In this patient, the cage migration/subsidence was clinically silent, but a selective decompression for adjacent segment degenerative lumbar spinal stenosis was performed. We discuss the risk factors for cage migration/subsidence in view of the current literature.

  2. 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.

  3. Long-term durability of preserved aortic root after repair of acute type A aortic dissection.

    PubMed

    Kamohara, Keiji; Koga, Shugo; Takaki, Jun; Yoshida, Nozomi; Furukawa, Kojiro; Morita, Shigeki

    2017-08-01

    Optimal management of aortic root in type A aortic dissection (AAD) is controversial. To determine the most appropriate strategy, we studied the late outcomes after conservative repair of aortic root. 234 AAD patients (mean age 68 ± 12 years) underwent surgical repair using supracommissural replacement (SCR) for aortic root reconstruction from 1989 to 2014. Ascending aortic replacement or hemi-arch replacement was performed in 180 patients (non-arch group), whereas total arch replacement (TAR) was performed in 54 patients. In both groups, proper and firm reapproximation of proximal edge was performed exactly at the sinotubular junction (STJ). The long-term durability of preserved aortic root (mean follow-up 89 months) was evaluated. Hospital mortality occurred in 25 of 234 patients (10.6%). Aorta-related deaths occurred in five patients (four in non-arch; one in TAR), with over 90% 10-year actuarial survival rate in each group. Among 19 aorta-related events, there were only four proximal events (three in non-arch; one in TAR). The 10-year freedom rate from proximal aorta-related events exceeded 90%, with no significant difference in both groups. Freedom rate from moderate aortic regurgitation at 10 years was statistically similar between non-arch (86.3%) and TAR (85.7%) groups. The long-term durability of SCR with proximal aortic reapproximation exactly at the STJ was acceptable with low rates of proximal aortic events. This technique can be the standard technique for aortic root reconstruction in AAD patients, except those with aortic root pathology.

  4. Semi-automatic aortic aneurysm analysis

    NASA Astrophysics Data System (ADS)

    Bodur, Osman; Grady, Leo; Stillman, Arthur; Setser, Randolph; Funka-Lea, Gareth; O'Donnell, Thomas

    2007-03-01

    Aortic aneurysms are the 13 th leading cause of death in the United States. In standard clinical practice, assessing the progression of disease in the aorta, as well as the risk of aneurysm rupture, is based on measurements of aortic diameter. We propose a method for automatically segmenting the aortic vessel border allowing the calculation of aortic diameters on CTA acquisitions which is accurate and fast, allowing clinicians more time for their evaluations. While segmentation of aortic lumen is straightforward in CTA, segmentation of the outer vessel wall (epithelial layer) in a diseased aorta is difficult; furthermore, no clinical tool currently exists to perform this task. The difficulties are due to the similarities in intensity of surrounding tissue (and thrombus due to lack of contrast agent uptake), as well as the complications from bright calcium deposits. Our overall method makes use of a centerline for the purpose of resampling the image volume into slices orthogonal to the vessel path. This centerline is computed semi-automatically via a distance transform. The difficult task of automatically segmenting the aortic border on the orthogonal slices is performed via a novel variation of the isoperimetric algorithm which incorporates circular constraints (priors). Our method is embodied in a prototype which allows the loading and registration of two datasets simultaneously, facilitating longitudinal comparisons. Both the centerline and border segmentation algorithms were evaluated on four patients, each with two volumes acquired 6 months to 1.5 years apart, for a total of eight datasets. Results showed good agreement with clinicians' findings.

  5. Minimally invasive "pocket incision" aortic valve surgery.

    PubMed

    Yakub, M A; Pau, K K; Awang, Y

    1999-02-01

    A minimally invasive approach to aortic valve surgery through a transverse incision ("pocket incision") at the right second intercostal space was examined. Sixteen patients with a mean age of 30 years underwent this approach. The third costal cartilage was either excised (n = 5) or dislocated (n = 11). The right internal mammary artery was preserved. Cardiopulmonary bypass (CPB) was established with aortic-right atrial cannulation in all except the first case. Aortic valve replacements (AVR) were performed in 15 patients and one had aortic valve repair with concomitant ventricular septal defect closure. There was no mortality and no major complications. The aortic cross-clamp, CPB and operative times were 72 +/- 19 mins, 105 +/- 26 mins and 3 hrs 00 min +/- 29 mins respectively. The mean time to extubation was 5.7 +/- 4.0 hrs, ICU stay of 27 +/- 9 hrs and postoperative hospital stay of 5.1 +/- 1.2 days. Minimally invasive "pocket incision" aortic valve surgery is technically feasible and safe. It has the advantages of central cannulation for CPB, preservation of the internal mammary artery and avoiding sternotomy. This approach is cosmetically acceptable and allows rapid patient recovery.

