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1

Endoscopically aided retroperitoneal placement of a lumboperitoneal shunt. Technical note.  

PubMed

The authors developed a method for retroperitoneal placement of a lumboperitoneal (LP) shunt with the aid of endoscopic monitoring. To perform this procedure, the patient is positioned laterally, the retroperitoneum is entered and dilated with a balloon through a small incision in the flank, and the space is maintained with CO2 insufflation. A peritoneal catheter is introduced into the cavity from the lumbar incision, through which the spinal catheter has been inserted. With the aid of a percutaneous nephroscope inserted in the cavity, the peritoneum is opened with endoscopically guided forceps through the manipulation channel. The shunt tube is then inserted into the pelvic peritoneum with the same forceps. Only two small skin incisions are needed for this method, and the shunt system is shorter compared with the conventional LP setup, which may lessen the risk of obstruction. This method is advantageous in patients who have undergone previous abdominal surgery, because it provides access to the peritoneum without concern for the presence of peritoneal adhesions. PMID:12593636

Kubo, Shigeki; Ueno, Masato; Takimoto, Hiroshi; Karasawa, Jun; Kato, Amami; Yoshimine, Toshiki

2003-02-01

2

Minimally-invasive treatment of communicating hydrocephalus using a percutaneous lumboperitoneal shunt*  

PubMed Central

Objective: To investigate the clinical value of a minimally-invasive treatment of communicating hydrocephalus using a percutaneous lumboperitoneal (LP) shunt. Method: The clinical and long-term follow-up data of 256 patients suffering from communicating hydrocephalus and undergoing percutaneous LP shunt during 1998 to 2008 were retrospectively analyzed. Results: After the follow-up, which lasted 6 months to 10 years, 219 cases of communicating hydrocephalus recovered well (ventricular size returned to normal and symptoms completely disappeared), 25 cases were brought under control (ventricle size reduced by 50% and symptoms partially abated), and 12 cases showed no obvious changes. Fifteen obese subjects needed modifications of the shunt due to the obstruction of the abdominal end following wrapping, and one subject underwent extubation as the subject was unable to tolerate stimulation of the cauda equina. The effectiveness of shunting was 91.40% and the probability of shunt-tube obstruction, which occurs predominantly in the abdominal end, was only 5.85%, far lower than that of ventriculoperitoneal (VP) shunt. Three subjects had a history of infection following VP shunting. Conclusion: LP shunting is minimally invasive and effective in treating communicating hydrocephalus, with fewer complications. PMID:21462385

Jia, Lu; Zhao, Zhong-xin; You, Chao; Liu, Jia-gang; Huang, Si-qing; He, Min; Ji, Pei-gang; Duan, Jie; Zeng, Yi-jun; Li, Guo-ping

2011-01-01

3

Assessment lumboperitoneal or ventriculoperitoneal shunt patency by radionuclide technique: a review experience cases.  

PubMed

Hydrocephalus-related symptoms that worsen after shunt placement may indicate a malfunctioning or obstructed shunt. The assessment of shunt patency and site of obstruction is important for planning of treatment. The radionuclide cerebrospinal fluid (CSF) shunt study provides a simple, effective, and low-radiation-dose method of assessing CSF shunt patency. The radionuclide CSF shuntography is a useful tool in the management of patients presenting with shunt-related problems not elucidated by conventional radiological examination. This article described the imaging technique of ventriculoperitoneal (VP) shunt and lumbar puncture (LP) shunt. The normal finding, abnormal finding of completed obstruction and partial obstruction is present by our cases experience. The radiopharmaceutical (Tc-99m diethylenetriaminepentaacetic acid) was injected via the reservoir for VP shunt and via lumbar puncture needle in subarachnoid space for LP shunt, then serial image in the head and abdominal area. The normal function of VP and LP shunt usually rapid spillage of the radioactivity in the abdominal cavity diffusely. The patent proximal tube VP shunt demonstrates ventricular reflux. The early image of patent LP shunt reveals no activity in the ventricular system contrast to distal LP shunt reveals early reflux of activity in the ventricular system. The completed distal VP and LP shunt obstruction show absence of tracer in the peritoneal area or markedly delayed appearance of abdominal activity. The partial distal VP and LP shunt obstruction recognized by slow transit or accumulation of tracer at the distal end or focal tracer in the peritoneal cavity near the tip of distal shunt. The images of the normal and abnormal CSF shunt as describe before are present in the full paper. Radionuclide CSF shuntography is a reliable and simple procedure for assessment shunt patency. PMID:25191120

Chiewvit, Sunanta; Nuntaaree, Sarun; Kanchaanapiboon, Potjanee; Chiewvit, Pipat

2014-05-01

4

Use of blunt scalp hooks for abdominal procedure in lumboperitoneal shunt placement: technical note.  

PubMed

In obese patients, we often find difficulty in laparotomy for placing a lumboperitoneal shunt catheter. The authors introduced an easy technique to get a sufficiently wide and shallow operative field through small abdominal incision in obese people. Four blunt scalp hooks and rubber bands, commonly used in craniotomy, were prepared. The fat layer and the rectus abdominis muscle layer were retracted and pulled up using these hooks. Blunt scalp hooks were useful for safe and effective retraction of abdominal wall, which made a sufficient and shallow operative field. PMID:24759096

Kawahara, Takashi; Higashi, Takuichiro; Tokimura, Hiroshi; Arita, Kazunori; Atsuchi, Masamichi; Takasaki, Koji

2014-01-01

5

Rapid Recovery of Visual Acuity after Lumboperitoneal Shunt Operation in Malignant Idiopathic Intracranial Hypertension  

PubMed Central

Background. Idiopathic intracranial hypertension can cause rapid deterioration of visual acuity in some severe cases, and these cases are usually thought to have “malignant” form of this disease. Case. In this paper, we report on a 16-year-old girl who is a typical example for malignant idiopathic intracranial hypertension with a rapid recovery of visual acuity after lumboperitoneal shunt operation. Observations and Conclusions. Malignant form of idiopathic intracranial hypertension must be kept in mind in selected patients to avoid irreversible visual loss. PMID:22606459

Bir, Levent Sinan; Degirmenci, Eylem; Erdogan, Cagdas; Bilgin, Selma; Co?kun, Erdal

2011-01-01

6

Abdominal wall endometriosis associated with ventriculoperitoneal and lumboperitoneal shunts: a report of 2 cases of an extremely rare phenomenon.  

PubMed

Endometriosis is a common condition in women of reproductive age and has a known propensity to involve abdominal wall scars. The authors report 2 cases of endometriosis presenting as mass lesions involving the abdominal wall at the site of insertion of ventriculoperitoneal and lumboperitoneal shunts. In both cases, there was clinical evidence of shunt compromise. Endometriosis involving the site of shunt insertion is an extremely rare phenomenon with, as far as the authors are aware, only a single previously reported case. However, it should be considered in the differential diagnosis when a mass develops at a shunt site in a woman of reproductive age. PMID:21997593

Healy, Estelle G; McCluggage, W Glenn

2012-06-01

7

Spinal Intradural Hematoma and Permanent Paraparesis after a Lumboperitoneal Shunt Operation: An Unusual Complication  

PubMed Central

Pseudotumor cerebri is a condition of increased intracranial pressure in the absence of clinical, laboratory or radiological pathology. Spinal intradural hematoma formation after lumboperitoneal shunt (LPS) implantation is very rare, but it can cause sudden and serious deterioration. In this report, we present a patient who developed an intradural hematoma following LPS operation. A 27-year-old male patient suffering from headaches and progressive vision loss was diagnosed with pseudotumor cerebri. He underwent LPS operation in January 2009. Four hours after the operation, he developed urinary and fecal incontinence with paraparesis (1/5). Lumbar magnetic resonance imaging identified an intradural hematoma at the level of L2-L3, and he was reoperated. The intradural hematoma was removed. Physical therapy was started because of paraparesis. Two months later, the patient's muscle strength had increased to 3/5. Surgeons must remember that, LPS implantation can cause a spinal intradural hematoma in a small percentage of patients, with catastrophic results. PMID:25187872

Efendioglu, Mustafa; Bolukbasi, Fatih Han; Aslan, Sahin; Isik, Nejat; Kaner, Tuncay

2014-01-01

8

Spinal intradural hematoma and permanent paraparesis after a lumboperitoneal shunt operation: an unusual complication.  

PubMed

Pseudotumor cerebri is a condition of increased intracranial pressure in the absence of clinical, laboratory or radiological pathology. Spinal intradural hematoma formation after lumboperitoneal shunt (LPS) implantation is very rare, but it can cause sudden and serious deterioration. In this report, we present a patient who developed an intradural hematoma following LPS operation. A 27-year-old male patient suffering from headaches and progressive vision loss was diagnosed with pseudotumor cerebri. He underwent LPS operation in January 2009. Four hours after the operation, he developed urinary and fecal incontinence with paraparesis (1/5). Lumbar magnetic resonance imaging identified an intradural hematoma at the level of L2-L3, and he was reoperated. The intradural hematoma was removed. Physical therapy was started because of paraparesis. Two months later, the patient's muscle strength had increased to 3/5. Surgeons must remember that, LPS implantation can cause a spinal intradural hematoma in a small percentage of patients, with catastrophic results. PMID:25187872

Basaran, Recep; Efendioglu, Mustafa; Bolukbasi, Fatih Han; Aslan, Sahin; Isik, Nejat; Kaner, Tuncay

2014-08-01

9

Change of patient position using a transportation board during lumboperitoneal shunting. Technical note.  

PubMed

Lumboperitoneal shunt placement requires access to the lumbar theca in the lateral position, followed by subsequent laparotomy in the supine position. This position change and repeat draping are bothersome, especially in heavy patients, so we developed a method that facilitates changing the patient position while keeping the surgical drapes in place. An oblong plastic board covered with Teflon-coated glassfiber cloth and surrounded by a nylon-cloth sleeve is used. The sleeve can be easily moved over the board, so patients can be moved in the transverse direction with minimal pushing force. The patient is placed in the lateral position on the board on the operating table and draped from the back to the abdomen. After catheter insertion into the lumbar theca and introduction of a subcutaneous tunnel to the flank, the patient is pushed in the ventral direction, moved to the opposite edge of the operating table, and the position is changed from lateral to supine, leaving the original drape intact. Finally, a catheter is placed by laparotomy. We were able to change position easily in 20 patients weighing 47-85 kg (mean 69.6 kg). This technique reduces the labor required for position change and preserves sterility. PMID:19398864

Shimizu, Satoru; Hagiwara, Hiroyuki; Hattori, Satoshi; Nakayama, Kenji; Fujii, Kiyotaka

2009-04-01

10

Controversies: Optic nerve sheath fenestration versus shunt placement for the treatment of idiopathic intracranial hypertension  

PubMed Central

Background: Idiopathic intracranial hypertension (IIH) has been increasing in prevalence in the past decade, following the obesity epidemic. When medical treatment fails, surgical treatment options must be considered. However, controversy remains as to which surgical procedure is the preferred surgical option – optic nerve sheath fenestration (ONSF) or cerebrospinal fluid (CSF) shunting – for the long-term treatment of this syndrome. Purpose: To provide a clinical update of the pros and cons of ONSF versus shunt placement for the treatment of IIH. Design: This was a retrospective review of the current literature in the English language indexed in PubMed. Methods: The authors conducted a PubMed search using the following terms: Idiopathic IIH, pseudotumor cerebri, ONSF, CSF shunts, vetriculo-peritoneal shunting, and lumbo-peritoneal shunting. The authors included pertinent and significant original articles, review articles, and case reports, which revealed the new aspects and updates in these topics. Results: The treatment of IIH remains controversial and lacks randomized controlled clinical trial data. Treatment of IIH rests with the determination of the severity of IIH-related visual loss and headache. Conclusion: The decision for ONSF versus shunting is somewhat institution and surgeon dependent. ONSF is preferred for patients with visual symptoms whereas shunting is reserved for patients with headache. There are positive and negative aspects of both procedures, and a prospective, randomized, controlled trial is needed (currently underway). This article will hopefully be helpful in allowing the reader to make a more informed decision until that time. PMID:25449938

Spitze, Arielle; Lam, Peter; Al-Zubidi, Nagham; Yalamanchili, Sushma; Lee, Andrew G

2014-01-01

11

Ventriculoperitoneal shunt - discharge  

MedlinePLUS

Shunt - ventriculoperitoneal - discharge; VP shunt - discharge; Shunt revision - discharge ... cranky or irritable Redness, swelling, bleeding, or increased discharge from the incision Vomiting that does not go ...

12

Complications of Ventricular Shunts  

Microsoft Academic Search

Ventricular shunting is the most widely accepted form of treatment of hydrocephalus. The placement of cerebrospinal fluid shunts has become on eo f the most common procedures in modern neurologic surgery. Despite significant improve- ments in shunt procedures, shunt complications remain common. These troubles are associated with significant adverse consequences, both medical and economic. At- tempts to limit their incidence

Bradley E. Weprin; Dale M. Swift

2002-01-01

13

Cryptococcal ventriculoperitoneal shunt infection.  

PubMed

The standard treatment of hydrocephalus is placement of a ventriculoperitoneal (VP) shunt. While infection is a common complication, rarely are fungal organisms implicated. Cryptococcus neoformans has been reported in only nine cases of shunt infection to our knowledge. The timing from shunt placement to symptom onset varies widely from 10 days to 15 months. We present a patient who developed a cryptococcal infection of his VP shunt more than two decades following shunt placement. PMID:25220283

Viereck, Matthew J; Chalouhi, Nohra; Krieger, David I; Judy, Kevin D

2014-11-01

14

Reflections on shunt infection.  

PubMed

The placement and revision of ventriculoperitoneal (VP) shunts remains a mainstay in the surgical treatment of hydrocephalus. While the North American infection rate averages nearly 8-10%, published infection rates for VP shunt infection below 1% have been reported. We retrospectively reviewed shunt operations by a single surgeon over 62 months to analyze the infection rate. In 62 months, we performed 526 shunt placements or revisions in patients up to 18 years of age. There were 7 shunt infections (1.33%). In 5 cases, the organism was Staphylococcus epidermidis, and a single shunt each was infected with Haemophilus influenzae and Staphylococcus aureus. Each infection was treated with external ventriculostomy drainage and intravenous antibiotics. The new shunt was placed at a new incision site after at least 5 days of sterile spinal fluid cultures. The mean follow-up among these patients after shunt insertion was 25 months. VP shunting remains the most common operation for hydrocephalus. Infections are linked with seizures, higher future risks of shunt infection and malfunction, and reduced IQ and school performance. Our infection rate during 62 months was limited to 1.33%. Uniform surgical technique, limited hardware and skin edge manipulation and double gloving may be important factors in limiting shunt infections. PMID:14734861

Kanev, Paul M; Sheehan, Jonas M

2003-12-01

15

Aqueous shunts for glaucoma  

PubMed Central

Background Aqueous shunts are employed for intraocular pressure (IOP) control in primary and secondary glaucomas that fail medical, laser, and other surgical therapies. Objectives This review compares aqueous shunts for IOP control and safety. Search strategy We searched CENTRAL, MEDLINE, PubMed, EMBASE, NRR in January 2006, LILACS to February 2004 and reference lists of included trials. Selection criteria We included all randomized and quasi-randomized trials in which one arm of the study involved shunts. Data collection and analysis Two authors independently extracted data for included studies and a third adjudicated discrepancies. We contacted investigators for missing information. We used fixed-effect models and summarized continuous outcomes using mean differences. Main results We included fifteen trials with a total of 1153 participants with mixed diagnoses. Five studies reported details sufficient to verify the method of randomization but only two had adequate allocation concealment. Data collection and follow-up times were variable. Meta-analysis of two trials comparing Ahmed implant with trabeculectomy found trabeculectomy resulted in lower mean IOPs 11 to 13 months later (mean difference 3.81 mm Hg, 95% CI 1.94 to 5.69 mm Hg). Meta-analysis of two trials comparing double-plate Molteno implant with the Schocket shunt was not done due to substantial heterogeneity. One study comparing ridged with standard double-plate Molteno implants found no clinically significant differences in outcome. Two trials investigating the effectiveness of adjunctive mitomycin (MMC) with the Molteno and Ahmed implants found no evidence of benefit with MMC. Two trials that investigated surgical technique variations with the Ahmed found no benefit with partial tube ligation or excision of Tenon's capsule. One study concluded there were outcome advantages with a double versus a single-plate Molteno implant and one trial comparing the 350 mm2 and 500 mm2 Baerveldt shunts found no clinically significant advantage of the larger device but neither of these trials included all patients randomized. One study suggested improved clinical outcome when MMC was employed with a newly described shunt including ultrasound supporting the conclusion. One small study did not demonstrate an outcome advantage to systemic steroid use postoperatively with single-plate Molteno shunts. One study comparing endocyclophotocoagulation (ECP) with Ahmed implant in complicated glaucomas found no evidence of better IOP control with Ahmed implant over ECP. Authors' conclusions Relatively few randomized trials have been published on aqueous shunts and methodology and data quality among them is poor. To date there is no evidence of superiority of one shunt over another. PMID:16625616

Minckler, Don; Vedula, Satyanarayana S; Li, Tianjing; Mathew, Milan; Ayyala, Ramesh; Francis, Brian

2014-01-01

16

residue and shunting pinholes  

NASA Astrophysics Data System (ADS)

The present work considers two observable phenomena through the experimental fabrication and electrical characterization of the rf-sputtered CdS/CdTe thin film solar cells that extremely reduce the overall conversion efficiency of the device: CdCl2 residue on the surface of the semiconductor and shunting pinholes. The former happens through nonuniform treatment of the As-deposited solar cells before annealing at high temperature and the latter occurs by shunting pinholes when the cell surface is shunted by defects, wire-like pathways or scratches on the metallic back contact caused from the external contacts. Such physical problems may be quite common in the experimental activities and reduce the performance down to 4-5 % which leads to dismantle the device despite its precise fabrication. We present our electrical characterization on the samples that received wet CdCl2 surface treatment (uniform or nonuniform) and are damaged by the pinholes.

Gorji, Nima E.

2014-09-01

17

Transjugular Intrahepatic Portosystemic Shunt.  

PubMed

Transjugular intrahepatic portosystemic shunt (TIPS) is an established procedure for the complications of portal hypertension. The largest body of evidence for its use has been supported for recurrent or refractory variceal bleeding and refractory ascites. Its use has also been advocated for acute variceal bleed, hepatic hydrothorax, and hepatorenal syndrome. With the replacement of bare metal stents with polytetrafluoroethylene-covered stents, shunt patency has improved dramatically, thus, improving outcomes. Therefore, reassessment of its utility, management of its complications, and understanding of various TIPS techniques is important. PMID:25438287

Patidar, Kavish R; Sydnor, Malcolm; Sanyal, Arun J

2014-11-01

18

Transjugular intrahepatic portosystemic shunt.  

PubMed

The transjugular intrahepatic portosystemic shunt (TIPS) is an interventional treatment resulting in decompression of the portal system by creation of a side-to-side portosystemic anastomosis. Since its introduction 16 years ago, more than 1,000 publications have appeared demonstrating broad acceptance and increasing clinical use. This review summarizes our present knowledge about technical aspects and complications, follow-up of patients and indications. A technical success rate near 100% and a low occurrence of complications clearly depend on the skills of the operator. The follow-up of the TIPS patient has to assess shunt patency, liver function, hepatic encephalopathy and the possible development of hepatocellular carcinoma. Shunt patency can best be monitored by duplex sonography and can avoid routine radiological revision. Short-term patency may be improved by anticoagulation, while such a treatment does not influence long-term patency. Stent grafts covered with expanded polytetrafluoroethylene show promising long-term patency comparable with that of surgical shunts. With respect to the indications of TIPS, much is known about treatment of variceal bleeding and refractory ascites. The thirteen randomized studies that are available to date show that survival is comparable in patients receiving TIPS or endoscopic treatment for acute or recurrent variceal bleeding. Another group comprises patients with refractory ascites and related complications, such as hepatorenal syndrome and hepatic hydrothorax. It has been demonstrated that TIPS improves these complications. Five randomized studies comparing TIPS with paracentesis and one study comparing TIPS with the peritoneo-venous shunt showed good response of ascites but controversial results on survival. In addition, TIPS has been successfully applied to patients with Budd-Chiari syndrome, portal vein thrombosis, before liver transplantation, and for the treatment of ectopic variceal bleeding. PMID:15920326

Ochs, Andreas

2005-01-01

19

[Simplfied technique of lumbar subarachnoid-peritoneal shunt (author's transl)].  

PubMed

The authors have developed a simplified technique of lumbar subarachnoid peritoneal shunt in which the spinal tube is easily introduced through a puncture needle without doing a laminectomy. Seventeen cases of communicating hydrocephalus of various orgin have been treated by this procedure. In this paper, we reported our shunting system and the technique of precedures, and discussed the clinical results and some advantages of this method. The spinal tube is a custom made Silastic tube with small side holes 2 mm apart from each other at slanting tip located within the first 1.0 cm of the end. French No. 5 tube is available for older children and for adults, and French No. 3.6 tube for infants. Total length of the tube measures 30 cm with 4 black markers at 5 cm intervals from the tip for assisting in positioning. The puncture needle is a modified Touhey needle. Two needles different in size are prepared according to the size of the tube. Outer diameter of these needles is 2.1 mn & 1.8 mn. Our operative procedures are divided into following three steps. 1) Puncture of the lumbar subarachnoid space and insertion of the spinal tube through the needle. 2) Introduction and placement of the peritoneal tube into some point of the peritoneal cavity. Concerning to this point, we have the three candidates, namely into the Douglas pouch, the suprahepatic space, and the bursa omental cavity. 3) Connection of the spinal tube and the peritoneal catheter end. We used a kind of flushing device only in some exceptional cases, and recently, we feel that it is not so necessary for this shunting. We have employed this technique in a total of 17 cases. Eleven cases of them are adults and the other 6 cases are children less than 2 years of age. Postoperative follow up period varied from 13 months to 1 month, and all the cases except two had good result, suggesting the shunt system is working well with no evidence of complications such as low pressure syndrome or radicular irritation. Some troubles occurred in two children. One was a disconnection between the spinal and the peritoneal tube, and the other was an obstruction at the peritoneal tube end. The authors believe that our L-P shunt has several advantages as listed below, 1)Procedure is very simple, in other words, there is no need of laminectomy. 2) The entire system is short. 3) No need to pass the catheter into the brain tissue. 4) Obstruction of the spinal catheter end is very unusual. 5) Alteration of communicating hydrocepalus into non communicating one by secondary obstruction of aqueduct of Sylvius is less likely with this shunting system. 6) Siphon effect might be minimal, if present. 7) As compared to V-A shunt, severe complication like septicemia will not occur in the L-P shunt. With this simple method and good material, we hope that this L-P shunt is employed more widely for the patients with communicating hydrocephalus. PMID:557743

Kuwana, N; Kuwabara, T; Nakajima, F; Hosoda, H; Yamaguchi, K

1977-03-01

20

Shunt dependence: myths and facts  

Microsoft Academic Search

Introduction  Chronically shunted patients are believed to be unable to have a shunt-free life. Nevertheless, sometimes shunt removal is\\u000a possible after an endoscopic third ventriculostomy, even after long periods of cerebral spinal fluid diversion.\\u000a \\u000a \\u000a \\u000a \\u000a Results and discussion  We perform a literature review that leads to a discussion of this subject in the light of the current medical knowledge.

Igor Lima Maldonado; Charles-Ambroise Valery; Anne-Laure Boch

2010-01-01

21

LP-80 IMU program status  

NASA Astrophysics Data System (ADS)

Development history, system design features, performance, and hardware status are reviewed for the fourth-generation LP-80 strapdown inertial measurement unit (IMU) which is currently in full-scale development to meet the design objectives required for missiles, torpedoes, drones, and range instrumentation system applications. The LP-80 is fully self-contained and operates at all attitudes, providing digital processed outputs of angular rate and linear acceleration measured in the body axis frame. For range applications, the LP-80 is designed to provide linear velocities with respect to a space stabilized coordinate frame.

Jackson, Edward N.

22

Registration of LP1-2581, LP1-2163H, LP3-1159, and LP640-1304 low phytate spring barley germplasm lines  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Agricultural Research Service, U.S. Dept. of Agriculture (USDA-ARS) has developed and released four low-phytate spring barley (Hordeum vulgare L.) germplasm lines: LP1-2581 (Reg. No._____, PI 658245), LP1-2163H (Reg. No._____, PI 658248 ), LP3-1159 (Reg. No._____, PI 658247), and LP640-1304 (...

23

49 CFR 234.229 - Shunting sensitivity.  

Code of Federal Regulations, 2012 CFR

... 4 2012-10-01 2012-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other...Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail grade crossing train detection...

2012-10-01

24

49 CFR 234.229 - Shunting sensitivity.  

Code of Federal Regulations, 2010 CFR

... 4 2010-10-01 2010-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other...Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail grade crossing train detection...

2010-10-01

25

49 CFR 234.229 - Shunting sensitivity.  

Code of Federal Regulations, 2011 CFR

... 4 2011-10-01 2011-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other...Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail grade crossing train detection...

2011-10-01

26

49 CFR 234.229 - Shunting sensitivity.  

Code of Federal Regulations, 2013 CFR

... 4 2013-10-01 2013-10-01 false Shunting sensitivity. 234.229 Section 234.229 Transportation Other...Testing Maintenance Standards § 234.229 Shunting sensitivity. Each highway-rail grade crossing train detection...

2013-10-01

27

Leaf Senescence and GABA Shunt  

PubMed Central

Leaf senescence is highly regulated and complex developmental process that involves degradation of macromolecules as well as its recycling. Senescence process involves loss of chlorophyll, degradation of proteins, nucleic acid, lipid and mobilization of nutrients through its transport to the growing parts, developing fruits and seeds. Nitrogen is the most important nutrient to be recycled in senescence process. GABA-transaminase (?-aminobutyric acid) is found to play very important role in nitrogen recycling process through GABA-shunt. Therefore, it is of interest to review the significance of GABA shunt in leaf senescence.

Ansari, Mohammad Israil; Hasan, Saba; Jalil, Syed Uzma

2014-01-01

28

WEIGHTED Lp -BOUNDEDNESS OF FOURIER SERIES  

E-print Network

Jacobi weight on the interval [-1, 1] and, for each function f, let Snf denote the n-th partial sum with respect to dµ. The study of the boundedness Snf Lp(updµ) C f Lp(vpdµ), (1) where u(x) = (1 - x)a (1 + x, . . . , N) (3) and A a, B b, Gi gi (4) hold, then C > 0 such that Snf Lp(updµ) C f Lp(vpdµ) f Lp (vp dµ

Pérez, Mario

29

Endoscopic third ventriculostomy for shunt malfunction: What to do with the shunt?  

PubMed Central

Background: Endoscopic third ventriculostomy (ETV) is an effective surgical option for the treatment of shunt malfunction. The role of postoperative cerebrospinal fluid (CSF) diversion is not clearly understood at this time. We compare the effects of shunt-removal/ligation, shunt externalization or external ventricular drain placement, and no treatment to the indwelling shunt at the time of ETV. Methods: We retrospectively reviewed the records of 20 consecutive patients treated at our institution for shunt malfunction with ETV. Patient data were retrospectively evaluated for the effect that the fate of the shunt plays on ETV success rates. Results: In our series of 20 patients we had an overall success rate of 70% with using ETV for shunt malfunction. Patients who had their shunts ligated at the time of surgery had a success rate of 88%, in comparison to those whom the shunt was left untouched who had a success rate of 60%, or patients who had a perioperative external ventricular drain placed the success rate was 50%. Conclusions: This series of ETV for shunt malfunction performed at a single center by a single surgeon shows a success rate similar to the published literature range of 67 to 80 percent success whether the shunt is ligated or left undisturbed. It is not necessary to ligate the in situ shunt at the time of ETV; however, there may be a trend toward an improved success rate with shunt ligation. Further studies with a greater numbers of patients are warranted. PMID:23493502

Neils, David M.; Wang, Huaping; Lin, Julian

2013-01-01

30

Arterioportal shunts on dynamic computed tomography  

SciTech Connect

Thirty-two patients, 20 with hepatocelluar carcinoma and 12 with liver cirrhosis, were examined by dynamic computed tomography (CT) using intravenous bolus injection of contrast medium and by celiac angiography. Dynamic CT disclosed arterioportal shunting in four cases of hepatocellular carcinoma and in one of cirrhosis. In three of the former, the arterioportal shunt was adjacent to a mass lesion on CT, suggesting tumor invasion into the portal branch. In one with hepatocellular carcinoma, the shunt was remote from the mass. In the case with cirrhosis, there was no mass. In these last two cases, the shunt might have been caused by prior percutaneous needle puncture. In another case of hepatocellular carcinoma, celiac angiography but not CT demonstrated an arterioportal shunt. Thus, dynamic CT was diagnostic in five of six cases of arteriographically demonstrated arterioportal shunts.

Nakayama, T.; Hiyama, Y.; Ohnishi, K.; Tsuchiya, S.; Kohno, K.; Nakajima, Y.; Okuda, K.

1983-05-01

31

Urinary Bladder Stone Complicating Ventriculovesical Shunt  

PubMed Central

The standard treatment for hydrocephalus is either a ventriculoperitoneal or a ventriculo-atrial shunt. However, these conventional shunts may be associated with considerable complications and high revision rates which make these familiar shunts inappropriate for a certain subset of patients. A rare complication is reported associated with an unusual procedure in a 42-year-old woman who had had a ventriculovesical shunt for four years. She presented with recurrent urinary tract infections, haematuria and urge incontinence, and was discovered to have a large vesical stone over the vesical end of the shunt. She was treated with open suprapubic cystolithotomy and the redirection of the shunt to the peritoneal cavity. The patient was followed up for 12 months postoperatively and remained free of any urinary tract symptoms. PMID:24516748

Ibrahim, Ahmed K.

2014-01-01

32

Histopathologic study of transjugular intrahepatic portosystemic shunts.  

PubMed

A detailed histopathologic analysis of intrahepatic portosystemic shunts was performed following liver transplantation in five patients. Gross examination revealed that all stents were patent and unchanged in size, shape, and position from initial placement. Histologic examination at 4 days revealed an irregular luminal surface with liver parenchyma protruding between the stent wires and a single, patchy layer of endothelial cells lining the shunt surface. By 3 weeks, the stent wires were covered by a pseudointima of granulation tissue, and the luminal surface was lined with a contiguous layer of endothelial cells. Excessive pseudointimal proliferation resulted in shunt occlusion at 3 months in one patient whose shunt was subsequently reopened percutaneously. PMID:1797223

LaBerge, J M; Ferrell, L D; Ring, E J; Gordon, R L; Lake, J R; Roberts, J P; Ascher, N L

1991-11-01

33

Percutaneous Portosystemic Shunts: TIPS and Beyond.  

PubMed

Percutaneous interventions for portal hypertension have been available since the 1990s. Over time, improved technology-including covered stent grafts-and clinical understanding has expanded the available procedures for percutaneous portal decompression. While transjugular intrahepatic portosystemic shunt creation is the most commonly cited percutaneous intervention, direct intrahepatic portocaval shunt and percutaneous mesocaval shunt creation are important alternatives with specific advantages and applications. This article reviews contemporary, minimally invasive interventional approaches to percutaneous portosystemic shunt creation in terms of procedure rationale, patient selection, interventional technique, and technical outcomes. PMID:25177082

Casadaban, Leigh C; Gaba, Ron C

2014-09-01

34

49 CFR 236.60 - Switch shunting circuit; use restricted.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Switch shunting circuit; use restricted. 236.60 Section 236...Rules and Instructions: All Systems Track Circuits § 236.60 Switch shunting circuit; use restricted. Switch shunting...

2012-10-01

35

49 CFR 236.60 - Switch shunting circuit; use restricted.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Switch shunting circuit; use restricted. 236.60 Section 236...Rules and Instructions: All Systems Track Circuits § 236.60 Switch shunting circuit; use restricted. Switch shunting...

2010-10-01

36

49 CFR 236.60 - Switch shunting circuit; use restricted.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Switch shunting circuit; use restricted. 236.60 Section 236...Rules and Instructions: All Systems Track Circuits § 236.60 Switch shunting circuit; use restricted. Switch shunting...

2013-10-01

37

49 CFR 236.725 - Circuit, switch shunting.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Circuit, switch shunting. 236.725 Section 236...AND APPLIANCES Definitions § 236.725 Circuit, switch shunting. A shunting circuit which is closed through contacts of a...

2013-10-01

38

49 CFR 236.60 - Switch shunting circuit; use restricted.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Switch shunting circuit; use restricted. 236.60 Section 236...Rules and Instructions: All Systems Track Circuits § 236.60 Switch shunting circuit; use restricted. Switch shunting...

2011-10-01

39

Infrared thermography for control of hemodialysis shunts  

Microsoft Academic Search

Hemodialysis through an arteriovenous (AV) fistula remains the most frequent treatment of terminal renal insufficiency until renal transplantation. In case of malfunction of the shunt colour coded duplex sonography or angiography are used for investigation. The authors tried to evaluate the technical feasibility of infrared thermography for control of hemodialysis shunts. 27 consecutive patients who were planned for duplex sonographic

T. Maca; S. Schmaldienst; M. Atteneder; S. Fasching; W. H. Horl; R. Katzenschlager; E. Knespel; I. Koppensteiner; R. Koppensteiner; A. Ugurluoglu; A. Willfort; H. Ehringer

1997-01-01

40

Hepatic Blood Flow after Canine Portasystemic Shunting  

PubMed Central

Effects of portasystemic shunting on total hepatic blood flow (THBF) were evaluated in mongrel dogs with 35 and 50µ radioactive microspheres. THBF was measured prior to shunting and 1 hour and 3 weeks after surgery. Using systemic and pulmonary artery catheters, pertinent hemodynamic variables were also measured. In sham-operated dogs (n = 5), there were no significant changes in the hemodynamic parameters or the components of THBF during the experiment. After end-to-side shunting (n = 7), animals experienced a significant, permanent fall in hepatopetal portal blood flow (HABF). In contrast, dogs with side-to-side shunts (n = 7) exhibited a transient, significant increase in HABF 1 hour after surgery. Although the shunt eliminated HPBF, the rise in HABF prevented a significant, immediate fall in THBF. Three weeks after surgery, however, HABF had returned to the baseline range, and THBF was significantly lower than the preshunt value. Dogs with H-graft mesocaval shunts (n = 5) also exhibited a transient, significant rise in HABF 1 hour after surgery. Since HPBF did not fall substantially, THBF at this time was significantly higher than the baseline value. Three weeks after surgery, HABF had fallen to the baseline range, but THBF was not significantly different from the preshunt level. In animals with distal splenorenal shunts (n = 11), there was no significant change in HABF after shunting. Both HPBF and THBF were transiently, significantly reduced immediately after surgery, but three weeks later neither parameter was significantly lower than the preshunt values. There were no significant, persistent changes in the systemic perfusion pressures or flows in the shunted groups. These experiments demonstrate that the reported increase in HABF following portasystemic shunting is dependent on the type of shunt and, if it occurs, is a transient phenomenon. Hence, immediate postoperative changes in hemodynamic variables or hepatic blood flows do not necessarily reflect long-term patterns. In the normal dog, total portasystemic shunting produces a permanent, significant decrease in THBF, whereas selective shunting maintains THBF in the near-normal range. PMID:7092366

Shatney, Clayton H.; Harmon, John W.; Rich, Norman M.

1982-01-01

41

Ventriculoperitoneal Shunt Peritoneal Catheter Knot Formation  

PubMed Central

The ventriculoperitoneal (VP) shunt is a common procedure in pediatric neurosurgery that carries a risk of complications at cranial and abdominal sites. We report on the case of a child with shunt infection and malfunction. The peritoneal catheter was tethered within the abdominal cavity, precluding its removal. Subsequently, laparoscopic exploration identified a knot at the distal end of the peritoneal catheter around the omentum. A new VP shunt was inserted after the infection was healed. This type of complication occurs rarely, so there are a limited number of case reports in the literature. This report is complemented by a literature review. PMID:24109528

Ul-Haq, Anwar; Al-Otaibi, Faisal; Alshanafey, Saud; Sabbagh, Mohamed Diya; Al Shail, Essam

2013-01-01

42

Scintisplenoportography in assessing patency of distal splenorenal shunts  

SciTech Connect

Scintisplenoportography was performed on 33 occasions in 28 cirrhotic patients who had bled from esophagogastric varices. In 17 cases scintisplenoportography was carried out after a retroperitoneal distal splenorenal shunt procedure and in the remaining 16 instances in patients without any surgical shunt. In four patients scintisplenoportography was performed before and after a surgical shunt procedure, and in one case, before and after the shunt thrombosed. Gammagraphic patterns and spleen-heart times helped determine which patients did not have a surgical shunt, which had a patent shunt, and which patients had a thrombosed shunt. A patent shunt pattern and a thrombosed shunt pattern have been defined. It is concluded that scintisplenoportography is a useful, reproducible, and safe method to assess the patency of distal splenorenal shunts.

Teres, J.; Herranz, R.; Visa, J.; Lomena, F.; Pera, C.; Rodes, J.

1983-06-01

43

Acute Shunt Malfunction Caused by Percutaneous Endoscopic Gastrostomy without Shunt Infection  

PubMed Central

Percutaneous endoscopic gastrostomy tube placement is often performed in patients with a ventriculoperitoneal shunt and it has been accepted as a safe procedure. The authors report a case of a 50-year-old male who developed acute exacerbation of the hydrocephalus immediately after the percutaneous endoscopic gastrostomy tube placement without any signs of shunt infection, which has not been reported until now. After revision of the intraperitoneal shunt catheter, the sizes of the intracranial ventricles were normalized. PMID:25371790

Choi, Jingyu; Ki, Seung Seog

2014-01-01

44

Acute Shunt Malfunction Caused by Percutaneous Endoscopic Gastrostomy without Shunt Infection.  

PubMed

Percutaneous endoscopic gastrostomy tube placement is often performed in patients with a ventriculoperitoneal shunt and it has been accepted as a safe procedure. The authors report a case of a 50-year-old male who developed acute exacerbation of the hydrocephalus immediately after the percutaneous endoscopic gastrostomy tube placement without any signs of shunt infection, which has not been reported until now. After revision of the intraperitoneal shunt catheter, the sizes of the intracranial ventricles were normalized. PMID:25371790

Choi, Jingyu; Ki, Seung Seog; Park, Seoungwoo

2014-10-01

45

Endoscopic Third Ventriculostomy in Previously Shunted Children  

PubMed Central

Endoscopic third ventriculostomy (ETV) is a routine and safe procedure for therapy of obstructive hydrocephalus. The aim of our study is to evaluate ETV success rate in therapy of obstructive hydrocephalus in pediatric patients formerly treated by ventriculoperitoneal (V-P) shunt implantation. From 2001 till 2011, ETV was performed in 42 patients with former V-P drainage implantation. In all patients, the obstruction in aqueduct or outflow parts of the fourth ventricle was proved by MRI. During the surgery, V-P shunt was clipped and ETV was performed. In case of favourable clinical state and MRI functional stoma, the V-P shunt has been removed 3 months after ETV. These patients with V-P shunt possible removing were evaluated as successful. In our group of 42 patients we were successful in 29 patients (69%). There were two serious complications (4.7%)—one patient died 2.5 years and one patient died 1 year after surgery in consequence of delayed ETV failure. ETV is the method of choice in obstructive hydrocephalus even in patients with former V-P shunt implantation. In case of acute or scheduled V-P shunt surgical revision, MRI is feasible, and if ventricular system obstruction is diagnosed, the hydrocephalus may be solved endoscopically. PMID:23984061

Chlachula, Martin; Hrbac, Tomas; Lipina, Radim

2013-01-01

46

Endoscopic third ventriculostomy in previously shunted children.  

PubMed

Endoscopic third ventriculostomy (ETV) is a routine and safe procedure for therapy of obstructive hydrocephalus. The aim of our study is to evaluate ETV success rate in therapy of obstructive hydrocephalus in pediatric patients formerly treated by ventriculoperitoneal (V-P) shunt implantation. From 2001 till 2011, ETV was performed in 42 patients with former V-P drainage implantation. In all patients, the obstruction in aqueduct or outflow parts of the fourth ventricle was proved by MRI. During the surgery, V-P shunt was clipped and ETV was performed. In case of favourable clinical state and MRI functional stoma, the V-P shunt has been removed 3 months after ETV. These patients with V-P shunt possible removing were evaluated as successful. In our group of 42 patients we were successful in 29 patients (69%). There were two serious complications (4.7%)-one patient died 2.5 years and one patient died 1 year after surgery in consequence of delayed ETV failure. ETV is the method of choice in obstructive hydrocephalus even in patients with former V-P shunt implantation. In case of acute or scheduled V-P shunt surgical revision, MRI is feasible, and if ventricular system obstruction is diagnosed, the hydrocephalus may be solved endoscopically. PMID:23984061

Brichtova, Eva; Chlachula, Martin; Hrbac, Tomas; Lipina, Radim

2013-01-01

47

Reduction of ventricular size after shunting for normal pressure hydrocephalus related to CSF dynamics before shunting  

Microsoft Academic Search

Reduction of ventricular size was determined by repeated computed tomography in 30 adult patients shunted for normal pressure hydrocephalus (NPH) and related to the pressure-volume index (PVI) and resistance to outflow of cerebrospinal fluid (Rcsf) measured before shunting. Rapid and marked reduction of ventricular size (n = 10) was associated with a significantly lower PVI than slow and moderate to

J T Tans; D C Poortvliet

1988-01-01

48

Portocaval shunt for hepatocyte package  

PubMed Central

In developing therapeutic alternatives to liver transplantation, we have used the strategy of applying a small intestinal segment as a scaffold for hepatocyte transplantation and also as a portocaval shunt (PCS) system to address both liver dysfunction and portal hypertension. The aim of this study was to investigate the feasibility of such an intestinal segment in animal models. Hepatocytes isolated from luciferase-transgenic Lewis rats were transplanted into jejunal segments of wild-type Lewis rats with mucosa removal without PCS application. Luciferase-derived luminescence from transplanted hepatocytes was stably detected for 30 days. Then, we performed autologous hepatocyte transplantation into the submucosal layer of an isolated and vascularized small intestinal segment in pigs. Transplanted hepatocytes were isolated from the resected left-lateral lobe of the liver. On day 7, hepatocyte clusters and bile duct-like structures were observed histologically. To create an intestinal PCS system in pigs, an auto-graft of the segmental ileum and interposing vessel graft were anastomosed to the portal vein trunk and inferior vena cava. However, thrombi were observed in vessels of the intestinal PCSs. We measured the correlation between infusion pressure and flow volume in whole intestines ex vivo in both species and found that the high pressure corresponding to portal hypertension was still insufficient to maintain the patency of the intestinal grafts. In conclusion, we demonstrated the feasibility of the small intestine as a scaffold for hepatocyte transplantation in rat and pig models, but PCS using an intestinal graft failed to maintain patency in a pig model. PMID:23974217

Iwasaki, Junji; Hata, Toshiyuki; Uemoto, Shinji; Fujimoto, Yasuhiro; Kanazawa, Hiroyuki; Teratani, Takumi; Hishikawa, Shuji; Kobayashi, Eiji

2013-01-01

49

[Anesthesia in peritoneovenous shunt placement].  

PubMed

Since 1984 the peritoneovenous shunt has been installed in 33 patients because of resistant ascites. The aim of this study was to find the optimal type of anesthesia in our conditions on our own clinical-patient material. All patients were classified by the ASA, Goldman, Child and Child-Puigh score. The patient, surgeon and anesthesiologist were polled about the quality of anesthesia, and all observed complications were followed, like after different premedications as well as in the course and after different types of neuroleptic anesthesia. General neuroleptic anesthesia was applied in 23 patients (69.7%), one was operated on in ketamine anesthesia (3.0%) and 9 (27.3%) in local anesthesia with 2% Xylocaine. After premedication with Thalamonal in all patients there came to a fall in arterial pressure for more than 20% of initial values and the feeling of uneasiness and fear was present. All patients with local anesthesia absolutely needed additional application of sedation or analgesia, especially during the formation of the subcutaneous tunnel, and neither patient nor surgeon were satisfied with the achieved comfort. During the course of neuroleptic anesthesia with Thalamonal hypotension developed, in 17/20 patients an in 2/20 the presence of prolonged apnea demanded additional artificial ventilation. In the patient operated on in ketamine anesthesia, an acute psychotic reaction developed, followed by visual and acustic hallucinations without signs of metabolic encephalopathy. On the basis of our own experience, we conclude that general neuroleptic anesthesia with the use of Flormidal as an anesthetic and Fentanil as an analgetic, is the method of choice, and that local anesthesia can be recommended only on one operative site (except the subcutaneous tunnel). PMID:2098643

Gavrilovi?, S; Gvozdenovi?, L; Jerkovi?-Danici?, B; Pjevi?, M; Kovacevi?, S

1990-01-01

50

Decomposition Methods for Large Scale LP Decoding  

E-print Network

problems apparently dates only to Jon Feldman's 2003 Ph.D. thesis [13,15]. ... Variable update their estimates of the true variable assignment based on information ... enables us to write LP solvers with wall-clock speeds comparable to (and ...

2012-04-02

51

Observations Figure 1: Lunar Prospector (LP) magnetometer  

E-print Network

near 0.3 Hz. This emission is commonly seen by LP in the magnetosheath. Electromagnetic Wave Power, and plasma waves can create source signals. · The Moon encounters a wide variety plasma regimes and EM source with an increase in wave power. Note the narrowband increase in wave power near the end of the interval centered

Fillingim, Matthew

52

Radionuclide demonstration of intrapulmonary shunting in cirrhosis  

SciTech Connect

The association of hepatic cirrhosis and severe arterial hypoxemia has been well described. Although alterations in ventilatory function may partially account for the hypoxemia, the principal mechanism is thought to be a microangiopathic change in the pulmonary vasculature resulting in intrapulmonary arteriovenous shunting with resultant systemic desaturation. Whole-body radionuclide scans with technetium-99m macroaggregated albumin labeling have been diagnostic of right-to-left shunting by their demonstration of tracer accumulation within the extrapulmonary circulation. A case of severe pulmonary arteriovenous shunting in an alcoholic patient in whom hepatic disease had not been of apparent clinical significance before radionuclide scanning is reported. He did not have cuntaeous angiomata as have all other patients with alcoholic cirrhosis and hypoxemia.

Bank, E.R.; Thrall, J.H.; Dantzker, D.R.

1983-05-01

53

Radionuclide demonstration of intrapulmonary shunting in cirrhosis  

SciTech Connect

The association of hepatic cirrhosis and severe arterial hypoxemia has been well described. Although alterations in ventilatory function may partially account for the hypoxemia, the principal mechanism is thought to be a microangiopathic change in the pulmonary arteriovenous shunting with resultant systemic desaturation. Whole-body radionuclide scans with technetium-99m macroaggrregated albumin (/sup 99m/Tc MAA) labeling have been diagnostic of right-to-left shunting by their demonstration of tracer accumulation within the extrapulmonary circulation. A case of severe pulmonary arteriovenous shunting in an alcoholic patient in whom hepatic disease had not been of apparent clinical significance before radionuclide scanning is reported. He did not have cutaneous angiomata as have all other patients with alcoholic cirrhosis and hypoxemia.

Bank, E.R.; Thrall, J.H.; Dantzker, D.R.

1983-05-01

54

Congenital portosystemic shunts in dogs and cats.  

PubMed

Congenital portosystemic shunts (PPS) are abnormal vascular communications that allow blood from the intestine to bypass the liver, and are classified as intrahepatic or extrahepatic. Clinical signs are generally related to the nervous, gastrointestinal or urinary systems, and are often vague. In addition, changes present on routine blood analysis are often mild and non-specific. For this reason, alternative tests are required for a diagnosis. Diagnostic tests include serum bile-acid concentrations, ammonia tolerance test, portography, ultrasonography and/or scintigraphy. Medical therapy involves reducing absorption of encephalopathic toxins from the gastrointestinal tract and may prolong survival. Surgical therapy is aimed at attenuation of the shunting vessel and provides improved survival rates. The traditional approach has been complete or partial ligation of the shunt. More recent approaches have involved slow, progressive attenuation with ameroid constrictors or cellophane banding. Overall, prognosis following surgical therapy is good in dogs and fair in cats. PMID:15726125

Broome, C J; Walsh, V P; Braddock, J A

2004-08-01

55

Carbon shunting arc and its induced plasma  

NASA Astrophysics Data System (ADS)

A pulsed carbon arc is produced in a low-pressure gas or vacuum without any external trigger source. The arc is initiated around a carbon rod that is heated using a same power source with the arc. This is called a shunting arc and it is characteristic that the arc is self-initiated and its current of over 1000 A with a sinusoidal waveform is easily attained. Spectroscopic measurement shows that the shunting arc induces a new nitrogen plasma in the chamber. Thus, two different plasmas exist in one shunting arc production process. As a preliminary research of plasma-based ion implantation, pulsed carbon ions are extracted from the arc plasma and implanted into a target placed in the chamber by directly applying a pulsed high voltage to the target.

Yukimura, Ken; Yoshioka, Kenji; Tani, Yuji

2000-02-01

56

Arteriovenous shunt-circulation in lymphoedematous limbs.  

PubMed

In lymphoedema of the extremities arteriovenous shunt circulation develops. Regulation of limb circulation was studied in 28 cases of (primary and secondary) lymphoedema by using the venous isotope dilution method and technetium-macroaggregate perfusion scintigraphy. As a result of lymphoedema, limb circulation (total limb circulation) increases, arteriovenous O2 difference is low and the O2 uptake of the tissues is normal. The development of arteriovenous (micro-, and macro-) shunts can be directly visualized by perfusion scintigraphy. In lymphoedema of the extremities the nutritive--capillary--blood supply of the tissues remains normal and therefore, no trophic disturbances develop. Lymphoedema is often associated with a fairly considerable arteriovenous shunt circulation and, in such cases, the cardiac output as well as cardiac performance are enhanced. PMID:3591169

Solti, F; Iskum, M; Bános, C; Salamon, F

1986-01-01

57

The rabbit blood shunt subarachnoid haemorrhage model.  

PubMed

The recently introduced rabbit blood shunt subarachnoid haemorrhage model is based on the two standard procedures of subclavian artery cannulation and transcutaneous cisterna magna puncture. An extracorporeal shunt placed in between the arterial system and the subarachnoid space allows examiner-independent SAH in a closed cranium. Despite its straightforwardness, it is worth examining some specific features and characteristics of the model. We outline technical considerations to successfully perform the model with minimal mortality and morbidity. In addition, we discuss outcome measures, advantages and limitations, and the applicability of the model for the study of early brain injury and delayed cerebral vasospasm after SAH. PMID:25366648

Marbacher, Serge; Fathi, Ali Reza; Muroi, Carl; Coluccia, Daniel; Andereggen, Lukas; Neuschmelting, Volker; Widmer, Hans Rudolf; Jakob, Stephan M; Fandino, Javier

2015-01-01

58

75 FR 38514 - Application to Export Electric Energy; Brookfield Energy Marketing LP  

Federal Register 2010, 2011, 2012, 2013, 2014

...SUMMARY: Brookfield Energy Marketing LP (BEM LP) has applied for authority to transmit...2010, DOE received an application from BEM LP for authority to transmit electric energy...transmission facilities for five years. BEM LP does not own any electric...

2010-07-02

59

78 FR 45592 - DeltaPoint Capital IV, LP;  

Federal Register 2010, 2011, 2012, 2013, 2014

...SMALL BUSINESS ADMINISTRATION [License No. 02/02-0662] DeltaPoint Capital IV, LP; Notice Seeking...given that DeltaPoint Capital IV, L.P., 45 East...the Small Business Administration (``SBA'') Rules...730). DeltaPoint Capital IV, L.P....

2013-07-29

60

Recurrent Breast Cancer in a Patient with a Ventriculoperitoneal Shunt  

PubMed Central

We report a case of a patient with recurrent infiltrating ductal carcinoma of the breast encasing a ventriculoperitoneal shunt. We also review the current literature regarding reports of breast malignancy around a ventriculoperitoneal shunt, as well as the potential relevance of such shunts to the preoperative evaluation and management of patients with breast cancer.

Copeland-Halperin, Libby R.; Cohen, Robert A.

2015-01-01

61

Energy Storage Options for Hybrid Diesel Electric Shunting Locomotives  

Microsoft Academic Search

Shunting locomotives are required to produce high powers during shunting operations but may be idle for many hours each day. A key issue with a hybrid conversion is battery life. Shunting locomotives are required to develop typically 1000hp to 2000hp for periods of perhaps a few minutes and the battery is sized for its capacity to deliver instantaneous power. This

Peter Wolfs

62

Lipoprotein particles in homozygous familial hypercholesterolemic patients treated with portacaval shunt and LDL apheresis.  

