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Tip
Kinds of Tip Terms modified by Tip Selected AbstractsTour Into the Picture using a Vanishing Line and its Extension to Panoramic ImagesCOMPUTER GRAPHICS FORUM, Issue 3 2001Hyung Woo Kang Tour into the picture (TIP) proposed by Horry et al.13 is a method for generating a sequence of walk-through images from a single reference picture (or image). By navigating a 3D scene model constructed from the picture, TIP produces convincing 3D effects. Assuming that the picture has one vanishing point, they proposed the scene modeling scheme called spidery mesh. However, this scheme has to go through major modification when the picture contains multiple vanishing points or does not have any well-defined vanishing point. Moreover, the spidery mesh is hard to generalize for other types of images such as panoramic images. In this paper, we propose a new scheme for TIP which is based on a single vanishing line instead of a vanishing point. Based on projective geometry, our scheme is simple and yet general enough to address the problems faced with the previous method. We also show that our scheme can be naturally extended to a panoramic image. [source] Rarely Decorated Rutile Frameworks Built from Triangular Organic Spacers and Distorted Octahedral Co3 Building BlocksEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 24 2007Feng Luo Abstract Under mild temperatures, the self-assembly of CoCl2 and H3BTC in a solution of dmso generates a guest-free metal,organic polymer, namely Co3(BTC)2(,1 -dmso)2(,2 -dmso)2(1: dmso = dimethylsulfoxide, H3BTC = 1,3,5-benzenetricarboxylic acid). In 1, the CoII ions show the six-coordinate octahedral geometry completed by the BTC3, ions and the dmso oxygen atoms; remarkably, the coordinated dmso ligands not only act as terminal ligands to complete the octahedral geometry of the CoII ions, but also play an important role in bridging CoII ions together to give the Co3 secondary building units (SBUs). From a topological viewpoint, this novel polymer is classified to be the decorated (3,6)-connected rutile net with the (4.62)2(42.610.83) topology, where BTC3, ligands and Co3 SBUs are viewed to be the 3- and 6-connected nodes, respectively. In addition, the magnetic properties of 1 are explored by using a linear trinuclear cobalt mode, thusleading to g = 2.41, J = ,34.92 cm,1, TIP = 340,×,10,6 cm3,mol,1,, = ,6 K (a , parameter was included to take into account intertrinuclear interactions).(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source] Achieving a natural glanular meatus for distal hypospadias with a narrow and shallow plate: Tubularized incised plate versus modified Barcat repairINTERNATIONAL JOURNAL OF UROLOGY, Issue 7 2008Yutaro Hayashi Objectives: Although the tubularized incised plate (TIP) repair has become the most popular surgical procedure for distal hypospadias, some authors suggest that this is not suitable for hypospadias with a narrow plate or shallow groove. Methods: The configuration and position of the reconstructed meatus were postoperatively analyzed in patients with distal hypospadias whose preoperative urethral plates were shallow or narrow. The findings were compared between six patients undergoing TIP repair and seven patients undergoing modified Barcat (BAVIS) repair. Results: Among those undergoing the TIP procedure, a slit-like meatus at the tip of the glans was achieved in one patient, a slit-like meatus at the mid portion of the glans in four patients and a round meatus at the mid portion of the glans in one patient. In those repaired by the BAVIS procedure, a slit-like meatus at the tip of glans was achieved in three patients, a round or irregularly shaped meatus at the tip of the glans in two patients, an irregularly shaped meatus at the mid portion of the glans in one patient and neourethral dehiscence in one patient. Conclusions: The present study confirms that a higher rate of achieving slit-like meatus but a lower rate of locating in the glans tip can be attained after TIP repair. On the other hand, there is a higher rate of locating the meatus in the glans tip but a lower rate of achieving a slit-like meatus after BAVIS repair. [source] Incorporation of TIP (paclitaxel, ifosfamide, cisplatin) into first-line therapy for intermediate to poor risk testicular germ cell tumors with unfavorable marker decline after initial two cycles chemotherapy: A report of three casesINTERNATIONAL JOURNAL OF UROLOGY, Issue 5 2007Jun-Ichiro Ishioka Abstract: Three patients of advanced-non-seminomatous germ cell tumors (International Germ Cell Cancer Collaborative Group classification: poor risk, 2; intermediate, 1) without evidence of a second primary germ cell tumor were treated. The patients received two cycles of standard BEP (bleomycin, etopside, cisplatin) or VIP/VB (etoposide, ifosphamide, cisplatin/vinblastine, bleomycin) therapy first. All patients in this trial showed unfavorable marker response to these therapies and received four cycles of TIP subsequently. A complete remission was observed in all patients. No patient experienced life-threatening toxicity. During the 34-month observation period, all patients were alive without progression. [source] Low-Temperature Synthesis of Fully Crystallized Spherical BaTiO3 Particles by the Gel,Sol MethodJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 12 2004Un-Yeon Hwang The synthesis of spherical BaTiO3 particles was attempted by a new technique, the "gel,sol method," at 45°C. The (Ba,Ti) gel used as a starting material was prepared by aging mixtures of titanyl acylate with a barium acetate aqueous solution ([glacial acetic acid (AcOH)]/[titanium isopropoxide (TIP)] = 4, [barium acetate]/[TIP] = 1) at 45°C for 48 h. Potassium hydroxide (KOH) was used