  6. Quantification of abdominal aortic deformation after EVAR

    NASA Astrophysics Data System (ADS)

    Demirci, Stefanie; Manstad-Hulaas, Frode; Navab, Nassir

    2009-02-01

    Quantification of abdominal aortic deformation is an important requirement for the evaluation of endovascular stenting procedures and the further refinement of stent graft design. During endovascular aortic repair (EVAR) treatment, the aortic shape is subject to severe deformation that is imposed by medical instruments such as guide wires, catheters, and, the stent graft. This deformation can affect the flow characteristics and morphology of the aorta which have been shown to be elicitors for stent graft failures and be reason for reappearance of aneurysms. We present a method for quantifying the deformation of an aneurysmatic aorta imposed by an inserted stent graft device. The outline of the procedure includes initial rigid alignment of the two abdominal scans, segmentation of abdominal vessel trees, and automatic reduction of their centerline structures to one specified region of interest around the aorta. This is accomplished by preprocessing and remodeling of the pre- and postoperative aortic shapes before performing a non-rigid registration. We further narrow the resulting displacement fields to only include local non-rigid deformation and therefore, eliminate all remaining global rigid transformations. Finally, deformations for specified locations can be calculated from the resulting displacement fields. In order to evaluate our method, experiments for the extraction of aortic deformation fields are conducted on 15 patient datasets from endovascular aortic repair (EVAR) treatment. A visual assessment of the registration results and evaluation of the usage of deformation quantification were performed by two vascular surgeons and one interventional radiologist who are all experts in EVAR procedures.

  7. Gender Differences in Abdominal Aortic Aneurysms

    PubMed Central

    Hannawa, Kevin K.; Eliason, Jonathan L.; Upchurch, Gilbert R.

    2010-01-01

    Abdominal aortic aneurysms (AAAs) comprise the 10th leading cause of death in Caucasian males 65–74 years of age, and accounted for nearly 16,000 deaths overall in the year 2000. Therefore, understanding the pathophysiology of AAAs is an important undertaking. Clinically, multiple risk factors are associated with the development of AAAs, including increasing age, positive smoking history, and hypertension. Male gender is also a well-established risk factor for the development of an AAA with a 4:1 male to female ratio. The reason for this gender disparity is unknown. The pathogenesis of AAAs formation is complex and multifactorial. Histologically, AAAs are characterized by early chemokine driven leukocyte infiltration into the aortic wall. Subsequent destruction of elastin and collagen in the media and adventitia ensues due to excessive local production of matrix degrading enzymes, and is accompanied by smooth muscle cell loss and thinning of the aortic wall. At present, there are no medical therapies available to treat patients with aortic aneurysms, using only the crude measurement of aortic diameter as a threshold for which patients must undergo life-threatening and costly surgery. Defining the early mechanisms underlying gender-related differences in AAA formation are critical, as understanding differences in disease patterns based on gender may allow us to develop new translational approaches to the prevention and treatment of patients with aortic aneurysms. PMID:19426607

  8. Gender differences in abdominal aortic aneurysms.

    PubMed

    Hannawa, Kevin K; Eliason, Jonathan L; Upchurch, Gilbert R

    2009-01-01

    Abdominal aortic aneurysms (AAAs) comprise the tenth leading cause of death in Caucasian males 65 to 74 years of age and accounted for nearly 16,000 deaths overall in 2000. Therefore, understanding the pathophysiology of AAAs is an important undertaking. Clinically, multiple risk factors are associated with the development of AAAs, including increasing age, positive smoking history, and hypertension. Male gender is also a well-established risk factor for the development of an AAA, with a 4:1 male to female ratio. The reason for this gender disparity is unknown. The pathogenesis of AAAs formation is complex and multifactorial. Histologically, AAAs are characterized by early chemokine-driven leukocyte infiltration into the aortic wall. Subsequent destruction of elastin and collagen in the media and adventitia ensues owing to excessive local production of matrix-degrading enzymes and is accompanied by smooth muscle cell loss and thinning of the aortic wall. At present, no medical therapies are available to treat patients with aortic aneurysms, using only the crude measurement of aortic diameter as a threshold for which patients must undergo life-threatening and costly surgery. Defining the early mechanisms underlying gender-related differences in AAA formation is critical as understanding differences in disease patterns based on gender may allow us to develop new translational approaches to the prevention and treatment of patients with aortic aneurysms.

