WorldWideScience

Sample records for biodegradable urethral stent

  1. [Biodegradable catheters and urinary stents. When?

    Science.gov (United States)

    Soria, F; Morcillo, E; López de Alda, A; Pastor, T; Sánchez-Margallo, F M

    2016-10-01

    One of the main wishes in the field of urinary catheters and stents is to arm them with biodegradable characteristics because we consider a failure of these devices the need for retrieval, the forgotten catheter syndrome as well as the adverse effects permanent devices cause after fulfilling their aim. The efforts focused in new designs, coatings and biomaterials aim to increase the biocompatibility of theses internal devices. Lately, there have been correct advances to answer the main challenges regarding biodegradable ureteral devices. Thus, modulation of the rate of degradation has been achieved thanks to new biomaterials and the use of copolymers that enable to choose the time of permanence as it is programmed with conventional double J catheters. Biocompatibility has improved with the use of new polymers that adapt better to the urine. Finally, one of the main problems is elimination of degraded fragments and experimentally it has be demonstrated that new designs elicit controlled degradation, from distal to proximal; using stranding and combination of copolymers degradation may be caused by dilution, reducing fragmentation to the last stages of life of the prosthesis. Moreover, it has been demonstrated that biodegradable catheters potentially may cause less urinary tract infection, less encrustation and predictably they will diminish catheter morbidity, since their degradation process reduces adverse effects. Regarding the development of biodegradable urethral stents, it is necessary to find biomaterials that enable maintaining their biomechanical properties in the long term, keeping open the urethral lumen both in patients with BPH and urethral stenosis. Modulation of the time of degradation of the prosthesis has been achieved, but the appearance of urothelial hyperplasia is still a constant in the initial phases after implantation. The development of drug eluting stents, anti-proliferative or anti-inflammatory, as well as biodegradable stents biocoated is a

  2. Endoscopic removal of a proximal urethral stent using a holmium laser: Case report and literature review

    Directory of Open Access Journals (Sweden)

    Francisco Botelho

    2012-01-01

    Full Text Available Urethral stents were initially developed for the management of urethral strictures and obstructive voiding disorders in select patients. Urethral stent complications are common and may require stent explantation, which is often quite challenging. We present our experience with endoscopic removal of an encrusted UroLume proximal urethral stent in a 72-year-old male using a holmium laser. The literature on various management options and outcomes for urethral stent removal is reviewed. Endoscopic removal of proximal urethral stents is feasible and safe and should be considered as the primary treatment option in patients requiring stent extraction.

  3. Removal of retrievable self-expandable urethral stents: experience in 58 stents

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ji Hoon; Song, Ho-Young; Kim, Jin Hyoung; Ko, Heung-Kyu; Kim, Yong Jae; Woo, Chul-Woong; Kim, Tae-Hyung; Ko, Gi-Young; Yoon, Hyun-Ki; Sung, Kyu-Bo [Asan Medical Center, Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Seoul (Korea); Park, Hyungkeun [Asan Medical Center, Department of Urology, University of Ulsan College of Medicine, Seoul (Korea)

    2006-09-15

    The purpose of this study was to retrospectively evaluate the safety and efficacy of removing retrievable self-expandable urethral stents using a retrieval hook wire. Under fluoroscopic guidance, the removal of 58 polyurethane or PTFE (polytetrafluoroethylene)-covered stents was attempted in 33 patients using a retrieval hook wire. Indications for removal were elective removal (n=21), stent migration (n=19), formation of tissue hyperplasia around or inside of the stent (n=14), stent deformity (n=3), and severe pain (n=1). The mean time the stents remained in place was 64.8{+-}42.9 days (range, 1-177 days). Fifty-six (97%) of the 58 stents were successfully removed using the retrieval hook wire despite the following difficulties; hook wire disconnection (n=2), untied drawstrings (n=3), and polyurethane membrane disruption/separation (n=4). The removal procedure using a retrieval hook wire failed in two stents (3%) which had migrated into the urinary bladder. One of the two stents with migration into the urinary bladder was removed using a snare through the cystostomy route. The overall complication rate was 14% (seven hematuria cases and one urethral tear case), and all were minor and spontaneously resolved without further treatment. In conclusion, removal of retrievable urethral stents using a retrieval hook wire was safe and effective despite some technical difficulties. It is a useful method for allowing temporary stent placement and solving various complications of stent use. (orig.)

  4. Impacted calculus within a urethral stent: A rare cause of urinary retention

    Directory of Open Access Journals (Sweden)

    Shanmugasundaram Rajaian

    2011-01-01

    Full Text Available An elderly male presented to the emergency department with acute urinary retention. He had poor flow of urine associated with serosanguinous discharge per urethra for 3 days duration. Earlier he underwent permanent metallic urethral stenting for post TURP bulbar urethral stricture. Plain X-ray of Pelvis showed an impacted calculus within the urethral stent in bulbar urethra. Urethrolitholapaxy was done with semirigid ureteroscope. Urethral stent was patent and well covered. Subsequently he had an uneventful recovery. We describe a unique case of acute urinary retention due to calculus impaction within a urethral stent.

  5. SIU/ICUD Consultation on Urethral Strictures: Dilation, internal urethrotomy, and stenting of male anterior urethral strictures.

    Science.gov (United States)

    Buckley, Jill C; Heyns, Chris; Gilling, Peter; Carney, Jeff

    2014-03-01

    Male urethral stricture is one of the oldest known urologic diseases, and continues to be a common and challenging urologic condition. Our objective was to review all contemporary and historial articles on the topic of dilation, internal urethrotomy, and stenting of male anterior urethral strictures. An extensive review of the scientific literature concerning anterior urethral urethrotomy/dilation/stenting was performed. Articles were included that met the criteria set by the International Consultation on Urological Diseases (ICUD) urethral strictures committee and were classified by level of evidence using the Oxford Centre for Evidence-Based Medicine criteria adapted from the work of the Agency for Health Care Policy and Research as modified for use in previous ICUD projects. Using criteria set forth by the ICUD, a committee of international experts in urethral stricture disease reviewed the literature and created a consensus statement incorporating levels of evidence and expert opinion in regard to dilation, internal urethrotomy, and stenting of male anterior urethral strictures.

  6. Transurethral resection of fibrotic scar tissue combined with temporary urethral stent placement for patients with in anterior urethral stricture

    Directory of Open Access Journals (Sweden)

    Cheol Yong Yoon

    2014-08-01

    Full Text Available Introduction Fibrotic scar formation is a main cause of recurrent urethral stricture after initial management with direct vision internal urethrotomy (DVIU. In the present study, we devised a new technique of combined the transurethral resection of fibrotic scar tissue and temporary urethral stenting, using a thermo-expandable urethral stent (MemokathTM 044TW in patients with anterior urethral stricture. Materials and Methods As a first step, multiple incisions were made around stricture site with cold-cutting knife and Collins knife electrode to release a stricture band. Fibrotic tissue was then resected with a 13Fr pediatric resectoscope before deployment of a MemokathTM 044TW stent (40 – 60mm on a pre-mounted sheath using 0° cystoscopy. Stents were removed within 12 months after initial placement. Results We performed this technique on 11 consecutive patients with initial (n = 4 and recurrent (n = 7 anterior urethral stricture (April 2009 – February 2013. At 18.9 months of mean follow-up (12-34 months, mean Qmax (7.8±3.9ml/sec vs 16.8 ± 4.8ml/sec, p < 0.001, IPSS (20.7 vs 12.5, p = 0.001 , and QoL score (4.7 vs 2.2, p < 0.001 were significantly improved. There were no significant procedure-related complications except two cases of tissue ingrowth at the edge of stent, which were amenable by transurethral resection. In 7 patients, an average 1.4 times (1-5 times of palliative urethral dilatation was carried out and no patients underwent open surgical urethroplasty during the follow-up period. Conclusion Combined transurethral resection and temporary urethral stenting is a effective therapeutic option for anterior urethral stricture. Further investigations to determine the long-term effects, and safety profile of this new technique are warranted.

  7. Polymeric Biodegradable Stent Insertion in the Esophagus

    Directory of Open Access Journals (Sweden)

    Kai Yang

    2016-04-01

    Full Text Available Esophageal stent insertion has been used as a well-accepted and effective alternative to manage and improve the quality of life for patients diagnosed with esophageal diseases and disorders. Current stents are either permanent or temporary and are fabricated from either metal or plastic. The partially covered self-expanding metal stent (SEMS has a firm anchoring effect and prevent stent migration, however, the hyperplastic tissue reaction cause stent restenosis and make it difficult to remove. A fully covered SEMS and self-expanding plastic stent (SEPS reduced reactive hyperplasia but has a high migration rate. The main advantage that polymeric biodegradable stents (BDSs have over metal or plastic stents is that removal is not require and reduce the need for repeated stent insertion. But the slightly lower radial force of BDS may be its main shortcoming and a post-implant problem. Thus, strengthening support of BDS is a content of the research in the future. BDSs are often temporarily effective in esophageal stricture to relieve dysphagia. In the future, it can be expect that biodegradable drug-eluting stents (DES will be available to treat benign esophageal stricture, perforations or leaks with additional use as palliative modalities for treating malignant esophageal stricture, as the bridge to surgery or to maintain luminal patency during neoadjuvant chemoradiation.

  8. Biomechanical Challenges to Polymeric Biodegradable Stents.

    Science.gov (United States)

    Soares, Joao S; Moore, James E

    2016-02-01

    Biodegradable implants have demonstrated clinical success in simple applications (e.g., absorbable sutures) and have shown great potential in many other areas of interventional medicine, such as localized drug delivery, engineered tissue scaffolding, and structural implants. For endovascular stenting and musculoskeletal applications, they can serve as temporary mechanical support that provides a smooth stress-transfer from the degradable implant to the healing tissue. However, for more complex device geometries, in vivo environments, and evolving load-bearing functions, such as required for vascular stents, there are considerable challenges associated with the use of biodegradable materials. A biodegradable stent must restore blood flow and provide support for a predictable appropriate period to facilitate artery healing, and subsequently, fail safely and be absorbed in a controllable manner. Biodegradable polymers are typically weaker than metals currently employed to construct stents, so it is difficult to ensure sufficient strength to keep the artery open and alleviate symptoms acutely while keeping other design parameters within clinically acceptable ranges. These design challenges are serious, given the general lack of understanding of biodegradable polymer behavior and evolution in intimal operating conditions. The modus operandi is mainly empirical and relies heavily on trial-and-error methodologies burdened by difficult, resource-expensive, and time-consuming experiments. We are striving for theoretical advancements systematizing the empirical knowledge into rational frameworks that could be cast into in silico tools for simulation and product development optimization. These challenges are evident when one considers that there are no biodegradable stents on the US market despite more than 30 years of development efforts (and currently only a couple with CE mark). This review summarizes previous efforts at implementing biodegradable stents, discusses the

  9. Overnight urethral stenting after tubularized incised plate urethroplasty for distal hypospadias.

    Science.gov (United States)

    Ritch, Chad R; Murphy, Alana M; Woldu, Solomon L; Reiley, Elizabeth A; Hensle, Terry W

    2010-06-01

    The duration of urethral stenting after tubularized incised plate (TIP) urethroplasty for hypospadias varies among surgeons. Typically the catheter is left for up to 7 days with the goal of minimizing post-operative complications. We describe our experience with overnight stenting for distal TIP hypospadias repair. A retrospective chart review was performed on patients who underwent TIP hypospadias repair from 2003 to 2008. Patients who had their urethral catheter overnight were included in this analysis. Outcomes analyzed were the rates of: urethrocutaneous fistula, meatal stenosis, urethral stricture and urinary tract infections. A total of 64 patients underwent outpatient TIP hypospadias repair. Forty-nine patients had overnight urethral stenting with at least 12 months follow-up and were included in the analysis. Five of the 49 patients (10.2%) developed urethrocutaneous fistula. Of these five patients, two had undergone re-do hypospadias repair. The fistula rate in primary repairs was 3/45 (6.7%). There were no incidences of meatal stenosis, urinary tract infections or urethral strictures. In our experience, overnight urethral stenting for TIP hypospadias repair does not significantly affect the rates of urethrocutaneous fistula, meatal stenosis and urinary tract infections. Patients who have had a primary TIP hypospadias repair may have their urethral catheter removed safely on post-operative day one.

  10. Fully biodegradable coronary stents : progress to date.

    Science.gov (United States)

    Ramcharitar, Steve; Serruys, Patrick W

    2008-01-01

    The limitations of currently available metallic drug-eluting stents have renewed interest in biodegradable stents (BDS). Apart from removing the (offending) foreign material that may potentiate a thrombotic event, BDS have the advantage of avoiding 'full metal jackets,' and thus can preclude subsequent coronary surgery. In addition, they do not interfere with the diagnostic evaluation of non-invasive imaging such as cardiac magnetic resonance and CT. There are now several BDS in development or in clinical trials that incorporate a variety of biodegradable polymer technologies. Two broad categories of materials are generally used: those made from organic biopolymers and those made from corrodible metals. However, to date, none of the materials/stents tested have been able to establish a perfect balance between biocompatibility, the kinetics of degradation needed to maintain mechanical strength to limit recoil, and inflammation. However, studies, such as the ABSORB trial with the everolimus eluting poly-L-lactide stent, which demonstrated comparable restenotic rates with bare metallic stents and a low incidence of major adverse cardiac events (MACE) at 12 months of 3.3%, with only one patient having a non-Q-wave myocardial infarction and no target lesion revascularization, suggest that there has been significant progress with respect to the earlier prototypes. The acute recoil observed could potentially be addressed with the polytyrosine REVA stent currently being evaluated in the RESORB trial, which incorporates a novel locking mechanism within its design. Alternative BDS designs include the combination of an antiproliferative drug with endothelial progenitor cell capturing antibodies to facilitate epithelialization and/or dual eluting having, in addition to the antiproliferative drug, polymeric salicyclic acid to limit inflammation. Compared with biodegradable polymers, there are fewer metals used in the manufacture of BDS. The only metal BDS in trials is the

  11. Immersed multilayer biodegradable ureteral stent with reformed biodegradation: An in vitro experiment.

    Science.gov (United States)

    Yang, Ganggang; Xie, Hua; Huang, Yichen; Lv, Yiqing; Zhang, Mingqing; Shang, Yafeng; Zhou, Junmei; Wang, Liping; Wang, Jin-Ye; Chen, Fang

    2017-03-01

    Objective The aim of this study was to develop a novel immersed multilayer biodegradable ureteral stent with reformed biodegradation and evaluate it in vitro. Methods Poly(glycolic-co-lactic acid) (PGLA), microsphere zein and BaSO4 were employed to produce a multilayer biodegradable stent using immersion technology. Tests of the biodegradable stents and conventional control stents were conducted in human urine in vitro to evaluate the biodegradable properties. The biocompatibility was assessed by the morphology and proliferation of urine-derived cells cultured with extracted media from the biodegradable stent and a latex material positive control. Results An immersed multilayer biodegradable stent was successfully produced. It began to degrade in week 2 and was fully degraded by week 4. The mass loss ratio in the first 2 weeks was low (approximately 10.0% at 1 week, 20.0% at 2 weeks) and increased after 3 weeks (approximately 70%) to the end of testing. During the first 2 weeks, the radial compression load performances of the biodegradable stents were better than those of the control stents with statistically significant differences ( p = 0.00, p = 0.01) and the tensile strengths were lower in the biodegradable stents than those in the control stents throughout the experiment. SEM showed that the stents degraded layer by layer from the outer to the inner wall. The influences on the cells of extracted medium from the biodegradable stents were morphologically slight and lower than 10% in relative growth rates. Conclusions This preliminary study demonstrates that the immersed multilayer biodegradable ureteral stent has good radial compression and biocompatible performance and can be degraded in vitro within 4 weeks in a moderate manner.

  12. Long-term result of Memokath urethral sphincter stent in spinal cord injury patients

    Directory of Open Access Journals (Sweden)

    Sett Pradipkumar

    2002-11-01

    Full Text Available Abstract Background Memokath urethral sphincter stents are used to facilitate bladder emptying in patients with spinal cord injury, but long term follow-up has not been reported. Methods Case series of ten men with spinal cord injury who underwent insertion of Memokath stents and were followed for up to nine years. Results Within four years, the stent had to be removed in nine out of ten patients because of: extensive mucosal proliferation causing obstruction to the lumen of the stent; stone around the proximal end of the stent, incomplete bladder emptying, and recurrent urinary infections; migration of the stent into the bladder related to digital evacuation of bowels; large residual urine; concretions within the stent causing obstruction to flow of urine, and partial blockage of the stent causing frequent episodes of autonomic dysreflexia. In one patient the stent continued to function satisfactorily after nine years. Conclusions The Memokath stent has a role as a temporary measure for treatment of detrusor-sphincter dyssynergia in selected SCI patients who do not get recurrent urinary infection and do not require manual evacuation of bowels.

  13. A review on biodegradable materials for cardiovascular stent application

    Science.gov (United States)

    Hou, Li-Da; Li, Zhen; Pan, Yu; Sabir, MuhammadIqbal; Zheng, Yu-Feng; Li, Li

    2016-09-01

    A stent is a medical device designed to serve as a temporary or permanent internal scaffold to maintain or increase the lumen of a body conduit. The researchers and engineers diverted to investigate biodegradable materials due to the limitation of metallic materials in stent application such as stent restenosis which requires prolonged anti platelet therapy, often result in smaller lumen after implantation and obstruct re-stenting treatments. Biomedical implants with temporary function for the vascular intervention are extensively studied in recent years. The rationale for biodegradable stent is to provide the support for the vessel in predicted period of time and then degrading into biocompatible constituent. The degradation of stent makes the re-stenting possible after several months and also ameliorates the vessel wall quality. The present article focuses on the biodegradable materials for the cardiovascular stent. The objective of this review is to describe the possible biodegradable materials for stent and their properties such as design criteria, degradation behavior, drawbacks and advantages with their recent clinical and preclinical trials.

  14. Biodegradable Metals for Cardiovascular Stent Application: Interests and New Opportunities

    Directory of Open Access Journals (Sweden)

    Maryam Moravej

    2011-06-01

    Full Text Available During the last decade, biodegradable metallic stents have been developed and investigated as alternatives for the currently-used permanent cardiovascular stents. Degradable metallic materials could potentially replace corrosion-resistant metals currently used for stent application as it has been shown that the role of stenting is temporary and limited to a period of 6–12 months after implantation during which arterial remodeling and healing occur. Although corrosion is generally considered as a failure in metallurgy, the corrodibility of certain metals can be an advantage for their application as degradable implants. The candidate materials for such application should have mechanical properties ideally close to those of 316L stainless steel which is the gold standard material for stent application in order to provide mechanical support to diseased arteries. Non-toxicity of the metal itself and its degradation products is another requirement as the material is absorbed by blood and cells. Based on the mentioned requirements, iron-based and magnesium-based alloys have been the investigated candidates for biodegradable stents. This article reviews the recent developments in the design and evaluation of metallic materials for biodegradable stents. It also introduces the new metallurgical processes which could be applied for the production of metallic biodegradable stents and their effect on the properties of the produced metals.

  15. A surface-modified biodegradable urethral scaffold seeded with urethral epithelial cells

    Institute of Scientific and Technical Information of China (English)

    FU Wei-jun; ZHANG Xu; WANG Zhong-xin; LI Gang; ZHANG Bing-hong; ZHANG Lei; HU Kun; HONG Bao-fa; WANG Xiao-xiong; CUI Fu-zhai

    2011-01-01

    Background Efficient cell adhesion and proliferation is a central issue in cell-based tissue engineering, which offers great promise for repair of urethral defects or strictures. This study evaluated the adhesion and growth of rabbit uroepithelium on a surface-modified three-dimensional poly-L-lactic acid (PLLA) scaffold.Methods Urethral mucosa were harvested from male New Zealand rabbits and the urothelium were dissociated and then cultured. Immunocytochemistry on cultured uroepithelium for pancytokeratin and uroplakin Ⅱ and TE-7 confirmed pure populations. After in vitro proliferation, cells were seeded onto a surface-modified urethral scaffold with non-knitted filaments. The morphology and viability of the cells were examined by immunohistochemical and fluorescence staining.Inverted and scanning microscopes were used to document cell growth and adhesion.Results Three to five days after primary culture, the uroepithelial cells gradually became confluent, assuming a cobblestone pattern. The filaments of the urethral scaffold had excellent biocompatibility and allowed growth of the uroepithelium, without affecting viability. The uroepithelial cells adhered to and grew well on the scaffold. After 3-7 days,the cells grew vigorously and meshes of the scaffold were full of uroepitheliums.Conclusions The surface-modified urethral scaffold with non-knitted filaments allows the growth of uroepithelium and can serve as a carrier for the tissue engineering of urethra.

  16. Urethritis

    Science.gov (United States)

    ... Sensitivity to the chemicals used in spermicides or contraceptive jellies, or foams Sometimes the cause is unknown. Risks for urethritis include: Being a female Being male, ages 20 to 35 Having many sexual partners ...

  17. Biolimus-eluting stents with biodegradable polymer versus bare-metal stents in acute myocardial infarction

    DEFF Research Database (Denmark)

    Räber, Lorenz; Kelbæk, Henning; Taniwaki, Masanori

    2014-01-01

    BACKGROUND: This study sought to determine whether the 1-year differences in major adverse cardiac event between a stent eluting biolimus from a biodegradable polymer and bare-metal stents (BMSs) in the COMFORTABLE trial (Comparison of Biolimus Eluted From an Erodible Stent Coating With Bare Meta...... to improve cardiovascular events compared with BMS beyond 1 year. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NTC00962416....

  18. Development of biodegradable magnesium alloy stents with coating

    Directory of Open Access Journals (Sweden)

    Lorenza Petrini

    2014-07-01

    Full Text Available Biodegradable stents are attracting the attention of many researchers in biomedical and materials research fields since they can absolve their specific function for the expected period of time and then gradually disappear. This feature allows avoiding the risk of long-term complications such as restenosis or mechanical instability of the device when the vessel grows in size in pediatric patients. Up to now biodegradable stents made of polymers or magnesium alloys have been proposed. However, both the solutions have limitations. The polymers have low mechanical properties, which lead to devices that cannot withstand the natural contraction of the blood vessel: the restenosis appears just after the implant, and can be ascribed to the compliance of the stent. The magnesium alloys have much higher mechanical properties, but they dissolve too fast in the human body. In this work we present some results of an ongoing study aiming to the development of biodegradable stents made of a magnesium alloy that is coated with a polymer having a high corrosion resistance. The mechanical action on the blood vessel is given by the magnesium stent for the desired period, being the stent protected against fast corrosion by the coating. The coating will dissolve in a longer term, thus delaying the exposition of the magnesium stent to the corrosive environment. We dealt with the problem exploiting the potentialities of a combined approach of experimental and computational methods (both standard and ad-hoc developed for designing magnesium alloy, coating and scaffold geometry from different points of views. Our study required the following steps: i selection of a Mg alloy suitable for stent production, having sufficient strength and elongation capability; ii computational optimization of the stent geometry to minimize stress and strain after stent deployment, improve scaffolding ability and corrosion resistance; iii development of a numerical model for studying stent

  19. A novel biodegradable esophageal stent: results from mechanical and animal experiments.

    Science.gov (United States)

    Liu, Jin; Shang, Liang; Liu, Jiyong; Qin, Chengyong

    2016-01-01

    Biodegradable esophageal stents eliminate stent retrieval, but usually induce hyperplasia. This study investigated the properties of a novel biodegradable stent in vitro and in vivo. The degradation of the novel stent was observed in phosphate buffered saline (PBS) for 8 weeks. The radial forces, pH values, morphology, and retention rate of the intrinsic viscosity (R[η]) of the new biodegradable stent were all evaluated. In vitro, the pH values remained constant for 4 weeks and declined from weeks 4 to 8. The biodegradable threads degraded and ruptured at 6 weeks. Consequently, the radial force of the stent decreased to zero at that time. The curve of R[η] decreased with time linearly in PBS. To study the stents in vivo, we used a stricture model in which the middle esophagus of rabbits was damaged by alkali burn. Stents were inserted 2 weeks after injury and observed for 8 weeks. We assessed complications related to stent insertion, degradation of the stent, and survival of the rabbits. Two stents migrated, and one rabbit died. In the other rabbits, two stents degraded and moved into the stomach during the sixth week, five during the seventh week and one during the eighth week, respectively. One stent remained in position until the end of the study. In conclusion, our newly designed stent retained the strong radial force of self-expandable metal stents (SEMSs) and maintained the biodegradable properties of biodegradable (BD) stents.

  20. Biolimus-eluting biodegradable polymer-coated stent versus durable polymer-coated sirolimus-eluting stent in unselected patients receiving percutaneous coronary intervention (SORT OUT V)

    DEFF Research Database (Denmark)

    Christiansen, Evald Høj; Jensen, Lisette Okkels; Thayssen, Per

    2013-01-01

    Third-generation biodegradable polymer drug-eluting stents might reduce the risk of stent thrombosis compared with first-generation permanent polymer drug-eluting stents. We aimed to further investigate the effects of a biodegradable polymer biolimus-eluting stent compared with a durable polymer...

  1. Dose perturbation due to the presence of a prostatic urethral stent in patients receiving pelvic radiotherapy: an in vitro study.

    Science.gov (United States)

    Gez, E; Cederbaum, M; Yachia, D; Bar-Deroma, R; Kuten, A

    1997-01-01

    Temporary metallic intraprostatic stent is a new alternative treatment for patients with urinary obstructive syndrome caused by prostate cancer. Definitive radiotherapy is a treatment of choice for localized prostate cancer. This study evaluates in vitro the effect of a urethral intraprostatic metallic stent on the dose absorbed by the surrounding tissue. The study was designed to mimic the conditions under which the prostatic stent is placed in the body during pelvic irradiation. A urethral stent composed of a 50% nickel-50% titanium alloy (Uracoil-InStent) was imbedded in material mimicking normal tissue (bolus) at a simulated body depth of 10 cm. The distribution of the absorbed dose of irradiation was determined by film dosimetry using Kodak X-Omat V film. Irradiation was done in a single field at the isocenter of a 6 MV linear accelerator with a field size of 7 x 7 cm. The degree of film blackening was in direct proportion to the absorbed dose. The measurements showed an increase in dose of up to 20% immediately before the stent and a decrease of up to 18% immediately after the stent. These changes occurred within a range of 1-3 mm from both sides of the stent. In practice, irradiation in prostate cancer is given by two pairs of opposed co-axial fields; a total of four fields (Box Technique). The dose perturbations are partly cancelled in a pair of opposed beams resulting in a net variation of +/- 4%; therefore, the presence of the intraprostatic stent should not influence radiotherapy planning for prostate cancer.

  2. Biodegradable stents for the treatment of bowel strictures in Crohn's disease

    DEFF Research Database (Denmark)

    Karstensen, John Gásdal; Christensen, Katrine Risager; Brynskov, Jørn

    2016-01-01

    BACKGROUND AND STUDY AIMS: In patients with Crohn's disease, the idea of biodegradable stents for treatment of bowel strictures with limited effect of endoscopic balloon dilation is tempting and initial results have been promising. The aim of this study was to evaluate the technical and clinical...... success of biodegradable stents for treatment of inflamed Crohn's strictures refractory to endoscopic balloon dilatation. PATIENTS AND METHODS: Consecutive patients treated with biodegradable stents due to Crohn's disease and inflamed bowel strictures refractory to endoscopic balloon dilatation were...... collapse (n = 1). CONCLUSIONS: In Crohn's disease, it is technically feasible to treat bowel strictures with biodegradable stents. However, we have stopped using biodegradable stents due to lack of clinical success and side effects such as mucosal overgrowth and stent collapse....

  3. Comparison of a biodegradable ureteral stent versus the traditional double-J stent for the treatment of ureteral injury: an experimental study.

    Science.gov (United States)

    Fu, Wei-Jun; Wang, Zhong-Xin; Li, Gang; Cui, Fu-Zhai; Zhang, Yuanyuan; Zhang, Xu

    2012-12-01

    Ureteral injury remains a major clinical problem; here we developed a biodegradable ureteral stent and compared its effectiveness with a double-J stent for treating ureteral injury. Eighteen dogs with injured ureters were subdivided into two groups. In group A, one injured ureter was treated with a biodegradable stent, whereas only end-to-end anastomosis was performed on the other side. In group B, one injured ureter was treated with a biodegradable stent, while a double-J stent was used on the other side. Intravenous urography, radioactive renography, histological examinations, scanning electron microscopy (SEM) and elemental composition analysis were performed at 40, 80 and 120 days postoperatively. Results showed that the biodegradable stent could effectively prevent hydronephrosis and hydroureter secondary to ureteral injury. Moreover all biodegradable stents gradually degraded and discharged completely in 120 days. SEM and elemental composition analysis of the surface of the double-J stent confirmed calcification at 80 days and calcific plaque at 120 days, while no signs of calcification were found in the biodegradable stent group. Histological studies found no difference between the biodegradable stented ureters and double-J stented ureters. It is concluded that the biodegradable ureteral stent was more advantageous than the double-J stent for treating ureteral injury in a canine model.

  4. Severe destruction of urethral lumen after wall stent implantation. Unusual radiological findings; Schwere Obliteration des Harnroehrenlumens nach Wall-Stent-Implantation. Eine ungewoehnliche radiologische Besonderheit

    Energy Technology Data Exchange (ETDEWEB)

    Ragozzino, A. [II Servizio di Radiologia, Azienda Autonoma di Rilievo Nazionale A. Cardarelli, Napoli (Italy); Testa, G. [XV Div. di Urologia, Azienda Autonoma di Rilievo Nazionale A. Cardarelli, Napoli (Italy); De Ritis, R. [II Servizio di Radiologia, Azienda Autonoma di Rilievo Nazionale A. Cardarelli, Napoli (Italy); Diettrich, A. [II Servizio di Radiologia, Azienda Autonoma di Rilievo Nazionale A. Cardarelli, Napoli (Italy); Tuccillo, M. [II Servizio di Radiologia, Azienda Autonoma di Rilievo Nazionale A. Cardarelli, Napoli (Italy)

    1997-07-01

    The treatment of urethral stricture is still a challenge for urologists. Irrespective of the treatment employed, urethral stricture recurs in about 30% of all cases. In recent years, the wall stent, originally conceived for vascular surgery, has proved to be effective for the treatment of bulbar urethral strictures. The results are good, morbidity and complications occur only occasionally. In this paper, we described the case of a young patient who suffered from complete occlusion of the prosthesis 8 months after its implantation. The low age of the patient and the X-ray features of this case are unusual. The obstruction was successfully resolved by endoscopic resection. Follow-up after 14 months revealed a mild, short stenosis of the proximal tip. (orig.) [Deutsch] Die Behandlung der Harnroehrenverengung wird auf ca. 30% aller Faelle geschaetzt, unabhaengig von den angewandten Behandlungsmethoden. In den letzten Jahren wurde die Wall-Stent-Prothese, die urspruenglich fuer die Gefaesschirurgie beabsichtigt war, erfolgreich in der Behandlung von bulbaeren Harnroehrenverengungen eingesetzt. Die Resultate waren befriedigend; Morbiditaet und Komplikationen waren nur gelegentlich zu verzeichnen. In dieser Arbeit wollen wir den Fall eines Patienten beschreiben, der an einer vollstaendigen Okklusion des Harnroehrenlumens litt, dessen Auftreten sich 8 Monate nach der Implantation der Prothese zeigte. Das junge Alter des Patienten und die roentgologische Besonderheit sind ungewoehnliche Elemente fuer diesen Fall. Die Obstruktion wurde erfolgreich mittels endoskopischer Resektion behandelt. Nach 14 Monaten zeigte die Follow-up-Untersuchung eine leichte, kurze Stenose der proximalen Prothesenspitze. (orig.)

  5. Fabrication of a Delaying Biodegradable Magnesium Alloy-Based Esophageal Stent via Coating Elastic Polymer

    Directory of Open Access Journals (Sweden)

    Tianwen Yuan

    2016-05-01

    Full Text Available Esophageal stent implantation can relieve esophageal stenosis and obstructions in benign esophageal strictures, and magnesium alloy stents are a good candidate because of biodegradation and biological safety. However, biodegradable esophageal stents show a poor corrosion resistance and a quick loss of mechanical support in vivo. In this study, we chose the elastic and biodegradable mixed polymer of Poly(ε-caprolactone (PCL and poly(trimethylene carbonate (PTMC as the coated membrane on magnesium alloy stents for fabricating a fully biodegradable esophageal stent, which showed an ability to delay the degradation time and maintain mechanical performance in the long term. After 48 repeated compressions, the mechanical testing demonstrated that the PCL-PTMC-coated magnesium stents possess good flexibility and elasticity, and could provide enough support against lesion compression when used in vivo. According to the in vitro degradation evaluation, the PCL-PTMC membrane coated on magnesium was a good material combination for biodegradable stents. During the in vivo evaluation, the proliferation of the smooth muscle cells showed no signs of cell toxicity. Histological examination revealed the inflammation scores at four weeks in the magnesium-(PCL-PTMC stent group were similar to those in the control group (p > 0.05. The α-smooth muscle actin layer in the media was thinner in the magnesium-(PCL-PTMC stent group than in the control group (p < 0.05. Both the epithelial and smooth muscle cell layers were significantly thinner in the magnesium-(PCL-PTMC stent group than in the control group. The stent insertion was feasible and provided reliable support for at least four weeks, without causing severe injury or collagen deposition. Thus, this stent provides a new stent for the treatment of benign esophageal stricture and a novel research path in the development of temporary stents in other cases of benign stricture.

  6. Finite element analyses for design evaluation of biodegradable magnesium alloy stents in arterial vessels

    Energy Technology Data Exchange (ETDEWEB)

    Wu Wei [Laboratory of Biological Structure Mechanics, Structural Engineering Department, Politecnico di Milano, Piazza Leonardo da Vinci, 32, 20133 Milan (Italy); Gastaldi, Dario, E-mail: dario.gastaldi@polimi.it [Laboratory of Biological Structure Mechanics, Structural Engineering Department, Politecnico di Milano, Piazza Leonardo da Vinci, 32, 20133 Milan (Italy); Yang Ke; Tan Lili [Division of Specialized Materials and Devices, Institute of Metal Research, Chinese Academy of Sciences, Shenyang (China); Petrini, Lorenza; Migliavacca, Francesco [Laboratory of Biological Structure Mechanics, Structural Engineering Department, Politecnico di Milano, Piazza Leonardo da Vinci, 32, 20133 Milan (Italy)

    2011-12-15

    Biodegradable magnesium alloy stents (MAS) can provide a great benefit for diseased vessels and avoid the long-term incompatible interactions between vessels and permanent stent platforms. However, the existing MAS showed insufficient scaffolding to the target vessels due to short degradation time. In this study, a three dimensional finite element model combined with a degradable material model of AZ31 (Al 0.03, Zn 0.01, Mn 0.002 and Mg balance, mass percentage) was applied to three different MAS designs including an already implanted stent (Stent A), an optimized design (Stent B) and a patented stent design (Stent C). One ring of each design was implanted through a simulation in a vessel model then degraded with the changing interaction between outer stent surface and the vessel. Results showed that a proper stent design (Stent B) can lead to an increase of nearly 120% in half normalized recoil time of the vessel compared to the Stent A; moreover, the expectation that the MAS design, with more mass and optimized mechanical properties, can increase scaffolding time was verified numerically. The Stent C has more materials than Stent B; however, it only increased the half normalized recoil time of the vessel by nearly 50% compared to the Stent A because of much higher stress concentration than that of Stent B. The 3D model can provide a convenient design and testing tool for novel magnesium alloy stents.

  7. Computer Simulation of the Mechanical Behaviour of Implanted Biodegradable Stents in a Remodelling Artery

    Science.gov (United States)

    Boland, Enda L.; Grogan, James A.; Conway, Claire; McHugh, Peter E.

    2016-04-01

    Coronary stents have revolutionised the treatment of coronary artery disease. While coronary artery stenting is now relatively mature, significant scientific and technological challenges still remain. One of the most fertile technological growth areas is biodegradable stents; here, there is the possibility to generate stents that will break down in the body once the initial necessary scaffolding period is past (6-12 months) (Grogan et al. in Acta Biomater 7:3523, 2011) and when the artery has remodelled (including the formation of neo-intima). A stent angioplasty computational test-bed has been developed by the authors, based on the Abaqus software (DS-SIMULIA, USA), capable of simulating stent tracking, balloon expansion, recoil and in vivo loading in a atherosclerotic artery model. Additionally, a surface corrosion model to simulate uniform and pitting corrosion of biodegradable stents and a representation of the active response of the arterial tissue following stent implantation, i.e. neointimal remodelling, has been developed. The arterial neointimal remodelling simulations with biodegradable stent corrosion demonstrate that the development of new arterial tissue around the stent struts has a substantial effect on the mechanical behaviour of degrading stents.

  8. Fabrication and Optimal Design of Biodegradable Polymeric Stents for Aneurysms Treatments.

    Science.gov (United States)

    Han, Xue; Wu, Xia; Kelly, Michael; Chen, Xiongbiao

    2017-02-28

    An aneurysm is a balloon-like bulge in the wall of blood vessels, occurring in major arteries of the heart and brain. Biodegradable polymeric stent-assisted coiling is expected to be the ideal treatment of wide-neck complex aneurysms. This paper presents the development of methods to fabricate and optimally design biodegradable polymeric stents for aneurysms treatment. Firstly, a dispensing-based rapid prototyping (DBRP) system was developed to fabricate coil and zigzag structures of biodegradable polymeric stents. Then, compression testing was carried out to characterize the radial deformation of the stents fabricated with the coil or zigzag structure. The results illustrated the stent with a zigzag structure has a stronger radial stiffness than the one with a coil structure. On this basis, the stent with a zigzag structure was chosen for the development of a finite element model for simulating the real compression tests. The result showed the finite element model of biodegradable polymeric stents is acceptable within a range of radial deformation around 20%. Furthermore, the optimization of the zigzag structure was performed with ANSYS DesignXplorer, and the results indicated that the total deformation could be decreased by 35.7% by optimizing the structure parameters, which would represent a significant advance of the radial stiffness of biodegradable polymeric stents.

  9. Biodegradable Metals for Cardiovascular Stents: from Clinical Concerns to Recent Zn-Alloys.

    Science.gov (United States)

    Bowen, Patrick K; Shearier, Emily R; Zhao, Shan; Guillory, Roger J; Zhao, Feng; Goldman, Jeremy; Drelich, Jaroslaw W

    2016-05-01

    Metallic stents are used to promote revascularization and maintain patency of plaqued or damaged arteries following balloon angioplasty. To mitigate the long-term side effects associated with corrosion-resistant stents (i.e., chronic inflammation and late stage thrombosis), a new generation of so-called "bioabsorbable" stents is currently being developed. The bioabsorbable coronary stents will corrode and be absorbed by the artery after completing their task as vascular scaffolding. Research spanning the last two decades has focused on biodegradable polymeric, iron-based, and magnesium-based stent materials. The inherent mechanical and surface properties of metals make them more attractive stent material candidates than their polymeric counterparts. A third class of metallic bioabsorbable materials that are based on zinc has been introduced in the last few years. This new zinc-based class of materials demonstrates the potential for an absorbable metallic stent with the mechanical and biodegradation characteristics required for optimal stent performance. This review compares bioabsorbable materials and summarizes progress towards bioabsorbable stents. It emphasizes the current understanding of physiological and biological benefits of zinc and its biocompatibility. Finally, the review provides an outlook on challenges in designing zinc-based stents of optimal mechanical properties and biodegradation rate.

  10. Biodegradable polymeric stents for vascular application in a porcine carotid artery model: English version.

    Science.gov (United States)

    Kischkel, S; Grabow, N; Püschel, A; Erdle, B; Kabelitz, M; Martin, D P; Williams, S F; Bombor, I; Sternberg, K; Schmitz, K-P; Schareck, W; Bünger, C M

    Over the past years the development of biodegradable polymeric stents has made great progress; nevertheless, essential problems must still be solved. Modifications in design and chemical composition should optimize the quality of biodegradable stents and remove the weaknesses. New biodegradable poly-L-lactide/poly-4-hydroxybutyrate (PLLA/P4HB) stents and permanent 316L stents were implantedendovascularly into both common carotid arteries of 10 domestic pigs. At 4 weeks following implantation, computed tomography (CT) angiography was carried out to identify the distal degree of stenosis. The PLLA/P4HB group showed a considerably lower distal degree of stenosis by additional oral application of atorvastatin (mean 39.81 ± 8.57 %) compared to the untreated PLLA/P4HB group without atorvastatin (mean 52.05 ± 5.80 %). The 316L stents showed no differences in the degree of distal stenosis between the group treated with atorvastatin (mean 44.21 ± 2.34 %) and the untreated group (mean 35.65 ± 3.72 %). Biodegradable PLLA/P4HB stents generally represent a promising approach to resolving the existing problems in the use of permanent stents. Restitutio ad integrum is only achievable if a stent is completely degraded.

  11. Ketoprofen-eluting biodegradable ureteral stents by CO2 impregnation: In vitro study.

    Science.gov (United States)

    Barros, Alexandre A; Oliveira, Carlos; Reis, Rui L; Lima, Estevão; Duarte, Ana Rita C

    2015-11-30

    Ureteral stents are indispensable tools in urologic practice. The main complications associated with ureteral stents are dislocation, infection, pain and encrustation. Biodegradable ureteral stents are one of the most attractive designs with the potential to eliminate several complications associated with the stenting procedure. In this work we hypothesize the impregnation of ketoprofen, by CO2-impregnation in a patented biodegradable ureteral stent previously developed in our group. The biodegradable ureteral stents with each formulation: alginate-based, gellan gum-based were impregnated with ketoprofen and the impregnation conditions tested were 100 bar, 2 h and three different temperatures (35 °C, 40 °C and 50 °C). The impregnation was confirmed by FTIR and DSC demonstrated the amorphization of the drug upon impregnation. The in vitro elution profile in artificial urine solution (AUS) during degradation of a biodegradable ureteral stent loaded with ketoprofen was evaluated. According to the kinetics results these systems have shown to be very promising for the release ketoprofen in the first 72 h, which is the necessary time for anti-inflammatory delivery after the surgical procedure. The in vitro release studied revealed an influence of the temperature on the impregnation yield, with a higher impregnation yield at 40 °C. Higher yields were also obtained for gellan gum-based stents. The non-cytotoxicity characteristic of the developed ketoprofen-eluting biodegradable ureteral stents was evaluated in L929 cell line by MTS assay which demonstrated the feasibility of this product as a medical device.

  12. Randomized clinical trial comparing abluminal biodegradable polymer sirolimus-eluting stents with durable polymer sirolimus-eluting stents

    Science.gov (United States)

    Zhang, Haijun; Wang, Xiangfei; Deng, Wei; Wang, Shenguo; Ge, Junbo; Toft, Egon

    2016-01-01

    Abstract Background: The biodegradable polymer drug-eluting stents (DES) were developed to improve vascular healing. However, further data and longer-term follow-up are needed to confirm safety and efficacy of these stents. This randomized clinical trial aimed to compare safety and efficacy of 2 sirolimus-eluting stents (SES): Cordimax—a novel abluminal biodegradable polymer SES and Cypher Select—a durable polymer SES, at 9 months angiographic and 5-year clinical follow-up. Methods: We randomized 402 patients with coronary artery disease to percutaneous coronary intervention with Cordimax (n = 202) or Cypher select (n = 200). Angiographic follow-up was performed at 9 months after the index procedure and clinical follow-up annually up to 5 years. The primary endpoint was angiographic in-stent late luminal loss (LLL). Secondary endpoints included angiographic restenosis rate, target vessel revascularization (TVR), and major adverse cardiac events (MACEs; defined as cardiac death, myocardial infarction, or TVR) at 5-year follow-up. Results: Cordimax was noninferior to Cypher select for in-stent LLL (0.25 ± 0.47 vs 0.18 ± 0.49 mm; P = 0.587) and in-stent mean diameter stenosis (22.19 ± 12.21% vs 19.89 ± 10.79%; P = 0.064) at 9 months angiographic follow-up. The MACE rates were not different at 1 year (5.9% vs 4.0%, P = 0.376); however, MACE rates from 2 to 5 years were lower in the Cordimax group (6.8% vs 13.1%; P = 0.039). Conclusion: Abluminal biodegradable polymer SES is noninferior to durable polymer SES at 9-month angiographic and 1-year clinical follow-up. However, MACE rates from 2 to 5 years were less in the abluminal biodegradable polymer group. PMID:27661023

  13. Surgical management of Stenson’s duct injury by using double J stent urethral catheter

    Directory of Open Access Journals (Sweden)

    Suha N. Aloosi

    2015-01-01

    Conclusions: Herein, we described an easy yet efficient technique in management of parotid duct injury using a JJ stent which is often used for urethra. We think that use of JJ stent is a valuable technique to be used in the diagnosis and surgical repair of the parotid duct during traumatic facial and/or parotid injuries.

  14. Zotarolimus-eluting durable-polymer-coated stent versus a biolimus-eluting biodegradable-polymer-coated stent in unselected patients undergoing percutaneous coronary intervention (SORT OUT VI)

    DEFF Research Database (Denmark)

    Raungaard, Bent; Jensen, Lisette Okkels; Tilsted, Hans-Henrik

    2015-01-01

    BACKGROUND: New-generation drug-eluting coronary stents have reduced the risk of coronary events, especially in patients with complex disease or lesions. To what extent different stent platforms, polymers, and antiproliferative drugs affect outcomes, however, is unclear. We investigated the safety...... and efficacy of a third-generation stent by comparing a highly biocompatible durable-polymer-coated zotarolimus-eluting stent with a biodegradable-polymer-coated biolimus-eluting stent. METHODS: This open-label, randomised, multicentre, non-inferiority trial was done at three sites across western Denmark. All....... The trial was powered to assess non-inferiority of durable-polymer zotarolimus-eluting stent compared with the biodegradable-polymer biolimus-eluting stent with a predetermined non-inferiority margin of 0·025. This trial is registered with ClinicalTrials.gov, number NCT01956448. FINDINGS: Of 7103 screened...

  15. Woven polydioxanone biodegradable stents: a new treatment option for benign and malignant oesophageal strictures

    Energy Technology Data Exchange (ETDEWEB)

    Stivaros, S.M.; Williams, L.R.; Senger, C.; Laasch, Hans-Ulrich [Christie NHS Foundation Trust, Department of Radiology, Manchester (United Kingdom); Wilbraham, L. [Christie NHS Foundation Trust, Department of Nutrition and Dietetics, Manchester (United Kingdom)

    2010-05-15

    We present our initial experience with a new biodegradable (BD) esophageal stent in two patients, one for a therapy-resistant benign esophageal stricture, and the other as a temporary measure during curative radiotherapy for oesophageal carcinoma. The BD stents need to be loaded into a conventional pull-back delivery system but are then placed in a standard fashion. Pre-dilatation should be avoided to reduce the risk of migration, however if migration occurs the stents can be left to dissolve in the stomach. The stents are radiolucent but easily identified on CT with minimal artefact and thus might even aid with radiotherapy planning. BD stents offer an exciting new strategy for therapy-resistant benign strictures as well as a supportive measure for oesophageal cancer undergoing non-surgical treatment. (orig.)

  16. Fabrication of a Knitted Biodegradable Stents for Tracheal Regeneration

    Institute of Scientific and Technical Information of China (English)

    李毅; 张佩华; 冯勋伟

    2004-01-01

    Endoluminal stents for reinforcement and regeneration of human trachea have been developed by weft-knitting method on a small-diameter circular knitting machine. The constituent materials of the stent are Polyglactin, Polypropylene and Chitosan with Polyglactin and Polypropylene plate-stitched fabric acting as backbone while chitosan as matrix, respectively. The fabrication procedures including knitting and coating are described in this paper. Mechanical and animal tests have been carried out to evaluate the mechanical properties of the stents.

  17. Biodegradable-Polymer Biolimus-Eluting Stents versus Durable-Polymer Everolimus-Eluting Stents at One-Year Follow-Up: A Registry-Based Cohort Study.

    Science.gov (United States)

    Parsa, Ehsan; Saroukhani, Sepideh; Majlessi, Fereshteh; Poorhosseini, Hamidreza; Lofti-Tokaldany, Masoumeh; Jalali, Arash; Salarifar, Mojtaba; Nematipour, Ebrahim; Alidoosti, Mohammad; Aghajani, Hassan; Amirzadegan, Alireza; Kassaian, Seyed Ebrahim

    2016-04-01

    We compared outcomes of percutaneous coronary intervention patients who received biodegradable-polymer biolimus-eluting stents with those who received durable-polymer everolimus-eluting stents. At Tehran Heart Center, we performed a retrospective analysis of the data from January 2007 through December 2011 on 3,270 consecutive patients with coronary artery disease who underwent percutaneous coronary intervention with the biodegradable-polymer biolimus-eluting stent or the durable-polymer everolimus-eluting stent. We excluded patients with histories of coronary artery bypass grafting or percutaneous coronary intervention, acute ST-segment-elevation myocardial infarction, or the implantation of 2 different stent types. Patients were monitored for 12 months. The primary endpoint was a major adverse cardiac event, defined as a composite of death, nonfatal myocardial infarction, and target-vessel and target-lesion revascularization. Durable-polymer everolimus-eluting stents were implanted in 2,648 (81%) and biodegradable-polymer biolimus-eluting stents in 622 (19%) of the study population. There was no significant difference between the 2 groups (2.7% vs 2.7%; P=0.984) in the incidence of major adverse cardiac events. The cumulative adjusted probability of major adverse cardiac events in the biodegradable-polymer biolimus-eluting stent group did not differ from that of such events in the durable-polymer everolimus-eluting stent group (hazard ratio=0.768; 95% confidence interval, 0.421-1.44; P=0.388). We conclude that in our patients the biodegradable-polymer biolimus-eluting stent was as effective and safe, during the 12-month follow-up period, as was the durable-polymer everolimus-eluting stent.

  18. The twelve-month outcomes of a biolimus eluting stent with a biodegradable polymer compared with a sirolimus eluting stent with a durable polymer

    NARCIS (Netherlands)

    S.A. Garg (Scot); G. Sarno (Giovanna); P.W.J.C. Serruys (Patrick); T. de Vries (Ton); P. Buszman (Pawel); A. Linke (Axel); T. Ischinger (Thomas); V. Klauss (Volker); F.R. Eberli (Franz Robert); R. Corti (Roberto); W. Wijns (William); M-C. Morice (Marie-Claude); C. di Mario (Carlo); R.J.M. van Geuns (Robert Jan); P. Eerdmans (Pedro); G.A. van Es (Gerrit Anne); B. Meier (Bernard); P. Jùni (Peter); S. Windecker (Stephan)

    2010-01-01

    textabstractAims: This study reports the 12-month clinical outcomes of the LEADERS clinical trial which compared a biolimus eluting stent with a biodegradable polymer (BES) to a sirolimus eluting stent with a durable polymer (SES). Methods and results: The multicentre LEADERS trial employed an all-c

  19. Blood compatibility of a ferulic acid (FA)-eluting PHBHHx system for biodegradable magnesium stent application.

    Science.gov (United States)

    Zhang, Erlin; Shen, Feng

    2015-01-01

    Magnesium stent has shown potential application as a new biodegradable stent. However, the fast degradation of magnesium stent limited its clinic application. Recently, a biodegradable and drug-eluting coating system was designed to prevent magnesium from fast degradation by adding ferulic acid (FA) in poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) by a physical method. In vitro study has demonstrated that the FA-eluting system exhibited strong promotion to the endothelialization, which might be a choice for the stent application. In this paper, the hemolysis rate, the plasma recalcification time (PRT), the plasma prothrombin time (PT) and the kinetic clotting time of the FA-eluting films were investigated and the platelet adhesion was observed in order to assess the blood compatibility of the FA-eluting PHBHHx films in comparison with PHBHHx film. The results have shown that the addition of FA had no influence on the hemolysis, but prolonged PRT, PT and the clotting time and reduced the platelet adhesion and activation, displaying that the FA-eluting PHBHHx exhibited better blood compatibility than PHBHHx. In addition, the effect of alkali treatment on the blood compatibility of FA-eluting PHBHHx was also studied. It was indicated that alkali treatment had no effect on the hemolysis and the coagulation time, but enhanced slightly the platelet adhesion. All these demonstrated that FA-eluting PHBHHx film had good blood compatibility and might be a candidate surface coating for the biodegradable magnesium stent.

  20. The Ultimaster Biodegradable-Polymer Sirolimus-Eluting Stent: An Updated Review of Clinical Evidence.

    Science.gov (United States)

    Chisari, Alberto; Pistritto, Anna Maria; Piccolo, Raffaele; La Manna, Alessio; Danzi, Gian Battista

    2016-09-06

    The Ultimaster coronary stent system (Terumo Corporation, Tokyo, Japan) represents a new iteration in drug-eluting stent (DES) technology that has recently received the Conformité Européenne (CE) mark approval for clinical use. The Ultimaster is a thin-strut, cobalt chromium, biodegradable-polymer, sirolimus-eluting coronary stent. The high elasticity of the biodegradable-polymer (PDLLA-PCL) and the abluminal gradient coating technology are additional novel features of this coronary device. The Ultimaster DES has undergone extensive clinical evaluation in two studies: The CENTURY I and II trials. Results from these two landmark studies suggested an excellent efficacy and safety profile of the Ultimaster DES across several lesion and patient subsets, with similar clinical outcomes to contemporary, new-generation DES. The aim of this review is to summarize the rationale behind this novel DES technology and to provide an update of available evidence about the clinical performance of the Ultimaster DES.

  1. Surgical management of Stenson’s duct injury by using double J stent urethral catheter

    Science.gov (United States)

    Aloosi, Suha N.; Khoshnaw, Najmaddin; Ali, Shakhawan M.; Muhammad, Belal A.

    2015-01-01

    Background Parotid duct or gland injury can be caused by assault with a knife, bottle, electrical-saw, road traffic accident, or rarely gunshot and fractures of the facial skeleton. The injury can be in the form of laceration, ductal exposure, total cutting, or crushing of the duct. These conditions are difficult to diagnose because of complex anatomy and variable forms of the injury. A successful management of parotid duct injuries depends on early diagnosis and appropriate intervention; improper surgery may lead to complications such as sialocele or salivary fistula Case report A 27-years-old man was presented to the maxillofacial unit, complaining of bleeding over the right side of his face after accidental exposure to a chain-saw three hours before admission. On examination, a 6 cm deep lacerated wound was found over the right buccal area, suspecting facial nerve-buccal branch and parotid duct injury. Under general anesthesia the parotid duct injury diagnosed, microsurgical anastomosis of the cut-ends of the parotid duct performed using the double J catheter. Sutures and JJ stent removed seven and twenty postoperative days respectively. After a proper supportive treatment a complete healing of the duct was obtained with normal amount of saliva. Conclusions Herein, we described an easy yet efficient technique in management of parotid duct injury using a JJ stent which is often used for urethra. We think that use of JJ stent is a valuable technique to be used in the diagnosis and surgical repair of the parotid duct during traumatic facial and/or parotid injuries. PMID:26555062

  2. Usefulness of biodegradable stents constructed of poly-/-lactic acid monofilaments in patients with benign esophageal stenosis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To report 13 patients with benign esophageal stenosis treated with the biodegradable stent.METHODS: We developed a Ultraflex-type stent by knitting poly-l-lactic acid monofilaments.RESULTS: Two cases were esophageal stenosis caused by drinking of caustic liquid, 4 cases were due to surgical resection of esophageal cancers, and 7 cases were patients with esophageal cancer who received the preventive placement of biodegradable stents for postendoscopic mucosal dissection (ESD) stenosis. The preventive placement was performed within 2 to 3 d after ESD. In 10 of the 13 cases, spontaneous migration of the stents occurred between 10 to 21 d after placement. In these cases, the migrated stents were excreted with the feces, and no obstructive complications were experienced. In 3 cases, the stents remained at the proper location on d 21 after placement. No symptoms of re-stenosis were observed within the follow-up period of 7 mo to 2 years. Further treatment with balloon dilatation or replacement of the biodegradable stent was not required.CONCLUSION: Biodegradable stents were useful for the treatment of benign esophageal stenosis, particularly for the prevention of post-ESD stenosis.