PubMed

Lipoprotein particles containing apolipoproteins (Apo) were studied by enzyme-linked-immunosorbent assay in two homozygous familial hypercholesterolemic patients (1 male and 1 female) with portacaval shunts, and in controls. Total Apo B, total cholesterol and LDL cholesterol were increased in both patients while complex Apo B containing particles, Lp CIII: B, were not increased in these FH patients. The dextran-sulfate cellulose columns (Liposorber LA-40) had an excellent adsorption selectivity and adsorption capacity for lipoprotein particles containing Apo B and a minimum adsorption capacity in Apo AI and Apo AII-containing particles. This apheresis technique selectively depleted plasma of atherogenic Apo B-containing particles with a minimal loss of antiatherogenic Apo AI-containing particles. PMID:2282694

Gairin, D; Monard, F; Cachera, C; Bard, J M; Amouyel, P; Duriez, P; Tacquet, A; Fruchart, J C

1990-12-14

63

77 FR 58366 - Dominion South Pipeline Company, L.P.; Gulf Shore Energy Partners, LP; Notice of Applications  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket...Company, L.P.; Gulf Shore Energy Partners, LP; Notice of Applications...abandon by sale to Gulf Shore Energy Partners, LP (Gulf Shore...South and to install certain compression facilities. Gulf Shore...

2012-09-20

64

The Delta Valve: a physiologic shunt system  

Microsoft Academic Search

PS Medical has advanced the state-of-the-art in hydrocephalus valve technology with the introduction of the Delta Valve. The Delta Valve is designed upon the premise that the shunted patient should have intracranial pressure (ICP) maintenance within a normal range regardless of cerebrospinal fluid (CSF) flow rate or body position. All previous valves have performance characteristics that are greatly influenced by

David A. Watson

1994-01-01

65

Optimal shunt compensators at nonsinusoidal busbars  

Microsoft Academic Search

A model for determining an optimal shunt capacitor value at nonsinusoidal busbars combining three basic criteria maximizing the power factor, minimizing the line losses, and maximizing the transmission efficiency is developed. The choice of the capacitor value is constrained by the values that may cause resonance. This model was solved employing the penalty function approach and the golden Section Search

I. M. El-Amin; S. O. Duffuaa; A. U. Bawah

1995-01-01

66

Design and Application of EHV Shunt Reactors  

Microsoft Academic Search

This paper discusses the use of EHV shunt reactors on transmission systems from the application and reactor design viewpoints. Various factors relating to reactor construction, including testing, are discussed, and emphasis is placed on a gapped-core design for EHV applications. The results of steady-state and transient performance studies for this design are presented.

G. W. Alexander; R. H. Hopkinson; A. U. Welch

1966-01-01

67

Cerebrospinal fluid shunt infections in infants.  

PubMed

Infection remains a major cause of morbidity and mortality following CSF shunt procedures. In this study 191 shunt procedures carried out from January 1981 to December 1992 in a series of 81 infants (less than 6 months old) were retrospectively analyzed for possible risk factors. The overall surgical infection rate was 7.8%, with 15 infections occurring in 14 patients (17.2%). No significant difference in the rate of infections was found in relation to sex, birth weight, gestational age, and type of shunt procedure (primary insertion/revision). The occurrence of other infections during the period of shunt surgery did not influence the infection risk either. Intraventricular hemorrhage and central nervous system infections as causes of the hydrocephalus were found to correlate with septic risk. Young age (less than 6 months) seems to represent the main risk factor, and this is related both to the immunologic deficiency and to the particular features of residential bacterial flora in this age group. PMID:8608581

Dallacasa, P; Dappozzo, A; Galassi, E; Sandri, F; Cocchi, G; Masi, M

1995-11-01

68

Automatic Voltage Regulation of DC Shunt Generators  

Microsoft Academic Search

In a dc shunt generator, as the load increases the terminal voltage falls, giving a drooping characteristic. The regulation of voltage involves the adjustment of field excitation. A simple method of voltage regulation by automatic adjustment of field excitation making use of transistor circuitry is discussed. The added advantage of this method is that by the simple adjustment of circuit

Vimal Singh; S. K. Kak; Srinivasan Rangarajan

1973-01-01

69

POWER HARVESTING PIEZOELECTRIC SHUNT DAMPING 1  

E-print Network

POWER HARVESTING PIEZOELECTRIC SHUNT DAMPING 1 A. J. Fleming ¤ S. O. R. Moheimani ¤ ¤ School of harvesting the real power normally dissipated by resistive network elements. Keywords: Dampers, Passive, the passive network combined with the inherent capacitance of the PZT creates a damped electrical resonance

Fleming, Andrew J.

70

The clinical anatomy of congenital portosystemic venous shunts.  

PubMed

Congenital portosystemic venous shunts are rare. Their gross anatomy has not been well defined. Four different varieties of congenital portosystemic venous shunts are described in six children seen during a 10-year period, focusing on the anatomy of the shunt as determined by imaging studies and surgery. A detailed review of the literature indicates that congenital portosystemic venous shunts are best classified as: extrahepatic or intrahepatic. Extrahepatic shunts may be further subdivided into portocaval shunts (type 1 end-to-side and type 2 side-to-side) and others. Intrahepatic shunts are due to an abnormal intrahepatic connection between the portal vein and hepatic vein/inferior vena cava or a persistent patent ductus venosus. Additional congenital anomalies, particularly cardiac malformations, may be associated with any type. Some congenital intrahepatic portosystemic venous shunts close spontaneously in infancy; all other congenital portosystemic venous shunts tend to remain patent. To a variable extent, depending largely on the volume and duration of the shunt, affected individuals are at risk of developing hepatic encephalopathy and/or an intrahepatic tumor. The key to understanding the pathogenesis of these shunts lies in the normal developmental mechanisms underlying the formation of the portal vein and inferior vena cava in the embryo. PMID:18161055

Stringer, Mark D

2008-03-01

71

Passively Shunted Piezoelectric Damping of Centrifugally-Loaded Plates  

NASA Technical Reports Server (NTRS)

Researchers at NASA Glenn Research Center have been investigating shunted piezoelectric circuits as potential damping treatments for turbomachinery rotor blades. This effort seeks to determine the effects of centrifugal loading on passively-shunted piezoelectric - damped plates. Passive shunt circuit parameters are optimized for the plate's third bending mode. Tests are performed both non-spinning and in the Dynamic Spin Facility to verify the analysis, and to determine the effectiveness of the damping under centrifugal loading. Results show that a resistive shunt circuit will reduce resonant vibration for this configuration. However, a tuned shunt circuit will be required to achieve the desired damping level. The analysis and testing address several issues with passive shunt circuit implementation in a rotating system, including piezoelectric material integrity under centrifugal loading, shunt circuit implementation, and tip mode damping.

Duffy, Kirsten P.; Provenza, Andrew J.; Trudell, Jeffrey J.; Min, James B.

2009-01-01

72

Surgical treatment of intrahepatic portosystemic shunts in 45 dogs.  

PubMed

The surgical attenuation of an intrahepatic portosystemic shunt in 45 dogs is described. Twenty-nine (64 per cent) had left divisional shunts consistent with a patent ductus venosus (PDV), 15 (33 per cent) had central divisional shunts and one had a right divisional shunt. In the dogs with a PDV, the shunt vessel could be most easily manipulated at a posthepatic site, whereas in those with central and right divisional shunts the manipulation could be more easily made intrahepatically but sometimes involved demanding intravascular surgical techniques. Eight dogs (18 per cent) died during the surgery or shortly afterwards. Of the 37 dogs surviving longer term, 28 (76 per cent) became clinically normal and required no medication or diet control. In a further three animals the shunt was ligated completely only during a second surgical procedure. The remaining six dogs were euthanased because of clinical signs of encephalopathy which were either surgically or medically uncontrollable. PMID:9587198

White, R N; Burton, C A; McEvoy, F J

1998-04-01

73

Congenital portosystemic shunts in toy and miniature poodles.  

PubMed

Three male Poodles (two Toy, one Miniature) were presented to their veterinarians for evaluation of urolithiasis and varying degrees of hepatic encephalopathy. All three dogs were diagnosed as having intrahepatic shunts and referred for surgical correction. In each case, shunts arose from the right branch of the portal vein and were amenable to perivascular dissection caudal to where the vessel entered the hepatic parenchyma and to placement of perivascular cellophane bands to achieve shunt attenuation. During the same period, a female Miniature Poodle also presented for treatment of a congenital portosystemic shunt discovered during evaluation for generalised motor seizures. This animal had an extrahepatic portoazygous shunt that was completely ligated. Congenital portosystemic shunts have not previously been identified in Toy and Miniature Poodles at the University Veterinary Centre, Sydney and the anatomical types of shunt seen in this breed have not previously been reported in a consecutive series of cases. The three male dogs are noteworthy for a number of reasons: all had intrahepatic shunts, despite being small breed dogs; all three presented in a similar fashion, and all had shunts of an anatomical type amenable to placement of cellophane bands. One male dog died within 12 hours of surgery, the remaining three dogs survived and their liver function was normal at follow-up between 2 and 3 months after surgery. Use of cellophane bands for successful attenuation of intrahepatic shunts has not been previously reported. PMID:10979507

Hunt, G B; Tisdall, P L; Webb, A; MacPherson, G C; Brain, P; Malik, R

2000-08-01

74

Incidence and risk factors of ventriculoperitoneal shunt infections in children: a study of 333 consecutive shunts in 6 years.  

PubMed

The major aims of this study were to estimate the infection rate and recognize the risk factor for ventriculoperitoneal (VP) shunt infections in children. To analyze shunt infection rate and identify risk factors, a retrospective cohort analysis of 333 consecutive VP shunt series was performed at Seoul National University Children's Hospital in Korea between January 2005 and February 2011. Overall, 35 shunts (10.5%) were infected, which represented an infection rate of 0.075 infection cases per shunt per year. VP shunt infection occurred at a median of 1 month (range, 6 days to 8 months) after insertion. An independent risk factor for shunt infection was undergoing an operation before the first year of life (relative risk 2.31; 95% confidence interval, 1.19-4.48). The most common causative microorganism was coagulase-negative staphylococci in 16 (45.7%) followed by Staphylococcus aureus in 8 (22.9%). Methicillin resistance rate was 83.3% among coagulase-negative staphylococci and S. aureus. In this study, cerebrospinal fluid shunt infection rate was 10.5%. Infection was frequently caused by methicillin-resistant coagulase-negative staphylococci and S. aureus within two months after shunt surgery. Vancomycin may be considered as the preoperative prophylaxis for shunt surgery in a situation where methicillin resistance rate is very high. PMID:23255859

Lee, Joon Kee; Seok, Joon Young; Lee, Joon Ho; Choi, Eun Hwa; Phi, Ji Hoon; Kim, Seung-Ki; Wang, Kyu-Chang; Lee, Hoan Jong

2012-12-01

75

Incidence and Risk Factors of Ventriculoperitoneal Shunt Infections in Children: A Study of 333 Consecutive Shunts in 6 Years  

PubMed Central

The major aims of this study were to estimate the infection rate and recognize the risk factor for ventriculoperitoneal (VP) shunt infections in children. To analyze shunt infection rate and identify risk factors, a retrospective cohort analysis of 333 consecutive VP shunt series was performed at Seoul National University Children's Hospital in Korea between January 2005 and February 2011. Overall, 35 shunts (10.5%) were infected, which represented an infection rate of 0.075 infection cases per shunt per year. VP shunt infection occurred at a median of 1 month (range, 6 days to 8 months) after insertion. An independent risk factor for shunt infection was undergoing an operation before the first year of life (relative risk 2.31; 95% confidence interval, 1.19-4.48). The most common causative microorganism was coagulase-negative staphylococci in 16 (45.7%) followed by Staphylococcus aureus in 8 (22.9%). Methicillin resistance rate was 83.3% among coagulase-negative staphylococci and S. aureus. In this study, cerebrospinal fluid shunt infection rate was 10.5%. Infection was frequently caused by methicillin-resistant coagulase-negative staphylococci and S. aureus within two months after shunt surgery. Vancomycin may be considered as the preoperative prophylaxis for shunt surgery in a situation where methicillin resistance rate is very high. PMID:23255859

Lee, Joon Kee; Seok, Joon Young; Lee, Joon Ho; Phi, Ji Hoon; Kim, Seung-Ki; Wang, Kyu-Chang; Lee, Hoan Jong

2012-01-01

76

Scientific heritage of L.P. Shilnikov  

NASA Astrophysics Data System (ADS)

This is the first part of a review of the scientific works of L.P. Shilnikov. We group his papers according to 7 major research topics: bifurcations of homoclinic loops; the loop of a saddle-focus and spiral chaos; Poincare homoclinics to periodic orbits and invariant tori, homoclinic in noautonous and infinite-dimensional systems; Homoclinic tangency; Saddlenode bifurcation — quasiperiodicity-to-chaos transition, blue-sky catastrophe; Lorenz attractor; Hamiltonian dynamics. The first two topics are covered in this part. The review will be continued in the further issues of the journal.

Afraimovich, Valentin S.; Gonchenko, Sergey V.; Lerman, Lev M.; Shilnikov, Andrey L.; Turaev, Dmitry V.

2014-07-01

77

Peritoneovenous shunt occlusion. Etiology, diagnosis, therapy.  

PubMed Central

Electronic pressure testing of every LeVeen valve has practically eliminated mechanical malfunction as a cause of shunt failure. Nonetheless, failures do occur and in a series of 240 cases, early or late shunt failure occurred in 29 patients. Thirty-five additional cases of failures were either referred by other physicians over a period of 6 years or information and x-rays were accumulated by direct contact. Shunt failure becomes manifest by a sudden reaccumulation of ascites in patients with a previously functioning shunt. In immediate failure, the ascites may fail to disappear after surgery or reaccumulate if removed. Ideally, caval clotting should be first excluded by x-ray visualization of the superior vena prior to injection of the shunt with contrast agent. Shuntograms are done with fine-bore needles. The venous pressure is also measured. The entry of contrast into the vena cava without pooling indicates a patent venous limb. The contrast will empty from the venous tubing with forceful inspiration if the entire system is patent. The venous tube will not clear if the valve or peritoneal collecting tubes are blocked. Only the valve and collecting tube need then be replaced if contrast enters the cava but does not leave the venous tubing. Occluded valves must not be flushed to restore patency since inflammatory exudate and cellular debris are erroneously identified as "fibrin flecks." Histology and culture are mandatory. Immediate and early failure are often caused by malposition of the venous tubing. Malplacements can often be diagnosed simply by chest x-rays. Intraoperative injection of methylene blue into the venous tubing establishes a satisfactory washout prior to wound closure. Fresh clots in the vena cava can be dissolved by the slow injection of streptokinase into the venous tubing. Other patent veins are chosen for access. Patients having repeat surgery after clotting must be heparinized to prevent a similar recurrence. Flushing blood clots from the cava can be fatal. Images FIG. 1. FIG. 2. FIGS. 3A and B. FIG. 4. FIG. 5. FIG. 6. FIG. 7. FIG. 8. FIG. 10. FIG. 11. FIG. 12. FIG. 13. FIGS. 14A and B. FIG. 15. FIG. 16. FIG. 17. FIG. 18. FIGS. 19A and B. FIGS. 20A and B. PMID:6465977

LeVeen, H H; Vujic, I; d'Ovidio, N G; Hutto, R B

1984-01-01

78

Delayed incidental diagnosis of postoperative extradural hematoma following ventriculoperitoneal shunt  

PubMed Central

Ventriculo peritoneal (VP) shunt uncommonly complicates as intracranial hematomas which can still occur in patients with a functioning VP shunt leading to a delay in the diagnosis which can be extremely dangerous and lead to adverse outcomes. We report a case of an incidental diagnosis of delayed post-operative EDH following VP shunt in an young adult patient with a right cerebellar lesion and highlight the need for meticulous post-operative neurological examination. PMID:25552861

Byrappa, Vinay; Redhu, Shruti; Varadarajan, Bhadrinarayan

2015-01-01

79

Large area shunt defect free GaAs solar cells  

Microsoft Academic Search

Shunt defects have been found to be the type of defect that can degrade and cause failure in GaAs solar cells. Because of their catastrophic effects, it is necessary to ensure that no shunt defects are formed in the solar cell. A technique for fabricating large-area shunt-defect-free GaAs solar cells has been investigated. A Be-doped GaAlAs window layer was grown

Louis C. Kilmer; Allen M. Barnett

1990-01-01

80

Rescue endoscopic third ventriculostomy for repeated shunt blockage  

PubMed Central

The role of endoscopic third ventriculostomy (ETV) is getting more popular for all types of hydrocephalus. It has several advantages and is also being considered for malfunctioning of ventriculo-peritoneal shunt. A 16-year-old child had fourteen shunt revisions in his life. He was eventually treated with ETV with successful result. Repeated shunt failure can be an additional indication of ETV. PMID:21977099

Goyal, Puneet K.; Meher, Sujit K.; Singh, Daljit; Singh, Hukum; Tandon, Monica

2011-01-01

81

Rescue endoscopic third ventriculostomy for repeated shunt blockage.  

PubMed

The role of endoscopic third ventriculostomy (ETV) is getting more popular for all types of hydrocephalus. It has several advantages and is also being considered for malfunctioning of ventriculo-peritoneal shunt. A 16-year-old child had fourteen shunt revisions in his life. He was eventually treated with ETV with successful result. Repeated shunt failure can be an additional indication of ETV. PMID:21977099

Goyal, Puneet K; Meher, Sujit K; Singh, Daljit; Singh, Hukum; Tandon, Monica

2011-01-01

82

Semi-shunt field emission in electronic devices  

NASA Astrophysics Data System (ADS)

We introduce a concept of semi-shunts representing needle shaped metallic protrusions shorter than the distance between a device electrodes. Due to the lightening rod type of field enhancement, they induce strong electron emission. We consider the corresponding signature effects in photovoltaic applications; they are: low open circuit voltages and exponentially strong random device leakiness. Comparing the proposed theory with our data for CdTe based solar cells, we conclude that stress can stimulate semi-shunts' growth making them shunting failure precursors. In the meantime, controllable semi-shunts can play a positive role mitigating the back field effects in photovoltaics.

Karpov, V. G.; Shvydka, Diana

2014-08-01

83

Intracranial calcified pseudocyst reaction to a shunt catheter.  

PubMed

A 9-year-old boy with spina bifida, Chiari II malformation, and hydrocephalus presented with signs of increased intracranial pressure consistent with a shunt malfunction. Radiological investigations revealed an intracranial calcified lesion along the ventricular catheter. A shunt tap revealed a translucent milky white fluid. The patient underwent a ventriculostomy and, eventually, a shunt revision. Pathology findings were consistent with the formation of dystrophic calcification and a pseudocyst around the shunt catheter. Postoperatively, the patient returned to his neurological baseline. This is, to the best of the authors' knowledge, the first report of an intracranial calcified pseudocyst in a patient with normal renal function. PMID:24329159

Yowtak, June; Hughes, Douglas; Heger, Ian; Macomson, Samuel D

2014-02-01

84

Huge Thrombosis as a Consequence of VA-Shunts  

Microsoft Academic Search

\\u000a \\u000a Objective  Thrombosis is a rare but serious consequence of VA-shunts. We present two cases of near fatal thrombosis and its successful\\u000a (but in case 2, atypical) management.\\u000a \\u000a \\u000a \\u000a \\u000a Results  Case 1: A 38-year-old woman with VA-shunt suffered from rapidly progressing heart failure and later from progressing underdrainage\\u000a signs nine years after shunting due to a thrombus on the atrial shunt catheter that occluded

Michael Kiefer; Regina Eymann

85

Superconducting fault current-limiter with variable shunt impedance  

DOEpatents

A superconducting fault current-limiter is provided, including a superconducting element configured to resistively or inductively limit a fault current, and one or more variable-impedance shunts electrically coupled in parallel with the superconducting element. The variable-impedance shunt(s) is configured to present a first impedance during a superconducting state of the superconducting element and a second impedance during a normal resistive state of the superconducting element. The superconducting element transitions from the superconducting state to the normal resistive state responsive to the fault current, and responsive thereto, the variable-impedance shunt(s) transitions from the first to the second impedance. The second impedance of the variable-impedance shunt(s) is a lower impedance than the first impedance, which facilitates current flow through the variable-impedance shunt(s) during a recovery transition of the superconducting element from the normal resistive state to the superconducting state, and thus, facilitates recovery of the superconducting element under load.

Llambes, Juan Carlos H; Xiong, Xuming

2013-11-19

86

Spontaneous Portoazygos Shunt in a Patient with Portal Hypertension  

PubMed Central

We present a case of spontaneous portoazygos shunt in a patient with liver cirrhosis and portal hypertension. The shunt was incidentally detected by abdominal magnetic resonance imaging for routine evaluation of liver cirrhosis. Multiplanar reconstruction images demonstrated the portal vein communicating with the azygos vein that was dilated and tortuous along its course to the mediastinum. Although there has been a case of congenital portoazygos shunt reported in a neonate with multiple congenital anomalies, to the best of our knowledge, this is the first case of spontaneous portoazygos shunt developed in an adult with portal hypertension. PMID:24421946

Gebrael, Jacob; Yu, Hyeon; Hyslop, William Brian

2013-01-01

87

Lithium in LP 944-20  

E-print Network

We present a new estimate of the lithium abundance in the atmosphere of the brown dwarf LP 944-20. Our analysis is based on a self-consistent analysis of low, intermediate and high resolution optical and near-infrared spectra. We obtain log N(Li) = 3.25 +/-0.25 using fits of our synthetic spectra to the Li I resonance line doublet profiles observed with VLT/UVES and AAT/SPIRAL. This lithium abundance is over two orders of magnitude larger than previous estimates in the literature. In order to obtain good fits of the resonance lines of K I and Rb I and better fits to the TiO molecular absorption around the Li I resonance line, we invoke a semi-empirical model atmosphere with the dusty clouds located above the photosphere. The lithium abundance, however, is not changed by the effects of the dusty clouds. We discuss the implications of our estimate of the lithium abundance in LP 944-20 for the understanding of the properties of this benchmark brown dwarf.

Ya. V. Pavlenko; H. R. A. Jones; E. L. Martin; E. Guenther; M. A. Kenworthy; M. R. Zapatero Osorio

2007-07-14

88

Does the shunt opening pressure influence the effect of shunt surgery in normal pressure hydrocephalus?  

Microsoft Academic Search

Summary Thirteen patients with normal pressure hydrocephalus were operated upon with an externally manoeuvrable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and

A. Larsson; Ch. Jensen; M. Bilting; S. Ekholm; H. Stephensen; C. Wikkelsö

1992-01-01

89

Placement of Gastrostomy Tubes in Patients with Ventriculoperitoneal Shunts Does Not Result in Increased Incidence of Shunt Infection or Decreased Survival  

Microsoft Academic Search

The objective of this study was to examine if G-tube (G-tube) placement in patients with ventriculoperitoneal (VP) shunts\\u000a results in shunt infection or impacts patient survival. We performed a retrospective cohort study. Patients underwent VP shunt\\u000a and G-tube placement. Incidence of shunt infection and patient survival were calculated. Fifty-five patients qualified for\\u000a the study. Shunt infection occurred in seven patients

Brent E. Roeder; Adnan Said; Mark Reichelderfer; Deepak V. Gopal

2007-01-01

90

76 FR 50881 - Airworthiness Directives; M7 Aerospace LP Airplanes  

Federal Register 2010, 2011, 2012, 2013, 2014

...2120-AA64 Airworthiness Directives; M7 Aerospace LP Airplanes AGENCY: Federal Aviation...airworthiness directive (AD) for certain M7 Aerospace LP Models SA226-T, SA226-T(B...information identified in this AD, contact M7 Aerospace, LC, 10823 NE. Entrance Road,...

2011-08-17

91

76 FR 68745 - Seneca Power Partners, L.P.  

Federal Register 2010, 2011, 2012, 2013, 2014

...Energy Regulatory Commission [Docket No. EL12-6-000] Seneca Power Partners, L.P. v. New York Independent System Operator...Commission) Rules of Practice and Procedures, 18 CFR 385.206, Seneca Power Partners, L.P. (Complainant) filed a complaint...

2011-11-07

92

Titel des Moduls: LP (nach ECTS): Kurzbezeichnung: Project Numerical Analysis  

E-print Network

Titel des Moduls: LP (nach ECTS): Kurzbezeichnung: Project Numerical Analysis 6 PNA Verantwortlich. Qualifikationsziele This is an advanced project course in Numerical Analysis. Students shall learn how to apply-Art SWS LP P / W / WP Semester Project Numerical Analysis IV 4 6 P WS/SS 5. Beschreibung der Lehrformen

Nabben, Reinhard

93

A Gravitational Interior Point Method for LP Katta G. Murty  

E-print Network

A Gravitational Interior Point Method for LP Katta G. Murty Department of Industrial and Operations-mail:katta murty@umich.edu October 2003 Abstract In [4, 1] gravitational methods for linear programming (LP) have a gravitational method of type (c) that behaves like an interior point method. To guarantee that the ball used has

Murty, Katta G.

94

76 FR 70040 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held...directive (AD) for certain Gulfstream Aerospace LP (type certificate previously held...Gulfstream G150 airplanes; and Gulfstream Aerospace LP Model Gulfstream 200 airplanes....

2011-11-10

95

75 FR 70939 - Approval of Saybolt LP, as a Commercial Gauger  

Federal Register 2010, 2011, 2012, 2013, 2014

...Approval of Saybolt LP, as a Commercial Gauger AGENCY: U.S. Customs...approval of Saybolt LP, as a commercial gauger...Saybolt LP, 7308 North Main Street, Jacksonville, FL 32208...scientific--svcs/commercial--gaugers/. DATES:...

2010-11-19

96

78 FR 53487 - Equinox Funds Trust and Equinox Institutional Asset Management LP; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...Trust and Equinox Institutional Asset Management LP; Notice of Application August...and Equinox Institutional Asset Management LP (the ``Initial Adviser...Liu, Equinox Institutional Asset Management LP, 47 Hulfish Street,...

2013-08-29

97

L^p Bernstein Inequalities and Radial Basis Function Approximation  

E-print Network

) by jf jW (Lp(Rd);T ) = jjTf jjp jjf jjW (Lp(Rd);T ) = jjf jjp + jf jW (Lp(Rd);T ) : The completion of C1c (R d), with respect to the above norm, will be denoted by W (Lp(Rd); T ). 8 1.4 Some Results for Lp Spaces We de ne the convolution of two...(R d), and for any f 2 Ckc (R d) we have f = Z Rd Tf(t) ( t)dt: (3.1) Now, given an f 2 Ckc (R d), we can form an approximant by replacing with a suitable kernel in (3.1). Since we are interested in approximating f by SX( ), the kernel...

Ward, John P.

2012-10-19

98

Shunting branch of portal vein and stent position predict survival after transjugular intrahepatic portosystemic shunt  

PubMed Central

AIM: To evaluate the effect of the shunting branch of the portal vein (PV) (left or right) and the initial stent position (optimal or suboptimal) of a transjugular intrahepatic portosystemic shunt (TIPS). METHODS: We retrospectively reviewed 307 consecutive cirrhotic patients who underwent TIPS placement for variceal bleeding from March 2001 to July 2010 at our center. The left PV was used in 221 patients and the right PV in the remaining 86 patients. And, 224 and 83 patients have optimal stent position and sub-optimal stent positions, respectively. The patients were followed until October 2011 or their death. Hepatic encephalopathy, shunt dysfunction, and survival were evaluated as outcomes. The difference between the groups was compared by Kaplan-Meier analysis. A Cox regression model was employed to evaluate the predictors. RESULTS: Among the patients who underwent TIPS to the left PV, the risk of hepatic encephalopathy (P = 0.002) and mortality were lower (P < 0.001) compared to those to the right PV. Patients who underwent TIPS with optimal initial stent position had a higher primary patency (P < 0.001) and better survival (P = 0.006) than those with suboptimal initial stent position. The shunting branch of the portal vein and the initial stent position were independent predictors of hepatic encephalopathy and shunt dysfunction after TIPS, respectively. And, both were independent predictors of survival. CONCLUSION: TIPS placed to the left portal vein with optimal stent position may reduce the risk of hepatic encephalopathy and improve the primary patency rates, thereby prolonging survival. PMID:24574750

Bai, Ming; He, Chuang-Ye; Qi, Xing-Shun; Yin, Zhan-Xin; Wang, Jian-Hong; Guo, Wen-Gang; Niu, Jing; Xia, Jie-Lai; Zhang, Zhuo-Li; Larson, Andrew C; Wu, Kai-Chun; Fan, Dai-Ming; Han, Guo-Hong

2014-01-01

99

LP based approach to optimal stable matchings  

SciTech Connect

We study the classical stable marriage and stable roommates problems using a polyhedral approach. We propose a new LP formulation for the stable roommates problem. This formulation is non-empty if and only if the underlying roommates problem has a stable matching. Furthermore, for certain special weight functions on the edges, we construct a 2-approximation algorithm for the optimal stable roommates problem. Our technique uses a crucial geometry of the fractional solutions in this formulation. For the stable marriage problem, we show that a related geometry allows us to express any fractional solution in the stable marriage polytope as convex combination of stable marriage solutions. This leads to a genuinely simple proof of the integrality of the stable marriage polytope. Based on these ideas, we devise a heuristic to solve the optimal stable roommates problem. The heuristic combines the power of rounding and cutting-plane methods. We present some computational results based on preliminary implementations of this heuristic.

Teo, Chung-Piaw [National Univ. of Singapore (Singapore); Sethuraman, J.

1997-06-01

100

Lithium in LP944-20  

NASA Astrophysics Data System (ADS)

We present a new estimate of the lithium abundance in the atmosphere of the brown dwarf LP944-20. Our analysis is based on a self-consistent analysis of low-, intermediate- and high-resolution optical and near-infrared spectra. We obtain logN(Li) = 3.25 +/- 0.25 using fits of our synthetic spectra to the LiI resonance line doublet profiles observed with Very Large Telescope/Ultraviolet-Visual Echelle Spectrograph (VLT/UVES) and Anglo-Australian Telescope/Segmented Pupil/Image Reformatting Array of Lenslets (AAT/SPIRAL). This lithium abundance is over two orders of magnitude larger than previous estimates in the literature. In order to obtain good fits of the resonance lines of KI and RbI and better fits to the TiO molecular absorption around the LiI resonance line, we invoke a semi-empirical model atmosphere with the dusty clouds located above the photosphere. The lithium abundance, however, is not changed by the effects of the dusty clouds. We discuss the implications of our estimate of the lithium abundance in LP944-20 for the understanding of the properties of this benchmark brown dwarf. Based on observations obtained on the European Southern Observatory at Cerro Paranal, Chile, in programs 68.C-0063(A) and 072.C-0110(B), the Anglo-Australian Telescope at Siding Springs Observatory during commissioning observations for SPIRAL (Segmented Pupil/Image Reformatting Array of Lenslets) instrument and the Keck Observatory in Mauna Kea, Hawaii. E-mail: yp@mao.kiev.ua

Pavlenko, Ya. V.; Jones, H. R. A.; Martín, E. L.; Guenther, E.; Kenworthy, M. A.; Zapatero Osorio, M. R.

2007-09-01

101

Development of Pulmonary Hypertension in Adults after Ventriculoatrial Shunt Implantation  

Microsoft Academic Search

Background: The insertion of ventriculoatrial (VA) shunts for the treatment of hydrocephalus is thought to be associated with the development of pulmonary hypertension in adults. Objectives: It was the aim of this study to describe the frequency and the clinical spectrum of pulmonary hypertension in adults with VA shunts. Methods: Patients with pulmonary hypertension were retrospectively evaluated from January 1999

Stefan Kluge; Hans Jörg Baumann; Jan Regelsberger; Uwe Kehler; Barbara Koziej; Hans Klose; Ulf Greinert; Georg Kreymann; Andreas Meyer

2009-01-01

102

Congenital intrahepatic portohepatic venous shunt: treatment with coil embolisation.  

PubMed

Congenital abnormalities of the portal venous system are rare. There are few radiological descriptions of intrahepatic portosystemic venous shunt detected in the perinatal period. We report a congenital portosystemic shunt that was detected by US and treated with coil embolisation in the neonatal period. PMID:10836599

Kim, I O; Cheon, J E; Kim, W S; Chung, J W; Yeon, K M; Yoo, S J; Seo, J K; Choi, J H

2000-05-01

103

Congenital intrahepatic portosystemic shunt with variant inferior right hepatic vein.  

PubMed

We present a case of congenital intrahepatic aneurysmal portosystemic shunt in which the right portal vein communicates with both a variant inferior right hepatic vein and the right hepatic vein. We also describe the importance and efficacy of three dimensional computed tomography reconstruction images in determining subtle, small shunt vessels. PMID:18553284

Senocak, Efsun; O?uz, Berna; Edgüer, Tahsin; Cila, Ay?enur

2008-06-01

104

Pulmonary hypertension as a result of asymptomatic portosystemic shunt.  

PubMed

This report describes a patient with severe pulmonary hypertension accompanied by a congenital intrahepatic portosystemic shunt. Primary pulmonary hypertension was suspected initially because none of the classic symptoms of a portosystemic shunt were present. Physicians should note that disorders of the portal system may cause pulmonary hypertension even in the absence of symptoms suggesting liver disease. PMID:10875741

Imamura, H; Momose, T; Kitabayashi, H; Takahashi, W; Yazaki, Y; Takenaka, H; Isobe, M; Sekiguchi, M; Kubo, K

2000-06-01

105

Congenital intrahepatic portosystemic shunt--an incidental rare anomaly.  

PubMed

Congenital intrahepatic shunts are rare anomalies that are usually incidental in a child who undergoes an ultrasound examination for some other reasons. Early diagnosis is important, because the condition can lead to hepatic encephalopathy and hypoglycemia. Author's would like to describe the findings of one such patient diagnosed to be having congenital intrahepatic shunt and discuss the clinical importance of this condition. PMID:17202645

Singh, Kunwarpal; Kapoor, Aprajita; Kapoor, Atul; Gupta, Kamini; Mahajan, Goldaa

2006-12-01

106

77 FR 53885 - Jordan Cove Energy Project LP, Pacific Connector Gas Pipeline LP; Notice of Extension of Comment...  

Federal Register 2010, 2011, 2012, 2013, 2014

...PF12-7-000; Docket No. PF12-17-000] Jordan Cove Energy Project LP, Pacific Connector...Additional Public Scoping Meetings for the Jordan Cove Liquefaction and Pacific Connector...scoping process and comment period for Jordan Cove Energy Project LP's (Jordan...

2012-09-04

107

77 FR 59393 - Jordan Cove Energy Project LP; Pacific Connector Gas Pipeline LP; Notice of Additional Public...  

Federal Register 2010, 2011, 2012, 2013, 2014

...PF12-7-000; Docket No. PF12-17-000] Jordan Cove Energy Project LP; Pacific Connector...Additional Public Scoping Meetings for the Jordan Cove Liquefaction and Pacific Connector...public scoping meetings to take comments on Jordan Cove Energy Project LP's (Jordan...

2012-09-27

108

Peritoneovenous shunt and neoplastic ascites: a 5-year experience report.  

PubMed

The cases of 42 patients with malignant ascites treated with a peritoneal venous shunt over a 5-year period are reviewed to establish the incidence of surgical and postsurgical complications. Although the yield of malignant cells found in the peripheral blood was increased after shunting, no new hematogenous metastases were observed after the operation. No evidence of disseminated intravascular coagulation was observed after shunt placement. While the shunt effectively relieved the discomfort due to abdominal distention and respiratory impairment, no restoration of cutaneous hypersensitivity was observed in the nine patients who were anergic prior to surgery. The median survival of patients with breast and gynecological cancer, after surgery, was significantly longer than the survival of patients with primary gastrointestinal neoplasma. In conclusion, peritoneal venous shunt appears to be an effective and safe method to improve the quality of life of patients with malignant ascites. PMID:3762170

Campioni, N; Pasquali Lasagni, R; Vitucci, C; Filippetti, M; Spagnoli, A; Pompei, S; Romano, P; Pasqualetti, A; Sorvillo, G; Sega, F M

1986-09-01

109

Portasystemic shunt fraction quantification with colonic iodine-123 iodoamphetamine  

SciTech Connect

Portasystemic shunting was quantified in dogs with (/sup 123/I)iodoamphetamine (IMP) administered transrectally into the colon and monitored externally with a gamma camera. IMP was absorbed rapidly and unchanged from the colon. After direct injection into the portal vein, IMP was almost completely extracted by the liver on the first pass, and the washout half-life was approximately 60 min. Based on these kinetic data, computer simulation of this biologic system was carried out. Errors associated with simplified models are calculated. The simplest model with insignificant error, which assumed that the tracer behaved like microspheres, was used to quantitate portasystemic shunt fraction in animals with surgically created shunts. Results were compared with the standard of /sup 99m/Tc-labeled macroaggregated albumin infused into a branch of inferior mesenteric vein. For shunt fractions ranging from 0 to 100%, an excellent correlation was seen, indicating that this approach is potentially a simple, noninvasive method of portasystemic shunt fraction quantification.

Yen, C.K.; Pollycove, M.; Crass, R.; Lin, T.H.; Baldwin, R.; Lamb, J.

1986-08-01

110

Management of Ventriculo-Peritoneal Shunts in the Paediatric Population  

PubMed Central

The treatment of hydrocephalus is a challenging one. The development of shunt devices have greatly improved the survival and quality of life of paediatric patients with hydrocephalus; however, shunt dysfunction is a common problem which represents a significant scope of work for paediatric neurosurgeons with shunt failures occuring in up to 40 to 50% of patients during the first two years after shunt surgery. Numerous pathologies ranging from congenital to acquired conditions can result in the development of hydrocephalus in the paediatric population. Obstruction of proximal or distal catheter ends, misplacement, infections and over drainage are some of the common problems accounting for shunt failures. We discussed some of the pertinent problems and nuances involved in treatment of paediatric hydrocephalus with VPS as well as to review the role of endoscopic procedures as an alternative to VPS. PMID:22028738

Low, David; Drake, James M; Seow, Wan Tew; Ng, Wai Hoe

2010-01-01

111

Fabrication and characterization of shunted ?-SQUID  

SciTech Connect

In order to eliminate hysteresis, we have fabricated and characterized niobium based shunted micron size superconducting quantum interference devices (?-SQUIDs). We find a wide temperature range where these ?-SQUIDs are non-hysteretic in nature and show a very good I{sub c} vs. B oscillations in hysteretic regime and V vs. B oscillations in non-hysteretic regime. Here we report the characteristics of a shunted- ?-SQUID (Wf38LS72D5). In this device we have achieved a large voltage modulation, in non-hysteretic regime, at various temperatures including such as 1.1 mV at 6.62 K with a transfer function V{sub ?}?=?7.2mV/?{sub 0}. The figures within the original article PDF file, as supplied to AIP Publishing, were affected by a PDF-processing error. Consequently, the article re-flowed and pagination increased from 3 to 4 pages. This article was updated on 14 May 2014 to correct the PDF-processing error, with the scientific content remaining unchanged. Readers are advised that the replacement article PDF file contains an additional blank page to preserve the original pagination.

Kumar, Nikhil, E-mail: knikhil@iitk.ac.in [Department of Physics, Indian Institute of Technology Kanpur - 208016 (India); Fournier, T.; Courtois, H.; Gupta, Anjan K. [Institute Neel, CNRS and Université Joseph Fourier, 25 Avenue des Martyrs, BP 166, 38042, Grenoble (France)

2014-04-24

112

Shunt malfunction presenting with symptomatic syringomyelia: Demonstrated on contrast ventriculogram.  

PubMed

Ventriculoperitoneal (VP) shunt malfunction commonly presents as raised intracranial pressure. Rarely, when the central canal of the spinal cord communicates with the 4(th) ventricle, shunt malfunction can present as an expanding syrinx. The diagnosis is often delayed, resulting in severe morbidity. Some of these patients undergo repeated syrinx surgeries without much benefits. We report a case of chronic tuberculous meningitis with shunt malfunction presenting as an expanding spinal canal syrinx and quadriparesis. Fourth ventricular communication with syrinx was demonstrated with the help of a contrast ventriculogram. After shunt revision, syrinx resolved completely and the patient made significant improvement in his neurological deficits. The present case illustrates that a historical and rarely used investigation like contrast ventriculogram aids in the diagnosis and management even in the current neurosurgical practice. All patients with late onset syrinx and a previous VP shunt need to be investigated for shunt malfunction before considering syrinx surgery. A simple shunt revision resolves the syrinx in such conditions and avoids more complex procedures like Foramen magnum decompression. Relevant literature has been reviewed; pathophysiology and management options have been discussed. PMID:25250067

Aniruddha, T J; Pruthi, Nupur

2014-05-01

113

Laparoscopy for ventriculoperitoneal shunt implantation and revision surgery  

PubMed Central

Ventriculoperitoneal shunting (VPS) is a widely accepted technique for the treatment of hydrocephalus. The probability of shunt dysfunction is pretty high throughout life. Laparoscopy has become a valuable tool to perform VPS and treat abdominal complications. An electronic literature search was performed to reveal the published data relating laparoscopy and ventriculoperitoneal shunt in Medline, Embase, Scielo and Lilacs databases. The keywords employed were “laparoscopy” OR “laparoscopic surgery” AND “ventriculoperitoneal shunt” OR “shunt” AND “surgery” OR “implantation” OR “revision” OR “complication”. No high quality trials were developed comparing conventional laparotomic incision vs laparoscopic approach. Both approaches have evolved and currently there are less invasive options for laparotomy, like periumbilical small incisions; and for laparoscopy, like smaller and less incisions. Operating room time, blood loss and hospital stay may be potentially smaller in laparoscopic surgery and complications are probably the same as laparotomy. In revision surgery for abdominal complications after VPS, visualization of whole abdominal cavity is fundamental to address properly the problem and laparoscopic approach is valuable once it is safe, fast and much less invasive than laparotomy. Ventriculoperitoneal shunting is a widely accepted technique for the treatment of hydrocephalus. Laparoscopy assisted shunt surgery in selected cases might be a less invasive and more effective option for intrabdominal manipulation. The laparoscopic approach allows a better catheter positioning, lysis of fibrotic bundles and peritoneal inspection as well, without any additional complication. PMID:25228943

Pinto, Fernando Campos Gomes; de Oliveira, Matheus Fernandes

2014-01-01

114

Shunt malfunction presenting with symptomatic syringomyelia: Demonstrated on contrast ventriculogram  

PubMed Central

Ventriculoperitoneal (VP) shunt malfunction commonly presents as raised intracranial pressure. Rarely, when the central canal of the spinal cord communicates with the 4th ventricle, shunt malfunction can present as an expanding syrinx. The diagnosis is often delayed, resulting in severe morbidity. Some of these patients undergo repeated syrinx surgeries without much benefits. We report a case of chronic tuberculous meningitis with shunt malfunction presenting as an expanding spinal canal syrinx and quadriparesis. Fourth ventricular communication with syrinx was demonstrated with the help of a contrast ventriculogram. After shunt revision, syrinx resolved completely and the patient made significant improvement in his neurological deficits. The present case illustrates that a historical and rarely used investigation like contrast ventriculogram aids in the diagnosis and management even in the current neurosurgical practice. All patients with late onset syrinx and a previous VP shunt need to be investigated for shunt malfunction before considering syrinx surgery. A simple shunt revision resolves the syrinx in such conditions and avoids more complex procedures like Foramen magnum decompression. Relevant literature has been reviewed; pathophysiology and management options have been discussed. PMID:25250067

Aniruddha, T. J; Pruthi, Nupur

2014-01-01

115

Surgical shunts and tips for variceal decompression in the 1990s  

Microsoft Academic Search

Background. In the 1990s, liver transplantations and transjugular intrahepatic portosystemic shunts (TIPS) have become the most common methods to decompress portal hypertension. This center has continued to use surgical shunts for variceal bleeding in good-risk patients who continue to bleed through endoscopic and pharmacologic treatment. This article reports this center's experience with surgical shunts and TIPS shunts from 1992 through

J. Michael Henderson; Alexander Nagle; Susan Curtas; Michael Geisinger; David Barnes

2000-01-01

116

Baseline Neuropsychological Profile and Cognitive Response to Cerebrospinal Fluid Shunting for Idiopathic Normal Pressure Hydrocephalus  

Microsoft Academic Search

Objective: To evaluate neurocognitive changes and predict neurocognitive outcome after ventriculoperitoneal shunting for idiopathic normal pressure hydrocephalus (INPH). Background: Reports of neurocognitive response to shunting have been variable and studies that predict cognitive outcomes after shunting are limited. We reviewed our experience with cognitive outcomes for INPH patients who were selected for shunting based on abnormal cerebrospinal fluid (CSF) pressure

George Thomas; Matthew J. McGirt; Graeme Woodworth; Jennifer Heidler; Daniele Rigamonti; Argye E. Hillis; Michael A. Williams

2005-01-01

117

Remittent hyperammonemia in congenital portosystemic shunt.  

PubMed

Congenital portosystemic shunts (PSS) are rare vascular anomalies with different gross anatomy. Persistent patent ductus venosus (PDV) represents an uncommon cause of intrahepatic PSS. The diagnosis of this condition may not be obvious because of its wide spectrum of clinical manifestations, ranging from asymptomatic to life-threatening disease. We report the case of three boys with neuropsychological symptoms associated with mild fasting hyperammonemia. An oral protein load allowed the detection of a detoxication defect due to PSS related to PDV. This simple procedure can be worthwhile of attention in patients with mental retardation, behavior disturbances, and learning difficulties after exclusion of common causes of inherited hyperammonemia, namely, urea cycle disorders, organic acidemias, and fatty acid oxidation defects. PMID:19618212

Ferrero, Giovanni Battista; Porta, Francesco; Biamino, Elisa; Mussa, Alessandro; Garelli, Emanuela; Chiappe, Francesca; Veltri, Andrea; Silengo, Margherita Cirillo; Gennari, Fabrizio

2010-03-01

118

Ion beam sputter-etched ventricular catheter for hydrocephalus shunt  

NASA Technical Reports Server (NTRS)

A cerebrospinal fluid shunt in the form of a ventricular catheter for controlling the condition of hydrocephalus by relieving the excessive cerebrospinal fluid pressure is described. A method for fabrication of the catheter and shunting the cerebral fluid from the cerebral ventricles to other areas of the body is also considered. Shunt flow failure occurs if the ventricle collapse due to improper valve function causing overdrainage. The ventricular catheter comprises a multiplicity of inlet microtubules. Each microtubule has both a large openings at its inlet end and a multiplicity of microscopic openings along its lateral surfaces.

Banks, B. A. (inventor)

1983-01-01

119

Spontaneous intrahepatic portosystemic shunt managed by laparoscopic hepatic vein closure.  

PubMed

Intrahepatic portosystemic shunt (IPSS) is uncommon and usually follows trauma or iatrogenic injury, but spontaneous shunts may also occur, in patients without the evidence of chronic liver disease. Although interventional endovascular management of the shunts is the treatment of choice, a surgical approach can be used when the percutaneous approach fails. We report here a case of symptomatic spontaneous IPSS between the posteroinferior branch of right portal vein and the right inferior hepatic vein, which was successfully managed with laparoscopic closure of the hepatic vein. To the best of our knowledge, this is the first case report of laparoscopic management of spontaneous IPSS. PMID:25336823

Kwon, Jung-Nam; Jeon, Yong Sun; Cho, Soon-Gu; Lee, Keon-Young; Hong, Kee Chun

2014-10-01

120

Spontaneous intrahepatic portosystemic shunt managed by laparoscopic hepatic vein closure  

PubMed Central

Intrahepatic portosystemic shunt (IPSS) is uncommon and usually follows trauma or iatrogenic injury, but spontaneous shunts may also occur, in patients without the evidence of chronic liver disease. Although interventional endovascular management of the shunts is the treatment of choice, a surgical approach can be used when the percutaneous approach fails. We report here a case of symptomatic spontaneous IPSS between the posteroinferior branch of right portal vein and the right inferior hepatic vein, which was successfully managed with laparoscopic closure of the hepatic vein. To the best of our knowledge, this is the first case report of laparoscopic management of spontaneous IPSS. PMID:25336823

Kwon, Jung-Nam; Jeon, Yong Sun; Cho, Soon-Gu; Lee, Keon-Young; Hong, Kee Chun

2014-01-01

121

Imaging diagnosis--Complex intrahepatic portosystemic shunt in a dog.  

PubMed

An unusual form of congenital intrahepatic portosystemic shunt was identified in a 3 1/2-month-old female Labrador Retriever with neurologic signs. Ultrasonography and contrast-enhanced computed tomography were used to characterize the shunt morphology. An unusual, looping right-divisional shunt connected back to the portal vein that formed an ampula in the right-central portion of the liver. An irregularly shaped window-like opening connected the combined right-divisional loop and aneurysmal portal vein, and the caudal vena cava, while this vascular pool gradually fused more cranially. Imaging features of this complex vascular anomaly, which has not been previously reported, are presented. PMID:18251295

D'Anjou, Marc-André; Huneault, Louis

2008-01-01

122

Endoscopic third ventriculostomy for malfunction in previously shunted infants  

Microsoft Academic Search

Introduction  The usage of endoscopic third ventriculostomy (ETV) as an alternative to shunt revision in the management of shunt malfunction\\u000a is gaining popularity.\\u000a \\u000a \\u000a \\u000a Methods  We review the clinical data of 45 patients who underwent ETV because of ventriculopritoneal shunt malfunction at Hacettepe\\u000a University School of Medicine Department of Neurosurgery between January 2002 and August 2007. Medical records of the patients\\u000a were retrospectively

Burçak Bilginer; Kader Karl? Oguz; Nejat Akalan

2009-01-01

123

7. May 1974. TOP OF THE CYLINDERS, LP (LEFT), HP ...  

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

7. May 1974. TOP OF THE CYLINDERS, LP (LEFT), HP (RIGHT) - Jones & Laughlin Steel Corporation, Pittsburgh Works, Morgan Billet Mill Engine, 550 feet north of East Carson Street, opposite South Twenty-seventh Street, Pittsburgh, Allegheny County, PA

124

Immunochemical quantification of human plasma Lp(a) lipoprotein  

Microsoft Academic Search

The Lp(a) lipoprotein was purified from human plasma by ultracentrifugation and gel filtration on 6% agarose. It contained\\u000a 27% protein, 65% lipid, and 8% carbohydrate. Quantification of the Lp(a) lipoprotein was performed by radial immunodiffusion.\\u000a Both within-assay and between-assay coefficients of variation were inversely concentration dependent, decreasing from 20%\\u000a and 27%, respectively, at 3 mg\\/100 ml to 7% and 12%,

John J. Albers; William R. Hazzard

1974-01-01

125

9. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

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

9. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

126

8. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

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

8. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

127

4. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

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

4. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

128

5. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

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

5. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

129

6. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

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

6. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

130

7. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL ...  

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

7. VIEW OF SHUNT LOCOMOTIVE NO. 9072 POSITIONING ELECTRIC DIESEL LOCOMOTIVE NO. 6734 ON TURNTABLE, adjacent to Erecting Shop and Machine Shop - Juniata Shops, Turntable, South of Sixth Street at Third Avemue, Altoona, Blair County, PA

131

Resolution of severe intrapulmonary shunting after liver transplantation.  

PubMed

A major complication of hepatic cirrhosis is arterial hypoxemia, often the result of intrapulmonary arteriovenous shunting. While previously such hypoxemia was thought to preclude successful hepatic transplantation, more recent studies have suggested that hepatic transplantation should be considered if the hypoxemia is corrected by supplemental oxygen. We report the findings in a cirrhotic patient with severe hypoxemia associated with intrapulmonary arteriovenous shunting. The patient did not respond to supplemental oxygen (PaO2 < 40 mm Hg on O2 at 4 L/min). The patient underwent successful hepatic transplantation, with complete resolution of intrapulmonary shunting. We believe that patients with cirrhosis-associated intrapulmonary shunting, even with hypoxemia resistant to supplemental oxygen, are acceptable candidates for hepatic transplantation. PMID:8131482

Schwarzenberg, S J; Freese, D K; Regelmann, W E; Gores, P F; Boudreau, R J; Payne, W D

1993-04-01

132

Vibration damping with shunted piezoceramics: Fundamentals and technical applications  

NASA Astrophysics Data System (ADS)

This paper describes the damping performance of shunted piezoceramics for passive LR-networks, negative capacitance shunts (LRC) and the SSDI-switching technique. The calculations are based on a general description for mechanical structures with piezoelectric elements. Normalized parameters are introduced and the damping performance described by the generalized electromechanical coupling coefficient. For every electrical shunting the optimal network parameters are determined and the resulting maximum damping is compared. Additionally, a squealing disc brake and a bladed disc model are studied as technical applications. Practical realizations for the inclusion of the piezoelements and measurements are presented which validate the calculated damping performance. In particular, it is shown that the shunted piezoceramics are capable to suppress the brake squealing.

Neubauer, Marcus; Wallaschek, Jörg

2013-03-01

133

Percutaneous intrahepatic portosystemic shunt created via a femoral vein approach.  