  9. Fetal sonographic diagnosis of aortic arch anomalies.

    PubMed

    Yoo, S-J; Min, J-Y; Lee, Y-H; Roman, K; Jaeggi, E; Smallhorn, J

    2003-11-01

    Aortic arch anomalies refer to congenital abnormalities of the position or branching pattern, or both of the aortic arch. Although aortic arch anomalies are not uncommon, reports on their prenatal diagnosis are scarce. Insight into the hypothetical arch model is crucial to understanding anomalies of the aortic arch in the fetus. Recognition of the trachea, three major vessels, ductus arteriosus and descending aorta in the axial views of the upper mediastinum is necessary for a complete fetal cardiac assessment. Clues to aortic arch anomalies include abnormal position of the descending aorta, absence of the normal 'V'-shaped confluence of the ductal and aortic arches, a gap between the ascending aorta and main pulmonary artery in the three-vessel view, and an abnormal vessel behind the trachea with or without a vascular loop or ring around the trachea. Meticulous attention to anatomic landmarks will lead to successful prenatal diagnosis of important vascular rings making early postnatal management possible. Copyright 2003 ISUOG. Published by John Wiley & Sons, Ltd.

  10. Measurement of aortic regurgitation by Doppler echocardiography.

    PubMed Central

    Zhang, Y; Nitter-Hauge, S; Ihlen, H; Rootwelt, K; Myhre, E

    1986-01-01

    In an attempt to develop a new approach to the non-invasive measurement of aortic regurgitation, transmitral volumetric flow (MF) and left ventricular total stroke volume (SV) were measured by Doppler and cross sectional echocardiography in 23 patients without aortic valve disease (group A) and in 26 patients with aortic regurgitation (group B). The transmitral volumetric flow was obtained by multiplying the corrected mitral orifice area by the diastolic velocity integral, and the left ventricular total stroke volume was derived by subtracting the left ventricular end systolic volume from the end diastolic volume. The aortic regurgitant fraction (RF) was calculated as: RF = 1 - MF/SV. In group A there was a close agreement between the transmitral volumetric flow and the left ventricular total stroke volume, and the difference between the two measurements did not differ significantly from zero. In group B the left ventricular total stroke volume was significantly larger than the transmitral volumetric flow, and there was good agreement between the regurgitant fractions determined by Doppler echocardiography and radionuclide ventriculography. Discrepancies between the two techniques were found in patients with combined aortic and mitral regurgitation or a low angiographic left ventricular ejection fraction (less than 35%). The effective cardiac output measured by Doppler echocardiography accorded well with that measured by the Fick method. Doppler echocardiography provides a new and promising approach to the non-invasive measurement of aortic regurgitation. PMID:3947478

  11. Cellular Mechanisms of Aortic Valve Calcification

    PubMed Central

    Leopold, Jane A.

    2012-01-01

    Acquired aortic valve disease and valvular calcification is highly prevalent in adult populations worldwide and is associated with significant cardiovascular morbidity and mortality. At present, there are no medical therapies that will prevent or regress aortic valve calcification or stenosis and surgical or transcatheter aortic valve replacement remain the only effective therapies for treating this disease. In the setting of valve injury as a result of exposure to biochemical mediators or hemodynamic forces, normal homeostatic processes are disrupted resulting in extracellular matrix degradation, aberrant matrix deposition and fibrosis, inflammatory cell infiltration, lipid accumulation, and neoangiogenesis of the valve tissue and, ultimately, calcification of the valve. Calcification of the aortic valve is now understood to be an active process that involves the coordinated actions of resident valve endothelial and interstitial cells, circulating inflammatory and immune cells, and bone marrow-derived cells. These cells may undergo a phenotype transition to become osteoblast-like cells and elaborate bone matrix, endothelial-to-mesenchymal transition, and form matrix vesicles that serve as a nidus for microcalcifications. Each of these mechanisms has been shown to contribute to aortic valve calcification suggesting that strategies that target these cellular events may lead to novel therapeutic interventions to halt the progression or reverse aortic valve calcification. PMID:22896576