as a catalyst for the formation of BaTiO3. Powder X-ray diffractometry (XRD) results and Fourier-transform infrared (FT-IR) measurements for the (Ba,Ti) gel showed that the gel was amorphous, but the spatial arrangement of barium and titanium in the (Ba,Ti) gel is similar to that in crystalline BaTiO3 particles. Fully crystallized spherical BaTiO3 powder with a particle size of 40,250 nm formed at the very low reaction temperature of 45°C. Scanning electron microscopy images showed that the final particles formed via aggregation of the fine particles that seem to be the primary particles of bulk (Ba,Ti) gel. From the XRD, FT-IR, and Raman spectroscopy analysis, it was found that the crystal structure of the as-prepared particles continuously transformed from cubic to tetragonal as the calcination temperature increased, and high crystalline tetragonal BaTiO3 phase was obtained at 1000°C after 1 h of heat treatment. [source] Novel tobramycin inhalation powder in cystic fibrosis subjects: Pharmacokinetics and safetyPEDIATRIC PULMONOLOGY, Issue 4 2007David E. Geller MD Abstract Aerosolized antibiotics are associated with a high treatment burden that can result in non-adherence to chronic therapy. We evaluated the pharmacokinetics (PK) and safety of tobramycin inhalation powder (TIP), a novel dry-powder formulation designed to deliver a high payload of tobramycin topically to the lungs for management of chronic Pseudomonas aeruginosa infections. This was a multi-center, open-label, sequential-cohort, single-dose, dose-escalation study using the standard 300 mg dose of tobramycin solution for inhalation (TSI) as an active control. Subjects were randomized to TIP or TSI in a 3:1 ratio in each of five cohorts. Measurements included serum and sputum tobramycin concentrations, administration time, serum chemistries, acute change in lung function, and adverse events (AEs). Out of 90 randomized subjects, 86 had data for safety analysis; and 84 had data for PK analysis. Serum tobramycin PK profiles were similar for TIP and TSI. Four capsules of 28 mg TIP (total tobramycin dose 112 mg) produced comparable systemic exposure to 300 mg TSI, in less than one-third the administration time. The most common AEs associated with TIP were cough (20%) and dysgeusia (17%). TIP allows for faster and more efficient pulmonary delivery of tobramycin than TSI and has a safety profile that supports continued clinical investigation. The increased rate of local respiratory tract irritation noted with TIP is not unexpected with a high-payload powder formulation. The development of dry powder inhaled antibiotics may represent an important advance in the treatment of chronic lung infections. Pediatr Pulmonol. 2007; 42:307,313. © 2007 Wiley-Liss, Inc. [source] Preparation of nano-sized UV-absorbing titanium-oxo-clusters via a photo-curing ceramer process,POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 2-3 2005Mark D. Soucek Abstract A titanium sol-gel precursor, titanium (IV) isopropoxide (TIP), was mixed with an epoxidized linseed oil (ELO). Using a cationic super-acid photoinitiator, triarylsulfonium hexafluoroantimonate, both the organic phase (ELO) and the inorganic phase (TIP) were concomitantly cured. The exposure to moisture was strictly controlled before and during the UV-curing process. The UV-Visible spectra, SAXs (small angle X-ray), DMA (dynamic mechanical properties), and contact angle were investigated as a function of sol-gel precursor. The UV-Visible spectra revealed that the inorganic/organic hybrid materials were more effective at blocking the UV-light than nanoparticulate titanium dioxide while maintaining complete transparency in the visible region. The contact angle data indicated that the inorganic phase preferentially was concentrated at the film-surface interface. The SAXs data was indicative of a 2--5 nm titanium-oxo-cluster size, and the DMA data suggests a well distributed system. Copyright © 2005 John Wiley & Sons, Ltd. [source] Loss of TIP1;1 aquaporin in Arabidopsis leads to cell and plant deathTHE PLANT JOURNAL, Issue 6 2004Shisong Ma Summary Arabidopsis TIP1;1 (,TIP) is a member of the tonoplast family of aquaporins (AQP). Using RNA interference (RNAi) we reduced TIP1;1 to different extent in various lines. When most severely affected, miniature plants died, a phenotype partially complemented by the TIP1;1 homolog McMIP-F. Less severely affected lines produced small plants, early senescence, and showed lesion formation. The relative water content in TIP1;1 RNAi plants was not significantly affected. Global expression profiling suggested a disturbance in carbon metabolism in RNAi lines with upregulated transcripts for functions in carbon acquisition and respiration, vesicle transport, signaling and transcription, and radical oxygen stress. Metabolite profiles showed low glucose, fructose, inositol, and threonic, succinic, fumaric, and malic acids, but sucrose levels were similar to WT. Increased amounts were found for raffinose and several unknown compounds. TIP1;1 RNAi plants also contained high starch and apoplastic carbohydrate increased. A GFP-TIP1;1 fusion protein indicated tonoplast location in spongy mesophyll cells, and high signal intensity in palisade mesophyll associated with vesicles near plastids. Signals in vascular tissues were strongest not only in vesicle-like structures but also outlined large vacuoles. Compromised routing of carbohydrate and lack of sucrose provision for cell-autonomous functions seems to characterize this RNAi phenotype. We suggest a function for TIP1;1 in vesicle-based metabolite routing through or between pre-vacuolar compartments and the central vacuole. Phenotype and expression characteristics support a view of TIP1;1 functioning as a marker for vesicles that are