PubMed

Creation of a percutaneous intrahepatic portosystemic shunt was attempted in a patient with portal hypertension and acute variceal hemorrhage. Abnormal hepatic venous anatomy precluded formation of the shunt with the standard transjugular method. An alternate technique was devised in which a femoral vein approach was used to construct an intrahepatic channel between the inferior right hepatic vein and the right portal vein. The patient stopped bleeding after the procedure and has not rebled during an 8-month follow-up period. PMID:1947081

LaBerge, J M; Ring, E J; Gordon, R L

1991-12-01

134

Noncirrhotic portal vein thrombosis. Physiology before and after shunts.  

PubMed Central

Controversy exists concerning the proper therapy for bleeding gastroesophageal varices secondary to noncirrhotic portal vein thrombosis. Disparity of opinion exists regarding the significance of hepatic portal blood flow and the consequences of total portal-systemic shunts in this condition. One patient is presented who developed severe, crippling encephalopathy 20 years after a central splenorenal shunt. This was associated with loss of portal flow to the liver and marked nitrogen intolerance. Closure of the shunt resulted in restoration of hepatic portal flow via collateral veins (HPI 0.36), clearance of encephalopathy and return to near normal protein tolerance. An additional patient was studied with hyperammonemia and early suggestive signs of encephalopathy eight years following a mesocaval shunt. Four patients were evaluated before and after selective distal splenorenal shunts. All had "cavernous transformation" of the portal vein with angiographic evidence of portal flow to the liver. Postoperative angiograms revealed continued hepatic portal perfusion and a patent shunt in each patient. Radionuclide imaging postoperatively gave an estimated portal fraction of total hepatic blood flow (HPI) of .39 and .60 in two of the four patients. We conclude that 1) there is significant hepatic portal perfusion in noncirrhotic portal vein thrombosis (cavernous transformation), 2) loss of this hepatic portal flow following total shunts can lead to severe encephalopathy, 3) the selective distal splenorenal shunt maintains hepatic portal perfusion and is the procedure of choice when there is a patent splenic vein and surgical intervention is indicated. Images Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. Fig. 9a. Fig. 9b. Fig. 9c. PMID:7416830

Warren, W D; Millikan, W J; Smith, R B; Rypins, E B; Henderson, J M; Salam, A A; Hersh, T; Galambos, J T; Faraj, B A

1980-01-01

135

The use and misuse of transjugular intrahepatic portasystemic shunts  

Microsoft Academic Search

Transjugular intrahepatic portasystemic shunts, or TIPS, are used to create a low-resistance channel between the hepatic vein\\u000a and the intrahepatic portion of the portal vein by deployment of an expandable metal stent. TIPS function like side-to-side\\u000a surgical portacaval shunts, but their placement does not require anesthesia and major surgery. This article reviews the uses\\u000a and misuses of TIPS in current

Arun J. Sanyal

2000-01-01

136

Aberrant Gene Expression in Dogs with Portosystemic Shunts  

PubMed Central

Congenital portosystemic shunts are developmental anomalies of the splanchnic vascular system that cause portal blood to bypass the liver. Large-breed dogs are predisposed for intrahepatic portosystemic shunts (IHPSS) and small-breed dogs for extrahepatic portosystemic shunts (EHPSS). While the phenotype resulting from portal bypass of the liver of the two types of shunt is identical, the genotype and molecular pathways involved are probably different. The aim of this study was to gain insight into the pathways involved in the different types of portosystemic shunting. Microarray analysis of mRNA expression in liver tissue from dogs with EHPSS and IHPSS revealed that the expression of 26 genes was altered in either IHPSS or EHPSS samples compared with that in liver samples from control dogs. Quantitative real-time PCR of these genes in 14 IHPSS, 17 EHPSS, and 8 control liver samples revealed a significant differential expression of ACBP, CCBL1, GPC3, HAMP, PALLD, VCAM1, and WEE1. Immunohistochemistry and Western blotting confirmed an increased expression of VCAM1 in IHPSS but its absence in EHPSS, an increased WEE1 expression in IHPSS but not in EHPSS, and a decreased expression of CCBL1 in both shunt types. Regarding their physiologic functions, these findings may indicate a causative role for VCAM1 in IHPSS and WEE1 for IHPSS. CCBL1 could be an interesting candidate to study not yet elucidated aspects in the pathophysiology of hepatic encephalopathy. PMID:23451256

Grinwis, Guy C. M.; Kummeling, Anne; van Gils, Ingrid H. M.; Koerkamp, Marian J. A. Groot.; van Leenen, Dik; Holstege, Frank C. P.; Penning, Louis C.; Rothuizen, Jan; Leegwater, Peter A. J.; Spee, Bart

2013-01-01

137

Aberrant gene expression in dogs with portosystemic shunts.  

PubMed

Congenital portosystemic shunts are developmental anomalies of the splanchnic vascular system that cause portal blood to bypass the liver. Large-breed dogs are predisposed for intrahepatic portosystemic shunts (IHPSS) and small-breed dogs for extrahepatic portosystemic shunts (EHPSS). While the phenotype resulting from portal bypass of the liver of the two types of shunt is identical, the genotype and molecular pathways involved are probably different. The aim of this study was to gain insight into the pathways involved in the different types of portosystemic shunting. Microarray analysis of mRNA expression in liver tissue from dogs with EHPSS and IHPSS revealed that the expression of 26 genes was altered in either IHPSS or EHPSS samples compared with that in liver samples from control dogs. Quantitative real-time PCR of these genes in 14 IHPSS, 17 EHPSS, and 8 control liver samples revealed a significant differential expression of ACBP, CCBL1, GPC3, HAMP, PALLD, VCAM1, and WEE1. Immunohistochemistry and Western blotting confirmed an increased expression of VCAM1 in IHPSS but its absence in EHPSS, an increased WEE1 expression in IHPSS but not in EHPSS, and a decreased expression of CCBL1 in both shunt types. Regarding their physiologic functions, these findings may indicate a causative role for VCAM1 in EHPSS [corrected] and WEE1 for IHPSS. CCBL1 could be an interesting candidate to study not yet elucidated aspects in the pathophysiology of hepatic encephalopathy. PMID:23451256

van Steenbeek, Frank G; Van den Bossche, Lindsay; Grinwis, Guy C M; Kummeling, Anne; van Gils, Ingrid H M; Koerkamp, Marian J A Groot; van Leenen, Dik; Holstege, Frank C P; Penning, Louis C; Rothuizen, Jan; Leegwater, Peter A J; Spee, Bart

2013-01-01

138

Urethrocutaneous fistula post-Al-Ghorab shunt  

PubMed Central

Priapism is a rare event that may be induced by clinical conditions and medications. Ischemic priapism (IP) is a compartment syndrome of the penis, and it constitutes a medical emergency that may cause significant morbidity on the erectile function in particular. We report a case of a 30-year-old male in his fourth episode of priapism. The aspiration and washing of the corpora cavernosa with saline solution were performed, followed by washing with adrenaline solution without resolution of the condition. Treatment was followed by the performance of the Al-Ghorab shunt procedure with dorsal incision of the glans. During follow-up, an area of necrosis distal to the incision was detected, and after the catheter removal on postoperative day 14, the patient developed a glandular dorsal urethrocutaneous fistula and meatal stenosis. The meatal stenosis was corrected by Johanson urethroplasty with a neo-meatus at the coronal sulcus, along with resection and debridement of the fistula tract and a three-layer closure. PMID:25210568

Paladino, João Roberto; Wroclawski, Marcelo; Den Julio, Alexandre; Teixeira, Gabriel Kushyama; Glina, Sidney; Lima Pompeo, Antonio Carlos

2014-01-01

139

LP DAAC and MEaSUREs - Optimizing Collection Inception  

NASA Astrophysics Data System (ADS)

The Land Processes Distributed Active Archive Center (LP DAAC) is a selected NASA Earth Observing System (EOS) Data and Information System (EOSDIS) DAAC supporting the Making Earth System Data Records for Use in Research Environments (MEaSUREs) Program to contribute in providing long-term, consistent, and mature data products. The LP DAAC has identified three essential components for the MEaSUREs collection inception. The first component includes a framework of LP DAAC's data lifecycle including overall inception of products, curation of products, and long-term archiving of products. The second component fuses data producer and data provider operations, interleaving key personnel into key processes throughout the project. The third component integrates and evolves stakeholder elements into a standard methodology, alongside affording an overall homogeneous data delivery system for MEaSUREs collections. As an active participant on the Metadata Evolution for NASA Data Systems (MENDS) Tiger Team, the LP DAAC is working to categorize all data model elements into the ISO 19115 international metadata standard. This poster depicts how each of these three components optimizes the LP DAAC MEaSUREs collection inception process.

Bennett, S.

2013-12-01

140

Attenuation of Congenital Portosystemic Shunt Reduces Inflammation in Dogs  

PubMed Central

Liver disease is a major cause of morbidity and mortality. One of the most significant complications in patients with liver disease is the development of neurological disturbances, termed hepatic encephalopathy. The pathogenesis of hepatic encephalopathy is incompletely understood, which has resulted in the development of a wide range of experimental models. Congenital portosystemic shunt is one of the most common congenital disorders diagnosed in client owned dogs. Our recent studies have demonstrated that the pathophysiology of canine hepatic encephalopathy is very similar to human hepatic encephalopathy, which provides strong support for the use of dogs with a congenital portosystemic shunt as a naturally occurring model of human hepatic encephalopathy. Specifically, we have demonstrated an important role for ammonia and inflammation in the development of hepatic encephalopathy in dogs with a congenital portosystemic shunt. Despite the apparent importance of inflammation in driving hepatic encephalopathy in dogs, it is unclear whether inflammation resolves following the successful treatment of liver disease. We hypothesized that haematological and biochemical evidence of inflammation, as gauged by neutrophil, lymphocyte and monocyte concentrations together with C-reactive protein concentrations, would decrease following successful treatment of congenital portosystemic shunts in dogs. One hundred and forty dogs with a congenital portosystemic shunt were enrolled into the study. We found that the proportion of dogs with a monocyte concentration above the reference range was significantly greater in dogs with hepatic encephalopathy at time of initial diagnosis. Importantly, neutrophil and monocyte concentrations significantly decreased following surgical congenital portosystemic shunt attenuation. We also found a significant decrease in C-reactive protein concentrations following surgical attenuation of congenital portosystemic shunts. Our study demonstrates that haematological and biochemical indices of inflammation reduce following successful treatment of the underlying liver disorder. PMID:25658922

Tivers, Michael S.; Handel, Ian; Gow, Adam G.; Lipscomb, Victoria J.; Jalan, Rajiv; Mellanby, Richard J.

2015-01-01

141

Valve Pressure Upgrade May Produce Progressive Deterioration of Vision in Children with Slit Ventricle Syndrome  

Microsoft Academic Search

Recently, valve upgrade and\\/or endoscopic third ventriculostomy, which have the merit of no additional shunting, were introduced for the treatment of slit ventricle syndrome, because lumboperitoneal shunting entails various complications including development of Chiari malformation, shunt malfunction, and infection. However, the safety of valve upgrading is not confirmed, especially in a child with slit ventricle syndrome developed as a result

Seoung Woo Park; Soo Han Yoon; Ki Hong Cho; Yong Sam Shin

2007-01-01

142

1. RN p R 1 p g1,...,gN Lp()  

E-print Network

22080119 : 1. RN p R 1 p W1,p() W1,p() = u Lp() ; g1,...,gN Lp() u xi dx = - gidx for C c () i = 1,...,N u W1,p() u xi = gi u = grad u = ( u x1 ,..., u xN ) W1,p() u W1,p()= u Lp() + N i=1 u xi Lp() ( ( u p Lp() +N i=1 u xi p Lp() ) 1 p ) 1 = B1 = {x R2 ; |x| p = 1 u

Ishii, Hitoshi

143

The long-term prognosis of congenital portosystemic venous shunt.  

PubMed

Congenital portosystemic venous shunt (PSVS), considered to be a rare disease, can lead to hepatic encephalopathy (HE). With improvements in diagnostic imaging techniques, the number of infants and children with documented PSVS has increased. The natural course of the disease and indications for surgical closure of the shunt vessel have not been well defined. We reviewed 51 cases of congenital PSVS in Japan; 34 patients had an intrahepatic PSVS, and 17 had an extrahepatic PSVS. There were 12 patients with HE at the time of diagnosis. The frequency of HE increased in subjects over 60 years of age. Children with HE had a shunt ratio exceeding 60%. When the shunt ratio was less than 30%, HE did not occur. Twenty of 28 patients under the age of 15 years had hypergalactosemia at the time of neonatal screening. Part of the congenital intrahepatic PSVS spontaneously closed. Surgical closure of a PSVS may be an approach expected to prevent HE when the shunt ratio exceeds 60%. PMID:10431123

Uchino, T; Matsuda, I; Endo, F

1999-08-01

144

The Intermediate Age Brown Dwarf LP 944-20  

Microsoft Academic Search

Observations are presented which show that LiI 6708A is detected with\\u000aequivalent width of 0.53+-0.05A in the proper-motion object LP 944-20 (which is\\u000aalso known as BRI 0337-3535). This Li detection implies that LP 944-20 is a\\u000abrown dwarf with mass between 0.057 and 0.063Mo and age between 475 and 650Myr,\\u000amaking it the first brown dwarf to have its

C. G. Tinney

1998-01-01

145

The Intermediate Age Brown Dwarf LP 944-20  

E-print Network

Observations are presented which show that LiI 6708A is detected with equivalent width of 0.53+-0.05A in the proper-motion object LP 944-20 (which is also known as BRI 0337-3535). This Li detection implies that LP 944-20 is a brown dwarf with mass between 0.057 and 0.063Mo and age between 475 and 650Myr, making it the first brown dwarf to have its mass and age precisely determined.

C. G. Tinney

1998-01-17

146

Vibration Isolation using a Shunted Electromagnetic S. Behrens, A. J. Fleming, S. O. R. Moheimani  

E-print Network

Vibration Isolation using a Shunted Electromagnetic Transducer S. Behrens, A. J. Fleming, S. O. R transducer, and actuate using an electromagnetic transducer. Electromagnetic transducers can be used ABSTRACT By attaching an electromagnetic transducer to a mechanical isolation system and shunting

Fleming, Andrew J.

147

Predicting shunt currents in stacks of bipolar plate cells  

NASA Astrophysics Data System (ADS)

A method is presented for predicting shunt currents in stacks of undivided and divided bipolar plate cells. The method is an efficient way of solving the coupled sets of algebraic equations that arise from using circuit analog models to represent the current paths in stacks of undivided or divided bipolar plate cells. These algebraic equations can be either linear or nonlinear depending upon the current-potential relationships used in the model (i.e., nonlinear circuit elements can be included). The method is used to show the importance of including nonsymmetrical resistances and nonlinear circuit elements in the models. Also, the method is used to predict the shunt currents for a nine cell stack of pilot plant scale bipolar plate, membrane chlor-alkali cells. It is shown that these predictions agree qualitatively with measured values. Finally, the method is used to predict the shunt currents for stacks of 60 and 120 of these cells.

White, R. E.; Walton, C. W.; Burney, H. S.; Beaver, R. N.

1986-03-01

148

Acute Shunt Malfunction after Cesarean Section Delivery: A Case Report  

PubMed Central

Shunt malfunctions that require surgical intervention during pregnancy and the postpartum period are rare. Furthermore, no study has reported on an acute shunt malfunction immediately after cesarean section. Here, we describe the case of a 32-yr-old woman who became drowsy 12 hr after cesarean section delivery of her second child. She had a ventriculoperitoneal shunt placed to treat hydrocephalus associated with meningitis at 26 yr of age. Marked ventriculomegaly was seen on brain computed tomography and her consciousness recovered temporarily after aspirating cerebrospinal fluid from the flushing device. At surgery, the distal catheter tip was plugged by a blood clot. We believe that the blood spilled over during the cesarean section. The clogged catheter end was simply cut off and the remaining catheter was repositioned in the peritoneal cavity. Her consciousness recovered fully. PMID:20358015

Kim, Tae-Hee; Kim, Bum-Tae; Im, Soo-Bin; Shin, Won-Han

2010-01-01

149

Temporal and spatial distributions of carbon shunting arc plasma  

NASA Astrophysics Data System (ADS)

The temporal and spatial distributions of a magnetically driven shunting arc plasma were obtained using time-resolved probe measurement. A shunting arc was produced using a carbon rod and accelerated along a pair of rail electrodes by a Lorenz force. The pulse current for driving and maintaining the plasma was supplied from a 20 µF capacitor charged by a dc power supply. Double and single probes were employed to obtain the ion density of the shunting arc plasma. An ion density of 1 × 1019 m?3 was obtained at a distance of 50 mm from the carbon rod 15 µs after applying voltage. The ion density decreased to 2.0 × 1018 m?3 with increasing distance from 50 to 150 mm. The ion density changed with the energy inputted into the plasma.

Takaki, Koichi; Konishi, Takumi; Mikawa, Ryota; Takahashi, Kazunori; Yukimura, Ken

2015-01-01

150

Treatment of Portosystemic Shunt Myelopathy with a Stent Graft Deployed through a Transjugular Intrahepatic Route  

SciTech Connect

A case of surgically created splenorenal shunt complicated with shunt myelopathy was successfully managed by placement of a stent graft within the splenic vein to close the portosystemic shunt and alleviate myelopathy. To our knowledge, this is the first report of a case of shunt myelopathy in a patient with noncirrhotic portal fibrosis without cirrhosis treated by a novel technique wherein a transjugular intrahepatic route was adopted to deploy the stent graft.

Jain, Deepak, E-mail: deepakjain02@yahoo.com; Arora, Ankur, E-mail: aroradrankur@yahoo.com [Institute of Liver and Biliary Sciences, Department of Radiology (India); Deka, Pranjal, E-mail: drpranjaldeka@gmail.com [Institute of Liver and Biliary Sciences, Department of Hepatopancreatobiliary Surgery (India); Mukund, Amar, E-mail: dramarmukund@gmail.com; Bhatnagar, Shorav, E-mail: drshorav@yahoo.com [Institute of Liver and Biliary Sciences, Department of Radiology (India); Jindal, Deepti, E-mail: deepijindal@rediffmail.com; Kumar, Niteen, E-mail: drniteenkumar@gmail.com; Pamecha, Viniyendra, E-mail: viniyendra@yahoo.co.uk [Institute of Liver and Biliary Sciences, Department of Hepatopancreatobiliary Surgery (India)

2013-08-01

151

Maternal postpartum Group B Beta-hemolytic streptococcus ventriculoperitoneal shunt infection  

Microsoft Academic Search

Background. Women with cerebrospinal fluid shunts require special management during the course of pregnancy. Case report. We describe a case of delayed postpartum ventriculoperitoneal shunt infection by Group B streptococcus in a 19-year-old who presented complaining of headache and a fever. The CSF culture from the shunt tap and the distal shunt tip both grew Group B Beta-hemolytic streptococcus. Conclusion.

Jason M. Kane; Kevin Jackson; James H. Conway

2004-01-01

152

Fetal ovarian cyst mimicking a CSF pseudocyst in the setting of shunt failure.  

PubMed

Fetal ovarian cysts are common congenital lesions encountered in the neonatal population. These cysts are typically benign and rarely require any invasive intervention. Abdominal pseudocyst formation as a result of a ventriculoperitoneal shunt is a relatively infrequent occurrence and is similarly an uncommon cause of shunt failure. The authors present the case of a 4-month-old girl with shunted hydrocephalus who presented with shunt failure from a suspected abdominal pseudocyst that was found to be a fetal ovarian cyst. PMID:25343733

Calayag, Mark; Malone, Christian Cantillano; Drake, Brian; Chavhan, Govind; Rutka, James T

2015-01-01

153

[Shunt surgery versus disconnection in portal hypertension. A comparative study].  

PubMed

Controversy remains about the best treatment for patients with esophagogastric variceal bleeding. In spite of different therapeutic alternatives and recent progress, such as liver transplantation of TIPS, many patients will finally be treated by standard surgery. With the aim to know the results of surgery in shunting vs non-shunting procedures, we have analyzed a recent and consecutive series of 68 cirrhotics patients operated on for variceal hemorrhage. According to the surgical technique there were three groups: I) 30 patients underwent a total portacaval shunt; II) 18 cases with an azygosportal disconnection; III) 20 patients with a partial portacaval shunt (8-10 mm H-portacaval PTFE graft). All groups were homogeneous considering age, sex etiology, Child-Pugh grade and timing of surgery (elective vs urgent). The complications and mortality rates were similar for the three groups. The overall operative mortality was 10%, and 5% in selected cases (Child-Pugh A-B, non urgent cases). With a follow-up for I, II and III group of 47, 44 and 27 months respectively, chronic encephalopathy have been seen in 61%, 15% and 15% respectively (p < .05). No patient in group I has rebled, and only one case in the II and III groups had a recurrence of hemorrhage. The actuarial three years survival was 76%, 86% and 85% (p NS), and the five year survival was 41% vs 86% for the groups I and II respectively (p < .05). In conclusion, in selected cases, surgery gives excellent immediate and long term results. In patients with variceal bleeding and failure of first line treatments, such as sclerosis or pharmacology, the partial H-portacaval shunt and non-shunting procedures are good alternatives, with low incidence of rebleeding and chronic encephalopathy. PMID:9004798

Bondía, J A; Santoyo, J; Fernández-Aguilar, J L; Marín, R; Suarez, M A; Caro, J A; Jiménez, M; Caparrós, R; Ribeiro, M; de la Fuente, A

1996-04-01

154

Shunted Piezoelectric Vibration Damping Analysis Including Centrifugal Loading Effects  

NASA Technical Reports Server (NTRS)

Excessive vibration of turbomachinery blades causes high cycle fatigue problems which require damping treatments to mitigate vibration levels. One method is the use of piezoelectric materials as passive or active dampers. Based on the technical challenges and requirements learned from previous turbomachinery rotor blades research, an effort has been made to investigate the effectiveness of a shunted piezoelectric for the turbomachinery rotor blades vibration control, specifically for a condition with centrifugal rotation. While ample research has been performed on the use of a piezoelectric material with electric circuits to attempt to control the structural vibration damping, very little study has been done regarding rotational effects. The present study attempts to fill this void. Specifically, the objectives of this study are: (a) to create and analyze finite element models for harmonic forced response vibration analysis coupled with shunted piezoelectric circuits for engine blade operational conditions, (b) to validate the experimental test approaches with numerical results and vice versa, and (c) to establish a numerical modeling capability for vibration control using shunted piezoelectric circuits under rotation. Study has focused on a resonant damping control using shunted piezoelectric patches on plate specimens. Tests and analyses were performed for both non-spinning and spinning conditions. The finite element (FE) shunted piezoelectric circuit damping simulations were performed using the ANSYS Multiphysics code for the resistive and inductive circuit piezoelectric simulations of both conditions. The FE results showed a good correlation with experimental test results. Tests and analyses of shunted piezoelectric damping control, demonstrating with plate specimens, show a great potential to reduce blade vibrations under centrifugal loading.

Min, James B.; Duffy, Kirsten P.; Provenza, Andrew J.

2011-01-01

155

77 FR 74280 - Proposed Information Collection (Learner's Perception (LP) Survey); Comment Request  

Federal Register 2010, 2011, 2012, 2013, 2014

...Information Collection (Learner's Perception (LP) Survey); Comment Request AGENCY...information technology. Title: Learner's Perception (LP) Survey, VA Form 10-0439...be use to obtain health care trainees perception of their clinical experience with...

2012-12-13

156

78 FR 11965 - Agency Information Collection (Learner's Perception (LP) Survey) Activities Under OMB Review  

Federal Register 2010, 2011, 2012, 2013, 2014

...Information Collection (Learner's Perception (LP) Survey) Activities Under OMB...SUPPLEMENTARY INFORMATION: Title: Learner's Perception (LP) Survey, VA Form 10-0439...be use to obtain health care trainees perception of their clinical experience with...

2013-02-20

157

77 FR 44432 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held...directive (AD) for certain Gulfstream Aerospace LP (Type Certificate previously held...FURTHER INFORMATION CONTACT: Tom Groves, Aerospace Engineer, International Branch,...

2012-07-30

158

76 FR 30294 - Special Conditions: Gulfstream Aerospace LP (GALP) Model G250 Airplane Pilot Compartment View...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Notice No. 25-11-14-SC] Special Conditions: Gulfstream Aerospace LP (GALP) Model G250 Airplane Pilot Compartment View...This action proposes special conditions for the Gulfstream Aerospace LP (GALP) Model G250 airplane. This airplane will...

2011-05-25

159

78 FR 11567 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held...airworthiness directive (AD) for all Gulfstream Aerospace LP (Type Certificate Previously Held...FURTHER INFORMATION CONTACT: Tom Groves, Aerospace Engineer, International Branch,...

2013-02-19

160

77 FR 58323 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held...airworthiness directive (AD) for all Gulfstream Aerospace LP (Type Certificate Previously Held...this proposed AD, contact Gulfstream Aerospace Corporation, P.O. Box 2206,...

2012-09-20

161

77 FR 64767 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held...directive (AD) for certain Gulfstream Aerospace LP (Type Certificate previously held...FURTHER INFORMATION CONTACT: Tom Groves, Aerospace Engineer, International Branch,...

2012-10-23

162

77 FR 44113 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held...directive (AD) for certain Gulfstream Aerospace LP (Type Certificate previously held...identified in this AD, contact Gulfstream Aerospace Corporation, P.O. Box 2206,...

2012-07-27

163

77 FR 32069 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held...directive (AD) for certain Gulfstream Aerospace LP (Type Certificate previously held...this proposed AD, contact Gulfstream Aerospace Corporation, P.O. Box 2206,...

2012-05-31

164

78 FR 47546 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held...AD) 2010-11-02 for all Gulfstream Aerospace LP (Type Certificate Previously Held...INFORMATION CONTACT: Tom Stafford, Aerospace Engineer, International Branch,...

2013-08-06

165

77 FR 21764 - Shell Pipeline Company LP; Notice of Petition for Declaratory Order  

Federal Register 2010, 2011, 2012, 2013, 2014

...Energy Regulatory Commission [Docket No. OR12-11-000] Shell Pipeline Company LP; Notice of Petition for Declaratory Order...that on March 30, 2012, pursuant to Rule 207(a)(2), Shell Pipeline Company LP (SPLC) submitted a petition...

2012-04-11

166

77 FR 50492 - Notice of Petition for Declaratory Order; Shell Pipeline Company LP  

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket No. OR12-23-000] Notice of Petition for Declaratory Order; Shell Pipeline Company LP Take notice that on August 10, 2012, pursuant to Rule 207(a)(2), Shell Pipeline Company LP submitted a petition requesting that the...

2012-08-21

167

Fire Service Training. LP and Compressed Gas Emergencies.  

ERIC Educational Resources Information Center

Part of a series of instructional outlines intended for use in a training program for firemen with no previous formal training, this curriculum guide discusses safety precautions for liquefied petroleum (LP) and compressed gas emergencies. During its twelve hours of instruction it covers (1) terminology; (2) the chemical composition of the gases;…

North Carolina State Dept. of Community Colleges, Raleigh.

168

Dextran-sulfate cellulose adsorption for lowering Lp[a].  

PubMed

Dextran sulfate selectively adsorbs lipoproteins that contain apolipoprotein-B100, including those associated with apolipoprotein-a, from human plasma with high affinity. Dextran sulfate immobilized on cellulose is incorporated into the Liposorber LA-15 system (Kaneka Corporation, Osaka, Japan). This system was evaluated in a nine-center controlled study of patients with familial hypercholesterolemia (FH) who had not responded adequately to diet and drug therapy. There were 54 patients with heterozygous FH: 45 randomized to treatment, 9 controls) and 10 patients with homozygous FH, all of whom received LDL apheresis. Removal of both LDL and Lp[a] was specific and highly efficient, > 90% of theory. Plasma LDL and Lp[a] concentrations were effectively lowered by repetitive LDL apheresis during the study and returned to baseline levels 3 to 4 weeks after the last apheresis treatment. The kinetics of the LDL rebound fit a simple one-pool kinetic model with a constant synthetic rate and constant fractional catabolic rate. The kinetics of the Lp[a] rebound are more complex and may require a model that includes a large extravascular Lp[a] pool in slow equilibrium with the plasma pool. PMID:8187231

Parker, T S

1994-01-01

169

US EPA Testing of LP & MP UV Disinfection Technologies  

EPA Science Inventory

Presentation will discuss the ongoing USEPA research on UV disinfection addressing the following objectives: Conservatively predict log inactivation and RED of adenovirus with surrogates; Conduct many (LP=61) UV reactor conditions challenged with Ad2, B. pumilus, and MS2 & conduc...

170

PuLP: A Linear Programming Toolkit for Python  

E-print Network

Sep 5, 2011 ... are natural to the Python language, avoiding special syntax and keywords ... Several factors were considered in the design of PuLP and in the selection of .... AMPL and Pyomo, we need to do this before defining the model.

2011-09-05

171

Protein adsorption to hydrocephalus shunt catheters: CSF protein adsorption  

PubMed Central

OBJECTIVE—To assess the quantity and nature of the proteins that adsorb to hydrocephalus shunt catheters after implantation, and to determine whether sufficient could accumulate to obstruct the catheter.?DESIGN—Elution of proteins from 102 explanted shunt catheters, with protein assay and electrophoresis of the eluate, and scanning electron microscopy (SEM) of the catheters.?RESULTS—The amount of protein elutable was extremely low, and significant protein, apart from a thin film, was not found on SEM. Qualitative analysis disclosed that most of the adsorbed protein was albumin.?CONCLUSIONS—Protein deposition on hydrocephalus catheters does not occur in sufficient quantities to cause catheter obstruction.?? PMID:9598681

Brydon, H.; Keir, G.; Thompson, E.; Bayston, R.; Hayward, R.; Harkness, W.

1998-01-01

172

Successful Embolization of a Spontaneous Mesocaval Shunt Using the Amplatzer Vascular Plug II  

Microsoft Academic Search

A 48-year-old man with alcoholic liver cirrhosis and hepatic encephalopathy was found to have a large, spontaneous mesocaval shunt. The shunt was successfully occluded with the use of an Amplatzer Vascular Plug. To our knowledge, this is the first report of the use of this device to embolize a mesocaval shunt involving the superior mesenteric vein.

Helena Boixadera; Alejandro Tomasello; Sergi Quiroga; Joan Cordoba; Mercedes Perez; Antoni Segarra

2010-01-01

173

Successful embolization of a spontaneous mesocaval shunt using the Amplatzer Vascular Plug II.  

PubMed

A 48-year-old man with alcoholic liver cirrhosis and hepatic encephalopathy was found to have a large, spontaneous mesocaval shunt. The shunt was successfully occluded with the use of an Amplatzer Vascular Plug. To our knowledge, this is the first report of the use of this device to embolize a mesocaval shunt involving the superior mesenteric vein. PMID:19908090

Boixadera, Helena; Tomasello, Alejandro; Quiroga, Sergi; Cordoba, Joan; Perez, Mercedes; Segarra, Antoni

2010-10-01

174

Distribution of extrahepatic congenital portosystemic shunt morphology in predisposed dog breeds  

PubMed Central

Background An inherited basis for congenital extrahepatic portosystemic shunts (EHPSS) has been demonstrated in several small dog breeds. If in general both portocaval and porto-azygous shunts occur in breeds predisposed to portosystemic shunts then this could indicate a common genetic background. This study was performed to determine the distribution of extrahepatic portocaval and porto-azygous shunts in purebred dog populations. Results Data of 135 client owned dogs diagnosed with EHPSS at the Faculty of Veterinary Medicine of Utrecht University from 2001 – 2010 were retrospectively analyzed. The correlation between shunt localization, sex, age, dog size and breed were studied. The study group consisted of 54 males and 81 females from 24 breeds. Twenty-five percent of dogs had porto-azygous shunts and 75% had portocaval shunts. Of the dogs with porto-azygous shunts only 27% was male (P?=?0.006). No significant sex difference was detected in dogs with a portocaval shunt. Both phenotypes were present in almost all breeds represented with more than six cases. Small dogs are mostly diagnosed with portocaval shunts (79%) whereas both types are detected. The age at diagnosis in dogs with porto-azygous shunts was significantly higher than that of dogs with portocaval shunts (P?

2012-01-01

175

Piezoelectric shunts with a parallel RL circuit for structural damping and vibration control  

Microsoft Academic Search

A study has been made of piezoelectric shunts using a piezoelectric element shunted with a parallel resistor and inductor circuit for passive structural damping and vibration control. It is found that under the optimum tuning condition, the peak amplitude of the displacement versus frequency curve of a structural mode decreases with the increase of the shunt resistance. It becomes a

Shu-Yau Wu

1996-01-01

176

Successful Embolization of a Spontaneous Mesocaval Shunt Using the Amplatzer Vascular Plug II  

SciTech Connect

A 48-year-old man with alcoholic liver cirrhosis and hepatic encephalopathy was found to have a large, spontaneous mesocaval shunt. The shunt was successfully occluded with the use of an Amplatzer Vascular Plug. To our knowledge, this is the first report of the use of this device to embolize a mesocaval shunt involving the superior mesenteric vein.

Boixadera, Helena, E-mail: hboixadera@hotmail.co [Hospital Vall d' Hebron, Department of Radiology (Spain); Tomasello, Alejandro [Hospital Vall d' Hebron, Department of Interventional Radiology (Spain); Quiroga, Sergi [Hospital Vall d' Hebron, Department of Radiology (Spain); Cordoba, Joan [Hospital Vall d' Hebron, Department of Internal Medicine-Hepatology (Spain); Perez, Mercedes; Segarra, Antoni [Hospital Vall d' Hebron, Department of Interventional Radiology (Spain)

2010-10-15

177

Lipoprotein Lp(a). A risk factor for myocardial infarction.  

PubMed

The aim of this study was to test plasma lipoprotein Lp(a) and other lipid and lipoprotein levels for association with the incidence of myocardial infarction. Total plasma cholesterol, triglycerides, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, and Lp(a) were measured in 1486 men at the age of 18 years. In addition, the Broca Index (a measure of relative body weight) and other data were recorded. The sample was divided into probands whose mothers or fathers suffered a myocardial infarction (case group, n = 52) and into probands whose parents had no myocardial infarction (control group, n = 1434). In the case group, 32% had Lp(a) plasma concentrations greater than 25 mg/dl, but only 13.4% of the control group had this level of concentration, a highly significant difference (p less than 0.01). In addition, there was a statistically significant difference in the ratio of LDL cholesterol/HDL cholesterol (p less than 0.05) and the Broca Index (p less than 0.01) between cases and controls. The parents of the case group were significantly older than the parents of the control group; however, when a control group was matched for parents' age, the results were similar. These data suggest that parents of male children with Lp(a) plasma concentrations greater than 25 mg/dl have a 2.5-fold higher incidence of myocardial infarction. Considering the familial aggregation of elevated Lp(a) levels, we conclude that increased levels of this lipoprotein may be a significant risk factor for myocardial infarction. PMID:2969235

Hoefler, G; Harnoncourt, F; Paschke, E; Mirtl, W; Pfeiffer, K H; Kostner, G M

1988-01-01

178

78 FR 14778 - Application to Export Electric Energy; Shell Energy North America (US), L.P.  

Federal Register 2010, 2011, 2012, 2013, 2014

...Shell Energy North America (US), L.P. AGENCY: Office of Electricity Delivery...Shell Energy North America (US), L.P. (Shell Energy) has applied to renew its...Shell Energy North America (US), L.P., 1000 Main, Level 12, Houston, TX...

2013-03-07

179

78 FR 14779 - Application to Export Electric Energy; Shell Energy North America (US), L.P.  

Federal Register 2010, 2011, 2012, 2013, 2014

...Shell Energy North America (US), L.P. AGENCY: Office of Electricity Delivery...Shell Energy North America (US), L.P. (Shell Energy) has applied to renew its...Shell Energy North America (US), L.P., 1000 Main, Level 12, Houston, TX...

2013-03-07

180

Subspaces of Lp Isometric to Subspaces of p F. Delbaen , H. Jarchow (1)  

E-print Network

Subspaces of Lp Isometric to Subspaces of p F. Delbaen , H. Jarchow (1) , A. Pelczy´nski (2) Abstract. We present three results on isometric embeddings of a (closed, linear) subspace X of Lp = Lp[0, 1] into p. First we show that if p / 2N, then X is isometrically isomorphic to a subspace of p if and only

Delbaen, Freddy

181

77 FR 38467 - Special Conditions: Gulfstream Aerospace LP (GALP), Model Gulfstream G280 Airplane; Isolation or...  

Federal Register 2010, 2011, 2012, 2013, 2014

...25-464-SC] Special Conditions: Gulfstream Aerospace LP (GALP), Model Gulfstream G280 Airplane...conditions are issued for the Gulfstream Aerospace LP, Model Gulfstream G280 airplane...Background On March 30, 2006, Gulfstream Aerospace LP (hereafter referred to...

2012-06-28

182

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2012 CFR

... 2012-07-01 false Liquefied petroleum gas (LP-Gas). 1926.153 Section...Prevention § 1926.153 Liquefied petroleum gas (LP-Gas). (a) Approval of...for transportation or storing liquefied petroleum gases. (b) Welding on LP-Gas...

2012-07-01

183

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2014 CFR

... 2014-07-01 false Liquefied petroleum gas (LP-Gas). 1926.153 Section...Prevention § 1926.153 Liquefied petroleum gas (LP-Gas). (a) Approval of...for transportation or storing liquefied petroleum gases. (b) Welding on LP-Gas...

2014-07-01

184

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2010 CFR

... 2010-07-01 false Liquefied petroleum gas (LP-Gas). 1926.153 Section...Prevention § 1926.153 Liquefied petroleum gas (LP-Gas). (a) Approval of...for transportation or storing liquefied petroleum gases. (b) Welding on LP-Gas...

2010-07-01

185

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Liquefied petroleum gas (LP-Gas). 1926.153 Section...Prevention § 1926.153 Liquefied petroleum gas (LP-Gas). (a) Approval of...for transportation or storing liquefied petroleum gases. (b) Welding on LP-Gas...

2013-07-01

186

29 CFR 1926.153 - Liquefied petroleum gas (LP-Gas).  

Code of Federal Regulations, 2011 CFR

... 2011-07-01 false Liquefied petroleum gas (LP-Gas). 1926.153 Section...Prevention § 1926.153 Liquefied petroleum gas (LP-Gas). (a) Approval of...for transportation or storing liquefied petroleum gases. (b) Welding on LP-Gas...

2011-07-01

187

Embolization of splenorenal shunt associated to portal vein thrombosis and hepatic encephalopathy  

PubMed Central

Hepatic encephalopathy (HE) is a cognitive disturbance characterized by neuropsychiatric alterations. It occurs in acute and chronic hepatic disease and also in patients with portosystemic shunts. The presence of these portosystemic shunts allows the passage of nitrogenous substances from the intestines through systemic veins without liver depuration. Therefore, the embolization of these shunts has been performed to control HE manifestations, but the presence of portal vein thrombosis is considered a contraindication. In this presentation we show a cirrhotic patient with severe HE and portal vein thrombosis who was submitted to embolization of a large portosystemic shunt. Case report: a 57 years-old cirrhotic patient who had been hospitalized many times for persistent HE and hepatic coma, even without precipitant factors. She had a wide portosystemic shunt and also portal vein thrombosis. The abdominal angiography confirmed the splenorenal shunt and showed other shunts. The larger shunt was embolized through placement of microcoils, and the patient had no recurrence of overt HE. There was a little increase of esophageal and gastric varices, but no endoscopic treatment was needed. Since portosystemic shunts are frequent causes of recurrent HE in cirrhotic patients, portal vein thrombosis should be considered a relative contraindication to perform a shunt embolization. However, in particular cases with many shunts and severe HE, we found that one of these shunts can be safely embolized and this procedure can be sufficient to obtain a good HE recovery. In conclusion, we reported a case of persistent HE due to a wide portosystemic shunt associated with portal vein thrombosis. As the patient had other shunts, she was successfully treated by embolization of the larger shunt. PMID:25400477

Franzoni, Letícia de Campos; de Carvalho, Fábio Cardoso; Garzon, Rafael Gomes de Almeida; Yamashiro, Fábio da Silva; Augusti, Laís; Santos, Lívia Alves Amaral; Dorna, Mariana de Souza; Baima, Júlio Pinheiro; Lima, Talles Bazeia; Caramori, Carlos Antonio; Silva, Giovanni Faria; Romeiro, Fernando Gomes

2014-01-01

188

Complications and subsequent removal of retained shunt hardware after endoscopic third ventriculostomy: case series.  

PubMed

This case series highlights multiple complications and subsequent removal of retained shunt hardware in pediatric patients after successful endoscopic third ventriculostomy (ETV). Removal or retention of existing shunt hardware following ETV represents an important dilemma. Prior studies have reported infections and organ perforation related to nonfunctioning shunts but none in the context of successful ETV. Data obtained in 3 children with hydrocephalus treated at the authors' institution were retrospectively reviewed after the patients experienced complications due to retained shunt hardware following ETV. Etiologies of hydrocephalus included tectal glioma and intraventricular hemorrhage. All 3 patients had a history of multiple shunt revisions and underwent urgent ETV in the setting of a shunt malfunction. In each case, the entire shunt system was left in situ, but it became the source of subsequent complications. Two of the 3 patients presented with the shunt infected by gram-negative bacilli 10 days and 4.5 months postoperatively, respectively. The remaining patient experienced wound dehiscence over the shunt valve 4.5 months after ETV. In all patients, the complications were managed successfully by removing the shunt hardware. None of the patients required repeat shunt insertion from the time of removal throughout the follow-up period (mean 24 months, range 9-36 months). During the study period, a total of 6 patients with indwelling shunt hardware underwent ETV with the expectation of being shunt independent. Among these 6 patients, 3 experienced no complications from the retained hardware whereas 3 patients (50%) ultimately experienced adverse consequences related to retained hardware. This case series illustrates complications involving retained shunt hardware after successful ETV. These examples support consideration of shunt removal at the time of ETV in the appropriate context. PMID:23560795

Pindrik, Jonathan; Jallo, George I; Ahn, Edward S

2013-06-01

189

Large area shunt defect free GaAs solar cells  

NASA Astrophysics Data System (ADS)

Shunt defects have been found to be the type of defect that can degrade and cause failure in GaAs solar cells. Because of their catastrophic effects, it is necessary to ensure that no shunt defects are formed in the solar cell. A technique for fabricating large-area shunt-defect-free GaAs solar cells has been investigated. A Be-doped GaAlAs window layer was grown directly on an n-type GaAs substrate by isothermal liquid-phase epitaxial growth (ILPE). By growing directly on the GaAs substrate and not growing the usual buffer, absorber, collector, and window layer combination, the fabrication is simplified and yields can be large. It was found that Be from the liquid GaAlAs melt diffused into the GaAs to form a complete collector layer. Because the collector is complete, a shunt-defect-free solar cell is produced. The results of the ILPE growth are reported for both 5.1-sq cm and 0.12-sq cm solar cells. The technique is very versatile and may be used to fabricate larger-area solar cells.

Kilmer, Louis C.; Barnett, Allen M.

190

Optimization of electric shunt resonant circuits for electroacoustic absorbers  

E-print Network

Optimization of electric shunt resonant circuits for electroacoustic absorbers H. Lissek, R issue is to properly design an electrical matching circuit which, when connected across the transducer as an absorber/reflector of sound, and the electric terminals of which are connected to a dedicated electric load

Paris-Sud XI, Université de

191

CONTROL ORIENTATED SYNTHESIS OF ELECTROMAGNETIC SHUNT IMPEDANCES FOR  

E-print Network

an electromagnetic transducer is used as an actuator. Electromagnetic transducers can be used as sensorsCONTROL ORIENTATED SYNTHESIS OF ELECTROMAGNETIC SHUNT IMPEDANCES FOR VIBRATION ISOLATION 1 S an electromagnetic transducer to develop the required control forces. In this paper, the technique of sensor

Fleming, Andrew J.

192

Congenital multiple intrahepatic portosystemic shunt: an autopsy case.  

PubMed

Multiple intrahepatic portosystemic shunt (IPSS) without portal hypertension, now thought to be congenital in origin, is very rare. The presence of IPSS, unlike other congenital diseases, may not be recognized for several decades due to the time it takes to develop hepatic encephalopathy. In this article, we report an autopsy case of an 80-year-old Japanese woman with a one-month history of hyperammonemic encephalopathy. Radiological examination of the liver revealed some abnormal connections between the branches of the portal veins and the hepatic veins, but the cause of the aberrant blood flow was not found. The cause of death was extensive cerebral infarction due to thromboembolism. At postmortem examination, multiple anomalous blood vessels were identified histologically in both lobes of the non-cirrhotic liver. In comparison with the few similar cases existing in the literature, this case should be diagnosed as congenital IPSS. To our knowledge, this is the first detailed histological study of IPSS, as several autopsy case reports exist but their histological descriptions are poor. Unlike past reports, the shunt vessels were accompanied by clear elastic lamellae that were microscopically observed. In addition to shunt vessels, septal fibrosis, disorder of hepatic acinar structure, and sinusoidal dilatation and capillarization were observed in the liver. We suggest that these histological modifications observed in the circumference of the shunt vessels acted as secondary regenerative/hyperplastic changes based on blood-flow imbalance caused by the IPSS. PMID:24427367

Takahashi, Seishiro; Yoshida, Eriko; Sakanishi, Yasushi; Tohyama, Norihiro; Ayhan, Ayse; Ogawa, Hiroshi

2014-01-01

193

Predicting shunt currents in stacks of bipolar plate cells  

Microsoft Academic Search

A method is presented for predicting shunt currents in stacks of undivided and divided bipolar plate cells. The method is an efficient way of solving the coupled sets of algebraic equations that arise from using circuit analog models to represent the current paths in stacks of undivided or divided bipolar plate cells. These algebraic equations can be either linear or

R. E. White; C. W. Walton; H. S. Burney; R. N. Beaver

1986-01-01

194

Noninvasive evaluation of portal-systemic shunting by glyceryl trinitrate.  

PubMed

Portal-systemic shunting is an important circulatory abnormality in patients with liver cirrhosis. Glyceryl trinitrate (GTN) that is normally subject to first pass elimination, may exhibit higher bioavailability in these patients. This study compares the pharmacodynamic effects of GTN after peroral and sublingual administration for noninvasive assessment of shunting. Six control subjects and 15 patients with cirrhosis were studied after oral and sublingual application of 0.5 mg of GTN. Liver cirrhosis was complicated by portal hypertension in 7 of the patients and 4 patients had surgically implanted portocaval anastomosis. Digital plethysmography, which is highly sensitive and is essentially noninvasive in nature, was used to assess and compare the pharmacodynamic effects of GTN. The following values of the ratio of areas under the pharmacodynamic effects/time curve were obtained: 0.08 +/- 0.06 in healthy subjects, 0.52 +/- 0.21 in patients with uncomplicated cirrhosis, 0.99 +/- 0.34 in patients with portal hypertension and 1.24 +/- 0.43 in patients with portal-systemic shunts. We conclude that increased bioavailability of GTN reflects portal-systemic shunting and might be used providing that the pharmacodynamic data reflect both pharmacokinetic variability and the pharmacokinetic-pharmacodynamic interrelations. PMID:12449441

Slanar, O; Aubrecht, J; Perlík, F

2002-01-01

195

Clinical results of fetal obstructive uropathy treated by vesicoamniotic shunting  

Microsoft Academic Search

Objectives. To report the clinical results of 5 fetuses after a vesicoamniotic shunting procedure (VASP).Methods. Between 1995 and 1998, 5 patients (two with prune belly syndrome, one with a cloacal anomaly, one with urethral stenosis, and one with a sacrococcygeal teratoma) underwent VASP using a double-basket catheter. We used the following selection criteria: a fetus without chromosomal defects, with oligohydramnios,

Yasuo Makino; Hideki Kobayashi; Kazuo Kyono; Kazuhiro Oshima; Tatsuhiko Kawarabayashi

2000-01-01

196

Intrahepatic portosystemic venous shunt associated with biliary atresia: case report.  

PubMed

We describe an infant with intrahepatic portosystemic venous shunt (IPSVS), which was detected by MR angiography. IPSVS is rare and its cause is disputed. However, with improvements in imaging the number of reports of IPSVS identified incidentally in patients without definite symptoms is increasing. The present case is the first associated with congenital biliary atresia and the youngest reported in the literature. PMID:10929369

Yamagami, T; Nakamura, T; Tokiwa, K; Ohno, K; Itoh, H; Maeda, T

2000-07-01

197

A Gender Recognition System using Shunting Inhibitory Convolutional Neural Networks  

Microsoft Academic Search

In this paper, we employ shunting inhibitory convolutional neural networks to develop an automatic gender recognition system. The system comprises two modules: a face detector and a gender classifier. The human faces are first detected and localized in the input image. Each detected face is then passed to the gender classifier to determine whether it is a male or female.

Fok Hing Chi Tivive; Abdesselam Bouzerdoum

2006-01-01

198

The Application of Controlled Intracranial Hypertension in Slit Ventricle Syndrome Patients with Obstructive Hydrocephalus and Shunt Malfunction  

Microsoft Academic Search

When a shunted patient with slit-ventricle syndrome (SVS) presents with a shunt malfunction or infection, the third ventricle may not be of sufficient caliber, despite the shunt malfunction, to allow atraumatic passage of an endoscope to the floor of the third ventricle. We describe four slit ventricle syndrome patients with respectively 24, 12, 18 and 2 prior shunt revisions who

William E. Butler; Saad A. Khan

2001-01-01

199

Is percutaneous endoscopic gastrostomy tube placement safe in patients with ventriculoperitoneal shunts?  

PubMed Central

AIM: To investigate whether percutaneous endoscopic gastrostomy (PEG) tube placement is safe in patients with ventriculoperitoneal (VP) shunts. METHODS: This was a retrospective study of all patients undergoing PEG insertion at our institution between June 1999 and June 2006. Post-PEG complications were compared between two groups according to the presence or absence of VP shunts. VP shunt infection rates, the interval between PEG placement and VP shunt catheter insertion, and long-term follow-up were also investigated. RESULTS: Fifty-five patients qualified for the study. Seven patients (12.7%) had pre-existing VP shunts. All patients received prophylactic antibiotics. The complication rate did not differ between VP shunt patients undergoing PEG (PEG/VP group) and non-VP shunt patients undergoing PEG (control group) [1 (14.3%) vs 6 (12.5%), P = 1.000]. All patients in the PEG/VP group had undergone VP shunt insertion prior to PEG placement. The mean interval between VP shunt insertion and PEG placement was 308.7 d (range, 65-831 d). The mean follow-up duration in the PEG/VP group was 6.4 mo (range, 1-15 mo). There were no VP shunt infections, although one patient in the PEG/VP group developed a minor peristomal infection during follow-up. CONCLUSION: Complications following PEG placement in patients with VP shunts were infrequent in this study. PMID:19575495

Kim, Jin-Soo; Park, Yong-Wan; Kim, Hyung-Keun; Cho, Young-Seok; Kim, Sung-Soo; Youn, Na-Ri; Chae, Hiun-Suk

2009-01-01

200

Risk factors for pediatric ventriculoperitoneal shunt infection and predictors of infectious pathogens.  

PubMed

Identification of risk factors for shunt infection and predictors of infectious pathogens may improve current methods to prevent and treat shunt infections. We reviewed data on 820 consecutive ventriculoperitoneal (VP) shunt placement procedures in 442 pediatric patients at our institution during 1992-1998. Ninety-two shunts (11%) developed infection a median of 19 days (interquartile range, 11-35 days) after insertion. Premature birth (relative risk [RR], 4.81; 95% confidence interval [CI], 2.19-10.87), previous shunt infection (RR, 3.83; 95% CI, 2.40-6.13), and intraoperative use of the neuroendoscope (RR, 1.58; 95% CI, 1.01-2.50) were independent risk factors for shunt infection. The bacterial organisms early after shunt surgery (<14 days) were the same as those late after shunt surgery (>14 days). As determined by an analysis of the 92 infected shunts, hospital stay of >3 days at the time of shunt insertion (odds ratio [OR], 5.27; 95% CI, 1.15-25.3) and prior Staphylococcus aureus shunt infection (OR, 5.91; 95% CI, 1.35-25.9) independently increased the odds that S. aureus was the causal pathogen. PMID:12652386

McGirt, Matthew J; Zaas, Aimee; Fuchs, Herbert E; George, Timothy M; Kaye, Keith; Sexton, Daniel J

2003-04-01

201

Management of surgical splenorenal shunt-related hepatic myelopathy with endovascular interventional techniques.  