  12. 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

  13. Transient hypertension and sustained tachycardia in mice housed individually in metabolism cages.

    PubMed

    Hoppe, C C; Moritz, K M; Fitzgerald, S M; Bertram, J F; Evans, R G

    2009-01-01

    The novel environment of a metabolic cage can be stressful for rodents, but few studies have attempted to quantify this stress-response. Therefore, we determined the effects on mean arterial pressure (MAP) and heart rate (HR), of placing mice of both sexes in metabolism cages for 2 days. After surgical implantation of a carotid artery catheter mice recovered individually in standard cages for 5 days. Mice then spent 2 days in metabolism cages. MAP and HR were monitored in the standard cage on Day 5 and in metabolism cages on Days 6-7. MAP increased by 18+/-3 and 22+/-4 %, while HR increased by 27+/-4 and 27+/-6 %, in males and females, respectively, during the first hours after cage switch. MAP decreased to baseline in the fourth and eighth h following metabolism cage switch in males and females, respectively. However, HR remained significantly elevated in both sexes during the entire two-day period in metabolism cages. Females had lower MAP than males both pre- and post-metabolism cage switch, but there were no sex differences in HR. These results demonstrate sustained changes in cardiovascular function when mice are housed in metabolism cages, which could potentially affect renal function.

  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.

  15. Robot assisted Aortic and Non-aortic Vascular Operations.

    PubMed

    Štádler, P; Dvořáček, L; Vitásek, P; Matouš, P

    2016-07-01

    The aim of this study was to evaluate the clinical experience with 310 robot assisted vascular procedures. The da Vinci system has been used by a variety of disciplines for laparoscopic procedures but the use of robots in vascular surgery is still relatively uncommon. From November 2005 to May 2014, 310 robot assisted vascular operations were performed. Two hundred and twenty four patients were prospectively evaluated for occlusive disease, 61 patients for abdominal aortic aneurysm, four for a common iliac artery aneurysm, four for a splenic artery aneurysm, one for a internal mammary artery aneurysm, and after the unsuccessful endovascular treatment five for hybrid procedures, two patients for median arcuate ligament release and nine for endoleak II treatment post EVAR. Among these patients, 224 underwent robotic occlusive disease treatment (Group I), 65 robotic aorto-iliac aneurysm surgery (Group II) and 21 other robotic procedures (Group III). A total of 298 cases (96.1%) were successfully completed robotically. In 10 patients (3.2%) conversion was necessary. The 30 day mortality was 0.3%, and two (0.6%) late prosthetic infections were seen. Targeted Group I and Group II patients were compared. Robotic ilio-femoral bypass, aorto-femoral bypass, or aorto-iliac thrombo-endarterectomy with prosthetic patch (Group I) required an operative time of 194 (range, 127-315) minutes and robotic aorto-iliac aneurysm surgery (Group II), 253 (range, 185-360) minutes. The mean aortic cross clamping time was 37 minutes in Group I and 93 minutes in Group II. The mean blood loss was more significant in Group II (1,210 mL) than in Group I (320 mL). From a practical point of view, the greatest advantage of the robot assisted procedure has been the speed and relative simplicity of construction of the vascular anastomosis. This experience with robot assisted laparoscopic surgery has demonstrated the feasibility of this technique in different areas of vascular surgery. Copyright

  16. Early aortic valve cusp rupture in relapsing polychondritis.

    PubMed Central

    Marshall, D A; Jackson, R; Rae, A P; Capell, H A

    1992-01-01

    Aortic regurgitation associated with relapsing polychondritis usually occurs late in the disease as a result of aortic root dilatation. A case where aortic regurgitation occurred early and was due to cusp rupture with a normal aortic root is reported. The patient required urgent aortic valve replacement within six weeks of developing a murmur despite apparent control of inflammation with immunosuppressive treatment. The possibility of cusp rupture with sudden haemodynamic deterioration should be considered in patients with relapsing polychondritis who develop aortic regurgitation. Images PMID:1575597

  17. Valve sparing: aortic root replacement with the reimplantation technique.

    PubMed

    Mastrobuoni, Stefano; Tamer, Sadallah; de Kerchove, Laurent; El Khoury, Gebrine

    2015-01-01

    Aortic valve-sparing procedures are alternative options to aortic valve replacement in patients with aortic root aneurysm and/or severe aortic regurgitation reducing the risk of prosthesis-related complications, such as thromboembolism, and have no need for long-term oral anticoagulation. However, these techniques are technically demanding and long-term results are highly dependent on perfect intraoperative restoration of valve function. We describe a systematic approach to aortic valve-sparing aortic root replacement with the reimplantation technique the way it is currently performed in our institution.