targeted to the central vacuole. [source] Response of the Asian summer monsoon to changes in El Niño propertiesTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 607 2005H. Annamalai Abstract Diagnostics from observed precipitation and National Centers for Environmental Prediction,National Center for Atmospheric Research re-analysis products reveal that after the 1976,77 climate shift in the Pacific there was a dramatic change in the response of the Indian summer monsoon (ISM) to El Niño, particularly during the months of July and August. Based on 1950,75 (PRE76) and 1977,2001 (POST76) El Niño composites: the western North Pacific monsoon (WNPM) was stronger than normal in both periods; the ISM was weaker than normal during the entire monsoon season in PRE76, but in POST76 was weaker only during the onset and withdrawal phases. In terms of observed sea surface temperature (SST) during July,August, the major differences between the two periods are the presence of cold SST anomalies over the Indo,Pacific warm pool and the intensity of warm SST anomalies in the central Pacific in POST76. The effect of these differences on the ISM is investigated in a suite of experiments with an Atmospheric General Circulation Model (AGCM) that has a realistic monsoon precipitation climatology. Separate ten-member ensemble simulations with the AGCM were conducted for PRE76 and POST76 El Niño events with SST anomalies inserted as follows: (i) tropical Indo,Pacific (TIP), (ii) tropical Pacific only (TPO), and (iii) tropical Indian Ocean only (TIO). Qualitatively, TPO solutions reproduce the observed differences in the monsoon response in both periods. Specifically, during July,August of POST76 the cold SST anomalies in conjunction with remote subsidence suppress precipitation (3,5 mm day,1) over the maritime continent and equatorial central Indian Ocean. Inclusion of Indian Ocean SST anomalies in the TIP runs further suppresses precipitation over the entire equatorial Indian Ocean. The low-level anticyclonic circulation anomalies that develop as a Rossby-wave response to these convective anomalies increase the south-westerlies over the northern Indian Ocean, and favour a stronger ISM and WNPM. During PRE76 the non-occurrence of cold SST anomalies over the Indo,Pacific warm pool reinforces El Niño's suppression on the ISM. In contrast, TIO solutions show a reduced ISM during July,August of POST76; the solutions, however, show a significant effect on the WNPM during both PRE76 and POST76 periods. It is argued that SSTs over the entire tropical Indo,Pacific region need to be considered to understand the El Niño Southern Oscillation,monsoon linkage, and to make predictions of rainfall over India and the western North Pacific. Copyright © 2005 Royal Meteorological Society [source] Tubularized incised-plate urethroplasty for proximal hypospadiasBJU INTERNATIONAL, Issue 1 2002W.T. Snodgrass Objective To report the experience of one surgeon using tubularized incised-plate (TIP) urethroplasty to repair proximal hypospadias in a consecutive series of boys. Patients and methods The records of 33 consecutive patients with midshaft to scrotal hypospadias undergoing TIP repair by one surgeon were reviewed. Dorsal plication was used as necessary for penile straightening, to preserve the urethral plate. Standard TIP urethroplasty was undertaken, and the follow-up included the selective use of neourethral calibration and urethroscopy. Results Plication was necessary in 18 (55%) patients. The incised plate had a supple appearance in all but two boys. The mean (range) follow-up was 9 (1,48) months and included calibration in 16 (48%) and urethroscopy in 13 (39%) patients. Complications were noted in 11 (33%) boys, of whom seven (21%) developed small fistulae. The two patients in whom the incised plate appeared unhealthy had dehiscence of the repair and contracture of the neourethra with recurrent penile curvature, respectively. There was one meatal stenosis and one short neourethral stricture. Conclusions TIP urethroplasty can be used to repair proximal hypospadias in the absence of severe penile curvature, and if the incised urethral plate has a supple appearance. As with distal hypospadias repair, the procedure creates a normal-appearing penis with a slit-like meatus. [source] Polymer Scaffolds for Small-Diameter Vascular Tissue EngineeringADVANCED FUNCTIONAL MATERIALS, Issue 17 2010Haiyun Ma Abstract To better engineer small-diameter blood vessels, a few types of novel scaffolds are fabricated from biodegradable poly(L -lactic acid) (PLLA) by means of thermally induced phase-separation (TIPS) techniques. By utilizing the differences in thermal conductivities of the mold materials and using benzene as the solvent scaffolds with oriented gradient microtubular structures in the axial or radial direction can be created. The porosity, tubular size, and the orientational direction of the microtubules can be controlled by the polymer concentration, the TIPS temperature, and by utilizing materials of different thermal conductivities. These gradient microtubular structures facilitate cell seeding and mass transfer for cell growth and function. Nanofibrous scaffolds with an oriented and interconnected microtubular pore network are also developed by a one-step TIPS method using a benzene/tetrahydrofuran mixture as the solvent without the need for porogen materials. The structural features of such scaffolds can be conveniently adjusted by varying the solvent ratio, phase-separation temperature, and polymer concentration to mimic the nanofibrous features of an extracellular matrix. These scaffolds were fabricated for the tissue engineering of small-diameter blood vessels by utilizing their advantageous structural features to facilitate blood-vessel