  3. The outcome of bifurcation lesion stenting using a biolimus-eluting stent with a bio-degradable polymer compared to a sirolimus-eluting stent with a durable polymer

    NARCIS (Netherlands)

    S.A. Garg (Scot); J.J. Wykrzykowska (Joanna); T. de Vries (Ton); P. Buszman (Pawel); T. de Vries (Ton); S. Trznadel (Stanislaw); A. Linke (Axel); K. Lenk (Karsten); T. Ischinger (Thomas); V. Klauss (Volker); F.R. Eberli (Franz Robert); R. Corti (Roberto); W. Wijns (William); M-C. Morice (Marie-Claude); C. di Mario (Carlo); P. Tyczynski (Pawel); R.J.M. van Geuns (Robert Jan); P. Eerdmans (Pedro); G.A. van Es (Gerrit Anne); B. Meier (Bernard); P. Jùni (Peter); S. Windecker (Stephan)

    2011-01-01

    textabstractAims: This study investigated the differences in clinical outcomes between patients with bifurcation lesions (BL) treated with a biolimus-eluting stent (BES) with a biodegradable polymer, and a sirolimus-eluting stent (SES) with a durable polymer. Methods and results: The clinical outcom

  4. Forming of magnesium alloy microtubes in the fabrication of biodegradable stents

    Institute of Scientific and Technical Information of China (English)

    Lixiao Wang; Gang Fang; Lingyun Qian; Sander Leeflang; Jurek Duszczyk; Jie Zhou

    2014-01-01

    Magnesium alloys have, in recent years, been recognized as highly promising biodegradable materials, especially for vascular stent applications. Forming of magnesium alloys into high-precision thin-wall tubes has however presented a technological barrier in the fabrication of vascular stents, because of the poor workability of magnesium at room temperature. In the present study, the forming processes, i.e., hot indirect extrusion and multi-pass cold drawing were used to fabricate seamless microtubes of a magnesium alloy. The magnesium alloy ZM21 was selected as a representative biomaterial for biodegradable stent applications. Microtubes with an outside diameter of 2.9 mm and a wall thickness of 0.2 mm were successfully produced at the fourth pass of cold drawing without inter-pass annealing. Dimensional evaluation showed that multi-pass cold drawing was effective in correcting dimensional non-uniformity arising from hot indirect extrusion. Examinations of the microstructures of microtubes revealed the generation of a large number of twins as a result of accumulated work hardening at the third and fourth passes of cold drawing, corresponding to the significantly raised forming forces. The work demonstrated the viability of the forming process route selected for the fabrication of biodegradable magnesium alloy microtubes.

  5. A Wireless Pressure Sensor Integrated with a Biodegradable Polymer Stent for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Jongsung Park

    2016-06-01

    Full Text Available This paper describes the fabrication and characterization of a wireless pressure sensor for smart stent applications. The micromachined pressure sensor has an area of 3.13 × 3.16 mm2 and is fabricated with a photosensitive SU-8 polymer. The wireless pressure sensor comprises a resonant circuit and can be used without the use of an internal power source. The capacitance variations caused by changes in the intravascular pressure shift the resonance frequency of the sensor. This change can be detected using an external antenna, thus enabling the measurement of the pressure changes inside a tube with a simple external circuit. The wireless pressure sensor is capable of measuring pressure from 0 mmHg to 230 mmHg, with a sensitivity of 0.043 MHz/mmHg. The biocompatibility of the pressure sensor was evaluated using cardiac cells isolated from neonatal rat ventricular myocytes. After inserting a metal stent integrated with the pressure sensor into a cardiovascular vessel of an animal, medical systems such as X-ray were employed to consistently monitor the condition of the blood vessel. No abnormality was found in the animal blood vessel for approximately one month. Furthermore, a biodegradable polymer (polycaprolactone stent was fabricated with a 3D printer. The polymer stent exhibits better sensitivity degradation of the pressure sensor compared to the metal stent.

  6. Fibre Laser Cutting and Chemical Etching of AZ31 for Manufacturing Biodegradable Stents

    Directory of Open Access Journals (Sweden)

    Ali Gökhan Demir

    2013-01-01

    Full Text Available The use of magnesium-alloy stents shows promise as a less intrusive solution for the treatment of cardiovascular pathologies as a result of the high biocompatibility of the material and its intrinsic dissolution in body fluids. However, in addition to requiring innovative solutions in material choice and design, these stents also require a greater understanding of the manufacturing process to achieve the desired quality with improved productivity. The present study demonstrates the manufacturing steps for the realisation of biodegradable stents in AZ31 magnesium alloy. These steps include laser microcutting with a Q-switched fibre laser for the generation of the stent mesh and subsequent chemical etching for the cleaning of kerf and surface finish. Specifically, for the laser microcutting step, inert and reactive gas cutting conditions were compared. The effect of chemical etching on the reduction in material thickness, as well as on spatter removal, was also evaluated. Prototype stents were produced, and the material composition and surface quality were characterised. The potentialities of combining nanosecond laser microcutting and chemical etching are shown and discussed.

  7. A Wireless Pressure Sensor Integrated with a Biodegradable Polymer Stent for Biomedical Applications.

    Science.gov (United States)

    Park, Jongsung; Kim, Ji-Kwan; Patil, Swati J; Park, Jun-Kyu; Park, SuA; Lee, Dong-Weon

    2016-06-02

    This paper describes the fabrication and characterization of a wireless pressure sensor for smart stent applications. The micromachined pressure sensor has an area of 3.13 × 3.16 mm² and is fabricated with a photosensitive SU-8 polymer. The wireless pressure sensor comprises a resonant circuit and can be used without the use of an internal power source. The capacitance variations caused by changes in the intravascular pressure shift the resonance frequency of the sensor. This change can be detected using an external antenna, thus enabling the measurement of the pressure changes inside a tube with a simple external circuit. The wireless pressure sensor is capable of measuring pressure from 0 mmHg to 230 mmHg, with a sensitivity of 0.043 MHz/mmHg. The biocompatibility of the pressure sensor was evaluated using cardiac cells isolated from neonatal rat ventricular myocytes. After inserting a metal stent integrated with the pressure sensor into a cardiovascular vessel of an animal, medical systems such as X-ray were employed to consistently monitor the condition of the blood vessel. No abnormality was found in the animal blood vessel for approximately one month. Furthermore, a biodegradable polymer (polycaprolactone) stent was fabricated with a 3D printer. The polymer stent exhibits better sensitivity degradation of the pressure sensor compared to the metal stent.

  8. Stent selection in patients with myocardial infarction: drug eluting, biodegradable polymers or bare metal stents?

    Science.gov (United States)

    Mieres, Juan; Rodríguez, Alfredo E

    2012-08-01

    Percutaneous coronary intervention (PCI) has been increasingly used in the last years during interventional procedures in patients with acute coronary syndromes (ACS) including ST elevation myocardial infarction (STEMI) and non-ST elevation myocardial infarction (NSTEMI). In patients with either STEMI, NSTEMI, high risk ACS with EKG changes or cardiac enzymes rises; PCI with bare metal stent (BMS) implantation has been associated with a significant improvement in clinical outcome. Therefore, BMS implantation during primary PCI in STEMI has become a standard of practice. With the introduction of drug eluting stents (DESs) in this decade, the use of these new devices instead of BMSs in patients with STEMI has emerged as a rational PCI alternative in this particular subgroup of patients. In spite of the unquestionable benefits of DESs in terms of reduction of restenosis and TVR, specific concerns have arisen with regard to their long-term safety. High incidence of very late stent thrombosis has been described with these devices, and special attention should be paid in patients with unstable coronary lesions, in which plaque composition and remodeling may play a main role in their safety and long-term outcome. Intraluminal thrombus caused by plaque rupture is the most frequent mechanism of STEMI, in which the necrotic core and thin fibrous cap play a major role. In this context, the use of first DESs designs may be futile or even unsafe because delayed healing may further contribute to plaque instability. Adjunctive invasive imaging tools can improve stent deployment and safety outcome in these lesions with intravascular findings of plaque instability. Recently, other players such as new dedicated antithrombotic BMS designs, including selfexpanding stents or drug-eluting coated balloons, are exploring their potential indications in patients with ACS and myocardial infarction. This paper reports and discusses new stent devices and adjunctive pharmacologic agents. It

  9. Novel Zn-based alloys for biodegradable stent applications: Design, development and in vitro degradation.

    Science.gov (United States)

    Mostaed, E; Sikora-Jasinska, M; Mostaed, A; Loffredo, S; Demir, A G; Previtali, B; Mantovani, D; Beanland, R; Vedani, M

    2016-07-01

    The search for a degradable metal simultaneously showing mechanical properties equal or higher to that of stainless steel and uniform degradation is still an open challenge. Several magnesium-based alloys have been studied, but their degradation rate has proved to be too fast and rarely homogeneous. Fe-based alloys show appropriate mechanical properties but very low degradation rate. In the present work, four novel Zn-Mg and two Zn-Al binary alloys were investigated as potential biodegradable materials for stent applications. The alloys were developed by casting process and homogenized at 350°C for 48h followed by hot extrusion at 250°C. Tube extrusion was performed at 300°C to produce tubes with outer/inner diameter of 4/1.5mm as precursors for biodegradable stents. Corrosion tests were performed using Hanks׳ modified solution. Extruded alloys exhibited slightly superior corrosion resistance and slower degradation rate than those of their cast counterparts, but all had corrosion rates roughly half that of a standard purity Mg control. Hot extrusion of Zn-Mg alloys shifted the corrosion regime from localized pitting to more uniform erosion, mainly due to the refinement of second phase particles. Zn-0.5Mg is the most promising material for stent applications with a good combination of strength, ductility, strain hardening exponent and an appropriate rate of loss of mechanical integrity during degradation. An EBSD analysis in the vicinity of the laser cut Zn-0.5Mg tube found no grain coarsening or texture modification confirming that, after laser cutting, the grain size and texture orientation of the final stent remains unchanged. This work shows the potential for Zn alloys to be considered for stent applications.

  10. Research on a Zn-Cu alloy as a biodegradable material for potential vascular stents application.

    Science.gov (United States)

    Niu, Jialin; Tang, Zibo; Huang, Hua; Pei, Jia; Zhang, Hua; Yuan, Guangyin; Ding, Wenjiang

    2016-12-01

    Zn-based alloys have been viewed as new potential materials for biodegradable implants, such as cardiovascular stents, mainly in consideration of their lower corrosion rate when compared with that of Mg alloys. In this study we developed a new Zinc-4wt.%Copper (Zn-4Cu) alloy as a biodegradable material. Hot extrusion was applied to Zn-4Cu to refine the microstructure and consequently improve its mechanical properties and corrosion resistance. After extrusion, dendritic CuZn5 phases were broken and distributed along the extrusion direction. The grains were refined obviously due to dynamical recrystallization. The yield strength (YS), ultimate tensile strength (UTS) and elongation of the as-extruded alloy are 250±10MPa, 270±10MPa and 51±2%, respectively. The corrosion rate of the as-extruded alloy in Hank's solution is about 9.41(±1.34)μmyear(-1). In vitro evaluation shows that Zn-4Cu presents acceptable toxicity to human endothelial cells, and could effectively inhibit bacteria adhesion and biofilm formation. The present study indicates that the as-extruded Zn-4Cu alloy exhibits excellent strength and ductility, uniform and slow degradation, good biocompatibility and significant antibacterial effect, which make it an excellent candidate material for biodegradable implants, especially for cardiovascular stents application.

  11. Six-month results of a biodegradable polymer and rapamycin-coating stent for coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    Yuxiao ZHANG; Caiyi LU; Qiao XUE; Peng LIU; Wei YAN; Rui CHEN

    2006-01-01

    Objective To assess the safety and efficacy of a novel biodegradable polymer and rapamycin-coating stent, the EXCEL stent, in the treatment of coronary artery disease (CAD), as compared with the CypherTM stent. Methods In this prospective, non-randomized study, 60 consecutive patients with symptomatic CAD received either an EXCEL stent (n=32), or a CypherTM stent(n=28),according to their respective treatment intention. Follow-up angiography was performed at a mean of 180±40 days. The primary endpoint of the study was the occurrence of a major adverse cardiac event (MACE), including death, myocardial infarction, or target-vessel revascularization during the 6 months after stenting. The secondary end points included the in-stent late luminal loss (LLL), percentage of in-stent stenosis of the luminal diameter, and the rate of restenosis (luminal narrowing of 50 percent or more) at 6 months. Results There were no significant differences between the two groups in baseline characteristics, including the distribution of target vessel and lesion types. During the follow up period of 6 months, there were no occurrences of MACE in either group. Twenty-seven patients(84%) in the EXCEL group and 10 (36 %) in the CypherTM group underwent quantitative coronary angiography at 6 months. For these patients, no restenosis occurred, and there were no differences in the in-stent stenosis of the luminal diameter (5.98±5.52% vs 5.21 ±6.3%,P>0.05) and the LLL (-0.02±0.09 mm vs -0.01±0.07 mm, P>0.05). Conclusions Compared with the CypherTM stent, the EXCEL Stent with biodegradable polymer and rapamycin-coating showed similar efficacy in the prevention of neointimal proliferation, restenosis, and associated clinical events in CAD patients.

  12. Fe-Mn alloys for metallic biodegradable stents: degradation and cell viability studies.

    Science.gov (United States)

    Hermawan, Hendra; Purnama, Agung; Dube, Dominique; Couet, Jacques; Mantovani, Diego

    2010-05-01

    Biodegradable stents have shown their potential to be a valid alternative for the treatment of coronary artery occlusion. This new class of stents requires materials having excellent mechanical properties and controllable degradation behaviour without inducing toxicological problems. The properties of the currently considered gold standard material for stents, stainless steel 316L, were approached by new Fe-Mn alloys. The degradation characteristics of these Fe-Mn alloys were investigated including in vitro cell viability. A specific test bench was used to investigate the degradation in flow conditions simulating those of coronary artery. A water-soluble tetrazolium test method was used to study the effect of the alloy's degradation product to the viability of fibroblast cells. These tests have revealed the corrosion mechanism of the alloys. The degradation products consist of metal hydroxides and calcium/phosphorus layers. The alloys have shown low inhibition to fibroblast cells' metabolic activities. It is concluded that they demonstrate their potential to be developed as degradable metallic biomaterials.

  13. Urethral Disorders

    Science.gov (United States)

    ... or injury. They include Urethral cancer - a rare cancer that happens more often in men Urethral stricture - a narrowing of the opening of the urethra Urethritis - inflammation of the urethra, sometimes caused by ...

  14. Biodegradable and elastomeric poly(glycerol sebacate) as a coating material for nitinol bare stent.

    Science.gov (United States)

    Kim, Min Ji; Hwang, Moon Young; Kim, JiHeung; Chung, Dong June

    2014-01-01

    We synthesized and evaluated biodegradable and elastomeric polyesters (poly(glycerol sebacate) (PGS)) using polycondensation between glycerol and sebacic acid to form a cross-linked network structure without using exogenous catalysts. Synthesized materials possess good mechanical properties, elasticity, and surface erosion biodegradation behavior. The tensile strength of the PGS was as high as 0.28 ± 0.004 MPa, and Young's modulus was 0.122 ± 0.0003 MPa. Elongation was as high as 237.8 ± 0.64%, and repeated elongation behavior was also observed to at least three times the original length without rupture. The water-in-air contact angles of the PGS surfaces were about 60°. We also analyzed the properties of an electrospray coating of biodegradable PGS on a nitinol stent for the purpose of enhancing long-term patency for the therapeutic treatment of varicose veins disease. The surface morphology and thickness of coating layer could be controlled by adjusting the electrospraying conditions and solution parameters.

  15. Biodegradable and Elastomeric Poly(glycerol sebacate as a Coating Material for Nitinol Bare Stent

    Directory of Open Access Journals (Sweden)

    Min Ji Kim

    2014-01-01

    Full Text Available We synthesized and evaluated biodegradable and elastomeric polyesters (poly(glycerol sebacate (PGS using polycondensation between glycerol and sebacic acid to form a cross-linked network structure without using exogenous catalysts. Synthesized materials possess good mechanical properties, elasticity, and surface erosion biodegradation behavior. The tensile strength of the PGS was as high as 0.28 ± 0.004 MPa, and Young's modulus was 0.122 ± 0.0003 MPa. Elongation was as high as 237.8 ± 0.64%, and repeated elongation behavior was also observed to at least three times the original length without rupture. The water-in-air contact angles of the PGS surfaces were about 60°. We also analyzed the properties of an electrospray coating of biodegradable PGS on a nitinol stent for the purpose of enhancing long-term patency for the therapeutic treatment of varicose veins disease. The surface morphology and thickness of coating layer could be controlled by adjusting the electrospraying conditions and solution parameters.

  16. The cold-rolling behaviour of AZ31 tubes for fabrication of biodegradable stents.

    Science.gov (United States)

    Zhang, Yaowu; Kent, Damon; Wang, Gui; StJohn, David; Dargusch, Matthew S

    2014-11-01

    Mg alloys are receiving considerable attention for biomedical stents due to their combination of good mechanical properties and high biodegradability. Cold rolling is necessary to process Mg alloy tubes before final drawing and fabrication of the magnesium stents. In this paper, cold-rolled tubes were subjected to a cross-sectional reduction rate (ε) of up to 19.7%, and were further processed at various ratios of wall-thickness to diameter reduction (Q) from 0 to 2.24 with a constant ε of 19.7%. The results show that the cold-rolled tubes exhibited a rise in ultimate tensile strength (UTS), yield strength (YS), and a reduction in elongation as ε increased from 5.5% to 19.7%. UTS, YS and elongation decreased when Q was increased from 0 to 2.24. Mechanical twinning was observed and analysed. Extension twins increased with increasing ε and were almost saturated at a ε of 16.5%. Extension twins play an important role in determining the evolution of mechanical behaviour in the case of increasing ε, whilst contraction/double twins and secondary extension twins have a large effect on mechanical behaviour in the case of varying Q. The results indicate that the proportions and types of twins play a major role in determining the mechanical behaviour of the AZ31 tubes.

  17. Biodegradable shape-memory block co-polymers for fast self-expandable stents.

    Science.gov (United States)

    Xue, Liang; Dai, Shiyao; Li, Zhi

    2010-11-01

    Block co-polymers PCTBVs (M(n) of 36,300-65,300 g/mol, T(m) of 39-40 and 142 degrees C) containing hyperbranched three-arm poly(epsilon-caprolactone) (PCL) as switching segment and microbial polyester PHBV as crystallizable hard segment were designed as biodegradable shape-memory polymer (SMP) for fast self-expandable stent and synthesized in 96% yield by the reaction of three-arm PCL-triol (M(n) of 4200 g/mol, T(m) of 47 degrees C) with methylene diphenyl 4,4'-diisocyanate isocynate (MDI) to form the hyperbrached MDI-linked PCL (PTCM; M(n) of 25,400 g/mol and a T(m) of 38 degrees C), followed by further polymerization with PHBV-diol (M(n) of 2200 g/mol, T(m) of 137 and 148 degrees C). The polymers were characterized by (1)H NMR, GPC, DSC, tensile test, and cyclic thermomechanical tensile test. PCTBVs showed desired thermal properties, mechanical properties, and ductile nature. PCTBV containing 25 wt% PHBV (PCTBV-25) demonstrated excellent shape-memory property at 40 degrees C, with R(f) of 94%, R(r) of 98%, and shape recovery within 25s. PCTBV-25 was also shown as a safe material with good biocompatibility by cytotoxicity tests and cell growth experiments. The stent made from PCTBV-25 film showed nearly complete self-expansion at 37 degrees C within only 25 s, which is much better and faster than the best known self-expandable stents.

  18. Efficacy and safety of biodegradable polymer biolimus-eluting stents versus durable polymer drug-eluting stents: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Yicong Ye

    Full Text Available BACKGROUNDS: Drug-eluting stents (DES with biodegradable polymers have been developed to address the risk of thrombosis associated with first-generation DES. We aimed to determine the efficacy and safety of biodegradable polymer biolimus-eluting stents (BES versus durable polymer DES. METHODS: Systematic database searches of MEDLINE (1950 to June 2013, EMBASE (1966 to June 2013, the Cochrane Central Register of Controlled Trials (Issue 6 of 12, June 2013, and a review of related literature were conducted. All randomized controlled trials comparing biodegradable polymer BES versus durable polymer DES were included. RESULTS: Eight randomized controlled trials investigating 11,015 patients undergoing percutaneous coronary interventions were included in the meta-analysis. The risk of major adverse cardiac events did not differ significantly between the patients treated with the biodegradable polymer BES and the durable polymer DES (Relative risk [RR], 0.970; 95% CI, 0.848-1.111; p = 0.662. However, biodegradable polymer BES was associated with reduced risk of very late ST compared with the durable polymer DES, while the risk of early or late ST was similar (RR for early or late ST, 1.167; 95% CI 0.755-1.802; p = 0.487; RR 0.273; 95% CI 0.115-0.652; p = 0.003; p for interaction = 0.003. CONCLUSIONS: In this meta-analysis of randomized controlled trials, treatments with biodegradable polymer BES did not significantly reduce the risk of major adverse cardiac events, but demonstrated a significantly lower risk of very late ST when compared to durable polymer DES. This conclusion requires confirmation by further studies with long-term follow-up. PROSPERO REGISTER NUMBER: http://www.crd.york.ac.uk/PROSPERO/display_record.asp?ID=CRD42013004364#.UnM2lfmsj6J.

  19. Electrospun PLGA/gelatin fibrous tubes for the application of biodegradable intestinal stent in rat model.

    Science.gov (United States)

    Son, So-Ra; Franco, Rose-Ann; Bae, Sang-Ho; Min, Young-Ki; Lee, Byong-Taek

    2013-08-01

    A biodegradable fibrous tube was fabricated by electrospinning method using a combination of Poly(lactic-co-glycolic acid) (PLGA) and gelatin dissolved in trifluoroethanol (TFE). Different ratios of the two polymers (PLGA/Gelatin: 1/9, 3/7, 5/5) were used for electrospinning to determine the optimum condition appropriate for intestinal stent application. Fiber morphology was visualized and analyzed using a scanning electron microscope (SEM). Characterizations of physical properties were done according to its tensile strength, surface hydrophilicity, swelling ability, and biodegradability. Biocompatibility of the scaffolds was investigated in vitro using IEC-18 (Rat intestinal epithelial cell). Cell proliferation was quantified using MTT assay and cell adhesion behavior was visualized by SEM and confocal laser scanning microscope. PLGA/Gelatin (5/5) was determined to have adequate material properties and sufficient in vitro biocompatibility. This was then implanted in a male Sprague-Dawley rat for 14 days to determine in vivo behavior of the sample. Histological examination on the intestinal tissue surrounding the graft showed normal morphology comparable to non-implanted intestine.

  20. Promoting endothelial recovery and reducing neointimal hyperplasia using sequential-like release of acetylsalicylic acid and paclitaxel-loaded biodegradable stents

    Directory of Open Access Journals (Sweden)

    Lee CH

    2014-08-01

    Full Text Available Cheng-Hung Lee,1,2 Chia-Ying Yu,2 Shang-Hung Chang,1 Kuo-Chun Hung,1 Shih-Jung Liu,2 Chao-Jan Wang,3 Ming-Yi Hsu,3 I-Chang Hsieh,1 Wei-Jan Chen,1 Yu-Shien Ko,1 Ming-Shien Wen1 1Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital-Linkou, Tao-Yuan, Taiwan; 2Department of Mechanical Engineering, Chang Gung University, Tao-Yuan, Taiwan; 3Department of Medical Imaging and Intervention, Chang Gung Memorial Hospital, Linkou, Tao-Yuan, Taiwan Introduction: This work reports on the development of a biodegradable dual-drug-eluting stent with sequential-like and sustainable drug-release of anti-platelet acetylsalicylic acid and anti-smooth muscle cell (SMC proliferative paclitaxel.Methods: To fabricate the biodegradable stents, poly-L-lactide strips are first cut from a solvent-casted film. They are rolled onto the surface of a metal pin to form spiral stents. The stents are then consecutively covered by acetylsalicylic acid and paclitaxel-loaded polylactide-polyglycolide nanofibers via electrospinning.Results: Biodegradable stents exhibit mechanical properties that are superior to those of metallic stents. Biodegradable stents sequentially release high concentrations of acetylsalicylic acid and paclitaxel for more than 30 and 60 days, respectively. In vitro, the eluted drugs promote endothelial cell numbers on days 3 and 7, and reduce the proliferation of SMCs in weeks 2, 4, and 8. The stents markedly inhibit the adhesion of platelets on days 3, 7, and 14 relative to a non-drug-eluting stent. In vivo, the implanted stent is intact, and no stent thrombosis is observed in the stent-implanted vessels without the administration of daily oral acetylsalicylic acid. Promotion of endothelial recovery and inhibition of neointimal hyperplasia are also observed on the stented vessels.Conclusion: The work demonstrates the efficiency and safety of the biodegradable dual-drug-eluting stents with sequential and sustainable drug release

  1. Zotarolimus-eluting durable-polymer-coated stent versus a biolimus-eluting biodegradable-polymer-coated stent in unselected patients undergoing percutaneous coronary intervention (SORT OUT VI): a randomised non-inferiority trial.

    Science.gov (United States)

    Raungaard, Bent; Jensen, Lisette Okkels; Tilsted, Hans-Henrik; Christiansen, Evald Høj; Maeng, Michael; Terkelsen, Christian Juhl; Krusell, Lars Romer; Kaltoft, Anne; Kristensen, Steen Dalby; Bøtker, Hans Erik; Thuesen, Leif; Aarøe, Jens; Jensen, Svend Eggert; Villadsen, Anton Boel; Thayssen, Per; Veien, Karsten Tange; Hansen, Knud Nørregaard; Junker, Anders; Madsen, Morten; Ravkilde, Jan; Lassen, Jens Flensted

    2015-04-18

    New-generation drug-eluting coronary stents have reduced the risk of coronary events, especially in patients with complex disease or lesions. To what extent different stent platforms, polymers, and antiproliferative drugs affect outcomes, however, is unclear. We investigated the safety and efficacy of a third-generation stent by comparing a highly biocompatible durable-polymer-coated zotarolimus-eluting stent with a biodegradable-polymer-coated biolimus-eluting stent. This open-label, randomised, multicentre, non-inferiority trial was done at three sites across western Denmark. All patients who presented with stable coronary artery disease or acute coronary syndromes and at least one coronary artery lesion (more than 50% stenosis) from March, 2011, to August, 2012, were assessed for eligibility. Patients were randomly assigned in a 1:1 ratio to receive either the durable-polymer zotarolimus-eluting stent or the biodegradable-polymer biolimus-eluting stent. The primary endpoint was a composite of safety (cardiac death and myocardial infarction not clearly attributable to a non-target lesion) and efficacy (target-lesion revascularisation) at 12 months, analysed by intention to treat. The trial was powered to assess non-inferiority of durable-polymer zotarolimus-eluting stent compared with the biodegradable-polymer biolimus-eluting stent with a predetermined non-inferiority margin of 0·025. This trial is registered with ClinicalTrials.gov, number NCT01956448. Of 7103 screened, 1502 patients with 1883 lesions were assigned to receive the durable-polymer zotarolimus-eluting stent and 1497 patients with 1791 lesions to receive the biodegradable-polymer biolimus-eluting stent. 79 (5·3%) and 75 (5·0%) patients, respectively, met the primary endpoint (absolute risk difference 0·0025, upper limit of one-sided 95% CI 0·016%; p=0·004). The individual components of the primary endpoint did not differ significantly between stent types at 12 months. The durable

  2. Local sustained delivery of acetylsalicylic acid via hybrid stent with biodegradable nanofibers reduces adhesion of blood cells and promotes reendothelialization of the denuded artery.

    Science.gov (United States)

    Lee, Cheng-Hung; Lin, Yu-Huang; Chang, Shang-Hung; Tai, Chun-Der; Liu, Shih-Jung; Chu, Yen; Wang, Chao-Jan; Hsu, Ming-Yi; Chang, Hung; Chang, Gwo-Jyh; Hung, Kuo-Chun; Hsieh, Ming-Jer; Lin, Fen-Chiung; Hsieh, I-Chang; Wen, Ming-Shien; Huang, Yenlin

    2014-01-01

    Incomplete endothelialization, blood cell adhesion to vascular stents, and inflammation of arteries can result in acute stent thromboses. The systemic administration of acetylsalicylic acid decreases endothelial dysfunction, potentially reducing thrombus, enhancing vasodilatation, and inhibiting the progression of atherosclerosis; but, this is weakened by upper gastrointestinal bleeding. This study proposes a hybrid stent with biodegradable nanofibers, for the local, sustained delivery of acetylsalicylic acid to injured artery walls. Biodegradable nanofibers are prepared by first dissolving poly(D,L)-lactide-co-glycolide and acetylsalicylic acid in 1,1,1,3,3,3-hexafluoro-2-propanol. The solution is then electrospun into nanofibrous tubes, which are then mounted onto commercially available bare-metal stents. In vitro release rates of pharmaceuticals from nanofibers are characterized using an elution method, and a highperformance liquid chromatography assay. The experimental results suggest that biodegradable nanofibers release high concentrations of acetylsalicylic acid for three weeks. The in vivo efficacy of local delivery of acetylsalicylic acid in reducing platelet and monocyte adhesion, and the minimum tissue inflammatory reaction caused by the hybrid stents in treating denuded rabbit arteries, are documented. The proposed hybrid stent, with biodegradable acetylsalicylic acid-loaded nanofibers, substantially contributed to local, sustained delivery of drugs to promote re-endothelialization and reduce thrombogenicity in the injured artery. The stents may have potential applications in the local delivery of cardiovascular drugs. Furthermore, the use of hybrid stents with acetylsalicylic acid-loaded nanofibers that have high drug loadings may provide insight into the treatment of patients with high risk of acute stent thromboses.

  3. Biodegradable polymer Biolimus-eluting stent (Nobori® for the treatment of coronary artery lesions: review of concept and clinical results

    Directory of Open Access Journals (Sweden)

    Schurtz G

    2014-02-01

    Full Text Available Guillaume Schurtz,1,2 Cédric Delhaye,1 Christopher Hurt,1,2 Henri Thieuleux,1,2 Gilles Lemesle1–3 1Centre Hémodynamique et Unité des Soins Intensifs de Cardiologie, Hôpital Cardiologique, Centre Hospitalier Régional et Universitaire de Lille, Lille, France; 2Faculté de Médecine de Lille, Lille, France; 3Unité INSERM UMR744, Institut Pasteur de Lille, Lille, France Abstract: First-generation drug-eluting stents have raised concerns regarding the risk of late and very late stent thrombosis compared with bare metal stents and require prolonged dual antiplatelet therapy. Despite extensive investigations, the physiopathology of these late events remains incompletely understood. Aside from patient- and lesion-related risk factors, stent polymer has been cited as one of the potential causes. In fact, the persistence of durable polymer after complete drug release has been shown to be responsible for local hypersensitivity and inflammatory reactions. Third-generation drug-eluting stents with more biocompatible or biodegradable polymers have subsequently been developed to address this problem. In this article, we evaluate and discuss the concept and clinical results (safety and efficacy of a third-generation drug-eluting stent with biodegradable polymer: the Nobori® stent. Keywords: percutaneous coronary intervention, stent thrombosis, antiplatelet therapy

  4. The Use of Biodegradable Stents in Malignant Oesophageal Strictures for the Treatment of Dysphagia Before Neoadjuvant Treatment or Radical Radiotherapy: A Feasibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Krokidis, Miltiadis, E-mail: mkrokidis@hotmail.com; Burke, Chris; Spiliopoulos, Stavros; Gkoutzios, Panos [Guy' s and St. Thomas' NHS Trust, St Thomas' Hospital, Department of Radiology (United Kingdom); Hynes, Orla [Guy' s and St. Thomas' NHS Trust, Department of Surgery (United Kingdom); Ahmed, Irfan; Dourado, Renato; Sabharwal, Tarun [Guy' s and St. Thomas' NHS Trust, St Thomas' Hospital, Department of Radiology (United Kingdom); Mason, Robert [Guy' s and St. Thomas' NHS Trust, Department of Surgery (United Kingdom); Adam, Andreas [Guy' s and St. Thomas' NHS Trust, St Thomas' Hospital, Department of Radiology (United Kingdom)

    2013-08-01

    PurposeTo evaluate the clinical results of the use of biodegradable oesophageal stents in malignant strictures.MethodsEleven patients were included in this prospective analysis in which a woven polydioxanone biodegradable oesophageal stent was used. The inclusion criterion was that the patient underwent neoadjuvant treatment or radical radiotherapy after the stent insertion. Primary end points were dysphagia score at discharge, stent patency, and complication rate. Secondary end points were overall survival and surgical outcome of surgery.ResultsThere was a 100 % procedure technical success rate. Early complications occurred in three patients resulting in failure to restore oral nutrition. In the remaining eight patients, dysphagia was significantly improved at discharge. Mean stent patency rate in this group was 71.5 days. Stent dysfunction occurred in five of eight patients (62.5 %); in two of five patients this was due to local inflammatory reaction, and in three of five patients it was due to tumour growth after a mean time of 97.8 days, and a new metallic stent was consequently placed in four of five patients. One patient was successfully treated with esophagectomy. At the end of follow-up (mean time 102.1 days), three of eight stents were patent. The overall patient survival rate was 81.8 %.ConclusionAlthough short-term dysphagia scores improved, biodegradable stents do not appear to offer a clear beneficial effect in most cases of malignant strictures, particularly due to a local inflammatory reaction that may be induced. Technical improvement of the device and delineation of the patient group that would benefit from its use is necessary if further studies are to be conducted in the future.

  5. Local sustained delivery of acetylsalicylic acid via hybrid stent with biodegradable nanofibers reduces adhesion of blood cells and promotes reendothelialization of the denuded artery

    Directory of Open Access Journals (Sweden)

    Lee CH

    2014-01-01

    Full Text Available Cheng-Hung Lee,1,2 Yu-Huang Lin,3 Shang-Hung Chang,1 Chun-Der Tai,3 Shih-Jung Liu,2 Yen Chu,4 Chao-Jan Wang,5 Ming-Yi Hsu,5 Hung Chang,6 Gwo-Jyh Chang,7 Kuo-Chun Hung,1 Ming-Jer Hsieh,1 Fen-Chiung Lin,1 I-Chang Hsieh,1 Ming-Shien Wen,1 Yenlin Huang81Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Chang Gung University College of Medicine, Linkou, 2Department of Mechanical Engineering, 3Graduate Institute of Medical Mechatronics, Chang Gung University, 4Laboratory of Cardiovascular Physiology, Division of Thoracic and Cardiovascular Surgery, 5Department of Medical Imaging and Intervention, 6Hematology-Oncology Division, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, 7Graduate Institute of Clinical Medicinal Sciences, Chang Gung University College of Medicine, Linkou, 8Department of Anatomical Pathology, Chang Gung Memorial Hospital, Linkou, Tao-Yuan, TaiwanAbstract: Incomplete endothelialization, blood cell adhesion to vascular stents, and inflammation of arteries can result in acute stent thromboses. The systemic administration of acetylsalicylic acid decreases endothelial dysfunction, potentially reducing thrombus, enhancing vasodilatation, and inhibiting the progression of atherosclerosis; but, this is weakened by upper gastrointestinal bleeding. This study proposes a hybrid stent with biodegradable nanofibers, for the local, sustained delivery of acetylsalicylic acid to injured artery walls. Biodegradable nanofibers are prepared by first dissolving poly(D,L-lactide-co-glycolide and acetylsalicylic acid in 1,1,1,3,3,3-hexafluoro-2-propanol. The solution is then electrospun into nanofibrous tubes, which are then mounted onto commercially available bare-metal stents. In vitro release rates of pharmaceuticals from nanofibers are characterized using an elution method, and a high-performance liquid chromatography assay. The experimental results suggest that biodegradable nanofibers

  6. Fiber laser micromachining of magnesium alloy tubes for biocompatible and biodegradable cardiovascular stents

    Science.gov (United States)

    Demir, Ali Gökhan; Previtali, Barbara; Colombo, Daniele; Ge, Qiang; Vedani, Maurizio; Petrini, Lorenza; Wu, Wei; Biffi, Carlo Alberto

    2012-02-01

    Magnesium alloys constitute an attractive solution for cardiovascular stent applications due to their intrinsic properties of biocompatibility and relatively low corrosion resistance in human-body fluids, which results in as a less intrusive treatment. Laser micromachining is the conventional process used to cut the stent mesh, which plays the key role for the accurate reproduction of the mesh design and the surface quality of the produced stent that are important factors in ensuring the mechanical and corrosion resistance properties of such a kind of devices. Traditionally continuous or pulsed laser systems working in microsecond pulse regime are employed for stent manufacturing. Pulsed fiber lasers on the other hand, are a relatively new solution which could balance productivity and quality aspects with shorter ns pulse durations and pulse energies in the order of mJ. This work reports the study of laser micromachining and of AZ31 magnesium alloy for the manufacturing of cardiovascular stents with a novel mesh design. A pulsed active fiber laser system operating in nanosecond pulse regime was employed for the micromachining. Laser parameters were studied for tubular cutting on a common stent material, AISI 316L tubes with 2 mm in diameter and 0.2 mm in thickness and on AZ31 tubes with 2.5 mm in diameter and 0.2 in thickness. In both cases process parameters conditions were examined for reactive and inert gas cutting solutions and the final stent quality is compared.

  7. Early vascular healing with rapid breakdown biodegradable polymer sirolimus-eluting versus durable polymer everolimus-eluting stents assessed by optical coherence tomography

    Energy Technology Data Exchange (ETDEWEB)

    Tada, Tomohisa, E-mail: tomohisa@dhm.mhn.de [Deutsches Herzzentrum, Technische Universität, München (Germany); Byrne, Robert A. [Deutsches Herzzentrum, Technische Universität, München (Germany); Schuster, Tibor [Institut für Medizinische Statistik und Epidemiologie, München (Germany); Cuni, Rezarta [Deutsches Herzzentrum, Technische Universität, München (Germany); Kitabata, Hironori [Wakayama Medical University, Wakayama (Japan); Tiroch, Klaus [Deutsches Herzzentrum, Technische Universität, München (Germany); Dirninger, Alfred; Gratze, Franz; Kaspar, Klaus; Zenker, Gerald [Landeskrankenhaus Bruck/Mur (Austria); Joner, Michael; Schömig, Albert; Kastrati, Adnan [Deutsches Herzzentrum, Technische Universität, München (Germany)

    2013-03-15

    Background: Differences in early arterial healing patterns after stent implantation between biodegradable and durable polymer based new generation drug-eluting stents are not well understood. The aim of this study was to compare the healing patterns of a novel rapid breakdown (≤ 8 weeks) biodegradable polymer sirolimus-eluting stent (BP-SES) with a durable polymer everolimus-eluting stent (EES) using intravascular optical coherence tomography (OCT) at 4 months. Methods: A total of 20 patients were randomly assigned to stenting with BP-SES (n = 11) or EES (n = 9). Overall intravascular imaging was available for 15 (75%) patients. The primary endpoint was the difference in rate of uncovered struts between BP-SES and EES. To account for strut-level clustering, the results in both treatment groups were compared using a generalized linear mixed model approach. Results: Regarding the primary endpoint, BP-SES as compared to EES showed similar rates of uncovered struts (37 [6.8%] versus 167 [17.5%], odds ratio (OR) 0.45 (95% CI 0.09-2.24), p = 0.33). There were no malapposed struts in BP-SES group and 14 malapposed struts in EES group (p = 0.97). No difference in percent neointimal volume (14.1 ± 8.2% vs. 11.4 ± 6.4%, p = 0.56) was observed. Conclusions: Although rapid-breakdown BP-SES as compared to EES showed signs of improved early tissue coverage, after adjustment for strut-level clustering these differences were not statistically significant. No differences in ability to suppress neointimal hyperplasia after stent implantation between 2 stents were observed.

  8. Clinical outcomes of biodegradable polymer drug-eluting stents for percutaneous coronary intervention: an updated meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Kwong, Joey S W; Yu, Cheuk-Man

    2014-07-01

    Biodegradable polymer drug-eluting stents (DES) are innovative concepts in the era of percutaneous coronary intervention. We systematically reviewed the latest randomized evidence on the efficacy and safety of biodegradable polymer DES as compared to durable polymer DES. MEDLINE, Embase, and the Cochrane database were searched in August 2013 for eligible randomized controlled trials (RCTs) comparing biodegradable polymer DES with durable polymer DES. Clinical outcomes of interest were mortality, myocardial infarction (MI), target lesion revascularization (TLR), target vessel revascularization (TVR), and stent thrombosis. A total of 20 RCTs randomizing 20 021 participants were included, of whom 11 045 were allocated to biodegradable polymer DES and 8976 to durable polymer DES. Treatment of biodegradable polymer DES was not associated with a significant reduction of any of the clinical outcomes (all-cause mortality, odds ratio [OR]: 0.94, 95% confidence interval [CI]: 0.80 to 1.10, P = 0.42; cardiovascular mortality, OR: 0.97, 95% CI: 0.79 to 1.19, P = 0.74; MI, OR: 1.07, 95% CI: 0.91 to 1.26, P = 0.41; TLR, OR: 0.87, 95% CI: 0.69 to 1.08, P = 0.20; TVR, OR: 1.05, 95% CI: 0.85 to 1.28, P = 0.67; definite/probable stent thrombosis, OR: 0.80, 95% CI: 0.59 to 1.07, P = 0.14). Current randomized data indicate that clinical efficacy and safety profiles of biodegradable polymer DES are comparable to those of durable polymer DES. Findings from large-scale studies with rigorous methodology and long follow-up duration are needed.

  9. Urethral stricture

    Science.gov (United States)

    Urethral stricture may be caused by inflammation or scar tissue from surgery, disease, or injury. Rarely, it may be caused by pressure from a growing tumor near the urethra. Other factors that increase the risk for this condition include: Sexually transmitted ...

  10. Biodegradable intestinal stents:A review

    Institute of Scientific and Technical Information of China (English)

    Zhanhui Wang; Nan Li; Rui Li; Yawei Li; Liqun Ruan

    2014-01-01

    Biodegradable stents are an attractive alternative to self-expanding metal stents in the treatment of intestinal strictures. Biodegradable stent can be made of biodegradable polymers and biodegradable metals (magnesium alloys). An overview on current biodegradable intestinal stents is presented. The future trends and perspectives in the development of biodegradable intestinal stents are proposed. For the biodegradable polymer intestinal stents, the clinical trials have shown promising results, although improved design of stents and reduced migration rate are expected. For the biodegradable magnesium intestinal stents, results of preliminary studies indicate magnesium alloys to have good biocompatibility. With many of the key fundamental and practical issues resolved and better methods for adjusting corrosion resistance and progressing biocompatibilities of magnesium alloys, it is possible to use biodegradable intestinal stents made of magnesium alloys in hospital in the not too distant future.

  11. Effect of biolimus-eluting stents with biodegradable polymer vs bare-metal stents on cardiovascular events among patients with acute myocardial infarction

    DEFF Research Database (Denmark)

    Räber, Lorenz; Kelbæk, Henning; Ostojic, Miodrag

    2012-01-01

    The efficacy and safety of drug-eluting stents compared with bare-metal stents remains controversial in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).......The efficacy and safety of drug-eluting stents compared with bare-metal stents remains controversial in patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI)....

  12. Long-Term Efficacy and Safety of Biodegradable-Polymer Biolimus-Eluting Stents

    DEFF Research Database (Denmark)

    Kaiser, Christoph; Galatius, Søren; Jeger, Raban

    2015-01-01

    risk difference, 0.78%; -1.93% to 3.50%; P for noninferiority 0.042; per protocol P=0.09) and superior to BMS (absolute risk difference, -5.16; -8.32 to -2.01; P=0.0011). The 3 stent groups did not differ in the combined safety end point, with no decrease in events >1 year, particularly VLST with BP......-DES. CONCLUSIONS: In large vessel stenting, BP-DES appeared barely noninferior compared with DP-DES and more effective than thin-strut BMS, but without evidence for better safety nor lower VLST rates >1 year. Findings challenge the concept that durable polymers are key in VLST formation. CLINICAL TRIAL...

  13. Long-term effects of biodegradable versus durable polymer-coated sirolimus-eluting stents on coronary arterial wall morphology assessed by virtual histology intravascular ultrasound

    Institute of Scientific and Technical Information of China (English)

    LIU Hui-liang; ZHANG Jiao; JIN Zhi-geng; LUO Jian-ping; MA Dong-xing; YANG Sheng-li; LIU Ying; HAN Wei; JING Li-min; MENG Rong-ying

    2011-01-01

    Background The durable presence of polymer coating on drug-eluting stent (DES) surface may be one of the principal reasons for stent thrombosis. The long-term coronary arterial response to biodegradable polymer-coated sirolimus-eluting stent (BSES) in vivo remained unclear.Methods Forty-one patients were enrolled in this study and virtual histology intravascular ultrasound (VH-IVUS) was performed to assess the native artery vascular responses to BSES compared with durable polymer-coated SES (DSES) during long-term follow-up (median: 8 months). The incidence of necrotic core abutting to the lumen was evaluated at follow-up.Results With similar in-stent late luminal loss (0.15 mm (0.06-0.30 mm) vs. 0.19 mm (0.03-0.30 mm), P=0.772), the overall incidence of necrotic core abutting to the lumen was significantly less in BSES group than in DSES group (44% vs.63%, P <0.05) (proximal 18%, stented site 14% and distal 12% in BSES group, proximal 19%, stented site 28% and distal 16% in DSES group). The DSES-treated segments had a significant higher incidence of necrotic core abutting to the lumen through the stent struts (73% vs. 36%, P <0.01). In addition, more multiple necrotic core abutting to the lumen was observed in DSES group (overall: 63% vs. 36%, P <0.05). Furthermore, when the stented segments with necrotic core abutting to the lumen had been taken into account only, DSES-treated lesions tended to contain more multiple necrotic core abutting to the lumen through the stent struts than BSES-treated lesions (74% vs. 33%), although there was no statistically significant difference between them (P=0.06).Conclusions By VH-IVUS analysis at follow-up, a greater frequency of stable lesion morphometry was shown in lesions treated with BSESs compared with lesions treated with DSESs. The major reason was BSES produced less toxicity to the arterial wall and facilitated neointimal healing as a result of polymer coating on DES surface biodegraded as time went by.

  14. Clinical Outcomes from Unselected “Real-World” Patients with Long Coronary Lesion Receiving 40 mm Biodegradable Polymer Coated Sirolimus-Eluting Stent

    Directory of Open Access Journals (Sweden)

    Anurag Polavarapu

    2015-01-01

    Full Text Available Background. Long lesions being implanted with drug-eluting stents (DES are associated with relatively high restenosis rates and higher incidences of adverse events. Objectives. We aimed to examine the safety and efficacy of the long (40 mm biodegradable polymer coated Indolimus sirolimus-eluting stent (SES in real-world patients with long coronary lesions. Methods. This study was observational, nonrandomized, retrospective, and carried out in real-world patients. A total of 258 patients were enrolled for the treatment of long coronary lesions, with 40 mm Indolimus. The primary endpoints in the study were incidence of major adverse cardiac events (MACE, a miscellany of cardiac death, myocardial infarction (MI, target lesion revascularization (TLR or target vessel revascularization (TVR, and stent thrombosis (ST up to 6-month follow-up. Results. The study population included higher proportion of males (74.4% and average age was 53.2 ± 11.0 years. A total of 278 lesions were intervened successfully with 280 stents. The observed MACE at 6-month follow-up was 2.0%, which included 0.8% cardiac death and 1.2% MI. There were no TLR or TVR and ST observed during 6-month follow-up. Conclusions. The long (40 mm Indolimus stent demonstrated low MACE rate and was proven to be safe and effective treatment for long lesions in “real-world” patients.

  15. First report of a novel abluminal groove filled biodegradable polymer rapamycin-eluting stent in de novo coronary artery disease: results of the first in man FIREHAWK trial

    Institute of Scientific and Technical Information of China (English)

    QIAN Jie; Gary S.Mintz; Martin B.Leon; GAO Run-lin; XU Bo; Alexandra J.Lansky; YANG Yue-jin; QIAO Shu-bin; WU Yong-jian; CHEN Jue; HU Feng-huan; YANG Wei-xian

    2012-01-01

    Background Durable polymers used for first-generation drug-eluting stents (DES) potentially contribute to persistent inflammation and late DES thrombosis.We report the first in human experience with the rapamycin-eluting biodegradable polymer coated cobalt-chromium FIREHAWK stent with abluminal groove.Methods A total of 21 patients with stable or unstable angina,or prior myocardial infarction,with single de novo native coronary stenoses <30 mm in length in vessel sizes ranging from 2.25 to 4.0 mm were enrolled.The primary endpoint was major adverse cardiac events (MACE) at 30 days defined as the composite of cardiac death,myocardial infarction (Q and non-Q),or ischemia-driven target lesion revascularization.Secondary endpoints include device,lesion,and clinical success rates,4-month in-stent late lumen loss by quantitative coronary angiography (QCA),proportion of uncovered or malapposed stent struts by optical coherence tomograpphy (OCT) at 4 months,and MACE at 4,12,24 and 36-month follow-up.Results Device success was 95.7%,lesion and clinical success was 100.0%.There were no MACE events at 30 days.One patient died of non-cardiac hemorrhagic stroke 5 days after index procedure.At 4 months,in-stent late loss was (0.13±0.18) mm,and complete strut coverage was 96.2% by OCT with 0.1% strut malapposition.At 4-month follow-up there was no additional MACE events,and a single target vessel (non-target lesion) revascularization.Conclusions The FIREHAWK abluminal groove biodegradable polymer rapamycin-eluting stent demonstrated feasibility,safety and efficacy in this first in human experience.OCT findings indicated excellent stent strut coverage 4months after implantation.Larger studies are required to confirm whether the early FIREHAWK stent results translate into longer term restenosis and thrombosis benefits.

  16. 2-year outcome after biodegradable polymer sirolimus- and biolimus- eluting coronary stents.From the randomized SORT OUT VII trial

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Maeng, Michael; Raungaard, Bent

    2017-01-01

    : The 2-year pre-specified endpoint target lesion failure did not differ significantly between the sirolimus-eluting stent: 6.7% and the biolimus-eluting stent: 7.0% (rate ratio (RR) 0.94, 95% confidence interval (CI) 0.70-1.28). Definite stent thrombosis were numerically lower in the sirolimus...

  17. First-in-man randomized comparison of BuMA Supreme biodegradable polymer sirolimus-eluting versus durable polymer zotarolimus-eluting coronary stents: The PIONEER trial.

    Science.gov (United States)

    von Birgelen, Clemens; Asano, Taku; Amoroso, Giovanni; Aminian, Adel; Brugaletta, Salvatore; Vrolix, Mathias; Hernandez-Antolín, Rosana; van de Harst, Pim; Iñiguez, Andres; Janssens, Luc; Smits, Pieter C; Wykrzykowska, Joanna J; Ribeiro, Vasco Gama; Periera, Helder; Canas da Silva, Pedro; Piek, Jan J; Onuma, Yoshinobu; Serruys, Patrick W; Sabaté, Manel

    2017-09-19

    A second iteration of a sirolimus-eluting stent (SES) that has a biodegradable PLGA-polymer coating with electrografting base layer on a thin-strut (80µm) cobalt-chromium platform (BuMA Supreme; SINOMED, Tianjin, China) has been developed. This first-in-man trial assessed the efficacy and safety of the novel device. This randomized, multi-center, single-blinded, non-inferiority trial compared BuMA Supreme SES versus contemporary durable polymer zotarolimus-eluting stents (ZES) in terms of angiographic in-stent late lumen loss (LLL) at 9-months follow-up as the primary endpoint. A total of 170 patients were randomly allocated to treatment with SES (n=83) or ZES (n=87). At 9-month angiographic follow-up, in-stent LLL was 0.29±0.33mm in SES and 0.14±0.37mm in ZES (Pnon-inferiority=0.45). The in-stent percent diameter stenosis and the binary restenosis rate of the two treatment arms were similar (19.2±12.0% vs. 16.1±12.6%, p=0.09, and 3.3% vs. 4.4%, P=1.00, respectively). At 12-month clinical follow-up, there was no difference between treatment arms with regard to a device-oriented composite clinical endpoint (4.9% vs. 5.7%; p=0.72). The PIONEER trial did not meet its primary endpoint in terms of in-stent LLL at 9-month follow-up. However, this result did not translate into any increase in restenosis rate or impairment in 12-month clinical outcomes.

  18. Gender difference on five-year outcomes of EXCEL biodegradable polymer-coated sirolimus-eluting stents implantation: results from the CREATE study

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei; QIAO Bing; HAN Ya-ling; LI Yi; XU Kai; ZHANG Quan-yu; YANG Li-xia

    2013-01-01

    Background The gender difference on long-term outcome in unselected patients after percutaneous coronary intervention (PCI) has not yet been fully investigated.This study aimed to evaluate the gender difference on five-year outcomes following EXCEL biodegradable polymer-coated sirolimus-eluting stenting in patients with coronary disease.Methods A total of 2077 "all comers",consisting of 1528 (73.6%) men and 549 (26.4%) women,who were exclusively treated with EXCEL coronary stents were enrolled in the prospective CREATE study at 59 centers from four countries.After propensity score matching,the baseline characteristics of the two groups were well matched.Recommended antiplatelet regimen was clopidogrel and aspirin for six months followed by chronic aspirin therapy.The primary outcome that was the rate of major adverse cardiac events (MACE),defined as a composite of cardiac mortality,non-fatal myocardial infarction (MI) and target lesion revascularization (TLR),and stent thrombosis (ST) at five years were compared between the two gender groups.Results In the two groups,women had higher proportions of clinical risk factors,such as being elderly,diabetes mellitus,hypertension and hyperlipidemia,compared to men.Besides,the mean target vessel number per patient was higher and the mean reference vessel diameter smaller for women.Men had higher risks of cardiac death (3.7% vs.1.6%,P=0.021) and MACE (8.4% vs.4.7%,P=0.004) at five years compared with women.However,the cumulative hazards of non-fatal MI and TLR were similar between men and women.The incidence of Academic Research Consortium (ARC) definite or probable stent thrombosis was similar between the two groups (1.3% vs.1.0%,P=0.639).Prolonged clopidogrel therapy (>6 months) did not reduce the cumulative hazards of ST from six months to five years in both men (x2=0.098,log rank P=0.754) and women (x2=2.043,log rank P=0.153) patients.Conclusions Women had a lower MACE and cardiac death rate than men

  19. Favorable Outcomes after Implantation of Biodegradable Polymer Coated Sirolimus-Eluting Stents in Diabetic Population: Results from INDOLIMUS-G Diabetic Registry

    Directory of Open Access Journals (Sweden)

    Anurag Polavarapu

    2015-01-01

    Full Text Available Objective. The main aim is to evaluate safety, efficacy, and clinical performance of the Indolimus (Sahajanand Medical Technologies Pvt. Ltd., Surat, India sirolimus-eluting stent in high-risk diabetic population with complex lesions. Methods. It was a multicentre, retrospective, non-randomized, single-arm study, which enrolled 372 diabetic patients treated with Indolimus. The primary endpoint of the study was major adverse cardiac events (MACE, which is a composite of cardiac death, target lesion revascularization (TLR, target vessel revascularization (TVR, myocardial infarction (MI, and stent thrombosis (ST. The clinical follow-ups were scheduled at 30 days, 6 months, and 9 months. Results. The mean age of the enrolled patients was 53.4 ± 10.2 years. A total of 437 lesions were intervened successfully with 483 stents (1.1 ± 0.3 per lesion. There were 256 (68.8% male patients. Hypertension and totally occluded lesions were found in 202 (54.3% and 45 (10.3% patients, respectively. The incidence of MACE at 30 days, 6 months and 9 months was 0 (0%, 6 (1.6%, and 8 (2.2%, respectively. The event-free survival at 9-month follow-up by Kaplan Meier method was found to be 97.8%. Conclusion. The use of biodegradable polymer coated sirolimus-eluting stent is associated with favorable outcomes. The results demonstrated in our study depict its safety and efficacy in diabetic population.

  20. Impact of biodegradable versus durable polymer drug-eluting stents on clinical outcomes in patients with coronary artery disease: a meta-analysis of 15 randomized trials

    Institute of Scientific and Technical Information of China (English)

    Zhang Yaojun; Tian Nailiang; Dong Shengjie; Ye Fei; Li Minghui; Christos V.Bourantas; Javaid Iqbal

    2014-01-01

    Background Drug eluting stents (DESs) made with biodegradable polymer have been developed in an attempt to improve clinical outcomes.However,the impact of biodegradable polymers on clinical events and stent thrombosis (ST) remains controversial.Methods We searched Medline,the Cochrane Library and other internet sources,without language or date restrictions for articles comparing clinical outcomes between biodegradable polymer DES and durable polymer DES.Safety endpoints were ST (definite,definite/probable),mortality,and myocardial infarction (MI).Efficacy endpoints were major adverse cardiac event (MACE) and target lesion revascularization (TLR).Results We identified 15 randomized controlled trials (n=17 068) with a weighted mean follow-up of 20.6 months.There was no statistical difference in the incidence of definite/probable ST between durable polymer-and biodegradable polymerDES; relative risk (RR) 0.83; 95% confidence interval (CI) 0.62-1.11; P=0.22.Biodegradable polymer DES had similar rates of definite ST (RR 0.94,95% CI 0.66-1.33,P=0.72),mortality (RR 0.94,95% C/0.82-1.09,P=0.43),MI (RR 1.08,95% CI 0.92-1.26.P=0.35),MACE (RR 0.99,95% CI 0.91-1.09,P=0.85),and TLR (RR,0.94,95% CI 0.83-1.06,P=0.30) compared with durable polymer DES.Based on the stratified analysis of the included trials,the treatment effect on definite ST was different at different follow-up times:≤1 year favoring durable polymer DES and >1 year favoring biodegradable polymer DES.Conclusions Biodegradable polymer DES has similar safety and efficacy for treating patients with coronary artery disease compared with durable polymer DES.Further data with longer term follow-up are warranted to confirm the potential benefits of biodegradable polymer DES.