  18. 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.

  19. 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.

  20. 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.

  1. Extreme ultraviolet patterning of tin-oxo cages

    NASA Astrophysics Data System (ADS)

    Haitjema, Jarich; Zhang, Yu; Vockenhuber, Michaela; Kazazis, Dimitrios; Ekinci, Yasin; Brouwer, Albert M.

    2017-03-01

    We report on the extreme ultraviolet (EUV) patterning performance of tin-oxo cages: molecular building blocks that are known to turn insoluble upon EUV exposure, thus having the properties of a negative tone photoresist. In this work, we focus on contrast curves of the materials using open-frame EUV exposures and their patterning capabilities using EUV interference lithography. It is shown that baking steps, such as post-exposure baking (PEB) can significantly affect both the sensitivity and contrast in the open-frame experiments as well as the patterning experiments. In addition, we show that the exchange of the anions of the cage can make a difference in terms of their physical properties. Our results demonstrate the significance of process optimization while evaluating the resist performance of novel molecular materials.

  2. Supramolecular Archimedean cages assembled with 72 hydrogen bonds.

    PubMed

    Liu, Yuzhou; Hu, Chunhua; Comotti, Angiolina; Ward, Michael D

    2011-07-22

    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···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.

  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. 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

  5. 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.

  6. Oriented Two-Dimensional Porous Organic Cage Crystals.

    PubMed

    Jiang, Shan; Song, Qilei; Massey, Alan; Chong, Samantha Y; Chen, Linjiang; Sun, Shijing; Hasell, Tom; Raval, Rasmita; Sivaniah, Easan; Cheetham, Anthony K; Cooper, Andrew I

    2017-08-01

    The formation of two-dimensional (2D) oriented porous organic cage crystals (consisting of imine-based tetrahedral molecules) on various substrates (such as silicon wafers and glass) by solution-processing is reported. Insight into the crystallinity, preferred orientation, and cage crystal growth was obtained by experimental and computational techniques. For the first time, structural defects in porous molecular materials were observed directly and the defect concentration could be correlated with crystal growth rate. These oriented crystals suggest potential for future applications, such as solution-processable molecular crystalline 2D membranes for molecular separations. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  7. Spatiotemporal Control of Embryonic Gene Expression Using Caged Morpholinos

    PubMed Central

    Shestopalov, Ilya A.; Chen, James K.

    2015-01-01

    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

  8. Rotational Brownian dynamics simulations of clathrin cage formation.

    PubMed

    Ilie, Ioana M; den Otter, Wouter K; Briels, Wim J

    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.

  9. Macromolecularly "Caged" Carbon Nanoparticles for Intracellular Trafficking via Switchable Photoluminescence.

    PubMed

    Misra, Santosh K; Srivastava, Indrajit; Tripathi, Indu; Daza, Enrique; Ostadhossein, Fatemeh; Pan, Dipanjan

    2017-02-08

    Reversible switching of photoluminescence (PL) of carbon nanoparticles (CNP) can be achieved with counterionic macromolecular caging and decaging at the nanoscale. A negatively charged uncoated, "bare" CNP with high luminescence loses its PL when positively charged macromolecules are wrapped around its surface. Prepared caged carbons could regain their emission only through interaction with anionic surfactant molecules, representing anionic amphiphiles of endocytic membranes. This process could be verified by gel electrophoresis, spectroscopically and in vitro confocal imaging studies. Results indicated for the first time that luminescence switchable CNPs can be synthesized for efficient intracellular tracking. This study further supports the origin of photoluminescence in CNP as a surface phenomenon correlated a function of characteristic charged macromolecules.

  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. Segmental kyphosis after cervical interbody fusion with stand-alone polyetheretherketone (PEEK) cages: a comparative study on 2 different PEEK cages.