regeneration. [source] Aiming at minimal invasiveness as a therapeutic strategy for Budd-Chiari syndrome,HEPATOLOGY, Issue 5 2006Aurélie Plessier The 1-year spontaneous mortality rate in patients with Budd-Chiari syndrome (BCS) approaches 70%. No prospective assessment of indications and impact on survival of current therapeutic procedures has been performed. We evaluated a therapeutic strategy uniformly applied during the last 8 years in a single referral center. Fifty-one consecutive patients first received anticoagulation and were treated for associated diseases. Symptomatic patients were considered for hepatic vein recanalization; then for transjugular intrahepatic portosystemic shunt (TIPS), and finally for liver transplantation. The absence of a complete response led to the next procedure. Assessment was according to the strategy, whether procedures were technically applicable and successful. At entry, median (range) Child-Pugh score and Clichy prognostic index were 8 (5,12), and 5.4 (3.1,7.7), respectively. A complete response was achieved on medical therapy alone in 9 patients; after recanalization in 6, TIPS in 20, liver transplantation in 9, and retransplantation in 1. Of the 41 patients considered for recanalization, the procedure was not feasible in 27 and technically unsuccessful in 3. Of the 34 patients considered for TIPS, the procedure was considered not feasible in 9 and technically unsuccessful in 4. At 1 year of follow-up, a complete response to TIPS was achieved in 84%. One- and 5-year survival from starting anticoagulation were 96% (95% CI, 90,100) and 89% (95% CI, 79,100), respectively. In conclusion, excellent survival can be achieved in BCS patients when therapeutic procedures are introduced by order of increasing invasiveness, based on the response to previous therapy rather than on the severity of the patient's condition. (HEPATOLOGY 2006;44:1308,1316.) [source] The effect of single oral low-dose losartan on posture-related sodium handling in post-TIPS ascites-free cirrhosis,HEPATOLOGY, Issue 3 2006George Therapondos Post-TIPS ascites-free patients with cirrhosis and previous refractory ascites demonstrate subtle sodium retention when challenged with a high sodium load. This is also observed in pre-ascitic patients with cirrhosis. This phenomenon is dependent on an intrarenal angiotensin II (ANG II) mechanism related to the assumption of erect posture. We investigated whether similar mechanisms were involved in post-TIPS ascites-free patients, by studying 10 patients with functioning TIPS and no ascites. We measured the effect of changing from supine to erect posture on sodium excretion at baseline and after single oral low dose losartan (7.5 mg) which has been shown to blunt proximal and distal tubular sodium reabsorption in pre-ascites. At baseline, the assumption of erect posture produced a reduction in sodium excretion (from 0.30 ± 0.06 to 0.13 ± 0.02 mmol/min, P = .05), which was mainly due to an increase in proximal tubular reabsorption of sodium (PTRNa) (69.7 ± 3.1% to 81.1 ± 1.8%, P = .003). The administration of losartan resulted in a blunting of PTRNa (supine 69.7 ± 3.1% to 63.9 ± 3.9%, P = .01 and erect 81.1 ± 1.8% to 73.8 ± 2.4%, P = .01), accompanied by an increased distal tubular reabsorption of sodium in both postures, with no overall improvement in sodium excretion on standing. In conclusion, post-TIPS ascites-free patients with cirrhosis exhibit erect posture-induced sodium retention. We speculate that (1) this effect is partly mediated by the effect of ANG II on PTRNa and (2) that the inability of low dose losartan to block the erect posture-induced sodium retention may be related to the erect posture-induced rise in aldosterone which is unmodified by losartan. (HEPATOLOGY 2006;44:640,649.) [source] Humoral and cardiac effects of TIPS in cirrhotic patients with different "effective" blood volumeHEPATOLOGY, Issue 6 2003Francesco Salerno M.D. The aim of this study was to evaluate the cardiac effects of transjugular intrahepatic portosystemic shunts (TIPS) in cirrhotic patients with different effective blood volume. Two-dimensional echocardiography was performed before and 7 and 28 days after TIPS insertion in 7 cirrhotic patients with PRA <4 ng/mL/h (group A, normal effective blood volume) and 15 with PRA >4 ng/mL/h (group B, reduced effective blood volume). Before TIPS, most cirrhotic patients showed diastolic dysfunction as indicated by reduced early maximal ventricular filling velocity (E)/late filling velocity (A) ratio. Patients of group B differed from patients of group A because of smaller left ventricular volumes and stroke volume, indicating central underfilling. After TIPS insertion, portal decompression was associated with a significant increase of cardiac output (CO) and a decrease of peripheral resistances. The most important changes were recorded in patients of group B, who showed a significant increase of both the end-diastolic left ventricular volumes and the E/A ratio and a significant decrease of PRA. In conclusion, these results show that the hemodynamic effects of TIPS differ according to the pre-TIPS effective blood volume. Furthermore, TIPS improves the diastolic cardiac function of cirrhotic patients with effective hypovolemia. This result is likely due to a TIPS-related improvement of the fullness of central blood volume. [source] Is TIPS a cost-effective therapy for the prevention of variceal rebleeding?HEPATOLOGY, Issue 1 2002Adnan Said M.D. No abstract is available for this article. [source] Hepatic arterial buffer response in patients with advanced cirrhosisHEPATOLOGY, Issue 3 2002Veit Gülberg Hepatic arterial buffer response (HABR) is considered an important compensatory mechanism to maintain perfusion of the liver by hepatic arterial