  1. A prospective multicenter parallel-controlled trial of TIVOLI biodegradable-polymer-based sirolimus-eluting stent compared to ENDEAVOR zotarolimus-eluting stent for the treatment of coronary artery disease: 8-month angiographic and 2-year clinical follow-up results

    Institute of Scientific and Technical Information of China (English)

    XU Bo; LI Wei-min; CHEN Ji-yan; WANG Lei; WANG Yong; GE Jun-bo; LI Wei; GAO Run-lin; DOU Ke-fei; HAN Ya-ling; L(U) Shu-zheng; YANG Yue-jin; HUO Yong; WANG Le-feng; CHEN Yun-dai; WANG Hai-chang

    2011-01-01

    Background Available drug-eluting stents (DES) have achieved great success in reducing restenosis rates. Recently,investigators have demonstrated that the durable polymer carrier plays a significant role in DES-related hypersensitive reaction and delays vessel healing. TIVOLI stent is a novel sirolimus-eluting coronary stent with biodegradable coating containing sirolimus and polylactic-co-glycolic acid (PLGA) polymer. The present study sought to evaluate the effectiveness and safety of the TIVOLI biodegradable-polymer-based sirolimus-eluting stent in treating patients with coronary artery disease.Methods A prospective, multicenter clinical trial comparing TIVOLI biodegradable coated sirolimus-eluting stent with ENDEAVOR zotarolimus-eluting stent was conducted in 324 patients (TIVOLI group: 168 patients; ENDEAVOR group:156 patients) at 12 centers in China to demonstrate the non-inferiority of in-stent late loss with TIVOLI stent compared to ENDEAVOR stent in subjects with a maximum of two de novo native coronary artery lesions (lesion length ≤40 mm,reference vessel diameter 2.25-4.00 mm). The primary end point was angiographic in-stent late loss at 8-month. The secondary end points were clinical outcomes at 2 years,including major adverse cardiac events (cardiac death,myocardial infarction, or target-lesion revascularization) and stent thrombosis.Results Angiographic late lumen loss at 8 months in the TIVOLI group was superior to the ENDEAVOR group (in-stent (0.25±0.33) mm vs. (0.57±0.55) mm, diff (95% CI)-0.23 (-0.32, -0.14), P <0.0001; in-segment (0.25±-0.33) mm vs. (0.42±-0.55) mm, diff (95% CI) -0.13 (-0.23, -0.02),P=0.0083). The rate of in-stent binary restenosis at 8 months was reduced from 8.6% in the ENDEAVOR group to 2.9% in the TIVOLI group (P=0.0229). Compared to ENDEAVOR stent, TIVOLI stent resulted in a significant reduction in target-lesion revascularization (4.2% vs. 9.6%, P=0.0495) at 2 years. The two-year major adverse cardiac events (MACE

  2. 可降解镁合金管材及其胆管内支架%Biodegradable Magnesium Alloy Tubes and Biliary Stent

    Institute of Scientific and Technical Information of China (English)

    皇甫强; 袁思波; 于振涛; 韩建业; 程军; 张亚峰; 余森

    2015-01-01

    Because of the biodegradable character, magnesium alloys opened a new era applications of biliary stent. AZ31 magnesium alloy rolled in room temperature, if the ε value was controlled at 15%, it could get the best tube surface and mechanical capability, the excellent heat treatment was 400 ℃. These techniques can slake the internal stress and crystal grain could be refinement. Compared the biocompatibility and axial shortening rate between magnesium alloy stent and stainless steel stent, the feasibility of biodegradable stent in the bile duct field was considered.%镁合金支架由于其具有独特的可降解性,开启了胆管支架应用的新纪元。本文对AZ31管材进行了不同变形量的冷轧试验,控制变形量ε在15%左右,可得到最佳的表面质量及管材性能,选择400℃的热处理工艺能有效消除内应力,同时细化晶粒、均匀组织。文章还对镁合金胆管支架和临床广泛在用的不锈钢支架在生物相容性、支架扩张性、轴向缩短率等方面进行了对比,考量可降解支架在胆管领域应用的可行性。

  3. A randomized, open-label clinical trial using optical coherence tomography to compare two sirolimus-eluting stents, one with a biodegradable polymer and the other with a permanent polymer.

    Science.gov (United States)

    Tian, Feng; Chen, Yundai; Liu, Changfu; Jin, Qinhua; Chen, Lian; Sun, Zhijun; Liu, Hongbin; Guo, Jun; Gai, Luyue

    2013-04-01

    Intimal hyperplasia appears to differ after implanting a drug-eluting stent (DES) with a biodegradable or a permanent polymer. The aim of the present study was to compare biodegradable with permanent polymer DES, since the available data are limited. One hundred patients with de novo coronary artery stenosis were included in this study. The patients were classified into 2 groups: DES with a biodegradable polymer (n=50) and DES with a permanent polymer (n=50). Optical coherence tomography (OCT) examination was performed before and after stent implantation. A follow‑up OCT, performed 1 year after stent implantation, compared the morphologies of intimal hyperplasia in the 2 groups. The frequencies of uncovered stent struts (2.27 vs. 1.87%, P=0.145) and stent strut malapposition (1.9 vs. 2.02%, P=0.655) upon the first-year follow-up were not significantly different. Average neointimal thickness was lower in the biodegradable compared with the permanent polymer group (106.12±80.65 vs. 181.20±146.96 µm, Pbiodegradable compared with the permanent polymer group (62.1 vs. 35.9%, Pbiodegradable compared with the permanent polymer group (57.7±24.6 vs. 67.6±22.4 µm, Pbiodegradable polymer DES resulted in significantly lower intimal hyperplasia and had well-proportioned intimal coverage compared with permanent polymer DES.

  4. The Design Research on a New Novel Biodegradable Esophageal Stents%新型可降解食管支架的设计研究

    Institute of Scientific and Technical Information of China (English)

    高小龙; 冷德嵘; 刘春俊; 胡洁; 张岚; 李常青; 唐志; 沈正华

    2016-01-01

    目前,良性食管狭窄的发病比例越来越高,对于复杂性食管良性狭窄的治疗方式主要为内镜下治疗支架置入。金属支架植入后由于粘膜增生,导致二次手术时支架不易回收,增加了病人的痛苦,而可降解支架在人体管腔内完成治疗使命后,支架不断降解,最终在体内降解消失,避免了长期异物影响带来的并发症,以及再取出支架的痛苦。本文通过比较目前不同可降解材料制备的可降解非血管支架的研究进展,如PLA、PLLA、PGA、PLGA、PDO等可降解支架,选用PDO作为可降解支架编织材料,同时设计了几种不同结构的支架,通过对比支架各方面的性能,发现分段式可降解支架,具有良好的支撑性能,且易于装载入输送装置;进一步通过动物实验研究发现,P D O丝材编织的分段式可降解支架,可以在动物体内以较高的力学性能持续维持6周,而不发生移位、结构破坏;8周以后,支架崩解,随后消失,而相应的粘膜增生恢复;因此,初步确认上述可降解支架在动物体内是安全的、有效的,具有良好的临床应用价值与市场前景。在此基础上,进一步对研究过程中发现的可降解支架的问题,以及改进方向做了相关阐述。%At present, the incidence rate of benign esophageal stenosis has become more and more high. And the stent implantation under endoscopic has become the main treatment method for the complexity of benign esophageal stenosis. Unfortunately, due to the mucosal hyperplasia after Stent implantation, the stents is not easy to recover, and increase the pain of patients. However, the biodegradable stents continue to degrade until they ifnaly disappear when the treatment mission is complete in the human lumen. It avoids the complications caused by long-term foreign body effects, as wel as the pain of removing the stent. This article through the comparison of

  5. 复合材料气管内可降解支架的降解性能*☆%Degradable properties of biodegradable composite stents in the trachea

    Institute of Scientific and Technical Information of China (English)

    马永富; 刘阳; 郭俊唐; 张涛; 梁朝阳

    2013-01-01

      背景:经过对目前国内外可降解材料支架研究的充分调研,以及在镍钛记忆合金支架设计、制作、实验和临床应用的经验基础上,提出一种新型自膨式左旋聚乳酸可降解覆膜气管内支架的研究。目的:自行制作左旋聚乳酸复合羟基磷灰石生物可降解材料气管内支架,测试其机械力学、生物相容性及降解性能。方法:利用计算机辅助设计支架模型,应用相对分子质量150000的左旋聚乳酸和羟基磷灰石按一定比例混合后研制直径分别为20,21,22,23,24,25,26 mm的可降解气管内支架,采用万能实验机检测其力学性能。将研制的可降解气管内支架以合适的尺寸置入杂种犬气管狭窄模型,置入后4,8,12,16周观察支架黏均分子质量及质量变化,同时检测可降解气管内支架体外降解黏均分子质量及质量的变化。结果与结论:复合材料可降解气管内支架的平均径向支撑力为7.8 kPa,支架表面覆盖率小于20%,支架扩张率≥4%,支架纵向缩短率≤9%,已达到气管内可降解支架的力学要求。支架置入后4-16周组织病理学观察未见明显炎症反应。支架体内降解解组不同时间点的黏均分质量下降程度及质量损失率高于体外降解组(P均<0.05)。表明左旋聚乳酸/羟基磷灰石复合材料支架具有良好力学性能、生物相容性及可降解性。%BACKGROUND:Through a ful investigation of biodegradable scaffolds, we propose a new self-expanding degradable poly-L-lactide coated endotracheal stent based on the design, production, experimental and clinical applications of nickel titanium memory alloy stent. OBJECTIVE:To design a kind of biodegradable endotracheal stent with poly-L-lactide and hydroxyapatite, and to test its mechanical properties, biocompatibility and biodegradation capacity. METHODS:With the technology of computer aided design, the stents were

  6. Stages of Urethral Cancer

    Science.gov (United States)

    ... Cancer Treatment Urethral Cancer Treatment (PDQ®)–Patient Version General Information About Urethral Cancer Go to Health Professional ... In men, the urethra also carries semen . Enlarge Anatomy of the male urinary system (left panel) and ...

  7. 携带缓释药物的生物可降解输尿管支架体内外降解特性研究%Biodegradation characteristics of a new kind of drug-eluting biodegradable ureteral stent in vivo and in vitro

    Institute of Scientific and Technical Information of China (English)

    符伟军; 张旭; 曹磊; 徐福强; 李钢; 王忠新; 洪宝发; 王晓雄; 胡堃; 崔福斋

    2010-01-01

    目的 观察携带缓释药物的生物可降解输尿管支架的体内外降解特性,比较输尿管裸支架与输尿管药物支架的生物相容性等差异.方法 将输尿管裸支架与输尿管药物支架分别浸泡于新鲜人体尿液中,观察体外支架降解.将两种输尿管支架分别包埋于18只Wistar大鼠脊柱两侧肌肉内.通过组织切片染色、扫描电镜、相对分子质量测定及质量变化分析体内生物可降解特性差异.结果 输尿管药物支架体外人体尿液浸泡10周时,支架失重率已达35%.切片染色发现组织反应较轻,纤维增生不明显.扫描电镜支架表面失去原有形态,出现大块状脱落物.12周时,降解为细小泥沙样颗粒输尿管裸支架组纤维膜厚(21.24±3.27)μm,输尿管药物支架组纤维膜厚(10.75±3.69)μm,两组比较差异有统计学意义(P<0.01).结论 与输尿管裸支架比较,输尿管药物支架的降解特性相似,但炎症反应轻,包裹纤维膜厚度更薄,具有良好的组织相容性.%Objective To observe the degradation characteristics of the novel drug-eluting biodegradable polylactide ureteral stents in vivo and in vitro, and to compare biocompatibility differences of the pure biodegradable ureteral stents with paclitaxel-eluting biodegradable ureteral stent. Methods The polylactide ureteral stents were dipped into fresh urine specimen and urinary environment simulated in vivo by shocks. And in vivo these two kinds of ureteral stents were implanted in the dorsal muscle of 16 Wistar rats. Histological study was used to investigate the tissue reaction of the material and the differeces of these two kind of ureteral stents were evaluated. Scanning election microscopy (SEM) and measurement of gravity and molecular weight were performed to make out the biodegradation characteristics of stents in vitro and in vivo. Results After being soaked in human urine for 10 weeks, weight of the novel drug-eluting stents was decreased by 35

  8. The qualitative assessment of biodegradable coronary stents with the use of intravascular ultrasound, optical coherence tomography and histology

    OpenAIRE

    Burcu GÜL

    2014-01-01

    Percutaneous coronary intervention (PCI) is the most common treatment for coronary artery disease (CAD). The first form of PCI introduced was balloon angioplasty. After that, the advent of coronary stents (tubular wire mesh for intravascular mechanical support) led to a new era in interventional cardiology. Through the implantation of bare metal stents (BMS), all three limitations of balloon angioplasty – coronary artery dissection, elastic recoil and negative remodelling – are prevented. Unf...

  9. Comparison of paclitaxal vs.sirolimus eluting stents with bio-degradable polymer for the treatment of coronary bifurcation lesions: subgroup analysis from DKCRUSH-I and DKCRUSH-Ⅱ studies

    Institute of Scientific and Technical Information of China (English)

    CHEN Shao-liang; ZHOU Yong; DING Shi-qin; Tak W Kwan; Gary Mintz; Teguh Santoso; ZHANG Jun-jie; YE Fei; XU Ya-wei; FU Qiang; KAN Jing; Chitprapai Paiboon

    2012-01-01

    Background The difference in clinical outcome between paclitaxal-eluting stents (PES) and sirolimus-eluting stents with bio-degradable polymer (SES-BDP) for bifurcation lesions remains unclear.The present study aimed to investigate the one-year clinical outcome after DK crush stenting using PES (TaxusTM) vs.SES-BDP (ExcelrM) from our database.Methods A total of 275 patients (90 from the DKCRUSH-I and 185 from the DKCRUSH-Ⅱ study) were studied.The primary endpoint was the occurrence of major adverse cardiac events (MACE) at 12 months; including cardiac death,myocardial infarction (MI),or target vessel revascularization (TVR).The rate of binary restenosis and stent thrombosis served as secondary endpoints.Results At follow-up,minimal luminal diameter (MLD) in the Taxus group was (2.11±0.66) mm,with resultant increased target lesion revascularization (TLR) 12.2% and TVR 14.4%,significantly different from the Excel group; (2.47±0.56) mm,P <0.001,3.2%,P=0.006,4.9%,P=0.019,respectively.As a result there was a significant difference in MACE between the Taxus (20.0%) and Excel (10.3%,P=0.038) groups.Overall stent thrombosis was monitored in 11 patients (4.0%),with five in the Excel group (2.7%) and six in the Taxus group (6.7%).All stent thrombosis in the Excel group was classified as early,and all were defined as late in the Taxus group.Conclusion The Excel stent had lower rate of stent thrombosis,TLR,TVR,and composite MACE at 12-month after an indexed stenting procedure,compared to the Taxus stent.

  10. Drug-eluting stents with biodegradable polymer for the treatment of patients with diabetes mellitus: clinical outcome at 2 years in a large population of patients

    Directory of Open Access Journals (Sweden)

    Wiemer M

    2015-02-01

    Full Text Available Marcus Wiemer,1 Gian Battista Danzi,2 Nick West,3 Vassilios Voudris,4 René Koning,5 Stefan Hoffmann,6 Mario Lombardi,7 Josepa Mauri,8 Rade Babic,9 Fraser Witherow10On behalf of the NOBORI 2 Investigators 1Department of Cardiology, Heart and Diabetes Center North Rhine–Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany; 2Ospedale Maggiore Policlinico, Milan, Italy; 3Papworth Hospital, Cambridge, UK; 4Onassis Cardiac Surgery Center, Athens, Greece; 5Clinique Saint Hilaire, Rouen, France; 6Vivantes Netzwerk für Gesundheit GmbH, Berlin, Germany; 7Azienda Ospedaliera Villa Sofia, Palermo, Italy; 8Hospital Universitari Germans Trias i Pujol, Badalona, Spain; 9Institute for Cardiovascular Diseases Dedinje, Belgrade, Serbia; 10Dorset County Hospital, Dorchester, UK Objective: This study investigates the safety and efficacy of a third-generation drug-eluting stent (DES with biodegradable polymer in the complex patient population of diabetes mellitus (DM. Clinical trial registration: ISRCTN81649913. Background: Percutaneous coronary interventions in patients with DM are associated with a higher incidence of death, restenosis, and stent thrombosis as compared to non-diabetic patients. The use of a DES has been shown to improve outcomes in diabetic patients. Methods: Out of 3,067 patients, enrolled in 126 centers worldwide in the NOBORI 2 registry, 888 patients suffered from DM, 213 of them (14% being insulin-dependent DM (IDDM. Two years’ follow-up has been completed in this study. Results: At 1- and 2-year follow-up, 97% and 95% of the patients, respectively, were available. The reported target lesion failure (TLF rates at 1- and 2-year follow-up were 6.0% and 7.2% in the DM group, respectively, and 3.0% and 4.2% in the non-DM group, respectively (P<0.001 for both years. Inside the DM group, the TLF rates of 9.9% and 11.7% at the 1- and 2-year follow-ups, respectively, in patients with IDDM were significantly higher than the TLF rates of 4

  11. Treatment Options for Urethral Cancer

    Science.gov (United States)

    ... Treatment Health Professional Urethral Cancer Treatment Urethral Cancer Treatment (PDQ®)–Patient Version General Information About Urethral Cancer ... Certain factors affect prognosis (chance of recovery) and treatment options. The prognosis (chance of recovery ) and treatment ...

  12. A Giant Urethral Calculus.

    Science.gov (United States)

    Sigdel, G; Agarwal, A; Keshaw, B W

    2014-01-01

    Urethral calculi are rare forms of urolithiasis. Majority of the calculi are migratory from urinary bladder or upper urinary tract. Primary urethral calculi usually occur in presence of urethral stricture or diverticulum. In this article we report a case of a giant posterior urethral calculus measuring 7x3x2 cm in a 47 years old male. Patient presented with acute retention of urine which was preceded by burning micturition and dribbling of urine for one week. The calculus was pushed in to the bladder through the cystoscope and was removed by suprapubic cystolithotomy.

  13. Blocked Urethral Valves

    Science.gov (United States)

    ... Blocked Urethral Valves Health Issues Listen Español Text Size Email Print Share Blocked Urethral Valves Page Content Article Body Urine leaves the bladder through a tube called the urethra, which in boys passes through the penis. Rarely, small membranes form across the urethra in ...

  14. Drug-eluting stents to prevent stent thrombosis and restenosis.

    Science.gov (United States)

    Im, Eui; Hong, Myeong-Ki

    2016-01-01

    Although first-generation drug-eluting stents (DES) have significantly reduced the risk of in-stent restenosis, they have also increased the long-term risk of stent thrombosis. This safety concern directly triggered the development of new generation DES, with innovations in stent platforms, polymers, and anti-proliferative drugs. Stent platform materials have evolved from stainless steel to cobalt or platinum-chromium alloys with an improved strut design. Drug-carrying polymers have become biocompatible or biodegradable and even polymer-free DES were introduced. New limus-family drugs (such as everolimus, zotarolimus or biolimus) were adopted to enhance stent performances. As a result, these new DES demonstrated superior vascular healing responses on intracoronary imaging studies and lower stent thrombotic events in actual patients. Recently, fully-bioresorbable stents (scaffolds) have been introduced, and expanding their applications. In this article, the important concepts and clinical results of new generation DES and bioresorbable scaffolds are described.

  15. Five-year outcomes of chronic total occlusion treatment with a biolimus A9-eluting biodegradable polymer stent versus a sirolimus-eluting permanent polymer stent in the LEADERS all-comers trial

    NARCIS (Netherlands)

    M. Ghione (Matteo); J.J. Wykrzykowska (Joanna); S. Windecker (Stephan); P.W.J.C. Serruys (Patrick); P.E. Buszman (Pawel); A. Linke (Axel); H.Y. Sohn (Hae Y); R. Corti (Roberto); M.L. Antoni (Louisa); W. Wijns (William); Estevez-Loureiro, R. (Rodrigo); M-C. Morice (Marie-Claude); G.A. van Es (Gerrit Anne); R.J.M. van Geuns (Robert Jan); P. Jùni (Peter); P. Eerdmans (Pedro); T. de Vries (Ton); Konik, S. (Stéphanie); C. di Mario (Carlo)

    2016-01-01

    textabstractBackground: Few data are available on long-term follow-up of drug-eluting stents in the treatment of chronic total occlusion (CTO). The LEADERS CTO sub-study compared the long-term results in CTO and non-CTO lesions of a Biolimus A9™-eluting stent (BES) with a sirolimus-eluting stent (SE

  16. Five-year outcomes of chronic total occlusion treatment with a biolimus A9-eluting biodegradable polymer stent versus a sirolimus-eluting permanent polymer stent in the LEADERS all-comers trial

    NARCIS (Netherlands)

    M. Ghione (Matteo); J.J. Wykrzykowska (Joanna); S. Windecker (Stephan); P.W.J.C. Serruys (Patrick); P.E. Buszman (Pawel); A. Linke (Axel); H.Y. Sohn (Hae Y); R. Corti (Roberto); M.L. Antoni (Louisa); W. Wijns (William); Estevez-Loureiro, R. (Rodrigo); M-C. Morice (Marie-Claude); G.A. van Es (Gerrit Anne); R.J.M. van Geuns (Robert Jan); P. Jùni (Peter); P. Eerdmans (Pedro); T. de Vries (Ton); Konik, S. (Stéphanie); C. di Mario (Carlo)

    2016-01-01

    textabstractBackground: Few data are available on long-term follow-up of drug-eluting stents in the treatment of chronic total occlusion (CTO). The LEADERS CTO sub-study compared the long-term results in CTO and non-CTO lesions of a Biolimus A9™-eluting stent (BES) with a sirolimus-eluting stent (SE

  17. Electrospun Poly(l-lactide)/Poly(ethylene glycol) Scaffolds Seeded with Human Amniotic Mesenchymal Stem Cells for Urethral Epithelium Repair

    Science.gov (United States)

    Lv, Xiaokui; Guo, Qianping; Han, Fengxuan; Chen, Chunyang; Ling, Christopher; Chen, Weiguo; Li, Bin

    2016-01-01

    Tissue engineering-based urethral replacement holds potential for repairing large segmental urethral defects, which remains a great challenge at present. This study aims to explore the potential of combining biodegradable poly(l-lactide) (PLLA)/poly(ethylene glycol) (PEG) scaffolds and human amniotic mesenchymal cells (hAMSCs) for repairing urethral defects. PLLA/PEG fibrous scaffolds with various PEG fractions were fabricated via electrospinning. The scaffolds were then seeded with hAMSCs prior to implantation in New Zealand male rabbits that had 2.0 cm-long defects in the urethras. The rabbits were randomly divided into three groups. In group A, hAMSCs were grown on PLLA/PEG scaffolds for two days and then implanted to the urethral defects. In group B, only the PLLA/PEG scaffolds were used to rebuild the rabbit urethral defect. In group C, the urethral defect was reconstructed using a regular urethral reparation technique. The repair efficacy was compared among the three groups by examining the urethral morphology, tissue reconstruction, luminal patency, and complication incidence (including calculus formation, urinary fistula, and urethral stricture) using histological evaluation and urethral radiography methods. Findings from this study indicate that hAMSCs-loaded PLLA/PEG scaffolds resulted in the best urethral defect repair in rabbits, which predicts the promising application of a tissue engineering approach for urethral repair. PMID:27517902

  18. Electrospun Poly(l-lactide/Poly(ethylene glycol Scaffolds Seeded with Human Amniotic Mesenchymal Stem Cells for Urethral Epithelium Repair

    Directory of Open Access Journals (Sweden)

    Xiaokui Lv

    2016-08-01

    Full Text Available Tissue engineering-based urethral replacement holds potential for repairing large segmental urethral defects, which remains a great challenge at present. This study aims to explore the potential of combining biodegradable poly(l-lactide (PLLA/poly(ethylene glycol (PEG scaffolds and human amniotic mesenchymal cells (hAMSCs for repairing urethral defects. PLLA/PEG fibrous scaffolds with various PEG fractions were fabricated via electrospinning. The scaffolds were then seeded with hAMSCs prior to implantation in New Zealand male rabbits that had 2.0 cm-long defects in the urethras. The rabbits were randomly divided into three groups. In group A, hAMSCs were grown on PLLA/PEG scaffolds for two days and then implanted to the urethral defects. In group B, only the PLLA/PEG scaffolds were used to rebuild the rabbit urethral defect. In group C, the urethral defect was reconstructed using a regular urethral reparation technique. The repair efficacy was compared among the three groups by examining the urethral morphology, tissue reconstruction, luminal patency, and complication incidence (including calculus formation, urinary fistula, and urethral stricture using histological evaluation and urethral radiography methods. Findings from this study indicate that hAMSCs-loaded PLLA/PEG scaffolds resulted in the best urethral defect repair in rabbits, which predicts the promising application of a tissue engineering approach for urethral repair.

  19. Electrospun Poly(l-lactide)/Poly(ethylene glycol) Scaffolds Seeded with Human Amniotic Mesenchymal Stem Cells for Urethral Epithelium Repair.

    Science.gov (United States)

    Lv, Xiaokui; Guo, Qianping; Han, Fengxuan; Chen, Chunyang; Ling, Christopher; Chen, Weiguo; Li, Bin

    2016-08-09

    Tissue engineering-based urethral replacement holds potential for repairing large segmental urethral defects, which remains a great challenge at present. This study aims to explore the potential of combining biodegradable poly(l-lactide) (PLLA)/poly(ethylene glycol) (PEG) scaffolds and human amniotic mesenchymal cells (hAMSCs) for repairing urethral defects. PLLA/PEG fibrous scaffolds with various PEG fractions were fabricated via electrospinning. The scaffolds were then seeded with hAMSCs prior to implantation in New Zealand male rabbits that had 2.0 cm-long defects in the urethras. The rabbits were randomly divided into three groups. In group A, hAMSCs were grown on PLLA/PEG scaffolds for two days and then implanted to the urethral defects. In group B, only the PLLA/PEG scaffolds were used to rebuild the rabbit urethral defect. In group C, the urethral defect was reconstructed using a regular urethral reparation technique. The repair efficacy was compared among the three groups by examining the urethral morphology, tissue reconstruction, luminal patency, and complication incidence (including calculus formation, urinary fistula, and urethral stricture) using histological evaluation and urethral radiography methods. Findings from this study indicate that hAMSCs-loaded PLLA/PEG scaffolds resulted in the best urethral defect repair in rabbits, which predicts the promising application of a tissue engineering approach for urethral repair.

  20. General Information about Urethral Cancer

    Science.gov (United States)

    ... Cancer Treatment Urethral Cancer Treatment (PDQ®)–Patient Version General Information About Urethral Cancer Go to Health Professional ... In men, the urethra also carries semen . Enlarge Anatomy of the male urinary system (left panel) and ...

  1. Posterior Urethral Valves

    Directory of Open Access Journals (Sweden)

    Steve J. Hodges

    2009-01-01

    Full Text Available The most common cause of lower urinary tract obstruction in male infants is posterior urethral valves. Although the incidence has remained stable, the neonatal mortality for this disorder has improved due to early diagnosis and intensive neonatal care, thanks in part to the widespread use of prenatal ultrasound evaluations. In fact, the most common reason for the diagnosis of posterior urethral valves presently is the evaluation of infants for prenatal hydronephrosis. Since these children are often diagnosed early, the urethral obstruction can be alleviated rapidly through catheter insertion and eventual surgery, and their metabolic derangements can be normalized without delay, avoiding preventable infant mortality. Of the children that survive, however, early diagnosis has not had much effect on their long-term prognosis, as 30% still develop renal insufficiency before adolescence. A better understanding of the exact cause of the congenital obstruction of the male posterior urethra, prevention of postnatal bladder and renal injury, and the development of safe methods to treat urethral obstruction prenatally (and thereby avoiding the bladder and renal damage due to obstructive uropathy are the goals for the care of children with posterior urethral valves[1].

  2. Urethral instability: current pathophysiological concept.

    NARCIS (Netherlands)

    Groenendijk, P.M.; Heesakkers, J.P.F.A.; Ouwerkerk, T.J.; Lycklama à Nijeholt, A.A.B.

    2009-01-01

    The role of urethral pressure variations during filling cystometry is seldom assessed as a potential cause of voiding dysfunction and/or storage disorders. In this article, we review current research in the field of urethral pressure variations and discuss the way of determining urethral pressure va

  3. Urethral instability: current pathophysiological concept.

    NARCIS (Netherlands)

    Groenendijk, P.M.; Heesakkers, J.P.F.A.; Ouwerkerk, T.J.; Lycklama à Nijeholt, A.A.B.

    2009-01-01

    The role of urethral pressure variations during filling cystometry is seldom assessed as a potential cause of voiding dysfunction and/or storage disorders. In this article, we review current research in the field of urethral pressure variations and discuss the way of determining urethral pressure va

  4. Parameatal urethral cyst

    Directory of Open Access Journals (Sweden)

    Aggarwal Kamal

    2008-01-01

    Full Text Available Cyst formation in the parameatal area of the urethra is an uncommon entity. It was first reported in two male cases as recently as 1956 by Thompson and Lantin. Further reports have been rare. Herein, we report a case of a 21 year-old male having a spherical, cystic swelling 1 cm in size at the external urethral meatus. The diagnosis of parameatal urethral cyst was made and the cyst was excised. Histopathological examination revealed a monolocular cyst lined with transitional cells. The postoperative period was uneventful.

  5. High Modulus Biodegradable Polyurethanes for Vascular Stents: Evaluation of Accelerated in vitro Degradation and Cell Viability of Degradation Products.

    Science.gov (United States)

    Sgarioto, Melissa; Adhikari, Raju; Gunatillake, Pathiraja A; Moore, Tim; Patterson, John; Nagel, Marie-Danielle; Malherbe, François

    2015-01-01

    We have recently reported the mechanical properties and hydrolytic degradation behavior of a series of NovoSorb™ biodegradable polyurethanes (PUs) prepared by varying the hard segment (HS) weight percentage from 60 to 100. In this study, the in vitro degradation behavior of these PUs with and without extracellular matrix (ECM) coating was investigated under accelerated hydrolytic degradation (phosphate buffer saline; PBS/70°C) conditions. The mass loss at different time intervals and the effect of aqueous degradation products on the viability and growth of human umbilical vein endothelial cells (HUVEC) were examined. The results showed that PUs with HS 80% and below completely disintegrated leaving no visual polymer residue at 18 weeks and the degradation medium turned acidic due to the accumulation of products from the soft segment (SS) degradation. As expected the PU with the lowest HS was the fastest to degrade. The accumulated degradation products, when tested undiluted, showed viability of about 40% for HUVEC cells. However, the viability was over 80% when the solution was diluted to 50% and below. The growth of HUVEC cells is similar to but not identical to that observed with tissue culture polystyrene standard (TCPS). The results from this in vitro study suggested that the PUs in the series degraded primarily due to the SS degradation and the cell viability of the accumulated acidic degradation products showed poor viability to HUVEC cells when tested undiluted, however particles released to the degradation medium showed cell viability over 80%.

  6. Efficacy and safety of a biodegradable polymer Cobalt-Chromium sirolimus-eluting stent (EXCEL2) in treating de novo coronary artery disease: A pooled analysis of the CREDIT II and CREDIT III trials.

    Science.gov (United States)

    Wang, Geng; Wang, Heyang; Xu, Bo; Yang, Yuejin; Yang, Zhiming; Li, Hui; Zhang, Zheng; Wang, Haichang; Yang, Lixia; Han, Yaling

    2017-03-01

    The safety and efficacy of the second-generation biodegradable polymer Cobalt-Chromium sirolimus-eluting stent (EXCEL2) in daily clinical practice remains unknown. Additionally, to meet the China Food and Drug Administration requirements, we conducted an objective performance criterion study from the CREDIT II and CREDIT III trials. CREDIT II was a randomized trial comparing the EXCEL2 versus EXCEL stent in patients with up to 2 de novo coronary lesions. CREDIT III was a prospective, single-arm study evaluating the efficacy and safety of EXCEL2 in broad types of de novo coronary artery lesions. This pooled analysis included patients in the CREDIT III and EXCEL2 arm of the CREDIT II trial. The primary outcome was 12-month target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction (TV-MI), and clinical indicated target lesion revascularization (CI-TLR). The patient-oriented composite endpoint (PoCE) of all-cause death, all MI, or any revascularization was also analyzed. A total of 833 patients were included, consisting of 625 in the CREDIT III trial and 208 in the EXCEL2 arm of the CREDIT II trial. Twelve-month TLF occurred in 6.1% patients, cardiac death in 0.4%, TV-MI in 5%, and CI-TLR in 1.1%. Additionally, 64 (7.7%) PoCE and 3 probable late stent thromboses (0.4%) were recorded. EXCEL2 stent met the objective performance criterion on efficacy and safety with a low level of 12-month TLF as well as stent thrombosis when treating patients with de novo coronary lesions. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  7. High modulus biodegradable polyurethanes for applications in cardiovascular stents: Evaluation of in-vitro degradation and cell viability

    Directory of Open Access Journals (Sweden)

    Melissa eSagarito

    2015-05-01

    Full Text Available We have recently reported the mechanical properties and hydrolytic degradation behaviour of a series of NovoSorb™ [1] biodegradable polyurethanes (PUs prepared by varying the hard segment (HS weight percentage from 60-100. In this study the in-vitro degradation behaviour of the PUs with and without extracellular matrix (ECM coating was investigated under accelerated hydrolytic degradation (phosphate buffer saline; PBS/70°C conditions to allow complete degradation. The mass loss at different time intervals and the effect of aqueous degradation products on the viability and growth of Human Umbilical Vein Endothelial Cells (HUVEC were examined.The results showed that for most PUs in the series the degradation medium turned acidic and the extent of this was dependent on the HS percentage. As the HS decreased, a drop in pH was observed, suggesting that the by-products of soft segment (SS degradation causing the solution to be acidic. Most of the samples were completely eroded by 18 weeks, except PU containing more than 70% HS which only showed partial degradation with no significant change in appearance. The cytotoxicity tests on HUVEC cells of the aqueous extracts obtained after 18 weeks incubation showed that toxicity was dependent on 3 factors: dose, percentage of HS and degradation time. HUVEC growth is similar to but not identical to that observed with tissue culture polystyrene (TCPS standard. The results from this in-vitro cytotoxicity study suggest that the mixture of degradation products formed during the accelerated degradation of this PU series are not toxic to cells under the experimental conditions used.

  8. Safety and efficacy of a novel abluminal groove-filled biodegradable polymer sirolimus-eluting stent for the treatment of de novo coronary lesions: 12-month results from the TARGET Ⅱ trial

    Institute of Scientific and Technical Information of China (English)

    Xu Bo; Zhao Yelin; Yang Yuejin; Zhang Ruiyan; Li Hui; Ma Changsheng; Chen Shaoliang

    2014-01-01

    Background In the TARGET I randomized controlled trial,the novel abluminal groove-filled biodegradable polymer sirolimus-eluting stent FIREHAWK proved non-inferior to the everolimus-eluting stent in nine-month in-stent late loss in single de novo coronary lesions.This study was aimed at evaluating clinical safety and effectiveness of FIREHAWK in a moderately complex population (including patients with small vessels,long lesions and multi-vessels),and at validating the ability of the SYNTAX score (SS) to predict clinical outcomes in patients treated with this latest generation drug-eluting stent.Methods TARGET Ⅱ was a prospective,multicenter,single-arm study with primary outcome of 12-month target lesion failure (TLF),including cardiac death,target vessel myocardial infarction (TV-MI) and ischemia-driven target lesion revascularization (TLR).Stent thrombosis was defined according to the Academic Research Consortium (ARC) definition.Patients were grouped by tertiles of SS (≤6,>6 to ≤12,and >12).All patients were exclusively treated with the FIREHAWK stent and were followed up at 1,6,and 12 months,and annually thereafter up to five years.Results A total of 730 patients were included in this registry study.The 12-month incidence of TLF was 4.4% and the incidence of TLF components were,cardiac death 0.5%,TV-MI 3.2%,and TLR 2.2%.One definite/probable stent thrombosis was observed at 12-month follow-up.Mean SS was 10.87±6.87.Patients in the SS >12 tertile had significantly higher TLF (P=0.02) and TLR (P <0.01) rates than those in lower SS groups.In COX proportional-hazards regression analyses,TLF incidence was strongly related to lesion length (long lesion vs.non-long lesion patients; HR 3.416,95% CI,1.622-7.195),but unrelated to diabetic,small vessel,and multivessel subgroups.Conclusions The low TLF incidence in this study indicates that FIREHAWK is safe and effective in the treatment of moderately complex coronary disease.SS is also able to

  9. 聚丙交酯/乙交酯胆道支架生物降解及与宿主的相容性%Biodegradability and biocompatibility of polylactide/glycolide biliary stent

    Institute of Scientific and Technical Information of China (English)

    施纯朝; 赵晓飞; 吴晓峰

    2015-01-01

    BACKGROUND:Biliary stent is widely used in different biliary tract surgeries, and there are some defects in the use of biliary stent. OBJECTIVE:To explore the biodegradability and compatibility of polylactide/glycolide biliary stent. METHODS:The polylactide/glycolide biliary stent was prepared, and immersed in the bile. At 1, 2, 3, 4 and 5 weeks after soaking, eight experimental stents were dried and placed under the scanning electron microscope. In the sterile condition, the stent was implanted under the rat skin. At 1, 2, 3, 4, and 5 weeks after implantation, two rats were sacrificed. The stent was taken out. The appearance of the stent and muscle structure of experimental animals was observed. The gross appearance of stent was observed at different time by scanning electron microscopy. The rate of degradation was calculated. The muscle structure of experimental animal and the stent were understood. RESULTS AND CONCLUSION:At 1 week, stent shape remained almost intact, but the texture became soft;surface roughness and cracks gradual y appeared;stent wal col apse was visible. The stent was completely degraded at 5 weeks. Before degradation, the stent presented clear three-dimensional reticular structure observed by scanning electron microscopy. With the time extended, the stent surface and section corrosion became worsened. By gel permeation chromatography detection, at 1 week of implantation, the molecular mass of the stent declined rapidly, and then gradual y declined. At 2 weeks, the relative molecular mass decreased to 15 000. At 4 weeks, stent mass loss was approximately 40%. Al the experimental animals were survived, no poisoning, al ergy or heat source response. The operative wound was healed wel , and no infection occurred. By histological observation, at 5 weeks, the stent was completely degraded, with a degradation rate of 100%. Surrounding muscles recovered to a normal state. These results indicate that the polylactide/glycolide biliary stent has good

  10. Treatments of the posterior urethral injury by simplified urethral realignment

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective To discuss a simple, safe and effective management for the the posterior urethral injury after pelvic fracture.Methods: The patients were treated by the simplified urethral realignment with traction; in the operation, the two -way catheter with an inner metal frame was implanted by the guidance of forefinger. After the operation, urethral dilation was processed regularly. Results 41 cases have been followed up and 36 cases can midurate normally, so the curative rate was 87. 8%. ln those, impotence occurred 3 cases. Conclusions The proper application of the urethral realignment with tradion followed by regular urethral dilation has an effecf on the patients of the the posterior urethral injury in pelvic fracture.

  11. 可降解脑血管支架材料生物相容性的系统评价%Systematical evaluation for the biocompatibility of biodegradable cerebrovascular stent materials

    Institute of Scientific and Technical Information of China (English)

    瞿浩; 李玫; 袁萍; 郭琴

    2011-01-01

    BACKGROUND: To select and develop cerebrovascular stent materials with a good bio com patb ility e currently a hot research OBJECTIVE: To systematically evaluate the b io co mp ati bi lity of biodegradable cerebrovascularstent materials, and to analyze the safety and prognosis after stent implantation.METHODS: A computer-based online search of Embase (1930/2011-08). MEDUNE (1966/2011-12).CBM(1978/2011-08)ar>d CHKI were performed for articles about animal experiments and clinical applications focusing on the bio compatibility of biodegradable cerebrovascularr stent materials.RESULTSAHD CONCLUSION: Of 24selected articles, 15 related animal experiments results show that various types of biodegradable cerebrovascularstent with good biocompatibilrty have favorable effects on preventing vascular thrombosis and restenosis by s up press ing endometrial hyperplasia. Nine related clinical experiments results show that biodegradable cerebrovascular stente can decrease the rate of restenosis and improve patients' prognosis; however, the safety needs long-term studies. Biodegradable cerebrovascular stent materials with good bio compatibility are effective and safe for cerebrovascular diseases. F urther studies with long-term follow-up are required to assess the restenosis rates in the intracranial vas culature.%背景:选择和开发具有良好生物相容性的脑血管支架材料是目前研究的热点.目的:系统评价可降解脑血管支架材料生物相容性的相关文献,客观分析生物可降解支架置入的安全性及预后.方法:计算机检索Embase(1980/2011-08)、MEDLINE(1966/2011-08)、中国生物医学文献数据库(CBM,1978/2011-08)、中文学术期刊全文数据库(CNKI)有关可降解脑血管支架生物相容性的动物实验和临床试验的文献,进行可归纳总结.结果与结论:共纳入24篇文章,15篇有关可降解脑血管支架材料生物相容性的动物实验结论均显示,多种可降解脑血管支架材料可抑制

  12. Anterior Urethral Valves

    Directory of Open Access Journals (Sweden)

    Vidyadhar P. Mali

    2006-07-01

    Full Text Available We studied the clinical presentation and management of four patients with anterior urethral valves; a rare cause of urethral obstruction in male children. One patient presented antenatally with oligohydramnios, bilateral hydronephrosis and bladder thickening suggestive of an infravesical obstruction. Two other patients presented postnatally at 1 and 2 years of age, respectively, with poor stream of urine since birth. The fourth patient presented at 9 years with frequency and dysuria. Diagnosis was established on either micturating cystourethrogram (MCU (in 2 or on cystoscopy (in 2. All patients had cystoscopic ablation of the valves. One patient developed a postablation stricture that was resected with an end-to-end urethroplasty. He had an associated bilateral vesicoureteric junction (VUJ obstruction for which a bilateral ureteric reimplantation was done at the same time. On long-term follow-up, all patients demonstrated a good stream of urine. The renal function is normal. Patients are continent and free of urinary infections. Anterior urethral valves are rare obstructive lesions in male children. The degree of obstruction is variable, and so they may present with mild micturition difficulty or severe obstruction with hydroureteronephrosis and renal impairment. Hence, it is important to evaluate the anterior urethra in any male child with suspected infravesical obstruction. The diagnosis is established by MCU or cystoscopy and the treatment is always surgical, either a transurethral ablation or an open resection. The long-term prognosis is good.

  13. Nine-month Angiographic and Two-year Clinical Follow-up of Novel Biodegradable-polymer Arsenic Trioxide-eluting Stent Versus Durable-polymer Sirolimus-eluting Stent For Coronary Artery Disease

    Directory of Open Access Journals (Sweden)

    Li Shen

    2015-01-01

    Full Text Available Background: Despite great reduction of in-stent restenosis, first-generation drug-eluting stents (DESs have increased the risk of late stent thrombosis due to delayed endothelialization. Arsenic trioxide, a natural substance that could inhibit cell proliferation and induce cell apoptosis, seems to be a promising surrogate of sirolimus to improve DES performance. This randomized controlled trial was to evaluate the efficacy and safety of a novel arsenic trioxide-eluting stent (AES, compared with traditional sirolimus-eluting stent (SES. Methods: Patients with symptoms of angina pectoris were enrolled and randomized to AES or SES group. The primary endpoint was target vessel failure (TVF, and the second endpoint includes rates of all-cause death, cardiac death or myocardial infarction, target lesion revascularization (TLR by telephone visit and late luminal loss (LLL at 9-month by angiographic follow-up. Results: From July 2007 to 2009, 212 patients were enrolled and randomized 1:1 to receive either AES or SES. At 2 years of follow-up, TVF rate was similar between AES and SES group (6.67% vs. 5.83%, P = 0.980. Frequency of all-cause death was significantly lower in AES group (0 vs. 4.85%, P = 0.028. There was no significant difference between AES and SES in frequency of TLR and in-stent restenosis, but greater in-stent LLL was observed for AES group (0.29 ± 0.52 mm vs. 0.10 ± 0.25 mm, P = 0.008. Conclusions: After 2 years of follow-up, AES demonstrated comparable efficacy and safety to SES for the treatment of de novo coronary artery lesions.

  14. Estudo Pré-Clínico de Stent com Polímero Biodegradável e Liberação Abluminal de Sirolimus

    Directory of Open Access Journals (Sweden)

    Celso Kiyochi Takimura

    2014-06-01

    Full Text Available Fundamento: Stents recobertos com polímeros bioabsorvíveis e fármacos apenas na face abluminal podem ser mais seguros que stents farmacológicos com polímeros permanentes. Objetivo: Relatar os resultados experimentais com o stent Inspiron(r, um stent recoberto com polímero bioabsorvível e com liberação de sirolimus apenas da face abluminal, recentemente aprovado para uso clínico. Métodos: Foram implantados 45 stents nas artérias coronárias de 15 porcos e, no 28° dia pós-implante, foram obtidos os resultados angiográficos, de ultrassonografia intracoronária e de histomorfologia. Cinco grupos foram avaliados: Grupo I (nove stents sem recobrimento; Grupo II (nove stents com polímero bioabsorvível nas faces luminal e abluminal; Grupo III (oito stents com polímero bioabsorvível na face abluminal; Grupo IV (nove stents com polímero bioabsorvível e sirolimus nas faces luminal e abluminal; e Grupo V (dez stents com polímero bioabsorvível e sirolimus na face abluminal exclusivamente. Resultados: Observamos, para os Grupos I, II, III, IV e V respectivamente: porcentual de estenose de 29 ± 20; 36 ± 14; 33 ± 19; 22 ± 13 e 26 ± 15 (p = 0,443; perda luminal tardia (em mm de 1,02 ± 0,60; 1,24 ± 0,48; 1,11 ± 0,54; 0,72 ± 0,44 e 0,78 ± 0,39 (p = 0,253; área neointimal (em mm2 de 2,60 ± 1,99; 2,74 ± 1,51; 2,74 ± 1,30; 1,30 ± 1,14 e 0,97 ± 0,84 (p = 0,001; Grupos IV e V versus Grupos I, II e III e porcentual de área neointimal de 35 ± 25; 38 ± 18; 39 ± 19; 19 ± 18 e 15 ± 12 (p = 0,001; Grupo IV e V versus Grupo I, II e III. Os escores de injúria e inflamação foram baixos e sem diferenças entre os grupos. Conclusão: O stent Inspiron(r foi seguro e inibiu significativamente a hiperplasia neointimal observada no 28° dia pós-implante em artérias coronárias porcinas.

  15. Stent placement for esophageal strictures : an update

    NARCIS (Netherlands)

    Hirdes, Meike Madeleine Catharine; Vleggaar, Frank Paul; Siersema, Peter Derk

    2011-01-01

    The use of stents for esophageal strictures has evolved rapidly over the past 10 years, from rigid plastic tubes to flexible self-expanding metal (SEMS), plastic (SEPS) and biodegradable stents. For the palliative treatment of malignant dysphagia both SEMS and SEPS effectively provide a rapid relief

  16. Tracheobronchial stents in children.

    Science.gov (United States)

    Antón-Pacheco, Juan L

    2016-06-01

    Tracheobronchial obstruction is infrequent in children and still remains a challenging matter of concern. Management alternatives vary from conservative treatment to complex surgical techniques or endoscopic interventional procedures. Airway stenting in children is relatively recent and follows the trail of the experience in adult patients. Nevertheless, there are basic differences between both age groups like the benign nature of most obstructions and the small size of the pediatric airway. These specific features raise the issues of the precise role of tracheobronchial stenting in children and the selection of the most adequate device. Stents fall into four main categories according to the material they are made of: metallic, plastic, hybrid, and biodegradable. Each type has its own advantages and drawbacks so the ideal stent is not yet available. Despite increasing experience with stenting, definite clinical criteria for their use in children are yet to be established. Even so, there seems to be a basic general agreement that stents may play a role in particular clinical settings in which there are no other therapeutic options. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Comparison of two biodegradable-polymer-based sirolimus-eluting stents with varying elution and absorption kinetics in patients with acute myocardial infarction: A subgroup analysis of the PANDA III trial.

    Science.gov (United States)

    Guan, Changdong; Xu, Bo; Qiao, Shubin; Qin, Lei; Li, Yi; Li, Zhanquan; Guo, Yong; Sun, Zhongwei; Song, Lei; Gao, Runlin

    2017-03-01

    Implantation of early-generation metallic drug-eluting stents (DES) in patients with acute myocardial infarction (AMI) is associated with poor vessel wall healing. Use of biodegradable polymer (BP) DES might improve safety outcomes; however, the impact of varying drug elution and polymer absorption kinetics of BP-DES on clinical outcomes in the AMI population is unknown. This subgroup analysis of the randomized PANDA III trial included 732 patients (366 in each group) presenting with recent (<1 month) AMI. Primary endpoint was 1-year target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction (MI), or ischemia-driven target lesion revascularization. Secondary endpoints included a patient-oriented composite endpoint (PoCE) of all-cause death, all MI, or any revascularization; individual TLF and PoCE components; and definite/probable stent thrombosis (ST). There were no significant differences between-groups in baseline clinical, angiographic, or procedural characteristics other than the proportion of post-dilatation, which was performed more frequently with the BuMA stent (53.9% vs. 44.5%; P = 0.004). After 1 year, compared to Excel SES implantation in patients with AMI, BuMA was associated with similar incidences of TLF and PoCE (5.5% vs. 8.3%, P = 0.14; 8.8% vs. 9.9%, P = 0.61, respectively) but lower incidences of MI (2.5% vs. 6.1%, P = 0.02), target vessel MI (2.2% vs. 5.8%, P = 0.01), and definite/probable ST (0.3% vs. 2.2%, P = 0.04). BuMA SES, with faster drug elution rate and polymer absorption kinetics, might improve safety outcomes compared to Excel SES in the high-risk AMI population. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  18. EAU Guidelines on Urethral Trauma.

    Science.gov (United States)

    Martínez-Piñeiro, Luis; Djakovic, Nenad; Plas, Eugen; Mor, Yoram; Santucci, Richard A; Serafetinidis, Efraim; Turkeri, Levent N; Hohenfellner, Markus

    2010-05-01

    These guidelines were prepared on behalf of the European Association of Urology (EAU) to assist urologists in the management of traumatic urethral injuries. To determine the optimal evaluation and management of urethral injuries by review of the world's literature on the subject. A working group of experts on Urological Trauma was convened to review and summarize the literature concerning the diagnosis and treatment of genitourinary trauma, including urethral trauma. The Urological Trauma guidelines have been based on a review of the literature identified using on-line searches of MEDLINE and other source documents published before 2009. A critical assessment of the findings was made, not involving a formal appraisal of the data. There were few high-powered, randomized, controlled trials in this area and considerable available data was provided by retrospective studies. The Working Group recognizes this limitation. The full text of these guidelines is available through the EAU Central Office and the EAU website (www.uroweb.org). This article comprises the abridged version of a section of the Urological Trauma guidelines. Updated and critically reviewed Guidelines on Urethral Trauma are presented. The aim of these guidelines is to provide support to the practicing urologist since urethral injuries carry substantial morbidity. The diversity of urethral injuries, associated injuries, the timing and availability of treatment options as well as their relative rarity contribute to the controversies in the management of urethral trauma. Copyright © 2010 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  19. Long term clinical comparison between Titanium nitric oxide biological availability stent and biodegradable polymer coated sirolimus-eluting stent%氮氧化钛生物有效性支架与生物可降解雷帕霉素药物洗脱支架长期临床对比研究

    Institute of Scientific and Technical Information of China (English)

    张孝忠; 张军; 王红; 张晋; 蒋静

    2011-01-01

    目的 对比研究氮氧化钛生物有效性支架(Titan2-BAS)与生物可降解雷帕霉素药物洗脱支架(Excel支架)在冠状动脉血运重建方面的临床疗效.方法 162例冠心病患者,根据植入的支架不同分为A组(Titan2-BAS)88例,B组(Excel)74例,均采用经桡动脉或尺动脉途径冠脉血运重建.A组阿司匹林与氯吡格雷双联抗血小板治疗1~3个月,B组至少6个月,此后长期单用阿司匹林.计算A、B两组支架病变的通过率、早期支架内血栓发生率及随访MACE发生率(指死亡、急性心肌梗死、靶血管重建等).结果 (1) A组141处>75%狭窄病变共植入Titan2-BAS支架152枚,1枚支架未能通过病变(RCA),通过率99.3%;B组114处病变共植入Excel支架120枚,通过率100%,两组差异无统计学意义(P>0.05).(2)随访10~18个月,平均13.8个月.两组均无死亡病例;A、B两组均无急、晚期血栓;A组1例术后6个月行靶血管重建,B组无靶血管重建;综合以上,两组MACE发生率差异无统计学意义(P>0.05).结论 在本研究样品量情况下,Titan2-BAS与Excel支架在冠脉血运重建方面的近期及远期疗效相近.%Objectives To compare the clinical efficacy of Titanium nitric-oxide biological availability stents(Titan2BAS) with biodegradable polymer coated sirolimus eluting stents (Excel) in practice of coronary revascularization.Methods 162 patients with coronary heart diseases were enrolled. Based on the different stents,88 patients were enrolled in group A treated with Titanium nitric oxide biological availability stent and other 74 patients enrolled in group B treated with biodegradable polymer coated sirolimus eluting stents. All the stents were implanted through either radial or ulnar artery approach. Patients in group A were administered with aspirin and clopidogrel for 1 to 3 months, while patients in group B for at least 6 months. Late aspirin for long term secondary prevention was reasonable. The stent delivery success rate

  20. Preliminary Evaluation of Clinical and Angiographic Outcomes with Biodegradable Polymer Coated Sirolimus-Eluting Stent in De Novo Coronary Artery Disease: Results of the MANIPAL-FLEX Study

    Directory of Open Access Journals (Sweden)

    Ranjan Shetty

    2016-01-01

    Full Text Available Objective. The objective of the MANIPAL-FLEX study was to evaluate the feasibility, preliminary safety, and efficacy of the Supraflex sirolimus-eluting stent (SES implantation, in de novo coronary artery disease, using clinical and quantitative coronary angiography (QCA follow-ups. Methods. This was a prospective, nonrandomized, multicenter, single-arm study that enrolled 189 patients with de novo coronary artery disease who were treated with the Supraflex SES. Of 189 patients enrolled, the first 61 consecutive patients who consented to a 9-month follow-up evaluation by QCA, irrespective of presence of symptoms, were to be followed up with angiography at 9 months. The primary endpoint of the study was target lesion failure (TLF, including cardiac death, myocardial infarction, and target lesion revascularization during 12-month follow-up after the index procedure. Results. The mean age of the study population was 58±11 years, with 51.3% (97/189 of hypertensive patients. Total of 66 lesions, analyzed by offline QCA, showed good scaffolding of the target vessel with in-stent late lumen loss at 9 months of 0.18±0.23 mm. The observed TLF at 30-day, 6-month, and 12-month follow-up were 2 (1.1%, 6 (3.2%, and 10 (5.3%, respectively. Conclusion. This study provides preliminary evidence for the feasibility, safety, and efficacy of the Supraflex sirolimus-eluting stent.

  1. Bronchial stents

    Directory of Open Access Journals (Sweden)

    Ibrahim Emad

    2006-01-01

    Full Text Available Bronchial stents are mostly used as a Palliative relief of symptoms often caused by airway obstruction, It is also used for sealing of stump fistulas after pneumonectomy and dehiscence after bronchoplastic operations. Advances in airway prosthetics have provided a variety of silicone stents, expandable metal stents, and pneumatic dilators, enabling the correction of increasingly complex anatomical problems. Several series have been published describing the application and results of these techniques. This manuscript reviews the historical development of stents, types, indication, outcome, and complications. Alternative therapies for tracheobronchial stenting were also reviewed

  2. The Supralimus sirolimus-eluting stent.

    Science.gov (United States)

    Lemos, Pedro A; Bienert, Igor

    2013-05-01

    The use of biodegradable polymeric coatings has emerged as a potential bioengineering target to improve the vascular compatibility of coronary drug-eluting stents (DESs). This review summarizes the main features and scientific facts about the Supralimus sirolimus-eluting stent (Sahajanand Medical Technologies Ltd, Surat, India), which is a biodegradable polymer-based, sirolimus-eluting metallic stent that was recently introduced for routine use in Europe. The novel stent is built on a stainless steel platform, coated with a blend of biodegradable polymers (poly-l-lactide, poly-dl-lactide-co-glycolide and polyvinyl pyrrolidone; coating thickness is 4-5 µm). The active agent is the antiproliferative sirolimus in a dose load of 1.4 µg/mm(2), which is released within 48 days. The Supralimus stent was initially evaluated in the single-arm SERIES-I study, which showed binary angiographic restenosis rates of 0% (in-stent) and 1.7% (in-segment) and an in-stent late lumen loss of 0.09 ± 0.28 mm. The multicenter randomized PAINT trial compared two DESs with identical metallic platforms and biodegradable polymer carriers, but different agents (Infinnium [Sahajanand Medical Technologies Pvt Ltd] paclitaxel-eluting stent or Supralimus sirolimus-eluting stent) against bare stents. After 3 years, the pooled DES population had similar rates of cardiac death or myocardial infarction (9 vs 7.1%; p = 0.6), but a lower risk of repeat interventions (10 vs 29.9%; p < 0.01) than controls with bare stents. The incidence of definite or probable stent thrombosis in the pooled DES group was 2.3% (1st year: 1.8%; 2nd year: 0.4% and 3rd year: 0%). These results demonstrate that the novel Supralimus stents are effective in reducing reintervention, while potentially improving the safety profile by decreasing the risk of late-term thrombosis, even though further studies would be necessary to confirm these findings.