    PubMed

    Kim, Chi Heon; Chung, Chun Kee; Jahng, Tae-Ahn; Park, Sung Bae; Sohn, Seil; Lee, Sungjoon

    2015-02-01

    Retrospective comparative study. Two polyetheretherketone (PEEK) cages of different designs were compared in terms of the postoperative segmental kyphosis after anterior cervical discectomy and fusion. Segmental kyphosis occasionally occurs after the use of a stand-alone cage for anterior cervical discectomy and fusion. Although PEEK material seems to have less risk of segmental kyphosis compared with other materials, the occurrence of segmental kyphosis for PEEK cages has been reported to be from 0% to 29%. There have been a few reports that addressed the issue of PEEK cage design. A total of 41 consecutive patients who underwent single-level anterior discectomy and fusion with a stand-alone cage were included. Either a round tube-type (Solis; 18 patients, S-group) or a trapezoidal tube-type (MC+; 23 patients, M-group) cage was used. The contact area between the cage and the vertebral body is larger in MC+ than in Solis, and anchoring pins were present in the Solis cage. The effect of the cage type on the segmental angle (SA) (lordosis vs. kyphosis) at postoperative month 24 was analyzed. Preoperatively, segmental lordosis was present in 12/18 S-group and 16/23 M-group patients (P=0.84). The SA was more lordotic than the preoperative angle in both groups just after surgery, with no difference between groups (P=0.39). At 24 months, segmental lordosis was observed in 9/18 S-group and 20/23 M-group patients (P=0.01). The patients in M-group were 7.83 times more likely than patients in S-group (P=0.04; odds ratio, 7.83; 95% confidence interval, 1.09-56.28) not to develop segmental kyphosis. The design of the PEEK cage used may influence the SA, and this association needs to be considered when using stand-alone PEEK cages.

  12. Flow Tagging Velocimetry Using Caged Dye Photo-Activated Fluorophores

    DTIC Science & Technology

    2000-01-01

    Meas. Sci. Technol. 11 (2000) 1251–1258. Printed in the UK PII: S0957-0233(00)10968-3 Flow tagging velocimetry using caged dye photo-activated...followed by laser induced electronic fluo- rescence, has been applied both to low speed turbulent air jets (Noullez et al 1997) and to supersonic flow...measurements in electrohydrodynamic flows with mean velocities of order 2–4 µm s−1. There are, however, some significant disadvantages associated with

  13. Home cage testing of delay discounting in rats.

    PubMed

    Koot, S; Adriani, W; Saso, L; van den Bos, R; Laviola, G

    2009-11-01

    Testing rodents in their home cages has become increasingly popular. Since human intervention, handling, and transport are minimized, behavior can be recorded undisturbed and continuously. Currently existing home cage systems are too complex if only relatively simple operant-learning tests are to be carried out in rats. For that purpose, a new low-cost computer-controlled operant panel was designed, which can be placed inside the home cage. A pilot study was carried out, using an intolerance-to-delay protocol, classically developed for testing behavioral impulsivity. Male adult rats were tested in their home cages, containing the operant panel provided with nose-poking holes. Nose poking in one hole resulted in the immediate delivery of one food pellet (small-soon, SS), whereas nose poking in the other hole delivered five food pellets after a delay (large-late), which was increased progressively each day (0-150 sec). The two daily sessions, spaced 8 h apart, lasted 1 h each, and the time-out after food delivery was 90 sec. A clear-cut shift toward preference for SS, which is considered a classical index of cognitive impulsivity, was shown at the longest delay. It is noteworthy that rats shifted when the delay interval was longer than the mean intertrial interval-that is, when they experienced more than one delay-equivalent odds against discounting (see Adriani & Laviola, 2006). The shortened training (2 days) and testing (5 days) phases, as allowed by prolonged and multiple daily sessions, can be advantageous in testing rodents during selected short phases of development. Current research is focusing on further validation of this and similar protocols.

  14. Alistonitrine A, a caged monoterpene indole alkaloid from Alstonia scholaris.

    PubMed

    Zhu, Guo-Yuan; Yao, Xiao-Jun; Liu, Liang; Bai, Li-Ping; Jiang, Zhi-Hong

    2014-02-21

    Alistonitrine A, a new monoterpene indole alkaloid incorporating a third nitrogen atom, was isolated from the leaves of Alstonia scholaris and found to possess an unprecedented caged skeleton with a unique 6/5/6/5/5/6 ring system. Its structure and absolute configuration were established by extensive spectroscopic analyses and electron circular dichroism calculations. A plausible biogenetic pathway has been proposed for the biosynthesis of alistonitrine A from picrinine.

  15. A calibration model for screen-caged Peltier thermocouple psychrometers

    Treesearch

    Ray W. Brown; Dale L. Bartos

    1982-01-01

    A calibration model for screen-caged Peltier thermocouple psychrometers was developed that applies to a water potential range of 0 to-80 bars, over a temperature range of 0° to 40° C, and for cooling times of 15 to 60 seconds. In addition, the model corrects for the effects of temperature gradients over zero-offsets from -60 to + 60 microvolts. Complete details of...