vasodilation on reduction of portal venous perfusion. HABR has been suggested to be impaired in patients with advanced cirrhosis. In patients with hepatopetal portal flow, placement of a transjugular intrahepatic portosystemic shunt (TIPS) reduces portal venous liver perfusion. Accordingly, patients with severe cirrhosis should have impaired HABR after TIPS implantation. Therefore, the aim of this study was to investigate the effect of TIPS on HABR as reflected by changes in resistance index (RI) of the hepatic artery. A total of 366 patients with cirrhosis (Child-Pugh class A, 106; class B, 168; class C, 92) underwent duplex Doppler ultrasonographic examination with determination of RI and maximal flow velocity in the portal vein before and 1 month after TIPS placement. Portosystemic pressure gradient was determined before and after TIPS placement. In 29 patients with hepatofugal portal blood flow, RI was significantly lower than in 337 patients with hepatopetal flow (0.63 ± 0.02 vs. 0.69 ± 0.01; P < .001). TIPS induced a significant decrease of the RI in patients with hepatopetal flow (RI, 0.69 ± 0.01 before vs. 0.64 ± 0.01 after TIPS; P = .001) but not in patients with hepatofugal flow (RI, 0.63 ± 0.02 before vs. 0.63 ± 0.02 after TIPS; NS). This response was not dependent on the Child-Pugh class. In conclusion, our results suggest that some degree of HABR is preserved even in patients with advanced cirrhosis with significant portal hypertension. [source] TIPS versus drug therapy in preventing variceal rebleeding in advanced cirrhosis: A randomized controlled trialHEPATOLOGY, Issue 2 2002Àngels Escorsell Prevention of variceal rebleeding is mandatory in cirrhotic patients. We compared the efficacy, safety, and cost of transjugular intrahepatic portosystemic shunt (TIPS) versus pharmacologic therapy in preventing variceal rebleeding in patients with advanced cirrhosis. A total of 91 Child-Pugh class B/C cirrhotic patients surviving their first episode of variceal bleeding were randomized to receive TIPS (n = 47) or drug therapy (propranolol + isosorbide-5-mononitrate) (n = 44) to prevent variceal rebleeding. Mean follow-up was 15 months. Rebleeding occurred in 6 (13%) TIPS-treated patients versus 17 (39%) drug-treated patients (P = .007). The 2-year rebleeding probability was 13% versus 49% (P = .01). A similar number of reinterventions were required in the 2 groups; these were mainly angioplasty ± restenting in the TIPS group (90 of 98) and endoscopic therapy for rebleeding in the medical group (45 of 62) (not significant). Encephalopathy was more frequent in TIPS than in drug-treated patients (38% vs. 14%, P = .007). Child-Pugh class improved more frequently in drug-treated than in TIPS-treated patients (72% vs. 45%; P = .04). The 2-year survival probability was identical (72%). The identified cost of therapy was double for TIPS-treated patients. In summary, medical therapy was less effective than TIPS in preventing rebleeding. However, it caused less encephalopathy, identical survival, and more frequent improvement in Child-Pugh class with lower costs than TIPS in high-risk cirrhotic patients. This suggests that TIPS should not be used as a first-line treatment, but as a rescue for failures of medical/endoscopic treatments (first-option therapies). [source] TIPS is a useful long-term derivative therapy for patients with Budd-Chiari syndrome uncontrolled by medical therapyHEPATOLOGY, Issue 1 2002Antonia Perelló Patients with Budd-Chiari syndrome (BCS) may require treatment with portal decompressive surgery or liver transplantation. Transjugular intrahepatic portosystemic shunt (TIPS) represents a new treatment alternative, but its long-term effect on BCS outcome has not been evaluated. Twenty-one patients with BCS consecutively admitted to our unit were evaluated. The mean follow-up was 4 ± 3 years. Seven patients had nonprogressive forms and were successfully controlled with medical therapy; 1 case, with a short-length hepatic vein stenosis was successfully treated by angioplasty. All 8 patients are alive and asymptomatic. The remaining 13 patients, had a TIPS because of clinical deterioration (in one of them, because early TIPS thrombosis a successful side-to-side portacaval shunt [SSPCS] was performed) followed by an improvement in clinical condition. However, a patient with fulminant liver failure before TIPS insertion, died 4 months later and another patient with cirrhosis at diagnosis had liver transplantation 2 years later. The remaining 11 patients are alive and free of ascites. In 3 of these patients TIPS is patent after 3, 6, and 12 months. The remaining 8 patients developed late TIPS dysfunction. In two of these cases, after angioplasty and restenting, TIPS is patent after a follow-up of 9 and 80 months. In 5 other patients, recurring TIPS occlusion was not further corrected because no signs of portal hypertension were present. In conclusion, in patients with BCS uncontrolled with medical therapy, TIPS is a highly effective technique that is associated with long-term survival. [source] Comparison of the Relative Reactivities of the Triisopropylsilyl Group With Two Fluorous AnalogsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2009Amador Garcia Sancho Abstract The relative stabilities of two fluorous analogs, diisopropyl(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10- heptadecafluorodecyl)silyl and diisopropyl- (4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoroundecyl)silyl [C8F17(CH2)nSi(i- Pr)2, where n=2 or 3], of the standard triisopropylsilyl (TIPS) group are compared in the setting of alcohol protection. The fluorous silyl groups can be installed under standard conditions in comparable yields to the TIPS group, but the derived fluorous silyl ethers are more labile