PubMed

We present a case with hepatic myelopathy (HM) due to a surgical splenorenal shunt that was successfully treated by endovascular interventional techniques. A 39-year-old man presented with progressive spastic paraparesis of his lower limbs 14 mo after a splenorenal shunt. A portal venogram identified a widened patent splenorenal shunt. We used an occlusion balloon catheter initially to occlude the shunt. Further monitoring of the patient revealed a decrease in his serum ammonia level and an improvement in leg strength. We then used an Amplatzer vascular plug (AVP) to enable closure of the shunt. During the follow up period of 7 mo, the patient experienced significant clinical improvement and normalization of blood ammonia, without any complications. Occlusion of a surgically created splenorenal shunt with AVP represents an alternative therapy to surgery or coil embolization that can help to relieve shunt-induced HM symptoms. PMID:23323015

Wang, Mao-Qiang; Liu, Feng-Yong; Duan, Feng

2012-12-21

202

Use of magnetic resonance angiography for diagnosis of portosystemic shunts in dogs.  

PubMed

A prospective study was conducted to determine the sensitivity and specificity of diagnosis of portosystemic shunts (PSS) and the accuracy of anatomically locating single congenital PSS in dogs using magnetic resonance angiography (MRA). MRA was performed on 10 normal dogs and 23 dogs with PSS. Sensitivity and specificity of MRA to diagnose any shunt among all dogs were 80% and 100%, respectively. Among dogs identified with PSS, sensitivity and specificity of MRA for diagnosis of multiple extrahepatic shunts were 63% and 97%, respectively, and for diagnosis of single congenital shunts were 79% and 100%, respectively. Using MRA, radiologists correctly identified shunts as extrahepatic or intrahepatic in 83% of patients and correctly identified the origin and insertion of the shunts in 57% and 97% of patients, respectively. Use of MRA is specific for diagnosis of PSS and is a sensitive indicator of anatomic location of single congenital portosystemic shunts. PMID:10519303

Seguin, B; Tobias, K M; Gavin, P R; Tucker, R L

1999-01-01

203

The Sophy valve and the el-Shafei shunt system for adult hydrocephalus.  

PubMed Central

A selected series of 22 adult patients with hydrocephalus were treated by a shunt system incorporating a variable pressure Sophy valve or by ventriculojugular shunting against the direction of blood flow using the El-Shafei system. One patient had insertion of two Sophy valves and an El-Shafei shunt. Patient selection was reserved to those with hydrocephalus thought to be at high risk when shunted with systems containing a conventional unipressure valve. None of the eight patients who had ventriculojugular shunting by the El-Shafei method demonstrated any notable clinical or radiological improvement subsequent to shunt insertion. Of the 16 Sophy devices inserted only seven produced a satisfactory result. The current evaluation of shunt malfunction could be improved by support for a national register. PMID:7500101

O'Reilly, G; Williams, B

1995-01-01

204

Shunt implantations and peritoneal catheters: Do not cut beyond 20 cm  

PubMed Central

Background: Ventriculoperitoneal shunts are supplied with long peritoneal catheters, most commonly between 80 and 120 cm long. ISO/DIS 7197/2006[15] shunt manufacturing procedures include peritoneal catheter as an integrate of the total resistance. Cutting pieces of peritoneal catheters upon shunt implantation or revision is a common procedure. Methods: We evaluated five shunts assembled with different total pressure resistances and variable peritoneal catheter lengths in order to clarify the changes that occurred in the hydrodynamic profile when peritoneal catheters were cut upon shunt implantation or shunt revision. Results: Originally, all shunts performed within the operational range. Shunt 1 performed in a lower pressure range at 200 mm cut off peritoneal catheter and as a low-pressure shunt with –300 mm cut off. Shunt 2 was manufactured to run at the higher border pressure range, and it went out of specification with a 300 mm cut off. Shunt 3 was manufactured to run close to the lower border pressure range, and at 100 mm cutoff, it was already borderline in a lower resistive category. Other shunts also responded similarly. Conclusion: The limit to maintain a shunt in its original pressure settings was 20 cm peritoneal catheter cutting length. By cutting longer pieces of peritoneal catheter, one would submit patients to a less-resistive regimen than intended and his reasoning will be compromised. The pediatric population is more prone to suffer from the consequences of cutting catheters. Shunt manufacturers should consider adopting peritoneal catheters according to the age (height) of the patient. PMID:25250184

Maset, Angelo Luiz; Suriano, ?talo Capraro; Monteiro, Ruy; Pinto, José Ricardo Camilo; de Andrade, José Ricardo; Mancini, Bruna Monieli; Ramin, Sérgio Luiz; Moraes, Dionei Freitas; Cavalheiro, Sérgio

2014-01-01

205

Kinematic analysis following implantation of the PRESTIGE LP  

PubMed Central

Background The clinical success of cervical arthroplasty hinges on the ability to preserve or improve the biomechanics of the functional spinal unit. The purpose of this study was to conduct a radiologic assessment of kinematic parameters preimplantation and postimplantation of the PRESTIGE LP Cervical Disc System (Medtronic, Memphis, Tennessee). Methods A total of 120 radiographs of 20 patients following single-level implantation of the PRESTIGE LP were retrospectively reviewed. Static and dynamic radiologic assessments were performed before surgery and at 1 year postoperation. Kinematic parameters including range of motion (ROM), horizontal translation, center of rotation (COR X, Y), anterior disc height and posterior disc height, and disc angle and shell angle were assessed for each spinal level using quantitative motion analysis software. Clinical outcomes were assessed using the short form health survey physical component scores and mental component scores. Results The mean physical component scores and mental component scores of the short form health survey (SF-36) improved significantly following surgery. At 1 year postoperation, ROM, translation, and COR X were preserved. The COR Y shifted superiorly from 3.17 ± 2.08 mm preoperation to 0.98 ± 2.23 mm postoperation (P < .001). The anterior disc height and posterior disc height were significantly increased following surgery (3.97 ± 1.01 to 4.78 ± 1.11 mm and 3.04 ± 0.69 to 3.66 ± 0.61 mm, respectively; P < .01). The preoperative disc angle was 3.32° ± 2.92° and the postoperative shell angle was 1.11° ± 4.29°, with a mean change of ?2.22° ± 4.63° (P < .05). Conclusions The PRESTIGE LP maintained preoperative ROM, translation, and COR X values. The postoperative COR Y value changed significantly by shifting superiorly, accompanied by an increase in DH. There was a loss of lordosis at the level of surgery, with the PRESTIGE LP endplates having an almost parallel endplate configuration.

Kowalczyk, Izabela; Chaudhary, Navjot; Duggal, Neil

2013-01-01

206

Autoregressive model in the Lp norm space for EEG analysis.  

PubMed

The autoregressive (AR) model is widely used in electroencephalogram (EEG) analyses such as waveform fitting, spectrum estimation, and system identification. In real applications, EEGs are inevitably contaminated with unexpected outlier artifacts, and this must be overcome. However, most of the current AR models are based on the L2 norm structure, which exaggerates the outlier effect due to the square property of the L2 norm. In this paper, a novel AR object function is constructed in the Lp (p?1) norm space with the aim to compress the outlier effects on EEG analysis, and a fast iteration procedure is developed to solve this new AR model. The quantitative evaluation using simulated EEGs with outliers proves that the proposed Lp (p?1) AR can estimate the AR parameters more robustly than the Yule-Walker, Burg and LS methods, under various simulated outlier conditions. The actual application to the resting EEG recording with ocular artifacts also demonstrates that Lp (p?1) AR can effectively address the outliers and recover a resting EEG power spectrum that is more consistent with its physiological basis. PMID:25448380

Li, Peiyang; Wang, Xurui; Li, Fali; Zhang, Rui; Ma, Teng; Peng, Yueheng; Lei, Xu; Tian, Yin; Guo, Daqing; Liu, Tiejun; Yao, Dezhong; Xu, Peng

2015-01-30

207

The orbital volume measurement in patients with ventriculoperitoneal shunt.  

PubMed

Enophthalmos occurs from the increased bony volume or decreased soft tissue volume in the orbit and can be caused in patients with long-term ventriculoperitoneal (VP) shunt. This study tried to find out the change of orbital volume by measuring the orbital volume before and after operation in adult patients who underwent VP shunt for hydrocephalus. The 2 evaluators measured orbital volume by using ITK-SNAP 2.4 program with double-blind test for computed tomography images before and after operation targeting 36 patients over the age of 18 who underwent VP shunt with pressure-controlled valve from 2003 to 2011. Wilcoxon matched-pairs signed-rank test of GraphPad software was used to statistically analyze the difference in orbital volume change before and after operation. In case of mean pre-op orbital volume of total 36 patients, the right was measured as 23.72 ± 4.65 cm, the left as 23.47 ± 4.61 cm, the post-op right as 24.67 ± 4.70 cm, and the left as 24.18 ± 4.63 cm, showing no statistically significant difference (P = 0.106). The mean pre-op orbital volume of 14 people (28 eyes) followed for more than 11 months was 25.06 ± 4.58 cm in the right and 24.4 ± 5.02 cm in the left and the mean post-op orbital volume was 27.0 ± 4.28 cm in the right and 25.76 ± 3.92 cm in the left, showing statistically significant differences in the change of the volume before and after shunt operation (P = 0.0057). In patients who maintain long-term shunt devices after VP shunt, remodeling of matured orbital bone may be caused due to the change in pressure gradient between cranial cavity and orbit and the possible occurrence of resulting secondary enophthalmos by increased orbital volume should be considered. PMID:25490570

Kim, Jong-Min; Chang, Moo-Hwan; Kyung, Sungeun E

2015-01-01

208

Neurodevelopmental Outcome of Extremely Low Birth Weight Infants With Posthemorrhagic Hydrocephalus Requiring Shunt Insertion  

PubMed Central

OBJECTIVE We aimed to evaluate neurodevelopmental and growth outcomes among extremely low birth weight infants who had severe intraventricular hemorrhage that required shunt insertion compared with infants without shunt insertion. METHODS Infants who were born in 1993–2002 with birth weights of 401 to 1000 g were enrolled in a very low birth weight registry at medical centers that participate in the National Institute of Child Health and Human Development Neonatal Research Network, and returned for follow-up at 18 to 22 months’ corrected age were studied. Eighty-two percent of survivors completed follow-up, and 6161 children were classified into 5 groups: group 1, no intraventricular hemorrhage/no shunt (n = 5163); group 2, intraventricular hemorrhage grade 3/no shunt (n = 459); group 3, intraventricular hemorrhage grade 3/shunt (n = 103); group 4, intraventricular hemorrhage grade 4/no shunt (n = 311); and group 5, intraventricular hemorrhage grade 4/shunt (n = 125). Group comparisons were evaluated with ?2 and Wilcoxon tests, and regression models were used to compare outcomes after adjustment for covariates. RESULTS Children with severe intraventricular hemorrhage and shunts had significantly lower scores on the Bayley Scales of Infant Development IIR compared with children with no intraventricular hemorrhage and with children with intraventricular hemorrhage of the same grade and no shunt. Infants with shunts were at increased risk for cerebral palsy and head circumference at the <10th percentile at 18 months’ adjusted age. Greatest differences were observed between children with shunts and those with no intraventricular hemorrhage on these outcomes. CONCLUSIONS This large cohort study suggests that extremely low birth weight children with severe intraventricular hemorrhage that requires shunt insertion are at greatest risk for adverse neurodevelopmental and growth outcomes at 18 to 22 months compared with children with and without severe intraventricular hemorrhage and with no shunt. Long-term follow-up is needed to determine whether adverse outcomes persist or improve over time. PMID:18390958

Adams-Chapman, Ira; Hansen, Nellie I.; Stoll, Barbara J.; Higgins, Rose

2009-01-01

209

Successful treatment of pulmonary hypertension secondary to congenital extrahepatic portocaval shunts (Abernethy type 2) by living donor liver transplantation after surgical shunt ligation.  

PubMed

In this report, we describe a living donor liver transplantation (LDLT) in a patient (7-year-old boy) with Abernethy type 2 congenital extrahepatic portocaval shunts (CEPS). This patient underwent a surgical shunt ligation as the first treatment for pulmonary hypertension; pulmonary hypertension was improved and controlled successfully 4 years after the first operation. However, pulmonary hypertension recurred gradually because of multiple intrahepatic portosystemic shunts; therefore, LDLT was performed as a radical treatment of intrahepatic portosystemic shunts. His pulmonary arterial pressure was also controlled 22 months after LDLT, the postoperative continuous intravenous prostaglandin I(2) (PGI(2)) treatment could be withdrawn successfully. We suggest that clinicians carefully follow up the recurrent portosystemic shunt and cardiopulmonary disorders secondary to Abernethy type 2 CEPS. PMID:19761556

Iida, Taku; Ogura, Yasuhiro; Doi, Hiraku; Yagi, Shintaro; Kanazawa, Hiroyuki; Imai, Hisashi; Sakamoto, Seisuke; Okamoto, Shinya; Uemoto, Shinji

2010-01-01

210

Unilateral shunt formation with thoracic aortic dissection in a whippet.  

PubMed

A three-year-old neutered male whippet was presented with intermittent, exercise-induced paraparesis. Femoral pulses were bilaterally absent. Neurologic examination was suggestive of a thoracolumbar myelopathy. Blood pressure measurements revealed hypotension in both pelvic limbs, hypertension in the right thoracic limb and it was immeasurable in the left thoracic limb. Echocardiography was within reference limits. A clear vascular pulsation was palpable on the right ventral abdominal wall. Computed tomographic angiography revealed a dissection of the aortic wall between the left subclavian artery and the brachiocephalic trunk with subsequent thrombus formation. A shunt between the right internal thoracic, cranial and caudal epigastric arteries to preserve blood flow to the pelvic limbs was visualized. Necropsy was declined by the owner. This is the first case report describing the formation of a unilateral vascular shunt following a thoracic aortic occlusion, which presented as exercise-induced paraparesis. PMID:24602076

Cornelis, I; Bosmans, T; Doom, M; Binst, D; Van der Vekens, E; Kromhout, K; Cornillie, P; Van Ham, L

2014-06-01

211

Magnetically programmable shunt valve: MRI at 3-Tesla.  

PubMed

A magnetically programmable cerebrospinal fluid (CSF) shunt valve (Codman Hakim Programmable Valve, Codman, a Johnson & Johnson Company, Raynham, MA) was assessed for magnetic field interactions, heating, artifacts and functional changes at 3-Tesla. The programmable valve showed minor magnetic field interactions and heating (+0.4 degrees C). Artifacts were relatively large in relation to the size and shape of this implant and, as such, may create a problem if the area of interest is in proximity to this implant. While multiple exposures and various magnetic resonance imaging (MRI) conditions at 3-Tesla changed the settings of some valves (i.e., reprogramming was needed), the function of the programmable valve was not permanently affected. Therefore, this magnetically programmable CSF shunt valve is acceptable for a patient undergoing MRI at 3-Tesla or less when specific safety guidelines are followed, including resetting the valve, as needed. PMID:17707175

Shellock, Frank G; Wilson, Stephen F; Mauge, Christophe P

2007-09-01

212

Failure of a Torkildsen shunt after functioning for 50 years.  

PubMed

Mechanical obstruction is a severe complication of ventricular catheter use. Its incidence was shown to be high in the 1960s and 1970s, with up to 41% of the catheters becoming obstructed within 10 years after surgery. The authors present what is to their knowledge the first reported case of a patient with failure of a Torkildsen shunt after 50 years of functioning. A 60-year-old woman presented with increasing gait ataxia, decline in cognitive functions (including short-term memory loss), and slight urinary incontinence. The diagnosis of hydrocephalus and thus malfunction of the Torkildsen shunt implanted 50 years previously was confirmed by MR images, which revealed a prominent triventricular hydrocephalus. The patient subsequently underwent endoscopic third ventriculostomy (ETV), the current surgical treatment of choice, resulting in total resolution of her neurological symptoms and amelioration of cerebral tissue distension. Decrease in ventricle dilation and success of the ETV were confirmed on postoperative follow-up MR images. PMID:19715420

Zinn, Pascal O; Bozinov, Oliver; Burkhardt, Jan-Karl; Reisch, Robert; Ya?argil, M Gazi; Bertalanffy, Helmut

2010-04-01

213

Ventriculoperitoneal shunt for hydrocephalus caused by central nervous system metastasis  

Microsoft Academic Search

The development of better diagnostic tools and therapeutic modalities has increased the incidence of central nervous system\\u000a (CNS) metastasis in malignant tumor patients. Hydrocephalus can result from CNS metastasis and frustrate cancer treatment.\\u000a The authors sought to investigate the outcomes and the roles of ventriculoperitoneal shunts (VPS) in patients with CNS metastasis.\\u000a The medical records of 50 consecutive patients who

Seung Hoon Lee; Doo Sik Kong; Ho Joon Seol; Do-Hyun Nam; Jung-Il Lee

214

Congenital Portosystemic Shunts and AMPLATZER Vascular Plug Occlusion in Newborns  

Microsoft Academic Search

Congenital portosystemic shunts (CPSs) may cause myriad manifestations. They can be detected prenatally, in infancy, or later.\\u000a They may involute, cause acute symptoms, or remain unrecognized and cause chronic disease. As CPSs can require treatment,\\u000a early diagnosis allows close monitoring. In symptomatic patients, interventional catheterization embolization of CPSs can\\u000a be undertaken at any age.

William N. Evans; Alvaro Galindo; Ruben J. Acherman; Abraham Rothman; Dean P. Berthoty

2009-01-01

215

High Isolation CPW MEMS Shunt Switches Part 1: Modeling  

Microsoft Academic Search

This paper, the first of two parts, presents an electromagnetic model for membrane CPW MEMS shunt switches for microwave\\/mm-wave applications. The up- state capacitance can be accurately modeled using 3-D static solvers, and full-wave solvers are used to predict the current distribution and the inductance of the switch. The loss in the up-state position is equivalent to the CPW line

Jeremy B. Muldavin; Gabriel M. Rebeiz

1999-01-01

216

High-isolation CPW MEMS shunt switches. 1. Modeling  

Microsoft Academic Search

This paper, the first of two parts, presents an electromagnetic model for membrane microelectromechanical systems (MEMS) shunt switches for microwave\\/millimeter-wave applications. The up-state capacitance can be accurately modeled using three-dimensional static solvers, and full-wave solvers are used to predict the current distribution and inductance of the switch. The loss in the up-state position is equivalent to the coplanar waveguide line

Jeremy B. Muldavin; Gabriel M. Rebeiz

2000-01-01

217

A review of fetal thoracoamniotic & vesicoamniotic shunt procedures.  

PubMed

Fetal anomalies such as lower urinary tract obstructions and fluid-filled space-occupying lesions in the fetal chest can result in severe morbidity or mortality if left untreated. In-utero fetal shunt placement offers the potential to improve outcomes in infants with these conditions. The role of the nurse is paramount in the clinical and psychosocial management of the mother and family. PMID:22502723

Gregory, Casey L; Wright, Jane; Schwarz, Jessica; Rakowski, Laura

2012-01-01

218

Net cardiac shunts in anuran amphibians: physiology or physics?  

PubMed

Amphibians have a single ventricle and common conus arteriosus that produces an equal pressure to the parallel pulmocutaneous and systemic vascular circuits. The distribution of blood flows between the pulmocutaneous (Qpul) and systemic (Qsys) circuits (net cardiac shunt) varies with a number of environmental conditions and behaviours; although autonomic regulation of pulmonary vascular resistance conductance has been emphasized, little attention has been paid to the possible contribution of the passive physical characteristics of the two circuits to pressure changes associated with variation in cardiac output. In this study, we re-analysed three recent studies that recorded net cardiac shunts in the cane toad (Rhinella marina) under a variety of conditions and treatments. In all three studies, Qpul and Qsys were linearly related to cardiac output (Qtot), but the slope was threefold higher for Qpul compared with Qsys as predicted by relative conductance increases associated with increases in pressure from perfused preparations where autonomic regulation and humoral control were eliminated. Our analysis indicates that the net cardiac shunt in the cane toad is predicted primarily by the physical, rather than physiological, characteristics of the parallel pulmonary and systemic vascular circuits. PMID:24902743

Hillman, Stanley S; Hedrick, Michael S; Kohl, Zachary F

2014-08-15

219

Nosocomial meningitis in children after ventriculoperitoneal shunt insertion.  

PubMed

This study reviews 33 cases of ventriculoperitoneal shunt (VPS) meningitis among 415 children after 540 shunt insertions within 8 y, in 9 paediatric intensive care units from 5 centres in Slovakia. The incidence of VPS meningitis was 6.3% per insertion. The most common organisms isolated from cerebrospinal fluid (CSF) and shunt were coagulase-negative staphylococci (52.8%), followed by Staphylococcus aureus (13.1%) and Pseudomonas aeruginosa (7.5%). Seven of 15 assessed risk factors were significantly associated with VPS meningitis, compared with non-VPS meningitis: prior meningitis with hydrocephalus (15.1 vs 1.5%, p < 0.015), perinatal pathology (51.1 vs 1.5%, p < 0.001), very low birthweight (66.6 vs 16.2%, p < 0.001), polymicrobial nosocomial meningitis (30.3 vs 5.9%, p < 0.002), S. aureus (21.2 vs 7.3%, p < 0.05), coagulase-negative staphylococci (84.8 vs 30.9%, p < 0.001) and P. aeruginosa and Acinetobacter calcoaceticus (30.3 vs 4.5%, p < 0.001) in aetiology. PMID:10426184

Filka, J; Huttova, M; Tuharsky, J; Sagat, T; Kralinsky, K; Krcmery, V

1999-05-01

220

Chemoembolic Hepatopulmonary Shunt Reduction to Allow Safe Yttrium-90 Radioembolization Lobectomy of Hepatocellular Carcinoma  

SciTech Connect

Yttrium-90 ({sup 90}Y) radioembolization represents an emerging transcatheter treatment option for the management of hepatocellular carcinoma (HCC). Elevation of the hepatopulmonary shunt fraction risks nontarget radiation to the lungs and may limit the use of {sup 90}Y therapy in patients with locally advanced disease with vascular invasion, who often demonstrate increased shunting. We present two cases in which patients with HCC and portal vein invasion resulting in elevated hepatopulmonary shunt fractions underwent chemoembolic shunt closure to allow safe {sup 90}Y radioembolization. Both patients demonstrated excellent tumor response and patient survival. On this basis, we propose a role for chemoembolic reduction of the lung shunt fraction before {sup 90}Y radioembolization in patients with extensive tumor-related hepatopulmonary shunting.

Gaba, Ron C., E-mail: rgaba@uic.edu [University of Illinois Medical Center at Chicago, Department of Radiology, Section in Interventional Radiology (United States); VanMiddlesworth, Kyle A. [Midwestern University School of Medicine (United States)

2012-12-15

221

Role of protein content in CSF ascites following ventriculoperitoneal shunting. Case report.  

PubMed

The case is reported of an 11-year-old girl with a recurrent craniopharyngioma who developed massive ascites following a ventriculoperitoneal (VP) shunt procedure for hydrocephalus, associated with an elevated cerebrospinal fluid (CSF) protein level. The ascites resolved after removal of the shunt. The CSF protein returned to normal levels following excision of the recurrent craniopharyngioma, and ascites did not recur after a second VP shunt was inserted for recurrent hydrocephalus. In this case, elevated CSF protein is believed to have been responsible for ascites developing after VP shunting. There was no recurrence of ascites after the peritoneal cavity was again used for shunting, at which time the protein had returned to normal values. Twelve previous cases of ascites complicating VP shunting are reviewed and the etiology of the condition is discussed. PMID:7097343

Adegbite, A B; Khan, M

1982-09-01

222

Interaction of Epstein-Barr Virus Nuclear Antigen Leader Protein (EBNA-LP) with HS1-Associated Protein X-1: Implication of Cytoplasmic Function of EBNA-LP  

PubMed Central

Epstein-Barr virus (EBV) nuclear antigen leader protein (EBNA-LP) consists of W1W2 repeats and a unique C-terminal Y1Y2 domain and has been suggested to play an important role in EBV-induced transformation. To identify the cellular factors interacting with EBNA-LP, we performed a yeast two-hybrid screen, using EBNA-LP cDNA containing four W1W2 repeats as bait and an EBV-transformed human peripheral blood lymphocyte cDNA library as the source of cellular genes. Our results were as follows. (i) All three cDNAs in positive yeast colonies were found to encode the same cellular protein, HS1-associated protein X-1 (HAX-1), which is localized mainly in the cytoplasm and has been suggested to be involved in the regulation of B-cell signal transduction and apoptosis. (ii) Mutational analysis of EBNA-LP revealed that the association with HAX-1 is mediated by the W1W2 repeat domain. (iii) A purified chimeric protein consisting of glutathione S-transferase fused to EBNA-LP specifically formed complexes with HAX-1 transiently expressed in COS-7 cells. (iv) When EBNA-LP and HAX-1 were coexpressed in COS-7 cells, EBNA-LP was specifically coimmunoprecipitated with HAX-1. (v) Careful cell fractionation experiments of an EBV-infected lymphoblastoid cell line revealed that EBNA-LP is localized in the cytoplasm as well as in the nucleus. (vi) When EBNA-LP containing four W1W2 repeats was expressed in COS-7 cells, EBNA-LP was detected mainly in the nucleus by immunofluorescence assay. Interestingly, when EBNA-LP containing a single W1W2 repeat was expressed in COS-7 cells, EBNA-LP was localized predominantly in the cytoplasm and was colocalized with HAX-1. These results indicate that EBNA-LP is in fact present and may have a significant function in the cytoplasm, possibly by interacting with and affecting the function of HAX-1. PMID:11024139

Kawaguchi, Yasushi; Nakajima, Kaori; Igarashi, Mie; Morita, Tomoko; Tanaka, Michiko; Suzuki, Mikiko; Yokoyama, Akihiko; Matsuda, Go; Kato, Kentaro; Kanamori, Mikiko; Hirai, Kanji

2000-01-01

223

Long-term results of mesocaval shunts with polytetrafluoroethylene grafts.  

PubMed

Despite the introduction of new procedures such as pharmacologic reduction of portal pressure and endoscopic sclerotherapy, the role of surgery in portal hypertension must be reconsidered. The aim of this retrospective study was to evaluate the long-term results of mesocaval interposition shunting in the treatment of recurrent variceal bleeding after sclerotherapy failure or in patients with intractable ascites in whom optimal medical treatments failed. Over a 20-year period, 85 patients (66 men and 19 women; mean age, 53.96 +/- 11.57 years) underwent a mesocaval interposition shunt procedure. Sixty-six patients had recurrent variceal bleeding, and 19 patients had refractory ascites. The underlying etiology of portal hypertension was alcoholic cirrhosis (n = 69), posthepatitis cirrhosis (n = 10), cryptogenic cirrhosis (n = 3), primary biliary cirrhosis (n = 2), and Budd-Chiari syndrome (n = 1). Thirty-one patients were in Child-Pugh grade A, 34 were in grade B, and 20 were in grade C. The mean diameter of the graft was 11.85 +/- 1.53 mm (range, 10-14 mm). Overall, in-hospital mortality was 10.5% (9 of 85 patients). There were 3 postoperative recurrences of variceal hemorrhage and 5 recurrent bleeds during the follow-up. The overall incidence of shunt thrombosis of this series was 10.5%. The total incidence of encephalopathy was 10.5%. Intraoperative gradient pressure measurements before and after shunt showed satisfactory pressure reduction (16.90 +/- 5.32 to 5.12 +/- 2.50/ mmHg; P < 0.0001). The mean follow-up period was 26.09 +/- 25.3 (range, 1-90) months. Nine patients (10.5%) later received liver transplants, with time intervals ranging from 2 months to 5 years. The actuarial survival rate was 92% at 1 year and 75% at 5 years. In our series, the interposition mesocaval shunt seems to be an effective procedure for the control of complications of portal hypertension in cirrhotic patients with good long-term results. Moreover, the procedure can be considered as a solution of choice in patients who are current liver transplant candidates, leaving the hepatic hilus intact. PMID:19943428

Descottes, Bernard; Lachachi, Fouzi; Maisonnette, Franck; Durand-Fontanier, Sylvaine; Abita, Thiare; Geballa, Rami; Valleix, Denis

2008-01-01

224

Reversibility of intrapulmonary arteriovenous shunts in liver cirrhosis documented by serial radionuclide perfusion lung scans  

SciTech Connect

Using serial perfusion lung scans, the opening up and closure of right-to-left intrapulmonary arteriovenous shunts has been documented over a period of several weeks in a patient with chronic alcoholic liver disease. The presence of the shunts correlates well with the severity of hypoxemia and the presence of nodular mottling on chest radiographs. The time course of these changes with clinical status suggests lability and the functional nature of these shunts.

Chen, N.S.; Barnett, C.A.; Farrer, P.A.

1984-05-01

225

Successful Embolization of a Spontaneous Mesocaval Shunt Using the Amplatzer Vascular Plug II  

Microsoft Academic Search

A 48-year-old man with alcoholic liver cirrhosis and hepatic encephalopathy was found to have a large, spontaneous mesocaval\\u000a shunt. The shunt was successfully occluded with the use of an Amplatzer Vascular Plug. To our knowledge, this is the first\\u000a report of the use of this device to embolize a mesocaval shunt involving the superior mesenteric vein.

Helena Boixadera; Alejandro Tomasello; Sergi Quiroga; Joan Cordoba; Mercedes Perez; Antoni Segarra

2010-01-01

226

Living donor liver transplantation for multiple intrahepatic portosystemic shunts after involution of infantile hepatic hemangiomas.  

PubMed

We describe a 6-year-old girl presenting with multiple intrahepatic portosystemic shunts after the involution of infantile hepatic hemangiomas (IHHs), who successfully underwent living donor liver transplantation. The chronological changes of radiologic findings indicated that remnant portovenous shunts at the time of IHHs involution developed gradually on the background of atrophic intrahepatic portal veins. This suggests that patients should be carefully followed up for the late onset of intrahepatic portosystemic shunts after the involution of IHHs. PMID:21683241

Sakamoto, Seisuke; Kasahara, Mureo; Shigeta, Takanobu; Fukuda, Akinari; Kakiuchi, Toshihiko; Miyasaka, Mikiko; Nosaka, Shunsuke; Nakano, Natsuko; Nakagawa, Atsuko; Horikawa, Reiko

2011-06-01

227

Perioperative risk factors for short term shunt revisions in adult hydrocephalus patients  

Microsoft Academic Search

Objectives:The aim of this study was to prospectively study perioperative variables associated with revision after shunt surgery for adult hydrocephalus.Methods:Two protocols were designed to prospectively study perioperative risk factors during shunt insertion. Over 10 years (1995–2004), 450 adult (age >16 years) patients with first time shunt implantations were studied. Patients who had been treated with endoscopic third ventriculostomy were excluded

D Farahmand; H Hilmarsson; M Högfeldt; M Tisell

2009-01-01

228

Radioimmunoassay of human plasma Lp(a) I i pop rote in  

Microsoft Academic Search

A quantitative immunodiffusion assay demon- strated Lp(a) lipoprotein in 91% (911 of 1000) of subjects. In order to quantitate Lp(a) in all plasma, a sensitive and specific double antibody radioimmunoassay was de- veloped. The between-assay coefficient of variation was 8%. Lp(a) levels by radioimmunoassay were highly correlated with those obtained by the less sensitive radial immuno- diffusion method (r =

John J. Albers; Janet L. Adolphson; William R. Hazzard

2009-01-01

229

Ultrasound-guided peripheral nerve blocks for ventricular shunt revision in children.  

PubMed

We describe using ultrasound-guided peripheral nerve blocks for postoperative pain control in 2 children undergoing ventricular shunt surgery. In the first patient undergoing ventriculo-peritoneal shunt revision, a combination of ultrasound-guided greater occipital nerve, superficial cervical plexus, and transversus abdominis plane blocks was used. In the second patient undergoing ventriculo-pleural shunt revision, a combination of ultrasound-guided greater occipital nerve, superficial cervical plexus, and intercostal blocks was used. Both patients, who underwent multiple revisions during their hospitalizations, showed decreased analgesic requirements after regional anesthesia. Our experience suggests this combined block technique may provide beneficial postoperative analgesia for patients undergoing shunt revision. PMID:25612197

King, Michael R; Anderson, T Anthony

2014-12-15

230

Portal venous remodeling after endovascular reduction of pediatric autogenous portosystemic shunts.  

PubMed

Patients with autogenous native vessel portosystemic shunts, whether surgical or congenital, may experience complications of excess shunt flow, including hepatopulmonary syndrome (HPS), hepatic encephalopathy (HE), and hepatic insufficiency. The authors explored endovascular reduction or occlusion of autogenous portosystemic shunts using methods commonly employed in transjugular intrahepatic portosystemic shunt (TIPS) reduction in four pediatric patients. Before treatment, the patients had hypoplastic, atrophic, or thrombosed portal veins. Following intervention, symptoms of overshunting resolved or improved in all patients without major complications. The innate plasticity of the pediatric portal venous system allowed for hypertrophy or development and maturation of cavernous transformations to accommodate increased hepatopetal blood flow and pressure. PMID:21801995

Stewart, Jessica K; Kuo, William T; Hovsepian, David M; Hofmann, Lawrence V; Bonham, Clark A; Sze, Daniel Y

2011-08-01

231

Cellophane banding of congenital intrahepatic portosystemic shunts in two Irish wolfhounds.  

PubMed

Two three-month-old, male Irish wolfhound siblings were diagnosed with breed-typical left divisional congenital intrahepatic portosystemic shunts consistent with patent ductus venosus. The shunts were amenable to surgical dissection at a posthepatic location. Both dogs had cellophane banding for shunt attenuation. One dog was euthanased after developing post-ligation neurological dysfunction, which was refractory to treatment. The other dog survived and demonstrated shunt attenuation. Successful surgical management using cellophane banding of a patent ductus venosus has not been previously described in a large-breed dog. PMID:12201443

Connery, N A; McAllister, H; Skelly, C; Pawson, P; Bellenger, C R

2002-08-01

232

Detection and evaluation of intrapulmonary vascular shunt with "contrast Doppler" transesophageal echocardiography.  

PubMed

Contrast echocardiography is useful for detecting intrapulmonary right-to-left shunt lesions. In a patient with suspected pulmonary arteriovenous fistula, contrast transesophageal echocardiography was used to demonstrate the presence of a right-to-left shunt. By use of a combination of two-dimensional echocardiography, contrast injection, and pulsed Doppler echocardiography, each pulmonary vein was successfully interrogated for evidence of contrast shunting. This case demonstrates that contrast transesophageal echocardiography is useful for the detection of intrapulmonary fistulas and that it has the potential for localization of the shunt lesion. PMID:2003943

Nemec, J J; Davison, M B; Marwick, T H; Chimowitz, M I; Stoller, J K; Klein, A L; Salcedo, E E

1991-01-01

233

[Ventriculoperitoneal and ventriculoatrial shunts in treatment of patients with brain tumors].  

PubMed

Two 234 patients with tumor-associated hydrocephalus underwent their first shunt implantation at Burdenko Neurosurgery Institute between 2004 and 2008. Age of the patients ranged from 18 to 77 years (mean 44). The follow-up was available in 162 patients (72%). The median follow-up was 10 months. Shunt failure occurred in 29,2% of 162 patients. Kaplan-Mayer analysis showed that the probability of shunt failure free interval was 72, 69, 60% at one, two and three years after insertion, respectively. The most frequent cause of shunt failure was malposition of the ventricular catheter (30,6%), occlusion of the ventricular and abdominal catheter occurred in 20,4 and 22,2%, respectively. Shunt infection was encountered in 24,5% of cases. Among the analyzed factors (position of the catheter within the ventricle, additional operations such as tumor resection, implantation of external ventricular drain before shunt surgery, malignancy of the tumor and type of hydrocephalus) only presence of external ventricular drain increased the risk of shunt infection. The duration of external drainage positively correlated with the risk of shunt infection. In most cases shunt failure can be prevented. The results of the study may help the surgeon to choose the optimal treatment strategy for patient with tumor-associated hydrocephalus. PMID:22379852

Omarov, A D; Kopachev, D N; Sanikidze, A Z; Zhukov, V Iu; Pitskhelauri, D I; Nepomniashchi?, V P

2011-01-01

234

20 Teams Participated Banded GGGOOOLLLDDD tip: Roos & Henning (LP) 99 species  

E-print Network

SSSIIILLLVVVEEERRR arrowhead: Highland Emperors (LP) 46 species Mocker BBBRRROOONNNZZZEEE: The Lazy Lepidopterists boeticus) Gauteng ­ 29 species Eyed Pansy (Junonia orithya madagascariensis) North West ­ 27 species Citrus

de Villiers, Marienne

235

Training Lp norm multiple kernel learning in the primal.  

PubMed

Some multiple kernel learning (MKL) models are usually solved by utilizing the alternating optimization method where one alternately solves SVMs in the dual and updates kernel weights. Since the dual and primal optimization can achieve the same aim, it is valuable in exploring how to perform Lp norm MKL in the primal. In this paper, we propose an Lp norm multiple kernel learning algorithm in the primal where we resort to the alternating optimization method: one cycle for solving SVMs in the primal by using the preconditioned conjugate gradient method and other cycle for learning the kernel weights. It is interesting to note that the kernel weights in our method can obtain analytical solutions. Most importantly, the proposed method is well suited for the manifold regularization framework in the primal since solving LapSVMs in the primal is much more effective than solving LapSVMs in the dual. In addition, we also carry out theoretical analysis for multiple kernel learning in the primal in terms of the empirical Rademacher complexity. It is found that optimizing the empirical Rademacher complexity may obtain a type of kernel weights. The experiments on some datasets are carried out to demonstrate the feasibility and effectiveness of the proposed method. PMID:23770740

Liang, Zhizheng; Xia, Shixiong; Zhou, Yong; Zhang, Lei

2013-10-01

236

Bacteria causing ventriculoperitoneal shunt infections in a Kenyan population.  

PubMed

OBJECT Ventriculoperitoneal shunt (VPS) infections are a major cause of morbidity and mortality in patients with hydrocephalus. Most data about these infections come from the Western literature. Few data about infecting organisms in Africa are available, yet knowledge of these organisms is important for the prevention and treatment of infectious complications. The purpose of this study was to determine the organisms cultured from infected shunts in a rural Kenyan hospital. METHODS The authors conducted a retrospective study of patients with VPS infections recorded in the neurosurgical database of BethanyKids at Kijabe Hospital between September 2010 and July 2012. RESULTS Among 53 VPS infections confirmed by culture, 68% occurred in patients who were younger than 6 months. Seventy-nine percent of the infections occurred within 2 months after shunt insertion. Only 51% of infections were caused by Staphylococcus species (Staphylococcus aureus 25%, other Staphylococcus species 26%), whereas 40% were caused by gram-negative bacteria. All S. aureus infections and 79% of other Staphylococcus infections were sensitive to cefazolin, but only 1 of 21 gram-negative bacteria was sensitive to it. The majority of gram-negative bacterial infections were multidrug resistant, but 17 of the 20 gram-negative bacteria were sensitive to meropenem. Gram-negative bacterial infections were associated with worse outcomes. CONCLUSIONS The high proportion of gram-negative infections differs from data in the Western literature, in which Staphylococcus epidermidis is by far the most common organism. Once a patient is diagnosed with a VPS infection in Kenya, immediate treatment is recommended to cover both gram-positive and gram-negative bacterial infections. Data from other Sub-Saharan countries are needed to determine if those countries have the same increased frequency of gram-negative infections. PMID:25431903

Ochieng', Naomi; Okechi, Humphrey; Ferson, Susan; Albright, A Leland

2014-11-28

237

Time to First Shunt Failure in Pediatric Patients over 1 Year Old: A 10-Year Retrospective Study.  

PubMed

Studies comparing alternatives to ventriculoperitoneal (VP) shunting for treatment of hydrocephalus have often relied upon data from an earlier era that may not be representative of contemporary shunt survival outcomes. We sought to determine the shunt survival rate of our cohort and compare our results to previously published shunt survival and endoscopic third ventriculostomy (ETV) success rates. We identified 95 patients between 1 and 18 years of age, who underwent initial VP shunt placement between January 2001 and December 2010. Our study shows a shunt survival rate of 85% at 6 months and 79% at 2 years, for initial shunts in pediatric patients over 1 year of age in this cohort. The overall infection rate was 3%. This compares favorably with published success rates of ETV at similar time points as well as with the rate of infection. This suggests that ventricular shunting remains a viable alternative to ETV in the older child. © 2014 S. Karger AG, Basel. PMID:25471222

Shannon, Chevis N; Carr, Kevin R; Tomycz, Luke; Wellons, John C; Tulipan, Noel

2014-11-27

238

Shunting arc plasma source for pure carbon ion beam.  

PubMed

A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA?mm(2) at the peak of the pulse. PMID:22380206

Koguchi, H; Sakakita, H; Kiyama, S; Shimada, T; Sato, Y; Hirano, Y

2012-02-01

239

Shunting arc plasma source for pure carbon ion beama)  

NASA Astrophysics Data System (ADS)

A plasma source is developed using a coaxial shunting arc plasma gun to extract a pure carbon ion beam. The pure carbon ion beam is a new type of deposition system for diamond and other carbon materials. Our plasma device generates pure carbon plasma from solid-state carbon material without using a hydrocarbon gas such as methane gas, and the plasma does not contain any hydrogen. The ion saturation current of the discharge measured by a double probe is about 0.2 mA/mm2 at the peak of the pulse.

Koguchi, H.; Sakakita, H.; Kiyama, S.; Shimada, T.; Sato, Y.; Hirano, Y.

2012-02-01

240

Radiation doses to children with shunt-treated hydrocephalus  

Microsoft Academic Search

Background  Children with shunt-treated hydrocephalus are still followed routinely with frequent head CT scans.\\u000a \\u000a \\u000a \\u000a Objective  To estimate the effective dose, brain and lens doses from these examinations during childhood, and to assess dose variation\\u000a per examination.\\u000a \\u000a \\u000a \\u000a Materials and methods  All children born between 1983 and 1995 and treated for hydrocephalus between 1983 and 2002 were included. We retrospectively\\u000a registered the number of examinations

Lise Jofrid Holmedal; Eva Godske Friberg; Ingelin Børretzen; Hilde Olerud; Liv Lægreid; Karen Rosendahl

2007-01-01

241

Piezoelectric vibration damping using resonant shunt circuits: an exact solution  

NASA Astrophysics Data System (ADS)

The objective of this paper is to propose an exact closed-form solution to the {{H}? } optimization of piezoelectric materials shunted with inductive-resistive passive electrical circuits. Realizing that Den Hartog?s method which imposes fixed points of equal height in the receptance transfer function is approximate, the parameters of the piezoelectric tuned vibration absorber are calculated through the direct minimization of the maxima of the receptance. The method is applied to a one-degree-of-freedom primary oscillator considering various values of the electromechanical coupling coefficients.

Soltani, P.; Kerschen, G.; Tondreau, G.; Deraemaeker, A.

2014-12-01

242

Transglandular cavernosum-spongiosum shunt for leukemic priapism in childhood.  

PubMed

Priapism is a complication rarely seen in childhood leukemia. Whatever the etiology the basic pathologic feature is obstruction to venous outflow from the corpora cavernosa. The cavernous bodies are erect but the glans penis and the corpus spongiosum usually remain soft. Various forms of treatment have been advocated for the management of this condition and have met with varying degrees of success. A boy with acute lymphocytic leukemia presented with priapism. Although radiation and chemotherapy induced prompt remission and dramatic decrease in leukocytosis, the priapism persisted. Resolution of the priapism was obtained using the transglandular cavernosum-spongiosum shunt. PMID:7354543

Altebarmakian, V K; Rabinowitz, R; Rana, S R; Ettinger, L J

1980-02-01

243

Portal anatomic variants relevant to transjugular intrahepatic portosystemic shunt.  

PubMed

Transjugular intrahepatic portosystemic shunt (TIPS) creation is an accepted treatment for portal hypertension. TIPS creation remains a challenging procedure because it involves the successful passage of a needle from a point of origin (hepatic vein) to a target point (portal vein) through the liver substance. An understanding of the anatomy of these two vascular beds facilitates overcoming the challenge of the spatial relationship between these two points. In this article the authors review the vascular and parenchymal anatomic variations, both congenital and acquired that impact the success of TIPS creation. PMID:19527845

Saad, Nael; Darcy, Michael; Saad, Wael

2008-12-01

244

Simultaneous endoscopic third ventriculostomy and ventriculoperitoneal shunt for infantile hydrocephalus  

Microsoft Academic Search

Objective  We analyzed a series of consecutive hydrocephalic infants treated with implantation of a ventriculoperitoneal shunt (VPS)\\u000a and endoscopic third ventriculostomy (ETV) simultaneously.\\u000a \\u000a \\u000a \\u000a Materials and methods  Between 1995 and 2006, we treated the 111 hydrocephalic infants. Among those patients, 31 infants underwent VPS and ETV simultaneously,\\u000a and 45 patients underwent only VPS. The ETV plus VPS group had 17 males and 14

Kyu-Won Shim; Dong-Seok Kim; Joong-Uhn Choi

2008-01-01

245

Endoscopic third ventriculostomy in previously shunted children: a retrospective study  

Microsoft Academic Search

Purpose  The aim of this study was to assess the mid-term results, success rates, and time-to-failure of secondary endoscopic third\\u000a ventriculostomy (secondary ETV), as well as the complex management of preoperative and postoperative cares.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  To this purpose, a retrospective analysis of a pediatric population of 22 children who underwent endoscopic third ventriculostomy\\u000a (ETV) after shunt malfunction (secondary ETV) was performed.\\u000a \\u000a \\u000a \\u000a \\u000a Results  The

Elisabetta Marton; Alberto Feletti; Luca Basaldella; Pierluigi Longatti

2010-01-01

246

HeLp, a heme lipoprotein from the hemolymph of the cattle tick, Boophilus microplus.  

PubMed

The main protein of the hemolymph of the cattle tick Boophilus microplus has been isolated and shown to be a heme lipoprotein (HeLp). HeLp has an apparent molecular mass of 354,000 and contains two apoproteins (103 and 92 kDa) found in equal amounts. HeLp presents a pI of 5.8 and a density of 1.28 g/ml and contains 33% lipids, containing both neutral lipids and phospholipids, and 3% of sugars. A remarkable feature of HeLp is the abundance of cholesterol ester (35% of total lipids), a lipid not previously reported in invertebrate lipoproteins. Western blot analysis showed HeLp in hemolymph from adult females and males, but not in eggs. Although HeLp contains 2 heme molecules, it is capable of binding 6 additional molecules of heme. Boophilus feeds large amount of blood, and we recently showed that this tick is unable to perform de novo synthesis of heme (Braz, G. R. C., Coelho, H. S. L., Masuda, H., and Oliveira, P. L. (1999) Curr. Biol. 9, 703-706). Injection of tick females with (55)Fe-labeled heme-HeLp indicated that this protein transports heme from hemolymph to tissues. HeLp is suggested to be an essential adaptation to the loss of the heme synthesis pathway. PMID:10964932

Maya-Monteiro, C M; Daffre, S; Logullo, C; Lara, F A; Alves, E W; Capurro, M L; Zingali, R; Almeida, I C; Oliveira, P L

2000-11-24

247

76 FR 35070 - Canexus Chemicals Canada L.P. v. BNSF Railway Company  

Federal Register 2010, 2011, 2012, 2013, 2014

...FD 35524] Canexus Chemicals Canada L.P. v. BNSF Railway Company AGENCY: Surface...be held Thursday, June 23, 2011, at 2 p.m., or at a later time that afternoon...INFORMATION: Canexus Chemicals Canada L.P. (Canexus) has filed a complaint...

2011-06-15

248

Linear Programming (LP) Formulation Problems Math 364: Principles of Optimization, Lecture 6  

E-print Network

Linear Programming (LP) Formulation Problems Math 364: Principles of Optimization, Lecture 6 Haijun Problems Staffing Problem: Linear Programming Formulation Haijun Li Math 364: Principles of Optimization;Linear Programming (LP) Formulation Problems Haijun Li Math 364: Principles of Optimization, Lecture 6

Li, Haijun

249

78 FR 11639 - Houston Pipe Line Company LP; Notice of Petition for Rate Approval  

Federal Register 2010, 2011, 2012, 2013, 2014

...Line Company LP; Notice of Petition for Rate Approval Take notice that on February 1, 2013, Houston Pipe Line Company LP (HPL) filed for approval of rates for transportation service pursuant to section 284.123(b)(2) of the Commission's...

2013-02-19

250

78 FR 21929 - TexStar Crude Oil Pipeline, LP; Notice of Filing  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF ENERGY Federal Energy Regulatory Commission...AC13-63-000] TexStar Crude Oil Pipeline, LP; Notice...March 26, 2013, TexStar Crude Oil Pipeline, LP (TexStar) submitted to the Federal Energy Regulatory...

2013-04-12

251

78 FR 71601 - Shell Pipeline Company LP; Notice of Petition for Declaratory Order  

Federal Register 2010, 2011, 2012, 2013, 2014

...Energy Regulatory Commission [Docket No. OR14-9-000] Shell Pipeline Company LP; Notice of Petition for Declaratory Order...Practices and Procedure, 18 CFR 385.207(a)(2)(2013), Shell Pipeline Company LP (SPLC) filed a petition requesting a...

2013-11-29

252

Automated Test Assembly Using lp_Solve Version 5.5 in R  

ERIC Educational Resources Information Center

This article reviews the use of the software program lp_solve version 5.5 for solving mixed-integer automated test assembly (ATA) problems. The program is freely available under Lesser General Public License 2 (LGPL2). It can be called from the statistical language R using the lpSolveAPI interface. Three empirical problems are presented to…

Diao, Qi; van der Linden, Wim J.

2011-01-01

253

76 FR 28026 - TransCanada Keystone Pipeline, LP; Notice of Request for Waiver  

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket No. OR11-7-000] TransCanada Keystone Pipeline, LP; Notice of Request for Waiver Take notice that on May 2, 2011, TransCanada Keystone Pipeline, LP (TransCanada Keystone) filed a request for waiver of the...

2011-05-13

254

78 FR 26358 - TransCanada Keystone Pipeline, LP; Notice of Petition for Declaratory Order  

Federal Register 2010, 2011, 2012, 2013, 2014

...Commission [Docket No. OR13-17-000] TransCanada Keystone Pipeline, LP; Notice of Petition for Declaratory Order Take...CFR 385.207(a)(2)(2012), TransCanada Keystone Pipeline, LP filed a petition seeking a declaratory...

2013-05-06

255

77 FR 36123 - Special Conditions: Gulfstream Aerospace LP (GALP), Model Gulfstream G280 Airplane; Aircraft...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Aerospace LP (GALP), Model Gulfstream G280 Airplane...Gulfstream Aerospace LP, Model Gulfstream G280 airplane...architecture and connectivity capabilities of the airplane's...services); and, 4. The capability to allow access to or...airplane. Discussion The Model G280 architecture...

2012-06-18

256

15 Aug 2003 Diffraction and Vector Meson Production, LP03 1 Diffraction and Vector  

E-print Network

15 Aug 2003 Diffraction and Vector Meson Production, LP03 1 Diffraction and Vector Meson Production and Photon Interactions at High Energies #12;Diffraction and Vector Meson Production, LP03 215 Aug 2003 Diffractive processes t-channel exchange of the vacuum quantum numbers Colourless exchange Small momentum

257

75 FR 74029 - Sabine Pass LNG, L.P.; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...Commission [Docket No. CP11-32-000] Sabine Pass LNG, L.P.; Notice of Application November 22, 2010. Take notice that on November 12, 2010, Sabine Pass LNG, L.P. (Sabine Pass), 700 Milam Street, Suite 800, Houston,...

2010-11-30

258

Electric arc furnace power quality improvement using shunt active filter and series inductor  

Microsoft Academic Search

This paper presents an investigation of power quality problems arising from electric arc furnace (EAF) operation, and the required compensating system capabilities. It also proposes a compensation system using a shunt active filter and a series inductor. A shunt active filter compensates for the reactive power and the current harmonics of the highly varying load. Reference signals for the compensation

Ahmad Esfandiari; Mostafa Parniani

2004-01-01

259

Pedunculated hepatic haemangioma with arterioportal shunt: treated with angio-embolization and surgery.  

PubMed

A case of symptomatic cavernous haemangioma of the liver with an unusual arterio-portal shunting, which was treated by pre-operative angiographic embolization, is described. The arterio-portal shunting has been reported previously in only two cases. PMID:9599833

Srivastava, D N; Sharma, S; Yadav, S; Nundy, S; Berry, M

1998-05-01

260

Shunt capacitor sizing for radial distribution feeders with distorted substation voltages  

Microsoft Academic Search

It is well known that a major portion of power system losses occur at the distribution level. Some of these losses can be eliminated by proper selection of shunt capacitors on primary feeders via power factor correction. The objective of this paper is to present an algorithm for optimizing shunt capacitor sizes on radial distribution lines with nonsinusoidal substation voltages,

Y. Baghzouz; S. Ertem

1990-01-01

261

Fast Energy Loss Computation and Fuzzy-Based Shunt Capacitor Insertion  

E-print Network

Fast Energy Loss Computation and Fuzzy-Based Shunt Capacitor Insertion Dr. W. F. Mohammad, Dr. N power, reactive power, load voltage, load current, power factor, and the shunt capacitors current. It is found that when 2.7 MVAR bank capacitor is inserted in the network the load current is decreased from

262

Electromagnetic Shunt Damping S. Behrens A. J. Fleming S. O. Reza Moheimani  

E-print Network

Electromagnetic Shunt Damping S. Behrens A. J. Fleming S. O. Reza Moheimani School of Electricalqhzfdvwoh1hgx1dx Abstract A method for electromagnetic shunt damping (EMSD) will be presented in this paper. A passive control strategy is validated through experi- mentation on a simple electromagnetic mass

Fleming, Andrew J.