  16. Aortic assessment of bicuspid aortic valve patients and their first-degree relatives.

    PubMed

    Straneo, Pablo; Parma, Gabriel; Lluberas, Natalia; Marichal, Alvaro; Soca, Gerardo; Cura, Leandro; Paganini, Juan J; Brusich, Daniel; Florio, Lucia; Dayan, Victor

    2017-03-01

    Background Bicuspid aortic valve patients have an increased risk of aortic dilatation. A deficit of nitric oxide synthase has been proposed as the causative factor. No correlation between flow-mediated dilation and aortic diameter has been performed in patients with bicuspid aortic valves and normal aortic diameters. Being a hereditary disease, we compared echocardiographic features and endothelial function in these patients and their first-degree relatives. Methods Comprehensive physical examinations, routine laboratory tests, transthoracic echocardiography, and measurements of endothelium-dependent and non-dependent flow-mediated vasodilatation were performed in 18 bicuspid aortic valve patients (14 type 1 and 4 type 2) and 19 of their first-degree relatives. Results The first-degree relatives were younger (36.7 ± 18.8 vs. 50.5 ± 13.9 years, p = 0.019) with higher ejection fractions (64.6% ± 1.7% vs. 58.4% ± 9.5%, p = 0.015). Aortic diameters indexed to body surface area were similar in both groups, the except the tubular aorta which was larger in bicuspid aortic valve patients (19.3 ± 2.7 vs. 17.4 ± 2.2 mm·m(-2), p = 0.033). Flow-dependent vasodilation was similar in both groups. A significant inverse correlation was found between non-flow-dependent vasodilation and aortic root diameter in patients with bicuspid aortic valve ( R = -0.57, p = 0.05). Conclusions Bicuspid aortic valve patients without aortopathy have larger ascending aortic diameters than their first-degree relatives. Endothelial function is similar in both groups, and there is no correlation with ascending aorta diameter. Nonetheless, an inverse correlation exists between non-endothelial-dependent dilation and aortic root diameter in bicuspid aortic valve patients.

  17. Aortic Dissection in Patients With Bicuspid Aortic Valve–Associated Aneurysms

    PubMed Central

    Wojnarski, Charles M.; Svensson, Lars G.; Roselli, Eric E.; Idrees, Jay J.; Lowry, Ashley M.; Ehrlinger, John; Pettersson, Gösta B.; Gillinov, A. Marc; Johnston, Douglas R.; Soltesz, Edward G.; Navia, Jose L.; Hammer, Donald F.; Griffin, Brian; Thamilarasan, Maran; Kalahasti, Vidyasagar; Sabik, Joseph F.; Blackstone, Eugene H.; Lytle, Bruce W.

    2016-01-01

    Background Data regarding the risk of aortic dissection in patients with bicuspid aortic valve and large ascending aortic diameter are limited, and appropriate timing of prophylactic ascending aortic replacement lacks consensus. Thus our objectives were to determine the risk of aortic dissection based on initial cross-sectional imaging data and clinical variables and to isolate predictors of aortic intervention in those initially prescribed serial surveillance imaging. Methods From January 1995 to January 2014, 1,181 patients with bicuspid aortic valve underwent cross-sectional computed tomography (CT) or magnetic resonance imaging (MRI) to ascertain sinus or tubular ascending aortic diameter greater than or equal to 4.7 cm. Random Forest classification was used to identify risk factors for aortic dissection, and among patients undergoing surveillance, time-related analysis was used to identify risk factors for aortic intervention. Results Prevalence of type A dissection that was detected by imaging or was found at operation or on follow-up was 5.3% (n = 63). Probability of type A dissection increased gradually at a sinus diameter of 5.0 cm—from 4.1% to 13% at 7.2 cm—and then increased steeply at an ascending aortic diameter of 5.3 cm—from 3.8% to 35% at 8.4 cm—corresponding to a cross-sectional area to height ratio of 10 cm2/m for sinuses of Valsalva and 13 cm2/m for the tubular ascending aorta. Cross-sectional area to height ratio was the best predictor of type A dissection (area under the curve [AUC] = 0.73). Conclusions Early prophylactic ascending aortic replacement in patients with bicuspid aortic valve should be considered at high-volume aortic centers to reduce the high risk of preventable type A dissection in those with aortas larger than approximately 5.0 cm or with a cross-sectional area to height ratio greater than approximately 10 cm2/m. PMID:26209494