than TIPS ethers towards cleavage by both acids and fluoride. [source] Effect of the preparation conditions on the permeation of ultrahigh-molecular-weight polyethylene/silicon dioxide hybrid membranesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2010Nana Li Abstract Porous ultrahigh-molecular-weight polyethylene/SiO2 membranes were prepared by thermally induced phase separation (TIPS) with white mineral oil as the diluent and SiO2 as an additive. Influential factors, including extraction method, SiO2 content, and cooling rate, were investigated. The results suggest that the both porosity and pure water flux of the membranes by extraction of the solvent naphtha in the tension state with alcohol were the best among our research. With increasing SiO2 content, the porosity, pure water flux, and pore diameter increased. However, with excessive SiO2 content, defects formed easily. Moreover, SiO2 improved the pressure resistance of the membranes. The cooling rate directly effected the crystal structure. A slow cooling rate was good for crystal growth and the integration of the diluent. Therefore, the porosity, pure water flux, and bubble-point pore diameter increased with decreasing cooling rate. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] A new technique for foaming submicron size poly(methyl methacrylate) particlesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2007Hiroyuki Ogawa Abstract About 0.7,2 ,m diameter poly (methyl methacrylate) (PMMA) foamed particles were prepared via thermally induced phase separation (TIPS) from a PMMA/ethanol mixture and vacuum dried. It was found that ethanol, known to be a poor solvent to PMMA, could dissolve PMMA when the temperature was over 60°C. The solubility of PMMA (Mw = 15,000 and Mw = 120,000) in ethanol was measured and was found to increase as the temperature increased. PMMA particles on the scale of submicron and single micron diameter could be precipitated from the PMMA/ethanol solution by temperature quenching. Then, since the precipitated particles contained a certain amount of ethanol, the precipitated particles could be foamed using the ethanol as a foaming agent in a vacuum drying process. Vacuum drying at temperatures slightly below the glass transition temperature of the polymer could make the particles foam. The effects of foaming temperature and the molecular weight of the polymer on the size of foamed particles were investigated. The experimental results showed that the vapor pressure and the molecular weight of the polymer are key factors determining the expandability of the micro particles. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 [source] Comparison study of Doppler ultrasound surveillance of expanded polytetrafluoroethylene-covered stent versus bare stent in transjugular intrahepatic portosystemic shuntJOURNAL OF CLINICAL ULTRASOUND, Issue 7 2010Qian Huang MD Abstract Objective. This prospectively randomized controlled study aimed to assess with Doppler ultrasound (US) the shunt function of expanded polytetrafluoroethylene (ePTFE)-covered transjugular intrahepatic portosystemic shunt (TIPS) stent versus bare stent and to evaluate the usefulness of routine TIPS follow-up of ePTFE-covered stents. Methods. Sixty consecutive patients were randomized for bare or covered transjugular TIPS stenting in our institution between April 2007 and April 2009. Data of follow-up Doppler US, angiography, and portosystemic pressure gradient measurements were collected and analyzed. Results. The follow-up period was 8.34 ± 4.42 months in the bare-stent group and 6.16 ± 3.89 months in the covered-stent group. Baseline clinical characteristics were similar in both groups. Two hundred three US studies were performed in 60 patients, with a mean of 3.4 per patient, and demonstrated abnormalities in 28 patients (21 bare stents, 7 ePTFE-covered stents), 19 of them (13 in bare-stent group, 6 in covered-stent group) showing no clinical evidence of recurrence. Ten of 13 patients in the bare-stent group underwent balloon angioplasty or additional stent placement, whereas only one of six patients in the covered-stent group needed reintervention for intimal hyperplasia. The average peak velocity in the midshunt of ePTFE-covered stent was 139 ± 26 cm/s after TIPS creation and 125 ± 20 cm/s during follow-up, which was significantly higher than the bare-stent group (p < 0.05). The main portal vein and hepatic artery showed higher flow velocities in the ePTFE-covered stent group than in the bare-stent group. ePTFE-covered stents maintained lower portosystemic pressure gradient than bare stents (9.5 ± 2.9 versus 13.2 ± 1.5 mmHg, p < 0.05). Conclusions. ePTFE-covered stents resulted in higher patency rates and better hemodynamics than bare stents. Routine US surveillance may not be necessary in patients with ePTFE-covered TIPS stent. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound 38:353-360, 2010 [source] Portosystemic pressure gradient during transjugular intrahepatic portosystemic shunt with Viatorr stent graft: What is the critical low threshold to avoid medically uncontrolled low pressure gradient related complications?JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 1 2008Hwan-Hoon Chung Abstract Background:, Inappropriately decreased portosystemic pressure gradient (PSG) during transjugular intrahepatic portosystemic shunt (TIPS) can cause fatal complications but the critical low threshold of PSG is still not clear. The aim of the present study was to evaluate the critical low threshold of PSG during TIPS. Methods:, Sixty-six patients with cirrhosis who successfully underwent de novo TIPS with Viatorr stent grafts were studied. Medically uncontrolled low pressure gradient (LPR) complication was defined as when a patient died, or