  3. Mechanical properties of PLLA/HA biodegradable stent by electrospinning in the use of trachea stent%PLLA/HA复合材料电纺丝覆膜气管支架的制作及力学性能的基础研究

    Institute of Scientific and Technical Information of China (English)

    马永富; 刘阳; 梁朝阳; 郭俊唐; 张涛

    2013-01-01

    Objective To design a kind of electrospinning trachea stent with PLLA and HA composite, and its mechanical properties were studied. The structure of fiber membrane was observed. Methods PLLA/HA composite nanofiber was prepared by electrospinning method. The structure of fiber membrane was observed by scanning electron microscopy, and the mechanical properties were studied. Results The surface of hybrid fibers was much coarser because of the introduction of HA nano-particles, and the mechanical properties were well. Conclusion The properties of the biodegradable trachea stent with PLLA and HA composite is available for further study.%目的 自行研制羟基磷灰石/聚左旋乳酸(PLLA/HA)复合材料支架,测试机械力学性能;制备PLLA/HA复合纳米纤维膜,观察纤维膜的结构形态.方法 将一定比例HA复合于PLLA中,制膜切丝,自制支架,测试支架力学性能;电纺丝法行支架电纺丝覆膜,扫描电镜观察其形态.结果 PLLA/HA复合材料电纺丝覆膜支架的力学性能良好,结构形态符合组织工程材料要求.结论 PLLA/HA复合材料电纺丝覆膜支架可以满足气管内支架置入要求,是气管内支架的一种新型材料.

  4. Recent developments in drug-eluting coronary stents.

    Science.gov (United States)

    Yildiz, Mustafa; Yildiz, Banu Sahin; Gursoy, Mustafa Ozan; Akin, Ibrahim

    2014-01-01

    The interventional treatment of coronary artery disease was introduced in 1970`s by Andreas Grüntzig. The initial treatment strategy with plain old balloon angioplasty (POBA) was associated with high restenosis rates. The introduction of coronary stents, especially drug-eluting stents (DES) in 2002 has improved the results by lowering the rate of in-stent restenosis from 20-40% in the era of bare-metal stent (BMS) to 6-8%. However, in 2006 with the observation of late stent thrombosis the reputations of DES have decreased. However, improvements in stent design especially antiproliferative agents, polymeric agents as well as stent platforms improved newer generation DES. In controlled trials as well as registries the use of second-generation DES as compared to bare-metal stents (BMS) was associated with better clinical and angiographic results. A further development of these stents with use of biodegradable polymers, polymer-free stents, and biodegradable stents on the basis of poly L-lactide (PLLA) or magnesium resulted in third-generation DES and has been evaluated in preclinical and first clinical trials. However, to date, there is a lack of data comparing these third-generation DES with first- and second-generatrion DES in a large scale.

  5. Long-term urethral catheterisation.

    Science.gov (United States)

    Turner, Bruce; Dickens, Nicola

    This article discusses long-term urethral catheterisation, focusing on the relevant anatomy and physiology, indications for the procedure, catheter selection and catheter care. It is important that nurses have a good working knowledge of long-term catheterisation as the need for this intervention will increase with the rise in chronic health conditions and the ageing population.

  6. Vessel healings after stenting with different polymers in STEMI patients

    Science.gov (United States)

    Jin, Qin-Hua; Chen, Yun-Dai; Tian, Feng; Guo, Jun; Jing, Jing; Sun, Zhi-Jun

    2016-01-01

    Background Different stents implantation in ST-segment elevation myocardial infarction (STEMI) patients may influence the long term prognosis by affecting vessel healings after stenting. The aim of this study was to evaluate the vessel healings after implantation of drug eluting stents (DES) with biodegradable or durable polymer or of bare-metal stents (BMS) in patients with acute STEMI. Methods This study included 50 patients, who underwent follow up angiogram and optical coherence tomography (OCT) assessment about one year after percutaneous coronary intervention (PCI) for STEMI. According to the initial stents types, these patients were classified to durable (n = 19) or biodegradable polymer sirolimus-eluting stents (n = 15), or BMS (n = 16) groups. The conditions of stent struts coverage and malapposition were analyzed with OCT technique. Results A total of 9003 struts were analyzed: 3299, 3202 and 2502 from durable or biodegradable polymer DES, or BMS, respectively. Strut coverage rate (89.0%, 94.9% and 99.3%, respectively), malapposition presence (1.7%, 0.03% and 0 of struts, respectively) and average intimal thickness over struts (76 ± 12 µm, 161 ± 30 µm and 292 ± 29 µm, respectively) were significantly different among different stent groups (all P < 0.001). Conclusions Vessel healing status in STEMI patients is superior after implantation of biodegradable polymer DES than durable polymer DES, while both are inferior to BMS. PMID:27403139

  7. Coating bioabsorption and chronic bare metal scaffolding versus fully bioabsorbable stent.

    Science.gov (United States)

    Waksman, Ron; Pakala, Rajbabu

    2009-12-15

    Advances in coronary stent technology, including refinement of the stent alloy, strut thickness, stent geometry, passive coating, and drug elution, have dramatically enhanced the safety and efficacy of percutaneous coronary intervention (PCI) with stenting. Stents are currently used in over 90% of coronary interventions and the use of drug-eluting stents (DES) has been disseminated to more complex lesion subsets such as total occlusions, long lesions, bifurcation lesions, and for patients with acute myocardial infarction. DES continue to demonstrate reduction in restenosis and the need for repeat revascularisation but are associated with delayed healing and re-endothelialisation, which have led to an increased rates of late stent thrombosis, dependency on prolonged dual antiplatelet therapy, impaired in-vessel reactivity, and chronic inflammation. As scientists and clinicians better understand the mechanism for late restenosis and stent thrombosis, a variety of solutions in regard to stent technology have been proposed, including stent coating, polymer bioabsorption, and fully biodegradable stents. Bare metal stents were improved by the reduction of strut thickness, changes in stent geometry, and the addition of passive coating, which lead to improvements in efficacy and reduction of restenosis. In addition, there is continued improvement in the polymer technology for DES, including new biocompatible, thinner durable polymers, and bioabsorbable polymers that completely bioabsorb within 3-12 months after stent implantation. These features potentially minimise the chronic inflammatory response and late stent thrombosis. Finally, fully bioabsorbable stents, both polymeric and metallic, continue to be developed in order to eliminate any late stenting effects and potentially may enable complete vessel restoration. This manuscript will discuss the wide variety of new stent technologies and compare and contrast durable metallic and polymeric stents to current

  8. Stents: Biomechanics, Biomaterials, and Insights from Computational Modeling.

    Science.gov (United States)

    Karanasiou, Georgia S; Papafaklis, Michail I; Conway, Claire; Michalis, Lampros K; Tzafriri, Rami; Edelman, Elazer R; Fotiadis, Dimitrios I

    2017-04-01

    Coronary stents have revolutionized the treatment of coronary artery disease. Improvement in clinical outcomes requires detailed evaluation of the performance of stent biomechanics and the effectiveness as well as safety of biomaterials aiming at optimization of endovascular devices. Stents need to harmonize the hemodynamic environment and promote beneficial vessel healing processes with decreased thrombogenicity. Stent design variables and expansion properties are critical for vessel scaffolding. Drug-elution from stents, can help inhibit in-stent restenosis, but adds further complexity as drug release kinetics and coating formulations can dominate tissue responses. Biodegradable and bioabsorbable stents go one step further providing complete absorption over time governed by corrosion and erosion mechanisms. The advances in computing power and computational methods have enabled the application of numerical simulations and the in silico evaluation of the performance of stent devices made up of complex alloys and bioerodible materials in a range of dimensions and designs and with the capacity to retain and elute bioactive agents. This review presents the current knowledge on stent biomechanics, stent fatigue as well as drug release and mechanisms governing biodegradability focusing on the insights from computational modeling approaches.

  9. Indwelling urethral catheters in adults

    OpenAIRE

    Calleja, Edward

    2012-01-01

    This article focuses on indwelling urethral catheters in adults, their indications for the short and long term use, the types of urinary catheters available in Malta, an overview of the basic structure of a catheter, and the complications of urinary catheter insertion and maintenance. An attempt has been made to address in some depth the most common complication of indwelling catheters – catheter associated urinary tract infection in terms of pathophysiology and its management. Simple but cru...

  10. Urethral sensitivity in incontinent women.

    Science.gov (United States)

    Kinn, A-C; Nilsson, B Y

    2005-07-01

    The aim of this study was to ascertain whether frequent voiding and urge incontinence are associated with supersensitivity to electrical stimulation in the posterior urethra. Current perception thresholds (CPT) were tested at four stimulus frequencies (1, 3, 20, and 100 Hz; duration 0.5 ms) using a square-wave constant current electrical stimulator connected to ring electrodes on a urethral catheter. The strength of the current at the first tingling sensation was regarded as the CPT. CPT analysis and cystometry were performed on 61 women (ages 28-89 years). CPTs were significantly higher at lower than at elevated stimulus frequencies, and they were also generally higher in old than in younger patients. Seven women repeated the CPT test after two months, and the thresholds were unchanged. There were no significant differences in sensitivity between patient groups with stress incontinence, urge, or mixed symptoms. Moreover, CPT was not significantly related to bladder volume at first sensation of filling. Measuring CPT is an easy and reproducible method of testing urethral sensibility, but our results do not support the suspicion that urethral hypersensitivity is involved in increased voiding frequency and urge incontinence.

  11. Characterization and in vivo evaluation of a bio-corrodible nitrided iron stent.

    Science.gov (United States)

    Feng, Qimao; Zhang, Deyuan; Xin, Chaohua; Liu, Xiangdong; Lin, Wenjiao; Zhang, Wanqian; Chen, Sun; Sun, Kun

    2013-03-01

    A bio-corrodible nitrided iron stent was developed using a vacuum plasma nitriding technique. In the nitrided iron stents, the tensile strength, radial strength, stiffness and in vitro electrochemical corrosion rate were significantly increased compared with those of the control pure iron stent. To evaluate its performance in vivo, the deployment of the nitrided iron stents in juvenile pig iliac arteries was performed. At 3 or 6 months postoperatively, the stented vessels remained patent well; however, slight luminal loss resulting from intimal hyperplasia and relative stenosis of the stented vessel segment with piglets growth were observed by 12 months; no thrombosis or local tissue necrosis was found. At 1 month postoperatively, a nearly intact layer of endothelial cells formed on the stented vessel wall. Additionally, a decreased inflammation scoring, considerably corroded struts and corrosion products accumulation were seen. These findings indicate the potential of this nitrided iron stent as an attractive biodegradable stent.

  12. Anterior urethral diverticulum: A rare presentation

    Directory of Open Access Journals (Sweden)

    Annavarupu Gopalkrishna

    2016-01-01

    Full Text Available Congenital anomalies of the urogenital tract are the most common anomalies found in the foetus, neonates and infants, but anterior urethral valves and diverticula are rare. Here, we present a case with congenital anterior urethral diverticulum associated with patent ductus arteriosus and polydactyly.

  13. Intelligent Optimization of the Film-to-Fiber Ratio of a Degradable Braided Bicomponent Ureteral Stent

    Directory of Open Access Journals (Sweden)

    Xiaoyan Liu

    2015-11-01

    Full Text Available A hierarchical support vector regression (SVR model (HSVRM was employed to correlate the compositions and mechanical properties of bicomponent stents composed of poly(lactic-co-glycolic acid (PGLA film and poly(glycolic acid (PGA fibers for urethral repair for the first time. PGLA film and PGA fibers could provide ureteral stents with good compressive and tensile properties, respectively. In bicomponent stents, high film content led to high stiffness, while high fiber content resulted in poor compressional properties. To simplify the procedures to optimize the ratio of PGLA film and PGA fiber in the stents, a hierarchical support vector regression model (HSVRM and particle swarm optimization (PSO algorithm were used to construct relationships between the film-to-fiber weight ratio and the measured compressional/tensile properties of the stents. The experimental data and simulated data fit well, proving that the HSVRM could closely reflect the relationship between the component ratio and performance properties of the ureteral stents.

  14. Podophyllin induced urethral stricture in a young Nigerian male

    Directory of Open Access Journals (Sweden)

    P.O. Areo

    2015-09-01

    Full Text Available Urethral stricture is an abnormal narrowing or loss of distensibility due to fibrosis in the peri-urethral tissues. Some substances can induce chemical urethritis severe enough to cause stricture. We present a case of long segment anterior urethral stricture in a young Nigerian patient cause by self-application of podophyllin for the treatment of genital warts.

  15. Gastrointestinal stenting

    Energy Technology Data Exchange (ETDEWEB)

    Zollikofer, C.L.; Schoch, E. [Dept. of Radiology, Kantonsspital Winterthur (Switzerland); Jost, R. [Dept. of Gastroenterology Internal Medicine, Kantonsspital Winterthur (Switzerland); Decurtins, M. [Dept. of Surgery, Kantonsspital Winterthur (Switzerland)

    2000-02-01

    Acute obstructions of the gastric outlet, the duodenum, or the large bowel require rapid treatment to relieve symptoms of retention or ileus. Large-caliber stents of 16 to 22 mm offer a new non-surgical alternative for treating these patients with minimal risks and high success rates. For gastroduodenal outlet obstructions palliated by self-expanded metal stents, clinical success rates are in the range of 80-100 %. Preoperative treatment of colorectal obstructions successfully relieves acute symptoms of ileus in 87-100 % allowing primary anastomosis and thereby reducing the costs caused by multiple operations and the need of intensive care by approximately 25 %. It is the purpose of this review to familiarize the reader with the indications, possibilities, and limits of intestinal stenting. (orig.)

  16. Second- and third-generation drug-eluting coronary stents: progress and safety.

    Science.gov (United States)

    Akin, I; Schneider, H; Ince, H; Kische, S; Rehders, T C; Chatterjee, T; Nienaber, C A

    2011-05-01

    Drug-eluting stents (DES) have revolutionized the treatment of coronary artery disease by reducing the rate of in-stent restenosis from 20-40% with bare-metal stent (BMS) to 6-8% with DES. However, with widespread use of DES, safety concerns have risen due to the observation of late stent thrombosis. With this in mind and better understanding of mechanism and pathophysiology of stent thrombosis, the technological platform, especially innovative anti-restenotic agents, polymeric coatings, and stent platforms, improved with newer DES. Two second-generation DES, the Endeavor zotarolimus-eluting stent (ZES) and the Xience-V everolimus-eluting stent (EES), have provided promising results in both randomized controlled trials (SPIRIT and ENDEAVOR) and registries (E-Five, COMPARE) compared with bare-metal stents (BMS) and first-generation DES. Newer third-generation stent technology, especially biodegradable polymers, polymer-free stents, and biodegradable stents on the basis of poly-L-lactide (PLLA) or magnesium, has been evaluated in preclinical and initial clinical trials. However, despite encouraging initial results, long-term data of large-scale randomized trials as well as registries comparing them to currently approved first- and second-generation DES are still lacking.

  17. Sirolimus-eluting stent with biodegradable polymer coating in treatment of patients with coronary heart disease%可降解涂层雷帕霉素洗脱支架(Tivoli支架)治疗冠状动脉性心脏病的疗效

    Institute of Scientific and Technical Information of China (English)

    高力明; 游晓华; 徐荣良; 秦永文

    2012-01-01

    目的 评价国产可降解涂层雷帕霉素洗脱支架(Tivoli支架)用于冠状动脉性心脏病(CHD)患者介入治疗的安全性和近期疗效.方法 2010年9-11月于第二军医大学附属长海医院心血管内科单一植入Tivoli支架的CHD患者167例.术后接受双联抗血小板治疗9个月,观察主要心血管不良事件(MACE)的发生情况,并在术后12个月复查冠状动脉造影.结果 223处靶血管病变共使用Tivoli支架267枚,植入支架成 功率达100%.术后12个月冠状动脉造影随访结果显示,支架内再狭窄的发生率为1.9%(4/211),无1例发生MACE.结论 Tivoli支架治疗CHD是可行的,且具有良好的安全性和满意的近期临床效果.%Objective To evaluate the safety and short-term effectiveness of sirolimus-eluting stents with biodegradable polymer coating (Tivoli stents made in China) in the treatment of patients with coronary heart disease (CHD). Methods From September 2010 to November 2010, 167 CHD patients were treated by percutaneous coronary intervention (PCI) with Tivoli stents. All the patients received dual antiplatelet medication as clopidogrel and aspirin for 9 months postoperatively. The major adverse cardiac events (MACE) were observed. And angiography was performed 12 months after PCI. Results In 223 vascular lesions, 267 Tivoli stents were successfully implanted and the success rate was 100%. Angiography showed that the incidence rate of in-stent restenosis was 1.9% (4/211). No MACE happened during the follow-up. Conclusion The implantation of Tivoli stent is safe and effective for the CHD patients in the short term.

  18. Urethritis

    Science.gov (United States)

    ... Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic Disorders Immune Disorders Infections Injuries and Poisoning Kidney and ... Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic Disorders Immune Disorders Infections Injuries and Poisoning Kidney and ...

  19. Urethral syndrome” in women

    Directory of Open Access Journals (Sweden)

    Sławomir Dutkiewicz

    2013-08-01

    Full Text Available A contemporary overview of knowledge is presented on the subject of the so-called urethral syndrome in women, the causes of which have yet to be clearly identified. For practical reasons, the following three forms of the syndrome have been distinguished: interstitial cystitis, the “infectious” form and the “clean” form. In women who do not show symptoms of inflammation of the reproductive organs, bacterial urethritis should be distinguished from the urethral syndrome by evaluating the symptoms, the bacteriological tests and the risk of infection.

  20. Allium Stents: A Novel Solution for the Management of Upper and Lower Urinary Tract Strictures.

    Science.gov (United States)

    Bahouth, Zaher; Moskovitz, Boaz; Halachmi, Sarel; Nativ, Ofer

    2017-08-22

    Stents are widely use in endoscopic urological procedures. One of the most important indications is the treatment of urinary tract strictures. Allium(™) Medical has introduced several types of stents for the treatment of different types of urinary tract strictures, based on anatomic location. All the stents are made of nitinol and coated with a co-polymer that reduces encrustations. These stents are self-expandable and have a large caliber and a high radial force. They have different shapes, designed especially for the treatment of each type of stricture. One of the most important features of Allium-manufactured stents is the ease of removal, due to their special unraveling feature. The company has introduced the Bulbar Urethral Stent (BUS) for treatment of bulbar urethral strictures; a rounded stent available in different lengths. Initial data on 64 patients with bulbar urethral stricture treated with the BUS showed a significant improvement in symptoms, with minimal complications and few adverse events. For treatment of prostate obstruction in patients unfit for surgery or unwilling to undergo a classical prostatic surgery, the Triangular Prostatic Stent (TPS) was introduced, which has a triangular shape that fits in the prostatic urethra. Its body has a high radial force attached to an anchor (which prevents migration) through a trans-sphincteric wire (which reduces incontinence rate). Initial data on 51 patients showed significant improvement in symptoms and in urinary peak flow rate, with a relatively small number of complications. The Round Posterior Stent (RPS) was designed for treatment of post radical prostatectomy bladder neck contracture. This short, round stent has an anchor, which is placed in the bladder neck. This stent being relatively new, the clinical data are still limited. Ureteral strictures can be treated with the Ureteral Stent (URS), which is round-shaped, available in different lengths, and has an anchor option (for very distal or very

  1. Current management of urethral stricture disease

    Directory of Open Access Journals (Sweden)

    Thomas G Smith

    2016-01-01

    Conclusions: Progress is being made toward consistent terminology, and nomenclature which will, in turn, help to standardize treatment within the field of urology. Treatment for urethral stricture and stenosis remains inconsistent between reconstructive and nonreconstructive urologists due to varying treatment algorithms and approaches to disease management. Tissue engineering appears to be future for reconstructive urethral surgery with reports demonstrating feasibility in the use of different tissue substitutes and grafts.

  2. Coronary Stent Materials and Coatings: A Technology and Performance Update.

    Science.gov (United States)

    O'Brien, Barry; Zafar, Haroon; Ibrahim, Ahmad; Zafar, Junaid; Sharif, Faisal

    2016-02-01

    This paper reviews the current state of the art for coronary stent materials and surface coatings, with an emphasis on new technologies that followed on from first-generation bare metal and drug-eluting stents. These developments have been driven mainly by the need to improve long term outcomes, including late stent thrombosis. Biodegradable drug-eluting coatings aim to address the long term effects of residual durable polymer after drug elution; the SYNERGY, BioMatrix, and Nobori stents are all promising devices in this category, with minimal polymer through the use of abluminal coatings. Textured stent surfaces have been used to attached drug directly, without polymer; the Yukon Choice and BioFreedom stents have some promising data in this category, while a hydroxyapatite textured surface has had less success. The use of drug-filled reservoirs looked promising initially but the NEVO device has experienced both technical and commercial set-backs. However this approach may eventually make it to market if trials with the Drug-Filled Stent prove to be successful. Non-pharmacological coatings such as silicon carbide, carbon, and titanium-nitride-oxide are also proving to have potential to provide better performance than BMS, without some of the longer term issues associated with DES. In terms of biological coatings, the Genous stent which promotes attachment of endothelial progenitor cells has made good progress while gene-eluting stents still have some practical challenges to overcome. Perhaps the most advancement has been in the field of biodegradable stents. The BVS PLLA device is now seeing increasing clinical use in many complex indications while magnesium stents continue to make steady advancements.

  3. Symptomatic stent cast.

    Science.gov (United States)

    Keohane, John; Moore, Michael; O'Mahony, Seamus; Crosbie, Orla

    2008-02-01

    Biliary stent occlusion is a major complication of endoscopic stent insertion and results in repeat procedures. Various theories as to the etiology have been proposed, the most frequently studied is the attachment of gram negative bacteria within the stent. Several studies have shown prolongation of stent patency with antibiotic prophylaxis. We report the case of stent occlusion from a cast of a previously inserted straight biliary stent; a "stent cast" in an 86-year-old woman with obstructive jaundice. This was retrieved with the lithotrypter and she made an uneventful recovery. This is the first reported case of a biliary stent cast.

  4. Symptomatic stent cast.

    LENUS (Irish Health Repository)

    Keohane, John

    2012-02-03

    Biliary stent occlusion is a major complication of endoscopic stent insertion and results in repeat procedures. Various theories as to the etiology have been proposed, the most frequently studied is the attachment of gram negative bacteria within the stent. Several studies have shown prolongation of stent patency with antibiotic prophylaxis. We report the case of stent occlusion from a cast of a previously inserted straight biliary stent; a "stent cast" in an 86-year-old woman with obstructive jaundice. This was retrieved with the lithotrypter and she made an uneventful recovery. This is the first reported case of a biliary stent cast.

  5. [Development of biodegradable magnesium-based biomaterials].

    Science.gov (United States)

    Zhu, Shengfa; Xu, Li; Huang, Nan

    2009-04-01

    Magnesium is a macroelement which is indispensable to human bodies. As a lightweight metal with high specific strength and favorable biocompatibility, magnesium and its alloys have been introduced in the field of biomedical materials research and have a broad application prospect. It is possible to develop new type of biodegradable medical magnesium alloys by use of the poor corrosion resistance of magnesium. Bioabsorbable magnesium stents implanted in vivo could mechanically support the vessel in a short term, effectly prevent the acute coronary occlusion and in-stent restenosis, and then be gradully biodegraded and completely absorbed in a long term. Osteoconductive bioactivity in magnesium-based alloys could promote the apposition growth of bone tissue. This paper reviews the progress of magnesium and its alloys applied in bone tissue and cardiovascular stents, and the prospect of the future research of magnesium-based biomaterials is discussed.

  6. Development and characterization of a coronary polylactic acid stent prototype generated by selective laser melting.

    Science.gov (United States)

    Flege, Christian; Vogt, Felix; Höges, Simon; Jauer, Lucas; Borinski, Mauricio; Schulte, Vera A; Hoffmann, Rainer; Poprawe, Reinhart; Meiners, Wilhelm; Jobmann, Monika; Wissenbach, Konrad; Blindt, Rüdiger

    2013-01-01

    In-stent restenosis is still an important issue and stent thrombosis is an unresolved risk after coronary intervention. Biodegradable stents would provide initial scaffolding of the stenosed segment and disappear subsequently. The additive manufacturing technology Selective Laser Melting (SLM) enables rapid, parallel, and raw material saving generation of complex 3- dimensional structures with extensive geometric freedom and is currently in use in orthopedic or dental applications. Here, SLM process parameters were adapted for poly-L-lactid acid (PLLA) and PLLA-co-poly-ε-caprolactone (PCL) powders to generate degradable coronary stent prototypes. Biocompatibility of both polymers was evidenced by assessment of cell morphology and of metabolic and adhesive activity at direct and indirect contact with human coronary artery smooth muscle cells, umbilical vein endothelial cells, and endothelial progenitor cells. γ-sterilization was demonstrated to guarantee safety of SLM-processed parts. From PLLA and PCL, stent prototypes were successfully generated and post-processing by spray- and dip-coating proved to thoroughly smoothen stent surfaces. In conclusion, for the first time, biodegradable polymers and the SLM technique were combined for the manufacturing of customized biodegradable coronary artery stent prototypes. SLM is advocated for the development of biodegradable coronary PLLA and PCL stents, potentially optimized for future bifurcation applications.

  7. Drug-eluting stents, restenosis and revascularization.

    Science.gov (United States)

    Ramcharitar, Steve; Gaster, Anne Louise; Daemen, Joost; Serruys, Patrick

    2007-06-01

    Several meta-analyses have demonstrated the superiority of drug-eluting stents (DES) in reducing the incidence of restenosis, target vessel revascularization and target lesion revascularization compared to their predecessor, the bare-metal stent. In comparing Cypher and Taxus stents, the two most recent meta-analyses have given the edge to the Cypher. However, it must be stressed that the superiority of one DES over another remains debatable due to ever changing "real-world data" compared to those attained from randomized trials. The newer sirolimus analogs and selective inhibitors are challenging the old guard in their quest to further limit restenosis. So too are the newer "high-tech" polymers and additionally by using more biodegradable material in the stent's design. Stents aimed at targeting lesions are a new armament in the battle against restenosis and together with combination therapies are exciting key areas to watch. The ideal way to treat a DES in-stent restenosis is still a challenge and hence the impetus is to avoid it from happening in the first place.

  8. Ultrasonic fragmentation in the treatment of male urethral calculi.

    Science.gov (United States)

    Durazi, M H; Samiei, M R

    1988-11-01

    In the last 8 months, 7 patients have presented with acute retention of urine due to impacted urethral stones. Four stones were in the posterior urethra, 2 in the penile urethra and 1 proximal to the external urethral meatus. The patients were managed as emergencies. Stone fragmentation by ultrasound (US) through a 24F obliquely offset eyepiece nephroscope was achieved with minimal urethral trauma. Follow-up was for 6 months and no evidence of urethral stricture or recurrent stones was found. It was concluded that US fragmentation of urethral calculi is a safe and efficient procedure with minimal complications when used in the management of impacted urethral stones.

  9. Erectile dysfunction in urethral stricture and pelvic fracture urethral injury patients: diagnosis, treatment, and outcomes.

    Science.gov (United States)

    Sangkum, P; Levy, J; Yafi, F A; Hellstrom, W J G

    2015-05-01

    Urethral stricture disease, pelvic fracture urethral injury (PFUI), and their various treatment options are associated with erectile dysfunction (ED). The etiology of urethral stricture disease is multifactorial and includes trauma, inflammatory, and iatrogenic causes. Posterior urethral injuries are commonly associated with pelvic fractures. There is a spectrum in the severity of both conditions and this directly impacts the treatment options offered by the surgeon. Many published studies focus on the treatment outcomes and the relatively high recurrence rates after surgical repair. This communication reviews the current knowledge of the association between ED and urethral stricture disease, as well as PFUI. The incidence, pathophysiology, and clinical ramifications of both conditions on sexual function are discussed. The treatment options for ED in those patients are reviewed and summarized. © 2015 American Society of Andrology and European Academy of Andrology.

  10. Efficacy and safety of FIREHAWK(R) abluminal groove filled biodegradable polymer sirolimus-eluting stents for the treatment of long coronary lesions: nine-month angiographic and one-year clinical results from TARGET I trial long cohort

    Institute of Scientific and Technical Information of China (English)

    XU Bo; GAO Run-lin; ZHANG Rui-yan; WANG Hai-chang; LI Zhan-quan; YANG Yue-jin; MA Chang-sheng

    2013-01-01

    Background Previous studies indicated that long coronary lesions are one of the key predictors of drug-eluting stent (DES) failure.The purpose of this study was to evaluate the efficacy and the safety of the long length FIREHAWK(R) stent in long coronary artery disease.Methods The long cohort of TARGET I was a prospective,multicenter,single arm trial.It was planned to enroll 50 patients undergoing percutaneous coronary intervention (PCI) for the treatment of de novo long lesions in a native coronary artery.The major inclusion criteria of the trial was that patients were intended to undergo the treatment of a long target lesion(s) with diameter stenosis ≥70% and reference vessel diameter 2.5 mm to 4.0 mm by visual estimate,that needed to be covered by at least one 33 mm or 38 mm stent or multiple long stents overlapped.The angiographic follow-up was planned at 9-month and the clinical follow-up will be up to 5 years.The primary end point was in-stent late lumen loss at 9-month.Results Fifty patients (mean age (57.6±10.2) years) with 59 de novo long lesions (reference vessel diameter (2.85±0.44) mm,lesion length (35.2±9.4) mm,and stent length (41.8±11.3) mm) were enrolled.The angiographic follow-up rate was 92% at 9-month.The in-stent late loss was (0.16±0.16) mm.Proximal edge,distal edge and in-segment late loss (mm) were 0.21±0.35,0.03±0.33,and 0.07±0.26,respectively.No in-segment binary restenosis was observed.At 1-year no death,Q wave myocardial infarction (MI),or stent thrombosis occurred.Non-Q-wave MI occurred in two patients (4%) due to procedural complications.Conclusions Treatment of long coronary lesions with the FIREHAWK(R) stent is able to produce similar results as observed in the FIREHAWK(R) FIM clinical trial.Based on this result,we are confident in the treatment prospect of the FIREHAWK(R) for long coronary lesions.

  11. Urethralism concomitant with amphetamine abuse

    Directory of Open Access Journals (Sweden)

    Bang-Ping Jiann

    2014-09-01

    Full Text Available Urethralism is a paraphilia disorder in which a person exhibits the habitual self-insertion of a foreign body into the urethra to achieve sexual gratification. We report a patient who habitually inserted a foreign body into his urethra and abused amphetamines to cope with stress. A 48-year-old man presented at the emergency room because of urine leakage from the penile base. Prior to this incident, he had been admitted to hospital 10 times from 2000 to 2005 for the removal of foreign bodies from the lower urinary tract. The patient also reported repeatedly inhaling a high dose of amphetamine to reach a “high” status prior to inserting a foreign body into his urethra. After the successful removal of the foreign bodies, the patient was referred to a psychiatrist for management in coping with stress and illicit drug withdrawal. Psychiatric support and treatment appeared to have a beneficial effect on his sexual behavior. In the management of a case involving recurrent insertion of a foreign body into the lower urinary tract, clinicians should enquire about a history of drug abuse and consult the psychiatry department regarding stress management and drug abstinence.

  12. Localized urethral cancer in women

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, R.; Fowler, J.E. Jr.; Clayton, M.

    1987-10-01

    The results of treatments for localized carcinoma of the urethra were assessed in 21 consecutive women treated at our institutions over a twenty year period. Only one of the tumors was confined to the distal urethra. Eighty-six percent invaded the periurethral tissues and 24% were known to be associated with regional lymph node metastases. Fifty-seven percent were adenocarcinomas. Five patients refused active therapeutic intervention and expired within one to 30 months following diagnosis. Sixteen patients were treated with extirpative surgery, radiation therapy, or combinations of the two. Four are free of disease at one, four, eleven, and 15 years after treatment. Nine developed pelvic recurrences, two developed pelvic recurrences and distant metastases and one developed distant metastases only from six to 72 months (mean, 19 months) after initial treatment. Eight of these 12 patients died at two to 13 months (mean, 8 months) after secondary treatment, two are alive with residual pelvic tumor, and two are clinically free of disease at 7 and 48 months. Only six patients were known to have distant metastases at the time of death and five of these six had adenocarcinomas. Advanced localized urethral cancer in women is difficult to eradicate and usually fatal.

  13. Fabrication of balloon-expandable self-lock drug-eluting polycaprolactone stents using micro-injection molding and spray coating techniques.

    Science.gov (United States)

    Liu, Shih-Jung; Chiang, Fu-Jun; Hsiao, Chao-Ying; Kau, Yi-Chuan; Liu, Kuo-Sheng

    2010-10-01

    The purpose of this report was to develop novel balloon-expandable self-lock drug-eluting poly(ε-caprolactone) stents. To fabricate the biodegradable stents, polycaprolactone (PCL) components were first fabricated by a lab-scale micro-injection molded machine. They were then assembled and hot-spot welded into mesh-like stents of 3 and 5 mm in diameters. A special geometry of the components was designed to self-lock the assembled stents and to resist the external pressure of the blood vessels after being expanded by balloons. Characterization of the biodegradable PCL stents was carried out. PCL stents exhibited comparable mechanical property to that of metallic stents. No significant collapse pressure reduction and weight loss of the stents were observed after being submerged in PBS for 12 weeks. In addition, the developed stent was coated with paclitaxel by a spray coating technique and the release characteristic of the drug was determined by an in vitro elution method. The high-performance liquid chromatography analysis showed that the biodegradable stents could release a high concentration of paclitaxel for more than 60 days. By adopting the novel techniques, we will be able to fabricate biodegradable drug-eluting PCL stents of different sizes for various cardiovascular applications.

  14. Urethral Cancer Treatment (PDQ®)—Patient Version

    Science.gov (United States)

    Urethral cancer occurs in men and women and can spread quickly to lymph nodes near the urethra. Find out about risk factors, symptoms, tests to diagnose, prognosis, staging, and treatment for urethral cancer.

  15. The promise of urethral pressure reflectometry

    DEFF Research Database (Denmark)

    Khayyami, Yasmine; Klarskov, Niels; Lose, Gunnar

    2016-01-01

    pressure reflectometry (UPR), a method that measures pressure and the corresponding cross-sectional area along the entire length of the urethra continuously by means of acoustic reflectometry, have been performed. The studies have mainly been performed on patients with stress urinary incontinence (SUI......). METHODS: Our aim was to provide an overview of the studies conducted with UPR, establishing whether the method may be used in clinical practice. We reviewed all literature published on UPR. RESULTS: Urethral pressure reflectometry is easily performed with limited bother for the patient. The catheter...... measuring urethral pressure. UPR can discriminate patients with SUI from continent women and separate assessment of the sphincter function and support system is possible. Also, UPR has revealed statistically significant differences in urethral pressures after drug therapy for SUI. CONCLUSIONS: We conclude...

  16. 21 CFR 876.4590 - Interlocking urethral sound.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Interlocking urethral sound. 876.4590 Section 876...) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4590 Interlocking urethral sound. (a) Identification. An interlocking urethral sound is a device that consists of two metal sounds...

  17. Contemporary Management of Primary Distal Urethral Cancer.

    Science.gov (United States)

    Traboulsi, Samer L; Witjes, Johannes Alfred; Kassouf, Wassim

    2016-11-01

    Primary urethral cancer is one of the rare urologic tumors. Distal urethral tumors are usually less advanced at diagnosis compared with proximal tumors and have a good prognosis if treated appropriately. Low-stage distal tumors can be managed successfully with a surgical approach in men or radiation therapy in women. There are no clear-cut indications for the choice of the most appropriate treatment modality. Organ-preserving modalities have shown effective and should be used whenever they do not compromise the oncological safety to decrease the physical and psychological trauma of dismemberment or loss of sexual/urinary function. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Biodegradable Polymers

    OpenAIRE

    Isabelle Vroman; Lan Tighzert

    2013-01-01

    Biodegradable materials are used in packaging, agriculture, medicine and other areas. In recent years there has been an increase in interest in biodegradable polymers. Two classes of biodegradable polymers can be distinguished: synthetic or natural polymers. There are polymers produced from feedstocks derived either from petroleum resources (non renewable resources) or from biological resources (renewable resources). In general natural polymers offer fewer advantages than synthetic polymers. ...

  19. Biodegradable Polymers

    Directory of Open Access Journals (Sweden)

    Isabelle Vroman

    2009-04-01

    Full Text Available Biodegradable materials are used in packaging, agriculture, medicine and other areas. In recent years there has been an increase in interest in biodegradable polymers. Two classes of biodegradable polymers can be distinguished: synthetic or natural polymers. There are polymers produced from feedstocks derived either from petroleum resources (non renewable resources or from biological resources (renewable resources. In general natural polymers offer fewer advantages than synthetic polymers. The following review presents an overview of the different biodegradable polymers that are currently being used and their properties, as well as new developments in their synthesis and applications.

  20. Deferred endoscopic urethral realignment: Role in management of traumatic posterior urethral disruption

    Directory of Open Access Journals (Sweden)

    M.A. Elgammal

    2014-06-01

    Conclusion: When early realignment is postponed for any reason, deferred endoscopic realignment is considered an adequate substitute because urethral continuity can be achieved in a group of patients without increase incidence of impotence and incontinence.

  1. Role of metallic stents in benign esophageal stricture

    Science.gov (United States)

    Shim, Chan Sup

    2012-10-01

    Simple esophageal strictures, which are focal, straight, and large in diameter, usually require 1 - 3 dilation sessions to relieve symptoms. However, complex strictures, which are long, tortuous, or associated with a severely compromised luminal diameter, are usually more difficult to treat with conventional bougie or balloon dilation techniques, and often have high recurrence rates. Although the permanent placement of self-expandable metal stents (SEMS) has been used to manage refractory benign esophageal strictures, this procedure is associated with additional problems, such as stricture from tissue hyperplasia, stent migration, and fistula formation. Thus, several new types of stents have been developed, including temporary SEMS, self-expandable plastic stents (SEPS), and biodegradable stents. The use of these new products has produced varied results. Temporary SEMS that have been used to relieve benign esophageal conditions have caused granulation tissue at both ends of the stent because of contact between the mucosa and the exposed metal components of the stent, thus hindering stent removal. We examined the tissue response to two new types of SEMS, a flange-type and a straighttype, each coated with a silicone membrane on the outside of the metal mesh. These two SEMS were evaluated individually and compared with a conventional control stent in animal experiments. Although the newly designed stents resulted in reduced tissue hyperplasia, and were thus more easily separated from the esophageal tissue, some degree of tissue hyperplasia did occur. We suggest that newly designed DES (drug-eluting stents) may provide an alternative tool to manage refractory benign esophageal stricture.

  2. Advances in the Understanding and Treatment of Male Urethritis.

    Science.gov (United States)

    Bachmann, Laura H; Manhart, Lisa E; Martin, David H; Seña, Arlene C; Dimitrakoff, Jordan; Jensen, Jørgen Skov; Gaydos, Charlotte A

    2015-12-15

    Neisseria gonorrhoeae and Chlamydia trachomatis are well-documented urethral pathogens, and the literature supporting Mycoplasma genitalium as an etiology of urethritis is growing. Trichomonas vaginalis and viral pathogens (herpes simplex virus types 1 and 2 and adenovirus) can cause urethritis, particularly in specific subpopulations. New data are emerging regarding the potential role of bacterial vaginosis-associated bacteria in urethritis, although results are inconsistent regarding the pathogenic role of Ureaplasma urealyticum in men. Mycoplasma hominis and Ureaplasma parvum do not appear to be pathogens. Men with suspected urethritis should undergo evaluation to confirm urethral inflammation and etiologic cause. Although nucleic acid amplification testing would detect N. gonorrhoeae and C. trachomatis (or T. vaginalis if utilized), there is no US Food and Drug Administration-approved clinical test for M. genitalium available in the United States at this time. The varied etiologies of urethritis and lack of diagnostic options for some organisms present treatment challenges in the clinical setting.

  3. Urethral diverticulo-rectal fistula in AIDS.

    Science.gov (United States)

    Lee, W H; Yang, W J; Rha, K H; Chang, K H; Kim, J M; Lee, M S

    2001-10-01

    A 41-year-old heterosexual African man was evaluated for persistent urethral discharge, pneumaturia and watery diarrhea. Radiographic and endoscopic procedures established the diagnosis of a rectourethral fistula. The differential diagnosis of an acquired rectourethral fistula and the significance of AIDS are discussed.

  4. EAU guidelines on primary urethral carcinoma

    NARCIS (Netherlands)

    Gakis, G.; Witjes, J.A.; Comperat, E.; Cowan, N.C.; Santis, M. de; Lebret, T.; Ribal, M.J.; Sherif, A.M.

    2013-01-01

    CONTEXT: The European Association of Urology (EAU) Guidelines Group on Muscle-Invasive and Metastatic Bladder Cancer prepared these guidelines to deliver current evidence-based information on the diagnosis and treatment of patients with primary urethral carcinoma (UC). OBJECTIVE: To review the curre

  5. EAU guidelines on primary urethral carcinoma

    NARCIS (Netherlands)

    Gakis, G.; Witjes, J.A.; Comperat, E.; Cowan, N.C.; Santis, M. de; Lebret, T.; Ribal, M.J.; Sherif, A.M.

    2013-01-01

    CONTEXT: The European Association of Urology (EAU) Guidelines Group on Muscle-Invasive and Metastatic Bladder Cancer prepared these guidelines to deliver current evidence-based information on the diagnosis and treatment of patients with primary urethral carcinoma (UC). OBJECTIVE: To review the curre

  6. Incomplete urethral duplication in an adult male.

    LENUS (Irish Health Repository)

    Davis, N F

    2012-09-01

    Urethral duplication is a rare congenital anomaly with less than 200 cases reported. It predominantly occurs in males and is nearly always diagnosed in childhood or adolescence. It is defined as a complete second passage from the bladder to the dorsum of the penis or as an accessory pathway that ends blindly on the dorsal or ventral surface.

  7. Safety and efficacy of low-dose paclitaxel utilizing the cobra-P drug-eluting stent system with a novel biodegradable coating in de novo coronary lesions: The PLUS-ONE first-in-man study

    Energy Technology Data Exchange (ETDEWEB)

    Calderas, Carlos [Instituto de Clinicas Urologia Tamanaco, Caracas (Venezuela, Bolivarian Republic of); Condado, Jose Francisco; Condado, Jose Antonio [Hospital Centro Medico de Caracas y Hospital Miguel Perez Carreno, Caracas (Venezuela, Bolivarian Republic of); Flores, Alejandra [Instituto de Clinicas Urologia Tamanaco, Caracas (Venezuela, Bolivarian Republic of); Mueller, Amy; Thomas, Jack [Medlogics Device Corporation, Santa Rosa, CA (United States); Nakatani, Daisaku; Honda, Yasuhiro; Waseda, Katsuhisa [Stanford University, Stanford, CA (United States); Fitzgerald, Peter, E-mail: crci-cvmed@stanford.edu [Stanford University, Stanford, CA (United States)

    2014-01-15

    Background: The Cobra-P drug-eluting stent (DES) system consists of cobalt chromium alloy with bio-absorbable siloxane sol–gel matrix coating that elutes low dose paclitaxel within 6 months. The aim of this first-in-man trial was to evaluate the safety and performance of 2 doses of the Cobra-P DES. Methods: A total of 60 lesions (54 patients) were sequentially assigned to 2 different paclitaxel doses: group A (3.7 μg/18 mm, n = 30) or group B (8 μg/18 mm, n = 30). The primary endpoint was MACE at 4 months defined as cardiac death, myocardial infarction, and target lesion revascularization. Results: Patient and lesion characteristics were matched between the 2 groups except for male sex. MACE at 4 months was 3.3% and 0% respectively (P = 1.000) and at 1-year follow-up remained unchanged. In-stent late loss at 4 months was similar in both groups (0.36 ± 0.30 mm and 0.34 ± 0.20 mm P = .773). Conclusions: In this FIM study, implantation of the Cobra-P low dose paclitaxel-eluting stent with a bioabsorbable sol–gel coating was proven to be feasible and safe. Moderate neointimal proliferation was observed as well as an acceptable MACE rate up to 1 year.

  8. 生物可降解材料聚乳酸/聚羟基乙酸复合壳聚糖在人工冠状动脉血管支架制备中的应用%Artificial Coronary Vascular Stents Fabrication Using Biodegradable Material Compounds of PLA/PGA-co-Chitosan

    Institute of Scientific and Technical Information of China (English)

    郭清奎

    2012-01-01

    The first generation scaffolds of bare metal stents (BMS) and the second generation of drug eluting stents (DES) have been widely used in the treatment of coronary heart diseases. However, long term incidences of major adverse cardiovascular events and revascularization treatments are still high because of in-stent re-stenosis and thrombosis. These may be caused by chronic inflammations and vascular wall damages due to persistent metal stents stimulation. What's more, the eluting drugs within metal stents could also disturb normal growth of vascular endothelial cell, intima, tunica media, smooth muscle and epimysium. Therefore, in order to meet these demands several fully biodegradable scaffolds and drug carried stents have been manufactured using polymers polyester, polycarbonate and polyphosphate, etc. Among them, the security and histo-and hemo-compatibilities of coronary scaffolds made from poly-lactic acid (PLA), poly-glycolic acid (PGA), chitosan as coating, poly-caprolactone (PCL) and other copolymer like poly-lactic-co-glycolic acid (PLGA) have been testified to be sound. Nevertheless, there exist several different shortages for these stents such as tensile strength deficiency and slow degradation. PLA is hard and brittle with slow degradation, while PGA is soft with insufficient support force and fast degradation. Whether stents degrade too fast or too slow, they could not supply sufficient strength and effective support after implantation, and also they may cause target vascular injuries and elastic shrink inducing restenosis and thrombosis in long terms. Using optimized molar ratio component of PLA and PGA with chitosan coating, we can get sound composite materials with better biocompatibility, moderate degradation (approximately 3 - 6 months of complete degradation), adequate mechanical strength, lower inflammatory response and good range of extension, and establish an experiment ground for fully biodegradable vascular scaffolds fabrication.%第一代

  9. Coronary Stents: The Impact of Technological Advances on Clinical Outcomes.

    Science.gov (United States)

    Mennuni, Marco G; Pagnotta, Paolo A; Stefanini, Giulio G

    2016-02-01

    Percutaneous coronary interventions (PCI) were proposed in the late 1970s as an alternative to surgical coronary artery bypass grafting for the treatment of coronary artery disease. Important technological progress has been made since. Balloon angioplasty was replaced by bare metal stents, which allowed to permanently scaffold the coronary vessel avoiding acute recoil and abrupt occlusion. Thereafter, the introduction of early generation drug-eluting stents (DES) has significantly improved clinical outcomes, primarily by markedly reducing the risk of restenosis. New generation DES with thinner stent struts, novel durable or biodegradable polymer coatings, and new limus antiproliferative agents, have further improved upon the safety and efficacy profile of early generation DES. The present article aims to review the impact of technological advances on clinical outcomes in the field of PCI with coronary stents, and to provide a brief overview on clinical margins of improvement and unmet needs of available DES.

  10. Microscopy of Stained Urethral Smear in Male Urethritis; Which Cutoff Should be Used?

    Science.gov (United States)

    Moi, Harald; Hartgill, Usha; Skullerud, Kristin Helene; Reponen, Elina J; Syvertsen, Line; Moghaddam, Amir

    2017-03-01

    The microscopical diagnosis of male urethritis was recently questioned by Rietmeijer and Mettenbrink, lowering the diagnostic criteria of the diagnosis to ≥2 polymorphonuclear leucocytes (PMNL) per high power field (HPF), and adopted by Centers for Disease Control and Prevention in their 2015 STD Treatment Guidelines. The European Non-Gonococcal Urethritis Guideline advocates a limit of ≥5 PMNL/HPF. To determine if syndromic treatment of urethritis should be considered with a cutoff value of ≥2 PMNL/HPF in urethral smear. The design was a cross-sectional study investigating the presence and degree of urethritis relative to specific infections in men attending an STI clinic as drop-in patients. The material included 2 cohorts: a retrospective study of 13,295 men and a prospective controlled study including 356 men. We observed a mean chlamydia prevalence of 2.3% in the 0-9 stratum, and a 12-fold higher prevalence (27.3%) in the strata above 9. Of the chlamydia cases, 89.8% were diagnosed in strata above 9. For Mycoplasma genitalium, the prevalence was 1.4% in the 0-9 stratum and 11.2% in the stratum ≥10, and 83.6% were diagnosed in strata above 9. For gonorrhea, a significant increase in the prevalence occurred between the 0-30 strata and >30 strata from 0.2% to 20.7%. The results of the prospective study were similar. Our data do not support lowering the cutoff to ≥2 PMNL/HPF. However, a standardization of urethral smear microscopy seems to be impossible. The cutoff value should discriminate between low and high prevalence of chlamydia, mycoplasma, and gonorrhea to include as many as possible with a specific infection in syndromic treatment, without overtreating those with few PMNL/HPF and high possibility of having nonspecific or no urethritis.

  11. Drug release kinetics from a drug-eluting stent with asymmetrical coat

    DEFF Research Database (Denmark)

    Zhang, Haijun; Li, Xiaodong; Deng, Wei

    2017-01-01

    The aim of this study was to investigate the drug release profiles of biodegradable polymer sirolimus- or paclitaxel-eluting stents with asymmetrical coating (BPSES-A or BPPES-A) both in vitro and in vivo. In vitro, the drug release profile was characterized by measuring the drug concentration...... by HPLC over a time-course. In vivo, a porcine aorta stenting model was employed. The results showed that the drug release rates of BPSES-A and BPPES-A were slower, more stable and less burst releasing than those of conventionally coated stents (BPSES-C and BPPES-C respectively), both in vitro and in vivo...... demonstrated the effectiveness of both sirolimus and paclitaxel as stent coating agents, and revealed the favorable drug release kinetics and pharmacokinetics of asymmetrical coated stents compared with conventional coated stents....

  12. Repair and reconstruction of common bile duct by poly(lactide stent

    Directory of Open Access Journals (Sweden)

    Xiaoyi Xu

    2010-01-01

    Full Text Available To investigate the effect of repair of bioabsorbable poly(lactide (PLA biliary stent in common bile duct (CBD transection injury in canine prior to the clinical application. Circular tubing CBD stent was prepared by melt extraction technique using PLA. A transection incision was made on CBD of the normal canine, and then closed the incision with laser welding followed the implantation of PLA tubular stent into it. The stent was obtained to determine degradation of PLA in vivo at postoperative week 1, 4, and 12, respectively. The changes of outer diameter and burst pressure of CBD were investigated. Furthermore, serum liver enzyme values and CBD histopathological analysis were examined in the animals. The results noted that the polymer stent exhibited the same biomedical functions as T tubes and no significant tissue response. Therefore, biodegradable PLA stent matches the requirements in repair and reconstruction of CBD to support the duct, guide bile drainage and reduce T-tube-related complications.

  13. In vivo Evaluation of Cenderitide-Eluting Stent (CES) II.

    Science.gov (United States)

    Huang, Yingying; Ng, Xu Wen; Lim, Soon Ghim; Chen, Horng Haur; Burnett, John C; Boey, Yin Chiang Freddy; Venkatraman, Subbu S

    2016-02-01

    The use of drug-eluting coronary stents has led to significant reduction in in-stent restenosis (ISR), but led to delayed endothelialization, necessitating the prolonged use of expensive anti-thrombotic drugs with their side-effects. Cenderitide (CD-NP) is a novel anti-proliferative chimeric peptide of semi-endothelial origin. Our previous work in vitro has demonstrated; that the smooth muscle cells were inhibited significantly more than endothelial cells which is the desirable feature of an anti-restenosis drug. This work reports the effects of implantation of a centeritide-eluting stent (CES) on ISR and endothelialization in an in vivo model. CESs were produced by coating bare metallic stents with CD-NP entrapped in biodegradable poly(ε-caprolactone) using an ultrasonic spray coater. A total of 32 stents were successfully implanted into 16 pigs, and all animal survived for 28 days. The plasma levels of CD-NP were significantly higher in the CES group than in the control group (bare metal stents and polymer-coated stent) at post-stenting, indicating the successful release of CD-NP from the stent in vivo. Furthermore, SEM analysis results showed the greater endothelial coverage of the stent struts, as well as between the struts in CES group. Moreover, histological results showed mild inflammation, and low fibrin score at 28 days. However, plasma cGMP (second messenger, cyclic 3',5' guanosine monophosphate) does not show a significant difference, and the CES is also unable to show significant difference in terms on neointimal area and stenosis, in comparison to BMS at 28 days.

  14. Application of Rapamycin-Eluting Stent with Biodegradable Polymer Coating in Patients Receiving Emergency Percutaneous Coronary Intervention%生物可降解涂层雷帕霉素洗脱支架在老年急诊冠状动脉介入术中的疗效观察

    Institute of Scientific and Technical Information of China (English)

    杨静; 原家祥; 朱颖; 成颖

    2011-01-01

    目的 评价生物可降解涂层雷帕霉素洗脱(Excel)支架在老年急性ST段抬高型心肌梗死(STEMI)急诊冠状动脉介入(PCI)治疗中的临床疗效.方法 回顾性分析90例年龄≥65岁STEMI靶病变血管行急诊PCI治疗患者,术后联合应用抗血小板药氯吡格雷和阿司匹林6个月,其后单用阿司匹林,观察术后12个月主要不良心脏事件及复查冠状动脉造影判定支架再狭窄(ISR)的发生率.结果 90例患者中有89例成功置入Excel支架.30 d内心源性死亡1例,脑出血死亡1例.对于存活的87例患者随访12个月,主要不良心脏事件发生率为11.2%(10/89),无再发心肌梗死、血栓事件发生.87例患者行冠状动脉造影复查,支架内病变再狭窄率为10.3%(9/87).结论 Excel支架在老年STEMI 急诊PCI 的应用中有较好的临床疗效,术后6个月的两联(氯吡格雷和阿司匹林)抗血小板治疗是安全的.%Objective To evaluate the efficacy and safety of rapamycin - eluting stent with biodegradable polymer coating ( Excel stent ) in treating senile patients with ST - elevation myocardial infarction (STEMI) . Methods Ninety cases of elder patients with STEMI treated with emergency PCI were retrospectively reviewed. All these patients received combined clopidogrel and aspirin for 6 months followed by aspirin alone after pereutaneous coronary intervention ( PCI ) . Incidence rate of major adverse cardiovascular events ( MACE ) and in - stent restenosis ( ISR ) detected by coronary angiography during second visits were monitored for 12 months after PCI. Results PCI was successfully performed in 89 ( 98.8% ) patients. One case of cardiac death and one case of intracerehral hemorrhage death were observed within 30 days. Incidence rate of MACE was 11.2% ( 10/89 ) during the 12 months of follow - up among the remaining 87 discharged patients, with no recurrent acute myocardial infarction or thromboembolic event noted. Incidence rate of in - stent

  15. Improved bioresorbable microporous intravascular stents for gene therapy.

    Science.gov (United States)

    Ye, Y W; Landau, C; Meidell, R S; Willard, J E; Moskowitz, A; Aziz, S; Carlisle, E; Nelson, K; Eberhart, R C

    1996-01-01

    Drug imbibing microporous stents are under development at a number of centers to enhance healing of the arterial wall after balloon coronary angioplasty procedures. The authors improved the mechanical strength and reservoir properties of a biodegradable microporous stent reported to this Society in 1994. A combined tubular/helical coil stent is readily fabricated by flotation/precipitation and casting/ winding techniques. A two stage solvent swelling technique allows precise adjustment of the surface hydrophilic/hydrophobic balance. These developments permit seven-fold improvement in drug capacity without significantly altering mechanical properties. Stents modified in this manner retain tensile and compressive strength and are suitable for remote deployment. Elution kinetics of these modified stents suggest they are suitable for gene delivery. Successful gene transfer and transmural expression have been demonstrated after implantation of stents impregnated with a recombinant adenovirus carrying a nuclear localizing beta-galactosidase reporter gene into rabbit carotid arteries. These studies suggest that surface modified, bioresorbable polymer stents ultimately may be useful adjunctive devices for gene transfer during percutaneous transluminal revascularization.

  16. Urethral anatomy and semen flow during ejaculation

    Science.gov (United States)

    Kelly, Diane

    2016-11-01

    Ejaculation is critical for reproductive success in many animals, but little is known about its hydrodynamics. In mammals, ejaculation pushes semen along the length of the penis through the urethra. Although the urethra also carries urine during micturition, the flow dynamics of micturition and ejaculation differ: semen is more viscous than urine, and the pressure that drives its flow is derived primarily from the rhythmic contractions of muscles at the base of the penis, which produce pulsatile rather than steady flow. In contrast, Johnston et al. (2014) describe a steady flow of semen through the crocodilian urethral groove during ejaculation. Anatomical differences of tissues associated with mammalian and crocodilian urethral structures may underlie these differences in flow behavior.