  18. Increased aortic tortuosity indicates a more severe aortic phenotype in adults with Marfan syndrome.

    PubMed

    Franken, Romy; El Morabit, Abdelali; de Waard, Vivian; Timmermans, Janneke; Scholte, Arthur J; van den Berg, Maarten P; Marquering, Henk; Planken, Nils R N; Zwinderman, Aeilko H; Mulder, Barbara J M; Groenink, Maarten

    2015-09-01

    Patients with Marfan syndrome (MFS) have a highly variable occurrence of aortic complications. Aortic tortuosity is often present in MFS and may help to identify patients at risk for aortic complications. 3D-visualization of the total aorta by MR imaging was performed in 211 adult MFS patients (28% with prior aortic root replacement) and 20 controls. A method to assess aortic tortuosity (aortic tortuosity index: ATI) was developed and reproducibility was tested. The relation between ATI and age, and body size and aortic dimensions at baseline was investigated. Relations between ATI at baseline and the occurrence of a clinical endpoint (aortic dissection, and/or aortic surgery) and aortic dilatation rate during 3 years of follow-up were investigated. ATI intra- and interobserver agreements were excellent (ICC: 0.968 and 0.955, respectively). Mean ATI was higher in 28 age-matched MFS patients than in the controls (1.92 ± 0.2 vs. 1.82 ± 0.1, p=0.048). In the total MFS cohort, mean ATI was 1.87 ± 0.20, and correlated with age (r=0.281, p<0.001), aortic root diameter (r=0.223, p=0.006), and aortic volume expansion rate (r=0.177, p=0.026). After 49.3 ± 8.8 months follow-up, 33 patients met the combined clinical endpoint (7 dissections) with a significantly higher ATI at baseline than patients without endpoint (1.98 ± 0.2 vs. 1.86 ± 0.2, p=0.002). Patients with an ATI>1.95 had a 12.8 times higher probability of meeting the combined endpoint (log rank-test, p<0.001) and a 12.1 times higher probability of developing an aortic dissection (log rank-test, p=0.003) compared to patients with an ATI<1.95. Increased ATI is associated with a more severe aortic phenotype in MFS patients. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Prevalence of Salmonella in flocks housed in enriched cages.

    PubMed

    Zongo, P; Ducrot, A; Burie, J-B; Beaumont, C

    2015-04-01

    Salmonellosis is a foodborne disease of humans and animals caused by infection with Salmonella. The aim of this paper is to improve a deterministic model (DM) and an individual-based model (IBM) with reference to Salmonella propagation in flocks of laying hens taking into account variations in hens housed in the same cage and to compare both models. The spatio-temporal evolution, the basic reproduction number, R 0, and the speed of wave propagation were computed for both models. While in most cases the DM allows summary of all the features of the model in the formula for computation of R 0, slight differences between individuals or groups may be observed with the IBM that could not be expected from the DM, especially when initial environmental contamination is very low and some cages may get rid of bacteria. Both models suggest that the cage size plays a role on the risk and speed of propagation of the bacteria, which should be considered when designing new breeding systems.

  20. Percutaneous balloon aortic valvuloplasty in the era of transcatheter aortic valve implantation: a narrative review

    PubMed Central

    Keeble, Thomas R; Khokhar, Arif; Akhtar, Mohammed Majid; Mathur, Anthony; Weerackody, Roshan; Kennon, Simon

    2016-01-01

    The role of percutaneous balloon aortic valvuloplasty (BAV) in the management of severe symptomatic aortic stenosis has come under the spotlight following the development of the transcatheter aortic valve implantation (TAVI) technique. Previous indications for BAV were limited to symptom palliation and as a bridge to definitive therapy for patients undergoing conventional surgical aortic valve replacement (AVR). In the TAVI era, BAV may also be undertaken to assess the ‘therapeutic response’ of a reduction in aortic gradient in borderline patients often with multiple comorbidities, to assess symptomatic improvement prior to consideration of definitive TAVI intervention. This narrative review aims to update the reader on the current indications and practical techniques involved in undertaking a BAV procedure. In addition, a summary of the haemodynamic and clinical outcomes, as well as the frequently encountered procedural complications is presented for BAV procedures conducted during both the pre-TAVI and post-TAVI era. PMID:28008354