when acute transplantation or a TIPS reduction procedure was performed due to refractory encephalopathy or the deterioration of hepatic function within 3 months after the procedure. For the determination of the risk group for medically uncontrolled LPR complications, the Child-Pugh score and the model of end-stage liver disease (MELD) score showing a 100% negative predictive value was decided on as a threshold for each score. The risk group was defined when either of both scores was higher than its threshold. For the determination of a critical low post-TIPS PSG, a value of post-TIPS PSG showing the highest discrimination power on the receiver operating characteristic (ROC) curve in the risk group was decided on as a critical low threshold of PSG. The medically uncontrolled LPR complication rates of the patients with the determined threshold or lower were evaluated for the risk group. Results:, Medically uncontrolled LPR complications developed in nine patients (13.6%). Five patients died and four patients had TIPS reduction procedures. Patients with more than 10 on the Child-Pugh score or more than 14 on the MELD score were determined to be the risk group and 34 patients were included. The critical lower threshold of the post-TIPS PSG showing the highest discrimination power on the ROC curve was 5 mmHg (sensitivity 100%, specificity 72%), and the medically uncontrolled LPR complication rates of the patients with 5 mmHg or lower on the post-TIPS PSG were 56.3% (9/16) in the risk group. Conclusions:, The critical threshold of the post-TIPS PSG to avoid the medically uncontrolled LPR complications of TIPS was >5 mmHg. The PSG should not be reduced below this level in the risk group. [source] Management of refractory ascites and hepatorenal syndromeJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 4 2002Anuchit Chutaputti Abstract, Refractory ascites and hepatorenal syndrome (HRS) are the late complications of the terminal stages of cirrhosis. The definitions of refractory ascites and HRS proposed by the International Ascites Club in 1996 are now widely accepted, and are useful in diagnosis, treatment and research in this field. In both conditions, the only treatment of proven value for improved survival is liver transplantation. However, because of better understanding about the pathophysiology of HRS, including the roles of portal hypertension, ascites formation and hemodynamic derangements, treatments such as transjugular intrahepatic portasystemic shunt (TIPS) and new pharmacological agents may be considered to alleviate the problem prior to transplantation. Symptomatic treatment of refractory ascites includes TIPS and repeated large volume paracentesis. Transjugular intrahepatic portasystemic shunt can improve survival while waiting for liver transplantation. Practical management guidelines for TIPS and large volume paracentesis, including the prevention and management of further complications, are considered in this review. © 2002 Blackwell Publishing Asia Pty Ltd [source] Transjugular intrahepatic cavoportal shunt for Budd,Chiari syndromeJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2005T Ul Haq Summary Budd,Chiari syndrome (BCS) is characterized by obstruction of the hepatic venous outflow tract. Therapeutic options for BCS are limited. We report a case of a 21-year-old woman with protein S and C deficiency with gross ascites. Treatment with transjugular intrahepatic portosystemic shunt (TIPS) was attempted, which revealed occluded hepatic veins, so transcaval TIPS was performed. No serious procedure-related complication occurred. After successful shunt creation, the patient's symptoms subsided and she was discharged and followed up for 6 months. [source] Reversible Cytotoxic Edema in a Cirrhotic Patient Following TIPSJOURNAL OF NEUROIMAGING, Issue 4 2009James R. Babington MD ABSTRACT The authors report the magnetic resonance imaging (MRI) findings in a 52-year-old man with cirrhosis from chronic hepatitis C who developed episodic acute hepatic encephalopathy Type C following placement of transjugular intrahepatic portosystemic shunt (TIPS). Brain MRI revealed hyperintense T2 signal and restricted diffusion distributed through the cerebral cortex. The patient's mentation improved with treatment of his hyperammonemia. Brain MRI performed 5 months later revealed diffuse cerebral atrophy and new areas of hyperintense T2 signal in the cerebral white matter. The cortical signal abnormalities and low apparent diffusion coefficient values on the initial MRI resolved with exception of a mild amount of hyperintense FLAIR signal in the cingulate cortex. Acute hepatic encephalopathy following portosystemic shunting,either from placement of TIPS or from development of spontaneous shunts,is a widely recognized complication of portal hypertension and cirrhosis. We report MRI findings of reversible cytotoxic edema in a patient with acute hepatic encephalopathy following placement of TIPS. [source] Predictors of the recurrence of hepatic encephalopathy in lactulose-treated patientsALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 9 2010J. S. BAJAJ Aliment Pharmacol Ther,31, 1012,1017 Summary Background, Lactulose is considered first-line therapy for hepatic encephalopathy. However, the effect of adherence with lactulose on recurrence of hepatic encephalopathy outside clinical trials remains unclear. Aim, To determine the association of lactulose use with recurrence of hepatic encephalopathy episodes. Methods, Patients with cirrhosis who were initiated on lactulose after an index hepatic encephalopathy episode in a liver-transplant centre were retrospectively reviewed. Recurrence of hepatic encephalopathy, precipitating factors and adherence on lactulose were investigated using chart review and