  17. Acupuncture Treatment of Female Urethral Syndrome

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yuan; HE Jia-yang; WANG Si-you

    2003-01-01

    Purpose To observe the curative effect of acupuncture on female urethral syndrome. Method A treatment group of 30 patients were treated with acupuncture at points Zhongji ( CV 3 ), Zusanli ( ST 36), Sanyinjiao ( SP 6), Shenshu ( BL 23 ), Pangguangshu ( BL28), Guanyuan (CV 4), Zhaohai (KI 6) and Zhonglushu ( BL 29). A control group of 28 patients were treated with capsule Norfloxacini and capsule Cystocaps.Results Of the treatment group, 26 patients had effectiveness and 4 had ineffectiveness; of the control group,2 patients had effectiveness and 26 had ineffectiveness.There was a significant difference in effective rate between the two groups (P<0.01). Conclusion The curative effect of acupuncture on female urethral syndrome is better than that of routine treatment.

  18. EAU guidelines on primary urethral carcinoma.

    Science.gov (United States)

    Gakis, Georgios; Witjes, J Alfred; Compérat, Eva; Cowan, Nigel C; De Santis, Maria; Lebret, Thierry; Ribal, Maria J; Sherif, Amir M

    2013-11-01

    The European Association of Urology (EAU) Guidelines Group on Muscle-Invasive and Metastatic Bladder Cancer prepared these guidelines to deliver current evidence-based information on the diagnosis and treatment of patients with primary urethral carcinoma (UC). To review the current literature on the diagnosis and treatment of patients with primary UC and assess its level of scientific evidence. A systematic literature search was performed to identify studies reporting urethral malignancies. Medline was searched using the controlled vocabulary of the Medical Subject Headings database, along with a free-text protocol. Primary UC is considered a rare cancer, accounting for EAU. It aims to increase awareness in the urologic community and provide scientific transparency to improve outcomes of this rare urogenital malignancy. Copyright © 2013 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  19. Neoatherosclerosis in the stent

    Directory of Open Access Journals (Sweden)

    A. A. Komkov

    2015-01-01

    Full Text Available Achievements of interventional cardiology in the treatment of coronary artery disease are based on coronary balloon angioplasty with implanting bare metal stents and drug eluting stents. Questions of complications such as early stent thrombosis and restenosis of stent were solved in a considerable degree. However, with the lengthening of the followup period, the problem of late complications became obvious. Except endothelization and fibromuscular proliferation in stented coronary arteries the process of plaque formation has an important influence on later complications in follow-up period more than one year. This process was defined as neoatherosclerosis. This is verified by clinical manifestations of the disease, histological studies, angioscopy, intravascular ultrasound and optical-coherence tomography in stented patients. Dynamic observation of the condition in stentedcoronary arteries showed multistep proliferation with restenosis, its regression, and neoatherosclerosis development. Evidences of neoatherosclerosis formation in stented coronary arteries are considered in this review.

  20. Female urethral syndrome. A female prostatitis?

    OpenAIRE

    1996-01-01

    The cause of the female urethral syndrome has previously been obscure, as it has been associated by definition with a lack of objective findings but a plethora of subjective complaints of retropubic pressure, dyspareunia, urinary frequency, and dysuria. There is now strong evidence that the microscopic paraurethral glands connected to the distal third of the urethra in the prevaginal space are homologous to the prostate. They stain histologically for prostate-specific antigen and, like the pr...

  1. Urethral strictures incident to bicycle motocross racing.

    Science.gov (United States)

    Delaney, Daniel P; Carr, Michael C

    2005-04-01

    A dramatic shift from traditional team to alternative or "extreme" sports has given rise to a new generation of nontraditional athletes and sports-related injuries in the pediatric population. We present a case of 2 brothers who developed urethral strictures believed incident to BMX racing. We address current demographics and the general presentation and course of treatment to aid both the pediatric urologist and the general practitioner in prompt and proper diagnosis.

  2. Electroacupuncture Treatment of 36 Patients with Female Urethral Syndrome

    Institute of Scientific and Technical Information of China (English)

    LIU Lian; WANG Xiao-ming; WANG Si-you

    2003-01-01

    Purpose: To investigate a treatment for female urethral syndrome. Method: Electroacupuncture was used to treat 36 cases of female urethral syndrome,with medication for 42 cases as a control. Results: The total effective rate was 88.9% from electroacupuncture and 52.4% from medication. There was a significant difference in curative effect between the two groups (p<0.05). Conclusion: Electroacupuncture is an effective method for treatment of female urethral syndrome.

  3. Fabrication, Crosslinking and in vitro Biocompatibility of a Novel Degradable Nano-structure Urethral Tubular Scaffold

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-qing; WANG Chun-xi; CHEN Qi-hui; HOU Yu-chuan; LU Zhi-hua; HU Jing-hai; ZHANG Hai-feng; HAO Yuan-yuan; ZHANG Long; GAO Zhan-tuan

    2012-01-01

    A degradable poly(lactic-co-glycolic acid,LA∶GA=80∶20)(PLGA) urethral tubular scaffold was fabricated by electrospinning.In order to enhance the mechanical properties,the scaffold was crosslinked with glutaraldehyde.The structure and properties of the crosslinked scaffolds were investigated by the mechanical property testing,scanning electron microscopy(SEM),degradability test in vitro and 3-(4,5)-dimethylthiahiazo(-z-yl)-3,5-diphenytetrazoliumromide(MTT).The results show that the scaffold has the nano-structure.The pore size and the porosity are suitable for cell seeding,growth and extracellular matrix production.Although influenced by the crosslinking slightly,the pore size and the porosity could still support cell proliferation and tissuse formation.The mechanical properties are remarkably increased by the crosslinking of glutaraldehyde,and it could meet the demands of a urethral stent.The scaffold could completely collapse within 70 d.The results of the biocompatibility test show that the PLGA scaffold had no cytotoxicity.

  4. [Clinical practice guideline. Traumatic urethral stenosis in males].

    Science.gov (United States)

    Serrano-Brambila, Eduardo Alonso; Moreno-Alcázar, Othón Martino; Neri-Páez, Edgar; Sánchez-Martínez, Luis Carlos; Hernández-Ordóñez, Octavio Francisco; Morales-Morales, Arturo; Basavilvazo-Rodríguez, M Antonia; Torres-Arreola, Laura del Pilar; Valenzuela-Flores, Adriana Abigail; Hernández-Valencia, Marcelino

    2013-01-01

    The incidence of urethral stenosis in Mexico had not been documented. At the Centro Médico Nacional La Raza, during the year 2010, 629 patients with urethral stenosis were attended as outpatient consultation: 85 % with previous urethral stenosis and 15 % with urethral treatment complication. Urethral stenosis is a chronic illness, with multiple etiological origins and the handling is controversial. It has a great negative impact for the patients and the recurrence reaches 85 %. The treatment consisted of an invasive approach (urethral dilations, endoscopy procedure) and open surgery (urethroplasty). The World Health Organization and World Alliance take the world challenge about the urinary tract infections associated with the attention of patients, focused on urethral stenosis. The objective of the following clinical guide is to offer to the health professional a clinical tool for making decisions in the handling of the hardship or masculine urethral stenosis, based on the best available evidence, carrying out in systematized form with bibliographical research using validated terms of the MeSH: urethral structures, in the databases Trip database, PubMed, Guideline Clearinghouse, Cochrane Library and Ovid.

  5. The urethral closure function in continent and stress urinary incontinent women assessed by urethral pressure reflectometry.

    Science.gov (United States)

    Saaby, Marie-Louise

    2014-02-01

    Stress urinary incontinence (SUI) occurs when the bladder pressure exceeds the urethral pressure in connection with physical effort or exertion or when sneezing or coughing and depends both on the strength of the urethral closure function and the abdominal pressure to which it is subjected. The urethral closure function in continent women and the dysfunction causing SUI are not known in details. The currently accepted view is based on the concept of a sphincteric unit and a support system. Our incomplete knowledge relates to the complexity of the closure apparatus and to inadequate assessment methods which so far have not provided robust urodynamic diagnostic tools, severity measures, or parameters to assess outcome after intervention. Urethral Pressure Reflectometry (UPR) is a novel method that measures the urethral pressure and cross-sectional area (by use of sound waves) simultaneously. The technique involves insertion of only a small, light and flexible polyurethane bag in the urethra and therefore avoids the common artifacts encountered with conventional methods. The UPR parameters can be obtained at a specific site of the urethra, e.g. the high pressure zone, and during various circumstances, i.e. resting and squeezing. During the study period, we advanced the UPR technique to enable faster measurement (within 7 seconds by the continuous technique) which allowed assessment during increased intra-abdominal pressure induced by physical straining. We investigated the urethral closure function in continent and SUI women during resting and straining by the "fast" UPR technique. Thereby new promising urethral parameters were provided that allowed characterization of the closure function based on the permanent closure forces (primarily generated by the sphincteric unit, measured by the Po-rest) and the adjunctive closure forces (primarily generated by the support system, measured by the abdominal to urethral pressure impact ratio (APIR)). The new parameters enabled

  6. Transurethral exchange of double-J ureteral stent using goose- neck snare

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Chang Ho; Kim, Yun Hwan; Cho, Sung Bum; Kim, Chul Joong; Kim, Hyoung Rae; Kim, Hong Weon; Suh, Won Hyuck [College of Medicine, Korea University, Seoul (Korea, Republic of); Cho, Sung Bum [Eulji Hospital, Eulji College of Medicine, Taejon (Korea, Republic of)

    2000-09-01

    To evaluate the usefulness of transurethral exchange of double-J ureteral stent as an effective alternative to the cystoscopic approach. There were 20 exchange cases involving seven patients (six women and one man) who initially underwent anterograde manipulation of a double-J ureteral stent. Indications for stent placement were ureteral stricture caused by malignancy in six patients (cervical carcinoma (n=3D5), stomach carcinoma (n=3D1)), and renal tuberculosis in one. An 8-F Nelaton catheter was inserted in the bladder via the urethra and contrast material was injected until the bladder was fully distended. The distal end of a double-J ureteral stent was extracted to the urethral orifice using a goose-neck snare and a 0.035{sup s}tiff guide wire was then advanced to the renal pelvis through the stent. After that, the stent was removed and a 4-F Cobra catheter was advanced to the renal pelvis along the guide wire. Contrast material was injected through the catheter, and the renal pelvis, calyx and ureter were opacified. The 0.035 stiff guide wire was again inserted via the catheter, and a new double-J ureteral stent was inserted, and the catheter removed. Finally, the new double-J stent was properly located within the renal pelvis and the bladder. Double-J ureteral stents were successfully exchanged in 19 of 20 exchange cases. After the procedure, all patients reported tolerable, minimal lower abdominal pain. Transurethral exchange of double-J ureteral stent is a useful alternative to cystoscopy. (author)

  7. Reconstruction of rabbit urethra using urethral extracellular matrix

    Institute of Scientific and Technical Information of China (English)

    杨嗣星; 姚颐; 胡云飞; 宋超; 王玲珑; 金化民

    2004-01-01

    Background Urethral reconstruction for both congenital and acquired etiologies remains a challenge for most urologic surgeons. Tissue engineering has been proposed as a strategy for urethral reconstruction. The purpose of This study was to determine whether a naturally derived extracellular matrix substitute developed for urethral reconstruction would be suitable for urethral repair in an animal model.Methods A urethral segmental defect was created in 20 male rabbits. The urethral extracellular matrix, obtained and processed from rabbit urethral tissue, was trimmed and transplanted to repair the urethral defect. Then, the regenerated segment was studied histologically by haematoxylin-eosin staining and Van Gieson staining at 10 days, 3 weeks, 6 weeks, and 24 weeks postoperation. Retrograde urethrography was used to evaluate the function of the regenerated urethras of 4 rabbits 10 and 24 weeks after the operation. The urodynamics of 4 rabbits from the experimental group and control group Ⅰ were assessed and compared. In addition, 4 experimental group rabbits were examined by a urethroscope 24 weeks after the operation.Results At 10 days after operation, epithelial cells had migrated from each side, and small vessels were observed in the extracellular matrix. The matrix and adjacent areas of the host tissue were infiltrated with inflammatory cells. The epithelium covered the extracellular matrix fully at 3 weeks postoperation. Well-formed smooth-muscle cells were first confirmed after 6 weeks, at which point the inflammatory cells had disappeared. At 24 weeks postoperation, the regenerated tissue was equivalent to the normal urethra. Urethrography and urodynamic evaluations showed that there was no difference between normal tissue and regenerated tissue.Conclusions Urethral extracellular matrix appears to be a useful material for urethral repair in rabbits. The matrix can be processed easily and has good characteristics for tissue handling and urethral function.

  8. Auxetic coronary stent endoprosthesis

    DEFF Research Database (Denmark)

    Amin, Faisal; Ali, Murtaza Najabat; Ansari, Umar;

    2014-01-01

    BACKGROUND: Cardiovascular heart disease is one of the leading health issues in the present era and requires considerable health care resources to prevent it. The present study was focused on the development of a new coronary stent based on novel auxetic geometry which enables the stent to exhibit...... a negative Poisson's ratio. Commercially available coronary stents have isotropic properties, whereas the vascular system of the body shows anisotropic characteristics. This results in a mismatch between anisotropic-isotropic properties of the stent and arterial wall, and this in turn is not favorable...... for mechanical adhesion of the commercially available coronary stents with the arterial wall. It is believed that an auxetic coronary stent with inherent anisotropic mechanical properties and negative Poisson's ratio will have good mechanical adhesion with the arterial wall. METHODS: The auxetic design...

  9. Possible Role of Large Fluid Intake in Delaying Formation of Encrustations and, thereby, Prolonging Working Life of Memokath Stent for Nearly 14 Years in a Spinal Cord Injury Patient

    Directory of Open Access Journals (Sweden)

    Subramanian Vaidyanathan

    2007-01-01

    Full Text Available The Memokath stent has been used in spinal cord injury patients as a reversible alternative to external urethral sphincterotomy, but the stent has a finite lifetime of <2 years before failure in the majority of patients. We report an unusual case of a spinal cord injury patient in whom memokath stent was functioning for almost 14 years. The long life span of the Memokath in this patient was probably due to this person's habit of drinking around 5 l of fluids a day. Large fluid intake resulted in high urine output and, consequently, deceased the risk of urine infections and delayed formation of encrustations around the stent. Although this case represents an unusual length of time for a Memokath stent to have been in place and functioning, caution should be exercised against the long-term use of Memokath stents. Memokath stents do not get absorbed into the mucosa unlike urolume stents and, therefore, are prone to stone formation. Further, Memokath stents have not yet been approved in the U.S. either for bladder outlet obstruction or detrusor-sphincter dyssynergia. This case is also a reminder to health professionals that if a tetraplegic patient, in whom a Memokath stent has been deployed for treatment of detrusor-sphincter dyssynergia, presents with autonomic dysreflexia, encrustations blocking the lumen of the stent or calculus formation around the stent should be considered as possible reasons for autonomic dysreflexia.

  10. Computational Bench Testing to Evaluate the Short-Term Mechanical Performance of a Polymeric Stent.

    Science.gov (United States)

    Bobel, A C; Petisco, S; Sarasua, J R; Wang, W; McHugh, P E

    2015-12-01

    Over the last decade, there has been a significant volume of research focussed on the utilization of biodegradable polymers such as poly-L-lactide-acid (PLLA) for applications associated with cardiovascular disease. More specifically, there has been an emphasis on upgrading current clinical shortfalls experienced with conventional bare metal stents and drug eluting stents. One such approach, the adaption of fully formed polymeric stents has led to a small number of products being commercialized. Unfortunately, these products are still in their market infancy, meaning there is a clear non-occurrence of long term data which can support their mechanical performance in vivo. Moreover, the load carry capacity and other mechanical properties essential to a fully optimized polymeric stent are difficult, timely and costly to establish. With the aim of compiling rapid and representative performance data for specific stent geometries, materials and designs, in addition to reducing experimental timeframes, Computational bench testing via finite element analysis (FEA) offers itself as a very powerful tool. On this basis, the research presented in this paper is concentrated on the finite element simulation of the mechanical performance of PLLA, which is a fully biodegradable polymer, in the stent application, using a non-linear viscous material model. Three physical stent geometries, typically used for fully polymeric stents, are selected, and a comparative study is performed in relation to their short-term mechanical performance, with the aid of experimental data. From the simulated output results, an informed understanding can be established in relation to radial strength, flexibility and longitudinal resistance, that can be compared with conventional permanent metal stent functionality, and the results show that it is indeed possible to generate a PLLA stent with comparable and sufficient mechanical performance. The paper also demonstrates the attractiveness of FEA as a tool

  11. In vitro hemocompatibility and cytocompatibility of dexamethasone-eluting PLGA stent coatings

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiang; Liu, Yang; Luo, Rifang; Chen, Si; Li, Xin; Yuan, Shuheng; Wang, Jin, E-mail: jinxxwang@263.net; Huang, Nan

    2015-02-15

    Highlights: • Biodegradable dexamethasone-eluting PLGA stent coatings were developed. • Stent coatings can withstand the compressive and tensile strains without cracking. • Stent coatings presented favorable release kinetic for the lesion site. • Stent coatings can effectively inhibit the adhesion and activation of platelets. • Stent coatings can effectively inhibit the proliferation of SMC. - Abstract: Drug-eluting stents (DESs) have been an important breakthrough for interventional cardiology applications since 2002. Though successful in reducing restenosis, some adverse clinical problems still emerged, which were mostly caused by the bare-metal stents and non-biodegradable polymer coatings, associated with the delayed endothelialization process. In this study, dexamethasone-loaded poly (lactic-co-glycolic acid) (PLGA) coatings were developed to explore the potential application of dexamethasone-eluting stents. Dexamethasone-eluting PLGA stents were prepared using ultrasonic atomization spray method. For other tests like stability and cytocompatibility and hemocompatibility tests, dexamethasone loaded coatings were deposited on 316L SS wafers. Fourier transform-infrared spectroscopy (FT-IR) results demonstrated that there was no chemical reaction between PLGA and dexamethasone. The balloon expansion experiment and surface morphology observation suggested that the stent coatings were smooth and uniform, and could also withstand the compressive and tensile strains imparted without cracking after stent expansion. The drug release behavior in vitro indicated that dexamethasone existed burst release within 1 day, but it presented linear release characteristics after 6 days. In vitro platelets adhesion, activation test and APTT test were also done, which showed that after blending dexamethasone into PLGA, the hemocompatibility was improved. Besides, dexamethasone and dexamethasone-loaded PLGA coatings could significantly inhibit the attachment and

  12. A rare case of congenital Y-type urethral duplication

    Directory of Open Access Journals (Sweden)

    Charu Tiwari

    2015-11-01

    Full Text Available Duplication of urethra is a rare congenital anomaly. We report a case of Y-type of urethral duplication with the accessory urethra arising from posterior urethra and opening in the perineum. The orthotopic urethra was normal. The accessory urethral tract was cored, transfixed and divided. At 1 year of follow-up, the patient has no urinary complaints

  13. Transurethral incision of urethral diverticulum in the female

    DEFF Research Database (Denmark)

    Miskowiak, J; Honnens de Lichtenberg, M

    1989-01-01

    A new technique of transurethral incision of urethral diverticulum was successfully used in two women. The method described is safe, simple and shortens operating time.......A new technique of transurethral incision of urethral diverticulum was successfully used in two women. The method described is safe, simple and shortens operating time....

  14. Anterior urethral recurrence of superficial bladder cancer: its clinical significance.

    Directory of Open Access Journals (Sweden)

    Saika T

    2003-12-01

    Full Text Available The aim of this study was to reveal the clinical features of anterior urethral recurrence in patients with superficial bladder cancer, and to determine the appropriate treatment. Three hundred and three patients with superficial bladder cancer, who were newly diagnosed and initially treated conservatively in our hospital between 1965 and 1990, were followed for at least 5 years and their clinical outcomes were analyzed. Clinical factors, including anterior urethral recurrence, were evaluated statistically regarding tumor progression. Eight patients (2.6% had anterior urethral recurrence following superficial bladder cancer. Twenty-four patients (7.9% had tumor progression and 149 (49.2% had tumor recurrence. In a multivariate analysis using a logistic model, anterior urethral recurrence was the most important factor, followed by histological grade. Four of 5 patients who were treated for anterior urethral recurrent tumors by transurethral resection showed progression and died of the cancer within one year. Two of the remaining three patients who underwent radical cysto-urethrectomy at the time of anterior urethral recurrence survived. Anterior urethral recurrence following superficial bladder cancer is a predictor for rapid subsequent malignant progression. Once there is anterior urethral recurrence, radical intensive therapy, including radical cysto-urethrectomy, should be carried out immediately.

  15. Fiber types in the striated urethral and anal sphincters

    DEFF Research Database (Denmark)

    Schrøder, H D; Reske-Nielsen, E

    1983-01-01

    Seven normal human striated urethral and anal sphincters obtained by autopsy were examined using histochemical techniques. In both the urethral sphincter and the subcutaneous (s.c.) and superficial part of the anal sphincter a characteristic pattern with two populations of muscle fibers, abundant...... contractions and to react in stress conditions with fast increase in tension....

  16. Penile shaft sinus: A sequalae of circumcision in urethral duplication

    Directory of Open Access Journals (Sweden)

    Lukman O Abdur-Rahman

    2009-01-01

    Full Text Available Urethral duplication (UD is rare congenital anomalies with varied presentation. Careful clinical evaluation of children by specialist would enhance diagnosis, adequate management and reduce occurrence of complication. We present a 12-year-old boy with chronic post circumcision ventral penile sinus that was successfully managed for urethral duplication.

  17. Emerging technologies: Polymer-free phospholipid encapsulated sirolimus nanocarriers for the controlled release of drug from a stent-plus-balloon or a stand-alone balloon catheter

    NARCIS (Netherlands)

    P.A. Lemos Neto (Pedro); V. Farooq (Vasim); C.K. Takimura (Celso); P.S. Gutierrez (Paulo); R. Virmani (Renu); F. Kolodgie (Frank); U. Christians (Uwe); A.N. Kharlamov (Alexander ); M. Doshi (Manish); P. Sojitra (Prakash); H.M.M. van Beusekom (Heleen); P.W.J.C. Serruys (Patrick)

    2013-01-01

    textabstractDrug-eluting stents have proven to be effective in reducing the risk of late restenosis. In order to achieve a controlled and prolonged release of the antiproliferative agent, current drug-eluting stents utilise various biodegradable as well as non-erodible polymeric blends to coat the s

  18. Degradation and antibacterial properties of magnesium alloys in artificial urine for potential resorbable ureteral stent applications.

    Science.gov (United States)

    Lock, Jaclyn Y; Wyatt, Eric; Upadhyayula, Srigokul; Whall, Andrew; Nuñez, Vicente; Vullev, Valentine I; Liu, Huinan

    2014-03-01

    This article presents an investigation on the effectiveness of magnesium and its alloys as a novel class of antibacterial and biodegradable materials for ureteral stent applications. Magnesium is a lightweight and biodegradable metallic material with beneficial properties for use in medical devices. Ureteral stent is one such example of a medical device that is widely used to treat ureteral canal blockages clinically. The bacterial colony formation coupled with the encrustation on the stent surface from extended use often leads to clinical complications and contributes to the failure of indwelling medical devices. We demonstrated that magnesium alloys decreased Escherichia coli viability and reduced the colony forming units over a 3-day incubation period in an artificial urine (AU) solution when compared with currently used commercial polyurethane stent. Moreover, the magnesium degradation resulted in alkaline pH and increased magnesium ion concentration in the AU solution. The antibacterial and degradation properties support the potential use of magnesium-based materials for next-generation ureteral stents. Further studies are needed for clinical translation of biodegradable metallic ureteral stents.

  19. Urethral catheter knotting: an avoidable complication

    Directory of Open Access Journals (Sweden)

    Ismail Burud

    2013-03-01

    Full Text Available Urethral catheterisation is a common andsafe procedure performed routinely. The small sizeof the urethra in a child necessitates the use of aninfant feeding tube (Size 5 to 8 F for catheterisation.Knotting within the bladder is a rare complication withsignificant morbidity often necessitating surgical orendoscopic removal. Insertion of an excessive lengthof tube contributes to coiling and knotting. We reportan instance of knotting of an infant feeding tube inthe proximal penile urethra of a 4 year-old male childrequiring urethrotomy to remove it. Awareness of therisk and proper technique can reduce this complication.

  20. Urethral catheters: can we reduce use?

    Directory of Open Access Journals (Sweden)

    van den Akker-van Marle M Elske

    2011-05-01

    Full Text Available Abstract Background Indwelling urinary catheters are the main cause of healthcare-associated urinary tract infections. It can be expected that reduction of the use of urinary catheters will lead to decreased numbers of urinary tract infection. Methods The efficacy of an intervention programme to improve adherence to recommendations to reduce the use of urethral catheters was studied in a before-after comparison in ten Dutch hospitals. The programme detected barriers and facilitators and each individual facility was supported with developing their own intervention strategy. Outcome was evaluated by the prevalence of catheters, alternatives such as diapers, numbers of urinary tract infections, the percentage of correct indications and the duration of catheterization. The costs of the implementation as well as the catheterization were evaluated. Results Of a population of 16,495 hospitalized patients 3335 patients of whom 2943 were evaluable for the study, had a urethral catheter. The prevalence of urethral catheters decreased insignificantly in neurology (OR 0.93; 95% CI 0.77 - 1.13 and internal medicine wards (OR 0.97; 95% CI 0.83 - 1.13, decreased significantly in surgical wards (OR 0.84; 95% CI 0.75 - 0.96, but increased significantly in intensive care (IC and coronary care (CC units (OR 1.48; 95% CI 1.01 - 2.17. The use of alternatives was limited and remained so after the intervention. Duration of catheterization decreased insignificantly in IC/CC units (ratio after/before 0.95; 95% CI 0.78 - 1.16 and neurology (ratio 0.97; 95% CI 0.80 - 1.18 and significantly in internal medicine (ratio 0.81; 95% CI 0.69 - 0.96 and surgery wards (ratio 0.80; 95% CI 0.71 - 0.90. The percentage of correct indications on the day of inclusion increased from 50 to 67% (p Conclusion Targeted implementation of recommendations from an existing guideline can lead to better adherence and cost savings. Especially, hospitals which use a lot of urethral catheters or

  1. Haemophilus parainfluenzae urethritis among homosexual men.

    Science.gov (United States)

    Hsu, Meng-Shiuan; Wu, Mei-Yu; Lin, Tsui-Hsien; Liao, Chun-Hsing

    2015-08-01

    Haemophilus parainfluenzae is a common inhabitant of the human upper respiratory tract of the normal oral microflora. We report three men who had been having unprotected sex with men (MSM) and subsequently acquired H. parainfluenzae urethritis, which was confirmed by 16S rRNA gene sequencing analysis. Two men were treated with ceftriaxone and doxycycline, and the third man was treated with clarithromycin. All three patients responded to treatment. This case series highlights the potential role of H. parainfluenzae as a sexually transmitted genitourinary pathogen.

  2. Evaluation of the Anti-migration Effect of Barbed Prostatic Stents: In Vitro Study in Urethra-mimicking Bovine Pericardium Phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Na, Han Kyu, E-mail: hankyu1324@empas.com; Song, Ho-Young, E-mail: hysong@amc.seoul.kr; Kim, Jin Hyoung, E-mail: m1fenew@hanmail.net [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center (Korea, Republic of); Nam, Deok Ho, E-mail: namjindan@paran.com [Kyung Hee University Hospital at Gangdong, School of Medicine, Kyung Hee University, Department of Radiology (Korea, Republic of); Park, Jung-Hoon, E-mail: jhparkz@amc.seoul.kr [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center (Korea, Republic of); Jeong, In Gab, E-mail: uroman2000@yahoo.co.kr; Kim, Choung-Soo, E-mail: cskim@amc.seoul.kr [University of Ulsan College of Medicine, Department of Urology, Asan Medical Center (Korea, Republic of)

    2013-02-15

    This study was designed to compare the migration rates of covered stents with eight, four, and zero barbs in urethra-mimicking bovine pericardium models. Three types of polytetrafluoroethylene-covered retrievable self-expandable prostatic stents, with eight, four, and zero barbs, were tested in bovine pericardium models, consisting of normal saline-filled acrylic containers with tubes at both ends and a replica of the human urethra. The barbs were 2 mm in length and projected 60 Degree-Sign toward the urinary bladder. The anti-migration force (AMF) and resistance force against stent removal (RFSR) were measured by an automatic push-pull gauge system at a fixed rate (2 mm/s). Significant differences in AMF among the three stent types were detected (P < 0.001). Median AMF was far greater for eight-barbed than for four-barbed stents (11.96 vs. 7.55 N, P = 0.003). For stent removal, the difference between 4- and 8-barbed stents were not significant in median static (5.54 vs. 6.08 N, P = 0.15) or sliding (prostatic urethra, 5.32 vs. 5.59 N, P = 0.65; membranous urethra, 7.78 vs. 8.57 N, P = 0.364) RFSR. No perforations or scratched traces were observed during removal of these stents. The inclusion of eight barbs projecting 60 Degree-Sign toward the urinary bladder were not only effective against stent migration in this model but suggests that these stents may be suitable for the treatment of prostatic urethral strictures without severely irritating the tissue. However, whether these results translate into living urethral tissue is unclear, necessitating further studies.

  3. Oil biodegradation

    NARCIS (Netherlands)

    Rahsepar, Shokouhalsadat; Langenhoff, Alette A.M.; Smit, Martijn P.J.; Eenennaam, van Justine S.; Murk, Tinka; Rijnaarts, Huub H.M.

    2017-01-01

    During the Deepwater Horizon (DwH) oil spill, interactions between oil, clay particles and marine snow lead to the formation of aggregates. Interactions between these components play an important, but yet not well understood, role in biodegradation of oil in the ocean water. The aim of this study

  4. Comparing coronary stent material performance on a common geometric platform through simulated bench testing.

    Science.gov (United States)

    Grogan, J A; Leen, S B; McHugh, P E

    2012-08-01

    Absorbable metallic stents (AMSs) are a newly emerging cardiovascular technology which has the potential to eliminate long-term patient health risks associated with conventional permanent stents. AMSs developed to date have consisted of magnesium alloys or iron, materials with inferior mechanical properties to those used in permanent stents, such as stainless steel and cobalt-chromium alloys. However, for AMSs to be feasible for widespread clinical use it is important that their performance is comparable to modern permanent stents. To date, the performances of magnesium, iron, and permanent stent materials have not been compared on a common stent platform for a range of stent performance metrics, such as flexibility, radial strength, and recoil. In this study, this comparison is made through simulated bench testing, based on finite-element modelling. The significance of this study is that it allows potential limitations in current AMS performance to be identified, which will aid in focusing future AMS design. This study also allows the identification of limitations in current AMS materials, thereby informing the on-going development of candidate biodegradable alloys. The results indicate that the AMSs studied here can match the recoil characteristics and radial strength of modern permanent stents; however, to achieve this, larger strut dimensions are required. It is also predicted that the AMSs studied are inferior to permanent stents in terms of maximum absolute curvature and longitudinal stiffness.

  5. The role of stents in the treatment of congenital heart disease: Current status and future perspectives

    Directory of Open Access Journals (Sweden)

    Peters Bjoern

    2009-01-01

    Full Text Available Intravascular or intracardiac stenoses occur in many forms of congenital heart disease (CHD. Therefore, the implantation of stents has become an accepted interventional procedure for stenotic lesions in pediatric cardiology. Furthermore, stents are know to be used to exclude vessel aneurysm or to ensure patency of existing or newly created intracardiac communications. With the further refinement of the first generation of devices, a variety of "modern" stents with different design characteristics have evolved. Despite the tremendous technical improvement over the last 20 years, the "ideal stent" has not yet been developed. Therefore, the pediatric interventionalist has to decide which stent is suitable for each lesion. On this basis, currently available stents are discussed in regard to their advantages and disadvantages for common application in CHD. New concepts and designs developed to overcome some of the existing problems, like the failure of adaptation to somatic growth, are presented. Thus, in the future, biodegradable or growth stents might replace the currently used generation of stents. This might truly lead to widening indications for the use of stents in the treatment of CHD.

  6. Endoscopic stenting-Where are we now and where can we go?

    Institute of Scientific and Technical Information of China (English)

    Mark Terence McLoughlin; Michael Francis Byrne

    2008-01-01

    Self expanding metal stents (SEMS) play an important role in the management of malignant obstructing lesions in the gastrointestinal tract.Traditionally,they have been used for palliation in malignant gastdc outlet and colonic obstruction and esophageal malignancy.The development of the polyflex stent,which is a removable self expanding plastic stent,allows temporary stent insertion for benign esophageal disease and possibly for patients undergoing neoadjuvant chemotherapy prior to esophagectomy.Potential complications of SEMS insertion include perforation,tumour overgrowth or ingrowth,and stent migration.Newer stents are being developed with the aim of increasing technical and clinical success rates,while reducing complication rates.Other areas of development include biodegradable stents for benign disease and radioactive or drug-eluting stents for malignant disease.It is hoped that,in the future,newer stents will improve our management of these difficult conditions and,possibly,provide prognostic as well as symptomatic benefit in the setting of malignant obstruction.

  7. Advantages of novel BioMimeTM Sirolimus Eluting Coronary Stent system. Moving towards biomimicry.

    Science.gov (United States)

    Upendra, K; Sanjeev, B

    2012-02-01

    Since the first reported use of percutaneous transluminal coronary angioplasty (PTCA), advancements in interventional cardiology arena have been fast paced. Within the last ten years, these developments have been exponential. Developers & clinicians are fast adapting from the learning curve awarded by the time course of DES evolution. In that light BioMimeTM Sirolimus Eluting Coronary Stent comes as a fresh thought in taking stents towards a biomimicry concept. The stent is built on an ultra-low strut thickness (65 µm) cobalt chromium stent platform, using an intelligent hybrid of close and open cells allowing for morphology mediated expansion, employs a well known anti-proliferative - Sirolimus that elutes from a biodegradable co-polymer formulation in 30 days and ensures high coating integrity and low coating thickness of 2 µm. The resultant stent demonstrates almost 100% endothelialization at 30 days in preclinical model and zero percent MACE >18 months in the primary efficacy and safety clinical study.

  8. Combined percutaneous and transurethral lithotripsy for forgotten ureteral stents with giant encrustation.

    Science.gov (United States)

    Rabani, Seyed Mohammadreza

    2012-01-01

    Ureteral stents are widely used in many urologic practices. However, stents can cause significant complications including migration, fragmentation, and encrustation and it may possibly be forgotten. Successful management of a retained, encrusted stent requires combined endourological approaches. To present our experience with the approaches for treating forgotten ureteral stents associated with giant stone formation. Seventy four patients with forgotten ureteral stents were managed by different open (nephrolithotomy and/or cystolithotomy), or endoscopic procedures in our center. Among these, 11 patients had severe encrustation (stones larger than 35 mm within the bladder or kidney) and seven patients of this group, presented at our department between July 2007 and December 2010. Combined endourological procedures percutaneous nephrolithotripsy (PCNL), cystolithotripsy (CLT), transurethral lithotripsy (TUL) were performed in one or 2 separate sessions. In these 7 patients the whole of the stents, especially both ends were encrusted. Initially, cystolithotripsy, retrograde ureteroscopy and TUL were performed in the dorsal lithotomy position. Following this, a gentle attempt was made to retrieve the stent with the help of an ureteroscopic grasper. In some cases the stent was grasped by a hemostat clamp out of the urethral meatus with a gentle traction to facilitate lithotripsy in the ureter and even in the kidney. Finally, a ureteric catheter was placed adjacent to the stent for injection of radio-contrast material to delineate the renal pelvis and the calyces. Then in the same session or later in another session the patient was placed in the prone position and PCNL of the upper coil of the encrusted stent along with calculus was done and the stent was removed. In 5 out of seven patients, the initial indication for stent placement was for urinary stone disease after open nephrolithotomy and pyeloplasty in other centers and in two patients after TUL. All patients

  9. Management of ureteral stenting for postrenal failure during pregnancy after ureteral reimplantation: a case report.

    Science.gov (United States)

    Yoneoka, Yutaka; Kaku, Shoji; Tsuji, Shunichiro; Yamashita, Hiroto; Inoue, Takashi; Kimura, Fuminori; Murakami, Takashi

    2016-04-01

    Vesicoureteral reflux is thought to predispose to urinary tract infection and renal scarring, and ureteral reimplantation in childhood remains the gold standard for its treatment. It has been reported that the risk of postrenal failure during pregnancy is increased among women with Politano-Leadbetter ureteral reimplantation. In previous case reports on patients with progressive hydronephrosis and renal failure during pregnancy after ureteral reimplantation, percutaneous nephrostomy was always required, so there has been no information about the clinical management of such patients by ureteral stenting. Here we report a patient with a history of bilateral ureteral reimplantation, in whom severe hydronephrosis during pregnancy was managed with ureteral stents. A primigravida with severe hydronephrosis was referred to us at 29 weeks of gestation. Bilateral Politano-Leadbetter ureteral reimplantation had been performed at the age of 3 years. She was hospitalized immediately, and bilateral ureteral stents were successfully inserted. Post-obstructive diuresis occurred after the stents were placed. Urinary tract infection developed after removal of the urethral catheter 1 week later, but responded to antibiotic therapy and catheter replacement. Labor was induced at 39 weeks of gestation, with vaginal delivery of a healthy male infant. Both stents were found to have spontaneously migrated into the urethra after delivery. Repeat stenting under spinal anesthesia was required to improve postpartum symptoms of back pain and fever. Right distal ureteral obstruction persisted at 6 months after delivery and repeat ureteral reimplantation is planned. General obstetricians will not necessarily pay attention to a history of Politano-Leadbetter ureteral reimplantation, but these patients should undergo careful monitoring of renal function and urinary tract morphology during perinatal care. In the present case, ureteral stenting was effective for postrenal failure during pregnancy

  10. Biocompatibility of Coronary Stents

    Directory of Open Access Journals (Sweden)

    Thamarasee M. Jeewandara

    2014-01-01

    Full Text Available Cardiovascular disease is the dominant cause of mortality in developed countries, with coronary artery disease (CAD a predominant contributor. The development of stents to treat CAD was a significant innovation, facilitating effective percutaneous coronary revascularization. Coronary stents have evolved from bare metal compositions, to incorporate advances in pharmacological therapy in what are now known as drug eluting stents (DES. Deployment of a stent overcomes some limitations of balloon angioplasty alone, but provides an acute stimulus for thrombus formation and promotes neointimal hyperplasia. First generation DES effectively reduced in-stent restenosis, but profoundly delay healing and are susceptible to late stent thrombosis, leading to significant clinical complications in the long term. This review characterizes the development of coronary stents, detailing the incremental improvements, which aim to attenuate the major clinical complications of thrombosis and restenosis. Despite these enhancements, coronary stents remain fundamentally incompatible with the vasculature, an issue which has largely gone unaddressed. We highlight the latest modifications and research directions that promise to more holistically design coronary implants that are truly biocompatible.

  11. Aetiology of male urethritis in patients recruited from a population with a high HIV prevalence

    NARCIS (Netherlands)

    Sturm, P.D.J.; Moodley, P.; Khan, N.; Ebrahim, S.; Govender, K.; Connolly, C.E.; Sturm, A.W.

    2004-01-01

    The aetiology of urethritis, the significance of potential pathogens and the relation of urethritis to HIV infection were determined in 335 men (cases) with and 100 men (controls) without urethral symptoms. Urethral swab specimens were tested for different organisms by PCR or by culture for Neisseri

  12. Forgotten urological stent.

    Science.gov (United States)

    Bhuiyan, Z H; Bhuiyan, N I; Khan, S A; Tawhid, M H; Islam, M F

    2011-10-01

    "Forgotten" Ureteral stent DJ stent related complication is not uncommon even in the era of modern urology in the developed world. In this context we have undertaken a retro-prospective study in relation to its various causes, complications, management and prevention of forgotten stents in a single teaching institute. The study period was from January'04 to December'09. The sample size was 60. The effect of "forgotten stent" in our study reflects mild UTI to various complications including severe renal failure. We had approached all of our cases judiciously using various modalities of minimal access endourological techniques either alone or in combinations with successful outcome. The study concluded that it is vary easy to prevent "forgotten stent" and so its complications. However if we confront such unwanted complications that could be managed successfully with the use of endourological techniques. We did not use other techniques like laparoscopy and open surgery in this study.

  13. Everolimus-eluting coronary stents

    Directory of Open Access Journals (Sweden)

    Alejandro Saez

    2010-09-01

    Full Text Available Alejandro Saez, Raul MorenoDivision of Interventional Cardiology, University Hospital La Paz, Madrid, SpainAbstract: Bare metal stents enabled a reduction in the risk of early procedural complications and restenosis in comparison with balloon angioplasty alone, but introduced a new and device-specific iatrogenic condition, ie, in-stent restenosis due to increased neointimal hyperplasia. Sirolimus- and paclitaxel-eluting stents reduce restenosis and the need for new revascularizations in comparison with bare metal stents, although at the cost of a slight increase in the risk of late stent thrombosis and a need for prolonged dual antiplatelet therapy. Everolimus is an analog of sirolimus with an increased solubility. In this review, the currently available evidence for everolimus-eluting stents is revised, including randomized trials against bare metal stents, and head-to-head trials comparing this stent with other drug-eluting stents.Keywords: coronary stents, restenosis, everolimus, review

  14. Drug-eluting bioabsorbable magnesium stent.

    Science.gov (United States)

    Di Mario, Carlo; Griffiths, Huw; Goktekin, Omer; Peeters, Nicolas; Verbist, Jan; Bosiers, Marc; Deloose, Koen; Heublein, Bernhard; Rohde, Roland; Kasese, Victor; Ilsley, Charles; Erbel, Raimund

    2004-12-01

    Current stent technology is based on the use of permanent implants that remain life long in the vessel wall, far beyond the time required for the prosthesis to accomplish its main goals of sealing dissection and preventing wall recoil. With the possibility to implant long vessel segments using antiproliferative drugs to prevent restenosis, the practice of transforming the coronary vessels into stiff tubes with a full metal jacket covering all side branches and being unable to adjust to the long-term wall changes, including wall remodeling with lumen ectasia becomes a serious concern. In this article, we describe the first biodegradable stent based on a magnesium alloy that allows controlled corrosion with release to the vessel wall and the blood stream of a natural body component such as magnesium with beneficial antithrombotic, antiarrhythmic, and antiproliferative properties. We also discuss the animal experiments and the initial clinical applications in 20 patients with implants below the knee, with final results soon to be released, and the plans for the first coronary study. The results of these last two studies will indicate whether the absence of a permanent implant and the antiproliferative properties shown in animals are sufficient to prevent the restenotic process in humans or whether the prosthesis must be modified by adding the biodegradable coating with conventional antiproliferative drugs.

  15. Endothelial Cellular Responses to Biodegradable Metal Zinc.

    Science.gov (United States)

    Ma, Jun; Zhao, Nan; Zhu, Donghui

    Biodegradable zinc (Zn) metals, a new generation of biomaterials, have attracted much attention due to their excellent biodegradability, bioabsorbability, and adaptability to tissue regeneration. Compared with magnesium (Mg) and iron (Fe), Zn exhibits better corrosion and mechanical behaviors in orthopedic and stent applications. After implantation, Zn containing material will slowly degrade, and Zn ions (Zn(2+)) will be released to the surrounding tissue. For stent applications, the local Zn(2+)concentration near endothelial tissue/cells could be high. However, it is unclear how endothelia will respond to such high concentrations of Zn(2+), which is pivotal to vascular remodeling and regeneration. Here, we evaluated the short-term cellular behaviors of primary human coronary artery endothelial cells (HCECs) exposed to a concentration gradient (0-140 μM) of extracellular Zn(2+). Zn(2+) had an interesting biphasic effect on cell viability, proliferation, spreading, and migration. Generally, low concentrations of Zn(2+) promoted viability, proliferation, adhesion, and migration, while high concentrations of Zn(2+) had opposite effects. For gene expression profiles, the most affected functional genes were related to cell adhesion, cell injury, cell growth, angiogenesis, inflammation, vessel tone, and coagulation. These results provide helpful information and guidance for Zn-based alloy design as well as the controlled release of Zn(2+)in stent and other related medical applications.

  16. Endovascular Gene Delivery from a Stent Platform: Gene- Eluting Stents.

    Science.gov (United States)

    Fishbein, Ilia; Chorny, Michael; Adamo, Richard F; Forbes, Scott P; Corrales, Ricardo A; Alferiev, Ivan S; Levy, Robert J

    A synergistic impact of research in the fields of post-angioplasty restenosis, drug-eluting stents and vascular gene therapy over the past 15 years has shaped the concept of gene-eluting stents. Gene-eluting stents hold promise of overcoming some biological and technical problems inherent to drug-eluting stent technology. As the field of gene-eluting stents matures it becomes evident that all three main design modules of a gene-eluting stent: a therapeutic transgene, a vector and a delivery system are equally important for accomplishing sustained inhibition of neointimal formation in arteries treated with gene delivery stents. This review summarizes prior work on stent-based gene delivery and discusses the main optimization strategies required to move the field of gene-eluting stents to clinical translation.

  17. Anaerobic biodegradability of macropollutants

    DEFF Research Database (Denmark)

    Angelidaki, Irini

    2002-01-01

    A variety of test procedures for determination of anaerobic biodegradability has been reported. This paper reviews the methods developed for determination of anaerobic biodegradability of macro-pollutants. Anaerobic biodegradability of micro-pollutants is not included. Furthermore, factors...

  18. Biodegradation and bioremediation

    DEFF Research Database (Denmark)

    Albrechtsen, H.-J.

    1996-01-01

    Anmeldelse af Alexander,M.: Biodegradation and bioremediation. Academic Press, Sandiego, USA, 1994......Anmeldelse af Alexander,M.: Biodegradation and bioremediation. Academic Press, Sandiego, USA, 1994...

  19. One‑stage Anastomotic Urethroplasty for Traumatic Urethral ...

    African Journals Online (AJOL)

    occur in association with posterior urethral injuries in 10–20% of cases.[3,6,7] ... Department of Surgery, Urology Unit, Federal Teaching Hospital, Abakaliki, Ebonyi State, 1Department of Radiation. Medicine ..... urethro-cutaneous fistulae.

  20. Urethral catheterization:The need for adequate undergraduate ...

    African Journals Online (AJOL)

    E.V. Ezenwa

    2016-12-26

    Dec 26, 2016 ... There were 60 respondents who all graduated from medical schools in Nigeria except 2 .... effects of urethral catheterization (UC) taught by simulated training ... Outcomes and standards for under- graduate medical education.

  1. A novel cannulation technique for difficult urethral catheterization

    Directory of Open Access Journals (Sweden)

    Mehmet Kaynar

    2016-03-01

    Full Text Available Introduction: To propose a novel cannulation technique for difficult urethral catheterization procedures. Technique: The sheath tip of an intravenous catheter is cut off, replaced to the needle tip and pushed through the distal drainage side hole to Foley catheter tip, and finally withdrawn for cannulation. In situations making urethral catheterization difficult, a guide wire is placed under direct vision. The modified Foley catheter is slid successfully over the guide wire from its distal end throughout the urethral passage into the bladder. Results: The modified Foley catheter was used successfully in our clinic in cases requiring difficult urethral catheterization. Conclusions: This easy and rapid modification of a Foley catheter may minimize the potential complications of blind catheter placement in standard catheterization.

  2. current concepts in the management of anterior urethral strictures

    African Journals Online (AJOL)

    iam

    urethral substitutes have been compared to other techniques of urethroplasty as seen over the. last decade. .... tube for 6 to 8 weeks to determine the tendency for such hydro dilated .... the urethra and penile curvature at erection 51. These.

  3. Similarities and differences in coatings for magnesium-based stents and orthopaedic implants

    Directory of Open Access Journals (Sweden)

    Jun Ma

    2014-07-01

    Full Text Available Magnesium (Mg-based biodegradable materials are promising candidates for the new generation of implantable medical devices, particularly cardiovascular stents and orthopaedic implants. Mg-based cardiovascular stents represent the most innovative stent technology to date. However, these products still do not fully meet clinical requirements with regards to fast degradation rates, late restenosis, and thrombosis. Thus various surface coatings have been introduced to protect Mg-based stents from rapid corrosion and to improve biocompatibility. Similarly, different coatings have been used for orthopaedic implants, e.g., plates and pins for bone fracture fixation or as an interference screw for tendon-bone or ligament-bone insertion, to improve biocompatibility and corrosion resistance. Metal coatings, nanoporous inorganic coatings and permanent polymers have been proved to enhance corrosion resistance; however, inflammation and foreign body reactions have also been reported. By contrast, biodegradable polymers are more biocompatible in general and are favoured over permanent materials. Drugs are also loaded with biodegradable polymers to improve their performance. The key similarities and differences in coatings for Mg-based stents and orthopaedic implants are summarized.

  4. Expandable bioresorbable endovascular stent. I. Fabrication and properties.

    Science.gov (United States)

    Su, Shih-Horng; Chao, Robert Y N; Landau, Charles L; Nelson, Kevin D; Timmons, Richard B; Meidell, Robert S; Eberhart, Robert C

    2003-06-01

    A bioresorbable, expandable poly(L-lactic acid) stent has been designed, based on a linear, continuous coil array principle, by which multiple furled lobes convert to a single lobe upon balloon expansion, without heating. Stent strength and compliance are sufficient to permit deployment by a conventional balloon angioplasty catheter. Several multiple lobe configurations were investigated, with expansion ratios ranging from 1.4 to 1.9 and expanded diameters ranging from 2.3 to 4.7 mm. Compression resistance of the expanded stent is dependent on fiber coil density and fiber ply. A range sufficient for endovascular service was obtained, with less than 4% elastic recoil in six day saline incubation studies. Surface plasma treatment with di(ethylene glycol) vinyl ether significantly reduced platelet adhesion in a 1 h porcine arteriovenous shunt model. Patency was maintained in one week implant studies in the porcine common femoral artery. However, a strong inflammatory response, and significant reduction of the vascular lumen were observed following two weeks implantation. The design principles and fabrication techniques for this bioresorbable stent are sufficiently versatile that a broad range of applications can be addressed. Much work remains to be done, including long-term evaluation of the inflammatory response, and of polymer degradation. The results of this study demonstrate the feasibility of expandable biodegradable stent design and deployment by conventional means.

  5. Intravascular ultrasound assessed incomplete stent apposition and stent fracture in stent thrombosis after bare metal versus drug-eluting stent treatment the Nordic Intravascular Ultrasound Study (NIVUS)

    DEFF Research Database (Denmark)

    Kosonen, Petteri; Vikman, Saila; Jensen, Lisette Okkels;

    2013-01-01

    This prospective multicenter registry used intravascular ultrasound (IVUS) in patients with definite stent thrombosis (ST) to compare rates of incomplete stent apposition (ISA), stent fracture and stent expansion in patients treated with drug-eluting (DES) versus bare metal (BMS) stents. ST...... is a rare, but potential life threatening event after coronary stent implantation. The etiology seems to be multifactorial....

  6. Endoscopic Dilatation versus Oesophageal Stent in Benign Oesophageal Stricture

    Directory of Open Access Journals (Sweden)

    Hadyanto Caputra

    2016-09-01

    Full Text Available Aim: Oesophageal stricture is one of the causes of dysphagia. It is a condition in which the lumen of oesophagus is narrowed by fibrotic tissue in the oesophageal wall. It is usually caused by inflammation or any other cause that leads to necrotizing of tissue. It is mainly differentiated into benign or malignant. The aim of this article is to answer the clinical question on the effectiveness of oesophageal stenting compared to endoscopic dilatation in patient with benign oesophageal stricture due to ingestion of corrosive substances, who had undergone several endoscopic dilatations. Method: We conducted search of relevant articles using PubMed search engine to answer the clinical question. Keywords being used during the search process were: ("oesophageal stricture"[All Fields] OR "oesophageal stenosis"[All Fields] AND (("dilatation"[All Fields] AND ("stents"[MeSH Terms] OR "stents"[All Fields] OR "stent"[All Fields]. Results were further converged by adding specific filters, which were full text articles and clinical trial. Results: The chosen article was further appraised in order to identify its validity and eligibility to answer the clinical question. We chose to use CONSORT (statement to improve the quality of reporting of RCTs to facilitate the critical appraisal and interpretation of RCTs. Conclusion: Stenting was associated with greater dysphagia, co-medication and adverse events. No randomized controlled trials which compared biodegradable stents with other stents or with balloon dilatation was identified. Lack of adequately robust evidence for effectiveness and cost-effectiveness formed the rationale of this trial.

  7. Urethral obstruction from dislodged bladder Diverticulum stones: a case report

    Directory of Open Access Journals (Sweden)

    Okeke Linus I

    2012-11-01

    Full Text Available Abstract Background Secondary urethral stone although rare, commonly arises from the kidneys, bladder or are seen in patients with urethral stricture. These stones are either found in the posterior or anterior urethra and do result in acute urinary retention. We report urethral obstruction from dislodged bladder diverticulum stones. This to our knowledge is the first report from Nigeria and in English literature. Case presentation A 69 year old, male, Nigerian with clinical and radiological features of acute urinary retention, benign prostate enlargement and bladder diverticulum. He had a transurethral resection of the prostate (TURP and was lost to follow up. He re-presented with retained urethral catheter of 4months duration. The catheter was removed but attempt at re-passing the catheter failed and a suprapubic cystostomy was performed. Clinical examination and plain radiograph of the penis confirmed anterior and posterior urethral stones. He had meatotomy and antegrade manual stone extraction with no urethra injury. Conclusions Urethral obstruction can result from inadequate treatment of patient with benign prostate enlargement and bladder diverticulum stones. Surgeons in resource limited environment should be conversant with transurethral resection of the prostate and cystolithotripsy or open prostatectomy and diverticulectomy.

  8. Renal Artery Stent Outcomes

    Science.gov (United States)

    Murphy, Timothy P.; Cooper, Christopher J.; Matsumoto, Alan H.; Cutlip, Donald E.; Pencina, Karol M.; Jamerson, Kenneth; Tuttle, Katherine R.; Shapiro, Joseph I.; D’Agostino, Ralph; Massaro, Joseph; Henrich, William; Dworkin, Lance D.

    2016-01-01

    BACKGROUND Multiple randomized clinical trials comparing renal artery stent placement plus medical therapy with medical therapy alone have not shown any benefit of stent placement. However, debate continues whether patients with extreme pressure gradients, stenosis severity, or baseline blood pressure benefit from stent revascularization. OBJECTIVES The study sought to test the hypothesis that pressure gradients, stenosis severity, and/or baseline blood pressure affects outcomes after renal artery stent placement. METHODS Using data from 947 patients with a history of hypertension or chronic kidney disease from the largest randomized trial of renal artery stent placement, the CORAL (Cardiovascular Outcomes in Renal Atherosclerotic Lesions) study, we performed exploratory analyses to determine if subsets of patients experienced better outcomes after stent placement than the overall cohort. We examined baseline stenosis severity, systolic blood pressure, and translesion pressure gradient (peak systolic and mean) and performed interaction tests and Cox proportional hazards analyses for the occurrence of the primary endpoint through all follow-up, to examine the effect of these variables on outcomes by treatment group. RESULTS There were no statistically significant differences in outcomes based on the examined variables nor were there any consistent nonsignificant trends. CONCLUSIONS Based on data from the CORAL randomized trial, there is no evidence of a significant treatment effect of the renal artery stent procedure compared with medical therapy alone based on stenosis severity, level of systolic blood pressure elevation, or according to the magnitude of the transstenotic pressure gradient. (Benefits of Medical Therapy Plus Stenting for Renal Atherosclerotic Lesions [CORAL]; NCT00081731) PMID:26653621

  9. In-vitro release of anti-proliferative paclitaxel from novel balloon-expandable polycaprolactone stents

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shih-Jung, E-mail: shihjung@mail.cgu.edu.tw [Department of Mechanical Engineering, Chang Gung University, Taiwan (China); Hsiao, Chao-Ying [Department of Mechanical Engineering, Chang Gung University, Taiwan (China); Chen, Jan-Kan [Department of Physiology and Pharmacology, Chang Gung University, Taiwan (China); Liu, Kuo-Sheng [Department of Mechanical Engineering, Chang Gung University, Taiwan (China); Department of Cardiovascular Surgery, Chang Gung Memorial Hospital, Taiwan (China); Lee, Cheng-Hung [Department of Mechanical Engineering, Chang Gung University, Taiwan (China); Second Section of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Taiwan (China)

    2011-07-20

    This report investigated the in-vitro release characteristics of paclitaxel from novel balloon-expandable polycaprolactone stents. Polycaprolactone stents were first manufactured by a lab-made micro-injection molding machine. Paclitaxel and polylactide-polyglycolide (PLGA) copolymer were dissolved in acetonitrile and were coated onto the surface of the stents by a spray coating device, which was designed and built especially for this study. An elution method was utilized to characterize the in-vitro release characteristics of paclitaxel. The high performance liquid chromatography (HPLC) analysis showed that biodegradable stents could provide sustained release of paclitaxel for more than 70 days. Various process parameters that controlled the release rate of paclitaxel were studied. The experimental results suggested that the total period of drug release could be prolonged by adopting 75:25 PLGA copolymers, employing multi-layer coatings, and increasing the drug loading. In addition, the effectiveness of eluted paclitaxel on cell behavior was examined. The results showed that the eluted drug could effectively inhibit the proliferation of smooth muscle cells. - Research Highlights: {yields} We investigate the in-vitro release characteristics of paclitaxel from polycaprolactone stents. {yields} Biodegradable stents provide sustained release of paclitaxel for more than 70 days. {yields} The eluted drug effectively inhibits the proliferation of smooth muscle cells.