263

Normal-pressure hydrocephalus: current understanding of diagnostic tests and shunting  

SciTech Connect

Normal-pressure hydrocephalus is no longer difficult to diagnose or treat-cranial computed tomographic scanning has made the diagnosis of ventricular enlargement straightforward, and shunt placement often helps the patient whose condition can be traced to a specific cause. Predicting accurately whether a patient will benefit from a shunt, however, is still problematic.

Black, P.M.

1982-02-01

264

The effect of alignment on the pressure\\/flow characteristics of flow control shunt valves  

Microsoft Academic Search

Object: The proper functioning of shunt valves in vivo is dependent on many factors, including the valve itself, the antisiphon device (if included), patency of inlet and outlet tubing and location of the valve. Two general categories of shunt valves are available today, the differential-pressure valve (with or without antisiphon device) and the flow-control valve. We have previously shown that

Paul C. Francel; John Honeycutt; Paul Tompkins

2001-01-01

265

Laparoscopy-Guided Insertion of Peritoneal Catheters in Ventriculoperitoneal Shunt Procedures: Analysis of 39 Children  

Microsoft Academic Search

Ventriculoperitoneal shunting is the mainstay in the treatment of hydrocephalus in childhood. Repeated shunt revision and previous laparotomy may complicate the implantation of the distal catheter. We describe our experience with laparoscopic insertion of peritoneal catheters in 21 male and 18 female children with an age range from 3 months to 18 years, operated between 2002 and 2004. Fourteen patients

Alan Bani; Werner E. Hassler

2006-01-01

266

Uniform model for series RL and parallel RL shunt circuits and power consumption  

Microsoft Academic Search

A simple impedance based analysis is presented for resonant shunt circuits. The formulation is compatible with arrangement of shunt electronics and is used to clarify previously published resonance condition and to examine power. Since our resonance condition is contrary to previously published results, experimental verification is also presented. The experiments consist of both a series and parallel second mode absorber

Chul H. Park; Daniel J. Inman

1999-01-01

267

Third Ventriculostomy versus Cerebrospinal Fluid Shunt as a First Procedure in Pediatric Hydrocephalus  

Microsoft Academic Search

Background: Third ventriculostomy (TV) has been reported to be efficacious for diverse causes of obstructive hydrocephalus in pediatric patients, and preferable to a first CSF shunt (CS) in those eligible. We reviewed the respective failure rates in a prospective cohort of patients at our institution. Method: All patients having either TV or CS (i.e ventriculoperitoneal shunt) over the period 1987

Sagun Tuli; Essam Alshail; James Drake

1999-01-01

268

78 FR 32294 - DeltaPoint Capital IV, L.P., DeltaPoint Capital IV (New York), L.P., License No. 02/02-0662,02/02...  

Federal Register 2010, 2011, 2012, 2013, 2014

...SMALL BUSINESS ADMINISTRATION DeltaPoint Capital IV, L.P., DeltaPoint...and DeltaPoint Capital IV (New York...the Small Business Administration (``SBA'') Rules...730). DeltaPoint Capital IV, L.P....

2013-05-29

269

Transcatheter venous embolization of a massive hepatic arteriovenous shunt complicating hepatocellular carcinoma using an Amplatzer Vascular Plug.  

PubMed

Arteriovenous (AV) shunts are relatively uncommon in the liver and usually associated with advanced hepatocellular carcinoma (HCC). In patients with massive AV shunts complicating advanced HCC, transarterial chemoinfusion therapy is not effective because chemotherapeutic agents go through the shunts and may cause systemic toxicity as well as decrease the chemotherapeutic effects against the tumor. We report two cases of successful transcatheter venous embolization of massive AV shunts complicating advanced HCC using the Amplatzer Vascular Plug for transarterial chemoinfusion therapy. PMID:21359943

Kim, Sun Ki; Chun, Ho Jong; Choi, Byung Gil; Lee, Hae Giu; Bae, Si Hyun; Choi, Jong Young

2011-02-01

270

Prevention of Arteriovenous Shunt Occlusion Using Microbubble and Ultrasound Mediated Thromboprophylaxis  

PubMed Central

Background Palliative shunts in congenital heart disease patients are vulnerable to thrombotic occlusion. High mechanical index (MI) impulses from a modified diagnostic ultrasound (US) transducer during a systemic microbubble (MB) infusion have been used to dissolve intravascular thrombi without anticoagulation, and we sought to determine whether this technique could be used prophylactically to reduce thrombus burden and prevent occlusion of surgically placed extracardiac shunts. Methods and Results Heparin?bonded ePTFE tubular vascular shunts of 4 mm×2.5 cm (Propaten; W.L Gore) were surgically placed in 18 pigs: a right?sided side?to?side arteriovenous (AV, carotid?jugular) shunt, and a left?sided arterio?arterial (AA, carotid?carotid) interposition shunt in each animal. After shunt implantation, animals were randomly assigned to one of 3 groups. Transcutaneous, weekly 30?minute treatments (total of 4 treatments) of either guided high MI US+MB (Group 1; n=6) using a 3% MRX?801 MB infusion, or US alone (Group 2; n=6) were given separately to each shunt. The third group of 6 pigs received no treatments. The shunts were explanted after 4 weeks and analyzed by histopathology to quantify luminal thrombus area (mm2) for the length of each shunt. No pigs received antiplatelet agents or anticoagulants during the treatment period. The median overall thrombus burden in the 3 groups for AV shunts was 5.10 mm2 compared with 4.05 mm2 in AA (P=0.199). Group 1 pigs had significantly less thrombus burden in the AV shunts (median 2.5 mm2) compared with Group 2 (median 5.6 mm2) and Group 3 (median 7.5 mm2) pigs (P=0.006). No difference in thrombus burden was seen between groups for AA shunts. Conclusion Transcutaneous US with intravenous MB is capable of preventing thrombus accumulation in arteriovenous shunts without the need for antiplatelet agents, and may be a method of preventing progressive occlusion of palliative shunts. PMID:24518555

Kutty, Shelby; Wu, Juefei; Hammel, James M.; Abraham, Joseph R.; Venkataraman, Jeeva; Abdullah, Ibrahim; Danford, David A.; Radio, Stanley J.; Lof, John; Porter, Thomas R.

2014-01-01

271

78 FR 32294 - Main Street Capital ll, L.P., License No. 06/06-0332; Notice Seeking Exemption Under Section 312...  

Federal Register 2010, 2011, 2012, 2013, 2014

...SMALL BUSINESS ADMINISTRATION Main Street Capital ll, L.P., License...that Main Street Capital ll, L.P., 1300...the Small Business Administration (``SBA'') Rules...730). Main Street Capital ll, L.P....

2013-05-29

272

78 FR 69516 - DeltaPoint Capital IV, L.P.; License No. 02/02-0662; Notice Seeking Exemption Under the Small...  

Federal Register 2010, 2011, 2012, 2013, 2014

...SMALL BUSINESS ADMINISTRATION DeltaPoint Capital IV, L.P.; License...given that DeltaPoint Capital IV, L.P., 45...the Small Business Administration (``SBA'') Rules...730). DeltaPoint Capital IV, L.P....

2013-11-19

273

HeLp, a heme-transporting lipoprotein with an antioxidant role.  

PubMed

Plasma lipoproteins involved in lipid transport are target for free radical-evoked pathological conditions in several mammalian models. The main hemolymphatic protein of Boophilus microplus is a heme-binding lipoprotein (HeLp, for Heme LipoProtein) that carries dietary heme produced from degradation of vertebrate hemoglobin to tissues of the tick. Addition of heme to phospholipid liposomes resulted in intense lipid peroxidation, which was inhibited by addition of HeLp. HeLp prevented lysis of red blood cells by heme. HeLp also inhibited reactions of heme with tert-butyl hydroperoxide (t-BOOH) or hydrogen peroxide. HeLp, quite differently from other lipoproteins, presents a protective intrinsic mechanism to counteract heme toxicity, while preserving the heme molecule to be reused by the tick. This is the first report of a lipoprotein acting as an antioxidant particle against heme-induced radical damage. PMID:14976984

Maya-Monteiro, Clarissa M; Alves, Liliane R; Pinhal, Nelson; Abdalla, Dulcineia S P; Oliveira, Pedro L

2004-01-01

274

Clarkson's type inequalities for positive $l_p$ sequences with $p\\ge 2$  

E-print Network

For a fixed $1\\le p<+\\infty$ denote by $\\Vert\\cdot\\Vert_p$ the usual norm in the space $l_p$ (or $L_p$). In this paper we prove that for all real numbers $p$ and $q$ such that $2\\le p\\le q$ holds $$ 2(\\Vert x\\Vert_p^q+\\Vert y\\Vert_p^q)\\le \\Vert x+y\\Vert_p^q +\\Vert x-y\\Vert_p^q $$ for all nonnegative sequences $x=\\{x_n\\},y=\\{y_n\\}$ in $l_p$ (or nonnegative functions $x,y$ in $L_p$). Note that the above inequality with $p=q\\ge 2$ reduces to the well known Clarkson's inequality. If in addition, holds $x_i\\ge y_i$ for each $i=1,2,...$ (or $x\\ge y$ a.e. in $L_p$), then we establish an improvement of the above inequality.

Mestrovic, Romeo

2011-01-01

275

Improvement of image quality of time-domain diffuse optical tomography with lp sparsity regularization  

PubMed Central

An lp (0 < p ? 1) sparsity regularization is applied to time-domain diffuse optical tomography with a gradient-based nonlinear optimization scheme to improve the spatial resolution and the robustness to noise. The expression of the lp sparsity regularization is reformulated as a differentiable function of a parameter to avoid the difficulty in calculating its gradient in the optimization process. The regularization parameter is selected by the L-curve method. Numerical experiments show that the lp sparsity regularization improves the spatial resolution and recovers the difference in the absorption coefficients between two targets, although a target with a small absorption coefficient may disappear due to the strong effect of the lp sparsity regularization when the value of p is too small. The lp sparsity regularization with small p values strongly localizes the target, and the reconstructed region of the target becomes smaller as the value of p decreases. A phantom experiment validates the numerical simulations. PMID:22162823

Okawa, Shinpei; Hoshi, Yoko; Yamada, Yukio

2011-01-01

276

Hepatic Arterial Infusion Chemotherapy Combined with Venous Embolization in a Patient with Hepatic Metastases with an Arteriovenous Shunt  

SciTech Connect

We describe herein a patient who had hepatic metastases with an arteriovenous shunt and was treated by hepatic arterial infusion chemotherapy. The arteriovenous shunt was diagnosed by {sup 99m}Tc-macroaggregated albumin scintigraphy and hepatic venous embolization was performed to reduce shunt flow.

Nishiofuku, Hideyuki; Tanaka, Toshihiro, E-mail: toshihir@bf6.so-net.ne.j [Nara Medical University, Department of Radiology (Japan); Sakaguchi, Hiroshi [Nara Prefectural Mimuro Hospital, Department of Radiology (Japan); Yamamoto, Kiyosei; Inoue, Masayoshi; Sueyoshi, Satoru [Nara Medical University, Department of Radiology (Japan); Shinnkai, Takayuki; Hasegawa, Masatoshi [Nara Medical University, Department of Nuclear Medicine and Oncoradiology (Japan); Kichikawa, Kimihiko [Nara Medical University, Department of Radiology (Japan)

2009-07-15

277

Control strategy and site selection of a shunt active filter for damping of harmonic propagation in power distribution systems  

Microsoft Academic Search

This paper deals with a shunt active filter which will be installed by an electric utility, putting much emphasis on the control strategy and the best point of installation of the shunt active filter on a feeder in a power distribution system. The objective of the shunt active filter is to damp harmonic propagation, which results from harmonic resonance between

H. Akagi; Hirofumi

1997-01-01

278

Endoscopic Transtentorial Ventriculocystostomy and Cystoventriculoperitoneal Shunt in a Neonate with Dandy-Walker Malformation and Associated Aqueductal Obstruction  

Microsoft Academic Search

Objective: Shunting of the lateral ventricle and the posterior fossa cyst is the advocated surgical therapy for children with Dandy-Walker malformation (DWM) and associated aqueductal obstruction. The high rate of complications of combined shunting stimulated the authors to search for an alternative surgical solution. Clinical Presentation\\/Intervention: After transtentorial endoscopic ventriculocystostomy, a cystoventricular catheter, connected to a peritoneal shunt, was placed

Martin R. Weinzierl; Volker A. Coenen; Marcus C. Korinth; Joachim M. Gilsbach; Veit Rohde

2005-01-01

279

Prediction of the becalmed region for LP turbine profile design  

SciTech Connect

Recent attention has focused on the so-called ``becalmed region`` that is observed inside the boundary layers of turbomachinery blading and is associated with the process of wake-induced transition. Significant reductions of profile loss have been shown for high lift LP turbine blades at low Reynolds numbers due to the effects of the becalmed region on the diffusing flow at the rear of the suction surface. In this paper the nature and the significance of the becalmed region are examined using experimental observations and computational studies. It is shown that the becalmed region may be modeled using the unsteady laminar boundary layer equations. Therefore, it is predictable independent of the transition or turbulence models employed. The effect of the becalmed region on the transition process is modeled using a spot-based intermittency transition model. An unsteady differential boundary layer code was used to simulate a deterministic experiment involving an isolated turbulent spot numerically. The predictability of the becalmed region means that the rate of entropy production can be calculated in that region. It is found to be of the order of that in a laminar boundary layer. It is for this reason and because the becalmed region may be encroached upon by pursuing turbulent flows that for attached boundary layers, wake-induced transition cannot significantly reduce the profile loss. However, the becalmed region is less prone to separation than a conventional laminar boundary layer. Therefore, the becalmed region may be exploited in order to prevent boundary layer separation and the increase in loss that this entails. It is shown that it should now be possible to design efficient high lift LP turbine blades.

Schulte, V. [BMW Rolls-Royce GmbH, Dahlewitz (Germany); Hodson, H.P. [Cambridge Univ. (United Kingdom). Whittle Lab.

1998-10-01

280

76 FR 63822 - Special Conditions: Gulfstream Aerospace LP (GALP) Model G280 Airplane, Limit Engine Torque Loads...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Conditions No. 25-447-SC] Special Conditions: Gulfstream Aerospace LP (GALP) Model G280 Airplane, Limit Engine Torque Loads...SUMMARY: These special conditions are issued for the Gulfstream Aerospace LP (GALP) model G280 airplane. This airplane will...

2011-10-14

281

76 FR 63823 - Special Conditions: Gulfstream Aerospace LP (GALP) Model G280 Airplane Pilot-Compartment View...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Notice No. 25-449-SC] Special Conditions: Gulfstream Aerospace LP (GALP) Model G280 Airplane Pilot-Compartment View...SUMMARY: These special conditions are issued for the Gulfstream Aerospace LP (GALP) Model G280 airplane. This airplane will...

2011-10-14

282

75 FR 80047 - Equitrans, L.P., Big Sandy Pipeline, LLC; Notice of Joint Application for Abandonment and...  

Federal Register 2010, 2011, 2012, 2013, 2014

...No. CP11-43-000] Equitrans, L.P., Big Sandy Pipeline, LLC; Notice of Joint Application for...2010, Equitrans L.P. (Equitrans) and Big Sandy Pipeline, LLC (Big Sandy), 625 Liberty Avenue, Suite 1700,...

2010-12-21

283

77 FR 33716 - Foreign-Trade Zone 70-Detroit, MI; Expansion of Subzone; Marathon Petroleum Company LP, (Oil...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Foreign-Trade Zone 70--Detroit, MI; Expansion of Subzone; Marathon Petroleum Company LP, (Oil Refinery) Detroit, MI An application...70, requesting an expansion of Subzone 70T, on behalf of Marathon Petroleum Company LP in Detroit, Michigan. The...

2012-06-07

284

78 FR 18583 - Piedmont Energy Fund, LP; Supplemental Notice That Initial Market-Based Rate Filing Includes...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Energy Regulatory Commission [Docket No. ER13-1135-000] Piedmont Energy Fund, LP; Supplemental Notice That Initial Market-Based...supplemental notice in the above-referenced proceeding, of Piedmont Energy Fund, LP's application for market-based rate...

2013-03-27

285

75 FR 57017 - Enbridge Pipelines (North Dakota) LLC; Enbridge Pipelines (Bakken) L.P.; Notice of Petition for...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Pipelines (North Dakota) LLC; Enbridge Pipelines (Bakken) L.P.; Notice of Petition for Declaratory...Dakota) LLC (EPND) and Enbridge Pipelines (Bakken) L.P. (Enbridge Bakken U.S.) (collectively, Petitioners)...

2010-09-17

286

75 FR 19643 - West Oaks Energy LP; Supplemental Notice That Initial Market-Based Rate Filing Includes Request...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Regulatory Commission [Docket No. ER10-1029-000] West Oaks Energy LP; Supplemental Notice That Initial Market- Based Rate...supplemental notice in the above-referenced proceeding of West Oaks Energy LP's application for market-based rate...

2010-04-15

287

78 FR 62344 - Sabine Pass Liquefaction Expansion, LLC, Sabine Pass Liquefaction, LLC, and Sabine Pass LNG, L.P...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Commission [Docket No. CP13-552-000; Docket No. CP13-553-000] Sabine Pass Liquefaction Expansion, LLC, Sabine Pass Liquefaction, LLC, and Sabine Pass LNG, L.P., Cheniere Creole Trail Pipeline, L.P.; Notice of...

2013-10-18

288

Instantiating a mechatronic valve schedule for a hydrocephalus shunt.  

PubMed

Hydrocephalus is caused by blockage or reabsorption difficulty that upsets the natural balance of production and absorption of cerebrospinal fluid in the brain, resulting in a build-up of the fluid in the ventricles of the brain. One of the recent advances in the treatment of hydrocephalus is the invention of a mechatronic valve. The desirability of such valve lies in the potential of having shunt that not only control hydrocephalus but also seeks to treat it. In contrast to current valves, such a valve is regulated based on a time based schedule not on the differential pressure across the valve. Thus the effectiveness of such valve is highly dependant on selecting an appropriate valve schedule that delivers personal dynamic treatment for every individual patient. Providing such a schedule is likely to be one of the obstacles facing the implementation of the mechatronic valve. In this paper, an algorithm is proposed to help in developing such a schedule that dynamically change based on the patients' own intracranial pressure data and a novel figure of merit, thus providing the physician with an easy tool that facilitate the use of the mechatronic valve. The algorithm was implemented in M ATLAB and Simulink. Real ICP data for three hydrocephalus patients (before shunting) were used to test this algorithm and the resulted schedules along with the resulted intracranial pressure data have illustrated the effectiveness of the algorithm in providing schedule that maintain ICP within the normal limits. PMID:19963474

Momani, Lina; Alkharabsheh, Abdel Rahman; Al-Zuibi, Nayel; Al-Nuaimy, Waleed

2009-01-01

289

Fabrication and characterization of shunted μ-SQUID  

NASA Astrophysics Data System (ADS)

In order to eliminate hysteresis, we have fabricated and characterized niobium based shunted micron size superconducting quantum interference devices (?-SQUIDs). We find a wide temperature range where these ?-SQUIDs are non-hysteretic in nature and show a very good Ic vs. B oscillations in hysteretic regime and V vs. B oscillations in non-hysteretic regime. Here we report the characteristics of a shunted- ?-SQUID (Wf38LS72D5). In this device we have achieved a large voltage modulation, in non-hysteretic regime, at various temperatures including such as 1.1 mV at 6.62 K with a transfer function V? = 7.2mV/?0. The figures within the original article PDF file, as supplied to AIP Publishing, were affected by a PDF-processing error. Consequently, the article re-flowed and pagination increased from 3 to 4 pages. This article was updated on 14 May 2014 to correct the PDF-processing error, with the scientific content remaining unchanged. Readers are advised that the replacement article PDF file contains an additional blank page to preserve the original pagination.

Kumar, Nikhil; Fournier, T.; Courtois, H.; Gupta, Anjan K.

2014-04-01

290

Improved piezoelectric switch shunt damping technique using negative capacitance  

NASA Astrophysics Data System (ADS)

This paper proposes an adaptive shunt damping circuit for improved damping performance. It consists of a switched inductance-resistance network (SSDI), which is connected in parallel to a negative capacitance. This circuit is in the following called 'synchronized switching damping on negative capacitor and inductor' (SSDNCI). It combines the adaptive nature of the SSDI technique and the improved performance of a negative capacitance. By the action of the switch device, the piezoelectric element is periodically held under both states of the nonlinear shunt and therefore adapts to the frequency of excitation. The analysis in this publication is performed based on the typical assumptions of a single degree-of-freedom oscillator. The stationary charge signal and energy dissipation are derived as functions of the ratio between the negative capacitance and piezoelectric capacitance. Calculation results show that the dissipated energy grows with the negative capacitance up to the stability boundary of the system. Measurements are conducted on a clamped beam test rig to validate the theoretical results. In the operative range of the negative capacitance which is used in this research, an increase in nearly 220% in energy dissipation compared to the standard SSDI technique is achieved.

Han, Xu; Neubauer, Marcus; Wallaschek, Jörg

2013-01-01

291

77 FR 75489 - Hatteras Venture Partners IV SBIC, L.P.; Application No. 99000769; Notice Seeking Exemption Under...  

Federal Register 2010, 2011, 2012, 2013, 2014

...SMALL BUSINESS ADMINISTRATION Hatteras Venture Partners IV SBIC, L.P.; Application...Interest Notice is hereby given that Hatteras Venture Partners IV SBIC, L.P., 280 South...Regulations (13 CFR 107.730). Hatteras Venture Partners IV SBIC, L.P. proposes...

2012-12-20

292

78 FR 63560 - Notice of Receipt of an Application by Magellan Pipeline Company, L.P., for Issuance of a...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Application by Magellan Pipeline Company, L.P., for Issuance of a Presidential Permit...Application by Magellan Pipeline Company, L.P., for Issuance of a Presidential Permit...received from Magellan Pipeline Company, L.P. (``Magellan'') notice that it...

2013-10-24

293

75 FR 32230 - Solutions Capital I, L.P.; Notice Seeking Exemption Under Section 312 of the Small Business...  

Federal Register 2010, 2011, 2012, 2013, 2014

...SMALL BUSINESS ADMINISTRATION [License No...03-0247] Solutions Capital I, L.P.; Notice...Small Business Administration (``SBA...730). Solutions Capital I, L.P. proposes...Associate of Solutions Capital I, L.P., as...Small Business Administration, 409 Third...

2010-06-07

294

75 FR 3502 - KLH Capital, L.P.; Notice Seeking Exemption Under 312 of the Small Business Investment Act...  

Federal Register 2010, 2011, 2012, 2013, 2014

...SMALL BUSINESS ADMINISTRATION [License No. 04/04-0296] KLH Capital, L.P.; Notice...Small Business Administration (``SBA...2006)). KLH Capital, L.P. proposes...Associate of KLH Capital, L.P. as...Small Business Administration, 409 Third...

2010-01-21

295

75 FR 64306 - Shell Energy North America (US), LP; Notice of Institution of Proceeding and Refund Effective Date  

Federal Register 2010, 2011, 2012, 2013, 2014

...ER08-656-007; EL10-83-000] Shell Energy North America (US), LP; Notice...concerning the justness and reasonableness of Shell Energy North America (US), LP's market...and Southwest balancing authority area. Shell Energy North America (US), LP,...

2010-10-19

296

Impact of Differential Right-to-Left Shunting on Systemic Perfusion in Pulmonary Arterial Hypertension  

PubMed Central

Objectives This study aimed at identifying the ideal right-to-left shunt-fraction to improve cardiac output (CO) and systemic perfusion in pulmonary arterial hypertension (PHT). Background Atrial septostomy has been a high-risk therapeutical option for symptomatic drug-refractory patients with PHT. Results have been unpredictable due to limited knowledge of the optimal shunt-quantity. Methods In 9 dogs, an 8-mm shunt-prosthesis was inserted between the superior vena cava (SVC) and the left atrium. With pulmonary artery banding, mean (±SEM) systolic right ventricular pressure increased from 37±1 mmHg at baseline to 44±1 mmHg (moderate PHT, P=0.005) and 50±2 mmHg (severe PHT, P<0.001). Shunt-flow was adjusted by total (forcing all flow through the shunt) or partial occlusion of the SVC and partial or total clamping of the shunt. Caval-, shunt- and aortic-flow were measured by ultrasonic flow-probes. Blood gases were drawn from the aortic root and pulmonary artery. Results At severe PHT, a shunt-flow of 11±1% of CO (253±90 mL/min) increased CO significantly by 25% (1.8±0.1 to 2.4±0.2 L/min, P=0.005) causing an increase of systemic oxygen delivery index (DO2I) by 23% (309±23 to 399±32 mL/min/M2, P=0.035). Arterial O2-saturation did not change significantly until a shunt-flow of 18±2% was exceeded, causing a drop from 96±1% to 84±4% (P=0.013). At moderate PHT, CO or DO2I did not improve significantly at any shunt-flow. Conclusions In severe PHT, a shunt-flow of 11% of CO represented the ideal shunt-fraction. Augmentation of CO compensated for declined O2-saturation due to right-to-left shunting and improved DO2I. In moderate PHT, atrial septostomy is less promising. PMID:22511538

Weimar, Timo; Watanabe, Yoshiyuki; Kazui, Toshinobu; Lee, Urvi S.; Montecalvo, Alessandro; Schuessler, Richard B.; Moon, Marc R.

2012-01-01

297

Infection rates following initial cerebrospinal fluid shunt placement across pediatric hospitals in the United States  

PubMed Central

Object Reported rates of CSF shunt infection vary widely across studies. The study objective was to determine the CSF shunt infection rates after initial shunt placement at multiple US pediatric hospitals. The authors hypothesized that infection rates between hospitals would vary widely even after adjustment for patient, hospital, and surgeon factors. Methods This retrospective cohort study included children 0–18 years of age with uncomplicated initial CSF shunt placement performed between January 1, 2001, and December 31, 2005, and recorded in the Pediatric Health Information System (PHIS) longitudinal administrative database from 41 children's hospitals. For each child with 24 months of follow-up, subsequent CSF shunt infections and procedures were determined. Results The PHIS database included 7071 children with uncomplicated initial CSF shunt placement during this time period. During the 24 months of follow-up, these patients had a total of 825 shunt infections and 4434 subsequent shunt procedures. Overall unadjusted 24-month CSF shunt infection rates were 11.7% per patient and 7.2% per procedure. Unadjusted 24-month cumulative incidence rates for each hospital ranged from 4.1 to 20.5% per patient and 2.5–12.3% per procedure. Factors significantly associated with infection (p < 0.05) included young age, female sex, African-American race, public insurance, etiology of intraventricular hemorrhage, respiratory complex chronic condition, subsequent revision procedures, hospital volume, and surgeon case volume. Malignant lesions and trauma as etiologies were protective. Infection rates for each hospital adjusted for these factors decreased to 8.8–12.8% per patient and 1.4–5.3% per procedure. Conclusions Infections developed in > 11% of children who underwent uncomplicated initial CSF shunt placements within 24 months. Patient, hospital, and surgeon factors contributed somewhat to the wide variation in CSF shunt infection rates across hospitals. Additional factors may contribute to variation in CSF shunt infection rates between centers, but further study is needed. Benchmarking and future prospective multicenter studies of CSF shunt infection will need to incorporate these and other patient, hospital, and surgeon factors. PMID:19645551

Simon, Tamara D.; Hall, Matthew; Riva-Cambrin, Jay; Albert, J. Elaine; Jeffries, Howard E.; LaFleur, Bonnie; Dean, J. Michael; Kestle, John R. W.

2010-01-01

298

Characterization of the apoLp-III/LPS complex: insight in the mode of binding interaction  

PubMed Central

Apolipoproteins are able to associate with lipopolysaccharides (LPS), potentially providing protection against septic shock. To gain insight in the molecular details of this binding interaction, apolipophorin III (apoLp-III) from Galleria mellonella was used as a model. The binding of apoLp-III to LPS was optimal around 37–40 °C, close to the LPS phase transition temperature. ApoLp-III formed complexes with LPS from E. coli (serotype O55:B5) with a diameter of 24 nm, a molecular weight of ~390 kDa, containing four molecules of apoLp-III and 24 molecules of LPS. The LPS-bound form of the protein was substantially more resistant to guanidine-induced denaturation compared to unbound protein. The denaturation profile displayed a multiphase character with a steep drop in secondary structure between 0–1 M guanidine, and a slower decrease above 1 M guanidine HCl. In contrast, apoLp-III bound to detoxified LPS was only slightly more resistant to guanidine HCl induced denaturation compared to unbound protein. Analysis of size-exclusion FPLC elution profiles of mixtures of apoLp-III with LPS or detoxified LPS indicated a much weaker binding interaction with detoxified LPS compared to intact LPS. These results indicate that apoLp-III initially interacts with exposed carbohydrate regions, but that the lipid A region is required for a more stable LPS binding interaction. PMID:22779761

Oztug, Merve; Martinon, Daisy; Weers, Paul M.M.

2012-01-01

299

Evaluation of magnetostrictive shunt damper performance using Iron (Fe)-Gallium (Ga) alloy  

NASA Astrophysics Data System (ADS)

This study presents the possibility of dissipating mechanical energy with a proof-of-concept prototype magnetostrictive based shunt circuit using passive electrical components. The device consists of a polycrystalline galfenol (Fe-Ga alloy) strip bonded to a brass cantilever beam. Two brass pieces, each containing a permanent magnet, are used to mass load each end of the beam and to provide a magnetic bias field through the galfenol strip. The voltage induced in an induction coil closely wound around the cantilever beam captures the time rate of change of magnetic flux within the galfenol strip as the beam vibrates. The first bending-mode resonant frequency of the device was 69.42 Hz. To dissipate the electrical voltage from the device, a shunt circuit is attached. The effective mechanical impedance for the magnetostrictive shunt circuit is derived. The shunted model is specialized for two shunt circuits: the case of a resistor and that of a capacitance. The experimental results for both the resistive and capacitance shunt circuits validate the shunted magnetostrictive damping model for couple of cased of resistance and capacitance.

Yoo, JinHyeong; Murray, Andrew; Flatau, Alison B.

2014-04-01

300

Correlation of experimental rCBF determinations in goats with flow measurements from a Doppler-modified carotid artery shunt  

SciTech Connect

A carotid artery shunt system has been developed that continuously monitors blood flow rates by embedding a Doppler crystal in the shunt wall. The crystal ranges through a liquid lens that enables it to be placed without violation of the shunt lumen. Because the crystal is at a fixed angle (45 degrees) to the axis of blood flow and the diameter of the lumen remains constant, a linear relationship exists between flow rates and the Doppler velocity signal. This shunt system was previously tested in vitro using a pulsatile pump and was found to be accurate to within 4.7% of the actual flow rate. In the present study, animal (goat) experiments were performed consisting of simultaneous carotid shunt flow and bilateral rCBF measurements by the radiolabeled microsphere technique to determine in vivo the accuracy of this Doppler modified shunt and to ascertain the ability of shunt flow to increase in the face of acute contralateral carotid occlusion. Data from five animals show that in vivo shunt flow can be recorded to within 13% of control rCBF and that shunt flow increases nearly 50% under conditions of distal demand (contralateral carotid occlusion). This device may prove useful in laboratory studies of carotid shunt dynamics and in clinical practice to quickly detect correctable shunt flow abnormalities.

Loftus, C.M.; Silvidi, J.A.; Becker, J.A.; Miller, B.V.; Bernstein, D.D.

1989-01-01

301

Staged Transcatheter Treatment of Portal Hypoplasia and Congenital Portosystemic Shunts in Children  

SciTech Connect

Purpose: Congenital portosystemic shunts (CPSS) with portal venous hypoplasia cause hyperammonemia. Acute shunt closure results in portal hypertension. A transcatheter method of staged shunt reduction to afford growth of portal vessels followed by shunt closure is reported. Methods: Pressure measurements and angiography in the CPSS or superior mesenteric artery (SMA) during temporary occlusion of the shunt were performed. If vessels were diminutive and the pressure was above 18 mmHg, a staged approach was performed, which included implantation of a tailored reducing stent to reduce shunt diameter by {approx}50 %. Recatheterization was performed approximately 3 months later. If the portal pressure was below 18 mmHg and vessels had developed, the shunt was closed with a device. Results: Six patients (5 boys, 1 girl) with a median age of 3.3 (range 0.5-13) years had CPSS portal venous hypoplasia and hyperammonemia. Five patients underwent staged closure. One patient tolerated acute closure. One patient required surgical shunt banding because a reducing stent could not be positioned. At median follow-up of 3.8 (range 2.2-8.4) years, a total of 21 procedures (20 transcatheter, 1 surgical) were performed. In all patients, the shunt was closed with a significant reduction in portal pressure (27.7 {+-} 11.3 to 10.8 {+-} 1.8 mmHg; p = 0.016), significant growth of the portal vessels (0.8 {+-} 0.5 to 4.0 {+-} 2.4 mm; p = 0.037), and normalization of ammonia levels (202.1 {+-} 53.6 to 65.7 {+-} 9.6 {mu}mol/L; p = 0.002) with no complications. Conclusion: Staged CPSS closure is effective in causing portal vessel growth and treating hyperammonemia.

Bruckheimer, Elchanan, E-mail: elchananb@bezeqint.net; Dagan, Tamir [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel)] [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel); Atar, Eli; Schwartz, Michael [Schneider Children's Medical Center Israel, Section of Radiology (Israel)] [Schneider Children's Medical Center Israel, Section of Radiology (Israel); Kachko, Ludmila [Schneider Children's Medical Center Israel, Section of Anesthesiology (Israel)] [Schneider Children's Medical Center Israel, Section of Anesthesiology (Israel); Superina, Riccardo; Amir, Gabriel [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel)] [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel); Shapiro, Rivka [Schneider Children's Medical Center Israel, Section of Gastroenterology (Israel)] [Schneider Children's Medical Center Israel, Section of Gastroenterology (Israel); Birk, Einat [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel)] [Schneider Children's Medical Center Israel, Section of Pediatric Cardiology (Israel)

2013-12-15

302

Neural Network Based Modeling and Analysis of LP Control Surface Allocation  

NASA Technical Reports Server (NTRS)

This paper presents an approach to interpretive modeling of LP based control allocation in intelligent flight control. The emphasis is placed on a nonlinear interpretation of the LP allocation process as a static map to support analytical study of the resulting closed loop system, albeit in approximate form. The approach makes use of a bi-layer neural network to capture the essential functioning of the LP allocation process. It is further shown via Lyapunov based analysis that under certain relatively mild conditions the resulting closed loop system is stable. Some preliminary conclusions from a study at Ames are stated and directions for further research are given at the conclusion of the paper.

Langari, Reza; Krishnakumar, Kalmanje; Gundy-Burlet, Karen

2003-01-01

303

Quantitative genetic studies of the human plasma Lp(a) lipoprotein  

Microsoft Academic Search

Lp(a) lipoprotein [Lp(a)] was quantified in 1251 adults, including 300 mother-father-offspring triplets, by a sensitive radial immunodiffusion assay. Lp(a) was not correlated with age, sex, or cholesterol or glyceride concentrations. Significant correlations were found between mother-offspring (r=0.34), father-offspring (r=0.40), and midparent-offspring (r=0.52), whereas no correlation was found between husband-wife pairs (r=0.02). Analysis of triplets separated on the basis of midparent

John J. Albers; Patricia Wahl; William R. Hazzard

1974-01-01

304

Optical manipulation of biological particles using LP21 mode in fiber  

NASA Astrophysics Data System (ADS)

We demonstrate the optical manipulation of biological particles using a low-order LP21 fiber mode. The focused four-lobed LP21 mode distribution was theoretically and experimentally found to be effective in optical tweezer applications, including selective cellular pick-up, pairing, grouping or separation, as well as rotation of cell dimers and clusters. Our proposed theoretical model estimates both the translational dragging force and rotational torque in good accordance with experimental data. With a simple all-fiber configuration, and low peak irradiation to target bioparticles, the proposed LP21 ‘optical chuck’ system has great application potential in biological test systems.

Chen, Shijie; Huang, He; Zou, Hongmei; Li, Qing; Fu, Jian; Lin, Feng; Wu, X.

2014-12-01

305

Traumatic Portacaval Shunt: A Case Report and Literature Review  

PubMed Central

Computed tomography (CT) evaluation of the acute polytrauma patient has become well established as a mainstay of ER triage in hemodynamically stable patients. The radiologist plays a pivotal role in directing management by identifying and appropriately categorizing the severity of a patient’s injuries. High-grade liver injuries have undergone an increasing trend of nonoperative management over the last several decades, with concurrent decrease in mortality. However, we present a case of a patient with a grade V liver laceration, in whom a rare portacaval shunt was also present. In the setting of this rare injury, the radiologist will likely be the first person to recognize and categorize a severe complication, which may indicate the need for a fundamental change in patient management. PMID:24421924

Spence, Susanna C; Strobel, Nathaniel HP; Beckmann, Nicholas M; Kumaravel, Manickam

2013-01-01

306

Intrahepatic portosystemic venous shunt: successful embolization using the Amplatzer Vascular Plug II.  

PubMed

A 67-year-old woman presented with memory impairment and behavioral changes. Brain MRI indicated hepatic encephalopathy. Abdominal CT scans revealed an intrahepatic portosystemic venous shunt that consisted of two shunt tracts to the aneurysmal sac that communicated directly with the right hepatic vein. The large tract was successfully occluded by embolization using the newly available AMPLATZERTM Vascular Plug II and the small tract was occluded by using coils. The patient's symptoms disappeared after shunt closure and she remained free of recurrence at the 3-month follow-up evaluation. PMID:23118586

Lee, Young-ju; Shin, Byung Seok; Lee, In Ho; Ohm, Joon Young; Lee, Byung-seok; Ahn, Moonsang; Kim, Ho Jun

2012-11-01

307

Transjugular intrahepatic portosystemic shunt flow reduction with adjustable polytetrafluoroethylene-covered balloon-expandable stents.  

PubMed

Creation of a transjugular intrahepatic portosystemic shunt (TIPS) can effectively treat complications of portal hypertension, but excessive shunting can cause life-threatening hepatic encephalopathy and hepatic insufficiency. The present report describes a novel technique that allows for controlled and adjustable flow reduction through the TIPS via partial closure of the shunt with a balloon-mounted covered stent. The method results in clinical improvement of hepatic encephalopathy and hepatic insufficiency and immediate increase in the portosystemic pressure gradient. However, among the four patients described herein, survival beyond 1 year was seen in only one, who underwent liver transplantation after TIPS reduction. PMID:19497763

Kroma, Ghazwan; Lopera, Jorge; Cura, Marco; Suri, Rajeev; El-Merhi, Fadi; Reading, Jerad

2009-07-01

308

Thoratec HeartMate II(®) left ventricular assist device implantation in patient with patent ventriculoperitoneal shunt.  

PubMed

We report a case of HeartMate II(®) left ventricular assist device (LVAD) implantation as a destination therapy in a patient with a patent ventriculoperitoneal (VP) shunt after being suffered from subarachnoid hemorrhage. Because the patient's VP shunt was running through her right anterior chest and abdominal wall, a driveline exit site was selected in her left upper quadrant to avoid unnecessary perioperative complication in relation to the patent VP shunt tube. Tailored driveline placement was a key element of this LVAD implantation in this already sick patient with multiple comorbidities. PMID:22293312

Yamane, Kentaro; Bogar, Linda J; Tabata, Shigeki; Hirose, Hitoshi

2012-08-20

309

Intrahepatic Portosystemic Venous Shunt: Successful Embolization Using the Amplatzer Vascular Plug II  

PubMed Central

A 67-year-old woman presented with memory impairment and behavioral changes. Brain MRI indicated hepatic encephalopathy. Abdominal CT scans revealed an intrahepatic portosystemic venous shunt that consisted of two shunt tracts to the aneurysmal sac that communicated directly with the right hepatic vein. The large tract was successfully occluded by embolization using the newly available AMPLATZERTM Vascular Plug II and the small tract was occluded by using coils. The patient's symptoms disappeared after shunt closure and she remained free of recurrence at the 3-month follow-up evaluation. PMID:23118586

Lee, Young-ju; Lee, In Ho; Ohm, Joon Young; Lee, Byung-seok; Ahn, Moonsang; Kim, Ho Jun

2012-01-01

310

Congenital hepatic arteriovenous fistula with intrahepatic portosystemic shunt and aortic stenosis in a dog.  

PubMed

Examination of a 2-month-old male golden retriever presented to the hospital revealed malnutrition, ascites, cardiac murmur and hyperammonemia. Identification of subaortic stenosis and hepatic arteriovenous fistula was made through ultrasonography and angiocardiography. In addition, intrasurgical mesenteric portography showed an intrahepatic portosystemic shunt. The dog did not show portal hypertension and secondary multiple extrahepatic portosystemic shunts. Surgical correction was attempted after medical treatment. The hepatic artery branch which was connected to the hepatic arteriovenous fistula was separated, and completely ligated using silk ligature. However, the separation of the intrahepatic shunt blood vessel was unsuccessful and the dog died 15 hr postoperatively. PMID:15107561

Koide, Kazuyoshi; Koide, Yukiko; Wada, Yasuhiro; Nakaniwa, Shigeki; Yamane, Yoshihisa

2004-03-01

311

Congenital portosystemic venous shunt in a preterm Rh-isoimmunized infant.  

PubMed

The authors report a preterm infant with Rh-isoimmunization, who had persistent hepato-splenomegaly with conjugated hyperbilirubinemia, transaminitis, and hyperammonemia. Ultrasound abdomen revealed an intrahepatic portosystemic venous shunt (PSVS). The child was managed conservatively. On follow up at 2.4 y of age, the child is having normal growth and development, but with persisting shunt. Severe Rh-isoimmunisation in a neonate can sometimes share some of the features of congenital PSVS and delay the diagnosis of the latter. The index case had shunt ratio >80 % during the neonatal period but did not require any intervention. PMID:23389350

Thukral, Anu; Arora, Kamaldeep; Das, Rashmi Ranjan; Arora, Arundeep; Gamanagatti, Shivanand; Agarwal, Ramesh K

2013-12-01

312

Failure of peritoneal and gallbladder shunts in a child with craniopharyngioma  

PubMed Central

A 1-year-old girl with craniopharyngioma required external drainage of 40-50 mL/h of cerebrospinal fluid (CSF) after biopsy and cyst fenestration. She developed CSF ascites following insertion of a ventriculoperitoneal (VP) shunt and a distended painful gallbladder following ventriculogallbladder shunt insertion. Revision to a ventriculoatrial shunt was required. This is the first time a craniopharyngioma has been reported to cause increased CSF production. The potential mechanisms of CSF overproduction and the difficulties managing the large volume of CSF in a young child are discussed. PMID:24470818

Woodfield, Julie; Magdum, Shailendra

2013-01-01

313

An interesting case of screen-detected breast cancer encasing a ventriculoperitoneal shunt  

PubMed Central

A 67-year-old woman was diagnosed with a breast cancer via screening encasing the ventriculoperitoneal shunt. Triple assessment including MRI scan of the breast confirmed the presence of a breast mass and the tubing of the ventriculoperitoneal shunt was running directly through the mass. She underwent wide local excision of the breast cancer as well as rerouting of VP shunt as a joint procedure with the neurosurgery team and recovered uneventfully. This is a very rare and an interesting case and required management involving a different specialty. PMID:23349174

Jain, Yogesh Kumar; Kokan, Jalal S

2013-01-01

314

Lp regularization for early gate fluorescence molecular tomography  

PubMed Central

Time domain fluorescence molecular tomography (TD-FMT) provides a unique dataset for enhanced quantification and spatial resolution. The time-gate dataset can be divided into two temporal groups around the maximum counts gate, which are early gates and late gates. It is well established that early gates allow for improved spatial resolution and late gates are essential for fluorophore unmixing and concentration quantification. However, the inverse problem of FMT is ill-posed and typically underdetermined, which makes image reconstruction highly susceptible to data noise. More specifically, photon counts are inherently very low at early gates due to high absorption and scattering of tissue, resulting in a low signal-to-noise ratio and unstable reconstructions. In this work, an Lp regularization-based reconstruction algorithm was developed and tested with our wide-field mesh-based Monte Carlo simulation strategy. We compared the early time-gate reconstructions obtained with the different p (p ? {1/16, 1/8, 1/4, 1/3, 1/2, 1, 2}) from a synthetic murine model simulating the fluorophore uptake in the kidneys and preclinical data. The results from a 3D mouse atlas and a mouse experiment show that our L1/4 regularization methods give the best performance for early time gates reconstructions. PMID:25121675

Zhao, Lingling; Yang, He; Cong, Wenxiang; Wang, Ge; Intes, Xavier

2014-01-01

315

75 FR 29466 - Airworthiness Directives; Gulfstream Aerospace LP (Type Certificate Previously Held by Israel...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Gulfstream Aerospace LP (Type Certificate Previously Held by Israel Aircraft Industries, Ltd.) Model Gulfstream G150 Airplanes...12866, the Regulatory Flexibility Act, or DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979)....

2010-05-26

316

77 FR 38128 - Withdrawal of TORP Terminal LP, Bienville Offshore Energy Terminal Liquefied Natural Gas (LNG...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Terminal LP, Bienville Offshore Energy Terminal Liquefied Natural Gas (LNG) Deepwater Port Application AGENCY: Maritime...construct, and operate a deepwater port for a liquefied natural gas deepwater port facility, located...

2012-06-26

317

78 FR 69078 - Houston Pipe Line Company LP; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...2013, Houston Pipe Line Company LP (HPL), 1300 Main Street, Houston, Texas 77002...Reynosa, State of Tamaulipas. Furthermore, HPL requests that the Commission issue a Presidential Permit authorizing HPL to site, construct, operate, and...

2013-11-18

318

78 FR 38306 - Pacific Connector Gas Pipeline, LP; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...000 Dekatherms per day of natural gas to the Jordan Cove LNG Export Terminal being developed by Jordan Cove Energy Project, L.P. that separately...June 8, 2012, the Commission staff granted Jordan Cove's request to utilize the...

2013-06-26

319

Lp-PLA2 inhibitory activities of fatty acid glycerols isolated from Saururus chinensis roots.  

PubMed

(R)-Glycerol-monolinoleate 4 and (R)-glycerol-monostearate 5 were isolated from the ethyl acetate extracts of Saururus chinensis roots and (R)- or (S)-fatty acid glycerols 4 and 5 were synthesized for confirming their structures and evaluating their inhibitory activities against Lp-PLA(2). The (R)-4 and (S)-4 exhibited Lp-PLA(2) inhibitory activities with IC(50) values of 45.0 and 52.0 microM, respectively. PMID:15961310

Lee, Woo Song; Kim, Mi Jeong; Beck, Young-Il; Park, Yong-Dae; Jeong, Tae-Sook

2005-08-01

320

Transjugular intrahepatic portosystemic stent-shunt: technical factors and new developments.  

PubMed

The introduction of expandable metal stents in the mid 1980s led to the development of transjugular intrahepatic portosystemic stent-shunt (TIPSS) as we know it today. Short-lived detrimental effects on the hyperdynamic circulation in cirrhosis accompany the acute reduction in portal pressure following TIPSS creation. Caution is needed in patients with cardiac dysfunction or pulmonary hypertension. With increasing expertise and careful patient selection, fatal procedural complications are rare and TIPSS can even be safely used as a bridge to liver transplantation. Shunt insufficiency and hepatic encephalopathy are more common following TIPSS. Currently, however, novel approaches to tackling both these limitations exist. These include the combination of uncovered TIPSS with variceal band ligation, and the introduction of polytetrafluoroethylene covered stents. Despite the lack of controlled studies, covered stents are now widely used and have the potential to drastically reduce shunt insufficiency, the need for long-term shunt surveillance and even hepatic encephalopathy. PMID:17033430

Tripathi, Dhiraj; Redhead, Doris

2006-11-01

321

Intrapulmonary shunting in the biliary atresia/polysplenia syndrome: reversal after liver transplantation.  

PubMed Central

One hundred and seventy three children, including 93 with biliary atresia, received liver grafts at Addenbrooke's Hospital between 1983 and 1993. Of these, only seven developed cyanosis due to intrapulmonary shunting as a complication of their liver disease, and all seven of these had the biliary atresia/polysplenia syndrome. Intrapulmonary shunting was confirmed by a radioisotope scan in four children. Only one child with the syndrome did not have cyanosis when undergoing transplantation. Seven of the eight children are alive 6-54 months after transplantation, with normal pulmonary and hepatic function. Cyanosis recurred in one child who developed chronic rejection with liver failure. In conclusion: (a) there is a strong association between the biliary atresia/polysplenia syndrome and cyanosis due to intrapulmonary shunting; (b) intrapulmonary shunting is fully reversible after successful liver transplantation; and (c) cyanosis, once present, is progressive, and these children should be considered for liver transplantation as soon as it occurs. PMID:8048820

Fewtrell, M S; Noble-Jamieson, G; Revell, S; Valente, J; Friend, P; Johnston, P; Rasmussen, A; Jamieson, N; Calne, R Y; Barnes, N D

1994-01-01

322

Noninvasive prediction of shunt operation outcome in idiopathic normal pressure hydrocephalus.  

PubMed

Idiopathic normal pressure hydrocephalus (iNPH) is a syndrome characterized by gait disturbance, cognitive deterioration and urinary incontinence in elderly individuals. These symptoms can be improved by shunt operation in some but not all patients. Therefore, discovering predictive factors for the surgical outcome is of great clinical importance. We used normalized power variance (NPV) of electroencephalography (EEG) waves, a sensitive measure of the instability of cortical electrical activity, and found significantly higher NPV in beta frequency band at the right fronto-temporo-occipital electrodes (Fp2, T4 and O2) in shunt responders compared to non-responders. By utilizing these differences, we were able to correctly identify responders and non-responders to shunt operation with a positive predictive value of 80% and a negative predictive value of 88%. Our findings indicate that NPV can be useful in noninvasively predicting the clinical outcome of shunt operation in patients with iNPH. PMID:25585705

Aoki, Yasunori; Kazui, Hiroaki; Tanaka, Toshihisa; Ishii, Ryouhei; Wada, Tamiki; Ikeda, Shunichiro; Hata, Masahiro; Canuet, Leonides; Katsimichas, Themistoklis; Musha, Toshimitsu; Matsuzaki, Haruyasu; Imajo, Kaoru; Kanemoto, Hideki; Yoshida, Tetsuhiko; Nomura, Keiko; Yoshiyama, Kenji; Iwase, Masao; Takeda, Masatoshi

2015-01-01

323

Congenital intrahepatic portosystemic venous shunt presenting with paraparesis as the initial symptom.  

PubMed

An 85-year-old woman was hospitalized with rapidly progressive paraparesis without altered consciousness, although she was not definitively diagnosed. She developed acute drowsiness and disorientation several days later. An intrahepatic portosystemic venous shunt (IPSVS) was observed on enhanced computed tomography, and hyperammonemia suggested leakage of neurotoxins from the shunt as the etiology of the patient's symptoms. Her neurological symptoms and hyperammonemia improved following transcatheter shunt embolization. We diagnosed her with hepatic myelopathy, which is a rare complication of liver cirrhosis and portosystemic venous shunts. Hepatic myelopathy resulting from a congenital IPSVS has not been previously reported. A diagnosis of hepatic myelopathy should be ruled out in diagnostically difficult cases of paraparesis. PMID:24190148

Torigoe, Masataka; Maeshima, Keisuke; Takeshita, Yasushi

2013-01-01

324

Transvenous coil embolisation for the treatment of single congenital portosystemic shunts in six dogs.  

PubMed

This article describes the treatment of single congenital portosystemic shunts (CPSs) (intrahepatic and extrahepatic) using an interventional radiology technique involving embolisation of anomalous vessels with percutaneous coils. Briefly, a multipurpose catheter was introduced into the caudal vena cava and then into the portosystemic shunt. An autoexpandable stent was placed in the caudal vena cava, next to the shunt, in order to avoid coil migrations, and a cobra-like vascular catheter was used to pass through the stent and to place the coils in the shunt. This technique was used for treatment of CPS in six dogs. The results indicate that percutaneous embolisation of a CPS using coils, a less invasive technique than the traditional surgical technique, may result in complete closure of the anomalous vessel without development of portal hypertension. PMID:17466545

Bussadori, Roberto; Bussadori, Claudio; Millán, Lorena; Costilla, Serafín; Rodríguez-Altónaga, José Antonio; Orden, María Asunción; Gonzalo-Orden, José Manuel

2008-05-01

325

Clinical experience with silicone rubber grafts as shunts in portal hypertension.  