electronic pharmacy records. Patients with/without hepatic encephalopathy recurrence were compared, and predictors of recurrence were analysed. Results, A total of 137 patients with cirrhosis (age 55 ± 6years, MELD 17 ± 7) who were initiated on lactulose after the index hepatic encephalopathy episode were included. Of these, 103 patients developed recurrent hepatic encephalopathy 9 ± 1 months after their index episode; 39 (38%) of these were not adherent on lactulose, 56 (54%) were adherent and 8 (8%) had lactulose-associated dehydration leading to recurrence. Recurrent hepatic encephalopathy precipitants in lactulose-adherent patients were sepsis (19%), GI bleeding (15%), hyponatremia (4%) and TIPS (7%). Overall, all patients who did not suffer recurrence were adherent on lactulose. In contrast, the adherence rate for those who recurred was only 64% (P = 0.00001). On multivariate regression, lactulose non-adherence (OR 3.26) and MELD score (OR 1.14) were the factors that predicted recurrence. Conclusion, Lactulose non-adherence and lactulose-associated dehydration were associated with nearly half of recurrent hepatic encephalopathy episodes. [source] Outcomes of transjugular intrahepatic portosystemic shunt through the left branch vs. the right branch of the portal vein in advanced cirrhosis: a randomized trialLIVER INTERNATIONAL, Issue 7 2009Lei Chen Abstract Background/Aims: The transjugular intrahepatic portosystemic shunt (TIPS) is technically divided into TIPS through the left branch of the portal vein (TIPS-LBPV) and TIPS through the right branch of the portal vein (TIPS-RBPV). In order to compare their advantages and disadvantages, this randomized, controlled trial was designed to investigate their outcomes in advanced cirrhotic patients. Methods: Seventy-two patients were randomly placed into TIPS-LBPV (36 patients) and TIPS-RBPV (36 patients, with four failures) groups, and they were prospectively followed for 2 years after TIPS implantation. Results: Patients who underwent the two different kinds of TIPS were balanced during recruitment for this study. The incidences of overall encephalopathy and de novo encephalopathy in the TIPS-LBPV group were significantly lower than that of the TIPS-RBPV group during follow-up (P=0.036 and 0.012 respectively). The incidences of rebleeding or re-intervention and improvement of ascites were similar between groups (P>0.05). Patients undergoing TIPS-RBPV required more rehospitalization and incurred more costs than those who underwent TIPS-LBPV (P=0.030 and 0.039 respectively). There was no significant difference between the two groups in survival based on a survival curve constructed according to the Kaplan,Meier method (P>0.05). Conclusion: Patients undergoing TIPS-LBPV had a lower incidence of encephalopathy, less rehospitalization and lower costs after TIPS implantation compared with patients undergoing TIPS-RBPV. [source] The natural history of parallel transjugular intrahepatic portosystemic stent shunts using uncovered stent: the role of host-related factorsLIVER INTERNATIONAL, Issue 5 2006Ahmed Helmy Abstract: Objectives: Parallel shunts (PS) are used in the management of transjugular intrahepatic portosystemic stent-shunt (TIPS) insufficiency, a major limitation of the technique. This study describes the natural history of PS, and uses them as a model to assess the role of host factors in the development of primary shunt insufficiency. Methods: Out of 338 patients with TIPS, 40 (11.8%) patients required insertion of a PS. Baseline and follow-up data of these patients were collected. Regular shunt surveillance involved biannual clinic visits and transjugular portography. Results: The non-PS group (group 1; n=298) and the PS group (group 2; n=40) had similar baseline demographic and disease characteristics. Index shunts of both groups and the PS produced a significant portal pressure gradient drop (P<0.001), which was less in the index shunts of Group 2 (P<0.02 for both). PS had similar cumulative shunt patency rates to those of the index shunts of Group 1, and both were greater than those of index shunts in Group 2 (P<0.001 for both). The intervention rate (number of interventions/number of check portograms × 100) was similar for PS and the index shunts of Group 1 (38.7% and 43% respectively), but was significantly higher in the index shunts of Group 2 (85.6%; P<0.01 for both). In Group 1 and Group 2, 144 patients (48.3%) and 21 patients (52.5%) died during follow-up after a median period of 23.4 and 8.9 months respectively. Conclusions: These findings do not support the hypothesis that shunt insufficiency is related to host factors. [source] Hepatic hydrothorax , pathophysiology, diagnosis and treatment , review of the literatureLIVER INTERNATIONAL, Issue 4 2004Chamutal Gur Abstract: Hepatic hydrothorax is defined as the accumulation of significant pleural effusion in a cirrhotic patient without primary pulmonary or cardiac disease. Hydrothorax is uncommon occurring in up to 4,6% of all patients with cirrhosis and up to 10% in patients with decompensated cirrhosis. Although ascites is usually present, hydrothorax can occur in the absence of ascites. Patients with hepatic hydrothorax usually have advanced liver disease with portal hypertension and most of them will require liver transplantation. Over the last few years, new insights into the pathogenesis of this entity have lead to improved treatment modalities such as portosystemic shunts (TIPS) and video-assisted thoracoscopy for closure of diaphragmatic defects. These modalities may be of help as a bridge to transplantation. The aim of this review is to describe recent developments in the pathogenesis, diagnosis and treatment of hepatic hydrothorax. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||