  10. Stent Fracture after Everolimus-Eluting Stent Implantation

    Directory of Open Access Journals (Sweden)

    Ali S. Almasood

    2011-01-01

    Full Text Available Compared with bare-metal stents, drug-eluting stents (DES have greatly reduced the risk of in-stent restenosis (ISR by inhibiting neointimal growth. Nevertheless, DES are still prone to device failure, which may lead to cardiac events. Recently, stent fracture (SF has emerged as a potential mechanism of DES failure that is associated with ISR. Stent fracture is strongly related to stent type, and prior reports suggest that deployment of sirolimus eluting stents (SES may be associated with a higher risk of SF compared to other DES. Everolimus eluting stents (EESs represent a new generation of DES with promising results. The occurrence of SF with EES has not been well established. The present paper describes two cases of EES fracture associated with ISR.

  11. Nanomaterial coatings applied on stent surfaces.

    Science.gov (United States)

    Bagheri, Mahsa; Mohammadi, Marzieh; Steele, Terry Wj; Ramezani, Mohammad

    2016-05-01

    The advent of percutaneous coronary intervention and intravascular stents has revolutionized the field of interventional cardiology. Nonetheless, in-stent restenosis, inflammation and late-stent thrombosis are the major obstacles with currently available stents. In order to enhance the hemocompatibility of stents, advances in the field of nanotechnology allow novel designs of nanoparticles and biomaterials toward localized drug/gene carriers or stent scaffolds. The current review focuses on promising polymers used in the fabrication of newer generations of stents with a short synopsis on atherosclerosis and current commercialized stents, nanotechnology's impact on stent development and recent advancements in stent biomaterials is discussed in context.

  12. Cobalt chromium stents versus stainless steel stents in diabetic patients

    Directory of Open Access Journals (Sweden)

    Mahmoud Ahmed Tantawy

    2014-03-01

    Conclusions: We concluded that no significant statistical difference was found between the two stents (cobalt-chromium alloy bare metal stent versus conventional bare metal stainless steel stent in diabetic patients regarding (initial procedural success, in-hospital complications, the incidence of ISR at follow up, event-free survival at follow up.

  13. Future developments in biliary stenting

    Directory of Open Access Journals (Sweden)

    Hair CD

    2013-06-01

    Full Text Available Clark D Hair,1 Divyesh V Sejpal21Department of Medicine, Section of Gastroenterology and Hepatology, Baylor College of Medicine, Houston, TX, USA; 2Department of Medicine, Section of Gastroenterology, Hofstra North Shore-LIJ School of Medicine, North Shore University Hospital, Manhasset, NY, USAAbstract: Biliary stenting has evolved dramatically over the past 30 years. Advancements in stent design have led to prolonged patency and improved efficacy. However, biliary stenting is still affected by occlusion, migration, anatomical difficulties, and the need for repeat procedures. Multiple novel plastic biliary stent designs have recently been introduced with the primary goals of reduced migration and improved ease of placement. Self-expandable bioabsorbable stents are currently being investigated in animal models. Although not US Food and Drug Administration approved for benign disease, fully covered self-expandable metal stents are increasingly being used in a variety of benign biliary conditions. In malignant disease, developments are being made to improve ease of placement and stent patency for both hilar and distal biliary strictures. The purpose of this review is to describe recent developments and future directions of biliary stenting.Keywords: plastic stents, self-expandable metal stents, drug eluting stents, bioabsorbable stents, malignant biliary strictures, benign biliary strictures

  14. Biodegradable Shape Memory Polymers in Medicine.

    Science.gov (United States)

    Peterson, Gregory I; Dobrynin, Andrey V; Becker, Matthew L

    2017-09-21

    Shape memory materials have emerged as an important class of materials in medicine due to their ability to change shape in response to a specific stimulus, enabling the simplification of medical procedures, use of minimally invasive techniques, and access to new treatment modalities. Shape memory polymers, in particular, are well suited for such applications given their excellent shape memory performance, tunable materials properties, minimal toxicity, and potential for biodegradation and resorption. This review provides an overview of biodegradable shape memory polymers that have been used in medical applications. The majority of biodegradable shape memory polymers are based on thermally responsive polyesters or polymers that contain hydrolyzable ester linkages. These materials have been targeted for use in applications pertaining to embolization, drug delivery, stents, tissue engineering, and wound closure. The development of biodegradable shape memory polymers with unique properties or responsiveness to novel stimuli has the potential to facilitate the optimization and development of new medical applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Magnetic Nanoparticle-Mediated Targeting of Cell Therapy Reduces In-Stent Stenosis in Injured Arteries.

    Science.gov (United States)

    Polyak, Boris; Medved, Mikhail; Lazareva, Nina; Steele, Lindsay; Patel, Tirth; Rai, Ahmad; Rotenberg, Menahem Y; Wasko, Kimberly; Kohut, Andrew R; Sensenig, Richard; Friedman, Gary

    2016-09-19

    Although drug-eluting stents have dramatically reduced the recurrence of restenosis after vascular interventions, the nonselective antiproliferative drugs released from these devices significantly delay reendothelialization and vascular healing, increasing the risk of short- and long-term stent failure. Efficient repopulation of endothelial cells in the vessel wall following injury may limit complications, such as thrombosis, neoatherosclerosis, and restenosis, through reconstitution of a luminal barrier and cellular secretion of paracrine factors. We assessed the potential of magnetically mediated delivery of endothelial cells (ECs) to inhibit in-stent stenosis induced by mechanical injury in a rat carotid artery stent angioplasty model. ECs loaded with biodegradable superparamagnetic nanoparticles (MNPs) were administered at the distal end of the stented artery and localized to the stent using a brief exposure to a uniform magnetic field. After two months, magnetic localization of ECs demonstrated significant protection from stenosis at the distal part of the stent in the cell therapy group compared to both the proximal part of stent in the cell therapy group and the control (stented, nontreated) group: 1.7-fold (p < 0.001) less reduction in lumen diameter as measured by B-mode and color Doppler ultrasound, 2.3-fold (p < 0.001) less reduction in the ratios of peak systolic velocities as measured by pulsed wave Doppler ultrasound, and 2.1-fold (p < 0.001) attenuation of stenosis as determined through end point morphometric analysis. The study thus demonstrates that magnetically assisted delivery of ECs is a promising strategy for prevention of vessel lumen narrowing after stent angioplasty procedure.

  16. Measurement of urethral closure function in women with stress urinary incontinence

    DEFF Research Database (Denmark)

    Klarskov, N; Scholfield, D; Soma, K;

    2009-01-01

    , double-blind, placebo controlled, crossover study 17 women with stress urinary incontinence or mixed urinary incontinence received 4 mg esreboxetine or placebo for 7 to 9 days followed by a washout period before crossing over treatments. Urethral pressure reflectometry and urethral pressure profilometry...... esreboxetine patients had significantly fewer incontinence episodes and reported a treatment benefit (global impression of change) compared to placebo. CONCLUSIONS: The opening pressure measured with urethral pressure reflectometry was less variable compared to the parameters measured with urethral pressure...

  17. Acute urinary retention in women due to urethral calculi: A rare case

    OpenAIRE

    2014-01-01

    We present a case of a 51-year-old woman with acute urinary retention caused by a urethral calculus. Urethral calculi in women are extremely rare and are usually formed in association with underlying genitourinary pathology. In this case, however, no pathology was detected via thorough urological evaluation. We discuss the pathogenesis, clinical presentation and treatment of urethral calculi. To our knowledge, this is the second reported case of a primary urethral calculus in a female with an...

  18. The urethral glands of male mice in relation to depletion of secretory granules upon mating.

    Science.gov (United States)

    Parr, M B; de França, L R; Kepple, L; Ying, L; Parr, E L; Russell, L D

    1994-08-01

    The present study describes the effects of mating on urethral gland acinar cells in male mice. Histological and morphometric analysis demonstrated that there was a depletion of secretory granules in the urethral glands during mating. However, no change occurred in the rough endoplasmic reticulum containing tubular elements. The results indicate that the urethral glands are functional during mating. The timing of their granule depletion suggests that urethral gland secretions may contribute to the formation of semen or the copulation plug.

  19. Biodegradable thermogels.

    Science.gov (United States)

    Park, Min Hee; Joo, Min Kyung; Choi, Bo Gyu; Jeong, Byeongmoon

    2012-03-20

    All living creatures respond to external stimuli. Similarly, some polymers undergo conformational changes in response to changes in temperature, pH, magnetic field, electrical field, or the wavelength of light. In one type of stimuli-responsive polymer, thermogel polymers, the polymer aqueous solution undergoes sol-to-gel transition as the temperature increases. Drugs or cells can be mixed into the polymer aqueous solution when it is in its lower viscosity solution state. After injection of the solution into a target site, heating prompts the formation of a hydrogel depot in situ, which can then act as a drug releasing system or a cell growing matrix. In this Account, we describe key materials developed in our laboratory for the construction of biodegradable thermogels. We particularly emphasize recently developed polypeptide-based materials where the secondary structure and nanoassembly play an important role in the determining the material properties. This Account will provide insights for controlling parameters, such as the sol-gel transition temperature, gel modulus, critical gel concentration, and degradability of the polymer, when designing a new thermogel system for a specific biomedical application. By varying the stereochemistry of amino acids in polypeptides, the molecular weight of hydrophobic/hydrophilic blocks, the composition of the polypeptides, the hydrophobic end-capping of the polypeptides, and the microsequences of a block copolymer, we have controlled the thermosensitivity and nanoassembly patterns of the polymers. We have investigated a series of thermogel biodegradable polymers. Polymers such as poly(lactic acid-co-glycolic acid), polycaprolactone, poly(trimethylene carbonate), polycyanoacrylate, sebacic ester, polypeptide were used as hydrophobic blocks, and poly(ethylene glycol) and poly(vinyl pyrrolidone) were used as hydrophilic blocks. To prepare a polymer sensitive to pH and temperature, carboxylic acid or amine groups were introduced

  20. Effect of fesoterodine on urethral closure function in women with stress urinary incontinence assessed by urethral pressure reflectometry

    DEFF Research Database (Denmark)

    Klarskov, Niels; Darekar, Amanda; Scholfield, David

    2014-01-01

    INTRODUCTION AND HYPOTHESIS: The aim was to evaluate, using urethral pressure reflectometry (UPR), the effect of fesoterodine on urethral function in women with stress urinary incontinence (SUI). METHODS: Women aged 18 to 65 years were eligible for this randomised, double-blind, placebo-controlle......INTRODUCTION AND HYPOTHESIS: The aim was to evaluate, using urethral pressure reflectometry (UPR), the effect of fesoterodine on urethral function in women with stress urinary incontinence (SUI). METHODS: Women aged 18 to 65 years were eligible for this randomised, double-blind, placebo......-controlled, crossover study if they had had clinically significant SUI or SUI-predominant mixed urinary incontinence for >3 months. Each participant received fesoterodine 4 mg, fesoterodine 8 mg, and placebo once daily for 7 days, with a 7- to 10-day washout between treatments. UPR was performed at baseline and 4 to 8...... significant differences were seen between fesoterodine 4 mg or fesoterodine 8 mg and placebo in opening urethral pressure (primary endpoint) or other UPR endpoints. No statistically significant differences were seen between either fesoterodine dose and placebo in the change from baseline in the bladder diary...

  1. [Laser hair removal for urethral hair after hypospadias repair].

    Science.gov (United States)

    Kaneko, Tomoyuki; Nishimatsu, Hiroaki; Ogushi, Tetsuo; Sugimoto, Masayuki; Asakage, Yasuyuki; Kitamura, Tadaichi

    2008-01-01

    A 56-year-old male was admitted for induration of ventral side of the penile shaft. Computed tomography showed a large urethral calculus in the distal urethra. About 50 years previously, he had undergone multi-staged urethroplasty for hypospadias. He had also suffered from recurrent urethral calculi managed by urethrolithotomy 5 and 2 years before the admission. Urethrolithotomy revealed hair-bearing urethral calculus. Instillation of depilating agent containing thioglycolate into the neourethra for preventing hair regrowth was ineffective. Transurethral laser hair removal of neourethra was subsequently performed. All the neourethral follicles were ablated with GaAlAs diode laser (wave length 810 nm; at a power of 15W for 2 seconds) through a side-firing laser fiber. Another three operations were performed for a few regrown hairs at a power of 20-30W. Convalescence was uneventful. The patient is free of hair regrowth except for a hair at five months of follow-up.

  2. A RARE CONDITION OF MULTIPLE URETHRAL STONES WITH MEATAL STENOSIS

    Directory of Open Access Journals (Sweden)

    Navkiran Kaur

    2016-07-01

    Full Text Available Multiple urethral stones are a rare occurrence commonly resulting from migration of renal stones and rarely arising de novo secondary to the other pathology such as urethral diverticulum, strictures, neurogenic bladder, meatal stenosis, and obstructing tumours such as adenomatous metaplasia of the uroepithelium and hypospadias. We report the case of a 47-year-old male presenting with difficulty in micturition resulting from impaction of multiple stones within the urethra. On retrograde urethrogram, meatal stenosis was also seen along with multiple urethral stones. On ultrasonography of patient, renal stones were also found. Patient was managed surgically and stones were extracted. This paper summarises the topic and discusses the radiological and its clinical implication of this unusual condition.

  3. Balanitis xerotica obliterans with urethral stricture after hypospadias repair.

    Science.gov (United States)

    Uemura, S; Hutson, J M; Woodward, A A; Kelly, J H; Chow, C W

    2000-01-01

    Three cases of urethral stricture due to balanitis xerotica obliterans (BXO) after hypospadias repair are reported. The first patient showed white, dense scarring on the prepuce before the hypospadias repair and developed a stricture of the urethra after the operation. The second and the third were uneventful for 6 and 2 years, respectively, after the hypospadias repair, and then developed urethral strictures. Pathologic diagnosis of the stenotic lesion is essential. Complete excision of the affected urethra with topical steroid ointment or sublesional triamcinolone injection is recommended for this condition. Although the complication of BXO after hypospadias repair is rare (3 out of 796 cases with hypospadias in our series), surgeons need to be aware of this condition as a cause for late onset of urethral problems.

  4. Urethral triplication with meatuses terminating on the penis: a rare case presenting with bifid urinary stream

    Energy Technology Data Exchange (ETDEWEB)

    Hirselj, Daniel A.; Jayanthi, Venkata R. [Nationwide Children' s Hospital, Department of Pediatric Urology, Columbus, OH (United States); Lowe, Gregory K. [The Ohio State University Medical Center, Department of Urology, Columbus, OH (United States)

    2009-11-15

    Urethral duplication is an uncommon clinical finding, and classification systems have been described to explain the clinical findings. Urethral triplication is an extremely uncommon diagnosis, with few published case reports. We present the rare case of an infant noted to have a bifid urinary stream and found to have urethral triplication on voiding cystourethrography. (orig.)

  5. Neisseria meningitidis ST11 Complex Isolates Associated with Nongonococcal Urethritis, Indiana, USA, 2015–2016

    Science.gov (United States)

    Toh, Evelyn; Gangaiah, Dharanesh; Batteiger, Byron E.; Williams, James A.; Arno, Janet N.; Tai, Albert; Batteiger, Teresa A.

    2017-01-01

    At a clinic in Indianapolis, Indiana, USA, we observed an increase in Neisseria gonorrhoeae–negative men with suspected gonococcal urethritis who had urethral cultures positive for N. meningitidis. We describe genomes of 2 of these N. meningitidis sequence type 11 complex urethritis isolates. Clinical evidence suggests these isolates may represent an emerging urethrotropic clade. PMID:28098538

  6. Drug-eluting stents: current issues

    NARCIS (Netherlands)

    P.W.J.C. Serruys (Patrick); A.T.L. Ong (Andrew)

    2005-01-01

    textabstractEarly stent thrombosis occurs in about 1% to 1.5% of patients with drug-eluting stents, very similar to the rate with bare-metal stents. Late stent thrombosis is more of a concern with drug-eluting stents, with an incidence of at least 0.35%. I would urge caution if you feel you have to

  7. Drug-eluting stents: current issues

    NARCIS (Netherlands)

    P.W.J.C. Serruys (Patrick); A.T.L. Ong (Andrew)

    2005-01-01

    textabstractEarly stent thrombosis occurs in about 1% to 1.5% of patients with drug-eluting stents, very similar to the rate with bare-metal stents. Late stent thrombosis is more of a concern with drug-eluting stents, with an incidence of at least 0.35%. I would urge caution if you feel you have to

  8. [Physical properties of Strecker stents].

    Science.gov (United States)

    Okuda, Y; Sawada, S; Morioka, N; Kodani, K; Ihaya, T; Tanigawa, N; Kobayashi, M; Hashimoto, M; Oouchi, Y; Shimatani, Y

    1995-02-01

    Strecker stent is a balloon-expandable metallic stent that is made of knitted tantalum wire mesh in order to Maintain flexibility. Therefore, the prosthesis is well suited to irregular and tortuous tube organs. We performed several physical experiments using 8 mm and 6 mm diameter stents made of 0.1 mm diameter wire filament. The bearing power of the 8 mm diameter stent against the circumferential compression pressure was divided into two groups, that is, 77-100% and under 66% of expansile rate. The capacity bearing the circumferential compression pressure of the latter group was greater than that of the former. Further, the bearing power of the 6 mm diameter stent was greater than that of the 56% expansile rate of the 8 mm diameter stent. The smaller the expansile rate of the stent, the smaller the minimum radius of curvature within the limits of the stent's plastic. To evaluate the suitability of the stent in clinical use, we made two projections on the inner surface of rubber tubes, and the stents were placed into the rubber tubes at different expansile rates. We evaluated the degree of contact of the stents against the rubber wall by taking soft X-ray photographs. The stents showed good suitability under the condition of incomplete expansion. For the above reasons, we concluded that, from the view-point of bearing power, the stent should be placed in the full expansile state. From the viewpoint of contact against the vessel wall, the stent should be placed in the incomplete expansile state.

  9. Anterior urethral valves: not such a benign condition…

    Directory of Open Access Journals (Sweden)

    Omar eCruz-Diaz

    2013-11-01

    Full Text Available Purpose: Anterior urethral valves (AUV is an unusual cause of congenital obstruction of the male urethra, being 15 to 30 times less common than posterior urethral valves (PUV. It has been suggested that patients with congenital anterior urethral obstruction have a better prognosis than those with PUV.The long term prognosis of anterior urethral valves is not clear in the literature. In this report we describe our experience and long-term follow up of patients with AUV.Materials and methods: We retrospectively identified 13 patients who presented with the diagnosis of AUV in our institutions between 1994 and 2012. From the 11 patients included, we evaluated the gestational age, ultrasound and voiding cystourethrogram findings, age upon valve ablation, micturition pattern, creatinine and clinical follow up.Results: Between 1994 and 2012 we evaluated 150 patients with the diagnosis of urethral valves, where 11 patients (7.3% had AUV and an adequate follow up. Mean follow up is 6.3 years. 5 patients (45.4% had pre-natal diagnosis of AUV. The most common prenatal ultrasonographic finding was bilateral hydronephrosis and distended bladder.The mean gestational age was 37.6 weeks. Postnatally, 90% had trabeculated bladder, 80% hydronephrosis and 40% renal dysplasia. The most common clinical presentation was urinary tract infection in 5 patients (45.4%.7 patients (63.6% had primary transurethral valve resection or laser ablation and 3 patients (27.2% had primary vesicostomies. One boy (9.1% had urethrostomy with urethral diverticulum excision. 2 patients (18.2% developed end-stage renal disease (ESRD.Conclusions: Early urinary tract obstruction resulted in ESRD in 18% of our patient population. In our series, the complication rate and the evolution to renal failure are high and similar to patients with PUV. In patients with AUV we recommend long-term follow up and close evaluation of patient’s bladder and renal function.

  10. A phenomenological constitutive model for the nonlinear viscoelastic responses of biodegradable polymers

    KAUST Repository

    Khan, Kamran

    2012-11-09

    We formulate a constitutive framework for biodegradable polymers that accounts for nonlinear viscous behavior under regimes with large deformation. The generalized Maxwell model is used to represent the degraded viscoelastic response of a polymer. The large-deformation, time-dependent behavior of viscoelastic solids is described using an Ogden-type hyperviscoelastic model. A deformation-induced degradation mechanism is assumed in which a scalar field depicts the local state of the degradation, which is responsible for the changes in the material\\'s properties. The degradation process introduces another timescale (the intrinsic material clock) and an entropy production mechanism. Examples of the degradation of a polymer under various loading conditions, including creep, relaxation and cyclic loading, are presented. Results from parametric studies to determine the effects of various parameters on the process of degradation are reported. Finally, degradation of an annular cylinder subjected to pressure is also presented to mimic the effects of viscoelastic arterial walls (the outer cylinder) on the degradation response of a biodegradable stent (the inner cylinder). A general contact analysis is performed. As the stiffness of the biodegradable stent decreases, stress reduction in the stented viscoelastic arterial wall is observed. The integration of the proposed constitutive model with finite element software could help a designer to predict the time-dependent response of a biodegradable stent exhibiting finite deformation and under complex mechanical loading conditions. © 2012 Springer-Verlag Wien.

  11. Bleomycin induced urethral stricture in Hodgkin′s disease

    Directory of Open Access Journals (Sweden)

    Ritesh Tapkire

    2009-01-01

    Full Text Available Bleomycin is a glycoprotein that is extensively used in combination with other anti-cancer agents because of its relative lack of hematological and gastrointestinal toxicity. However, pulmonary toxicity is common with bleomycin and limits its therapeutic utility. Urethral stricture as a result of bleomycin toxicity has not been reported in literature. In this case report, a young male patient who developed urethral stricture after bleomycin-based chemotherapy is described and the possible effects of bleomycin on the urethra are discussed.

  12. [Urogenital bleeding revealing urethral prolapse in a prepubertal girl].

    Science.gov (United States)

    Ballouhey, Q; Abbo, O; Sanson, S; Cochet, T; Galinier, P; Pienkowski, C

    2013-06-01

    Urethral prolapse is a complete eversion of the distal urethral mucosa through the external meatus. It occurs primarily in prepubertal, primarly Black girls. Its pathophysiology has not been clearly identified. We report a case of a 5-year-old girl who came to the Emergency Department with a 1-day history of genital pain and "vaginal bleeding". Early recognition makes differential diagnosis with sexual abuse and staging allows prompt management under general anesthesic like prolapse reduction or surgical excision. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  13. Non-surgical treatment of primary female urethral cancer

    Directory of Open Access Journals (Sweden)

    Bernard F. Schneider

    2010-09-01

    Full Text Available Primary carcinomas of the female urethra are extremely rare, with an annual incidence of less than ten in one million. Currently, there is no consensus regarding management of this malignancy. However, there have been several case reports demonstrating the efficacy of chemoradiation in the treatment of female urethral cancer. In this report we present two cases of female primary urethral adenocar­cinoma that were treated by concomitant chemotherapy and external beam radiother­apy, followed by interstitial brachytherapy.

  14. A comparison of the temporary placement of 3 different self-expanding stents for the treatment of refractory benign esophageal strictures: a prospective multicentre study

    Directory of Open Access Journals (Sweden)

    Canena Jorge Manuel

    2012-06-01

    Full Text Available Abstract Background Refractory benign esophageal strictures (RBESs have been treated with the temporary placement of different self-expanding stents with conflicting results. We compared the clinical effectiveness of 3 types of stents: self-expanding plastic stents (SEPSs, biodegradable stents, and fully covered self-expanding metal stents (FCSEMSs, for the treatment of RBES. Methods This study prospectively evaluated 3 groups of 30 consecutive patients with RBESs who underwent temporary placement of either SEPSs (12 weeks, n = 10, biodegradable stents (n = 10 or FCSEMSs (12 weeks, n = 10. Data were collected to analyze the technical success and clinical outcome of the stents as evaluated by recurrent dysphagia, complications and reinterventions. Results Stent implantation was technically successful in all patients. Migration occurred in 11 patients: 6 (60% in the SEPS group, 2 (20% in the biodegradable group and 3 (30% in the FCSEMS group (P = 0.16. A total of 8/30 patients (26.6% were dysphagia-free after the end of follow-up: 1 (10% in the SEPS group, 3 (30% in the biodegradable group and 4 (40% in the FCSEMS group (P = 0.27. More reinterventions were required in the SEPS group (n = 24 than in the biodegradable group (n = 13 or the FCSEMS group (n = 13 (P = 0.24. Multivariate analysis showed that stricture length was significantly associated with higher recurrence rates after temporary stent placement (HR = 1.37; 95% CI = 1.08-1.75; P = 0.011. Conclusions Temporary placement of a biodegradable stent or of a FCSEMS in patients with RBES may lead to long-term relief of dysphagia in 30 and 40% of patients, respectively. The use of SEPSs seems least preferable, as they are associated with frequent stent migration, more reinterventions and few cases of long-term improvement. Additionally, longer strictures were associated with a higher risk of recurrence.

  15. Biodegradable Sonobuoy Decelerators

    Science.gov (United States)

    2015-06-01

    Standard Specification for Non-Floating Biodegradable Plastics in the Marine Environment. Results showed that no PHA grades were toxic to the marine...accordance with ASTM D6691 “Standard Test Method for Determining Aerobic Biodegradation of Plastics Materials in the Marine Environment by a Defined...the biodegradation of a polymer vs. a stand- alone weight loss test. Biodegradation rates as high as these are rare for plastics in the marine

  16. Biodegradable polymers: emerging excipients for the pharmaceutical and medical device industries.

    Directory of Open Access Journals (Sweden)

    Bhavesh Patel

    2013-12-01

    Full Text Available Worldwide many researchers are exploring the potential use of biodegradable polymerics as carriers for a wide range of therapeutic applications. In the past two decades, considerable progress has been made in the development of biodegradable polymeric materials, mainly in the biomedical and pharmaceutical industries due to their versatility, biocompatibility and biodegradability properties. The present review focuses on the use of biodegradable polymers in various therapeutic areas like orthopedic and contraceptive device, surgical sutures, implants, depot parenteral injections, etc. Biodegradable polymers have also contributed significantly to the development of drug-eluting stents (DES used for the treatment of obstructive coronary artery disease, such as angioplasty. Biodegradable synthetic polymers have potential applications in orthopedic device fixation due to properties that impact bone healing, formation, regeneration or substitution in the human body. The present review also emphasizes areas such as the chemistry of polymer synthesis, factors affecting the biodegradation, methods for the production of biodegradable polymer based formulations, the application of biodegradable polymers in dental implants, nasal drug deliveries, contraceptive devices, immunology, gene, transdermal, ophthalmic and veterinary applications, as well as, the sterilization of biodegradable based formulations and regulatory considerations for product filing.

  17. Urethral stone presenting as a stop valve--a rare complication of balanitis xerotica obliterans.

    Science.gov (United States)

    Dogra, P N; Singh, I; Khaitan, A

    2001-01-01

    Balanitis xerotic obliterans (BXO) is the genital subcategory of lichen sclerosis et atrophicus. The association of BXO with urethral stone causing interruption of the urinary stream and voiding by manual displacement of the urethral stone has not been described before. We describe one such case of a young boy with BXO and urethral stone who voided by manually displacing the stone for over a year. The case is reported to emphasize the ingenuity of the patient in continuing to void for over a year despite the association of the impacted urethral stone with urethral stricture and BXO.

  18. Biodegradable synthetic bone composites

    Science.gov (United States)

    Liu, Gao; Zhao, Dacheng; Saiz, Eduardo; Tomsia, Antoni P.

    2013-01-01

    The invention provides for a biodegradable synthetic bone composition comprising a biodegradable hydrogel polymer scaffold comprising a plurality of hydrolytically unstable linkages, and an inorganic component; such as a biodegradable poly(hydroxyethylmethacrylate)/hydroxyapatite (pHEMA/HA) hydrogel composite possessing mineral content approximately that of human bone.

  19. Ureteroscopic removal of forgotten ureteral stent

    Science.gov (United States)

    Kawahara, Takashi; Ishida, Hiroaki; Kubota, Yoshinobu; Matsuzaki, Junichi

    2012-01-01

    A 69-year-old female had a right ureteral stent placed due to ureteral stricture resulting from cervical cancer in March 2008. The ureteral stent migrated to the ureter and was not exchanged. A new ureteral stent was inserted, and was exchanged every 3 months. The patient was referred to our department to remove the forgotten ureteral stent. In January 2012, her old ureteral stent was removed ureteroscopically, and no ureteral stent encrustation was found. PMID:22707678

  20. Does PGA external stenting reduce compliance mismatch in venous grafts?

    Directory of Open Access Journals (Sweden)

    Zou Liang-jian

    2007-04-01

    Full Text Available Abstract Background Autogenous vein grafting is widely used in regular bypassing procedures. Due to its mismatch with the host artery in both mechanical property and geometry, the graft often over expands under high arterial blood pressure and forms a step-depth where eddy flow develops, thus causing restenosis, fibrous graft wall, etc. External stents, such as sheaths being used to cuff the graft, have been introduced to eliminate these mismatches and increase the patency. Although histological and immunochemical studies have shown some positive effects of the external stent, the mechanical mismatch under the protection of an external stent remains poorly analyzed. Methods In this study, the jugular veins taken from hypercholesterolemic rabbits were transplanted into the carotid arteries, and non-woven polyglycolic acid (PGA fabric was used to fabricate the external stents to study the effect of the biodegradable external stent. Eight weeks after the operation, the grafts were harvested to perform mechanical tests and histological examinations. An arc tangent function was suggested to describe the relationship between pressure and cross-sectional area to analyse the compliance of the graft. Results The results from the mechanical tests indicated that grafts either with or without external stents displayed large compliance in the low-pressure range and were almost inextensible in the high-pressure range. This was very different from the behavior of the arteries or veins in vivo. The data from histological tests showed that, with external stents, collagen fibers were more compact, whilst those in the graft without protection were looser and thicker. No elastic fiber was found in either kind of grafts. Furthermore, grafts without protection were over-expanded which resulted in much bigger cross-sectional areas. Conclusion The PGA external extent contributes little to the reduction of the mechanical mismatch between the graft and its host artery

  1. Delayed complications after flow-diverter stenting: reactive in-stent stenosis and creeping stents.

    Science.gov (United States)

    Cohen, José E; Gomori, John Moshe; Moscovici, Samuel; Leker, Ronen R; Itshayek, Eyal

    2014-07-01

    We assessed the frequency and severity of changes in stent configuration and location after the treatment of intracranial aneurysms, and patterns of in-stent stenosis. We retrospectively reviewed data for consecutive aneurysm patients managed with endovascular implantation of flow-diverter stents (Silk Flow Diverter [Balt Extrusion, Montmorency, France] and Pipeline Embolization Device [ev3/Coviden, Minneapolis, MN, USA]) from October 2011 to July 2012. Routine 2, 6, 9-12, and 16-20 month follow-up angiograms were compared, with a focus on changes in stent configuration and location from immediately after deployment to angiographic follow-up, and the incidence and development of in-stent stenosis. Thirty-four patients with 42 aneurysms met inclusion criteria. The Silk device was implanted in 16 patients (47%, single device in 15), the Pipeline device in 18 (53%, single device in 16). On first follow-up angiography, in-stent stenosis was observed in 38% of Silk devices and 39% of Pipeline devices. In-stent stenosis was asymptomatic in 12 of 13 patients. One woman presented with transient ischemic attacks and required stent angioplasty due to end tapering and mild, diffuse in-stent stenosis. Configuration and location changes, including stent creeping and end tapering were seen in 2/16 patients (13%) with Silk devices, and 0/18 patients with Pipeline devices. We describe stent creeping and end tapering as unusual findings with the potential for delayed clinical complications. In-stent stenosis, with a unique behavior, is a frequent angiographic finding observed after flow-diverter stent implant. The stenosis is usually asymptomatic; however, close clinical and angiographic monitoring is mandatory for individualized management. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Scrotal pop off in a congenital anterior urethral diverticulum.

    Science.gov (United States)

    Abrol, N; Deshpande, A V; Berry, C S; Devasia, A

    2014-08-01

    Congenital anterior urethral diverticulum is a rare entity. This teaching video shows the scrotal pop-off mechanism for an anterior urethral diverticulum and the unique voiding pattern of a boy who empties his bladder by compression of his scrotum. The findings during urethroscopy and open reconstruction are also demonstrated. A four-year-old boy presented to the clinic with a poor urinary stream and scrotal swelling during voiding. Physical examination during voiding revealed a dumbbell-shaped anterior urethral diverticulum with scrotal pop off and preserved renal function. Open excision of the scrotal part of diverticulum was performed. Urethroplasty was conducted using a de-epithelialised diverticular wall flap from the penobulbar urethra. On follow up the boy voided with a good flow and resolution of symptoms. Scrotal pop off with completion of voiding by manual compression of the diverticulum may preserve bladder and renal function. The preferred treatment of anterior urethral diverticulum is open excision of the diverticulum and reconstruction. The wall of the diverticulum may be used to reinforce the repair ventrally, where the corpus spongiosum is deficient. Copyright © 2014 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.

  3. Surgical Management of Prepubertal Urethral Prolapse: A report of 3 ...

    African Journals Online (AJOL)

    dell

    Department of Surgery, Lagos State University College of Medicine and Teaching ... Methods: Our series of 3 cases all presented with vaginal bleeding and all had primary ... Parents, caregivers and medical personnel in our ... recognition of urethral prolapse avoids unnecessary investigation and anxiety for the patients.

  4. Treatment of urethral strictures with balloon dilation: A forgotten tale

    Directory of Open Access Journals (Sweden)

    Konstantinos Stamatiou

    2015-09-01

    Full Text Available Urethral stricture is a common condition that can lead to serious complications such as urinary infections and renal insufficiency secondary to urinary retention. Treatment options include catheterization and dilation, urethroplasty and endoscopic internal urethrotomy as well. Although treatment option depends on the type, length and aetiology of stricture, the choice can be influenced to varying degrees by the simplicity of the method, the preferences of the patient the available accoutrements and the patient health condition. Both urethroplasty and endoscopic internal urethrotomy require anaesthesia and thus are not suitable for many elder and unfit for surgical treatment patients. On the other hand, dilations are easy to perform in every day clinical practice however they have been associated with iatrogenic urethral trauma. In contrast, balloon dilation under vision dilates by radial application of forces against the stricture, avoiding the potentially shearing forces associated with sequential rigid dilation. Since it reduces the possibility of an iatrogenic urethral trauma and the subsequent spongiofibrosis may lead into improved therapeutic outcomes. In this report we describe a technique for the treatment of urethral strictures with balloon dilation in elder and unfit for surgical treatment patients.

  5. Prostatic urethral lift vs transurethral resection of the prostate

    DEFF Research Database (Denmark)

    Gratzke, Christian; Barber, Neil; Speakman, Mark J

    2017-01-01

    OBJECTIVES: To compare prostatic urethral lift (PUL) with transurethral resection of the prostate (TURP) with regard to symptoms, recovery experience, sexual function, continence, safety, quality of life, sleep and overall patient perception. PATIENTS AND METHODS: A total of 80 patients with lower...

  6. Rosoxacin in the treatment of uncomplicated acute gonococcal urethritis.

    Directory of Open Access Journals (Sweden)

    Vagaskar S

    1990-10-01

    Full Text Available A total of 112 male patients presenting with acute gonococcal urethritis were admitted to the hospital. The diagnosis was confirmed by smear, culture, oxidase reaction and sugar fermentation tests. The patients were treated with a single 300 mg capsule of rosoxacin. All patients except one showed adequate response to rosoxacin.

  7. Pudendal nerve stimulation induces urethral contraction and relaxation

    NARCIS (Netherlands)

    J. le Feber (Joost); E. van Asselt (Els)

    1999-01-01

    textabstractIn this study we measured urethral pressure changes in response to efferent pudendal nerve stimulation in rats. All other neural pathways to the urethra were transected, and the urethra was continuously perfused. We found fast twitch-like contractions, super

  8. Passive urethral resistance to dilation in healthy women

    DEFF Research Database (Denmark)

    Bagi, P; Thind, P; Nordsten, M

    1995-01-01

    at equilibrium, P alpha and P beta express the decline in pressure, and tau alpha and tau beta are time constants. The size of the pressure response proved highly dependent on velocity and size of dilation as well as urethral site of measurement, with the maximum values in the high pressure zone. The time...

  9. Management of anterior urethral strictures with buccal mucosa: Our ...

    African Journals Online (AJOL)

    Abdelwahab Elkassaby

    2016-03-02

    Mar 2, 2016 ... different uses of buccal mucosal graft as a reconstructive and replacement tool for anterior urethral .... of excessive mobilization and penile curvature. ... established that a strip of penile skin would inevitably form a tube if left in ...

  10. Urethral catheterization:The need for adequate undergraduate exposure

    Directory of Open Access Journals (Sweden)

    E.V. Ezenwa

    2017-03-01

    Conclusion: Newly recruited interns have poor practical exposure to urethral catheterization. Efforts should be made to improve the quality of supervised training given to medical undergraduates so as to avoid complications that could arise if this procedure is not properly done when they qualify.

  11. A Method for Recording Urethral Pressure Profiles in Female Rats.

    Directory of Open Access Journals (Sweden)

    Shengfei Xu

    Full Text Available Urethral pressure profile (UPP and leak-point pressure (LPP measurements as well as external urethral sphincter (EUS electromyography (EMG and videourodynamic analyses are the primary methods for evaluating urethral function in humans. However, UPP recording in female rats, a widely used animal model, is challenging due to their small body sizes. This study reports a novel method for recording UPP in female rats.Seventeen anesthetized female rats were studied. LPP data for 14 rats were included. The other 3 rats were excluded because of death or abnormal urogenital organs. UPP curves were recorded using a modified water-perfusion catheter system, with the lateral hole facing the 3-, 6-, 9-, and 12-o'clock positions in a randomized sequence. LPP, functional urethral length (FUL and maximum urethral closure pressure (MUCP were analyzed.The mean LPP was 64.39 ± 20.29 cm H2O. The mean FUL and MUCP values at the 3-, 6-, 9-, and 12-o'clock positions were 12.90 ± 1.20, 16.70 ± 1.95, 13.90 ± 2.42, and 11.60 ± 0.97 mm, respectively, and 38.70 ± 11.85, 33.90 ± 11.82, 37.40 ± 11.95, and 71.90 ± 23.01 cm H2O, respectively. The FUL at the 6-o'clock position and MUCP at the 12-o'clock position were significantly greater than those at the other 3 positions. The FUL and MUCP of repeated UPP recordings were not significantly different than those of the first recordings.UPP recording using a modified method based on a water-perfusion catheter system is feasible and replicable in female rats. It produces UPP curves that sensitively and appreciably reflect detailed pressure changes at different points within the urethra and thus provides opportunity to evaluate urethral structures, especially the urethral sphincter, in detail. These results may enhance the utility of female rat models in research of urinary sphincter mechanisms.

  12. Urethral catheter insertion forces: a comparison of experience and training

    Directory of Open Access Journals (Sweden)

    Benjamin K. Canales

    2009-02-01

    Full Text Available Purpose: This study was undertaken to evaluate the insertion forces utilized during simulated placement of a urethral catheter by healthcare individuals with a variety of catheter experience. Materials and Methods: A 21F urethral catheter was mounted to a metal spring. Participants were asked to press the tubing spring against a force gauge and stop when they met a level of resistance that would typically make them terminate a catheter placement. Simulated catheter insertion was repeated fives times, and peak compression forces were recorded. Healthcare professionals were divided into six groups according to their title: urology staff, non-urology staff, urology resident/ fellow, non-urology resident/ fellow, medical student, and registered nurse. Results: A total of fifty-seven healthcare professionals participated in the study. Urology staff (n = 6 had the lowest average insertion force for any group at 6.8 ± 2.0 Newtons (N. Medical students (n = 10 had the least amount of experience (1 ± 0 years and the highest average insertion force range of 10.1 ± 3.7 N. Health care workers with greater than 25 years experience used significantly less force during catheter insertions (4.9 ± 1.8 N compared to all groups (p < 0.01. Conclusions: We propose the maximum force that should be utilized during urethral catheter insertion is 5 Newtons. This force deserves validation in a larger population and should be considered when designing urethral catheters or creating catheter simulators. Understanding urethral catheter insertion forces may also aid in establishing competency parameters for health care professionals in training.

  13. Angioplasty and stent - heart - discharge

    Science.gov (United States)

    Drug-eluting stents - discharge; PCI - discharge; Percutaneous coronary intervention - discharge; Balloon angioplasty - discharge; Coronary angioplasty - discharge; Coronary artery angioplasty - discharge; Cardiac ...

  14. [Biodegradation of polyethylene].

    Science.gov (United States)

    Yang, Jun; Song, Yi-ling; Qin, Xiao-yan

    2007-05-01

    Plastic material is one of the most serious solid wastes pollution. More than 40 million tons of plastics produced each year are discarded into environment. Plastics accumulated in the environment is highly resistant to biodegradation and not be able to take part in substance recycle. To increase the biodegradation efficiency of plastics by different means is the main research direction. This article reviewed the recent research works of polyethylene biodegradation that included the modification and pretreatment of polyethylene, biodegradation pathway, the relevant microbes and enzymes and the changes of physical, chemical and biological properties after biodegradation. The study directions of exploiting the kinds of life-forms of biodegradation polyethylene except the microorganisms, isolating and cloning the key enzymes and gene that could produce active groups, and enhancing the study on polyethylene biodegradation without additive were proposed.

  15. Nasal packing and stenting

    Directory of Open Access Journals (Sweden)

    Weber, Rainer K.

    2009-01-01

    Full Text Available Nasal packs are indispensable in ENT practice. This study reviews current indications, effectiveness and risks of nasal packs and stents. In endoscopic surgery, nasal packs should always have smooth surfaces to minimize mucosal damage, improve wound healing and increase patient comfort. Functional endoscopic endonasal sinus surgery allows the use of modern nasal packs, since pressure is no longer required. So called hemostatic/resorbable materials are a first step in this direction. However, they may lead to adhesions and foreign body reactions in mucosal membranes. Simple occlusion is an effective method for creating a moist milieu for improved wound healing and avoiding dryness. Stenting of the frontal sinus is recommended if surgery fails to produce a wide, physiologically shaped drainage path that is sufficiently covered by intact tissue.

  16. In vitro hemocompatibility and cytocompatibility of dexamethasone-eluting PLGA stent coatings

    Science.gov (United States)

    Zhang, Jiang; Liu, Yang; Luo, Rifang; Chen, Si; Li, Xin; Yuan, Shuheng; Wang, Jin; Huang, Nan

    2015-02-01

    Drug-eluting stents (DESs) have been an important breakthrough for interventional cardiology applications since 2002. Though successful in reducing restenosis, some adverse clinical problems still emerged, which were mostly caused by the bare-metal stents and non-biodegradable polymer coatings, associated with the delayed endothelialization process. In this study, dexamethasone-loaded poly (lactic-co-glycolic acid) (PLGA) coatings were developed to explore the potential application of dexamethasone-eluting stents. Dexamethasone-eluting PLGA stents were prepared using ultrasonic atomization spray method. For other tests like stability and cytocompatibility and hemocompatibility tests, dexamethasone loaded coatings were deposited on 316L SS wafers. Fourier transform-infrared spectroscopy (FT-IR) results demonstrated that there was no chemical reaction between PLGA and dexamethasone. The balloon expansion experiment and surface morphology observation suggested that the stent coatings were smooth and uniform, and could also withstand the compressive and tensile strains imparted without cracking after stent expansion. The drug release behavior in vitro indicated that dexamethasone existed burst release within 1 day, but it presented linear release characteristics after 6 days. In vitro platelets adhesion, activation test and APTT test were also done, which showed that after blending dexamethasone into PLGA, the hemocompatibility was improved. Besides, dexamethasone and dexamethasone-loaded PLGA coatings could significantly inhibit the attachment and proliferation of smooth muscle cells.

  17. EFFECTIVENESS OF TRANSPU B IC URETHROPLASTY FOR RECURRENT URETHRAL STR U CTURE IN PELVIC FRACTURE URETHRAL DISTRACTION DEFECT

    Directory of Open Access Journals (Sweden)

    Mudegowdar

    2015-08-01

    Full Text Available AIM OF THE STUDY: Effectiveness of Transpubic urethroplasty in recurrent (failed urethral strictures due to pelvic fracture urethral distraction defects. INTRODUCTION: Urethral distraction injuries occur upto 10% of pelvic fracture cases. The principle indication of Transpubic urethroplasty is length >3 c ms, recur rent (failed repairs of posterior urethral stricture. Though other procedures like primary anastomotic urethroplasty, rerouting of the urethra under the corporal body, urethral substitution with tubularised flaps, two stage urethroplasty are described, Tr anspubic urethroplasty is said to produce the best results especially when repeat procedures are required. MATERIALS & METHODS: This is a prospective study from 2004 to 2014 consisting of 17 patients having recurrent stricture urethra secondary to pelvic f racture urethral distraction defects (PFUDD. All the patients were males and their age ranged from 15year to 45 years. Pre - op evaluation included X - ray KUB, Ultrasound abdomen & pelvis, retrograde urethrogram (RGU, micturating cystourethrogram (MCU, up and down Cystoscopy, urine culture and renal biochemical parameters. Urethra was approched through progressive perineal and abdominal approach with total pubectomy, followed by excising fibrosed stricture and tension free end to end anastomosis. Post opera tively pericatheteral RGU was carried out after 4 weeks and Catheter removed if there was no leak. RGU, MCU uroflowmetry and PVR were done one month after removal of catheter. Subsequently UFR, PVR and obstructive symptoms were assessed periodically. RESUL TS: All 17 Cases were followed up for a period of 3 - 11 years. Out of 17patients, 14(80% patients maintained good uroflow (UFR and insignificant PVR and procedure was considered successful. In 3 patients procedure failed, of which 2 patients had pericathe ter leak and reduced urinary flow with significant PVR and were followed up with CIC and 1 patient remained on permanent

  18. Carotid artery stenting: which stent for which lesion?

    Science.gov (United States)

    Bosiers, Marc; Deloose, Koen; Verbist, Jürgen; Peeters, Patrick

    2005-01-01

    The different geometries and working principles of carotid stents (nitinol or cobalt chromium, open- or closed-cell configuration) provide each product with unique functional properties. The individual characteristics of each device may make it an attractive choice in one circumstance but render it less desirable in other situations. In approximately 75% of all procedures, all types of stents will achieve similar outcomes, making adequate device selection unnecessary. For the remaining quarter, careful preoperative screening is mandatory. In addition to eventual access issues, the choice of the optimal carotid stent depends mainly on arterial anatomy and lesion morphology. When treating a tortuous anatomy, stents with a flexible and comformable open-cell configuration are preferred. In arteries with a significant mismatch between common carotid artery and internal carotid artery diameter, cobalt chromium (Elgiloy) or tapered nitinol stents are selected. Lesions with suspected high emboligenicity are best covered with stents with a closed-cell configuration, whereas highly calcified lesions need treatment with nitinol stents. Thorough knowledge of the characteristics, advantages and disadvantages, and working principles of the different available stents is mandatory to optimally select the materials to be used for patients eligible for carotid revascularization.

  19. Hemodynamics in Idealized Stented Coronary Arteries: Important Stent Design Considerations.

    Science.gov (United States)

    Beier, Susann; Ormiston, John; Webster, Mark; Cater, John; Norris, Stuart; Medrano-Gracia, Pau; Young, Alistair; Cowan, Brett

    2016-02-01

    Stent induced hemodynamic changes in the coronary arteries are associated with higher risk of adverse clinical outcome. The purpose of this study was to evaluate the impact of stent design on wall shear stress (WSS), time average WSS, and WSS gradient (WSSG), in idealized stent geometries using computational fluid dynamics. Strut spacing, thickness, luminal protrusion, and malapposition were systematically investigated and a comparison made between two commercially available stents (Omega and Biomatrix). Narrower strut spacing led to larger areas of adverse low WSS and high WSSG but these effects were mitigated when strut size was reduced, particularly for WSSG. Local hemodynamics worsened with luminal protrusion of the stent and with stent malapposition, adverse high WSS and WSSG were identified around peak flow and throughout the cardiac cycle respectively. For the Biomatrix stent, the adverse effect of thicker struts was mitigated by greater strut spacing, radial cell offset and flow-aligned struts. In conclusion, adverse hemodynamic effects of specific design features (such as strut size and narrow spacing) can be mitigated when combined with other hemodynamically beneficial design features but increased luminal protrusion can worsen the stent's hemodynamic profile significantly.

  20. Nobori-Biolimus-Eluting Stents versus Resolute Zotarolimus-Eluting Stents in Patients Undergoing Coronary Intervention: A Propensity Score Matching

    Science.gov (United States)

    Tantawy, Ayman; Ahn, Chul-Min; Shin, Dong-Ho; Kim, Jung-Sun; Kim, Byeong-Keuk; Ko, Young-Guk; Choi, Donghoon; Jang, Yangsoo

    2017-01-01

    Purpose To compare the 1-year outcomes of a durable polymer Zotarolimus-eluting stent (ZES) versus a biodegradable polymer Biolimus-eluting stent (BES) in patients undergoing percutaneous coronary intervention. Materials and Methods A total of 2083 patients from 2 different registries, 1125 treated with BES in NOBORI registry and 858 received ZES in CONSTANT registry were included in this study. Clinical outcomes were compared with the use of propensity score matching (PSM). The primary endpoint was a composite of major adverse cardiovascular and cerebrovascular events (MACCEs) including cardiac death, myocardial infarction, clinically driven target lesion revascularization and stroke. Secondary end points were individual components of MACCEs as well as the incidence of stent thrombosis at 1-year follow-up. Results After PSM, 699 matched pairs of patients (n=1398) showed no significant difference between BES and ZES in the risk of composite MACCEs at 1 year (2.6% vs. 1.7%; p=0.36). Cardiac death was not statistically different between groups (0.7% vs. 0.4%, p=0.73). Target lesion revascularization rate was also similar between BES and ZES (1.1% vs. 0.7%, p=0.579). Non-Q wave myocardial infarction, as well as target-vessel revascularization rate, was similar between the two groups (0.14% for BES and 0.72% for ZES). Both stent types were excellent with no cases of stent thrombosis and rate of Q wave myocardial infarction reported during the follow-up period. Conclusion In this cohort of patients treated with BES or ZES, the rate of MACCEs at 1 year was low and significantly not different between both groups. PMID:28120558

  1. Heparin-Coated Coronary Stents.

    Science.gov (United States)

    van Der Giessen WJ; van Beusekom HM; Larsson; Serruys

    1999-09-01

    The development of the heparin-coated (HC)-stent should be viewed against the backdrop of the early unfavorable results with noncoated stents in the pre-intravascular ultrasound and pre-ticlopidine era. Notwithstanding, results of pilot and randomized trials show a surprisingly low incidence of (sub)acute stent thrombosis under challenging circumstances, such as acute coronary syndromes. Considering the quite low incidence of early complications with noncoated second-generation stents, it may require large trials to prove the clinical efficacy of the heparin- coating against noncoated devices. However, even if the "added value" of the heparin-coating will never be clinically proven, it has helped to enhance the penetration of stent therapy in interventional cardiology. Unlike the situation in 1992, very few cardiologists will now disagree with the statement that stents contribute to the state-of-the-art treatment of patients with angina pectoris or acute myocardial infarction. A preliminary comparison of available trials also suggests that the heparin-coated Palmaz-Schatz stent (Cordis Corp., Waterloo, Belgium) is as effective as the noncoated stent plus abciximab treatment.

  2. A new removable airway stent

    Directory of Open Access Journals (Sweden)

    Tore Amundsen

    2016-09-01

    Full Text Available Background: Malignant airway obstruction is a feared complication and will most probably occur more frequently in the future because of increasing cancer incidence and increased life expectancy in cancer patients. Minimal invasive treatment using airway stents represents a meaningful and life-saving palliation. We present a new removable airway stent for improved individualised treatment. Methods: To our knowledge, the new airway stent is the world's first knitted and uncovered self-expanding metal stent, which can unravel and be completely removed. In an in vivo model using two anaesthetised and spontaneously breathing pigs, we deployed and subsequently removed the stents by unravelling the device. The procedures were executed by flexible bronchoscopy in an acute and a chronic setting – a ‘proof-of-principle’ study. Results: The new stent was easily and accurately deployed in the central airways, and it remained fixed in its original position. It was easy to unravel and completely remove from the airways without clinically significant complications. During the presence of the stent in the chronic study, granulation tissue was induced. This tissue disappeared spontaneously with the removal. Conclusions: The new removable stent functioned according to its purpose and unravelled easily, and it was completely removed without significant technical or medical complications. Induced granulation tissue disappeared spontaneously. Further studies on animals and humans are needed to define its optimal indications and future use.

  3. Stents for malignant ureteral obstruction

    Directory of Open Access Journals (Sweden)

    Kristina Pavlovic

    2016-07-01

    Full Text Available Malignant ureteral obstruction can result in renal dysfunction or urosepsis and can limit the physician's ability to treat the underlying cancer. There are multiple methods to deal with ureteral obstruction including regular polymeric double J stents (DJS, tandem DJS, nephrostomy tubes, and then more specialized products such as solid metal stents (e.g., Resonance Stent, Cook Medical and polyurethane stents reinforced with nickel-titanium (e.g., UVENTA stents, TaeWoong Medical. In patients who require long-term stenting, a nephrostomy tube could be transformed subcutaneously into an extra-anatomic stent that is then inserted into the bladder subcutaneously. We outline the most recent developments published since 2012 and report on identifiable risk factors that predict for failure of urinary drainage. These failures are typically a sign of cancer progression and the natural history of the disease rather than the individual type of drainage device. Factors that were identified to predict drainage failure included low serum albumin, bilateral hydronephrosis, elevated C-reactive protein, and the presence of pleural effusion. Head-to-head studies show that metal stents are superior to polymeric DJS in terms of maintaining patency. Discussions with the patient should take into consideration the frequency that exchanges will be needed, the need for externalized hardware (with nephrostomy tubes, or severe urinary symptoms in the case of internal DJS. This review will highlight the current state of diversions in the setting of malignant ureteral obstruction.

  4. Randomized comparison of a sirolimus-eluting Orsiro stent with a biolimus-eluting Nobori stent in patients treated with percutaneous coronary intervention

    DEFF Research Database (Denmark)

    Jensen, Lisette Okkels; Thayssen, Per; Maeng, Michael

    2015-01-01

    -coating releasing sirolimus from a biodegradable polymer (O-SES, Orsiro; Biotronik, Bülach, Switzerland) with the stainless steel biodegradable polymer biolimus-eluting Nobori stents (N-BES, Nobori; Terumo, Tokyo, Japan) in an all-comer patient population. DESIGN: The multicenter SORT OUT VII trial (NCT01879358......) randomly assigned 2,530 patients to treatment with biodegradable polymer O-SES or biodegradable polymer N-BES at 3 sites in Western Denmark. Patients were eligible, if they were ≥18 years old; had chronic stable coronary artery disease or acute coronary syndromes; and ≥1 coronary lesion with >50% diameter...... will be used. An event rate of 6.5% is assumed in each stent group. With a sample size of 1,157 patients in each treatment arm, a 2-group large-sample normal approximation test of proportions with a 1-sided 5% significance level will have 90% power to detect noninferiority of the O-SES compared with the N...

  5. Incidence of definite stent thrombosis or in-stent restenosis after drug-eluting stent implantation for treatment of coronary in-stent restenosis

    DEFF Research Database (Denmark)

    Jensen, Jesper Khedri; Jensen, Lisette Okkels; Terkelsen, Christian Juhl;

    2013-01-01

    There are limited data on the optimal management of in-stent restenosis after percutaneous coronary intervention (PCI) with bare metal stent (BMS) or drug-eluting stent (DES) implantations. We assessed the clinical presentation, the incidence, and prognosis of definite stent thrombosis...

  6. [Longitudinal stent deformation during bifurcation lesion treatment].

    Science.gov (United States)

    Mami, Z; Monsegu, J

    2014-12-01

    Longitudinal stent deformation is defined as a compression of stent length after its implantation. It's a rare complication but dangerous seen with several stents. We reported a case of longitudinal stent deformation during bifurcation lesion treatment with a Promus Element(®) and we perform a short review of this complication.