PubMed

We report the use of a woven silicone rubber graft as an alternative prosthesis for a shunt in 8 patients with portal hypertension. Four patients were operated on as emergencies and 4 electively. In 4 cases the graft was used as a standard mesocaval H graft, in 2 as a portocaval H graft and in 2 cases it was used to simplify the Warren selective distal splenorenal shunt. The material has properties which make it a superior graft to existing prostheses and autogenous vein. Our results confirm the experience of others, that the poor risk patients do badly whatever form of shunt is performed, and of those who survive, the total portal shunt carries the risk of postoperative encephalopathy. PMID:678776

Parr, D C; Hopkinson, B R

1978-08-01

326

Noninvasive prediction of shunt operation outcome in idiopathic normal pressure hydrocephalus  

PubMed Central

Idiopathic normal pressure hydrocephalus (iNPH) is a syndrome characterized by gait disturbance, cognitive deterioration and urinary incontinence in elderly individuals. These symptoms can be improved by shunt operation in some but not all patients. Therefore, discovering predictive factors for the surgical outcome is of great clinical importance. We used normalized power variance (NPV) of electroencephalography (EEG) waves, a sensitive measure of the instability of cortical electrical activity, and found significantly higher NPV in beta frequency band at the right fronto-temporo-occipital electrodes (Fp2, T4 and O2) in shunt responders compared to non-responders. By utilizing these differences, we were able to correctly identify responders and non-responders to shunt operation with a positive predictive value of 80% and a negative predictive value of 88%. Our findings indicate that NPV can be useful in noninvasively predicting the clinical outcome of shunt operation in patients with iNPH. PMID:25585705

Aoki, Yasunori; Kazui, Hiroaki; Tanaka, Toshihisa; Ishii, Ryouhei; Wada, Tamiki; Ikeda, Shunichiro; Hata, Masahiro; Canuet, Leonides; Katsimichas, Themistoklis; Musha, Toshimitsu; Matsuzaki, Haruyasu; Imajo, Kaoru; Kanemoto, Hideki; Yoshida, Tetsuhiko; Nomura, Keiko; Yoshiyama, Kenji; Iwase, Masao; Takeda, Masatoshi

2015-01-01

327

Lp(a) is not associated with diabetes but affects fibrinolysis and clot structure ex vivo.  

PubMed

Lipoprotein (a) [Lp(a)] is a low density lipoprotein (LDL) with one apolipoprotein (a) molecule bound to the apolipoprotein B-100 of LDL. Lp(a) is an independent risk factor for cardiovascular disease (CVD). However, the relationship of Lp(a) to diabetes and metabolic syndrome, both known for increased CVD risk, is controversial. In a population based study on type two diabetes mellitus (T2DM) development in women, Lp(a) plasma levels showed the well known skewed distribution without any relation to diabetes or impaired glucose tolerance. A modified clot lysis assay on a subset of 274 subjects showed significantly increased clot lysis times in T2DM subjects, despite inhibition of PAI-1 and TAFI. Lp(a) plasma levels significantly increased the maximal peak height of the clot lysis curve, indicating a change in clot structure. In this study Lp(a) is not related to the development of T2DM but may affect clot structure ex vivo without a prolongation of the clot lysis time. PMID:24937703

Månsson, Marianne; Kalies, Inge; Bergström, Göran; Schmidt, Caroline; Legnehed, Anne; Hultén, Lillemor Mattsson; Amrot-Fors, Lena; Gustafsson, David; Knecht, Wolfgang

2014-01-01

328

Lp(a) is not associated with diabetes but affects fibrinolysis and clot structure ex vivo  

PubMed Central

Lipoprotein (a) [Lp(a)] is a low density lipoprotein (LDL) with one apolipoprotein (a) molecule bound to the apolipoprotein B-100 of LDL. Lp(a) is an independent risk factor for cardiovascular disease (CVD). However, the relationship of Lp(a) to diabetes and metabolic syndrome, both known for increased CVD risk, is controversial. In a population based study on type two diabetes mellitus (T2DM) development in women, Lp(a) plasma levels showed the well known skewed distribution without any relation to diabetes or impaired glucose tolerance. A modified clot lysis assay on a subset of 274 subjects showed significantly increased clot lysis times in T2DM subjects, despite inhibition of PAI-1 and TAFI. Lp(a) plasma levels significantly increased the maximal peak height of the clot lysis curve, indicating a change in clot structure. In this study Lp(a) is not related to the development of T2DM but may affect clot structure ex vivo without a prolongation of the clot lysis time. PMID:24937703

Månsson, Marianne; Kalies, Inge; Bergström, Göran; Schmidt, Caroline; Legnehed, Anne; Hultén, Lillemor Mattsson; Amrot-Fors, Lena; Gustafsson, David; Knecht, Wolfgang

2014-01-01

329

Capacity Release by Shunt Capacitor Placement on Distribution Feeders: A New Voltage-Dependent Model  

Microsoft Academic Search

A new voltage-dependent methodology for shunt-capacitor compensation of primary distribution feeders is presented. A generalized computer-based procedure is described for optimally sizing and placing any specified number of fixed shunt capacitors while accounting for voltage variation along the feeder. The procedure is applied to a physically-existing feeder with known P, Q loads to yield results for capacity release exactly comparable

J. J. Grainger; S. H. Lee

1982-01-01

330

Superconducting FCL using a combined inducted magnetic field trigger and shunt coil  

DOEpatents

A single trigger/shunt coil is utilized for combined induced magnetic field triggering and shunt impedance. The single coil connected in parallel with the high temperature superconducting element, is designed to generate a circulating current in the parallel circuit during normal operation to aid triggering the high temperature superconducting element to quench in the event of a fault. The circulating current is generated by an induced voltage in the coil, when the system current flows through the high temperature superconducting element.

Tekletsadik, Kasegn D. (Rexford, NY)

2007-10-16

331

Large spontaneous intrahepatic portal-systemic venous shunt treated with coil and Amplatzer vascular plug embolization.  

PubMed

Spontaneous intrahepatic portal-systemic shunts are rare and can lead to significant encephalopathy. If intervention is recommended, transcatheter embolization is preferred. Various embolization techniques have been described using a wide range of embolization materials. In this report, the authors describe a useful embolization technique for managing a complex, large type 3 spontaneous intrahepatic portal-systemic shunt using Nester coils and Amplatzer vascular plugs through both percutaneous systemic and transhepatic approaches. PMID:22886187

Power, Adam H; Bjarnason, Haraldur

2012-06-01

332

Cavoatrial shunt: a graft salvage procedure for suprahepatic caval anastomosis obstruction after liver transplantation.  

PubMed

A liver transplant recipient developed the Budd-Chiari syndrome because of an obstruction of the suprahepatic inferior vena cava anastomosis. Percutaneous balloon dilatation angioplasty was not feasible. On exploration, dense retrohepatic fibrotic reaction was observed. The patient underwent successful retrohepatic cavoatrial shunt placement by means of a 16-mm, ring-enforced polytetrafluoroethylene graft. We conclude that this shunt should be considered an additional graft salvage procedure for this complication. PMID:9563965

Eid, A; Rahamimov, R; Ilan, Y; Tur-Kaspa, R; Berlatzky, Y

1998-05-01

333

Increased incidence of glomerulonephritis following spleno-renal shunt surgery in non-cirrhotic portal fibrosis  

Microsoft Academic Search

Increased incidence of glomerulonephritis following spleno-renal shunt surgery in non-cirrhotic portal fibrosis. In a prospective study of 200 non-cirrhotic portal fibrosis (NCPF) patients, 7% had mild proteinuria and their renal biopsies showed mild mesangial proliferative glomerulonephritis (mes-PGN). The remaining 93% biopsies were normal. However, following the insertion of a spleno-renal shunt (SRS) for portal hypertension 32% of these patients developed

Suresh C Dash; Uday N Bhuyan; Amit K Dinda; Sanjiv Saxena; Sanjay K Agarwal; Suresh C Tiwari; Samiran Nundy

1997-01-01

334

Spontaneous expectoration of a Blalock-Taussig shunt a decade after operation  

PubMed Central

An eleven-year-old boy expectorated a foreign body in cough that was identified as the prosthetic graft used for a Blalock-Taussig shunt. The shunt procedure was done 10 years earlier, and a definitive repair for tetralogy of Fallot was done a year later. He had no other symptoms, and a computed tomography (CT) angiogram did not reveal any other significant anomaly. The reason for this extremely rare event is unclear.

Kothari, Shyam S; Murugan, Madhan Kumar; Chowdhury, Ujjwal Kumar

2015-01-01

335

Accuracy of the transpulmonary ultrasound dilution method for detection of small anatomic shunts.  

PubMed

The purpose of this study was to investigate the qualitative and quantitative accuracy of transpulmonary ultrasound dilution (UD) (COstatus™, Transonic Systems) for the detection of small anatomic shunts. It was a prospective, observational study in a multi-disciplinary pediatric intensive care unit. Seventy-three critically ill children (67 post cardiac surgery), with a median (IQR) age of 10 (3-50.3) months and a median (IQR) weight of 8 (3.43-13) kg were enrolled. Ultrasound dilution (UD) measurements were performed on patients within 1 h of undergoing two-dimensional echocardiography, which was used as the comparator technique. Shunt was diagnosed by characteristic changes on the UD curve shape, and was considered "test-positive" only if two or more measurements suggested the presence of the shunt. The UD technology also provided an estimate of pulmonary to systemic blood flow ratio (Qp:Qs). 12/73 (16.4 %) patients had a shunt identified by both UD and echocardiography. The overall accuracy (95 % CI) was 86.1 % (75.6-96.6 %), with a sensitivity of 85.7 % (57.2-98.2 %) and specificity of 86.4 % (75.0-94.0 %). The estimated Qp:Qs ranged from 0.7 to 1.4, which was consistent qualitatively with the echocardiographic findings on color flow doppler. Shunt was detected by UD alone in eight children; six of these had clinical conditions known to compromise dilution curve analysis (valve regurgitation, asymmetric pulmonary blood flow). Shunt was detected by echocardiography alone in two children; in both cases the shunt was tiny. UD is an accurate method for the detection of small anatomical shunts, both qualitatively and quantitatively. PMID:25240251

Saxena, R; Krivitski, N; Peacock, K; Durward, A; Simpson, J M; Tibby, S M

2014-09-21

336

Multiple PZT transducers implemented with multiple-mode piezoelectric shunting for passive vibration damping  

NASA Astrophysics Data System (ADS)

In an earlier paper we reported a method for multiple-mode shunt-damping of structural vibration modes. It was successfully demonstrated in experiments on a two-wing cantilever beam to reduce three structural vibration modes simultaneously using a single piezoelectric PZT transducer. This multiple-mode shunting method is particularly useful for reduction of several vibration modes on structures that are limited in surface area and must be lightweight. To obtain a better overall damping performance for some structures, we have extended this shunting technique by employing multiple PZT transducers; each is implemented with a multiple-mode shunt circuit. This paper reports the reason why multiple transducers are needed and how we design the multiple-mode shunt circuits for them. This is described with experiments performed on two structures: one, a simple cantilever beam and the other, a cut-out panel from an F-15 fighter aircraft. Both of the structures are bonded with several PZT transducers implemented with multiple-mode shunt circuits. In the cantilever beam structure, we show the advantage of using a different transducer for controlling modes that are otherwise not controllable with the first transducer alone. For the F-15 panel, five PZT transducers were bonded on the inner surface of the panel. During the shunting experiment, the panel was excited with an acoustic load. We report how we determined the locations and the number of the transducers, and how we designed and implemented them with multiple-mode shunt circuits to control the two high-structural-vibration modes. Detailed experimental results are presented.

Wu, Shu-yau

1999-06-01

337

Two-year outcome following transjugular intrahepatic portosystemic shunt for variceal bleeding: Results in 90 patients  

Microsoft Academic Search

Background\\/Aims: Transjugular intrahepatic portosystemic shunt (TIPS) is a new therapy for variceal bleeding. Immediate technical and short-term clinical results have been reported. This study was undertaken to evaluate mid-term outcome after TIPS in patients who successfully underwent the procedure for variceal bleeding. Methods: Ninety patients were followed up prospectively by clinical examination and radiological shunt evaluation including Doppler sonography and

Jeanne M. Laberge; Kenneth A. Somberg; John R. Lake; Roy L. Gordon; Robert K. Kerlan; Nancy L. Ascher; John P. Roberts; Margaret M. Simor; Catherine A. Doherty; Judith Hahn; Peter BachettiI; Ernest J. Ring

1995-01-01

338

Evaluation of Microbial Bacterial and Fungal Diversity in Cerebrospinal Fluid Shunt Infection  

PubMed Central

Background Cerebrospinal fluid shunt infection can be recalcitrant. Recurrence is common despite appropriate therapy for the pathogens identified by culture. Improved diagnostic and therapeutic approaches are required, and culture-independent molecular approaches to cerebrospinal fluid shunt infections have not been described. Objectives To identify the bacteria and fungi present in cerebrospinal fluid from children with cerebrospinal fluid shunt infection using a high-throughput sequencing approach, and to compare those results to those from negative controls and conventional culture. Methods This descriptive study included eight children ?18 years old undergoing treatment for culture-identified cerebrospinal fluid shunt infection. After routine aerobic culture of each cerebrospinal fluid sample, deoxyribonucleic acid (DNA) extraction was followed by amplification of the bacterial 16S rRNA gene and the fungal ITS DNA region tag-encoded FLX-Titanium amplicon pyrosequencing and microbial phylogenetic analysis. Results The microbiota analyses for the initial cerebrospinal fluid samples from all eight infections identified a variety of bacteria and fungi, many of which did not grow in conventional culture. Detection by conventional culture did not predict the relative abundance of an organism by pyrosequencing, but in all cases, at least one bacterial taxon was detected by both conventional culture and pyrosequencing. Individual bacterial species fluctuated in relative abundance but remained above the limits of detection during infection treatment. Conclusions Numerous bacterial and fungal organisms were detected in these cerebrospinal fluid shunt infections, even during and after treatment, indicating diverse and recalcitrant shunt microbiota. In evaluating cerebrospinal fluid shunt infection, fungal and anaerobic bacterial cultures should be considered in addition to aerobic bacterial cultures, and culture-independent approaches offer a promising alternative diagnostic approach. More effective treatment of cerebrospinal fluid shunt infections is needed to reduce unacceptably high rates of reinfection, and this work suggests that one effective strategy may be reduction of the diverse microbiota present in infection. PMID:24421877

Simon, Tamara D.; Pope, Christopher E.; Browd, Samuel R.; Ojemann, Jeffrey G.; Riva-Cambrin, Jay; Mayer-Hamblett, Nicole; Rosenfeld, Margaret; Zerr, Danielle M.; Hoffman, Lucas

2014-01-01

339

Circular shunt in a pulmonary artery to right atrial tunnel, an anomaly unreported so far  

PubMed Central

While aortico-right atrial tunnels with left to right shunt from aorta to right atrium are reported widely, pulmonary artery to right atrial tunnels have not been described so far. Such a tunnel will lead to a circular shunt with a recirculation of blood in the right sided cardiac chambers repeatedly bypassing the pulmonary capillary bed. This newly described pulmonary artery to right atrial tunnel was closed nonsurgically with a duct occluder after angiographic delineation. PMID:24987267

Singhi, Anil Kumar; Sivakumar, Kothandam

2014-01-01

340

The collateral caval shunt as an alternative to classical shunt procedures in patients with recurrent duodenal varices and extrahepatic portal vein thrombosis.  

PubMed

Upper gastrointestinal bleeding episodes from variceal structures are severe complications in patients with portal hypertension. Endoscopic sclerotherapy and variceal ligation are the treatment options preferred for upper variceal bleeding owing to extrahepatic portal hypertension due to portal vein thrombosis (PVT). Recurrent duodenal variceal bleeding in non-cirrhotic patients with diffuse porto-splenic vein thrombosis and subsequent portal cavernous transformation represent a clinical challenge if classic shunt surgery is not possible or suitable.In this study, we represent a case of recurrent bleeding of duodenal varices in a non-cirrhotic patient with cavernous transformation of the portal vein that was successfully treated with a collateral caval shunt operation. PMID:24965047

Hau, Hans Michael; Fellmer, Peter; Schoenberg, Markus B; Schmelzle, Moritz; Morgul, Mehmet Haluk; Krenzien, Felix; Wiltberger, Georg; Hoffmeister, Albrecht; Jonas, Sven

2014-01-01

341

The collateral caval shunt as an alternative to classical shunt procedures in patients with recurrent duodenal varices and extrahepatic portal vein thrombosis  

PubMed Central

Upper gastrointestinal bleeding episodes from variceal structures are severe complications in patients with portal hypertension. Endoscopic sclerotherapy and variceal ligation are the treatment options preferred for upper variceal bleeding owing to extrahepatic portal hypertension due to portal vein thrombosis (PVT). Recurrent duodenal variceal bleeding in non-cirrhotic patients with diffuse porto-splenic vein thrombosis and subsequent portal cavernous transformation represent a clinical challenge if classic shunt surgery is not possible or suitable. In this study, we represent a case of recurrent bleeding of duodenal varices in a non-cirrhotic patient with cavernous transformation of the portal vein that was successfully treated with a collateral caval shunt operation. PMID:24965047

2014-01-01

342

Unusual shunt for symptomatic portal vein thrombosis after liver transplantation - Clatworthy revisited.  

PubMed

PV thrombosis is not an uncommon occurrence following pediatric LT. Symptomatic PHT following PV thrombosis is treated medically, surgical portosystemic shunting (mesorex, splenorenal, and mesocaval) being reserved for refractory cases. A 10-yr-old boy suffered recurrent malena and hemorrhagic shock because of chronic PV thrombosis following LT nine yr ago (1999). Extensive work-up failed to localize the bleeding source. The liver function remained normal. Initial attempts at surgical shunts failed owing to thrombosis (mesocaval 2001, splenorenal, inferior mesenteric-left renal vein, splenic-left external iliac vein 2008). In this situation, we performed a Clatworthy shunt by anastomosing the divided lower end of the LCIV to the side of SMV. There was a single, large caliber anastomosis. Post-operatively, the malena stopped completely, and clinically, there was no lower limb edema or encephalopathy. Doppler USG revealed persistence of hepatopetal flow within the portal collaterals. Follow-up at two yr reveals stable hepatic function with a patent shunt. To the best of our knowledge, we are not aware of a Clatworthy shunt being performed in a transplant setting. We reviewed the literature pertaining to this shunt in non-transplant patients with PHT. PMID:21834802

Mali, V P; Robless, P A; Aw, M; Loh, D L; Quak, S H; Prabhakaran, K

2012-06-01

343

Portosystemic encephalopathy due to mesoiliac shunt in a patient without cirrhosis.  

PubMed

Hepatic encephalopathy most commonly occurs in patients with cirrhosis and end-stage liver disease, however, the disorder can also occur in the presence of intrahepatic or extrahepatic shunts when the intrahepatic circulation is effectively bypassed. The majority of extrahepatic shunts described to date develop between a mesenteric vein and inferior vena cava. Herein we report a novel case of a superior mesenteric vein to left internal iliac vein shunt that led to hepatic encephalopathy in a 57-year-old woman with no apparent underlying liver disorder. The patient presented with confusion, disorientation, and hyperammonemia. Workup for parenchymal liver disease was negative and liver biopsy findings did not show significant liver disease. Magnetic resonance imaging revealed a serpiginous 1-cm-wide shunt that diverted superior mesenteric vein blood from the portal confluence to the left internal iliac vein. Surgical closure of the shunt led to marked improvement of the patient with the resolution of hepatic encephalopathy. This report is the first description of a portosystemic shunt, likely congenital, linking these 2 vessels resulting in clinically significant hepatic encephalopathy. The findings emphasize that abdominal and pelvic imaging should be considered in patients with signs of hepatic encephalopathy that have none to minimal hepatic disease. PMID:19636259

Ali, Sobia; Stolpen, Alan H; Schmidt, Warren N

2010-01-01

344

Novel therapy for non-cirrhotic hyperammonemia due to a spontaneous splenorenal shunt.  

PubMed

Spontaneous splenorenal shunts in the absence of cirrhosis have rarely been reported as a cause hyperammonemia with encephalopathy. Several closure techniques of such lesions have been described. Here we report a case of a patient with no history of liver disease who developed significant confusion. After an extensive workup, he was found to have hyperammonemia and encephalopathy due to formation of a spontaneous splenorenal shunt. There was no evidence of cirrhosis on biopsy or imaging and no portal hypertension when directly measured. The shunt was 18 mm and too large for embolization so the segment of the splenic vein between the portal vein and the shunt was occluded using an Amplatzer plug. Thus, the superior mesenteric flow was directed entirely to the liver. After interventional radiology closure of the shunt using this technique there was complete resolution of symptoms. The case represents the first report of a successful closure of splenorenal shunt via percutaneous embolization of the splenic vein with an amplatzer plug using a common femoral vein approach. PMID:25009405

Rogal, Shari S; Hu, Angela; Bandi, Rupal; Shaikh, Obaid

2014-07-01

345

Fatal intratumoral hemorrhage in tectal plate glioblastoma multiforme following ventriculoperitoneal shunt  

PubMed Central

Ventriculo-peritoneal (V-P) shunting is an accepted procedure before a direct approach to large tumors producing obstructive hydrocephalus. However, it has been associated with some complications. Intratumoral hemorrhage is an uncommon but fatal complication of V-P shunt insertion. The exact mechanism of this complication is unknown, but several mechanisms have been proposed including rapid lowering of intracranial pressure following V-P shunt placement or cerebrospinal fluid (CSF) drainage and sudden decrease in CSF volume and pressure after V-P shunting. We report an 8-year-old girl who presented with severe headache, double vision, and bilateral papilledema. Brain magnetic resonance imaging with and without gadolinium administration revealed a large tectal plate tumor compressing the aqueduct which caused hydrocephalus. Due to progressive decline in consciousness level, an emergency CSF diversion was planned and she underwent left side posterior parietal V-P shunt placement. Eight hours after V-P shunt insertion, she suddenly developed tonic-clonic seizures and collapsed into deep coma with dilated pupils and stopped breathing and died 1-day later. Histological examination of the autopsy specimen showed the tumor was a glioblastoma multiforme with massive intratumoral hemorrhage. The possible pathophysiological mechanisms of this fatal complication are discussed here and the pertinent literature is reviewed. It seems that endoscopic third ventriculostomy is the procedure of choice for CSF diversion in patients with tectal plate gliomas and decreases the occurrence of intratumoral hemorrhage. PMID:25250086

Khalatbari, Mahmoud Reza; Khalatbari, Sepehrdad; Moharamzad, Yashar

2014-01-01

346

Fatal intratumoral hemorrhage in tectal plate glioblastoma multiforme following ventriculoperitoneal shunt.  

PubMed

Ventriculo-peritoneal (V-P) shunting is an accepted procedure before a direct approach to large tumors producing obstructive hydrocephalus. However, it has been associated with some complications. Intratumoral hemorrhage is an uncommon but fatal complication of V-P shunt insertion. The exact mechanism of this complication is unknown, but several mechanisms have been proposed including rapid lowering of intracranial pressure following V-P shunt placement or cerebrospinal fluid (CSF) drainage and sudden decrease in CSF volume and pressure after V-P shunting. We report an 8-year-old girl who presented with severe headache, double vision, and bilateral papilledema. Brain magnetic resonance imaging with and without gadolinium administration revealed a large tectal plate tumor compressing the aqueduct which caused hydrocephalus. Due to progressive decline in consciousness level, an emergency CSF diversion was planned and she underwent left side posterior parietal V-P shunt placement. Eight hours after V-P shunt insertion, she suddenly developed tonic-clonic seizures and collapsed into deep coma with dilated pupils and stopped breathing and died 1-day later. Histological examination of the autopsy specimen showed the tumor was a glioblastoma multiforme with massive intratumoral hemorrhage. The possible pathophysiological mechanisms of this fatal complication are discussed here and the pertinent literature is reviewed. It seems that endoscopic third ventriculostomy is the procedure of choice for CSF diversion in patients with tectal plate gliomas and decreases the occurrence of intratumoral hemorrhage. PMID:25250086

Khalatbari, Mahmoud Reza; Khalatbari, Sepehrdad; Moharamzad, Yashar

2014-05-01

347

Novel therapy for non-cirrhotic hyperammonemia due to a spontaneous splenorenal shunt  

PubMed Central

Spontaneous splenorenal shunts in the absence of cirrhosis have rarely been reported as a cause hyperammonemia with encephalopathy. Several closure techniques of such lesions have been described. Here we report a case of a patient with no history of liver disease who developed significant confusion. After an extensive workup, he was found to have hyperammonemia and encephalopathy due to formation of a spontaneous splenorenal shunt. There was no evidence of cirrhosis on biopsy or imaging and no portal hypertension when directly measured. The shunt was 18 mm and too large for embolization so the segment of the splenic vein between the portal vein and the shunt was occluded using an Amplatzer plug. Thus, the superior mesenteric flow was directed entirely to the liver. After interventional radiology closure of the shunt using this technique there was complete resolution of symptoms. The case represents the first report of a successful closure of splenorenal shunt via percutaneous embolization of the splenic vein with an amplatzer plug using a common femoral vein approach. PMID:25009405

Rogal, Shari S; Hu, Angela; Bandi, Rupal; Shaikh, Obaid

2014-01-01

348

Lactobacillus paracasei Lp6 favors immune modulation induced by allergoid treatment in ragweed sensitized mice.  

PubMed

It has been hypothesized that lactic acid bacteria (LAB) could be used as adjuvant for specific immunotherapy (SIT), as various studies conducted on humans and animals converge to define LAB as anti-Th2 modulators and Treg inducers. In the present study we evaluated the effects of LAB, in particular Lactobacillus paracasei Lp6 (Lp6), in a mouse model of ragweed (RW) allergy. Groups of Balb/c mice, experimentally sensitized towards ragweed, were treated by viable Lp6 or by RWallergoid with or without co-administration of Lp6. A control group was sham-sensitized with PBS and sham-treated with water and a group was sensitized with RW and treated with water. Serum IgE, RW-induced release of IFN-gamma, IL-4 and IL-10 from splenocytes and the frequency of CD4CD25 regulatory T cells (Tregs) expressing Foxp3 or IL-10 were evaluated in various groups. RW-allergoid treatment induced a reduction of serum IgE, with a decrease in RW-induced release of IL-4, and an increase in IL-10 and IFN-gamma, along with a significant change in the frequency of Tregs, both CD25+ and -. The joint RWallergoid+ Lp6 treatment induced the highest degree of suppression of allergen-driven IL-4, the greatest reduction of IL-4/IFN-gamma and IL-4/IL-10 ratios and the most significant increase of Foxp3 and IL-10 expressing Tregs. The study shows that Lp6 strengthens the immune modulation induced by allergoid-SIT in RW-sensitized mice, essentially characterized by a differential induction of Tregs associated to a reduction of IL-4; data converge to define a role of SIT adjuvant for Lp6. PMID:22230395

Petrarca, C; Lazzarin, F; Lanuti, P; Marchisio, M; Miscia, S; Rossi, C; Braga, M; Mistrello, G; Di Gioacchino, M

2011-01-01

349

Scaling of electromagnetic transducers for shunt damping and energy harvesting  

NASA Astrophysics Data System (ADS)

In order for an electromagnetic transducer to operate well as either a mechanical shunt damper or as a vibration energy harvester, it must have good electromechanical coupling. A simple two-port analysis is used to derive a non-dimensional measure of electromechanical coupling, which must be large compared with unity for efficient operation in both of these applications. The two-port parameters for an inertial electromagnetic transducer are derived, from which this non-dimensional coupling parameter can be evaluated. The largest value that this parameter takes is approximately equal to the square of the magnetic flux density times the length of wire in the field, divided by the mechanical damping times the electrical resistance. This parameter is found to be only of the order of one for voice coil devices that weigh approximately 1 kg, and so such devices are generally not efficient, within the definition used here, in either of these applications. The non-dimensional coupling parameter is found to scale in approximate proportion to the device's characteristic length, however, and so although miniaturised devices are less efficient, greater efficiency can be obtained with large devices, such as those used to control civil engineering structures.

Elliott, Stephen J.; Zilletti, Michele

2014-04-01

350

Hyperglucagonemia and hyperkinetic circulation after portocaval shunt in the rat  

SciTech Connect

The study was aimed at investigating whether increased portal venous inflow (PVI) after portocaval shunt (PCS) in the rat is the result of selective splanchnic vasodilatation or whether it is part of a generalized circulatory disturbance. Rats with PCS and sham-operated controls were studied 2 wk after surgery by measuring cardiac output (CO), PVI, and hepatic artery flow (HAF) with radioactive microspheres (V Cr and UC). Plasma glucagon (GL) was measured by radioimmunoassay. PCS rats had increased CO and reduced arterial pressure and total peripheral resistance. PVI was markedly increased, but this appeared to be part of a generalized circulatory disturbance, since when PVI is expressed as percent of CO no difference is observed between PCS and sham-operated rats, indicating the absence of a preferential splanchnic vasodilatation. GL increased after PCS, and significant correlations were observed between GL and CO and between GL and PVI. HAF increased after PCS but did not compensate the loss of portal flow, evidence by a lower total hepatic flow in PCS rats. These results suggest that PCS induces a hyperkinetic circulatory state in which increased PVI represents its splanchnic manifestation and that increased GL release may be in part responsible for these hemodynamic changes.

Kravetz, D.; Arderiu, M.; Bosch, J.; Fuster, J.; Visa, J.; Casamitjana, R.; Rodes, J.

1987-02-01

351

Transcatheter venous embolization of a massive hepatic arteriovenous shunt complicating hepatocellular carcinoma using an Amplatzer Vascular Plug  

Microsoft Academic Search

Arteriovenous (AV) shunts are relatively uncommon in the liver and usually associated with advanced hepatocellular carcinoma\\u000a (HCC). In patients with massive AV shunts complicating advanced HCC, transarterial chemoinfusion therapy is not effective\\u000a because chemotherapeutic agents go through the shunts and may cause systemic toxicity as well as decrease the chemotherapeutic\\u000a effects against the tumor. We report two cases of successful

Sun Ki Kim; Ho Jong Chun; Byung Gil Choi; Hae Giu Lee; Si Hyun Bae; Jong Young Choi

2011-01-01

352

Successful transcatheter closure of a congenital high-flow portosystemic venous shunt with the Amplatzer vascular plug II.  

PubMed

Congenital portosystemic venous shunt is extremely rare and should be treated. Advances in treatment techniques allow for patients to be treated safely. We present a 9-year-old boy with a large congenital portosystemic venous shunt. The shunt was occluded interventionally with the Amplatzer vascular plug II. Our case was unique with its clinical manifestation, the use of a 22-mm Amplatzer vascular plug II, and the presence of the patient's 1-year follow-up. PMID:23885056

Guneyli, Serkan; Cinar, Celal; Bozkaya, Halil; Parildar, Mustafa; Oran, Ismail; Akin, Yigit

2012-12-01

353

Comparison of transcranial Doppler ultrasound and transesophageal contrast echocardiography in the detection of interatrial right-to-left shunts.  

PubMed

Transesophageal contrast echocardiography is an effective but semiinvasive technique for the detection of interatrial right-to-left shunts. Transcranial Doppler ultrasound is an alternative noninvasive method, but may be limited by false-positive diagnoses due to intrapulmonary shunting. This study examined the accuracy of transcranial Doppler for the detection of shunt lesions. Transcranial Doppler of the right middle cerebral artery was performed simultaneously with transesophageal and transthoracic contrast echocardiography in 32 patients using agitated saline contrast during normal respiration and Valsalva. Transesophageal contrast echocardiography diagnosed an interatrial right-to-left shunt in 13 patients and intrapulmonary shunting in 6 patients. Transcranial Doppler identified all 13 interatrial right-to-left shunts and an intrapulmonary shunt in 3 of 6 patients. Absence of a shunt was confirmed by transcranial Doppler in 12 of 12 patients. Transcranial Doppler had a sensitivity of 100% (13 of 13), specificity of 100% (18 of 18) and accuracy of 100% (31 of 31) for prediction of an interatrial right-to-left shunt by transesophageal contrast echocardiography. In comparison, transthoracic contrast echocardiography had a sensitivity of 54% (7 of 13), specificity of 94% (17 of 18) and accuracy of 77% (24 of 31). Thus, transcranial Doppler is highly accurate for detection of an interatrial right-to-left shunt and not compromised by physiologic intrapulmonary shunts, whereas transthoracic contrast echocardiography lacks sensitivity. Transcranial Doppler may be useful as an alternative to transesophageal study, where the primary indication for transesophageal echocardiography is exclusion of an interatrial right-to-left shunt. PMID:1746433

Nemec, J J; Marwick, T H; Lorig, R J; Davison, M B; Chimowitz, M I; Litowitz, H; Salcedo, E E

1991-12-01

354

Critical Shunt-Induced Subdural Hematoma Treated with Combined Pressure-Programmable Valve Implantation and Endoscopic Third Ventriculostomy  

Microsoft Academic Search

The authors present 2 patients with VP shunt-induced subdural hematomas (SDH) treated with pressure-programmable valve implantation and endoscopic third ventriculostomies (TV). The first patient is an 11-year-old girl who developed a shunt-induced SDH. Revision of the shunt valve with a higher-pressure valve resulted in a prolonged deterioration of her consciousness. External ventricular drainage at low pressure led to clinical improvement.

Toru Fukuhara; Sarel J. Vorster; Mark G. Luciano

2000-01-01

355

Post-TIPS Hepatic Encephalopathy Treated by Occlusion Balloon-Assisted Retrograde Embolization of a Coexisting Spontaneous Splenorenal Shunt  

SciTech Connect

A 51-year-old man with posthepatitis cirrhosis underwent a transjugular intrahepatic portosystemic shunt (TIPS) for bleeding of recurrent esophageal varices. The patient had a coexisting, spontaneous, splenorenal shunt. He subsequently developed hepatic encephalopathy, presumably due to excessive portosystemic shunting. Since medical management resulted in no significant improvement, the splenorenal shunt was embolized from the jugular vein approach via renal vein access during temporary balloon occlusion. Within a few days, the patient's hepatic encephalopathy resolved. Twelve months later the patient showed no recurrence of encephalopathy and had maintained a patent TIPS.

Shioyama, Yasukazu; Matsueda, Kiyoshi; Horihata, Koushi; Kimura, Masashi [Department of Radiology, Central Hospital and Cancer Center of Ibaraki Prefecture, 6528 Koibuchi Tomobe-machi, Nishiibaraki-gun, Ibaraki, Japan 309-17 (Japan); Nishida, Norifumi; Kishi, Kazushi; Terada, Masaki; Sato, Morio; Yamada, Ryusaku [Department of Radiology, Wakayama Medical College, 27 7-bancho, Wakayama-shi, Wakayama, Japan 640 (Japan)

1996-11-15

356

Ventriculoperitoneal shunt and the need to remove a gallbladder: Time to definitely overcome the feeling that laparoscopic surgery is contraindicated  

PubMed Central

Since Baskin et al. reported the first documented case of failure of a laparoscopically-induced ventriculoperitoneal shunt (VP) in 1998, the cerebrospinal fluid shunt has been generally considered a relative contraindication to laparoscopy. Although the literature is limited there is a small body of evidence indicating that it is safe to perform laparoscopic surgery on these patients with routine anaesthetic monitoring. In this study we report the case of a laparoscopic cholecystectomy in the presence of a ventriculoperitoneal shunt. A review of the literature suggests that laparoscopic cholecystectomy can be safely performed in patients with a ventriculoperitoneal shunt. The only related contraindication should be if a catheter has recently been placed.

Cobianchi, Lorenzo; Dominioni, Tommaso; Filisetti, Claudia; Zonta, Sandro; Maestri, Marcello; Dionigi, Paolo; Alessiani, Mario

2014-01-01

357

T1-201 per rectum: A noninvasive method for evaluating portosystemic shunt  

SciTech Connect

Portosystemic shunt is one of the most important complications of liver cirrhosis. Unfortunately, current methods for detecting and quantifying this shunt are either non-specific or associated with significant morbidity. The aim of this work was to evaluate the clinical value of a new non-traumatic method which consisted of administrating T1-201 per rectum and monitoring the absorbed activity using a camera and a computer system. The method assumes that in the absence of portosystemic shunt, most of the absorbed activity will be fixed in the liver while in the presence of this shunt, some of the activity will be fixed in the myocardium. The ratio of heart to liver activity can therefore be used to evaluate the importance of the portosystemic shunt. 34 subjects have been studied. The ratio of heart to liver activity at the 25th minute after the tracer administration is higher in patients with liver cirrhosis (n=22, m=.9, s.d.=.37) than in patients with steatosis (n=10, m=.28, s.d.=.03). In two healthy subjects investigated the H/L ratio was .27 and .30. The reproducibility of the test was evaluated in 8 subjects and showed a good reproducibility (mean of difference =.03, range=.01 to .07). Patients with esophageal varices had always a high H/L ratio while some patients with liver cirrhosis without esophageal varices had also high H/L ratio, probably due to the presence of intrahepatic shunt. The authors' results showed the value of this new non-traumatic test for detecting and quantifying extra- as well as intrahepatic portosystematic shunt.

Verdickt, X.; Reding, P.; Tshiamala, P.; Ham, H.R.

1984-01-01

358

The Budd-Chiari syndrome. Treatment by mesenteric-systemic venous shunts.  

PubMed Central

Twelve patients with the Budd-Chiari syndrome have been managed surgically. Ten of the patients were female, two were male, with a mean age of 40 years. Three of the patients had polycythemia vera, two had pre-existing cirrhosis, one had ingested estrogens, one had an occult tumor, and in four there were no associated factors. Ten patients presented with ascites and two with bleeding esophageal varices. The diagnosis was confirmed in all 12 patients by liver biopsy and hepatic vein catheterization. Inferior vena cavography revealed the abdominal vena cava to be thrombosed in six patients. The superior mesenteric vein was used to decompress the congested liver in all 12 patients. In five patients, a mesocaval shunt (MCS) was performed and in seven patients, a mesoatrial shunt (MAS) was carried out. There were four hospital deaths (two MCS, two MAS). One late death (MAS) occurred from liver failure following shunt thrombosis. Two additional patients (one MCS, one MAS) re-developed ascites immediately following surgery and angiography revealed a thrombosed shunt. Ascites has been controlled with a LeVeen shunt in these two patients, but liver biopsies showed progression to cirrhosis. The remaining five patients (three MAS, two MCS) did well, and angiography revealed patent shunts. Two of these patients, however, re-developed ascites at 4 and 10 months following MAS and required a second MAS. Follow-up ranges from 6 to 68 months. In three of the patients (two MCS, one MAS) with patent shunts, liver biopsy shows a remarkable return toward normal liver architecture and histology. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. PMID:6615056

Cameron, J L; Herlong, H F; Sanfey, H; Boitnott, J; Kaufman, S L; Gott, V L; Maddrey, W C

1983-01-01

359

Gauged attenuation of congenital portosystemic shunts: results in 160 dogs and 15 cats.  

PubMed

Portosystemic shunts were ligated over a gauged stainless steel rod in 160 dogs and 15 cats, using a midline celiotomy. The diameter of the rod varied with the size of the shunt and the diameter of the portal vein cranial to the shunt. Shunts were narrowed to the smallest diameter that did not cause signs of portal hypertension such as cyanosis of the stomach, pancreas, and small intestine. A slight discoloration was accepted only if the heart rate, end-expiratory CO2%, or arterial blood pressure (if available) did not deviate more than 15% from the values that were recorded at the beginning of the surgical procedure. The perioperative mortality (0-30 days) was 29%. The most common cause of death was euthanasia because of hypoplasia of the portal vein cranial to the shunt. Animals with intrahepatic shunts had a significantly lower probability of survival than animals with extrahepatic portocaval or portoazygos shunts. In dogs, large breed and a high body weight were also significant risk factors for non-survival. Age had a significant effect on risk of non-survival, with an increased risk for older dogs, irrespective of the breed of the dog (large breed vs. small breed). The probability of survival without recurrence of hepatoencephalopathy (HE) after 1 and 4 years was 61.3% and 55.7%, respectively. The only variable that was significantly associated with non-recurrence of HE was the breed of the dog, there being a lower probability for large breeds. Among the animals that survived surgery for more than 30 days, there was a significant higher probability of recurrence of HE in cats than in dogs. PMID:10789517

Wolschrijn, C F; Mahapokai, W; Rothuizen, J; Meyer, H P; van Sluijs, F J

2000-04-01

360

Structural Basis for the Immunogenic Properties of the Meningococcal Vaccine Candidate LP2086.  

PubMed

LP2086 is a family of outer membrane lipoproteins from Neisseria meningitidis, which elicits bactericidal antibodies and are currently undergoing human clinical trials in a bivalent formulation where each antigen represents one of the two known LP2086 subfamilies. Here we report the NMR structure of the recombinant LP2086 variant B01, a representative of the LP2086 subfamily B. The structure reveals a novel fold composed of two domains: a "taco-shaped" N-terminal beta-sheet and a C-terminal beta-barrel connected by a linker. The structure in micellar solution is consistent with a model of LP2086 anchored to the outer membrane bilayer through its lipidated N terminus. A long flexible chain connects the folded part of the protein to the lipid anchor and acts as spacer, making both domains accessible to the host immune system. Antibodies broadly reactive against members from both subfamilies have been mapped to the N terminus. A surface of subfamily-defining residues was identified on one face of the protein, offering an explanation for the induction of subfamily-specific bactericidal antibodies. PMID:19103601

Mascioni, Alessandro; Bentley, Breagh E; Camarda, Rosaria; Dilts, Deborah A; Fink, Pamela; Gusarova, Viktoria; Hoiseth, Susan K; Jacob, Jaison; Lin, Shuo L; Malakian, Karl; McNeil, Lisa K; Mininni, Terri; Moy, Franklin; Murphy, Ellen; Novikova, Elena; Sigethy, Scott; Wen, Yingxia; Zlotnick, Gary W; Tsao, Désirée H H

2009-03-27

361

Structural Basis for the Immunogenic Properties of the Meningococcal Vaccine Candidate LP2086*S?  

PubMed Central

LP2086 is a family of outer membrane lipoproteins from Neisseria meningitidis, which elicits bactericidal antibodies and are currently undergoing human clinical trials in a bivalent formulation where each antigen represents one of the two known LP2086 subfamilies. Here we report the NMR structure of the recombinant LP2086 variant B01, a representative of the LP2086 subfamily B. The structure reveals a novel fold composed of two domains: a “taco-shaped” N-terminal ?-sheet and a C-terminal ?-barrel connected by a linker. The structure in micellar solution is consistent with a model of LP2086 anchored to the outer membrane bilayer through its lipidated N terminus. A long flexible chain connects the folded part of the protein to the lipid anchor and acts as spacer, making both domains accessible to the host immune system. Antibodies broadly reactive against members from both subfamilies have been mapped to the N terminus. A surface of subfamily-defining residues was identified on one face of the protein, offering an explanation for the induction of subfamily-specific bactericidal antibodies. PMID:19103601

Mascioni, Alessandro; Bentley, Breagh E.; Camarda, Rosaria; Dilts, Deborah A.; Fink, Pamela; Gusarova, Viktoria; Hoiseth, Susan K.; Jacob, Jaison; Lin, Shuo L.; Malakian, Karl; McNeil, Lisa K.; Mininni, Terri; Moy, Franklin; Murphy, Ellen; Novikova, Elena; Sigethy, Scott; Wen, Yingxia; Zlotnick, Gary W.; Tsao, Désirée H. H.

2009-01-01

362

Analysis of error floor of LDPC codes under LP decoding over the BSC  

SciTech Connect

We consider linear programming (LP) decoding of a fixed low-density parity-check (LDPC) code over the binary symmetric channel (BSC). The LP decoder fails when it outputs a pseudo-codeword which is not a codeword. We propose an efficient algorithm termed the instanton search algorithm (ISA) which, given a random input, generates a set of flips called the BSC-instanton and prove that: (a) the LP decoder fails for any set of flips with support vector including an instanton; (b) for any input, the algorithm outputs an instanton in the number of steps upper-bounded by twice the number of flips in the input. We obtain the number of unique instantons of different sizes by running the ISA sufficient number of times. We then use the instanton statistics to predict the performance of the LP decoding over the BSC in the error floor region. We also propose an efficient semi-analytical method to predict the performance of LP decoding over a large range of transition probabilities of the BSC.

Chertkov, Michael [Los Alamos National Laboratory; Chilappagari, Shashi [UNIV OF AZ; Vasic, Bane [UNIV OF AZ; Stepanov, Mikhail [UNIV OF AZ

2009-01-01

363

Destruction of LP XM46 using the molten salt destruction process. Revision 1  

SciTech Connect

The preliminary experimental work done on the destruction of the liquid gun propellant LP XM46 (the new designation for LGP-1846) using the Molten Salt Destruction (MSD) Process at the Lawrence Livermore National Laboratory (LLNL) for the US Army is described in this report. A series of 18 continuous experimental runs were made wherein a solution of LP XM46 and water was injected into a bed of molten salt comprising the carbonates of sodium, potassium and lithium, along with air. The purpose of these initial Phase 1 runs was to collect information on the applicability of the Molten Salt Destruction Process for the destruction of LP XM46, identify the key technical uncertainties, and to plan future runs. The tentative results from these experiments, described in detail in the main body of this report, indicate that: (1) LP XM46 can be safely and completely destroyed in a bed of molten salt at temperatures well below those needed for incineration; and (2) under optimum operating conditions, less than 1% of the chemically bound nitrogen in the LP XM46 is converted to NOx, and less than 1% carbon is converted to CO.

Upadhye, R.S.; Watkins, B.E.

1994-04-01

364

A case of hyperLp(a)aemia, associated with systemic lupus erythematosus, suffering from myocardial infarction and cerebral infarction.  

PubMed

We describe a case of systemic lupus erythematosus (SLE) with nephrotic syndrome who suffered from myocardial infarction and cerebral infarction associated with hyperLp(a)aemia. The proband was an 18-year-old Japanese male who was found to have hypercholesterolemia and hyperLp(a)aemia, with a serum total cholesterol level of 361 mg/dl and a serum Lp(a) level of 197 mg/dl. His father and mother showed higher Lp(a)levels (26 and 56 mg/dl, respectively) than those in normals (18 +/- 0.6 mg/dl, mean +/- SE). Lp(a)glycoprotein phenotypes were examined. The proband had the phenotype S2/4, which is associated with high Lp(a) concentration. His parents had the phenotype S3/4 and S2/4. No cardiovascular diseases were noted in other members of his family. After treatment with CS-514, a competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase. Lp(a) levels decreased from 197 to 121 mg/dl, but still remained abnormally high. LDL apheresis using a Liposorber system was attempted in this patient. Total and LDL cholesterol levels decreased by 57 and 62%, respectively. Lp(a) levels decreased by 68%. These results suggest that LDL apheresis may be an alternative therapy in drug resistant hyperLp(a)aemia. PMID:2145457

Takegoshi, T; Haba, T; Hirai, J; Saga, T; Kitoh, C; Mabuchi, H

1990-01-01

365

Investigating the source characteristics of long-period (LP) seismic events recorded on Piton de la Fournaise volcano, La Réunion  

NASA Astrophysics Data System (ADS)

Magmatic and hydrothermal processes play a significant role in generating seismicity at active volcanoes. These signals can be recorded at the surface and can be used to obtain an insight into the volcano's internal dynamics. Long period (LP) events are of particular interest as they often accompany or precede volcanic eruptions, but they are still not well understood. Piton de la Fournaise volcano, La Réunion Island, is one of the most active volcanoes in the world however LP events are rarely recorded there. A seismic network of 20 broadband seismometers has been operational on Piton de la Fournaise volcano since November 2009. Between November 2009 and January 2011 the volcano erupted five times, but only 15 LP events were recorded. Three of these eruptions were preceded by LP events, and several LP events were recorded during an intrusive phase. A family of three repeating LP events exists within the dataset. In order to characterize these events we locate and perform moment tensor inversion on the LP family. The LP events are located within the summit crater at shallow depths (< 200 m below the surface). Inversions show that the source mechanism is best represented by a tensile crack with horizontal crack geometry. We also investigate the relationship between LP occurrence and eruptive characteristics (size of the eruption, deformation of the edifice, etc.), and we find that the events exist only during flank eruptions and can be generated by the activity of the hydrothermal system and/or by the deformation inside the crater.

Zecevic, Megan; De Barros, Louis; Bean, Christopher J.; O'Brien, Gareth S.; Brenguier, Florent

2013-05-01

366

External lumbar drain: A pragmatic test for prediction of shunt outcomes in idiopathic normal pressure hydrocephalus  

PubMed Central

Background: The consensus on most reliable supplemental test to predict the shunt responsiveness in patients with idiopathic normal pressure hydrocephalus (iNPH) is lacking. The aim of this study is to discuss the utility of external lumbar drain (ELD) in evaluation of shunt responsiveness for iNPH patients. Methods: A retrospective review of 66 patients with iNPH was conducted. All patients underwent 4-day ELD trial. ELD-positive patients were offered ventriculoperitoneal shunt (VPS) surgery. The primary outcome evaluation parameters were gait and mini mental status examination (MMSE) assessment. The family and patient perception of improvement was accounted for in the outcome evaluation. Results: There were 38 male and 28 female with mean age of 74 years (range 45-88 years). ELD trial was positive in 86% (57/66) of patients. No major complications were encountered with the ELD trial. A total of 60 patients (57 ELD-positive, 3 ELD-negative) underwent VPS insertion. The negative ELD trial (P = 0.006) was associated with poor outcomes following shunt insertion. The positive ELD trial predicted shunt responsiveness in 96% patients (P < 0.0001, OR = 96.2, CI = 11.6-795.3). A receiver operating characteristic (ROC) curve analysis revealed that the ELD trial is reasonably accurate in differentiating shunt responder from non-responder in iNPH patients (area under curve = 0.8 ± 0.14, P = 0.02, CI = 0.52-1.0). The mean follow-up period was 12-months (range 0.3-3 years). The significant overall improvement after VPS was seen in 92% (55/60). The improvement was sustained in 76% of patients at mean 3-year follow-up. The number of comorbid conditions (P = 0.034, OR = 4.15, CI = 1.2-9.04), and a history of cerebrovascular accident (CVA) (P = 0.035, OR = 4.4, CI = 1.9-14.6) were the predictors of poor outcome following shunt surgery. Conclusion: The positive ELD test predicted shunt responsiveness in 96% of patients. With adequate technique, maximal results with minimal complications can be anticipated. The number of comorbidities, history of CVA and negative ELD test were significantly associated with poor shunt outcomes. PMID:24678428

Chotai, Silky; Medel, Ricky; Herial, Nabeel A.; Medhkour, Azedine

2014-01-01

367

Pre- and post-shunting observations in adult sheep with kaolin-induced hydrocephalus  

PubMed Central

Background The objective of this study was to examine host-shunt interactions in sheep with kaolin-induced hydrocephalus. Methods Forty-two sheep (29–40 kg) were utilized for this study. In 20 animals, various kaolin doses were injected into the cisterna magna including 10 and 50 mg/kg as well as 2–4 ml of a 25% kaolin suspension. Based on animal health and hydrocephalus development, 3 ml of a 25% kaolin suspension was chosen. In 16 animals, kaolin was administered and 6–8 days later, the animals received a custom made ventriculo-peritoneal shunt. In 8 animals ventricular CSF pressures were measured with a water manometer before kaolin administration and 7–8 days later. The sheep were allowed to survive for up to 9–12 weeks post-kaolin or until clinical status required euthanasia. Brains were assessed for morphological and histological changes. Ventricle/cerebrum cross sectional area ratios (V/C) were calculated from photographs of the sliced coronal planes immediately anterior to the interventricular foramina. Results Intraventricular pressures increased from 12.4±1.1 cm H2O to 41.3±3.5 cm H2O following kaolin injection (p?0.10) ventricular expansion. The animals lost weight between kaolin administration and shunting (33.7±1.2 kg versus 31.0±1.7 kg) with weights after shunting remaining stable up to sacrifice (31.6±2.2 kg). Of 16 shunted animals, 5 did well and were sacrificed 9–12 weeks post-kaolin. In the remainder, the study was terminated at various times due to deteriorating health. Hydrocephalus was associated with thinning of the corpus callosum, but no obvious loss of myelin staining, along with reactive astroglial (glial fibrillary acidic immunoreactive) and microglial (Iba1 immunoreactive) changes in the white matter. Ventricular shunts revealed choroid plexus ingrowth in 5/16, brain tissue ingrowth in 1/16, problems with shunt insertion in 3/16, occlusion by hemorrhagic-inflammatory material in 5/16, or no obstruction in 2/16. Free flowing CSF indicated that the peritoneal catheter was patent. Conclusions Cerebrospinal fluid shunts in hydrocephalic sheep fail in ways that are reminiscent of human neurosurgical experience suggesting that this model may be helpful in the development of more effective shunt technology. PMID:23845003

2013-01-01

368

Simulations reveal adverse hemodynamics in patients with multiple systemic to pulmonary shunts.  