  7. Development of epigallocatechin gallate-eluting polymeric stent and its physicochemical, biomechanical and biological evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Han, Dong-Wook [Department of Nanomedical Engineering, College of Nanoscience and Nanotechnology, Pusan National University, Busan 609-735 (Korea, Republic of); Lee, Jun Jae [Division of Advanced Fibro-Science, Kyoto Institute of Technology, Kyoto 606-8585 (Japan); Jung, Duk-Young [Senior Products Industrial Center, Busan Techno-Park, Busan-617-030 (Korea, Republic of); Park, Jong-Chul [Cellbiocontrol Laboratory, Department of Medical Engineering, Yonsei University College of Medicine, Seoul 120-752 (Korea, Republic of); Hyon, Suong-Hyu, E-mail: nanohan@pusan.ac.k, E-mail: biogen@frontier.kyoto-u.ac.j [Department of Medical Simulation Engineering, Institute for Frontier Medical Sciences, Kyoto University, Kyoto 606-8507 (Japan)

    2009-08-15

    Localized drug delivery from drug-eluting stents has been accepted as one of the most promising treatment methods for preventing restenosis after stenting. However, hypersensitivity reactions caused by their nonresorbable polymer coatings and bare-metal stents may result in serious clinical sequelae. Epigallocatechin-3-O-gallate (EGCG), the predominant catechin from tea, has been shown to exert anti-thrombotic, anti-inflammatory and anti-proliferative activities. In this study, it was hypothesized that sustainedly released EGCG from biodegradable poly(lactide-co-epsilon-caprolactone, PLCL) would suppress the proliferation of vascular smooth muscle cells (VSMCs). EGCG-releasing PLCL (E-PLCL) was prepared by blending PLCL with EGCG. The surface morphology, roughness and melting temperature of PLCL were not changed despite EGCG addition. EGCG was uniformly dispersed into E-PLCL and sustainedly released for periods up to 7 days by controlled diffusion rather than PLCL degradation. Moreover, EGCG did not affect tensile strength at break, but significantly increased the elastic modulus of PLCL. The proliferation of VSMCs onto E-PLCL was significantly suppressed although the cell attachment onto E-PLCL had been higher than that onto PLCL. On the other hand, EGCG-eluting polymeric stents were prepared with neither cracks nor webbings between struts, and their structural integrity was maintained without delamination or destruction. These results suggest that E-PLCL can be potentially applied for fabricating an EGCG-eluting vascular stent, namely an EGCG-eluting polymeric stent, or even an EGCG-releasing polymer-coated metal stent, to prevent thrombosis, inflammation and in-stent restenosis.

  8. Role of tissue engineered buccal mucosa for treatment of urethral stricture

    Directory of Open Access Journals (Sweden)

    Vaddi S

    2013-10-01

    Full Text Available Cell based therapies in Urology: Cell based therapy for tissue engineering in urology, like in other branches of medicine uses the principles of cell transplantation, materials science, and biomedical engineering to develop biologic substitutes that can restore and maintain function of the damaged or lost genitourinary organs. Most current strategies for tissue engineering depend on a sample of autologous cells from the diseased organ of the host. However in cases where primary autologous cells cannot be expanded, pluripotent stem cells are an ideal source. Biomaterials play a major role in genitourinary tissue engineering. They are used to replace biologic and mechanical functions of the native extracellular matrix. Three classes of biomaterials have been used for the engineering of genitourinary tissues: naturally derived materials, such as collagen and alginate; acellular tissue matrices, such as bladder submucosa and synthetic polymers, such as polyglycolic acid [1]. A lot of research is ongoing in urethral regeneration by tissue engineering and cell based therapy. Tubularized collagen matrices seeded with autologous cells are used to regenerate the urethra [2]. Urinary Bladder reconstruction is possible with bladder shaped biodegradable scaffold seeded with autologous urothelial cells and smooth muscle cells [3]. Ureteral acellular tubular grafts have been used to replace ureteral loss but with poor functional results [4]. Cell-seeded biodegradable polymer scaffolds have been used with more success to reconstruct ureteral tissues [3]. The kidney is the most challenging organ in the genitourinary system to reconstruct because of its complex structure and function. Cell based therapies are used for creation of functional renal structures in vivo. Renal tubular cells have been harvested, expanded in culture and seeded on to a tubular device to function as nephron [5]. The expansion of this system to larger three-dimensional structures is the

  9. Urethral pressure reflectometry in women with pelvic organ prolapse

    DEFF Research Database (Denmark)

    Khayyami, Yasmine; Lose, Gunnar; Klarskov, Niels

    2017-01-01

    INTRODUCTION AND HYPOTHESIS: The mechanism of continence in women with pelvic organ prolapse (POP) before and after surgery remains unknown. Urethral pressure reflectometry (UPR) separates women with stress urinary incontinence (SUI) from continent women by measuring urethral opening pressure...... at an abdominal pressure of 50 cmH2O (P O-Abd 50). UPR can help identify women with POP at risk of postoperative de novo SUI. The aim of this study was to investigate the reproducibility of UPR in women with POP. METHODS: Women with anterior or posterior vaginal wall prolapse were recruited for this prospective...... to determine the level of agreement between measurements. Paired t tests were used to estimate the difference; a two-tailed P value of prolapse and 11 women with posterior vaginal wall prolapse. There were...

  10. Aphallia with urethrorectal fistula, bladder and urethral calculi

    Directory of Open Access Journals (Sweden)

    M Movarrekh

    2006-04-01

    Full Text Available Introduction: Aphallia is a very rare urogenital anomaly with incidence rate of 1 in 30,000,000. It usually coexists with other anomalies such as cardiovascular anomalies which are incompatible with normal life, and therefore infants are delivered stillbirth or live for a very short period of time. Methods: We present an 18 months old boy with aphallia associated with congenital urethrorectal fistula, bladder and urethral stones. All stones were removed endourologically, recto-urethral fistula was repaired and perincal urethrostomy was performed. Results: The stones were composed of calcium phosphate colonized by klebiella pneumonia and proteus mirabilis. Urethrorectal fistula repairment was confirmed by cystography. Patient was discharged without a urinary catheter. Conclusion: In developed countries, management of such patients is to raise them as females. However, we must consider socio-cultural conditions, parents preference and patients tendency in management of aphallia.

  11. Study on acupuncture and moxibustion therapy for female urethral syndrome.

    Science.gov (United States)

    Zheng, H; Wang, S; Shang, J; Chen, G; Huang, C; Hong, H; Chen, S

    1998-06-01

    Among 180 patients with female urethral syndrome, 128 were treated by acupuncture and moxibustion and 52 by western medicine as controls. The short-term effective rate in the acupuncture and moxibustion group was 90.6% and the long-term effective rate, 80.4%; whereas the short-term effective rate of the control group was 26.9% (P acupuncture and moxibustion treatment (P 0.05). Sixty-nine cases from the acupuncture and moxibustion group and 39 from the control group were subjected before and after treatment to determinations of the maximal bladder pressure, maximal abdominal pressure, bladder-neck pressure, and maximal urethral closure pressure during urination. All these indexes were decreased remarkably in the acupuncture and moxibustion group, while no changes were observed in the control group.

  12. Brachytherapy on urethral carcinoma; Braquiterapia no carcinoma da uretra

    Energy Technology Data Exchange (ETDEWEB)

    Novaes, Paulo Eduardo R.S. [Fundacao Antonio Prudente, Sao Paulo, SP (Brazil). Hospital A.C. Camargo. Dept. de Radioterapia

    1996-04-01

    From 1954 to 1992 21 patients with primary urethral carcinoma were attended at A.C.Camargo Hospital - Fundacao Antonio Prudente - Sao Paulo. There were 17 female and 4 male with a median age of 58 years old. Eight patients received surgery, 8 radiation therapy and 5 were treated with palliative intention or were not treated. Patients treated by radiotherapy received 60 Gy to 80 Gy. Three patients were submitted to exclusive brachytherapy, 4 to the association of external beam and brachytherapy and 1 to external radiotherapy. Interstitial techniques were employed in 5 patients and intraluminal brachytherapy with special applicator in 2. Seven of 8 patients (87.5%) had local control and disease free survival with a minimum follow-up 4 years. Late effects were not observed. Primary urethral carcinoma is a curable disease by radiotherapy and the association of external irradiation and brachytherapy is the ideal approach. (author) 11 refs.

  13. Urethral tissue regeneration using collagen scaffold modified with collagen binding VEGF in a beagle model.

    Science.gov (United States)

    Jia, Weisheng; Tang, He; Wu, Jianjian; Hou, Xianglin; Chen, Bing; Chen, Wei; Zhao, Yannan; Shi, Chunying; Zhou, Feng; Yu, Wei; Huang, Shengquan; Ye, Gang; Dai, Jianwu

    2015-11-01

    Extensive urethral defects have a serious impact on quality of life, and treatment is challenging. A shortage of material for reconstruction is a key limitation. Improving the properties of biomaterials and making them suitable for urethral reconstruction will be helpful. Previously, we constructed a fusion protein, collagen-binding VEGF (CBD-VEGF), which can bind to collagen scaffold, stimulate cell proliferation, and promote angiogenesis and tissue regeneration. We proposed that CBD-VEGF could improve the performance of collagen in reconstruction of extensive urethral defects. Our results showed that collagen scaffolds modified with CBD-VEGF could promote urethral tissue regeneration and improve the function of the neo-urethra in a beagle extensive urethral defect model. Thus, modifying biomaterials with bioactive factors provides an alternative strategy for the production of suitable biomaterials for urethral reconstruction.

  14. Acquired urethral diverticulum in a man with paraplegia presenting with a scrotal mass: a case report

    Directory of Open Access Journals (Sweden)

    El Ammari Jalal Eddine

    2012-11-01

    Full Text Available Abstract Introduction Male urethral diverticula are rare. Patients with paraplegia may present with acquired diverticula as a result of prolonged catheterization. Diverticula may be asymptomatic or lead to lower urinary tract symptoms. Rarely, the diverticulum may initially present as a scrotal mass. Case presentation We report the case of a male 45-year-old Arab with paraplegia who presented with a mass in the peno-scrotal junction. He had in his medical history iterative prolonged urethral catheterizations associated with urine leakage through the urethral meatus upon applying compression. Diagnosis confirmation of urethral diverticula is obtained by retrograde urethrography. The patient underwent a diverticulectomy with urethroplasty. Conclusion Male acquired urethral diverticula can be found in patients who have a spinal cord injury because of prolonged urethral catheterization. Clinical presentations are different and sometimes can be misleading. Retrograde urethrography is the key to diagnosis and open surgery is the treatment of reference.

  15. Biodegradability of plastics.

    Science.gov (United States)

    Tokiwa, Yutaka; Calabia, Buenaventurada P; Ugwu, Charles U; Aiba, Seiichi

    2009-08-26

    Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  16. Polymer material biodegradation

    Directory of Open Access Journals (Sweden)

    B. Grabowska

    2010-04-01

    Full Text Available Data from literature was used to discuss the impact of external factors (stress, radiation, temperature, ultrasounds, biological organisms on the course of polymer material degradation. Polymer materials, in widespread use for over a dozen years, constitute a serious environmental problem. This is why their susceptibility to biodegradation is researched. Work on biodegradable polymers concernsmodifying their structure to bring their physical and chemical properties closer to plastics in practical use or using biodegradable polymers as an alternative for the current conventional materials. In addition, the publication also presents the first results of work on the biodegradation of polymer foundry binders.

  17. Biodegradability of Plastics

    Directory of Open Access Journals (Sweden)

    Yutaka Tokiwa

    2009-08-01

    Full Text Available Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.. In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.

  18. Cholinergic urethral brush cells are widespread throughout placental mammals.

    Science.gov (United States)

    Deckmann, Klaus; Krasteva-Christ, Gabriela; Rafiq, Amir; Herden, Christine; Wichmann, Judy; Knauf, Sascha; Nassenstein, Christina; Grevelding, Christoph G; Dorresteijn, Adriaan; Chubanov, Vladimir; Gudermann, Thomas; Bschleipfer, Thomas; Kummer, Wolfgang

    2015-11-01

    We previously identified a population of cholinergic epithelial cells in murine, human and rat urethrae that exhibits a structural marker of brush cells (villin) and expresses components of the canonical taste transduction signaling cascade (α-gustducin, phospholipase Cβ2 (PLCβ2), transient receptor potential cation channel melanostatin 5 (TRPM5)). These cells serve as sentinels, monitoring the chemical composition of the luminal content for potentially hazardous compounds such as bacteria, and initiate protective reflexes counteracting further ingression. In order to elucidate cross-species conservation of the urethral chemosensory pathway we investigated the occurrence and molecular make-up of urethral brush cells in placental mammals. We screened 11 additional species, at least one in each of the five mammalian taxonomic units primates, carnivora, perissodactyla, artiodactyla and rodentia, for immunohistochemical labeling of the acetylcholine synthesizing enzyme, choline acetyltransferase (ChAT), villin, and taste cascade components (α-gustducin, PLCβ2, TRPM5). Corresponding to findings in previously investigated species, urethral epithelial cells with brush cell shape were immunolabeled in all 11 mammals. In 8 species, immunoreactivities against all marker proteins and ChAT were observed, and double-labeling immunofluorescence confirmed the cholinergic nature of villin-positive and chemosensory (TRPM5-positive) cells. In cat and horse, these cells were not labeled by the ChAT antiserum used in this study, and unspecific reactions of the secondary antiserum precluded conclusions about ChAT-expression in the bovine epithelium. These data indicate that urethral brush cells are widespread throughout the mammalian kingdom and evolved not later than about 64.5millionyears ago.

  19. Idiopathic urethritis in children: Classification and treatment with steroids

    Directory of Open Access Journals (Sweden)

    Sivasankar Jayakumar

    2014-01-01

    Full Text Available Background: Idiopathic urethritis [IU] in children is of unknown etiology and treatment options are limited. We propose a classification for IU based on cystourethroscopy findings and symptoms (Grade 1 - 4 and report our experience with use of topical and oral steroids in IU. Materials and Methods: Retrospective data collection of all male children (0-16 years diagnosed with IU over a period of 8 years between 2005 and 2012 at our institution. Data was collected on patient demographics, laboratory and radiological investigations, cystourethroscopy findings, management and outcomes. Results: A total of 19 male children were diagnosed with IU. The median age of the patients was 13(7-16 years. Presenting symptoms included dysuria in 12; hematuria in 9; loin pain in 6; and scrotal pain in 2 patients. Both patients with scrotal pain had previous left scrotal exploration that revealed epididymitis. Serum C-reactive protein and Full blood count was tested in 15 patients and was within normal limits in all of them. Cystourethroscopy revealed urethritis of grade-I in 2; grade-II in 11; and grade-III in 3 patients. There were 3 patients with systemic symptoms from extra-urethral extension of inflammation (grade-IV. Mean follow up was 18.9(1-74 months. All patients had steroid instillation at the time of cystourethroscopy. Three patients with IU grade IV required oral steroids (prednisolone in view of exacerbation of symptoms and signs despite steroid instillation. Complete resolution of symptoms and signs occurred in 18(94.7% patients. Significant improvement in symptoms and signs was noted in 1(5.3% patient who is still undergoing treatment. Conclusions: IU in male children can be successfully managed with steroid instillation, especially in grade I and II. Grade III, will need steroid instillation but treatment of scarring and stricture will necessitate longer duration of treatment. In children with IU and extra-urethral symptoms (grade IV, oral

  20. [Vesico-urethral lithiasis secondary to foreign body].

    Science.gov (United States)

    Recasens Guinjuan, J R; Flores González, J J; Samsó Piñol, J M; Ribes Amoros, Y; Massó Badia, A

    2002-02-01

    We report a case of vesico-urethral litiasis secondary to foreign body (gauze) calcificated, left in prostatic cell during prostate open surgery of performed twelve years ago. In the related literature we observe that most of foreign urinals bodies are secondary to the introduction through the urethra of objects with autoerotic finality in normal patients or more often with psychiatric disorders, and only a small proportion are of iatrogenic origin, mainly in the last ten years.

  1. [Urethral diverticulum. Our casuistic and the literatura review].

    Science.gov (United States)

    Ramírez Backhaus, M; Trassierra Villa, M; Broseta Rico, E; Gimeno Argente, V; Arlandis Guzmán, S; Alonso Gorrea, M; Jiménez Cruz, J F

    2007-09-01

    The possible etiopathogenic factors, symptoms, diagnostic methods, surgical management and complications of the urethral diverticula are reviewed. A retrospective study of the clinical charts with urethral diverticula diagnosis during the period 1986-2006 was carried out. In the last 20 years a total of 19 patients have been treated for this pathology: 15 females and 4 males. Five of the females started with a sensation of vaginal mass; the rest were diagnosed of micturitional (irritative) syndrome, urinary incontinence or urinary infection. In the case of males, 3 of them had a palpable tumour in the penis. The most used diagnostic method was retrograde and voiding cystourethrography; urethrography with double-occlusion balloon catheter was used in 5 cases and urethroscopy in 4 patients; other techniques of image diagnosis like magnetic resonance imaging were necessary for the most complex cases. The treatment was the excision of the diverticulum, except for one of the females who rejected the treatment. The evolution in all treated women was successful, according to follow up 2 years after the treatment. In males, two of them had complex recurrent diverticula. Urethral diverticula are nosologic entities of difficult diagnosis, due to their low prevalence and their unspecific clinic, therefore diagnosis is sometimes incidental. The etiopathogenity is acquired in most cases and its surgical treatment is more challenging in males than in females probably linked to the fact that diverticula appear in urethras with previous surgery, endourologic manipulation or associated injuries.

  2. Adenocarcinoma uretral em uma cadela Urethral adenocarcinoma in a bitch

    Directory of Open Access Journals (Sweden)

    Marcia Cristina da Silva

    2005-08-01

    Full Text Available Tumores primários de uretra são raros em animais e há poucos relatos em cães. A ocorrência é maior em cadelas idosas, não havendo predileção por raça. Disúria, estrangúria e hematúria são sinais clínicos associados a esses tumores. É relatado um caso de adenocarcinoma primário de uretra em um cadela Poodle de 12 anos de idade que apresentava aumento de volume no membro pélvico esquerdo. Na necropsia, foram encontradas metástases na articulação femorotibial esquerda, na glândula adrenal e no rim.Urethral primary tumors are rare in animals and there are only few reports in dogs. They are more frequent in old bitches and have no breed predilection. Clinical signs associated with urethral primary tumors include dysuria, strangury and hematuria. We report a case of primary urethral adenocarcinoma in a 12-year-old female Poodle that was presented with localized volume enlargement in the left pelvic limb. At necropsy metastasis were found at the left femorotibial joint, adrenal gland and kidney.

  3. Urethral function after cystectomy: a canine in vivo experiment.

    Science.gov (United States)

    Hübner, W A; Trigo-Rocha, F; Plas, E G; Tanagho, E A

    1993-01-01

    To study the function of the pelvic floor and the isolated urethra after removal of the bladder, 5 male and 5 female mongrel dogs were used in an acute in vivo experiment. Urethral pressure changes secondary to unilateral stimulation of the pelvic and pudendal nerves were recorded. After baseline data of the intact system were documented, the following procedures were carried out: separation of the urethra from the bladder neck (prostate), nerve-sparing cystectomy (cystoprostatectomy), and cold-knife incision through the entire length of the proximal urethra. Pressure recordings were repeated after each step of surgery. Pudendal nerve stimulation resulted in rapid and large pressure rises in the distal urethra (reaction typical of striated muscle). This response remained unchanged after all three surgical steps. Pelvic nerve stimulation provoked pressure rises within the urethra of a pattern typical of smooth muscle. The findings persisted after separation of the urethra from the bladder neck (prostate) and after cystectomy, but were not observed after urethrotomy. Contractions secondary to pudendal nerve stimulation were inhibited by curare, which did not affect the reaction to pelvic nerve stimulation. Our experiments demonstrate that in the dog the continuity of bladder and urethra is not required for the function of urethral closure mechanisms. The contractile potency of the urethral smooth muscles remains intact after nerve-sparing cystectomy. We believe that problems with the baseline continence of surrogate bladders should mainly be ascribed to a lack of surgical caution in preserving the autonomic nerves of cystectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Somatomotor and sensory urethral control of micturition in female rats

    Science.gov (United States)

    Cruz, Yolanda; Pastelín, César; Balog, Brian M.; Zaszczurynski, Paul J.

    2014-01-01

    In rats, axons of external urethral sphincter (EUS) motoneurons travel through the anastomotic branch of the pudendal nerve (ABPD) and anastomotic branch of the lumbosacral trunk (ABLT) and converge in the motor branch of the sacral plexus (MBSP). The aim of the present study was to determine in female rats the contribution of these somatomotor pathways and urethral sensory innervation from the dorsal nerve of the clitoris on urinary continence and voiding. EUS electromyographic (EMG) activity during cystometry, leak point pressure (LPP), and voiding efficiency (VE) were assessed in anesthetized virgin Sprague-Dawley female rats before and after transection of the above nerve branches. Transection of the MBSP eliminated EUS EMG, decreased LPP by 50%, and significantly reduced bladder contraction duration, peak pressure, intercontraction interval, and VE. Transection of the ABPD or ABLT decreased EUS EMG discharge and LPP by 25% but did not affect VE. Transection of the dorsal nerve of the clitoris did not affect LPP but reduced contraction duration, peak pressure, intercontraction interval, and VE. We conclude that somatomotor control of micturition is provided by the MBSP with axons travelling through the ABPD and ABLT. Partial somatomotor urethral denervation induces mild urinary incontinence, whereas partial afferent denervation induces voiding dysfunction. ABPD and ABLT pathways could represent a safeguard ensuring innervation to the EUS in case of upper nerve damage. Detailed knowledge of neuroanatomy and functional innervation of the urethra will enable more accurate animal models of neural development, disease, and dysfunction in the future. PMID:25339694

  5. Ruptured urinary bladder attributable to urethral compression by a haematoma after vertebral fracture in a bull

    OpenAIRE

    Braun, U.; Trösch, L; Sydler, T.

    2014-01-01

    BACKGROUND: In male cattle, rupture of the urinary bladder is usually associated with urethral obstruction by uroliths. Less common causes include urethral compression or stricture. This case report describes the findings in a young Limousion breeding bull with rupture of the urinary bladder because of urethral compression by a haematoma after coccygeal fracture. CASE PRESENTATION: The bull had been introduced into a 40-head Red-Holstein herd one week before being injured. One week after intr...

  6. Relationship of nutritional factors to the cause, dissolution, and prevention of feline uroliths and urethral plugs.

    Science.gov (United States)

    Osborne, C A; Polzin, D J; Kruger, J M; Lulich, J P; Johnston, G R; O'Brien, T D

    1989-05-01

    Feline lower urinary tract disease is often associated with uroliths and urethral plugs. Uroliths and urethral plugs are composed of variable quantities of matrix and a variety of minerals (including struvite, calcium oxalate, ammonium urate, calcium phosphate, and cystine). Knowledge of nutritional factors associated with the pathophysiology of uroliths and urethral plugs facilitates the modification of diets for the dissolution of several minerals contained within them.

  7. Management of male urethral polyps in children: Experience with four cases

    Directory of Open Access Journals (Sweden)

    Eziyi Amogu

    2009-01-01

    Full Text Available Congenital urethral polyps area rare anomaly of the male urethra that may present with features of voiding dysfunction or obstruction. Although the exact incidence is unknown, they are important in the differential diagnosis of lower urethral obstruction in male children. Their diagnosis requires a high index of suspicion because of the variability of presentation. We present our experience with four cases of male urethral polyps in boys with discussion on the related literature.

  8. Female urethral diverticulum presenting with acute urinary retention: Reporting the largest diverticulum with review of literature

    Directory of Open Access Journals (Sweden)

    Manas Ranjan Pradhan

    2012-01-01

    Full Text Available Female urethral diverticulum is a rare entity with diverse spectrum of clinical manifestations. It is a very rare cause of bladder outlet obstruction and should be considered as a differential diagnosis in females presenting with acute urinary retention associated with a vaginal mass. Strong clinical suspicion combined with thorough physical examination and focused radiological investigations are vital for its diagnosis. Herein we report a case of giant urethral diverticulum presenting with acute urinary retention in a young female. It was managed by excision and urethral closure, and is the largest urethral diverticulum reported till date in the literature.

  9. Effect of fesoterodine on urethral closure function in women with stress urinary incontinence assessed by urethral pressure reflectometry.

    Science.gov (United States)

    Klarskov, Niels; Darekar, Amanda; Scholfield, David; Whelan, Laurence; Lose, Gunnar

    2014-06-01

    The aim was to evaluate, using urethral pressure reflectometry (UPR), the effect of fesoterodine on urethral function in women with stress urinary incontinence (SUI). Women aged 18 to 65 years were eligible for this randomised, double-blind, placebo-controlled, crossover study if they had had clinically significant SUI or SUI-predominant mixed urinary incontinence for >3 months. Each participant received fesoterodine 4 mg, fesoterodine 8 mg, and placebo once daily for 7 days, with a 7- to 10-day washout between treatments. UPR was performed at baseline and 4 to 8 h after the last dose in each treatment period. Participants completed a 3-day bladder diary before randomisation and during the last 3 days of each treatment period. Of the 22 women randomly assigned and treated, 17 met the criteria for the primary efficacy analyses. No statistically significant differences were seen between fesoterodine 4 mg or fesoterodine 8 mg and placebo in opening urethral pressure (primary endpoint) or other UPR endpoints. No statistically significant differences were seen between either fesoterodine dose and placebo in the change from baseline in the bladder diary variables (total urinary incontinence, SUI, or urgency urinary incontinence episodes per 24 h). Adverse events were reported by 8 participants taking fesoterodine 4 mg, 17 taking fesoterodine 8 mg, and 8 taking placebo. Fesoterodine did not affect urethral pressure or significantly decrease the number of incontinence episodes in women with SUI. The UPR parameters showed no placebo effect, while there was a placebo effect of 60 % based on the bladder diary.

  10. Present and future of endovascular SFA treatment: stents, stent-grafts, drug coated balloons and drug coated stents.

    Science.gov (United States)

    Bosiers, M; Deloose, K; Verbist, J; Peeters, P

    2008-04-01

    The current evolution towards treating more complex femoropopliteal lesions as seen in the renewed TASC II recommendations clearly reflects the continuous evolutions in femoropopliteal stent design. Recent stent design improvements focus on decreasing stent fractures rates which can negatively impact patency rates. By rearranging strut alignment towards helical connecting bridges or full helical stent designs, stent designers have successfully improved the fracture resistance of their stents. The superior fracture resistance of the latest stent generation in combination with the production of long nitinol stents of up to 20 cm in length allow that more difficult and complex lesions can be treated endovascularly. The continuous perfection of nitinol stent platforms followed by the transfer of coronary technologies (e.g. active coatings) towards peripheral devices might broaden the indications for the minimal invasive strategy towards TransAtlantic Inter-Society Consensus (TASC) II C&D lesions.

  11. Clinical outcomes of self-expandable stent placementfor benign esophageal diseases: A pooled analysis of theliterature

    Institute of Scientific and Technical Information of China (English)

    Emo E van Halsema; Jeanin E van Hooft

    2015-01-01

    AIM: To analyze the outcomes of self-expandable stentplacement for benign esophageal strictures and benignesophageal leaks in the literature.METHODS: The PubMed, Embase and Cochranedatabases were searched for relevant articles publishedbetween January 2000 and July 2014. Eight prospectivestudies were identified that analyzed the outcomesof stent placement for refractory benign esophagealstrictures. The outcomes of stent placement forbenign esophageal leaks, perforations and fistulaewere extracted from 20 retrospective studies thatwere published after the inclusion period of a recentsystematic review. Data were pooled and analyzedusing descriptive statistics.RESULTS: Fully covered self-expandable metal stents(FC SEMS) (n = 85), biodegradable (BD) stents (n =77) and self-expandable plastic stents (SEPS) (n = 70)were inserted in 232 patients with refractory benignesophageal strictures. The overall clinical success ratewas 24.2% and according to stent type 14.1% forFC SEMS, 32.9% for BD stents and 27.1% for SEPS.Stent migration occurred in 24.6% of cases. Theoverall complication rate was 31.0%, including major(17.7%) and minor (13.4%) complications. A total of643 patients were treated with self-expandable stentsmainly for postsurgical leaks (64.5%), iatrogenicperforations (19.6%), Boerhaave's syndrome (7.8%)and fistulae (3.7%). FC SEMS and partially coveredSEMS were used in the majority of patients. Successfulclosure of the defect was achieved in 76.8% ofpatients and according to etiology in 81.4% forpostsurgical leaks, 86.0% for perforations and 64.7%for fistulae. The pooled stent migration rate was16.5%. Stent-related complications occurred in 13.4%of patients, including major (7.8%) and minor (5.5%)complications.CONCLUSION: The outcomes of stent placementfor refractory benign esophageal strictures were poor.However, randomized trials are needed to put thisinto perspective. The evidence on successful

  12. Biodegradable fiksasyon malzemeleri

    OpenAIRE

    Seber, Sinan

    2004-01-01

    Problems related to metallic implant had increased the interest to biodegradables. In this paper, the physical and chemical properties, degradation modalities, implant design, clinical studies with techniques, and complications of biodegradable implants, especially polylactic and polyglycolic acid, were reviewed. Also our studies, on the antibiotic delivery capacities of these implants; and the prediction of immunological reactions with our clinical experiences were presented.

  13. Biodegradation of plastics.

    Science.gov (United States)

    Shimao, M

    2001-06-01

    Widespread studies on the biodegradation of plastics have been carried out in order to overcome the environmental problems associated with synthetic plastic waste. Recent work has included studies of the distribution of synthetic polymer-degrading microorganisms in the environment, the isolation of new microorganisms for biodegradation, the discovery of new degradation enzymes, and the cloning of genes for synthetic polymer-degrading enzymes.

  14. DJ stent - boon or curse?

    Directory of Open Access Journals (Sweden)

    AS Agrawal

    2014-04-01

    Full Text Available DJ stent is considered as a boon by the urologist but without proper knowledge it turns to be curse for the patient. We report a case of a 34 year old man who developed vesical calculus secondary to DJ stent in a short span of 6-8 months. He underwent cystolithotomy for removal of the vesical calculus along with the DJ stent. Journal of College of Medical Sciences-Nepal, 2013, Vol-9, No-3, 55-59 DOI: http://dx.doi.org/10.3126/jcmsn.v9i3.10224  

  15. Evaluating Stent Optimisation Technique (StentBoost®) in a Dedicated Bifurcation Stent (the Tryton™)

    Energy Technology Data Exchange (ETDEWEB)

    Fysal, Zamil; Hyde, Thomas; Barnes, Edward; McCrea, William; Ramcharitar, Steve, E-mail: steve.ramcharitar@chem.ox.ac.uk

    2014-03-15

    Background/Purpose: To evaluate the use of StentBoost® in the Tryton™ dedicated SideBranch Stent. Methods and Results: The Tryton™ SideBranch Stent has been effectively used to manage complex bifurcations. However, the paucity of scaffolding in the proximal part of the stent makes it often difficult to visualise under standard radiographic imaging. We set out to evaluate whether by using an augmented radiographic imaging technique it was possible to aid visualisation of the stent. In particular the so call 'wedding ring' band which is crucial to the procedural success. We further evaluated whether it was possible to determine the apposition of the stent at the carina, its coverage and the ability to aid recrossing of the struts closest to the carina as well as the added radiation exposure. Conclusions: StentBoost® was found to be invaluable to the procedural success of the Tryton™ deployment without adding any extra cost to the procedure and with only a 3.7% increase in radiation to the patient. It allowed enhanced visualisation in all cases to aid apposition, recrossing and coverage.

  16. Next generation drug-eluting stents: focus on bioabsorbable platforms and polymers

    Directory of Open Access Journals (Sweden)

    Brendan Doyle

    2009-11-01

    Full Text Available Brendan Doyle, David R Holmes JrDivision of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USAAbstract: The success of drug-eluting stents in preventing restenosis has shifted the focus of new stent development toward enhancing long term safety and efficacy of these devices, while simultaneously eliminating the need for indefinite dual antiplatelet therapy. A technical advance fulfilling these aims would hold tremendous potential to reduce morbidity, mortality and economic costs associated with the percutaneous treatment of coronary artery disease. An attractive approach is the use of bioabsorbable stent designs. These may include stents with different bioabsorbable drugs, bioabsorbable polymers or even bioabsorbable metallic backbones. A device that could achieve excellent acute and long-term results, but disappear completely within months (thereby avoiding the need for prolonged dual antiplatelet therapy, would be a tremendous advance. Too good to be true? We explore here the scientific rationale and prospects for success with this exciting concept.Keywords: percutaneous coronary intervention, biodegradable, bioabsorbable, polymer, stent

  17. A simplified in vivo approach for evaluating the bioabsorbable behavior of candidate stent materials.

    Science.gov (United States)

    Pierson, Daniel; Edick, Jacob; Tauscher, Aaron; Pokorney, Ellen; Bowen, Patrick; Gelbaugh, Jesse; Stinson, Jon; Getty, Heather; Lee, Chee Huei; Drelich, Jaroslaw; Goldman, Jeremy

    2012-01-01

    Metal stents are commonly used to revascularize occluded arteries. A bioabsorbable metal stent that harmlessly erodes away over time may minimize the normal chronic risks associated with permanent implants. However, there is no simple, low-cost method of introducing candidate materials into the arterial environment. Here, we developed a novel experimental model where a biomaterial wire is implanted into a rat artery lumen (simulating bioabsorbable stent blood contact) or artery wall (simulating bioabsorbable stent matrix contact). We use this model to clarify the corrosion mechanism of iron (≥99.5 wt %), which is a candidate bioabsorbable stent material due to its biocompatibility and mechanical strength. We found that iron wire encapsulation within the arterial wall extracellular matrix resulted in substantial biocorrosion by 22 days, with a voluminous corrosion product retained within the vessel wall at 9 months. In contrast, the blood-contacting luminal implant experienced minimal biocorrosion at 9 months. The importance of arterial blood versus arterial wall contact for regulating biocorrosion was confirmed with magnesium wires. We found that magnesium was highly corroded when placed in the arterial wall but was not corroded when exposed to blood in the arterial lumen for 3 weeks. The results demonstrate the capability of the vascular implantation model to conduct rapid in vivo assessments of vascular biomaterial corrosion behavior and to predict long-term biocorrosion behavior from material analyses. The results also highlight the critical role of the arterial environment (blood vs. matrix contact) in directing the corrosion behavior of biodegradable metals.

  18. Investigation of long-term implantation of BuMA stent in a porcine coronary model

    Institute of Scientific and Technical Information of China (English)

    CHEN Ming; WANG Xin-gang; ZHENG Bo; PENG Hong-yu; Zhang Xiao-yan; ZHANG Bin; HUO Yong

    2012-01-01

    Background Stent-based delivery of sirolimus has been shown to reduce neointimal hyperplasia significantly.However,the long-term effect of the polymer is thought to initiate and sustain an inflammatory response and contribute to the occurrence of late complications.Our study aimed to evaluate the efficacy and safety of the BuMA biodegradable drug-coated sirolimus-eluting stent(BSES)for inhibiting neointimal hyperplasia in a porcine coronary model.Methods Four types of stents were implanted at random in different coronary arteries of the same pig:BSES(n=24),bare metal stent(BMS)(n=24),biodegradable polymer coated stent without drug(PCS)(n=24)and only poly(n-butyl methacrylate)base layer coated stent(EGS)(n=23).In total,26 animals underwent successful random placement of 95 oversized stents in the coronary arteries.Coronary angiography was performed after 28 days,90 days and 240 days of stent implantation.After 14 days,28 days,90 days and 240 days,6 animals at each timepoint were sacrificed for histomorphologic analysis.Results The 28-day,90-day and 240-day results of quantitative coronary angiography(QCA)showed reduction in luminal loss(LL)in the BSES group when compared with the BMS group;(0.20±0.35)mm vs.(0.82±0.51)mm(P=0.035),(0.20±0.30)mm vs.(0.93±0.51)mm(P=0.013),and(0.18±0.16)mm vs.(0.19±0.24)mm(P=0.889),respectively.By 28-day,90-day and 240-day histomorphomeric analysis results,there was also a corresponding significant reduction in neointimal tissue proliferation with similar injury scores of BSES compared with the BMS control;average neointimal area(0.90±0.49)mm2 vs.(2.16±1.29)mm2(P=0.049),(1.53±0.84)mm2 vs.(3.41±1.55)mm2(P=0.026),and(2.43±0.95)mm2 vs.(3.12±1.16)mm2(P=0.228),respectively.High magnification histomorphologic examination revealed similar inflammation scores and endothelialization scores in both the BSES and BMS groups.Conclusions The BuMA biodegradable drug-coated sirolimus-eluting stents can significantly reduce neointimal

  19. Management Of Encrusted Ureteral stents

    African Journals Online (AJOL)

    imac-3

    Objectives: To present our experience in managing encrusted ureteral stents and to review the .... A single anesthetic session was required in 18 patients (81.8%) and ... fluid intake, chemotherapy-induced hyperuricosuria, persistent or.

  20. Novel side branch ostial stent.

    Science.gov (United States)

    Chen, Shao-Liang; Lv, Shu-Zheng; Kwan, Tak W

    2009-04-01

    Bifurcation lesions are technically challenging and plagued by a high incidence of restenosis, especially at the side branch orifice, which results in a more frequent need for revascularization during the follow-up period. This report discusses two clinical experiences with a novel side branch ostial stent, the BIGUARD stent, designed for the treatment of bifurcation lesions; procedural success with no in-hospital complications was observed in types IVb and Ia lesions.

  1. Tissue Engineering for Human Urethral Reconstruction : Systematic Review of Recent Literature

    NARCIS (Netherlands)

    de Kemp, Vincent; de Graaf, Petra; Fledderus, Joost O.; Bosch, JLHR; de Kort, Laetitia

    2015-01-01

    Background Techniques to treat urethral stricture and hypospadias are restricted, as substitution of the unhealthy urethra with tissue from other origins (skin, bladder or buccal mucosa) has some limitations. Therefore, alternative sources of tissue for use in urethral reconstructions are considered

  2. A Rare Cause of Recurrent Urinary Tract Infections, Female Urethral Diverticulum: A Case Report

    Directory of Open Access Journals (Sweden)

    Taha Numan Yikilmaz

    2014-02-01

    Full Text Available A female urethral diverticulum is an uncommon pathologic entity. The most presentation of urethral diverticule has been described as lower urinary tract symptoms and dyspareunia. The case of female is presented, who consult with a vaginal mass and dyspareunia and current literature was reviewed.

  3. Urethral sensory threshold and urethro-anal reflex latency in continent women.

    Science.gov (United States)

    Cavalcanti, Geraldo de Aguiar; Bruschini, Homero; Manzano, Gilberto M; Giuliano, Lydia P; Nóbrega, João Antônio M; Srougi, Miguel

    2007-01-01

    The sensory evaluation of the lower urinary tract is summarized in the bladder proprioceptive sensitivity during cystometry. Experimental studies suggest that abnormalities of the urethral innervation and micturition reflex can be related to the presence of continence disturbances. This study aimed to measure the urethral sensory threshold and the urethro-anal reflex latency in healthy volunteers, establishing reading criteria, comparing the results and technique used with the literature and verifying the effect of physiological factors. Thirty healthy female volunteers were studied. They had an absence of genital or urinary complaints and had undergone no previous pelvic or vaginal procedures. The measurement of the urethral sensory threshold and urethro-anal reflex latency were performed as described. The determination of the urethral sensory threshold and urethro-anal reflex latency were obtained in 96.6% of the volunteers. The electrophysiological parameters did not correlate with age, parity or number of vaginal deliveries. There was a positive association of the urethral sensory threshold with height. Technical aspects were considered and compared with those in the literature as well as the advantages and limitations of the method. The measurement of the urethral sensory threshold and urethro-anal reflex latency presented consistent recordings. The urethral sensory threshold should be analyzed carefully in individuals with height above the population average. Subsequent observations are necessary to clarify their function in patients with continence disturbances and to measure the urethral function, but these values can be used as normal parameters for comparison.

  4. Outcomes of urethral calculi patients in an endemic region and an undiagnosed primary fossa navicularis calculus.

    Science.gov (United States)

    Verit, Ayhan; Savas, Murat; Ciftci, Halil; Unal, Dogan; Yeni, Ercan; Kaya, Mete

    2006-02-01

    Urethral calculus is a rare form of urolithiasis with an incidence lower than 0.3%. We determined the outcomes of 15 patients with urethral stone, of which 8 were pediatric, including an undiagnosed primary fossa navicularis calculus. Fifteen consecutive male patients, of whom eight were children, with urethral calculi were assessed between 2000 and 2005 with a mean of 19 months' follow-up. All stones were fusiform in shape and solitary. Acute urinary retention, interrupted or weak stream, pain (penile, urethral, perineal) and gross hematuria were the main presenting symptoms in 7 (46.7%), 4 (26.7%), 3 (20%) and 1 (6.6%) patient, respectively. Six of them had accompanying urethral pathologies such as stenosis (primary or with hypospadias) and diverticulum. Two patients were associated with upper urinary tract calculi but none of them secondary to bladder calculi. A 50-year-old patient with a primary urethral stone disease had urethral meatal stenosis accompanied by lifelong lower urinary tract symptoms. Unlike the past reports, urethral stones secondary to bladder calculi were decreasing, especially in the pediatric population. However, the pediatric patients in their first decade are still under risk secondary to the upper urinary tract calculi or the primary ones.

  5. A faster urethral pressure reflectometry technique for evaluating the squeezing function

    DEFF Research Database (Denmark)

    Klarskov, Niels; Saaby, Marie-Louise; Lose, Gunnar

    2013-01-01

    Abstract Objective. Urethral pressure reflectometry (UPR) has shown to be superior in evaluating the squeeze function compared to urethral pressure profilometry. The conventional UPR measurement (step method) required up to 15 squeezes to provide one measure of the squeezing opening pressure and ...

  6. The impact of tension-free vaginal tape on the urethral closure function

    DEFF Research Database (Denmark)

    Saaby, Marie-Louise; Klarskov, Niels; Lose, Gunnar

    2015-01-01

    AIM: To investigate if the tension-free vaginal tape (TVT) works by increasing the abdominal to urethral pressure impact ratio (APIR). METHODS: Twenty one women with urodynamically proven stress urinary incontinence (SUI) were assessed by ICIQ-SF, pad-weighing test, incontinence diary and Urethral...

  7. Persistent Urethritis and Prostatitis Due to Trichomonas vaginalis: A Case Report

    Directory of Open Access Journals (Sweden)

    Alireza Abdolrasouli

    2007-01-01

    Full Text Available The present report describes a case of persistent urethritis accompanied by prostatitis due to Trichomonas vaginalis in a young male patient. The importance of the laboratory diagnosis of trichomoniasis in persistent or recurrent urethritis (ie, testing samples from multiple sites is highlighted, with the aim of improving the clinical recognition of this pathogen.

  8. Congenital urethral polyps: a report of two cases; Polipos uretrales congenitos. A proposito de dos casos

    Energy Technology Data Exchange (ETDEWEB)

    Cano, D.; Vivas, I.; Torres, E.; Garcia, L.; Fernandez-Villa, T. [Clinica Universitaria de Navarra. Pamplona (Spain)

    1999-07-01

    Congenital urethral polyps are uncommon lesions, very few cases of which have been previously reported in the literature. We present two cases of congenital urethral polyps in children, describing the clinical and radiological features and the diagnostic method employed, as well as reviewing the literature. (Author) 6 refs.

  9. Case of a congenital urethral duplication being unmasked following circumcision for balanitis xerotica obliterans.

    Science.gov (United States)

    Boyd, Matthew; Woodward, Mark; Lambert, Anthony

    2010-07-01

    We present the case of an 11-year-old boy diagnosed with an Effmann Type II A1 urethral duplication after routine circumcision for balanitis xerotica obliterans (BXO). We discuss the pathophysiology, investigation and management both of BXO and urethral duplication.

  10. Inappropriateness in biliary stenting

    Directory of Open Access Journals (Sweden)

    Giuseppe Chesi

    2013-10-01

    Full Text Available Starting from a real case of a 69-year old patient affected by cholangiocarcinoma, we intend to discuss the accuracy and appropriateness of the diagnostic and therapeutic procedures adopted. This case shows in particular that a more accurate preoperative staging could probably avoid the patient unnecessary laparotomy. According to the indications in the medical literature, this patient could possibly benefit from chemotherapy, but a chemoembolization of liver metastases was performed. However in the literature no available evidence suggests that this treatment would be beneficial in this kind of clinical picture. Eventually, when the disease was already at an advanced stage and worsened due to a necrosis of the left hepatic lobe and a cholangitic infection, a repositioning of the stent on the stent was performed, despite in the literature the life expectancy cut-off for this procedure is at least 6 months. We also discuss the communication between the physician, the patient and the family, which was probably based on overly optimistic and unrealistic expectations. This led to a number of surgical procedures, which were not certainly helpful and indeed were probably even harmful for this patient. In addition, these procedures caused unnecessary costs borne by the healthcare system. In conclusion, we advocate that discussion and self-assessment must be always promoted, so that the healthcare professionals can review the process and the outcome of their treatment as well as their behavior to understand if it could have been more appropriate to offer actual benefits to the patients in terms of better quality of life and longer life expectancy.

  11. Forgotten Ureteral Stents: An Avoidable Morbidity.

    Science.gov (United States)

    Murtaza, Badar; Alvi, Sarwar

    2016-03-01

    To assess the clinical presentation of forgotten ureteral stents and highlight the etiological factors resulting in the retention of these stents. Observational study. Department of Urology, Armed Forces Institute of Urology, Rawalpindi, from January 2010 to June 2011. Thirty-eight patients, with forgotten ureteral stents, retained for more than 6 months duration, were enrolled. A detailed evaluation was performed, along with the questions regarding the patients' opinion about the ureteral stents. They were specially asked whether they knew about the stents or were they formally informed regarding the stents. Subsequently, the patients were managed according to their clinical condition. The male to female ratio was 2.1:1 aged 23 - 69 years, mean being 40.24 ±12.59 years. The time of presentation after the ureteral stenting was 7 - 180 months (mean = 28.89 ±33.435 years). Seven patients (18.4%) reported with chronic kidney disease, including ESRD in two cases. Recurrent UTI was seen in 28 cases (73.6%), calculus formed over the stents in 20 cases (52.6%), and stent fragmented in 5 patients (13.1%). Majority of patients, (n = 23, 60.5%), were not even aware of the placement of these stents while 8 (21.0%) knew but were reluctant about its removal. In 3 cases (7.8%), the relatives knew about the stent but never informed the patients. The stent had been removed in 2 cases (5.2%), but the other broken fragment was missed. One case (2.6%) each had a misconception about the permanent placement of the stents like cardiac stents and regarding degradation of the stents in situ. Forgotten ureteral stents produce clinical features ranging from recurrent UTI to ESRD. This preventable urological complication is primarily due to the unawareness or ignorance of the patients and their relatives regarding the stent.

  12. Erectile function after anastomotic urethroplasty for pelvic fracture urethral injuries.

    Science.gov (United States)

    El-Assmy, A; Harraz, A M; Benhassan, M; Nabeeh, A; Ibrahiem, El Hi

    2016-07-01

    There is an established association between ED and pelvic fracture urethral injuries (PFUIs). However, ED can occur after the injury and/or the urethral repair. To our knowledge, only one study of erectile function (EF) after urethroplasty for PFUIs used a validated questionnaire. This study was carried out to determine the impact of anastomotic posterior urethroplasty for PFUIs on EF. We retrospectively reviewed the computerized surgical records to identify patients who underwent anastomotic urethroplasty for PFUIs from 1998 to 2014. Those patients were contacted by phone or mail and were re-evaluated in the outpatient clinic by International Index of Erectile Function questionnaire; in unmarried men, the single-question self-report of ED was used for evaluation of EF, clinical examination and penile color Doppler ultrasonography (CDU) for men with ED. Overall, 58 patients were included in the study among whom 36 (62%) men were sexually active and the remaining 22 (38%) were single. The incidence of ED among our group is 72%. All patients developed ED after initial pelvic trauma and none of our patients had impaired EF after urethroplasty. The incidence of ED increased proportionally with severity of pelvic trauma. All patients with type-C pelvic fracture, associated symphysis pubis diastasis, sacroiliac joints diastasis and bilateral pubic ramus fractures had ED. Men with PFUIs had worse EF than men in other series with pelvic fractures without urethral injury. The majority (88%) of men with ED showed veno-occlusive dysfunction on penile CDU. So we concluded that men with PFUIs had a high incidence of ED up to 72%. Anastomotic posterior urethroplasty had no negative impact on EF and the development of ED after PFUIs was related to the severity of the original pelvic trauma. Veno-occlusive dysfunction is the commonest etiology of ED on penile CDU.

  13. Coronary aneurysm and very late stent thrombosis formation associated with sirolimus-eluting stent implantation

    Institute of Scientific and Technical Information of China (English)

    XIE Hong-zhi; ZHANG Shu-yang; ZENG Yong; SHEN Zhu-jun; FANG Quan

    2009-01-01

    @@ Since drug-eluting stents (DES) can significantly reduce the risk of instant restenosis compared with bare-metal stents, they have been widely used in interventional therapy for coronary heart disease. With bare-metal stents being rapidly replaced by DES there is a great concern about the safety of DES due to stent thrombosis.~(1,2)

  14. Válvula de uretra anterior Anterior urethral valves

    Directory of Open Access Journals (Sweden)

    Silvio Tucci Jr.

    2003-02-01

    Full Text Available Objetivo: apresentar os aspectos clínicos, diagnósticos e terapêuticos de pacientes portadores de válvula da uretra anterior. Descrição: em dois neonatos, o diagnóstico presuntivo de patologia obstrutiva do trato urinário foi sugerido pela ultra-sonografia realizada no período pré-natal, confirmando-se o diagnóstico de válvula de uretra anterior pela avaliação pós-natal. Os pacientes foram submetidos a tratamento cirúrgico paliativo, com vesicostomia temporária e, posteriormente, definitivo, pela fulguração endoscópica das válvulas. Ambos evoluíram com função renal normal. Comentários: a válvula da uretra anterior é anomalia rara que deve ser considerada em meninos com quadro radiológico pré-natal sugestivo de obstrução infravesical, secundariamente à hipótese mais comum de válvula da uretra posterior. Ressaltamos a utilização da vesicostomia como derivação urinária temporária nestes casos, prevenindo potenciais complicações pela manipulação da uretra do recém-nascido.Objective: to discuss clinical signs, diagnostic tools and therapeutics of anterior urethral valves, an obstructive anomaly of the urinary system in males. Description: signs of urinary tract obstruction were identified on pre-natal ultrasound in two male fetuses and the diagnosis of anterior urethral valves was made through post-natal evaluation. As an initial treatment, vesicostomy was performed in both patients. Later, the valves were fulgurated using an endoscopic procedure. During the follow-up period both patients presented normal renal function. Comments: anterior urethral valves are a rare form of urethral anomaly that must be ruled out in boys with pre-natal ultrasound indicating infravesical obstruction. Vesicostomy used as an initial treatment rather than transurethral fulguration may prevent potential complications that can occur due to the small size of the neonatal urethra.

  15. Urethral duplication with unusual cause of bladder outlet obstruction

    Directory of Open Access Journals (Sweden)

    Vivek Venkatramani

    2016-01-01

    Full Text Available A 12-year-old boy presented with poor flow and recurrent urinary tract infections following hypospadias repair at the age of 3 years. The evaluation revealed urethral duplication with a hypoplastic dorsal urethra and patent ventral urethra. He also had duplication of the bladder neck, and on voiding cystourethrogram the ventral bladder neck appeared hypoplastic and compressed by the dorsal bladder neck during voiding. The possibility of functional obstruction of the ventral urethra by the occluded dorsal urethra was suspected, and he underwent a successful urethro-urethrostomy.

  16. Retained Urethral Catheter Secondary to Placement in Proximal Ureter

    Directory of Open Access Journals (Sweden)

    Thomas B. McGregor

    2016-01-01

    Full Text Available We present an unusual complication secondary to indwelling urethral catheter placement. Routine catheter placement by the obstetrics team in a postpartum female leads to retention of the catheter and inability of its removal by both the obstetrics and urology teams. Although a retained urinary catheter is relatively common, inability to remove a catheter secondary to placement inadvertently into a ureter is extremely rare. In this paper we will discuss the options in removing a retained catheter and present our case of a retained catheter secondary to placement within the right proximal ureter.

  17. Retained Urethral Catheter Secondary to Placement in Proximal Ureter.

    Science.gov (United States)

    McGregor, Thomas B; Sharda, Rajan

    2016-01-01

    We present an unusual complication secondary to indwelling urethral catheter placement. Routine catheter placement by the obstetrics team in a postpartum female leads to retention of the catheter and inability of its removal by both the obstetrics and urology teams. Although a retained urinary catheter is relatively common, inability to remove a catheter secondary to placement inadvertently into a ureter is extremely rare. In this paper we will discuss the options in removing a retained catheter and present our case of a retained catheter secondary to placement within the right proximal ureter.

  18. Medical management of urethral and colonic perforation associated with urinary catheterization in a kitten.

    Science.gov (United States)

    Whittemore, Jacqueline C; Zucca, Lynda

    2003-09-15

    A 6-week-old male kitten was evaluated because of stranguria and possible urethral blockage; a urinary catheter placed during general anesthesia penetrated the urethral and colonic walls and entered the colon. Treatment was conservative, with fluids administered i.v., administration of piperacillin, and supportive care. The kitten never became febrile or clinically ill and continued to thrive. There was no development of clinical signs consistent with stricture, diverticulum, or fistula formation. Complications from urethral perforation include infection and urethral stricture. Reconstructive surgery is considered the treatment of choice for traumatic urethral-colonic perforation. However, surgery may not be feasible or may be cost-prohibitive in certain situations. In such instances, medical management may provide a reasonable alternative to euthanasia.

  19. Very late coronary aneurysm formation with subsequent stent thrombosis secondary to drug-eluting stent

    Institute of Scientific and Technical Information of China (English)

    Ibrahim Akin,; Stephan Kische; Tim C Rehders; Henrik Schneider; G(o)kmen R Turan; Tilo Kleinfeldt; Jasmin Ortak; Christoph A. Nienaber; Hüseyin Ince

    2011-01-01

    Drug-eluting stents have changed the practice in interventional cardiology.With the widespread use of these stents important safety concerns regarding stent thrombosis and formation of coronary artery aneurysm have been expressed.While the majority of attention was focused on stent thrombosis,the formation of coronary aneurysm was only described in anecdotal reports.We report on a patient who suffered from very late stent thrombosis in association with coronary artery aneurysm formation secondary to drug-eluting stent but not to bare-metal stent.

  20. Mechanisms of Biliary Plastic Stent Occlusion and Efforts at Prevention

    Science.gov (United States)

    Kwon, Chang-Il; Lehman, Glen A.

    2016-01-01

    Biliary stenting via endoscopic retrograde cholangiopancreatography has greatly improved the quality of patient care over the last 30 years. Plastic stent occlusion limits the life span of such stents. Attempts to improve plastic stent patency duration have mostly failed. Metal stents (self-expandable metal stents [SEMSs]) have therefore replaced plastic stents, especially for malignant biliary strictures. SEMS are at least 10 times more expensive than plastic stents. In this focused review, we will discuss basic mechanisms of plastic stent occlusion, along with a systematic summary of previous efforts and related studies to improve stent patency and potential new techniques to overcome existing limitations. PMID:27000422

  1. Preventive role of palladium-103 radioactive stent on in-stent restenosis in rabbit iliac arteries

    Institute of Scientific and Technical Information of China (English)

    LUO Quan-Yong; CHEN Li-Bo; YUAN Zhi-Bin; LU Han-Kui; ZHU Rui-Sen

    2005-01-01

    The abilility of γ-emitting palladium-103 stent implantation to inhibit in-stent restenosis in rabbit iliac arteries was investigated. Quantitative histomorphometry of the stented iliac segments 28 days after the implantation indicated that palladium-103 stents made a significant reduction in neointimal area and percent area stenosis compared with the nonradioactive stents. Lumen area in the palladium-103 stents treatment group was larger than the control group. However, the reduction of neointima formation by palladium-103 stents implantation was in a non-dose-dependent fashion. Low ionizing radiation doses via γ-emitting palladiurn-103 stent are effective in preventing neointimal hyperplasia in iliac arteries of rabbits. Palladium-103 stents can be employed as a possible novel means to prevent in-stent restenosis.

  2. The Potential of Magnesium Alloys as Bioabsorbable/ Biodegradable Implants for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    F. Živić

    2014-03-01

    Full Text Available The potential of magnesium alloys as bioabsorbable / biodegradable implants for biomedical applications has been extensively studied as emerging direction. This paper gives a review of current topics in this field. Research activities related to biomedical magnesium alloys have been pursued in two main directions, orthopedic and cardiovascular implants, by investigating different aspects of alloying system design, novel structures, degradation rate control, and surface modification methods. Magnesium alloys are currently considered for applications as load-bearing implant devices such as plates, screws and pins for repairing bone fracture. Highly important direction of research is degradable coronary stents. Degradable vessel stents promote stable vessel regeneration, unlike permanent stents. Different combinations of alloying elements have been investigated in order to decrease corrosion rate.Tribological issues are also important for understanding of different phenomenon related to prolongation of Mg alloys corrosion degradation time/rate, such as tribocorrosion, corrosion fatigue, and fatigue crack growth behavior.

  3. The risk and prognostic impact of definite stent thrombosis or in-stent restenosis after coronary stent implantation

    DEFF Research Database (Denmark)

    Thayssen, Per; Jensen, Lisette Okkels; Lassen, Jens Flensted;

    2012-01-01

    of death (HR=2.71 [95% CI: 1.72-4.27]) compared to cases without stent thrombosis. In-stent restenosis had no substantial impact (HR=1.17 [95% CI: 0.79-1.75]). However, in-stent restenosis presenting as non-ST-segment elevation myocardial infarction (NSTEMI) was associated with a greater mortality risk...

  4. Biodegradability of Plastics

    OpenAIRE

    Yutaka Tokiwa; Calabia, Buenaventurada P.; Charles U. Ugwu; Seiichi Aiba

    2009-01-01

    Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical ...