PubMed

For newborns diagnosed with pulmonary atresia or severe pulmonary stenosis leading to insufficient pulmonary blood flow, cyanosis can be mitigated with placement of a modified Blalock-Taussig shunt (MBTS) between the innominate and pulmonary arteries. In some clinical scenarios, patients receive two systemic-to-pulmonary connections, either by leaving the patent ductus arteriosus (PDA) open or by adding an additional central shunt (CS) in conjunction with the MBTS. This practice has been motivated by the thinking that an additional source of pulmonary blood flow could beneficially increase pulmonary flow and provide the security of an alternate pathway in case of thrombosis. However, there have been clinical reports of premature shunt occlusion when more than one shunt is employed, leading to speculation that multiple shunts may in fact lead to unfavorable hemodynamics and increased mortality. In this study, we hypothesize that multiple shunts may lead to undesirable flow competition, resulting in increased residence time (RT) and elevated risk of thrombosis, as well as pulmonary overcirculation. Computational fluid dynamics-based multiscale simulations were performed to compare a range of shunt configurations and systematically quantify flow competition, pulmonary circulation, and other clinically relevant parameters. In total, 23 cases were evaluated by systematically changing the PDA/CS diameter, pulmonary vascular resistance (PVR), and MBTS position and compared by quantifying oxygen delivery (OD) to the systemic and coronary beds, wall shear stress (WSS), oscillatory shear index (OSI), WSS gradient (WSSG), and RT in the pulmonary artery (PA), and MBTS. Results showed that smaller PDA/CS diameters can lead to flow conditions consistent with increased thrombus formation due to flow competition in the PA, and larger PDA/CS diameters can lead to insufficient OD due to pulmonary hyperfusion. In the worst case scenario, it was found that multiple shunts can lead to a 160% increase in RT and a 10% decrease in OD. Based on the simulation results presented in this study, clinical outcomes for patients receiving multiple shunts should be critically investigated, as this practice appears to provide no benefit in terms of OD and may actually increase thrombotic risk. PMID:25531794

Esmaily-Moghadam, Mahdi; Murtuza, Bari; Hsia, Tain-Yen; Marsden, Alison

2015-03-01

369

Decompensated porto-pulmonary hypertension in a cirrhotic patient with thrombosis of portocaval shunt  

PubMed Central

We report a case of decompensated porto-pulmonary hypertension closely associated with the development of intra-portocaval shunt thrombosis. A woman with Laennec's cirrhosis was hospitalized because of severe dyspnea and edema. She underwent surgical portocaval anastomosis ten years ago. Imaging studies showed massive intra-shunt thrombosis, portal hypertension, ascites, pleuro-pericardial effusions and enlargement of right cardiac cavities. Cardiac catheterization allowed to rule out coronary and left-sided heart abnormalities and led to the diagnosis of pre-capillary pulmonary hypertension. Antithrombotic treatment with low molecular weight heparin was instituted. The management also included ACE inhibitors, spironolactone, low-salt diet and lactulose. The patient was discharged and three months later we observed the disappearance of edema, ascites and pleuro-pericardial effusions, a marked body weight reduction and improved dyspnea and liver function tests. A possible link between the development of intra-shunt thrombosis and clinical decompensation in our patient was hypothesized. In fact, it has been demonstrated that the increased portal pressure, caused by occlusion of portosystemic shunt, reduces renal plasma flow and increases systemic endothelin-1 concentration. In our patient the disappearance of edematous state and improved dyspnea observed after recanalization of the shunt strongly support this hypothesis. PMID:18081237

Giannarelli, Chiara; De Giorgi, Antonio; De Negri, Ferdinando; Carmassi, Franco

2007-01-01

370

Intraoperative measurement of Javid shunt flow with transit-time ultrasound.  

PubMed

Transit-time ultrasound methods were used to measure blood flow in 37 patients undergoing carotid endarterectomy. Internal carotid flow before (ICFbef) and after (ICFaft) endarterectomy was measured with a 6 mm perivascular probe, and Javid shunt flow (SF) was measured with a clamp-on probe. For the entire group ICFbef averaged 117 +/- 67 ml/min and ICFaft was 173 +/- 67 ml/min. Shunt flow averaged 123 +/- 51 ml/min. The differences between ICFbef and ICFaft and between SF and ICFaft were significant (ANOVA, p < 0.01) but the difference between ICFbef and SF was not. The relationship between ICFbef and SF appeared to define two groups of patients. Those in whom SF was greater than ICFbef (SF > ICFbef) had more stenosis evident on preoperative arteriograms (64.7% +/- 14.55% maximum single diameter stenosis) and a greater average increase in ICF (151% +/- 159%) than those with SF < or = ICFbef (43.3% +/- 20.9% stenosis and 34% +/- 54% increase in ICF), suggesting that the relationship between SF and ICFbef defines groups with different hemodynamic responses. The similarity between SF and ICFbef indicates that Javid shunt flow offers adequate protection from cerebral ischemia. A practical benefit of the shunt clamp-on flow probe is the ability afforded to recognize shunt occlusions. PMID:7865396

Gordon, I L; Weil, D J; Williams, R A; Wilson, S E

1994-11-01

371

Our experiences with saphenoperitoneal shunts in the treatment of intractable ascites.  

PubMed

Because of significant expenses and complication rates of traditional pumps (LeVeen, Denver, Agishi) used in the surgical treatment of refractory ascites a simple and cheap operative method has to be found. In saphenoperitoneal shunts the one-way flow is maintained by biologically given double saphenous valves. In our department 11 saphenoperitoneal shunts have been performed on 9 patients (2 female, 7 male) in the past one and a half years. Their ascites have been associated with cirrhosis of the liver (secondary to aethylism in 8, to HBV infection in 1). During the follow-up period significant reduction in body weight and abdominal girth, and increase in diuresis with standard diuretics were seen in 6 patients. The minor complications (3 seromas, 3 hematomas, 2 cellulitis) have been self-limiting in general. In the presence of major complications (1 peritoneal reflux, 1 severe hypoproteinaemia, 3 shunt occlusion) interventions were needed several times. In one of the occlusions contralateral fistula was created with PTFE prosthesis implantation, in another case desobliteration happened with a silicone drain left in the shunt. The saphenoperitoneal shunts could improve quality of life significantly in successful instances with minimal negative operative effects without the adverse effects of insertion of foreign material. PMID:15966232

Vizsy, Laszlo; Beznicza, Henrietta; Batorfi, Jozsef

2005-01-01

372

Clinical and radiologic manifestations of congenital extrahepatic portosystemic shunts: a comprehensive review.  

PubMed

Congenital extrahepatic portosystemic shunt (CEPS) is a rare condition in which the portomesenteric blood drains into a systemic vein, bypassing the liver through a complete or partial shunt. Most often, the diagnosis is made primarily with Doppler ultrasonography. Computed tomographic angiography and magnetic resonance angiography are used for further classification of the shunt and assessment of accompanying anomalies. Conventional angiography is necessary when results of the other tests disagree or are inconclusive. CEPS is classified into two types according to the pattern of anastomoses between the portal vein and systemic vein. In type 1, intrahepatic portal venous supply is absent; in type 2, intrahepatic portal venous supply is preserved. Type 1 usually occurs in girls with associated malformations, such as situs ambiguous with polysplenia and congenital heart defects. Associated anomalies are less frequent in type 2, and symptoms usually develop later without a gender preference. Hepatic encephalopathy and liver dysfunction are possible complications of both types and usually develop during adulthood. Both types are also associated with regenerative hepatic nodules. The clinical setting and imaging appearance of these nodules can help one avoid misdiagnosis. Definitive treatment of CEPS is determined by the type of shunt. Liver transplantation is the only effective treatment for symptomatic type 1 CEPS; surgical closure or embolization of the shunt is the therapeutic approach for type 2. PMID:21571652

Alonso-Gamarra, Eduardo; Parrón, Manuel; Pérez, Ana; Prieto, Consuelo; Hierro, Loreto; López-Santamaría, Manuel

2011-01-01

373

Contrast-enhanced magnetic resonance angiography for diagnosis of portosystemic shunts in 10 dogs.  

PubMed

Computed tomography angiography, sonography, scintigraphy, and portography can be used to evaluate the portal vasculature to evaluate for a portosystemic shunt (PSS). Time-of-flight magnetic resonance angiography (TOF-MRA) and contrast-enhanced MRA (CE-MRA) are other potentially useful techniques. The aim of this study was to evaluate CE-MRA in 10 dogs suspected of having a PSS. Noncontrast MR images of the abdomen were obtained using a Siemens Symphony MR-scanner (1.5 T) and a T1-weighted FLASH-3D sequence with a very short scan time (about 20 s). After injection of contrast medium, the initial sequence was repeated five times. The sequence with the best contrast medium filling of the portal vasculature was selected subjectively, subtracted from the initial survey image series, and a maximum intensity projection (MIP) of the subtraction data, in multiple views, was created. The cross-sectional and MIP images were evaluated for abnormal portosystemic vasculature. A single PSS was identified and confirmed at surgery in all dogs. A portocaval shunt was found in five dogs, a portophrenic shunt in three dogs, a portoazygos shunt in one, and a central divisional intrahepatic shunt in one other dog. Based on our results, CE-MRA is a useful tool for imaging abdominal and portal vasculature and for the diagnosis of a PSS. PMID:20402393

Bruehschwein, Andreas; Foltin, Isa; Flatz, Katharina; Zoellner, Martin; Matis, Ulrike

2010-01-01

374

Complications and long-term outcomes of the ligation of congenital portosystemic shunts in 49 cats.  

PubMed

Only two of 49 cats undergoing surgical ligation of congenital extra- and intrahepatic portosystemic shunts died perioperatively, a mortality rate comparable with the mortality rates of dogs undergoing surgical attenuation of congenital portosystemic shunts and cats in which the shunts are attenuated with an ameroid ring constrictor. Thirty (83 per cent) of the 36 cats for which long-term information was available were still alive at a median follow-up period of 47 months (range six to 105 months); the outcome was excellent (no clinical signs) in 20 of them (median follow-up 37 months, range six to 105 months) and good (minimal clinical signs) in seven (median follow-up 39 months, range 10 to 73 months) and none of these 27 cats was on any long-term medication or special diet. The only major cause of morbidity was the development of neurological signs in 18 (37 per cent) of the cats. These included seizures and a wide variety of other neurological signs, and their development and persistence was not affected by the presence of preoperative seizures, the type of shunt, the degree of shunt attenuation or the age of the cat. The serum concentrations of ammonia and preprandial bile acids were normal or significantly below normal in the cats with neurological signs. Liver histopathology was similar in the cats with and without neurological signs. Ten (56 per cent) of the 18 cats that developed neurological signs recovered normal neurological function long term. PMID:17416722

Lipscomb, V J; Jones, H J; Brockman, D J

2007-04-01

375

The C57BL/6J Mouse Exhibits Sporadic Congenital Portosystemic Shunts  

PubMed Central

C57BL/6 mice are the most widely used strain of laboratory mice. Using in vivo proton Magnetic Resonance Spectroscopy (1H MRS), we have repeatedly observed an abnormal neurochemical profile in the brains of both wild-type and genetically modified mice derived from the C57BL/6J strain, consisting of a several fold increase in cerebral glutamine and two fold decrease in myo-inositol. This strikingly abnormal neurochemical “phenotype” resembles that observed in chronic liver disease or portosystemic shunting and appeared to be independent of transgene, origin or chow and was not associated with liver failure. As many as 25% of animals displayed the abnormal neurochemical profile, questioning the reliability of this model for neurobiology. We conducted an independent study to determine if this neurochemical profile was associated with portosystemic shunting. Our results showed that 100% of the mice with high brain glutamine displayed portosystemic shunting by concomitant portal angiography while all mice with normal brain glutamine did not. Since portosystemic shunting is known to cause alterations in gene expression in many organs including the brain, we conclude that portosystemic shunting may be the most significant problem associated with C57BL/6J inbreeding both for its effect on the central nervous system and for its systemic repercussions. PMID:23936100

Lei, Hongxia; Duarte, Joao M. N.; Rougemont, Anne-Laure; Oldani, Graziano; Terraz, Sylvain; Toso, Christian; Gruetter, Rolf

2013-01-01

376

Intraoperative ultrasonography of the portal vein during attenuation of intrahepatic portocaval shunts in dogs.  

PubMed

A method for intraoperative measurement of portal blood flow velocity with duplex Doppler ultrasonography in 7 dogs with congenital intrahepatic portosystemic shunts is described. The aims of the study were to determine whether intraoperative ultrasonography was an acceptable alternative to mesenteric portography in such dogs and to identify quantitative portal hemodynamic variables that might correlate with clinical outcome better than portal pressure does. Ultrasonographic measurements did not influence decision-making by the surgeon, who attenuated the shunt on the basis of appearance of the viscera and change in mean systemic arterial blood pressure. All dogs recovered without complications, and surgery was considered to be successful in all 7. Intraoperative B-mode ultrasonography provided real-time information about the anatomy of the shunt and the portal branches, suggesting that it may be a useful alternative to mesenteric portography. The time-averaged mean portal blood velocity ranged from 6.5 to 33.7 cm/s before shunt attenuation and from 5.0 to 9.5 cm/s after shunt attenuation. This narrow range of postligation velocities suggested that intraoperative ultrasonography might be an alternative to intraoperative portal pressure measurement. PMID:12710771

Szatmári, Viktor; van Sluijs, Frederik J; Rothuizen, Jan; Voorhout, George

2003-04-15

377

Rex shunt for portal vein thrombosis after adult living donor liver transplantation.  

PubMed

Portal vein thrombosis (PVT) after liver transplantation is a relatively common but serious complication which could lead to portal hypertension or a direct graft loss. A "Rex" shunt created between the superior mesenteric vein (SMV) and the umbilical portion of the left portal vein can be a useful option to treat PVT after pediatric liver transplantation, however, its application to adult patients has not been reported so far because appropriate vein grafts are hardly available. Herein we present a case of PVT after left lobe living donor liver transplantation (LDLT) who underwent the procedure using the own inferior jugular vein and the gonadal vein as a shunt graft. The shunt was patent immediately after the procedure but was thrombosed 2 days after probably due to the insufficient inflow from the SMV and the absence of anticoagulation therapy, for which emergent thrombectomy and ligation of the significant hepatofugal collateral veins followed by full anti-coagulation therapy were performed. The shunt remains open at 8 month after the procedure with a normal anmonia level and liver function. In conclusion, the Rex shunt using recipient's autologous vein grafts is a feasible and valuable option for adult patients to treat PVT after LDLT. PMID:24620643

Soejima, Yuji; Shirabe, Ken; Yoshizumi, Tomoharu; Uchiyama, Hideaki; Ikegami, Toru; Yamashita, Yo-Ichi; Ikeda, Tetsuo; Kawanaka, Hirofumi; Sugimachi, Keishi; Mimori, Koshi; Watanabe, Masayuki; Morita, Masaru; Oki, Eiji; Saeki, Hiroshi; Maehara, Yoshihiko

2013-11-01

378

Risk factors for tube shunt exposure: a matched case-control study.  

PubMed

Purpose. To evaluate potential risk factors for developing tube shunt exposure in glaucoma patients. Patients and Methods. Forty-one cases from 41 patients that had tube shunt exposure from 1996 to 2005 were identified from the Robert Cizik Eye Clinic and Bascom Palmer Eye Institute. Each case was matched with 2 controls of the same gender and with tube shunts implanted within 6 months of the index case. Conditional logistic regression was used to determine risk factors. Results. The study cohort includes a total of 121 eyes from 121 patients. The mean age was 63.6?±?19.7 years, ranging from 1 to 96 years. The average time to exposure was 19.29?±?23.75 months (range 0.36-85.74 months). Risk factors associated with tube exposure were Hispanic ethnicity (P = 0.0115; OR?=?3.6; 95% CI, 1.3-9.7), neovascular glaucoma (P = 0.0064; OR?=?28.5; 95% CI, 2.6-316.9), previous trabeculectomy (P = 0.0070; OR?=?5.3; 95% CI, 1.6-17.7), and combined surgery (P = 0.0381; OR?=?3.7; 95% CI, 1.1-12.7). Conclusions. Hispanic ethnicity, neovascular glaucoma, previous trabeculectomy, and combined surgery were identified as potential risk factors for tube shunt exposure. These potential risk factors should be considered when determining the indication for performing tube shunt implantation and the frequency of long-term followup. PMID:23970955

Koval, Michael S; El Sayyad, Fouad F; Bell, Nicholas P; Chuang, Alice Z; Lee, David A; Hypes, Stephen M; Grover, Davinder S; Baker, Laura A; Huddleston, Stephen M; Budenz, Donald L; Feldman, Robert M

2013-01-01

379

Accelerated pubertal development in patients with shunted hydrocephalus.  

PubMed Central

OBJECTIVE: To evaluate pubertal development and peripheral concentrations of gonadotrophins and sex hormones in children with shunted hydrocephalus compared with healthy controls. STUDY DESIGN: 114 patients (52 females, 62 males) and 73 healthy controls (35 females, 38 males) aged 5 to 20 years were analysed for stage of puberty, age at menarche, testicular volume, basal serum follicle stimulating hormone (FSH), luteinising hormone (LH), sex hormone binding globulin (SHBG), testosterone and oestradiol concentrations, and free androgen index. RESULTS: Male gonadal and male and female pubic hair development occurred significantly earlier in the patients than in the controls. The mean age at menarche was significantly lower in the female patients than in their controls (11.7 v 13.2 years; p < 0.001), and lower than it had been for their mothers (v 13.1 years; p < 0.001). Relative testicular volume was higher in the male patients than in their controls (1.2 standard deviation score (SDS) v 0.2 SDS; p < 0.001). The prepubertal patients had higher basal LH (0.13 U/l v 0.08 U/l; p < 0.001) and SHBG (132.3 nmol/l v 109.1 nmol/l; p < 0.01) than the controls. Both the prepubertal and pubertal females had significantly higher basal FSH than their controls (1.57 U/l v 1.03 U/l; p < 0.05, and 4.0 U/l v 2.9 U/l; p < 0.01, respectively). CONCLUSIONS: Hydrocephalic children experience accelerated pubertal maturation, reflected in a younger age at menarche in females and an increased testicular volume in males. This may be because of enhanced gonadotrophin secretion, possibly resulting from unphysiological variations in intracranial pressure. PMID:8758123

Löppönen, T; Saukkonen, A L; Serlo, W; Tapanainen, P; Ruokonen, A; Knip, M

1996-01-01

380

Ultrasonographic diagnosis of portosystemic shunting in dogs and cats.  

PubMed

The value of ultrasonography was evaluated in 85 dogs and 17 cats presented with a clinically suspected portosystemic shunt (PSS). A PSS was confirmed in 50 dogs and nine cats (single congenital extrahepatic in 42, single congenital intrahepatic in 11, and multiple acquired in six). Six dogs and one cat had hepatic microvascular dysplasia, and 29 dogs and seven cats had a normal portal system. Ultrasonography was 92% sensitive, 98% specific, and had positive and negative predictive values of 98% and 89%, respectively, in identifying PSS, with an overall accuracy of 95%. When a PSS was identified with ultrasonography, extrahepatic, intrahepatic, and multiple acquired PSS could be correctly differentiated in 53/54 patients (98%). The combination of a small liver, large kidneys, and uroliths had positive and negative predictive values of 100% and 51% for the presence of a congenital PSS in dogs. The portal vein/aorta (PV/Ao) and portal vein/caudal vena cava (PV/ CVC) ratios were smaller in animals with extrahepatic PSSs compared with animals with microvascular dysplasia, intrahepatic PSSs and those without portal venous anomalies (P<0.001). All dogs and cats with a PV/Ao ratio of < or = 0.65 had an extrahepatic PSS or idiopathic noncirrhotic portal hypertension. Dogs and cats with PV/Ao and PV/CVC ratios of > or = 0.8 and > or = 0.75, respectively, did not have an extrahepatic PSS. Reduced or reversed portal flow was seen in four of four patients with multiple acquired PSSs secondary to portal hypertension. The presence of turbulence in the caudal vena cava of dogs had positive and negative predictive values of 91% and 84%, respectively, for the presence of any PSS terminating into that vein. PMID:15487568

d'Anjou, Marc-André; Penninck, Dominique; Cornejo, Lilian; Pibarot, Philippe

2004-01-01

381

Transjugular intrahepatic portosystemic shunts and portal hypertension-related complications  

PubMed Central

Portal hypertension (PH) plays an important role in the natural history of cirrhosis, and is associated with several clinical consequences. The introduction of transjugular intrahepatic portosystemic shunts (TIPS) in the 1980s has been regarded as a major technical advance in the management of the PH-related complications. At present, polytetrafluoroethylene-covered stents are the preferred option over traditional bare metal stents. TIPS is currently indicated as a salvage therapy in patients with bleeding esophageal varices who fail standard treatment. Recently, applying TIPS early (within 72 h after admission) has been shown to be an effective and life-saving treatment in those with high-risk variceal bleeding. In addition, TIPS is recommended as the second-line treatment for secondary prophylaxis. For bleeding gastric varices, applying TIPS was able to achieve hemostasis in more than 90% of patients. More trials are needed to clarify the efficacy of TIPS compared with other treatment modalities, including cyanoacrylate injection and balloon retrograde transvenous obliteration of gastric varices. TIPS should also be considered in bleeding ectopic varices and refractory portal hypertensive gastropathy. In patients with refractory ascites, there is growing evidence that TIPS not only results in better control of ascites, but also improves long-term survival in appropriately selected candidates. In addition, TIPS is a promising treatment for refractory hepatic hydrothorax. However, the role of TIPS in the treatment of hepatorenal and hepatopulmonary syndrome is not well defined. The advantage of TIPS is offset by a risk of developing hepatic encephalopathy, the most relevant post-procedural complication. Emerging data are addressing the determination the optimal time and patient selection for TIPS placement aiming at improving long-term treatment outcome. This review is aimed at summarizing the published data regarding the application of TIPS in the management of complications related to PH. PMID:25493012

Siramolpiwat, Sith

2014-01-01

382

z=0 z=0 z=0 Steam-turbin Condenser LP-pump  

E-print Network

¡ ¢£ ¤ ¥§¦ ¨ © ¥£ ¡ £ ¨ © ¦ ¦ ¡ £ ¨ © ¦ ¦ ¥ ¦ © © ¡ ¥ ¥ £ ¦ ¡ ! ¦ " ©# £ $ ¤ #12; 4 ¡ 3 @ ¢ 2 6 3 F 4 9 7 LC LC PC z=0 z=0 z=0 z=1 z=1 TC TC z=0 HP-pump Steam-turbin Condenser LP-pump Air compressor Deaerator HP-pump Steam-turbin Condenser LP-pump Air compressor Deaerator HP-pump Condenser LP-pump Air compressor Deaerator Pre-heaterSuper-heater Evaporator Economizer Condenser drum Gas

Skogestad, Sigurd

383

Effects of topography and crustal heterogeneities on the source estimation of LP event at Kilauea volcano  

USGS Publications Warehouse

The main goal of this study is to improve the modelling of the source mechanism associated with the generation of long period (LP) signals in volcanic areas. Our intent is to evaluate the effects that detailed structural features of the volcanic models play in the generation of LP signal and the consequent retrieval of LP source characteristics. In particular, effects associated with the presence of topography and crustal heterogeneities are here studied in detail. We focus our study on a LP event observed at Kilauea volcano, Hawaii, in 2001 May. A detailed analysis of this event and its source modelling is accompanied by a set of synthetic tests, which aim to evaluate the effects of topography and the presence of low velocity shallow layers in the source region. The forward problem of Green's function generation is solved numerically following a pseudo-spectral approach, assuming different 3-D models. The inversion is done in the frequency domain and the resulting source mechanism is represented by the sum of two time-dependent terms: a full moment tensor and a single force. Synthetic tests show how characteristic velocity structures, associated with shallow sources, may be partially responsible for the generation of the observed long-lasting ringing waveforms. When applying the inversion technique to Kilauea LP data set, inversions carried out for different crustal models led to very similar source geometries, indicating a subhorizontal cracks. On the other hand, the source time function and its duration are significantly different for different models. These results support the indication of a strong influence of crustal layering on the generation of the LP signal, while the assumption of homogeneous velocity model may bring to misleading results. ?? 2008 The Authors Journal compilation ?? 2008 RAS.

Cesca, S.; Battaglia, J.; Dahm, T.; Tessmer, E.; Heimann, S.; Okubo, P.

2008-01-01

384

Interaction between VLDL and phosphatidylcholine liposomes generates new ?-LpE-like particles.  

PubMed

One of the subfractions of HDL involved in reverse cholesterol transport is ?-LpE. It has been assumed that, like pre?-LpAI, it can be generated during the interaction between phosphatidylcholine liposomes and lipoproteins and can contribute to more efficient cholesterol efflux after the introduction of liposomes to plasma. However, there has been no evidence concerning what the sources of these particles in plasma might be. Here, we determined whether the interaction of phosphatidylcholine liposomes with VLDL and the subsequent conversions of particles could be a source of new ?-LpE particles. We found that the interaction between liposomes and VLDL affected its lipid and protein composition. The content of phospholipids increased (~96 %) while the content of free cholesterol and apolipoprotein E decreased in VLDL during the reaction with liposomes (~100 and ~24 %, respectively). New particles which did not contain apolipoprotein B were generated. Heterogeneous HDL-sized populations of particles were generated, containing phospholipids and apolipoprotein E as the sole apolipoprotein, with densities from 1.063 to 1.21 g/ml, either with ?-mobility on agarose gel and Stokes diameters from 8.58 to 22.07 nm or with pre?-mobility and Stokes diameters from 9.9 to 21.08 nm. The obtained results contribute to the understanding of changes in lipoproteins under the influence of phosphatidylcholine liposomes, showing the formation of new (?-LpE)-like and (pre?-LpE)-like particles, similar in mobility and size to plasma HDL-LpE. These newly generated particles can claim a share of the antiatherogenic effects of liposomes, observed in studies both in vitro and in vivo. PMID:24234844

?wikli?ska, Agnieszka; Kortas-Stempak, Barbara; Gliwi?ska, Anna; Pacanis, Anastasis; Kuchta, Agnieszka; Wróblewska, Ma?gorzata

2014-02-01

385

Percutaneous vesicoamniotic shunting versus conservative management for fetal lower urinary tract obstruction (PLUTO): a randomised trial  

PubMed Central

Summary Background Fetal lower urinary tract obstruction (LUTO) is associated with high perinatal and long-term childhood mortality and morbidity. We aimed to assess the effectiveness of vesicoamniotic shunting for treatment of LUTO. Methods In a randomised trial in the UK, Ireland, and the Netherlands, women whose pregnancies with a male fetus were complicated by isolated LUTO were randomly assigned by a central telephone and web-based randomisation service to receive either the intervention (placement of vesicoamniotic shunt) or conservative management. Allocation could not be masked from clinicians or participants because of the invasive nature of the intervention. Diagnosis was by prenatal ultrasound. The primary outcome was survival of the baby to 28 days postnatally. All primary analyses were done on an intention-to-treat basis, but these results were compared with those of an as-treated analysis to investigate the effect of a fairly large proportion of crossovers. We used Bayesian methods to estimate the posterior probability distribution of the effectiveness of vesicoamniotic shunting at 28 days. The study is registered with the ISRCTN Register, number ISRCTN53328556. Findings 31 women with singleton pregnancies complicated by LUTO were included in the trial and main analysis, with 16 allocated to the vesicoamniotic shunt group and 15 to the conservative management group. The study closed early because of poor recruitment. There were 12 livebirths in each group. In the vesicoamniotic shunt group one intrauterine death occurred and three pregnancies were terminated. In the conservative management group one intrauterine death occurred and two pregnancies were terminated. Of the 16 pregnancies randomly assigned to vesicoamniotic shunting, eight neonates survived to 28 days, compared with four from the 15 pregnancies assigned to conservative management (intention-to-treat relative risk [RR] 1·88, 95% CI 0·71–4·96; p=0·27). Analysis based on treatment received showed a larger effect (3·20, 1·06–9·62; p=0·03). All 12 deaths were caused by pulmonary hypoplasia in the early neonatal period. Sensitivity analysis in which non-treatment-related terminations of pregnancy were excluded made some slight changes to point estimates only. Bayesian analysis in which the trial data were combined with elicited priors from experts suggested an 86% probability that vesicoamniotic shunting increased survival at 28 days and a 25% probability that it had a large, clinically important effect (defined as a relative increase of 55% or more in the proportion of neonates who survived). There was substantial short-term and long-term morbidity in both groups, including poor renal function—only two babies (both in the shunt group) survived to 2 years with normal renal function. Seven complications occurred in six fetuses from the shunt group, including spontaneous ruptured membranes, shunt blockage, and dislodgement. These complications resulted in four pregnancy losses. Interpretation Survival seemed to be higher in the fetuses receiving vesicoamniotic shunting, but the size and direction of the effect remained uncertain, such that benefit could not be conclusively proven. Our results suggest that the chance of newborn babies surviving with normal renal function is very low irrespective of whether or not vesicoamniotic shunting is done. Funding UK National Institute of Health Research, Wellbeing of Women, Hannah Eliza Guy Charity (Birmingham Children's Hospital Charity). PMID:23953766

Morris, Rachel K; Malin, Gemma L; Quinlan-Jones, Elisabeth; Middleton, Lee J; Hemming, Karla; Burke, Danielle; Daniels, Jane P; Khan, Khalid S; Deeks, Jon; Kilby, Mark D

2013-01-01

386

Computed tomography findings of spontaneous porto-pulmonary shunts in 3 patients with portal hypertension.  

PubMed

Spontaneous portopulmonary shunts in the setting of cirrhosis have been associated with the embolization of gelfoam during the treatment of esophageal varices, resulting in strokes. Currently there is minimal data describing the prevalence of spontaneous portopulmonary shunts. Our aim is to demonstrate computed tomography (CT) imaging findings of spontaneous portopulmonary venous anastomoses in patients with underlying portal hypertension. Clinical cases with accompanying CT images are presented and described. A review of the literature is discussed. CT is a useful method for identifying shunting, both spontaneous and surgical, of the portal circulation secondary to hypertension. A less known type of anastomosis involves the pulmonary circulation, specifically the pulmonary veins and left atrium, that can also be recognized with CT. PMID:20351579

Kumar, Anand; Gonzalez, German; Wilkinson, Lana; Mohammed, Tan-Lucien; Castro-Pavia, Fernando; Glockner, James; Kirsch, Jacobo

2010-08-01

387

Resistance to Diet-Induced Obesity in Mice with Synthetic Glyoxylate Shunt  

PubMed Central

Summary Given the success in engineering synthetic phenotypes in microbes and mammalian cells, constructing non-native pathways in mammals has become increasingly attractive for understanding and identifying potential targets for treating metabolic disorders. Here we introduced the glyoxylate shunt into mouse liver to investigate mammalian fatty acid metabolism. Mice expressing the shunt showed resistance to diet-induced obesity on a high fat diet despite similar food consumption. This was accompanied by a decrease in total fat mass, circulating leptin levels, plasma triglyceride concentration, and a signaling metabolite in liver, malonyl-CoA, that inhibits fatty acid degradation. Contrary to plants and bacteria, in which the glyoxylate shunt prevents the complete oxidation of fatty acids, this pathway when introduced in mice increases fatty acid oxidation such that resistance to diet-induced obesity develops. This work suggests that using non-native pathways in higher organisms to explore and modulate metabolism may be a useful approach. PMID:19490907

Dean, Jason T.; Tran, Linh; Beaven, Simon; Tontonoz, Peter; Reue, Karen; Dipple, Katrina M.; Liao, James C.

2014-01-01

388

A 100 GHz Josephson mixer using resistively-shunted Nb tunnel junctions  

NASA Technical Reports Server (NTRS)

The authors describe preliminary mixer results using resistively shunted Nb/AlO(x)/Nb tunnel junctions in a 100-GHz waveguide mixer mount. The mixer utilizes robust, lithographically defined devices which have nonhysteretic I-V curves. A receiver temperature of 390 K (DSB) has been obtained with a conversion loss of -6.5 dB. The receiver's behavior agrees qualitatively with the behavior predicted by the resistively shunted junction model. Substantial improvements in performance are expected with the use of better-optimized shunted junctions, and numerical simulations suggest that, if devices with higher ICRN (critical current-normal state resistance) products can be obtained, Josephson effect mixers could be competitive with SIS mixers at high frequencies.

Schoelkopf, R. J.; Phillips, T. G.; Zmuidzinas, J.

1993-01-01

389

Superiority of radionuclide over oximetric measurement of left to right shunts.  

PubMed Central

In 100 children with suspected left to right shunts the ratio of pulmonary to systemic flow was measured both by oximetry and first pass radionuclide angiography. The pulmonary time activity curve from the radionuclide study was analysed by the method of gamma variate fits. There was strong correlation between the two techniques; weaker correlation was found when the shunt was at atrial rather than ventricular level. This difference can be explained only by problems with the oximetric rather than the radionuclide technique. Although there are important limitations to the radionuclide method, it is the more precise and less invasive of the two and is to be preferred when the accurate measurement of left to right shunts is required. PMID:3994867

Baker, E J; Ellam, S V; Lorber, A; Jones, O D; Tynan, M J; Maisey, M N

1985-01-01

390

Use of percutaneous endoscopy to place syringopleural or cystoperitoneal cerebrospinal fluid shunts: technical note.  

PubMed

The authors describe a technique for percutaneous endoscopic shunt placement to treat clinically symptomatic spinal cysts. Seven patients underwent the procedure--five with syringomyelia, one with a symptomatic perineurial cyst, and one with a large arachnoid cyst. In all patients the shunt was successfully placed, and clinical improvement occurred in six. In four patients the entire procedure was performed endoscopically, whereas in three conversion to an open surgical exposure was required for safe access of a syrinx cavity. Overall, however, the pleural or peritoneal catheter was successfully placed endoscopically in all seven patients. There were two cases of postoperative positional headaches of which one required valve revision. In one case the catheter migrated and required repositioning. Percutaneous endoscopic shunt placement appears feasible in appropriately selected patients. PMID:15871494

Guest, James D; Silbert, Lisa; Casas, Carlos E

2005-04-01

391

Active vibration control of a stiffened panel through application of negative capacitance shunts  

NASA Astrophysics Data System (ADS)

Shunted piezoelectric patches form an effective control mechanism for reducing vibrations of a mechanical system. One type of shunt, a negative capacitance circuit, is capable of suppressing vibration amplitude over a broad frequency range. Most previous work has focused on control of simple test structures such as beams and plates. This work studies the performance of the negative capacitance shunt connected to piezoelectric patches attached to a stiffened aircraft panel. The placement of the piezoelectric transducers is determined using a simplified finite element model of one bay of the panel. The numerical predictions are compared to experimental results for spatial average vibration for a point force input. The amount of control for increasing number of patches is also investigated. These results give a more accurate representation of the achievable performance in real world application.

Beck, Benjamin S.; Cunefare, Kenneth A.; Collet, Manuel; Ruzzene, Massimo

2011-03-01

392

A knot in the catheter--an unusual cause of ventriculo-peritoneal shunt blockage.  

PubMed

A 25-year-old woman, who was 25 weeks pregnant, underwent insertion of a VP shunt for hydrocephalus, secondary to a bithalamic glioma. Two months later, she represented with symptoms of raised intracranial pressure and MR scan revealed increased ventricular size. On exploration of the shunt, manometry with saline confirmed blockage of the catheter distal to the valve. On re-opening the abdominal wound, the peritoneal catheter was found to be knotted, 2 cm from the end. This segment of the catheter was replaced, with resolution of symptoms, post-operatively. The present case illustrates that a knot in the peritoneal catheter is an extremely rare cause of shunt malfunction. Possible mechanisms underlying it are discussed. PMID:15340821

Chopra, I; Gnanalingham, K; Pal, D; Peterson, D

2004-09-01

393

PI and fuzzy logic controllers for shunt Active Power Filter--a report.  

PubMed

This paper presents a shunt Active Power Filter (APF) for power quality improvements in terms of harmonics and reactive power compensation in the distribution network. The compensation process is based only on source current extraction that reduces the number of sensors as well as its complexity. A Proportional Integral (PI) or Fuzzy Logic Controller (FLC) is used to extract the required reference current from the distorted line-current, and this controls the DC-side capacitor voltage of the inverter. The shunt APF is implemented with PWM-current controlled Voltage Source Inverter (VSI) and the switching patterns are generated through a novel Adaptive-Fuzzy Hysteresis Current Controller (A-F-HCC). The proposed adaptive-fuzzy-HCC is compared with fixed-HCC and adaptive-HCC techniques and the superior features of this novel approach are established. The FLC based shunt APF system is validated through extensive simulation for diode-rectifier/R-L loads. PMID:21982358

P, Karuppanan; Mahapatra, Kamala Kanta

2012-01-01

394

Percutaneous Closure of the Acquired Gerbode Shunt Using the Amplatzer Duct Occluder in a 3-Month Old Patient  

PubMed Central

The Gerbode shunt, known as the left ventricle to the right atrial communication, is a rather rare finding, following surgical closure of septal defects. Even though the surgical closure is accepted as a treatment of choice, we report a successful percutaneous transcatheter closure of the Gerbode shunt in a 3-months old baby who weighed 3 kilograms. PMID:23882295

Lee, Sang Yun; Baek, Jae Suk

2013-01-01

395

THE ORIGIN OF IDEALITY FACTORS N > 2 OF SHUNTS AND SURFACES IN THE DARK IV CURVES OF SI SOLAR CELLS  

Microsoft Academic Search

So far, a general model for the explanation of non-linear shunts and edge currents, often showing ideality factors n > 2, has been missing. Non-linear shunts like scratches and edge currents are the major source of the recombination current of industrial crystalline silicon solar cells. Moreover, the reverse current of such cells behaves always linear or even superlinear instead of

O. Breitenstein; P. Altermatt; K. Ramspeck; A. Schenk

396

Intrapulmonary shunt after cardiopulmonary bypass: The use of vital capacity maneuvers versus off-pump coronary artery bypass grafting  

Microsoft Academic Search

Objectives: It has been proved in human subjects and animals that atelectasis is a major cause of intrapulmonary shunting and hypoxemia after cardiopulmonary bypass. Animal studies suggest that shunting can be prevented entirely by a total vital capacity maneuver performed before termination of bypass. This study aimed to test this theory in human subjects and to evaluate possible advantages of

Edda M. Tschernko; Anton Bambazek; Wilfried Wisser; Bernhard Partik; Ursula Jantsch; Klaus Kubin; Marek Ehrlich; Walter Klimscha; Michael Grimm; Franz P. Keznickl

2002-01-01

397

Reversal of Transjugular Intrahepatic Portosystemic Shunt (TIPS)Induced Hepatic Encephalopathy Using a Strictured Self-Expanding Covered Stent  

Microsoft Academic Search

Hepatic encephalopathy is a known complication following percutaneous transjugular intrahepatic portosystemic shunt (TIPS) placement. We describe herein a simple and effective strategy of TIPS revision by creating an intraluminal stricture within a self-expanding covered stent, which is deployed in the portosystemic shunt to reduce the TIPS blood flow. This technique was successful in reversing a TIPS-induced hepatic encephalopathy in our

Mitchell W. Cox; George D. Soltes; Peter H. Lin; Ruth L. Bush; Alan B. Lumsden

2003-01-01

398

Dual microcather-dual detachable coil technique in embolization for a congenital intrahepatic portosystemic venous shunt (IPSVS).  

PubMed

We report a 14-year-old boy with a large intrahepatic portosystemic venous shunt. The shunt seemed to be difficult to coil embolize because it was so large and short. However, it was successfully treated by coil embolization with a new dual microcatheter-dual detachable coil technique. PMID:23374114

Suzuki, Kazushi; Shimohira, Masashi; Hashizume, Takuya; Suzuki, Yosuke; Shibamoto, Yuta

2013-09-01

399

Use of transsplenic injection of agitated saline and heparinized blood for the ultrasonographic diagnosis of macroscopic portosystemic shunts in dogs.  

PubMed

We describe the use of ultrasonography-guided percutaneous splenic injection of agitated saline and heparinized blood for the diagnosis of portosystemic shunts (PSS) in 34 dogs. Agitated saline mixed with 1 ml of heparinized autologous blood was injected into the spleen of 34 sedated dogs under sonographic guidance. The transducer was then sequentially repositioned to visualize the portal vein, the caudal vena cava, and the right atrium through different acoustic windows. It was possible to differentiate between intrahepatic and extrahepatic shunts depending on the entry point of the microbubbles into the caudal vena cava. Portoazygos shunts and portocaval shunts could be differentiated based on the presence of microbubbles in the caudal vena cava and/or the right atrium. In one dog, collateral circulation due to portal hypertension was identified. In dogs with a single extrahepatic shunt, the microbubbles helped identify the shunting vessel. The technique was also used postoperatively to assess the efficacy of shunt closure. All abnormal vessels were confirmed by exploratory laparotomy or with ultrasonographic identification of the shunting vessel. Ultrasound-guided transsplenic injection of agitated saline with heparinized blood should be considered as a valuable technique for the diagnosis of PSS; it is easy to perform, safe, and the results are easily reproducible. PMID:21322395

Gómez-Ochoa, Pablo; Llabrés-Díaz, Francisco; Ruiz, Sergio; Corda, Andrea; Prieto, Saul; Sosa, Ivan; Gregori, Tommaso; Gascón, Manuel; Couto, Guillermo C

2011-01-01

400

Experimental rotordynamic coefficient results for: (a) a labyrinth seal with and without shunt injection and (b) a honeycomb seal  

E-print Network

been modified by (a) using swirl brakes, and (b) using shunt injection. In some cases, labyrinth seals have been replaced entirely by honeycomb seals. In shunt injection, the gas is taken from the diff-user or discharge volute, and injected...

Soto Azuaje, Elias Antonio

1997-01-01

401

Electrospun polyurethane as an alternative ventricular catheter and in vitro model of shunt obstruction.  

PubMed

Intracranial pressure and volume vary considerably between hydrocephalic patients, and with age, health and haemodynamic status; if left untreated, intracranial pressure rises and the ventricular system expands to accommodate the excess cerebrospinal fluid, with significant morbidity and mortality. Cerebrospinal fluid shunts in use today have a high incidence of failure with shunt obstruction being the most serious. Conventional proximal shunt catheters are made from poly(dimethyl)siloxane, the walls of which are perforated with holes for the cerebrospinal fluid to pass through. The limited range of catheters, in terms of material selection and flow distribution, is responsible in large part for their poor performance. In this study, we present an alternative design of proximal catheter made of electrospun polyether urethane, and evaluate its performance in the presence of glial cells, which are responsible for shunt blockage. The viability and growth of cells on catheter materials such as poly(dimethyl)siloxane and polyurethane in the form of cast films, microfibrous mats and porous sponges were studied in the presence of proteins present in cerebrospinal fluid after 48?h and 96?h in culture. The numbers of viable cells on each substrate were comparable to untreated poly(dimethyl)siloxane, both in the presence and absence of serum proteins found in cerebrospinal fluid. A cell culture model of shunt obstruction was developed in which cells on electrospun polyether urethane catheters were subjected to flow during culture in vitro, and the degree of obstruction quantified in terms of hydraulic permeability after static and perfusion culture. The results indicate that a catheter made of electrospun polyether urethane would be able to maintain cerebrospinal fluid flow even with the presence of cells for the time period chosen for this study. These findings have implications for the design and deployment of microporous shunt catheter systems for the treatment of hydrocephalus. PMID:25245779

Suresh, Supraja; Black, Richard A

2015-02-01

402

SPECTRUM CLASSIFICATION FOR EARLY FAULT DIAGNOSIS OF THE LP GAS PRESSURE REGULATOR BASED ON THE KULLBACK-LEIBLER KERNEL  

E-print Network

SPECTRUM CLASSIFICATION FOR EARLY FAULT DIAGNOSIS OF THE LP GAS PRESSURE REGULATOR BASED The present paper describes a frequency spectrum classi- fication method for fault diagnosis of the LP gas, such as polyno- mial or Gaussian kernels, or the conventional fault diagnosis method and Gaussian Mixture Model

Higuchi, Tomoyuki

403

75 FR 56093 - Eagle Rock Desoto Pipeline, LP; Notice of Motion for Extension of Rate Case Filing Deadline  

Federal Register 2010, 2011, 2012, 2013, 2014

...Commission [Docket No. PR09-1-002] Eagle Rock Desoto Pipeline, LP; Notice of Motion for Extension...Take notice that on September 8, 2010, Eagle Rock Desoto Pipeline, L.P. (Eagle Rock) filed a request to extend the date for...

2010-09-15

404

78 FR 48177 - Purdue Pharma L.P.; Withdrawal of Approval of a New Drug Application for Oxycontin  

Federal Register 2010, 2011, 2012, 2013, 2014

...No. FDA-2013-N-0883] Purdue Pharma L.P.; Withdrawal of Approval of a New Drug Application...Extended-Release Tablets, held by Purdue Pharma L.P. (Purdue), One Stamford Forum, Stamford...8-6-13; 8:45 am] BILLING CODE...

2013-08-07

405

75 FR 49926 - Arena Energy, L.P. v. Sea Robin Pipeline Company, LLC; Notice of Complaint  

Federal Register 2010, 2011, 2012, 2013, 2014

...Docket No. RP10-1045-000] Arena Energy, L.P. v. Sea Robin Pipeline Company, LLC; Notice of Complaint August 3, 2010...L.P. (Complainant) filed a formal complaint against Sea Robin Pipeline Company, LLC (Respondent) alleging that the...

2010-08-16

406

77 FR 25133 - Foreign-Trade Zone 126, Temporary/Interim Manufacturing Authority, Brightpoint North America L.P...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Manufacturing Authority, Brightpoint North America L.P. (Cell Phone Kitting and Distribution); Notice of Approval On March 2...behalf of Brightpoint North America L.P., to produce cell phone kits under FTZ procedures within FTZ 126--Site 23, in...

2012-04-27

407

76 FR 17180 - KLH Capital II, L.P.; Notice Seeking Exemption Under Section 312 of the Small Business Investment...  

Federal Register 2010, 2011, 2012, 2013, 2014

...SMALL BUSINESS ADMINISTRATION [License No. 04/04-0296] KLH Capital II, L.P...Small Business Administration (``SBA...107.730). KLH Capital, L.P., proposes...Associates of KLH Capital, L.P., as...Small Business Administration, 409 Third...

2011-03-28

408

78 FR 10128 - Expansion/Reorganization of Foreign-Trade Subzone 70T; Marathon Petroleum Company LP; Detroit, MI  

Federal Register 2010, 2011, 2012, 2013, 2014

...Expansion/Reorganization of Foreign-Trade Subzone 70T; Marathon Petroleum Company LP; Detroit, MI Pursuant to its authority...Site 1 of Subzone 70T and remove Site 3 of the subzone at the Marathon Petroleum Company LP refinery in Detroit, Michigan....

2013-02-13

409

75 FR 17706 - Flint Hills Resources, LP, Complainant v. Mid-America Pipeline Company, LLC, Respondent; Notice...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Energy Regulatory Commission [Docket No. OR10-11-000] Flint Hills Resources, LP, Complainant v. Mid-America Pipeline...Commerce Act, 49 U.S.C. App. 2, 3, 13, and 15 (1988), Flint Hills Resources, LP (Complainant) filed a complaint...

2010-04-07

410

76 FR 619 - Escalate Capital Partners SBIC I, L.P.; Notice Seeking Exemption Under Section 312 of the Small...  

Federal Register 2010, 2011, 2012, 2013, 2014

...SBIC I, L.P. proposes to provide debt security financing to LDR Holding Corporation, 4030 West Braker Lane, Suite 360, Austin...Partners, SBIC I, L.P., owns more than ten percent of LDR Holding Corporation. Therefore, this transaction is...

2011-01-05

411

Finite Gain lp Stabilization of Discrete-Time Linear Systems Subject to Actuator Saturation: the Case of p = 1  

E-print Network

Finite Gain lp Stabilization of Discrete-Time Linear Systems Subject to Actuator Saturation-time linear systems subject to actuator saturation, finite gain lp stabilization can be achieved by linear of actuator saturation and measurement and actuator noises (see [8], [1] and the references therein). More

Sontag, Eduardo

412

77 FR 45596 - Shell Energy North America (US), L.P. v. California Independent System Operator Corporation...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Energy Regulatory Commission [Docket No. EL12-88 -000] Shell Energy North America (US), L.P. v. California Independent...Commission) Rules of Practice and Procedure, 18 CFR 385.206, Shell Energy North America (US), L.P. (Complainant)...

2012-08-01

413

75 FR 19644 - West Oaks Energy NY/NE, LP; Supplemental Notice That Initial Market-Based Rate Filing Includes...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Regulatory Commission [Docket No. ER10-1030-000] West Oaks Energy NY/NE, LP; Supplemental Notice That Initial Market-Based...supplemental notice in the above-referenced proceeding of West Oaks Energy NY/NE LP's application for market-based rate...

2010-04-15

414

[Persistent pulmonary opacification as a sequela of portopulmonary shunt in portal vein thrombosis].  

PubMed

Portopulmonary venous anastomosis are a very rare complication of chronic liver diseases. We report on a patient with a cryptogenic liver cirrhosis and thrombosis of the portal vein who underwent antibiotic treatment because of recurrent pneumonias several times. Although treated successfully a pulmonal infiltrate persisted in further radiologic controls. By means of a velocity-encoded MRI a portopulmonary shunt of 30% of the cardiac output was assured. An operative correction with a distal splenorenal shunt was performed successfully. Former reports of portopulmonary anastomoses complicating chronic liver disease never were hemodynamically relevant. In the presented case, a portopulmonary anastomosis lead to recurrent pneumonias and a restrictive ventilatory disorder. PMID:9880823

Meyer, R G; Orth, T; Kreitner, K F; Schirmacher, P; Meyer zum Büschenfelde, K H; Gerken, G

1998-11-01

415

Incarceration of umbilical hernia after radiological insertion of a Denver peritoneovenous shunt.  

PubMed

We report a rare complication of incarceration of an umbilical hernia after Denver peritoneovenous shunt placement. A 50-year-old man presented with refractory ascites from liver cirrhosis. He also had an umbilical hernia. Because the ascites became uncontrollable, Denver peritoneovenous shunting was performed. The operation was successful and the ascites decreased. Ten days later, however, incarceration of the umbilical hernia occurred. A surgical repair was performed, but he died 2 days later. The cause of death was considered to be sepsis. PMID:23196823

Ohta, Kengo; Shimohira, Masashi; Hashizume, Takuya; Kawai, Tatsuya; Kurosaka, Kenichiro; Suzuki, Kazushi; Watanabe, Kenichi; Shibamoto, Yuta

2013-03-01

416

Intracranial pressure parameters in idiopathic normal pressure hydrocephalus patients treated with ventriculo-peritoneal shunts  

Microsoft Academic Search

Summary  Background. Although the mean intracranial pressure (ICP) is normal in patients with idiopathic normal pressure hydrocephalus (iNPH),\\u000a there could possibly be alterations in their single ICP waves.\\u000a \\u000a Method. Thirty-nine consecutive patients treated for iNPH with ventriculo-peritoneal shunts were followed prospectively with regard\\u000a to clinical and radiological findings. Changes in clinical state 12 months after shunt surgery were assessed as change

P. K. Eide

2006-01-01

417

Levoatriocardinal Vein: An Unusual Cause of Right-to-Left Shunting  

PubMed Central

We present a case demonstrating an anomalous vessel connecting the left brachiocephalic vein and the left superior pulmonary vein, found incidentally on computed tomography (CT) imaging. This pulmonary–systemic venous connection, known as a levoatriocardinal vein, is a rare anomaly. In previous descriptions, this vessel has typically been associated with left-to-right shunt. Here, we describe the magnetic resonance imaging (MRI) and CT findings in a case with right-to-left shunting through the anomalous vessel likely secondary to elevated right cardiac pressure.

Shet, Nilima; Maldjian, Pierre

2014-01-01

418

Temporary extravascular shunt for reconstruction of a superior vena cava invaded by a lung tumor.  

PubMed

Advanced central lung cancers can invade the superior vena cava (SVC). Although the indications for resection of the vessel remain controversial, it has been suggested that it increases the long-term survival of selected patients; however, little consensus has been reached regarding the optimal method of vascular reconstruction. While the SVC is often replaced during unprotected cross-clamp, the placement of a temporary venous shunt with a view to preserve the periprocedural safety and facilitate the postoperative management seems preferable. We describe an SVC reconstruction procedure using an autologous pericardial patch and placement of a temporary extravascular shunt via a lateral thoracotomy. PMID:25468109

Yotsukura, Masaya; Kinoshita, Tomonari; Kamiyama, Ikuo; Hato, Tai; Goto, Taichiro; Ohtsuka, Takashi; Yoshitake, Akihiro; Kudo, Mikihiko; Kohno, Mitsutomo

2014-12-01

419

Transcranial Doppler ultrasound identifies patients with right-to-left cardiac or pulmonary shunts.  

PubMed

We performed transcranial Doppler ultrasound (TCD) and transesophageal contrast echocardiography simultaneously in four patients. In one patient with a patent foramen ovale and another patient with pulmonary A-V fistulae, we detected micro air bubbles in the right middle cerebral artery three to five cardiac cycles after their appearance in the left atrium following intravenous injection of contrast. In two patients without right-to-left shunts, we did not detect air bubbles in the left atrium or middle cerebral artery following injection of contrast. These results show that TCD can identify patients with right-to-left cardiac or pulmonary shunts. PMID:1745345

Chimowitz, M I; Nemec, J J; Marwick, T H; Lorig, R J; Furlan, A J; Salcedo, E E

1991-12-01

420

Endoscopic third ventriculostomy versus ventriculoperitoneal shunt in pediatric patients: a decision analysis  

Microsoft Academic Search

Introduction  Uncertainty persists on the best treatment for patients with obstructive hydrocephalus: endoscopic third ventriculostomy (ETV)\\u000a or shunt, particularly in the younger age groups. We performed decision analysis for quality of life (QOL) outcomes comparing\\u000a these two procedures.\\u000a \\u000a \\u000a \\u000a Materials and methods  Frequency of outcome events for ETV was obtained from the Canadian Pediatric Neurosurgery Study Group (368 patients) and for\\u000a shunts from

James M. Drake; Abhaya V. Kulkarni; John Kestle

2009-01-01

421

Quality of life in obstructive hydrocephalus: endoscopic third ventriculostomy compared to cerebrospinal fluid shunt  

Microsoft Academic Search

Purpose  In the current literature, there are essentially no comparisons of quality of life (QOL) outcome after endoscopic third ventriculostomy\\u000a (ETV) and shunt in childhood hydrocephalus. Our objective was to compare QOL in children with obstructive hydrocephalus, treated\\u000a with either ETV or shunt.\\u000a \\u000a \\u000a \\u000a Methods  A cross-sectional survey was conducted at SickKids, Toronto of children between ages five and 18 years, with obstructive hydrocephalus

Abhaya V. Kulkarni; Sonya Hui; Iffat Shams; Ruth Donnelly

2010-01-01

422

Cost-consequence analysis of antibiotic-impregnated shunts and external ventricular drains in hydrocephalus.  

PubMed

OBJECT Despite multiple preventive strategies for reducing infection, up to 15% of patients with shunt catheters and 27% of patients with external ventricular drains (EVDs) may develop an infection. There are few data on the cost-effectiveness of measures to prevent hydrocephalus catheter infection from the hospital perspective. The objective of this study was to perform a cost-consequence analysis to assess the potential clinical and economic value of antibiotic-impregnated catheter (AIC) shunts and EVDs compared with non-AIC shunts and EVDs in the treatment of hydrocephalus from a hospital perspective. METHODS The authors used decision analytical techniques to assess the clinical and economic consequences of using antibiotic-impregnated shunts and EVDs from a hospital perspective. Model inputs were derived from the published, peer-reviewed literature. Clinical studies comparing infection rates and the clinical and economic impact of infections associated with the use of AICs and standard catheters (non-AICs) were evaluated. Outcomes assessed included infections, deaths due to infection, surgeries due to infection, and cost associated with shunt- and EVD-related infection. A subanalysis using only AIC shunt and EVD Level I evidence (randomized controlled trial results) was conducted as an alternate to the cumulative analysis of all of the AIC versus non-AIC studies (13 of the 14 shunt studies and 4 of the 6 EVD studies identified were observational). Sensitivity analyses were conducted to determine how changes in the values of uncertain parameters affected the results of the model. RESULTS In 100 patients requiring shunts, AICs may be associated with 0.5 fewer deaths, 71 fewer hospital days, 11 fewer surgeries, and $128,228 of net savings in hospital costs due to decreased infection. Results of the subanalysis showed that AICs may be associated with 1.9 fewer deaths, 1611 fewer hospital days, 25 fewer surgeries, and $346,616 of net savings in hospital costs due to decreased infection. The rate of decrease in infection with AIC shunts was shown to have the greatest impact on the cost savings realized with use of AIC shunts. In 100 patients requiring EVDs, AICs may be associated with 2.7 fewer deaths and 82 fewer hospital days due to infection. The relative risk of more severe neurological impairment was estimated to be 5.33 times greater with EVD infection. Decreases in infection with AIC EVDs resulted in an estimated $264,069 of net savings per 100 patients treated with AICs. Results of the subanalysis showed that AIC EVDs may be associated with 1.0 fewer deaths, 31 infection-related hospital days averted, and $74,631 saved per 100 patients treated with AIC EVDs. As was seen with AIC shunts, the rate of decrease in infection with AIC EVDs was shown to have the greatest impact on the cost savings realized with use of AIC EVDs. CONCLUSIONS The current value analysis demonstrates that evidence supports the use of AICs as effective and potentially cost-saving treatment. PMID:25380105

Edwards, Natalie C; Engelhart, Luella; Casamento, Eva M H; McGirt, Matthew J

2015-01-01

423

78 FR 34089 - Jordan Cove Energy Project, L.P.; Notice of Application  

Federal Register 2010, 2011, 2012, 2013, 2014

...Project, L.P.; Notice of Application Take notice that on May 21...No. CP13-483-000 an application under section 3 of the Natural...its liquefied state in two cryogenic storage tanks, and loading...more fully set forth in the application which is on file with...

2013-06-06

424

10. BOILER #16 (BUILDING L8) TO LEFT, L.P. AND H.P. ...  

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

10. BOILER #16 (BUILDING L8) TO LEFT, L.P. AND H.P. BOILER ROOMS (BUILDINGS L4 AND L2) TO RIGHT, AND STEPHENS SUBSTATION (BUILDING L6) IN BACKGROUND, FROM THE ROOF OF THE POWERHOUSE EXTENSION (BUILDING L5) - Portland General Electric Company, Station "L", 1841 Southeast Water Street, Portland, Multnomah County, OR

425

On Lp minimisation, instance optimality, and restricted isometry constants for sparse  

E-print Network

On Lp minimisation, instance optimality, and restricted isometry constants for sparse approximation.gribonval@inria.fr Abstract: We extend recent results regarding the restricted isometry constants (RIC) and sparse recovery than exactly sparse signals. We begin by showing that the robust null space property used in [3

Paris-Sud XI, Université de

426

Explosive Solutions of Stochastic Reaction-Diffusion Equations in Mean Lp  

E-print Network

Explosive Solutions of Stochastic Reaction-Diffusion Equations in Mean Lp -Norm Pao-Liu Chow, Parabolic It^o equations, It^o's Formula, Positive Solutions, Blow-up of solutions, Explosions. 1 #12 this phenomenon is manifested as the explosion in combustion, reaction diffusion and branching diffusion problems

427

75 FR 71715 - Accreditation and Approval of Saybolt LP, as a Commercial Gauger and Laboratory  

Federal Register 2010, 2011, 2012, 2013, 2014

...SUMMARY: Notice is hereby given that, pursuant to 19 CFR 151.12 and 19 CFR 151.13, Saybolt LP, 3915 Saw Mill Run Blvd., Pittsburgh, PA 15227, has been approved to gauge and accredited to test petroleum and petroleum...

2010-11-24

428

COS FUV Detector Response to New HV Management System at LP3 {LENA4}  

NASA Astrophysics Data System (ADS)

This program uses a series of 205s WAVECALS and 60s DCE dumps to exercise the new HV Management System. We first ramp to the Maximum HV for Both Segment FUVA/FUVB = 178/175, we then transition to the minimum HV {A/B = 167/163} using the new HV management system, then transition back to the Maximum HV. The WAVECAL exposures at the Maximum HV will be taken with G160M/1611 {C1611} and the minimums are taken with G160M/1623 {C1623}. The CENWAVE change is required to allow time for the HV change. The sequence is repeated with FUVA ON {FUVB OFF}, and then with FUVB ON {FUVA OFF}. DCE Dumps are included before and after each WAVECAL.All exposures in the program should execute at the LP3 position, using the ALTERNATE lifetime position.This program will use a special HV Table with the following changes to the normal HV/Aperture table:CENWAVE Lifetime Position HVA/HVB--------------------------1611 Alternate {LP3} 178/1751623 Alternate {LP3} 167/163LP3 FUV aperture positions and SIAF file updates are not absolutely required, as these are all internals, but they are desired.

Penton, Steven

2013-10-01

429

Rational Blanchfield forms, S-equivalence, and null LP-surgeries  

E-print Network

Rational Blanchfield forms, S-equivalence, and null LP-surgeries Delphine Moussard Abstract Null) composed of a rational homology sphere M and a null-homologous knot K in M. They are defined as replacements of null-homologous rational homology handlebodies of M \\ K by other such handle- bodies

Paris-Sud XI, Université de

430

75 FR 3244 - Accreditation and Approval of Saybolt LP, as a Commercial Gauger and Laboratory  

Federal Register 2010, 2011, 2012, 2013, 2014

...SUMMARY: Notice is hereby given that, pursuant to 19 CFR 151.12 and 19 CFR 151.13, Saybolt LP, 21730 S. Wilmington Ave., Suite 201, Carson, CA 90810, has been approved to gauge and accredited to test petroleum and petroleum products in...

2010-01-20

431

76 FR 64962 - Accreditation and Approval of SAYBOLT LP, as a Commercial Gauger and Laboratory  

Federal Register 2010, 2011, 2012, 2013, 2014

...SUMMARY: Notice is hereby given that, pursuant to 19 CFR 151.12 and 19 CFR 151.13, Saybolt LP, 1809 Magnolia Ave, Port Neches, TX 77651, has been approved to gauge and accredited to test petroleum and petroleum products, organic...

2011-10-19

432

Intensive Lifestyle Modification Reduces Lp-PLA2 in Dyslipidemic HIV/HAART Patients  

PubMed Central

Patients with dyslipidemia associated with HIV-1 infection and highly active antiretroviral therapy (HAART) have elevated levels of Lp-PLA2 and CCL5/RANTES, which may increase risk of cardiovascular disease. Purpose This study aimed to determine whether an intensive diet and exercise (D/E) program, independently or combined with fenofibrate or niacin, could reduce Lp-PLA2 or RANTES. Methods Hypertriglyceridemic HIV patients on stable HAART (n=107) were randomized to one of five interventions: 1) Usual Care (UC); 2) D/E with placebos; 3) D/E with fenofibrate and placebo; 4) D/E with niacin and placebo; or 5) D/E with fenofibrate and niacin for 24 weeks. Lp-PLA2 and RANTES concentrations were measured in fasting plasma samples at baseline and post-intervention. General linear models were used to compare Lp-PLA2 and RANTES levels between the five groups post-intervention, controlling for baseline levels, age, BMI, CD4+ T-cell count, viral load, duration of infection, and HAART. Results At baseline, fasting plasma Lp-PLA2 (388.5 ± 127.5 ng/mL) and RANTES (43.8 ± 25.5 ng/mL) levels were elevated when compared to healthy controls. Post-treatment Lp-PLA2 mass was lower in patients who received D/E only (323.0 ± 27.2 ng/mL), D/E plus fenofibrate (327.2 ± 25.9 ng/mL) and D/E plus niacin (311.1 ± 27.8 ng/mL) when compared to patients receiving UC (402.2 ± 25.3 ng/mL). RANTES concentrations were not significantly affected by any intervention. Conclusions Elevated plasma Lp-PLA2 mass can be reduced by an intensive diet and exercise program in patients with HIV/HAART-associated dyslipidemia. RANTES is elevated but is not reduced by lifestyle modification, fenofibrate or niacin. PMID:23299761

Wooten, Joshua S.; Nambi, Preethi; Gillard, Baiba K.; Pownall, Henry J.; Coraza, Ivonne; Scott, Lynne W.; Nambi, Vijay; Ballantyne, Christie M.; Balasubramanyam, Ashok

2013-01-01

433

Molecular characterization and structural instability of the industrially important composite metabolic plasmid pLP712.  

PubMed

The widely used plasmid-free Lactococcus lactis strain MG1363 was derived from the industrial dairy starter strain NCDO712. This strain carries a 55.39 kb plasmid encoding genes for lactose catabolism and a serine proteinase involved in casein degradation. We report the DNA sequencing and annotation of pLP712, which revealed additional metabolic genes, including peptidase F, d-lactate dehydrogenase and ?-keto acid dehydrogenase (E3 complex). Comparison of pLP712 with other large lactococcal lactose and/or proteinase plasmids from L. lactis subsp. cremoris SK11 (pSK11L, pSK11P) and the plant strain L. lactis NCDO1867 (pGdh442) revealed their close relationship. The plasmid appears to have evolved through a series of genetic events as a composite of pGdh442, pSK11L and pSK11P. We describe in detail a scenario by which the metabolic genes relevant to the growth of its host in a milk environment have been unified on one replicon, reflecting the evolution of L. lactis as it changed its biological niche from plants to dairy environments. The extensive structural instability of pLP712 allows easy isolation of derivative plasmids lacking genes for casein degradation and/or lactose catabolism. Plasmid pLP712 is transferable by transduction and conjugation, and both of these processes result in significant molecular rearrangements. We report the detailed molecular analysis of insertion sequence element-mediated genetic rearrangements within pLP712 and several different mechanisms, including homologous recombination and adjacent deletion. Analysis of the integration of the lactose operon into the chromosome highlights the fluidity of the MG1363 integration hotspot and the potential for frequent movement of genes between plasmids and chromosomes in Lactococcus. PMID:23023974

Wegmann, Udo; Overweg, Karin; Jeanson, Sophie; Gasson, Mike; Shearman, Claire

2012-12-01

434

77 FR 42353 - Ascent Venture Partners IV-A, L.P., License No. 01/01-0404; Notice Seeking Exemption Under...  

Federal Register 2010, 2011, 2012, 2013, 2014

...SMALL BUSINESS ADMINISTRATION Ascent Venture Partners IV-A, L.P., License No...Interest Notice is hereby given that Ascent Venture Partners IV-A, L.P., 255 State...Regulations (13 CFR 107.730). Ascent Venture Partners IV-A, L.P. proposes...

2012-07-18

435

76 FR 76802 - Riverside Micro-Cap Fund II, L.P.; Notice Seeking Exemption Under Section 312 of the Small...  

Federal Register 2010, 2011, 2012, 2013, 2014

...License No. 02/02-0646] Riverside Micro-Cap Fund II, L.P.; Notice Seeking...Interest Notice is hereby given that Riverside Micro-Cap Fund II, L.P., 45 Rockefeller...Regulations (13 CFR 107.730). Riverside Micro-Cap Fund II, L.P. proposes to...

2011-12-08

436

77 FR 7655 - Riverside Micro-Cap Fund II, L.P.; Notice Seeking Exemption Under Section 312 of the Small...  

Federal Register 2010, 2011, 2012, 2013, 2014

...License No. 02/02-0646] Riverside Micro-Cap Fund II, L.P.; Notice Seeking...Interest Notice is hereby given that Riverside Micro-Cap Fund II, L.P., 45 Rockefeller...Regulations (13 CFR 107.730). Riverside Micro-Cap Fund II, L.P. proposes to...

2012-02-13

437

77 FR 70812 - United States v. Star Atlantic Waste Holdings, L.P., Veolia Environnement S.A. and Veolia ES...  

Federal Register 2010, 2011, 2012, 2013, 2014

...JUSTICE Antitrust Division United States v. Star Atlantic Waste Holdings, L.P., Veolia...Columbia in United States of America v. Star Atlantic Waste Holdings, L.P., Veolia...alleging that the proposed acquisition by Star Atlantic Waste Holdings, L.P. of...

2012-11-27

438

Fibrous capsule formation of the peritoneal catheter tip in ventriculoperitoneal shunt: Two case reports  

PubMed Central

Background: A fibrous capsule formation of a peritoneal catheter tip has not previously been researched as a complication of ventriculoperitoneal (VP) shunts. Case Description: Two adult patients who had undergone a VP shunt for communicative hydrocephalus following subarachnoid hemorrhage caused by a ruptured aneurysm have been identified with malfunction of the VP shunt system by mild disturbance of consciousness and gait disturbance or loss of appetite. Hydrocephalus was diagnosed by computed tomography and the obstruction of the peritoneal catheter was revealed by shuntgraphy. Laparoscopy was performed and the peritoneal catheter tips were obstructed by fibrous white capsules that covered them. One was a thin membranous capsule like a stocking with two small endoluminal granulomas of the peritoneal catheter, and other one was a fibrous glossy white capsule like a sock. These fibrous capsules were excised by laparoscopy forceps without the conversion to a new peritoneal catheter. Following the procedure, the shunt functioned normally. The pathological diagnoses were peritoneum with foreign body reaction or hyalinization of membranous tissue surrounded by fibrous tissue. Conclusion: These fibrous capsules might be formed by the peritoneal reaction to cerebrospinal fluid as a foreign material. As such, a periodic medical check should be scheduled since a fibrous capsule of the peritoneal catheter tip might be formed again. PMID:25422787

Kano, Tomoaki

2014-01-01

439

Optimum Size and Location of Shunt Capacitors for Reduction of Losses on Distribution Feeders  

Microsoft Academic Search

New generalized procedures are developed for optimizing the net savings associated with reduction of power and energy losses through shunt capacitor placement on primary distribution feeders. These procedures are applied to realistic problems to facilitate their immediate use by the electric utility distribution system designer. It is shown that a basic principle, called here \\

J. J. Grainger; S. H. Lee

1981-01-01

440

BYPASS SYSTEM FOR SHUNTING OF ELECTROMAGNETS FOR ACCELERATORS AND STORAGE RINGS  

E-print Network

BYPASS SYSTEM FOR SHUNTING OF ELECTROMAGNETS FOR ACCELERATORS AND STORAGE RINGS O. Belikov, A the coil of electromagnet. The device developed allows both recuperation of the taken energy to the main power source of the electromagnet and energy dump to a ballast load. The bypass module is remotely

Kozak, Victor R.

441

Model for Calculating Electrolytic Shunt Path Losses in Large Electrochemical Energy Conversion Systems  

NASA Technical Reports Server (NTRS)

Generalized analysis and solution techniques were developed to evaluate the shunt power losses in electrochemical systems designed with a common or circulating electrolyte supply. Sample data are presented for a hypothetical bulk energy storage redox system, and the general applicability of the analysis technique is discussed.

Prokopius, P. R.

1976-01-01

442

Stimulation by propylthiouracil of the hexose monophosphate shunt in human polymorphonuclear leucocytes during phagocytosis.  

PubMed

The effect of propylthiouracil on glucose metabolism in human polymorphonuclear leucocytes was studied. At a therapeutically achievable concentration (0.1 mM), propylthiouracil stimulated hexose monophosphate shunt activity in normal leucocytes during phagocytosis but not in resting cells. However, in the presence of hydrogen peroxide it stimulated hexose monophosphate shunt activity in resting cells, and in the soluble fraction when reduced glutathione and reduced nictotinamide adenine dinucleotide phosphate (NADPH) were also present. Propylthiouracil had nor effect on glucose-1-C oxidation in either phagocytosing or resting leucocytes obtained from two male patients with chronic granulomatous disease. Stimulation of the hexose monophosphate shunt activity in normal leucocytes during phagocytosis also was demonstrated with methimazole, thiouracil and thiourea, but not with adenine, uracil or urea. There was an apparent minimal common structure requirement in thriourea. Propylthiouracil had no effect on phagocytosis, formate oxidation, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase or catalase activities. Thus, the stimulation of the hexose monophosphate shunt activity by propylthiouracil is dependent on hydrogen peroxide and is best explained by its stimulation or participation in the glutathione cycle. PMID:1201238

Tsan, M F; McIntyre, P A

1975-10-01

443

Candida parapsilosis meningitis associated with shunt infection in an adult male.  

PubMed

Candida parapsilosis is a very rare cause of meningitis. Though several cases have now been reported in neonates and children, only one has been described in an adult. We report on a 55-year-old male that was admitted due to altered mental status. He had recent sinus drainage and polypectomy, craniotomy with drainage of brain abscess, and ventriculo-peritoneal shunt placement. On admission, imaging studies showed no evidence of shunt dysfunction but did reveal extensive white matter decreased attenuation. Microscopic examination of the first 10 daily cerebrospinal fluid (CSF) cultures revealed yeast. Flucytosine and liposomal amphotericin B were started and externalization of shunt was performed on day 3. On day 8, CSF culture from admission grew C. parapsilosis; fluconazole was added. On day 10, daily CSF still showed yeast and cultures consistently grew C. parapsilosis. Shunt was removed and bilateral ventriculostomy drains were inserted. CSF after procedure as well as at follow-up examinations throughout his 3-month hospitalization were negative for yeast. Extended treatment with flucytosine and fluconazole was initiated. At 8-month follow-up, successful treatment of C. parapsilosis infection without recurrence was confirmed. This case underscores the need for suspicion of C. parapsilosis as a cause of meningitis after invasive surgeries in adults. PMID:20022423

Bagheri, Farshad; Cervellione, Kelly L; Maruf, Mohammad; Marino, William; Santucci, Thomas

2010-04-01

444

Transjugular Intrahepatic Portosystemic Shunt for the Treatment of Portal Hypertension in Noncirrhotic Patients with Portal Cavernoma  

PubMed Central

Background. The purpose of this study was to evaluate the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) placement in the management of portal hypertension in noncirrhotic patients with portal cavernoma. Methods. We conducted a single institution retrospective analysis of 15 noncirrhotic patients with portal cavernoma treated with TIPS placement. 15 patients (4 women and 11 men) were evaluated via the technical success of TIPS placement, procedural complications, and follow-up shunt patency. Results. TIPS placement was technically successful in 11 out of 15 patients (73.3%). Procedure-related complications were limited to a single instance of hepatic encephalopathy in one patient. In patients with successful shunt placement, the portal pressure gradient decreased from 25.8 ± 5.7 to 9.5 ± 4.2?mmHg (P < 0.001). TIPS dysfunction occurred in two patients during a median follow-up time of 45.2 months. Revision was not performed in one patient due to inadequate inflow. The other patient died of massive gastrointestinal bleeding in a local hospital. The remaining nine patients maintained functioning shunts through their last evaluation. Conclusions. TIPS is a safe and effective therapeutic treatment for noncirrhotic patients with symptomatic portal hypertension secondary to portal cavernoma. PMID:24868203

Luo, Xuefeng; Zhou, Biao; Yao, Denghua; Ma, Huaiyuan; Jiang, Mingshan; Zhang, Hailong; Li, Xiao

2014-01-01

445

Staging of portal hypertension and portosystemic shunts using dynamic nuclear medicine investigations  

Microsoft Academic Search

lation time between right heart and liver (RHLT). LTT for each lobe was used to evaluate the early portal hypertension. RHLT is useful in cirrhosis to detect liver areas missing portal inflow. We calculated the classical per-rectal portal shunt index (PRSI) at PRPS and the hepatic perfusion index (HPI) at LAS. RESULTS: The normal LTT value was 24 ± 1

Mircea Dragoteanu; Ioan A Balea; Liliana A Dina; Cecilia D Piglesan; Ioana Grigorescu; Stefan Tamas; Sabin O Cotul

2008-01-01

446

Alzheimer's disease comorbidity in normal pressure hydrocephalus: prevalence and shunt response  

Microsoft Academic Search

The clinical impact of Alzheimer's disease pathology at biopsy was investigated in 56 cognitively impaired patients undergoing shunt surgery for idiopathic normal pressure hydrocephalus (NPH). Cognition was measured by means of the global deterioration scale (GDS), the mini mental status examination (MMSE) and a battery of six psychometric tests. Gait was assessed using objective measurements of velocity and the ambulatory

J Golomb; J Wisoff; D C Miller; I Boksay; A Kluger; H Weiner; J Salton; W Graves

2000-01-01

447

Outcome of shunt operation on urinary incontinence in normal pressure hydrocephalus predicted by lumbar puncture  

Microsoft Academic Search

Bladder function in four patients with normal pressure hydrocephalus, one with dementia of Alzheimer type and five patients with multi-infarct dementia was studied by history and urodynamic tests (cystometry and Bor's ice water test). The bladder hyperactivity could be temporarily improved by a lumbar puncture and removal of 50 ml CSF and later abolished by a shunt operation in patients

J Ahlberg; L Norlén; C Blomstrand; C Wikkelsö

1988-01-01

448

Improved results with selective distal splenorenal shunt in a highly selected patient population. A prospective study.  

PubMed Central

In a 5-year period 299 patients were admitted to the Heinz-Kalk Hospital with bleeding esophageal varices. Patients with acute bleeding were treated with endoscopic sclerotherapy. Sessions were performed as many times as needed for each individual case. One hundred seventy-eight patients in Child-Pugh class C were excluded from surgical treatment; the remaining 121 patients (Child AB) were selected using the following criteria: liver volume (ultrasound) between 1000 to 2500 ml, portal perfusion (sequential scintigraphy) more than 30%, no activity or progression of liver disease proved by biopsy, no stenosis of the hepatic arteries, and suitable anatomy to perform the Warren shunt. Only 32 patients fulfilled these criteria. In seven of these cases the shunt was technically impossible to perform. Operative mortality rate was 8% and the late mortality rate was 12%. No history of rebleeding, encephalopathy, and/or shunt thrombosis was recorded. Five-year survival rate, according to the method of Kaplan-Meier was 75%. We conclude that the Warren shunt is the treatment of choice for elective management of bleeding esophageal varices. The postoperative results can be improved with strict selection using the above criteria. The preoperative use of sclerotherapy has a positive influence. Prophylactic management to prevent encephalopathy is also recommended. PMID:2787971

Paquet, K J; Mercado, M A; Koussouris, P; Kalk, J F; Siemens, F; Cuan-Orozco, F

1989-01-01

449

Variable sampling frequency in iterative learning current Control for Shunt Active Filter in aircraft power systems  

Microsoft Academic Search

This paper investigates the feasibility of an Iterative Leaning current Control (ILC) with variable sampling frequency to realize a 3-phase Shunt Active Filter (SAF) used for harmonic compensation in new generation aircrafts, where a Variable Speed Variable-Frequency (VSVF) power system, typically between 360 and 900Hz, is nowadays used. Due to the high supply frequency, such applications are particularly demanding for

Pericle Zanchetta; Marco Degano; Junyi Liu; Paolo Mattavelli

2011-01-01

450

Control of a multi-level active shunt power filter for More Electric Aircraft  

Microsoft Academic Search

The proposed increase of power electronic subsystems for More Electrical Aircraft (MEA) brings severe challenges to aircraft power distribution. Current aircraft power systems work at a fundamental frequency of 400 Hz while proposed AC MEA power networks for next generation aircrafts will have a fundamental frequency which varies most probably between 360 and 900 Hz. An active shunt filter (ASF)

Milijana Odavic; Mark Sumner; Pericle Zanchetta

2009-01-01

451

Control Design and Implementation for High Performance Shunt Active Filters in Aircraft Power Grids  

Microsoft Academic Search

This paper presents the design and implementation of a Shunt Active Filter (SAF) for aircraft power networks using an accurate wide-band current control method based on Iterative Learning Control (ILC). The SAF control system is designed to compensate harmonic currents, with a 400 Hz supply voltage. This work introduces useful design strategies to increase the error-decay speed and improve the

Junyi Liu; Pericle Zanchetta; Marco Degano; Elisabetta Lavopa

2012-01-01

452

Comparison of models for subtractive and shunting lateral-inhibition in receptor-neuron fields  

Microsoft Academic Search

Two types of neuronal lateral inhibition in one-dimensional fields of receptors and neurons are considered. The first type, which has been demonstrated in the eye of Limulus, is called subtractive inhibition (SI): it assumes that neuronal activity depends on the difference between the total excitation and inhibition. The second type is called shunting inhibition (SHI): it assumes that inhibitory influences

G. G. Furman; Murray Hi

1965-01-01

453

Negative capacitance shunt damping system with optimized characteristics for use with piezoelectric transducers  

NASA Astrophysics Data System (ADS)

For ecologic sustainability and decreasing reserves of fossile energy sources, fuel efficiency is a major concern especially for passenger aircraft. Therefore, lightweight structures made from carbon fiber plastics offer great potential. But when used for panel-like structures, they have the disadvantage of lower damping and coincidence frequencies compared to conventional differential metal constructions. Both aspects lead to an increased vibration level and by this a higher noise radiation. Because of this, special noise and vibration treatment is needed to ensure passenger cabin comfort. Besides passive damping and active structural acoustic control (ASAC), piezoelectric shunt damping is investigated. Due to its broadband performance, the negative capacitance shunt can be used for multimode systems with varying eigenfrequencies. These shunts are usually built with operational amplifiers and passive components as resistors and capacitors. This setup is sufficient for laboratory tests at low excitation levels. In fact, it is not capable of accessing the full voltage amplitude of common piezoelectric transducers, because most operational amplifiers only deliver +/-15V maximum output voltage. Therefore an improved setup is presented in this paper, which addresses the specific voltage requirements of a common piezoelectric transducer to achieve best performance. It comprises a tailored power source and an appropriate concept for the negative capacitance shunt hardware. This new hardware only uses standard operational amplifiers together with a high voltage power amplifier to cover the whole operating range of a piezoelectric transducer. A demonstrator board is developed and experimentally investigated at a test structure. Finally, the results are compared to a conventional setup.

Pohl, Martin

2014-03-01

454

Computer simulation of magnetization-controlled shunt reactors for calculating electromagnetic transients in power systems  

SciTech Connect

A computer procedure for simulating magnetization-controlled dc shunt reactors is described, which enables the electromagnetic transients in electric power systems to be calculated. It is shown that, by taking technically simple measures in the control system, one can obtain high-speed reactors sufficient for many purposes, and dispense with the use of high-power devices for compensating higher harmonic components.

Karpov, A. S. [St Petersburg State Polytechnical University, JSC 'System Operator of the United Power System', Leningradskoe RDU (Russian Federation)] [St Petersburg State Polytechnical University, JSC 'System Operator of the United Power System', Leningradskoe RDU (Russian Federation)

2013-01-15

455

Liquid breathing - Prevention of pulmonary arterial-venous shunting during acceleration.  

NASA Technical Reports Server (NTRS)

Dependent pulmonary atelectasis, arterial-venous shunting, and downward displacement of the heart caused by the gravitational-inertial force environment were prevented in dogs breathing oxygenated liquid fluorocarbon in a whole-body water-immersion respirator. Partial closure of the major airways during part of the expiratory phase of liquid respiration was a significant problem initially but was minimized in subsequent studies.

Sass, D. J.; Ritman, E. L.; Caskey, P. E.; Banchero, N.; Wood, E. H.

1972-01-01

456

Effect of the Portacaval Shunt on Reperfusion Injury after 65% Hepatectomy in Pigs  

Microsoft Academic Search

Background: Portal flow diversion by portacaval shunts (PCS) has been shown to prevent primary graft nonfunction in liver transplantation using small-for-size grafts. In this study, we examine whether PCS can improve reperfusion injury after major hepatectomy in pigs. Materials and Methods: In 14 pigs, a partial PCS was constructed following 65% hepatectomy and 1 h of inflow ischemia. During 24

C. Farantos; N. Arkadopoulos; K. Theodoraki; G. Kostopanagiotou; K. Katis; K. Tzavara; I. Andreadou; K. Dimopoulou; E. Hatzoudi; T. Sidiropoulou; I. Skalkidis; A. Paphiti; V. Smyrniotis

2008-01-01

457

Study of Anterior Chamber Aqueous Tube Shunt by Fourier-Domain Optical Coherence Tomography  

PubMed Central

Purpose. This cross-sectional, observational study used Fourier-domain optical coherence tomography (OCT) to examine the position, patency, and the interior entrance site of anterior chamber (AC) aqueous tube shunts. Methods. The OCT, slitlamp biomicroscopy, and gonioscopy findings of 23 eyes of 18 patients with AC shunts were collected and compared. Results. OCT images demonstrated the shunt position and patency in all 23 eyes, and the details of the AC entrance in 16 eyes. The position of the tube varied, with the majority (14/23) on the surface of the iris. The exact position of the AC entrance relative to Schwalbe's line (SL) could be determined in 9 eyes (posterior to SL in 7 eyes, anterior in 2 eyes). At the AC entrance, growth of fibrous scar tissue was present between the tube and the corneal endothelium in all 16 eyes in which the entrance could be clearly visualized. It's a new finding that could not be visualized by slitlamp examination or lower resolution OCT. Conclusion. Compared to slitlamp examination, Fourier-domain OCT of AC tube shunts provided more detailed anatomic information regarding the insertion level relative to SL, scar tissue between the tube and the corneal endothelium, and patency of the tube opening. PMID:22778909

Jiang, Chunhui; Li, Yan; Huang, David; Francis, Brian A.

2012-01-01

458

Outcome of endoscopic third ventriculostomy and Chhabra shunt system in noncommunicating non-tumor childhood hydrocephalus  

PubMed Central

Background: Endoscopic third ventriculostomy (ETV) the main alternative to ventriculoperitoneal shunt (VPS) is just beginning to have a foothold in West Africa. It provides a great opportunity for a hydrocephalic child to be shunt free. The purpose of this paper is to compare outcome following ETV and VPS (using the cheap Chhabra shunt) in children with noncommunicating non-tumoral hydrocephalus in an environment where late presentation is the norm. Materials and Methods: Sixty-three pediatric patients (< 6 years) with hydrocephalus who underwent a VPS or ETV at our hospital were included in this study. The study period was of 30 months (January 2006 till June 2008). Clinically successful outcome was defined as no event occurring during or after surgery that resulted in an alternate surgical procedure, or significant post-operative complication that includes death. All complications related to the procedures were also analyzed. Results: The outcome of surgical intervention was not significantly related to the gender, age of the patient at surgery, or type of surgery. The post-operative complication rate was similar in both groups. Conclusions: The clinical outcome of ETV is comparable to that of VPS, with the added benefit of no shunt-related problems; and being a short procedure, patient anesthesia and operation time, hospital stay, and cost are significantly reduced. We consider ETV to be the procedure of choice for the treatment of noncommunicating nontumoral hydrocephalus in the pediatric population. PMID:21887185

Idowu, O. E.; Falope, L. O.; Idowu, A. T.

2009-01-01

459

Prenatal ultrasound guided percutaneous shunts for obstructive uropathy and thoracic disease  

Microsoft Academic Search

The authors reviewed the status of closed ultrasound-guided fetal therapy using a pigtail shunt to create vesicoamniotic or thoracoamniotic decompression of the fluid-filled space. This review includes published and textbook reports of in utero therapy for bladder obstruction, pleural effusion, and macrocystic adenomatoid malformation from 1985 through 2002. For fetuses affected by lower urinary tract obstruction, the key component is

R. Douglas Wilson; Mark P Johnson

2003-01-01

460

A Three-Wire Insulator-Shunting Model for High-Temperature Thermocouple Errors  

Microsoft Academic Search

An equivalent circuit and computer solution were formulated for describing the output of a metal-sheathed bifilar thermocouple degraded by insulator shunting at high temperatures. This steady-state equivalent circuit model can be used for prediction of errors in thermocouple calibrations, for examining the effects of changes in thermocouple configuration or materials properties, and for examining methods for interrogation or surveillance of

J. R. McDearman; J. M. Googe; R. L. Shepard

1971-01-01

461

Is Chryseobacterium indologenes a shunt-lover bacterium? A case report and review of the literature.  

PubMed

Chryseobacterium indologenes is a non-fermentative Gram-negative bacillus formerly belonging to the Flavobacterium genus. It is widely found in water and soil, also on wet surfaces of the hospital environment. It rarely causes infections and is usually associated with altered immune status or indwelling devices. We present a case of ventriculoperitoneal shunt infection caused by C. indologenes in a premature pediatric patient. A six-month-old male infant with congenital hydrocephalus and ventriculoperitoneal shunt was admitted with complaints of irritability, high fever and projectile vomiting. He was diagnosed as suffering from meningitis based on the clinical symptoms and laboratory findings of cerebrospinal fluid. The ventriculoperitoneal shunt was externalized and cerebrospinal fluid samples were sent for bacterial cultures. The isolated bacterium was identified as C. indologenes by conventional methods and the BD Phoenix™ 100 (Becton Dickinson, MD, USA) fully automated microbiology system. Antimicrobial susceptibility testing was performed by the microdilution method and Kirby-Bauer's disk diffusion method according to the Clinical and Laboratory Standards Institute guidelines. The isolate was found susceptible to ciprofloxacin, levofloxacin, cefoperazone and trimethoprim-sulfamethoxazole, while it was resistant to amikacin, aztreonam, cefepime, ceftazidime, gentamicin, imipenem and ticarcillin-clavulanic acid. The treatment was started with trimethoprim-sulfamethoxazole and cefoperazone-sulbactam The ventriculoperitoneal shunt was then removed. The patient was fully healed after two weeks and discharged. Central nervous system infection is a rare form of C. indologenes infections. The case presented herein may make a useful contribution to the existing literature. PMID:24335463

Ozcan, Nida; Dal, Tuba; Tekin, Alicem; Kelekci, Selvi; Can, Sukran; Ezin, Ozgur; Kandemir, Idris; Gul, Kadri

2013-12-01

462

Screening for Ventricular Shunt Function in Children with Hydrocephalus Secondary to Meningomyelocele  

Microsoft Academic Search

Objective: To evaluate the current method of using computerized tomographic (CT) scans to screen for ventricular shunt failure in children who have hydrocephalus. Design: Retrospective review of 112 randomly selected charts. Patients: Children diagnosed with infantile hydrocephalus secondary to meningomyelocele, who were treated at the Andrew J. Kirch Developmental Services Center since 1978. Results: One hundred and twelve patients were

Gregory S. Liptak; Heidi M. Bolander; Kristen Langworthy

2001-01-01

463

Transjugular intrahepatic portosystemic shunt for palliative treatment of portal hypertension secondary to portal vein tumor thrombosis  

Microsoft Academic Search

AIM: To evaluate the palliative therapeutic effects of transjugular intrahepatic portosystemic shunt (TIPS) in portal vein tumor thrombosis (PVTT) complicated by portal hypertension. METHODS: We performed TIPS for 14 patients with PVTT due to hepatocellular carcinoma (HCC). Of the 14 patients, 8 patients had complete occlusion of the main portal vein, 6 patients had incomplete thrombosis, and 5 patients had

Zai-Bo Jiang; Hong Shan; Xin-Ying Shen; Ming-Sheng Huang; Zheng-Ran Li; Kang-Shun Zhu; Shou-Hai Guan

464

Focal nodular hyperplasia in association with spontaneous intrahepatic portosystemic venous shunt.  

PubMed

We report a case of focal nodular hyperplasia in an adolescent with a spontaneous intrahepatic portosystemic venous shunt. Diagnosis was established by duplex and color Doppler ultrasound, computed tomography, magnetic resonance imaging, and histology. This association further supports the hypothesis that focal nodular hyperplasia is a response to a preexisting vascular abnormality. PMID:1551514

Lalonde, L; Van Beers, B; Trigaux, J P; Delos, M; Melange, M; Pringot, J

1992-01-01

465

Focal nodular hyperplasia in association with spontaneous intrahepatic portosystemic venous shunt  

Microsoft Academic Search

We report a case of focal nodular hyperplasia in an adolescent with a spontaneous intrahepatic portosystemic venous shunt. Diagnosis was established by duplex and color Doppler ultrasound, computed tomography, magnetic resonance imaging, and histology. This association further supports the hypothesis that focal nodular hyperplasia is a response to a preexisting vascular abnormality.

Lucie Lalonde; Bernard Van Beers; Jean-Paul Trigaux; Monique Delos; Michel Melange; Jacques Pringot

1992-01-01

466

A Multi-Mode Blade Damping Control using Shunted Piezoelectric Transducers with Active Feedback Structure  

NASA Technical Reports Server (NTRS)

The Structural Dynamics and. Mechanics branch (RXS) is developing smart adaptive structures to improve fan blade damping at resonances using piezoelectric (PE) transducers. In this presentation, only one shunted PE transducer was used to demonstrate active control of multi-mode blade resonance damping on a titanium alloy (Ti-6A1-4V) flat plate model, regardless of bending, torsion, and 2-stripe modes. This work would have a significant impact on the conventional passive shunt damping world because the standard feedback control design tools can now be used to design and implement electric shunt for vibration control. In other words, the passive shunt circuit components using massive inductors and. resistors for multi-mode resonance control can be replaced with digital codes. Furthermore, this active approach with multi patches can simultaneously control several modes in the engine operating range. Dr. Benjamin Choi presented the analytical and experimental results from this work at the Propulsion-Safety and. Affordable Readiness (P-SAR) Conference in March, 2009.

Choi, Benjamin; Morrison, Carlos; Min, James

2009-01-01

467

Speed and voltage regulation of d.c. shunt machines using power transistor in field circuit  

Microsoft Academic Search

A simple method for speed and voltage regulation of d.c. shunt machines is presented. The method is based on the use of a power transistor circuit which automatically adjusts the field current Such that the Speed or output voltage, as the case may be, is maintained constant with increasing load on the machine. An added advantage of this inothod is

VIMAL SINGH; S. K. KAK

1974-01-01

468

Analysis of postural sway in patients with normal pressure hydrocephalus: effects of shunt implantation  

PubMed Central

Poor postural balance is one of the major risk factors for falling in normal pressure hydrocephalus (NPH). Postural instability in the clinic is commonly assessed based upon force platform posturography. In this study we focused on the identification of changes in sway characteristics while standing quiet in patients with NPH before and after shunt implantation. Postural sway area and sway radius were analyzed in a group of 9 patients and 46 controls of both genders. Subject's spontaneous sway was recorded while standing quiet on a force platform for 30-60 s, with eyes open and then closed. Both analyzed sway descriptors identified between-group differences and also an effect of shunt implantation in the NPH group. Sway radius and sway area in patients exhibited very high values compared with those in the control group. Importantly, the effect of eyesight in patients was not observed before shunt implantation and reappeared after the surgical treatment. The study documents that static force platform posturography may be a reliable measure of postural control improvement due to shunt surgery. PMID:20156726

2009-01-01

469

Analysis of postural sway in patients with normal pressure hydrocephalus: effects of shunt implantation.  

PubMed

Poor postural balance is one of the major risk factors for falling in normal pressure hydrocephalus (NPH). Postural instability in the clinic is commonly assessed based upon force platform posturography. In this study we focused on the identification of changes in sway characteristics while standing quiet in patients with NPH before and after shunt implantation. Postural sway area and sway radius were analyzed in a group of 9 patients and 46 controls of both genders. Subject's spontaneous sway was recorded while standing quiet on a force platform for 30-60 s, with eyes open and then closed. Both analyzed sway descriptors identified between-group differences and also an effect of shunt implantation in the NPH group. Sway radius and sway area in patients exhibited very high values compared with those in the control group. Importantly, the effect of eyesight in patients was not observed before shunt implantation and reappeared after the surgical treatment. The study documents that static force platform posturography may be a reliable measure of postural control improvement due to shunt surgery. PMID:20156726

Czerwosz, L; Szczepek, E; Blaszczyk, J W; Sokolowska, B; Dmitruk, K; Dudzinski, K; Jurkiewicz, J; Czernicki, Z

2009-12-01

470

Piezoelectric Shunt Vibration Damping of F-15 Panel under High Acoustic Excitation  

NASA Technical Reports Server (NTRS)

At last year's SPIE symposium, we reported results of an experiment on structural vibration damping of an F-15 underbelly panel using piezoelectric shunting with five bonded PZT transducers. The panel vibration was induced with an acoustic speaker at an overall sound pressure level (OASPL) of about 90 dB. Amplitude reductions of 13.45 and 10.72 dB were achieved for the first and second modes, respectively, using single- and multiple-mode shunting. It is the purpose of this investigation to extend the passive piezoelectric shunt-damping technique to control structural vibration induced at higher acoustic excitation levels, and to examine the controllability and survivability of the bonded PZT transducers at these high levels. The shunting experiment was performed with the Thermal Acoustic Fatigue Apparatus (TAFA) at the NASA Langley Research Center using the same F-15 underbelly panel. The TAFA is a progressive wave tube facility. The panel was mounted in one wall of the TAFA test section using a specially designed mounting fixture such that the panel was subjected to grazing-incidence acoustic excitation. Five PZT transducers were used with two shunt circuits designed to control the first and second modes of the structure between 200 and 400 Hz. We first determined the values of the shunt inductance and resistance at an OASPL of 130 dB. These values were maintained while we gradually increased the OASPL from 130 to 154 dB in 6-dB steps. During each increment, the frequency response function between accelerometers on the panel and the acoustic excitation measured by microphones, before and after shunting, were recorded. Good response reduction was observed up to the 148dB level. The experiment was stopped at 154 dB due to wire breakage from vibration at a transducer wire joint. The PZT transducers, however, were still bonded well on the panel and survived at this high dB level. We also observed shifting of the frequency peaks toward lower frequency when the OASPL was increased. Detailed experimental results will be presented.

Wu, Shu-Yau; Turner, Travis L.; Rizzi, Stephen A.

2000-01-01

471

The Influence of Crying on the Ductus Arteriosus Shunt and Left Ventricular Output at Birth.  

PubMed

Background: During neonatal transition, ductus arteriosus (DA) flow changes from right-to-left to left-to-right and contributes considerably to the increase in pulmonary blood flow. Large transpulmonary pressures generated by crying at birth can influence the DA shunt. Objective: This study aimed to assess differences in DA shunt during quiet breathing and crying directly after birth. Methods: In healthy term infants born by caesarean section, echocardiography was performed at 2, 5 and 10 min after birth. The velocity time integral of DA flow, DA flow ratio (right-to-left/left-to-right flow) and left ventricular output were assessed using echocardiography. Shunting was compared within each patient during crying and quiet breathing, and between time points. Results: A total of 23 infants were studied. The velocity time integral of left-to-right shunting was significantly larger during the inspiratory phase of crying than during quiet breathing [12.8 (9.2-17.4) vs. 5.9 (3.9-7.7) cm at 2 min, p < 0.0001; 14.3 (11.5-22.3) vs. 6.7 (4.1-11.1) cm at 5 min, p < 0.0001, and 18.6 (14.8-22.5) vs. 6.7 (4.4-10.7) cm at 10 min, p < 0.0001, after birth]. The increase in left-to-right shunting during crying was independent from the cardiac cycle as the QRS start of shunt interval time was 138 (82) ms during crying and 156 (35) ms during quiet breathing (n.s.). The DA flow ratio was lower in infants who cried at 0-1 time points versus those who cried at 2-3 time points (n.s.) out of the 3 time points measured. Left ventricular output was higher in infants who cried at 2-3 time points versus 0-1 time points (n.s.). Conclusion: Crying at birth significantly influences the DA shunt during transition. © 2014 S. Karger AG, Basel. PMID:25471487

van Vonderen, Jeroen J; Roest, Arno A W; Walther, Frans J; Blom, Nico A; van Lith, Jan M M; Hooper, Stuart B; Te Pas, Arjan B

2014-12-01

472

Blood volume and body fluid compartments in lambs with aortopulmonary left-to-right shunts.  

PubMed Central

A left-to-right shunt is accompanied by an increased plasma and blood volume. Since this is likely realized through renin/aldosterone-mediated salt and water retention, other body fluid compartments may be changed too. Therefore, we studied blood volume and body fluid compartments by a single-injection, triple-indicator dilution technique in nine 8-wk-old lambs with an aortopulmonary left-to-right shunt (55 +/- 3% of left ventricular output; mean +/- SEM) and in 11 control lambs, 2.5 wk after surgery. Systemic blood flow was maintained at the same level as in control lambs, but the aortic pressure of the shunt lambs was lower. Blood volume in shunt lambs was larger than in control lambs (110 +/- 6 vs. 84 +/- 7 ml/kg, P < 0.001) through an increase in plasma volume, which correlated significantly with the magnitude of the left-to-right shunt (r = 0.81, P < 0.01). Red blood cell volume was equal to that of control lambs. Evidence was obtained that the increase in plasma volume was induced by a transient increase in renin (8.0 +/- 2.2 vs. 1.6 +/- 0.2 nmol.l-1.h-1; P < 0.02) and aldosterone (0.51 +/- 0.14 vs. 0.24 +/- 0.09 nmol/liter) concentrations. Interstitial water volume, however, was not significantly different from that in control lambs. The amount of intravascular protein was significantly higher than in control lambs (5.0 +/- 0.3 vs. 3.5 +/- 0.2 g/kg body mass, P < 0.001). There were no significant differences in intracellular and total body water volumes between the two groups. We conclude that the increased amount of intravascular protein confines the fluid retained by the kidneys to the vascular compartment. PMID:1430202

Gratama, J W; Dalinghaus, M; Meuzelaar, J J; Gerding, A M; Koers, J H; Zijlstra, W G; Kuipers, J R

1992-01-01

473

Reduced clearance of proteins labeled with diisopropylfluorophosphate in portacaval-shunted rats.  

PubMed

Portacaval shunting is a model for hepatic encephalopathy that causes chronic hyperammonemia, disruption of metabolic, signaling, and neurotransmitter systems, and progressive morphological changes. Exposure of cultured cells to ammonia raises intralysosomal pH and inhibits proteolysis, and the present study tested the hypothesis that proteolytic capacity is diminished in portacaval-shunted rats. Proteins were labeled in vivo with tracer doses of diisopropylfluorophosphate (DFP) and clearance of label was assayed. This approach labeled proteins independent of protein synthesis, which is reported to be altered in shunted rats, and avoided complications arising from re-utilization of labeled amino acids that causes underestimation of degradation rate. Characterization of DFP labeling showed that protein labeling was fast, about 50% of the label was released during a 24 h interval, labeling by DFP metabolites was negligible, inhibition of brain acetylcholinesterase was not detectable, and labeling by [(3)H]- and [(14)C]DFP was equivalent. To assay degradative capacity, proteins were first labeled with [(3)H]DFP, followed by labeling with [(14)C]DFP that was given 24 or 72 h later. The (3)H/(14)C ratio in each animal was used as a relative measure of removal of (3)H-labeled proteins. (3)H/(14)C ratios were generally significantly higher in portacaval-shunted rats than in controls, consistent with reduced proteolytic capacity. Assays of amino acid incorporation into brain protein generally replicated literature reports, supporting the conclusion that protein synthesis unlikely to be markedly inhibited and amino acid recycling influences calculated protein synthesis rates in shunted rats. Therapeutic strategies to reduce ammonia level would help normalize lysosomal functions and protein and lipid turnover. PMID:24154686

Dienel, Gerald A; Cruz, Nancy F

2014-12-01

474

The antimicrobial lysine-peptoid hybrid LP5 inhibits DNA replication and induces the SOS response in Staphylococcus aureus  

PubMed Central

Background The increase in antibiotic resistant bacteria has led to renewed interest in development of alternative antimicrobial compounds such as antimicrobial peptides (AMPs), either naturally-occurring or synthetically-derived. Knowledge of the mode of action (MOA) of synthetic compounds mimicking the function of AMPs is highly valuable both when developing new types of antimicrobials and when predicting resistance development. Despite many functional studies of AMPs, only a few of the synthetic peptides have been studied in detail. Results We investigated the MOA of the lysine-peptoid hybrid, LP5, which previously has been shown to display antimicrobial activity against Staphylococcus aureus. At concentrations of LP5 above the minimal inhibitory concentration (MIC), the peptoid caused ATP leakage from bacterial cells. However, at concentrations close to the MIC, LP5 inhibited the growth of S. aureus without ATP leakage. Instead, LP5 bound DNA and inhibited macromolecular synthesis. The binding to DNA also led to inhibition of DNA gyrase and topoisomerase IV and caused induction of the SOS response. Conclusions Our data demonstrate that LP5 may have a dual mode of action against S. aureus. At MIC concentrations, LP5 binds DNA and inhibits macromolecular synthesis and growth, whereas at concentrations above the MIC, LP5 targets the bacterial membrane leading to disruption of the membrane. These results add new information about the MOA of a new synthetic AMP and aid in the future design of synthetic peptides with increased therapeutic potential. PMID:23945181

2013-01-01

475

Vascular plug-assisted retrograde transvenous obliteration of portosystemic shunts for refractory hepatic encephalopathy: a case report.  

PubMed

While balloon-assisted retrograde transvenous obliteration (BRTO) has been used for two decades in Asia for the management of gastric variceal bleeding, it is still an emerging therapy elsewhere. Given the shunt closure brought about by the procedure, BRTO has also been used for the management of portosystemic encephalopathy with promising results. Modified versions of BRTO have been developed, including plug-assisted retrograde transvenous obliteration (PARTO), where a vascular plug is deployed within a portosystemic shunt. To our knowledge, we present the first North American case of PARTO in the setting of a large splenorenal shunt for the management of portosystemic encephalopathy. PMID:24744943

Park, Jonathan K; Cho, Sung-Ki; Kee, Stephen; Lee, Edward W

2014-01-01