  5. Polymer material biodegradation

    OpenAIRE

    B. Grabowska

    2010-01-01

    Data from literature was used to discuss the impact of external factors (stress, radiation, temperature, ultrasounds, biological organisms) on the course of polymer material degradation. Polymer materials, in widespread use for over a dozen years, constitute a serious environmental problem. This is why their susceptibility to biodegradation is researched. Work on biodegradable polymers concernsmodifying their structure to bring their physical and chemical properties closer to plastics in prac...

  6. Chlamydia trachomatis in cervicitis and urethritis in women.

    Science.gov (United States)

    Paavonen, J; Vesterinen, E

    1982-01-01

    In the Scandinavian countries today, Chlamydia trachomatis seems to be the most important cause of sexually transmitted diseases. Although C. trachomatis is most prevalent in symptomatic women and in persons visiting venereal disease clinics, the asymptomatic carrier rate, particularly in young women, appears to be surprisingly high. In addition to young age and level of sexual activity, the use of oral contraceptives and the presence of cervical ectopy are important risk factors for chlamydial infection. Chlamydial cervicitis often is characterized by a hypertrophic follicular appearance, with severe edema, erythema, friability, and endocervical mucopurulent discharge. On colposcopy, an atypical transformation zone is frequently observed. Papanicolaou smears taken from C. trachomatis culture-positive patients often reveal benign atypias and dyskaryotic changes. C. trachomatis, therefore, being a venereally transmitted intracellular organism, may well play a role in the development of cervical intraepithelial neoplasia (CIN). Future studies on patients with cytological atypias, therefore, also should include tests for C. trachomatis. Prospective studies are needed to determine the natural history and outcome of C. trachomatis-associated atypias and their behavior after adequate therapy. A large proportion of C. trachomatis-infected women also are culture-positive from the urethra. The demonstration that C. trachomatis is a common causative agent of acute urethral syndrome (also called abacterial urethritis, dysuria-pyuria syndrome) in women has been a valuable contribution. The diagnosis of pyuria in a patient with abacterial dysuria is of critical importance, since it suggests a chlamydial etiology and thus is a potentially treatable condition.

  7. Outcome of children with posterior urethral valves: Prognostic factors

    Directory of Open Access Journals (Sweden)

    R A Kukreja

    2001-01-01

    Full Text Available Posterior urethral valves present with a wide spectrum of renal and bladder pathology. These changes may per-sist despite successful treatment of the primary obstruc-tion, leading to a gradual progress towards renal insf ciency. This study reviews retrospectively a series of 70 children with posterior urethral valves who pre-sented at our institute over the last 10 years, with an aim to identify the prognostic factors and help in defining the end result and implicating the correct treatment proto-col. These included age at presentation and intervention (less than or more than 2 years, recurrent urosepsis, pres-ence of vesico-ureteric reflux, renal parenchymal dam-age as seen on ultrasound, vesical dysfunction and the nadir serum creatinine level. 29% of children had renal insufficiency at the end of 3-years′ follow-up. Factors important in the progression towards renal insufficiency were evaluated. Factors found to be statistically signifi-cant with a p value < 0.05 were age at intervention more than 2 years, recurrent urosepsis, bilateral high grade vesico-ureteric reflex, bilateral parenchymal damage as seen on ultrasonography and nadir serum creatinine of more than 0.8 mg%.

  8. Urethral metastasis of lung carcinoma with germinative cell features

    Directory of Open Access Journals (Sweden)

    Tefilli Marcos V.

    2003-01-01

    Full Text Available INTRODUCTION: We present the case of a patient with urethral metastasis of a lung carcinoma with germinative cell features. CASE REPORT: A White, 57-year old man underwent urologic assessment due to gross hematuria. Patient was being treated with chemotherapy and radiotherapy during the past 3 months due to primary carcinoma of the lung with brain metastasis. Urethrocistoscopy and nuclear magnetic resonance imaging revealed a stenosing mass invading the bulbomembranous urethra. No other tumor was found. Biopsy specimens, obtained from the lung, brain and urethra tumors, revealed the same neoplasia, with definitive diagnosis being undifferentiated giant cell carcinoma of the lung with germinative features. Considering his clinical condition and poor prognosis, a decision was made to treat the patient only clinically. Clinical conditions deteriorated and the patient evolved to death within 3 months. COMMENTS: As far as we were able to access, urethral metastasis from lung carcinoma had never been described in the indexed literature. Due to the extremely limited experience with these tumors, there is not a defined treatment and the prognosis remains quite poor.

  9. Urethral dysfunction in female mice with estrogen receptor β deficiency.

    Directory of Open Access Journals (Sweden)

    Yung-Hsiang Chen

    Full Text Available Estrogen has various regulatory functions in the growth, development, and differentiation of the female urogenital system. This study investigated the roles of ERβ in stress urinary incontinence (SUI. Wild-type (ERβ(+/+ and knockout (ERβ(-/- female mice were generated (aged 6-8 weeks, n = 6 and urethral function and protein expression were measured. Leak point pressures (LPP and maximum urethral closure pressure (MUCP were assessed in mice under urethane anesthesia. After the measurements, the urethras were removed for proteomic analysis using label-free quantitative proteomics by nano-liquid chromatography-mass spectrometry (LC-MS/MS analysis. The interaction between these proteins was further analysed using MetaCore. Lastly, Western blot was used to confirm the candidate proteins. Compared with the ERβ(+/+ group, the LPP and MUCP values of the ERβ(-/- group were significantly decreased. Additionally, we identified 85 differentially expressed proteins in the urethra of ERβ(-/- female mice; 57 proteins were up-regulated and 28 were down-regulated. The majority of the ERβ knockout-modified proteins were involved in cell-matrix adhesion, metabolism, immune response, signal transduction, nuclear receptor translational regelation, and muscle contraction and development. Western blot confirmed the up-regulation of myosin and collagen in urethra. By contrast, elastin was down-regulated in the ERβ(-/- mice. This study is the first study to estimate protein expression changes in urethras from ERβ(-/- female mice. These changes could be related to the molecular mechanism of ERβ in SUI.

  10. Visualization of Stent Lumen in MR Imaging: Relationship with Stent Design and RF Direction

    Directory of Open Access Journals (Sweden)

    Ohno,Seiichiro

    2012-06-01

    Full Text Available Magnetic resonance imaging (MRI visualization of metallic stent lumens is possible if the stent structure counteracts eddy currents in the lumen induced by the radio frequency magnetic field, B1. To examine the effectiveness of various stent designs in counteracting eddy currents, we anchored eight copper stent models and 2 commercially available nickel-titanium alloy (Nitinol stents in a gel phantom, perpendicular or parallel to the direction of B1. A mesh stent lumen showed hypointensity irrespective of its alignment relative to B1. A solenoid stent lumen showed hypointensity with the stent axis parallel to B1, but it had the same signal intensity as outside the lumen when perpendicular to B1. A Moebius stent lumen showed no signal reduction, irrespective of alignment relative to B1. Lumens of the commercially available stents showed hypointensity regardless of alignment relative to B1. Computer simulation revealed that the signal intensities of the stents corresponded to magnetic flux densities of B1 in the stents, which are modified by the structure of the stent. While in vivo MRI viewing of a Moebius stent lumen is likely possible regardless of axis alignment, inherent structural weakness may be problematic. As a more practical choice, the solenoid stent is easier to manufacture and generates no hypointensive signal when the axis is parallel to B0.

  11. Refining stent technologies for femoral interventions.

    Science.gov (United States)

    Bosiers, M; Deloose, K; Callaert, J; Maene, L; Keirse, K; Verbist, J; Peeters, P

    2012-08-01

    Stents were created as a mechanical scaffold to prevent vessel recoil and luminal renarrowing after percutaneous transluminal angioplasty (PTA). In femoropopliteal arteries, indication for stent implantation remains a topic much debated on, especially in long lesion configurations. Ever since the first stents were introduced on the market, in-stent restenosis (ISR) has been an important issue. The evolution in stent design has known a major progression in the last decades from the first generation of stents, plagued with high fracture rates and low primary patency rates, to the design of newer stents to tackle these outcomes. More flexible and longer stents decreased the high fracture rates and drug-eluting stents offered a solution to the restenosis rates by local drug application. The difficult recrossibility of the lesion because of the presence of a permanent vascular scaffold is an obstacle that the drug-coated balloon (DCB) overcomes. Future perspectives in the treatment of femoropopliteal lesions are found in the bioresorbable stent implantation. The bioresorbable stent combines the advantages of a drug-eluting scaffolding stent without the remainder of a foreign object in the long-term. Further investigations in this area will eventually evolve in the creation of a superior endovascular treatment modality with high long-term patency rates and minimal detriments.

  12. Migration of forgotten stent into renal pelvis.

    Science.gov (United States)

    Giridhar, Venkatesh; Natarajan, Kumaresan; Hegde, Padmaraj

    2011-04-01

    Stent migration is a well recognized complication of forgotten stents, but migration into the renal pelvis is rarely documented. We present a case of migration and coiling of a forgotten stent in the renal pelvis, and discuss briefly, the etiological factors for the phenomenon and associated problems in management.

  13. 21 CFR 884.3900 - Vaginal stent.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vaginal stent. 884.3900 Section 884.3900 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... stent. (a) Identification. A vaginal stent is a device used to enlarge the vagina by stretching, or...

  14. Incidence and predictors of coronary stent thrombosis

    DEFF Research Database (Denmark)

    D'Ascenzo, Fabrizio; Bollati, Mario; Clementi, Fabrizio

    2013-01-01

    Stent thrombosis remains among the most feared complications of percutaneous coronary intervention (PCI) with stenting. However, data on its incidence and predictors are sparse and conflicting. We thus aimed to perform a collaborative systematic review on incidence and predictors of stent...

  15. What to Expect After a Stent Procedure

    Science.gov (United States)

    ... time after the stent procedure. Your doctor will let you know when you can go back to your normal activities. Metal detectors used in airports and other screening areas don't affect stents. Your stent shouldn't cause metal ...

  16. Isolation of Haemophilus influenzae and Haemophilus parainfluenzae in urethral exudates from men with acute urethritis: a descriptive study of 52 cases.

    Science.gov (United States)

    Deza, Gustavo; Martin-Ezquerra, Gemma; Gómez, Julià; Villar-García, Judit; Supervia, August; Pujol, Ramon M

    2016-02-01

    To describe the clinical characteristics and therapeutic outcomes from male patients diagnosed of Haemophilus spp urethritis. A chart review of patients who presented to our hospital from January 2013 to December 2014 with symptoms of acute urethritis in which Haemophilus spp was isolated in their urethral samples was performed. Haemophilus spp was isolated in 52 out of 413 urethral samples (12.6%) received in our laboratory from patients with symptoms of acute urethritis during the study period. Seven cases corresponded to Haemophilus influenzae and 45 cases to Haemophilus parainfluenzae. The most common clinical presentation was mucopurulent urethral discharge (71%). Eight per cent were HIV-infected patients, and 60% were men who have sex with men. Haemophilus spp was isolated as a single pathogen in 6.8% (28 of 413) of cases. Seventeen per cent of Haemophilus spp were β-lactamase producers. All patients reported having practiced unprotected insertive oral sex the month before consultation, and five of them denied having had another sexual contact apart from this exposure. In all cases in which follow-up was available, empirical treatment achieved a complete clinical resolution. Haemophilus spp was considered a pathogen in at least 6.8% of the patients from the evaluated area. It affected men regardless their sexual orientation or HIV status. Unprotected oral sex could play a role in its transmission. The limitations of the study (small sample size and lack of a representative control group) do not allow to prove the true pathogenic role of Haemophilus spp in acute urethritis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  17. Elastin-Coated Biodegradable Photopolymer Scaffolds for Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Rossella Barenghi

    2014-01-01

    Full Text Available One of the main open issues in modern vascular surgery is the nonbiodegradability of implants used for stent interventions, which can lead to small caliber-related thrombosis and neointimal hyperplasia. Some new, resorbable polymeric materials have been proposed to substitute traditional stainless-steel stents, but so far they were affected by poor mechanical properties and low biocompatibility. In this respect, a new material, polypropylene fumarate (PPF, may be considered as a promising candidate to implement the development of next generation stents, due to its complete biodegradability, and excellent mechanical properties and the ease to be precisely patterned. Besides all these benefits, PPF has not been tested yet for vascular prosthesis, mainly because it proved to be almost inert, while the ability to elicit a specific biological function would be of paramount importance in such critical surgery applications. Here, we propose a biomimetic functionalization process, aimed at obtaining specific bioactivation and thus improved cell-polymer interaction. Porous PPF-based scaffolds produced by deep-UV photocuring were coated by elastin and the functionalized scaffolds were extensively characterized, revealing a stable bound between the protein and the polymer surface. Both 3T3 and HUVEC cell lines were used for in vitro tests displaying an enhancement of cells adhesion and proliferation on the functionalized scaffolds.

  18. "Virtual" in-vivo bench test for bifurcation stenting with "StentBoost".

    Science.gov (United States)

    Agostoni, Pierfrancesco; Verheye, Stefan; Vermeersch, Paul; Cornelis, Kristoff; Van Langenhove, Glenn

    2009-04-01

    "StentBoost" is a new angiographic technique that allows improved angiographic visualization of stents deployed in coronary arteries, by enhancing the X-ray focus of the region where the stent is placed. Using this technique we were able to assess the deformation and the expansion of a stent deployed to treat a bifurcation lesion between the mid-left anterior descending (LAD) artery and a big second diagonal branch, during sequential inflations of: (1) the stent per se in the LAD, (2) the ostium of the diagonal branch through the stent struts, (3) the stent again with a non compliant balloon, and (4) both branches with the kissing balloon technique. "StentBoost" guided our clinical and angiographic decision-making process and allowed us to create a "virtual" bench test of the stent deployed at the level of the bifurcation treated.

  19. Continuum damage model for bioresorbable magnesium alloy devices - Application to coronary stents.

    Science.gov (United States)

    Gastaldi, D; Sassi, V; Petrini, L; Vedani, M; Trasatti, S; Migliavacca, F

    2011-04-01

    The main drawback of a conventional stenting procedure is the high risk of restenosis. The idea of a stent that "disappears" after having fulfilled its mission is very intriguing and fascinating, since it can be expected that the stent mass decreases in time to allow the gradual transmission of the mechanical load to the surrounding tissues owing to controlled dissolution by corrosion. Magnesium and its alloys are appealing materials for designing biodegradable stents. The objective of this work is to develop, in a finite element framework, a model of magnesium degradation that is able to predict the corrosion rate, thus providing a valuable tool for the design of bioresorbable stents. Continuum damage mechanics is suitable for modeling several damage mechanisms, including different types of corrosion. In this study, the damage is assumed to be the superposition of stress corrosion and uniform microgalvanic corrosion processes. The former describes the stress-mediated localization of the corrosion attack through a stress-dependent evolution law, while the latter affects the free surface of the material exposed to an aggressive environment. Comparisons with experimental tests show that the developed model can reproduce the behavior of different magnesium alloys subjected to static corrosion tests. The study shows that parameter identification for a correct calibration of the model response on the results of uniform and stress corrosion experimental tests is reachable. Moreover, three-dimensional stenting procedures accounting for interaction with the arterial vessel are simulated, and it is shown how the proposed modeling approach gives the possibility of accounting for the combined effects of an aggressive environment and mechanical loading.

  20. One-stage urethral reconstruction using colonic mucosa graft:an experimental and clinical study

    Institute of Scientific and Technical Information of China (English)

    Yue-Min Xu; Yong Qiao; Ying-Long Sa; Jiong Zhang; Hui-Zhen Zhang; Xin-Ru Zhang; Deng-Long Wu; Rong Chen

    2003-01-01

    AIM: To investigate the possibility of urethral reconstructionwith a free colonic mucosa graft and to present ourpreliminary experience with urethral substitution using a freegraft of colonic mucosa for treatment of 7 patients withcomplex urethral stricture of a long segment.METHODS: Ten female dogs underwent a procedure inwhich the urethral mucosa was totally removed andreplaced with a free graft of colonic mucosa. A urodynamicstudy was performed before the operation and sacrifice.The dogs were sacrificed 8 to 16 weeks after the operationfor histological examination of urethra. Besides, 7 patientswith complex urethral stricture of a long segment weretreated by urethroplasty with the use of a colonic mucosalgraft. The cases had undergone an average of 3 previousunsuccessful repairs. Urethral reconstruction with a freegraft of colonic mucosa ranged from 10 to 17 cm (mean13.1 cm). Follow-up included urethrography, urethroscopyand uroflowmetry.RESULTS: Urethral stricture developed in 1 dog. The resultsof urodynamic studies showed that the difference in themaximum urethral pressure between the pre-operation andpre-sacrifice in the remaining 9 dogs was not of significance(P>0.05). Histological examination revealed that the colonicfree mucosa survived inside the urethral lumen of the 10experimental dogs. Plicae surface and unilaminar cylindricepithelium of the colonic mucosa was observed in dogssacrificed 8 weeks after the operation. The plicae surfaceand unilaminar cylindric epithelium of the colonic mucosawas not observed, and metaplastic transitional epitheliumcovered a large proportion of the urethral mucosa in dogssacrificed 12 weeks after the operation. Clinically, the patientswere followed up for 3-18 months postoperatively (mean8.5 months). Meetal stenosis was developed in 1 patient 3months postoperatively and needed reoperation. The patientwas voiding very well with urinary peak flow 28.7 ml/s duringthe follow-up of 9 months after reoperation. The

  1. A Simple Technique to Facilitate Treatment of Urethral Strictures with Optical Internal Urethrotomy

    Directory of Open Access Journals (Sweden)

    Konstantinos Stamatiou

    2014-01-01

    Full Text Available Urethral stricture is a common condition that can lead to serious complications such as urinary infections and renal insufficiency secondary to urinary retention. Treatment options include catheterization, urethroplasty, endoscopic internal urethrotomy, and dilation. Optical internal urethrotomy offers faster recovery, minimal scarring, and less risk of infection, although recurrence is possible. However, technical difficulties associated with poor visualization of the stenosis or of the urethral lumen may increase procedural time and substantially increase the failure rates of internal urethrotomy. In this report we describe a technique for urethral catheterization via a suprapubic, percutaneous approach through the urinary bladder in order to facilitate endoscopic internal urethrotomy.

  2. Parameatal urethral cyst of glans penis in children – a report of three cases

    Directory of Open Access Journals (Sweden)

    Mrinal Gupta

    2015-10-01

    Full Text Available Parameatal urethral cysts are a rare benign condition usually seen in males. They are usually asymptomatic but may produce symptoms like difficulty in micturition, pain during intercourse, urinary retention and distortion of the urinary stream. We report three cases of parameatal urethral cyst in young males presenting as a spherical clear fluid filled cystic lesions over the external urethral meatus, causing distortion of the urinary stream and poor cosmesis. Histological examination of the excised cyst showed a monolocular cyst lined with pseudo-stratified epithelium with no evidence of inflammation. Complete surgical excision of the cysts was done and no recurrence was observed at follow-up.

  3. Inductive antenna stent: design, fabrication and characterization

    Science.gov (United States)

    Rashidi Mohammadi, Abdolreza; Ali, Mohamed Sultan Mohamed; Lappin, Derry; Schlosser, Colin; Takahata, Kenichi

    2013-02-01

    This paper describes the design, fabrication, and electromechanical characteristics of inductive stents developed for intelligent stent applications. The stents, fabricated out of 316L stainless-steel tubes using laser machining, are patterned to have zigzag loops without bridge struts, and when expanded, become a helix-like structure. Highly conductive metals such as copper and gold are coated on the stents to improve their inductive/antenna function. The Q-factor of the stent is shown to increase by a factor of 7 at 150 MHz with copper coating. The expansion of the stent from 2 to 4 mm diameter results in a 3.2× increase in the inductance, obtaining ˜1 µH at a similar frequency. The stent passivated by Parylene-C film is used to characterize its resonance in different media including saline. The copper-coated inductive stent exhibits a 2.4× radial stiffness for 1 mm strain as well as a 16× bending compliance compared with a commercial stent, each of which is potentially beneficial in preventing/mitigating stent failures such as recoil as well as enabling easier navigation through intricate blood vessels. The mechanical stiffness may be tailored by adjusting stent-wire thickness while maintaining necessary coating thickness to achieve particular mechanical requirements and high inductive performance simultaneously.

  4. Molecularly Imprinted Biodegradable Nanoparticles

    Science.gov (United States)

    Gagliardi, Mariacristina; Bertero, Alice; Bifone, Angelo

    2017-01-01

    Biodegradable polymer nanoparticles are promising carriers for targeted drug delivery in nanomedicine applications. Molecu- lar imprinting is a potential strategy to target polymer nanoparticles through binding of endogenous ligands that may promote recognition and active transport into specific cells and tissues. However, the lock-and-key mechanism of molecular imprinting requires relatively rigid cross-linked structures, unlike those of many biodegradable polymers. To date, no fully biodegradable molecularly imprinted particles have been reported in the literature. This paper reports the synthesis of a novel molecularly- imprinted nanocarrier, based on poly(lactide-co-glycolide) (PLGA) and acrylic acid, that combines biodegradability and molec- ular recognition properties. A novel three-arm biodegradable cross-linker was synthesized by ring-opening polymerization of glycolide and lactide initiated by glycerol. The resulting macromer was functionalized by introduction of end-functions through reaction with acryloyl chloride. Macromer and acrylic acid were used for the synthesis of narrowly-dispersed nanoparticles by radical polymerization in diluted conditions in the presence of biotin as template molecule. The binding capacity of the imprinted nanoparticles towards biotin and biotinylated bovine serum albumin was twentyfold that of non-imprinted nanoparti- cles. Degradation rates and functional performances were assessed in in vitro tests and cell cultures, demonstrating effective biotin-mediated cell internalization.

  5. Molecularly Imprinted Biodegradable Nanoparticles

    Science.gov (United States)

    Gagliardi, Mariacristina; Bertero, Alice; Bifone, Angelo

    2017-01-01

    Biodegradable polymer nanoparticles are promising carriers for targeted drug delivery in nanomedicine applications. Molecu- lar imprinting is a potential strategy to target polymer nanoparticles through binding of endogenous ligands that may promote recognition and active transport into specific cells and tissues. However, the lock-and-key mechanism of molecular imprinting requires relatively rigid cross-linked structures, unlike those of many biodegradable polymers. To date, no fully biodegradable molecularly imprinted particles have been reported in the literature. This paper reports the synthesis of a novel molecularly- imprinted nanocarrier, based on poly(lactide-co-glycolide) (PLGA) and acrylic acid, that combines biodegradability and molec- ular recognition properties. A novel three-arm biodegradable cross-linker was synthesized by ring-opening polymerization of glycolide and lactide initiated by glycerol. The resulting macromer was functionalized by introduction of end-functions through reaction with acryloyl chloride. Macromer and acrylic acid were used for the synthesis of narrowly-dispersed nanoparticles by radical polymerization in diluted conditions in the presence of biotin as template molecule. The binding capacity of the imprinted nanoparticles towards biotin and biotinylated bovine serum albumin was twentyfold that of non-imprinted nanoparti- cles. Degradation rates and functional performances were assessed in in vitro tests and cell cultures, demonstrating effective biotin-mediated cell internalization. PMID:28071745

  6. Local Delivery of Antiproliferative Agents via Stents

    Directory of Open Access Journals (Sweden)

    Hyuck Joon Kwon

    2014-03-01

    Full Text Available A stent is a medical device for serving as an internal scaffold to maintain or increase the lumen of a body conduit. Stent placement has become a primary treatment option in coronary artery disease for more than the last two decades. The stenting is also currently used for relieving the symptoms of narrowed lumen of nonvascular organs, such as esophagus, trachea and bronchi, small and large intestines, biliary, and urinary tract. Local delivery of active pharmaceutical agents via the stents can not only enhance healing of certain diseases, but it can also help decrease the potential risk of the stenting procedure to the surrounding tissue. In this review, we focus on reviewing a variety of drug-impregnated stents and local drug delivery systems using the stents.

  7. [Absorbable coronary stents. New promising technology].

    Science.gov (United States)

    Erbel, Raimund; Böse, Dirk; Haude, Michael; Kordish, Igor; Churzidze, Sofia; Malyar, Nasser; Konorza, Thomas; Sack, Stefan

    2007-06-01

    Coronary stent implantation started in Germany 20 years ago. In the beginning, the progress was very slow and accelerated 10 years later. Meanwhile, coronary stent implantation is a standard procedure in interventional cardiology. From the beginning of permanent stent implantation, research started to provide temporary stenting of coronary arteries, first with catheter-based systems, later with stent-alone technology. Stents were produced from polymers or metal. The first polymer stent implantation failed except the Igaki-Tamai stent in Japan. Newly developed absorbable polymer stents seem to be very promising, as intravascular ultrasound (IVUS) and optical coherence tomography have demonstrated. Temporary metal stents were developed based on iron and magnesium. Currently, the iron stent is tested in peripheral arteries. The absorbable magnesium stent (Biotronik, Berlin, Germany) was tested in peripheral arteries below the knee and meanwhile in the multicenter international PROGRESS-AMS (Clinical Performance and Angiographic Results of Coronary Stenting with Absorbable Metal Stents) study. The first magnesium stent implantation was performed on July 30, 2004 after extended experimental testing in Essen. The magnesium stent behaved like a bare-metal stent with low recoil of 5-7%. The stent struts were absorbed when tested with IVUS. Stent struts were not visible by fluoroscopy or computed tomography (CT) as well as magnetic resonance imaging (MRI). That means, that the magnesium stent is invisible and therefore CT and MRI can be used for imaging of interventions. Only using micro-CT the stent struts were visible. The absorption process could be demonstrated in a patient 18 days after implantation due to suspected acute coronary syndrome, which was excluded. IVUS showed a nice open lumen. Stent struts were no longer visible, but replaced by tissue indicating the previous stent location. Coronary angiography after 4 months showed an ischemia-driven target lesion

  8. Prevention of stent thrombosis: challenges and solutions

    Directory of Open Access Journals (Sweden)

    Reejhsinghani R

    2015-01-01

    Full Text Available Risheen Reejhsinghani, Amir S LotfiDivision of Cardiology, Baystate Medical Center, Springfield, MA, USAAbstract: Stent thrombosis is an uncommon but serious complication which carries with it significant mortality and morbidity. This review analyzes the entity of stent thrombosis from a historical and clinical perspective, and chronicles the evolution of this condition through the various generations of stent development, from bare metal to first-generation, second-generation, and third-generation drug-eluting stents. It also delineates the specific risk factors associated with stent thrombosis and comprehensively examines the literature related to each of these risks. Finally, it highlights the preventative strategies that can be garnered from the existing data, and concludes that a multifactorial approach is necessary to combat the occurrence of stent thrombosis, with higher risk groups, such as patients with ST segment elevation myocardial infarction, meriting further research.Keywords: stent thrombosis, preventative strategies, post-procedural myocardial infarction

  9. Stenting for restenotic lesions with the BARD XT stent.

    Science.gov (United States)

    Rahel, Braim M; Suttorp, Maarten J; Te Riele, Hans A; Bal, Egbert T; Ernst, Sjef M; Mast, E Gijs; Ten Berg, Jurriën M; Kelder, Johannes C; Plokker, H W Thijs

    2003-06-01

    Conventional PTCA for the treatment of restenotic lesions is associated with a high rate of recurrence (30-50%). Primary stenting decreases the restenosis rate at long-term follow-up. One-hundred consecutive patients with restenosis received a Bard XT stent. Follow-up angiography was performed after 6 months. Angiograms were compared by means of computed quantitative analysis. The mean pretreatment reference diameter was 2.88 +/- 0.51 mm. The mean minimal luminal diameter (MLD) increased from 1.09 +/- 0.57 mm to 2.70 +/- 0.44 mm. The percent diameter stenosis decreased from 66 +/- 13% to 15 +/- 10%. The procedural success rate was 99%. At 6 month follow-up repeat angiography was performed in 86 patients. The mean MLD was 1.74 +/- 0.67 mm with a mean diameter stenosis of 41 +/- 20%. Residual anginal complaints were reported in 29% of patients. In-stent restenosis (defined as diameter stenosis of more than 50%) occurred in 18% of the patients. Placement of the Bard XT stent in restenotic lesions is feasible, has an excellent short term outcome and yields a favorable result at 6 month follow-up angiography.

  10. Forgotten ureteral stents: who's at risk?

    Science.gov (United States)

    Divakaruni, Naveen; Palmer, Cristina J; Tek, Peter; Bjurlin, Marc A; Gage, Mistry K; Robinson, Jed; Lombardo, Lindsay; Wille, Mark A; Hollowell, Courtney M P

    2013-08-01

    The sequelae from forgotten stents carry significant morbidity and costs. In this study, we attempt to identify potential risk factors that may make patients less likely to follow up for stent removal so that more effective prevention efforts may be directed at these persons. A single-institution retrospective analysis of 187 consecutive patients who had stents placed between January 2010 and December 2010 was performed. Chart review was conducted to see if patients had undergone stent removal beyond the intended maximal stent life (MSL). Patients who were lost to follow-up were contacted to determine if stents were overdue. Logistic regression was performed to determine risk factors. Of the 187 patients who had stents placed, 147 had the stent removed before MSL and 28 had stents removed after the MSL. Twelve patients could not be contacted and were excluded from the analysis. Within our cohort of 175 patients, 48% were males, 73% were minorities (33% Latino, 30% Black, 8% Asian, and 2% Native American), 39% did not speak English, 79% were unemployed, 73% were uninsured, and 35% were married. Among the patients with forgotten stents, 68% were male, 64% were minorities (32% Latino, 29% Black, 4% Native American, and 0% Asian), 82% were unemployed, 39% did not speak English, 93% were uninsured, and 43% were married. Multivariate regression analysis demonstrated that uninsured patients (odds ratio [OR], 6.3; 95% confidence interval [CI], 1.4-28.2; P value 0.01) and males (OR, 2.8; CI, 1.2-6.8; P=0.02) had statistically significant associations with forgotten stents. Men were 2.8 times more likely to have forgotten stents than females. Patients without health insurance were six times more likely to have forgotten stents than patients with insurance. As efforts are made to prevent forgotten stents, increased attention should be given to these higher-risk patient populations.

  11. Endourological Management of Forgotten Encrusted Ureteral Stents

    Directory of Open Access Journals (Sweden)

    Kusuma V. R. Murthy

    2010-08-01

    Full Text Available PURPOSE: To present our experience and discuss the various endourological approaches for treating forgotten encrusted ureteral stents associated with stone formation. MATERIALS AND METHODS: From July 2006 to December 2008, 14 patients (11 men and 3 women with encrusted ureteral stents were analyzed. The average indwelling time of the stent was 4.9 years (range 1 to 12. Plain-film radiography was used to evaluate encrustation, stone burden, and fragmentation of the stents. Intravenous urogram and a Tc99m diethylene triamine penta acetic-acid renogram was used to assess renal function. RESULTS: In seven patients, the entire stent was encrusted, in three patients the encrustation was confined to the ureteral and lower coil part of the stent, two patients had encrustation of the lower coil, and minimal encrustation was observed in two patients. Percutaneous nephrolithotomy was performed in 5 cases and retrograde ureteroscopy with intra-corporeal lithotripsy in 9 patients. Cystolithotripsy was used to manage the distal coil of the encrusted stent in eight patients. Simple cystoscopic removal of the stents with minimal encrustation was carried-out in two cases. Looposcopy and removal of the stent was performed in one patient with an ileal conduit and retained stent. Only one patient required open surgical removal of the stent. Thirteen out of 14 patients were rendered stone and stent free in one session. All except two stents were removed intact and stone analysis of encrustation and calcification revealed calcium oxalate and calcium phosphate in the majority of the cases. CONCLUSION: Endourological management of forgotten encrusted stents is highly successful and often avoids the need for open surgical techniques.

  12. Drug eluting biliary stents to decrease stent failure rates: Areview of the literature

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    Biliary stenting is clinically effective in relieving bothmalignant and non-malignant obstructions. However, thereare high failure rates associated with tumor ingrowth andepithelial overgrowth as well as internally from biofilmdevelopment and subsequent clogging. Within the lastdecade, the use of prophylactic drug eluting stents as ameans to reduce stent failure has been investigated. Inthis review we provide an overview of the current researchon drug eluting biliary stents. While there is limited humantrial data regarding the clinical benefit of drug elutingbiliary stents in preventing stent obstruction, recentresearch suggests promise regarding their safety andpotential efficacy.

  13. Clinical experience in coronary stenting with the Vivant Z Stent.

    Science.gov (United States)

    Chee, K H; Siaw, F S; Chan, C G; Chong, W P; Imran, Z A; Haizal, H K; Azman, W; Tan, K H

    2005-06-01

    This single centre study was designed to demonstrate feasibility, safety and efficacy of the Vivant Z stent (PFM AG, Cologne, Germany). Patients with de novo lesion were recruited. Coronary angioplasty was performed with either direct stenting or after balloon predilatation. Repeated angiogram was performed 6 months later or earlier if clinically indicated. Between January to June 2003, a total of 50 patients were recruited (mean age 55.8 +/- 9 years). A total of 52 lesions were stented successfully. Mean reference diameter was 2.77 mm (+/-0.59 SD, range 2.05-4.39 mm) with mean target lesion stenosis of 65.5% (+/-11.6 SD, range 50.1-93.3%). Forty-six lesions (88.5%) were American College of Cardiologist/American Heart Association class B/C types. Direct stenting was performed in 18 (34.6%) lesions. Mean stent diameter was 3.18 mm (+/-0.41 SD, range 2.5-4 mm), and mean stent length was 14.86 mm (+/-2.72 SD, range 9-18 mm). The procedure was complicated in only one case which involved the loss of side branch with no clinical sequelae. All treated lesions achieved Thrombolysis In Myocardial Infarction 3 flow. Mean residual diameter stenosis was 12.2% (+/-7.55 SD, range 0-22.6%) with acute gain of 1.72 mm (+/-0.50 SD, range 0.5-2.8). At 6 months, there was no major adverse cardiovascular event. Repeated angiography after 6 months showed a restenosis rate of 17% (defined as >50% diameter restenosis). Mean late loss was 0.96 mm (+/-0.48 SD) with loss index of 0.61 (+/-0.38 SD). The restenosis rate of those lesions less than 3.0 mm in diameter was 22.2% compared with 6.25% in those lesions more than 3.0 mm in diameter. The Vivant Z stent was shown to be safe and efficacious with low restenosis rate in de novo coronary artery lesion.

  14. Urethral polyp in a 1-month-old child

    Energy Technology Data Exchange (ETDEWEB)

    Beluffi, Giampiero [Department of Radiodiagnosis, IRCCS Policlinico S. Matteo, Section of Paediatric Radiology, Piazzale Golgi, 2, I-27100, Pavia PV (Italy); Berton, Francesca; Gola, Giada [University of Pavia, IRCCS Policlinico S. Matteo, Institute of Radiology, Pavia (Italy); Chiari, Giorgio; Romano, Piero; Cassani, Ferdinando [IRCCS Policlinico S. Matteo, Division of Paediatric Surgery, Pavia (Italy)

    2005-07-01

    Urethral polyps are a rare finding in children, particularly in the very young. They are suspected by the presence of various clinical signs such as obstruction, voiding dysfunction and haematuria. There is an association with other urinary tract congenital anomalies. They are usually benign fibro-epithelial lesions with no tendency to recur and are treated by surgical ablation, fulguration or laser therapy. We report a 1-month-old boy with an antenatally diagnosed left ectopic pelvic kidney, postnatal urinary tract infection and no clinical signs of obstruction. Voiding cystourethrography to exclude vesico-ureteric reflux showed a trabeculated bladder and a mobile filling defect in the posterior urethra. Owing to its large size, cystotomy was necessary to remove the polyp successfully. (orig.)

  15. Urethral masturbation and sexual disinhibition in dementia: a case report.

    Science.gov (United States)

    Rosenthal, Michal; Berkman, Pinhas; Shapira, Adi; Gil, Israel; Abramovitz, Jancu

    2003-01-01

    Urethral masturbation and sexual disinhibition as manifestations of behavioral and psychological symptoms of dementia (BPSD) are described in a 90-year-old patient who repeatedly self-inserted foreign bodies into his urethra. A diagnosis was made of late onset sexual disinhibition and hypersexuality in a patient with Dementia of the Alzheimer Type. Significant reduction of his sexual behavior was achieved with low doses of haloperidol. Similar symptoms are noted in Pick's disease, other fronto-temporal lesions, mania and following a seizure or treatment of Parkinson's disease, and have been described as Kluver-Busy-type. Clinicians should consider this diagnosis when investigating dysuria, cystitis, haematuria and urinary tract infections even in the very old.

  16. Female urethral diverticulum associated with a large urinary calculus

    Directory of Open Access Journals (Sweden)

    Alexandre Oliveira Rodrigues

    2009-12-01

    Full Text Available The diverticula of female urethra are very uncommon, but more frequently found between the third and fifth decade of life. Diverticula area mostly relate to repeated urinary infections of the periurethral glands or urethra’s trauma. The diverticula may cause infection, calculus formation and rarely endometriosis or cancer. A case of a 65-year old Caucasian female with vaginal mass over six months is herein reported. There was no urinary loss, urethral secretion or urinary symptoms.    A cystourethrography showed diverticula with calculus inside. The patient was submitted to surgery and dismissed from the hospital on the first postoperative day. The pathologic examination revealed no malignancy. In six months of follow-up, the patient was continent with no complaints.

  17. Green and biodegradable electronics

    Directory of Open Access Journals (Sweden)

    Mihai Irimia-Vladu

    2012-07-01

    Full Text Available We live in a world where the lifetime of electronics is becoming shorter, now approaching an average of several months. This poses a growing ecological problem. This brief review will present some of the initial steps taken to address the issue of electronic waste with biodegradable organic electronic materials. Many organic materials have been shown to be biodegradable, safe, and nontoxic, including compounds of natural origin. Additionally, the unique features of such organic materials suggest they will be useful in biofunctional electronics; demonstrating functions that would be inaccessible for traditional inorganic compounds. Such materials may lead to fully biodegradable and even biocompatible/biometabolizable electronics for many low-cost applications. This review highlights recent progress in these classes of material, covering substrates and insulators, semiconductors, and finally conductors.

  18. A method to determine the kink resistance of stents and stent delivery systems according to international standards

    OpenAIRE

    Brandt-Wunderlich Christoph; Schwerdt Christopher; Behrens Peter; Grabow Niels; Schmitz Klaus-Peter; Schmidt Wolfram

    2016-01-01

    The kink behavior of vascular stents is of particular interest for clinicians, stent manufacturers and regulatory as a kinked stent generates a lumen loss in the stented vessel and can lead to in-stent restenosis. In this study methods to determine the kink resistance of stents and stent delivery systems according to the ISO 25539-2 and FDA guidance no. 1545 were presented. The methods are applicable for balloon expandable stents as well as for self-expanding stents and determine the lumen lo...

  19. A method to determine the kink resistance of stents and stent delivery systems according to international standards

    Directory of Open Access Journals (Sweden)

    Brandt-Wunderlich Christoph

    2016-09-01

    Full Text Available The kink behavior of vascular stents is of particular interest for clinicians, stent manufacturers and regulatory as a kinked stent generates a lumen loss in the stented vessel and can lead to in-stent restenosis. In this study methods to determine the kink resistance of stents and stent delivery systems according to the ISO 25539-2 and FDA guidance no. 1545 were presented. The methods are applicable for balloon expandable stents as well as for self-expanding stents and determine the lumen loss and residual diameter change dependent on the specific bending radius.

  20. Stent malapposition, as a potential mechanism of very late stent thrombosis after bare-metal stent implantation: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Higuma, Takumi, E-mail: higuma@cc.hirosaki-u.ac.jp; Abe, Naoki; Hanada, Kenji; Yokoyama, Hiroaki; Tomita, Hirofumi; Okumura, Ken

    2014-04-15

    A 90-year-old man was admitted to our hospital with acute ST-segment elevation myocardial infarction. He had a history of post-infarction angina pectoris 79 months ago and had a bare-metal stent (BMS) implanted in the proximal left anterior descending artery at our hospital. Emergent coronary angiography demonstrated thrombotic occlusion in the previously stented segment. After catheter thrombectomy, antegrade flow was restored, but 90% stenosis with haziness persisted in the proximal and distal portions of the previously stented segment. Intravascular ultrasound imaging showed interstrut cavities or stent malapposition at the proximal and distal sites of stented segment. In close proximity to the sites, residual thrombi were also observed. Optical coherence tomography (OCT) demonstrated neither lipid-laden neointimal tissue nor rupture but clearly demonstrated residual thrombus adjacent to the malapposed region in addition to the stent malapposition. PCI with balloon was successfully performed and stent apposition was confirmed by OCT. Stent malapposition is an unusual mechanism of very late stent thrombosis after BMS implantation. OCT can clearly reveal the etiology of stent thrombosis.

  1. An in Vitro Twist Fatigue Test of Fabric Stent-Grafts Supported by Z-Stents vs. Ringed Stents

    Directory of Open Access Journals (Sweden)

    Jing Lin

    2016-02-01

    Full Text Available Whereas buckling can cause type III endoleaks, long-term twisting of a stent-graft was investigated here as a mechanism leading to type V endoleak or endotension. Two experimental device designs supported with Z-stents having strut angles of 35° or 45° were compared to a ringed control under accelerated twisting. Damage to each device was assessed and compared after different durations of twisting, with focus on damage that may allow leakage. Stent-grafts with 35° Z-stents had the most severe distortion and damage to the graft fabric. The 45° Z-stents caused less fabric damage. However, consistent stretching was still seen around the holes for sutures, which attach the stents to the graft fabric. Larger holes may become channels for fluid percolation through the wall. The ringed stent-graft had the least damage observed. Stent apexes with sharp angles appear to be responsible for major damage to the fabrics. Device manufacturers should consider stent apex angle when designing stent-grafts, and ensure their devices are resistant to twisting.

  2. [Diagnosis of urethritis in men. A 3-year review].

    Science.gov (United States)

    Orellana, M A; Gómez, M l; Sánchez, M T; Fernández-Chacón, T

    2009-06-01

    The aim of this study is to know the prevalence and tendency of microorganisms producing urethritis, in men, in the City Centre of Madrid. Cross-sectional study. The urethral samples of 1.248 men were analyzed, for 3 years. The samples were studied for: GRAM stain, when secretion exists; culture in habitual plates; detection of C. trachomatis, U. urealyticum and M. hominis, when there was suspicious, study of T. vaginalis and when suspicious injuries exist, study of virus Herpes simplex. The percentage of positive samples was 22.60%. The isolated microorganisms were: U. urealyticum 7.61%, N. gonorrhoeae 6.33%, C. trachomatis 4.81%, M. hominis 0.24%, H. parainfluenzae 1.76%, H. influenzae 1.12%, Candida spp 0.48%, S. pyogenes 0.16% and Herpes virus simplex (2) 0.08%. Two or more microorganisms were isolated in 1.68%. The percentage of positive samples in 2003 was 17.41% and N. gonorrhoeae the most frequent microorganism (6.22%). In 2004 was 25.57% and the most frequent U. urealyticum (10.18%). In 2005 the 24.50% of the samples were positive and U. urealyticum the most frequent (7.92%). The 79.41% of N. gonorrhoeae were susceptible to all antibiotics tested. It is not found resistance to ceftriaxone, claritromicine and amoxicilline/clavulanic acid. The 11.76% were betalactamase- producing. The 26.47% of Haemophilus spp. were betalactamase- producing and all strains were susceptible to cefotaxime. The isolated microorganisms most frequently were: U. urealyticum, N. gonorrhoeae and C. trachomatis. There is an increase of 7% of prevalence between the years 2003 and 2005. Ceftriaxone, claritromicine and amoxicilline/clavulanic acid were susceptible to all the strains studied and cefotaxime to all Haemophilus spp.

  3. Uretritis meningocóccica masculina Male meningococcal urethritis

    Directory of Open Access Journals (Sweden)

    Federico Díaz González

    1994-01-01

    Full Text Available

    Se presenta el caso de un hombre de 39 años que tuvo uretritis ocho días después de relación orogenital (felatio con una prostituta; de la secreción uretral se aisló Neisseria meningitidis, clasificada como del grupo B; la cepa no producía β lactamasa. El paciente fue tratado con ciprofloxacina y respondió satisfactoriamente; los controles ocho días después de terminar el tratamiento fueron negativos para Neisseria. La inmunofluorescencia para C. trachomatis fue negativa. Se hace una discusión del significado de la N. meningitidis en infecciones genitales.

    We report on the case of a 39 year-old white male who developed urethritis eight days after orogenital contact (fellatio with a prostitute. Group B N. meningitidis was recovered from the urethral secretion; the strain was negative for β lactamase production. Response to cyprofloxacin treatment was satisfactory. Control cultures for Neisseriawere negative eight days after completing treatment. At that moment direct immunofluorescence for Chlamydia trachomatis antigens were also negative. The significance of N. meningitidis in genital tract infections is discussed.

  4. Editorial: Biodegradable Materials

    Directory of Open Access Journals (Sweden)

    Carl Schaschke

    2014-11-01

    Full Text Available This Special Issue “Biodegradable Materials” features research and review papers concerning recent advances on the development, synthesis, testing and characterisation of biomaterials. These biomaterials, derived from natural and renewable sources, offer a potential alternative to existing non-biodegradable materials with application to the food and biomedical industries amongst many others. In this Special Issue, the work is expanded to include the combined use of fillers that can enhance the properties of biomaterials prepared as films. The future application of these biomaterials could have an impact not only at the economic level, but also for the improvement of the environment.

  5. Self-expanding metal stents in malignant esophageal obstruction: a comparison between two stent types.

    Science.gov (United States)

    Schmassmann, A; Meyenberger, C; Knuchel, J; Binek, J; Lammer, F; Kleiner, B; Hürlimann, S; Inauen, W; Hammer, B; Scheurer, U; Halter, F

    1997-03-01

    Self-expanding metal stents are a promising alternative in the palliation of malignant esophageal obstruction, but the relative value of different stent types is not well established. During a 3-year enrollment period in four different centers, 82 consecutive patients with malignant dysphagia without tumor recurrence after surgery or esophagorespiratory fistulas received either an uncovered Wallstent (44 patients) or a knitted nitinol stent (38 patients). Age (median: 79 yr), sex (F:M = 33:67), dysphagia score (median: 3), Karnofsky score (median: 53), body mass index (median: 19), type of pretreatment, tumor stage, stricture length (median: 5.4 cm), and stricture location were comparable in both stent groups. After stent placement, median dysphagia score improved markedly in both groups by two points. Procedure-related mortality (16 vs 0%; p < 0.01), early complication rate (32 vs 8%; p < 0.01), and severe persistent pain after stent placement (23 vs 0%; p < 0.002) were higher in the Wallstent compared with the knitted nitinol stent group. In contrast, stent dysfunction (7 vs 32%; p < 0.005), reintervention rate (9 vs 34%; p < 0.005), and costs were lower in the Wallstent compared with the nitinol stent group. In malignant esophageal obstruction, both stents markedly improved dysphagia. Uncovered Wallstents seem to cause more early severe complications than knitted nitinol stents. In contrast, stent dysfunction, reintervention rate, and costs appear to be higher in the nitinol stent group.

  6. A new SWL titanium stent (Zebra Stent): resistance to shockwave exposure.

    Science.gov (United States)

    Buchholz, Noor N P; Cannaby, Clive; Fong, Ruby; Gray, Andrew; Andrews, Henry O; Birch, Malcolm J

    2005-06-01

    Recently, a new-concept lumen-less Teflon-coated double-J wire stent (Zebra stent) has been introduced to facilitate residual stone clearance, in particular after SWL. Its metal core expresses highly mismatched acoustic impedance. It was the aim of this study to exclude damage to the stent through shockwaves. Also, its Teflon coating should to some degree prevent encrustation, and stents removed from stone formers were examined for encrustation. Series of 2000 shockwaves of an average and a maximum energy were applied to defined areas of Zebra stents in a waterbath on a Siemens Multiline Lithotriptor. Stents were then examined for core and sheath damage by digital photography, scanning electron microscopy, and microradiography. In addition, two Zebra stents and one conventional double-J stent from two stone formers were assessed in the same way for damage and encrustation. There was no damage whatsoever to either of the stents. Whereas there was considerable encrustation on the conventional double-J stent, there was none on the Zebra stents after 4 and 5 weeks in situ. Zebra stents resist shockwaves to a maximum number and energy sufficiently to be applied safely under SWL. Whether they resist encrustation to a higher degree in the short term than conventional stents remains to be established.

  7. MR Angiography of Peripheral Arterial Stents: In Vitro Evaluation of 22 Different Stent Types

    Directory of Open Access Journals (Sweden)

    Matthias C. Burg

    2011-01-01

    Full Text Available Purpose. To evaluate stent lumen visibility of a large sample of different peripheral arterial (iliac, renal, carotid stents using magnetic resonance angiography in vitro. Materials and Methods. 21 different stents and one stentgraft (10 nitinol, 7 316L, 2 tantalum, 1 cobalt superalloy, 1 PET + cobalt superalloy, and 1 platinum alloy were examined in a vessel phantom (vessel diameters ranging from 5 to 13 mm filled with a solution of Gd-DTPA. Stents were imaged at 1.5 Tesla using a T1-weighted 3D spoiled gradient-echo sequence. Image analysis was performed measuring three categories: Signal intensity in the stent lumen, lumen visibility of the stented lumen, and homogeneity of the stented lumen. The results were classified using a 3-point scale (good, intermediate, and poor results. Results. 7 stents showed good MR lumen visibility (4x nitinol, 2x tantalum, and 1x cobalt superalloy. 9 stents showed intermediate results (5x nitinol, 2x 316L, 1x PET + cobalt superalloy, and 1x platinum alloy and 6 stents showed poor results (1x nitinol, and 5x 316L. Conclusion. Stent lumen visibility varies depending on the stent material and type. Some products show good lumen visibility which may allow the detection of stenoses inside the lumen, while other products cause artifacts which prevent reliable evaluation of the stent lumen with this technique.

  8. Remote discovery of an asymptomatic bowel perforation by a mid-urethral sling.

    Science.gov (United States)

    Elliott, Jason E; Maslow, Ken D

    2012-02-01

    Bowel perforation is a rare complication of mid-urethral sling procedures and is usually reported shortly after the surgery. We report a remotely discovered asymptomatic bowel injury found at the time of subsequent surgery. The patient with a history of several prior pelvic surgeries underwent an uneventful retropubic mid-urethral sling placement. Five years later, during an abdominal sacrocolpopexy procedure, mesh from the mid-urethral sling was found perforating the wall of the cecum and fixating it to the right pelvic sidewall. Cecal wedge resection was performed to excise the sling mesh. Asymptomatic bowel perforation by mid-urethral sling mesh has not been previously reported. Pelvic and abdominal surgeons should be aware of the possibility of finding this injury in patients with prior sling surgeries.

  9. Primary Clear Cell Adenocarcinoma of a Urethral Diverticulum Treated with Multidisciplinary Robotic Anterior Pelvic Exenteration

    Directory of Open Access Journals (Sweden)

    Dane Scantling

    2013-01-01

    Full Text Available Primary urethral carcinoma is extremely rare and is marked by a variety of clinical symptoms. Primary carcinoma of a urethral diverticulum is still rarer and clear cell adenocarcinoma of the urethra is particularly uncommon (Swartz et al., 2006. Such infrequency has led to inadequate management guidance in the literature for a disease that is often late in presentation and carries substantial morbidity and mortality. This treatable but grave disease deserves definitive curative treatment. We present the first published instance in which it was treated with robotic anterior exenteration. In our case, a 47-year-old female was referred to the urology service for investigation of recurring urinary tract infections. During the workup, the patient was found to have an advanced clear cell urethral adenocarcinoma originating in a urethral diverticulum. We discuss the natural history of this condition, its consequences, and the first instance of its treatment using robotic anterior pelvic exenteration.

  10. Urethral pressure reflectometry before and after tension-free vaginal tape

    DEFF Research Database (Denmark)

    Saaby, Marie-Louise; Klarskov, Niels; Lose, Gunnar

    2012-01-01

    Urethral pressure reflectometry (UPR) is a new method for measuring pressure and cross-sectional area in the urethra. Our aim was to investigate if the UPR parameters at rest and during squeeze were unchanged after TVT....

  11. Reasons for the weak correlation between prostate volume and urethral resistance parameters in patients with prostatism

    NARCIS (Netherlands)

    R. Kranse (Ries); R. van Mastrigt (Ron); F.H. Schröder (Fritz); J.L.H.R. Bosch (Ruud)

    1995-01-01

    textabstractIn an attempt to increase our understanding of the clinical syndrome of benign prostatic hyperplasia (BPH) an analysis was made of the association between prostate volume as measured by transrectal ultrasound and several reported urodynamically determined urethral resis

  12. Opportunities and challenges for the biodegradable magnesium alloys as next-generation biomaterials.

    Science.gov (United States)

    Ding, Wenjiang

    2016-06-01

    In recent years, biodegradable magnesium alloys emerge as a new class of biomaterials for tissue engineering and medical devices. Deploying biodegradable magnesium-based materials not only avoids a second surgical intervention for implant removal but also circumvents the long-term foreign body effect of permanent implants. However, these materials are often subjected to an uncontrolled and fast degradation, acute toxic responses and rapid structural failure presumably due to a localized, too rapid corrosion process. The patented Mg-Nd-Zn-based alloys (JiaoDa BioMg [JDBM]) have been developed in Shanghai Jiao Tong University in recent years. The alloy series exhibit lower biodegradation rate and homogeneous nanophasic degradation patterns as compared with other biodegradable Mg alloys. The in vitro cytotoxicity tests using various types of cells indicate excellent biocompatibility of JDBM. Finally, bone implants using JDBM-1 alloy and cardiovascular stents using JDBM-2 alloy have been successfully fabricated and in vivo long-term assessment via implantation in animal model have been performed. The results confirmed the reduced degradation rate in vivo, excellent tissue compatibility and long-term structural and mechanical durability. Thus, this novel Mg-alloy series with highly uniform nanophasic biodegradation represent a major breakthrough in the field and a promising candidate for manufacturing the next generation biodegradable implants.

  13. Recent advances in biodegradable metals for medical sutures: a critical review.

    Science.gov (United States)

    Seitz, Jan-Marten; Durisin, Martin; Goldman, Jeremy; Drelich, Jaroslaw W

    2015-09-16

    Sutures that biodegrade and dissolve over a period of several weeks are in great demand to stitch wounds and surgical incisions. These new materials are receiving increased acceptance across surgical procedures whenever permanent sutures and long-term care are not needed. Unfortunately, both inflammatory responses and adverse local tissue reactions in the close-to-stitching environment are often reported for biodegradable polymeric sutures currently used by the medical community. While bioabsorbable metals are predominantly investigated and tested for vascular stent or osteosynthesis applications, they also appear to possess adequate bio-compatibility, mechanical properties, and corrosion stability to replace biodegradable polymeric sutures. In this Review, biodegradable alloys made of iron, magnesium, and zinc are critically evaluated as potential materials for the manufacturing of soft and hard tissue sutures. In the case of soft tissue closing and stitching, these metals have to compete against currently available degradable polymers. In the case of hard tissue closing and stitching, biodegradable sternal wires could replace the permanent sutures made of stainless steel or titanium alloys. This Review discusses the specific materials and degradation properties required by all suture materials, summarizes current suture testing protocols and provides a well-grounded direction for the potential future development of biodegradable metal based sutures.

  14. Palliative Surgery for Rare Cases of Anterior Urethral Metastasis in Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Enrique Gómez Gómez

    2014-01-01

    Full Text Available Penis metastasis from prostate cancer is very rare, and its management varies from case to case as there are very few cases reported in the literature. We describe a patient with prostate cancer treated with radiotherapy and androgen deprivation therapy who presented with urethral bleeding as a symptom of anterior urethral metastasis during followup. We propose a way to manage this and review the literature.

  15. Palliative Surgery for Rare Cases of Anterior Urethral Metastasis in Prostate Cancer

    Science.gov (United States)

    Gómez Gómez, Enrique; Carrasco Aznar, Jose Carlos; Moreno Rodríguez, Maria del Mar; Valero Rosa, José; Requena Tapia, Maria José

    2014-01-01

    Penis metastasis from prostate cancer is very rare, and its management varies from case to case as there are very few cases reported in the literature. We describe a patient with prostate cancer treated with radiotherapy and androgen deprivation therapy who presented with urethral bleeding as a symptom of anterior urethral metastasis during followup. We propose a way to manage this and review the literature. PMID:25161796

  16. Leiomioma uretral durante a gravidez: relato de caso Urethral leiomyoma during pregnancy: a case report

    Directory of Open Access Journals (Sweden)

    Arlon Breno Figueiredo Nunes da Silveira

    2012-12-01

    Full Text Available The authors report a case of urethral leiomyoma diagnosed during pregnancy, which was conservatively treated up to the 38th week, when the pregnancy was interrupted. Thirty days after delivery, exeresis of the lesion was performed from the upper border of the urethral meatus and sutured with interrupted delayed-absorbable suture. The patient evolved favorably and presented no lesion recurrence during three months of follow up.

  17. A Study Of The Results Of "Urethral Advancement And Glanuloplasty" (UAGP) In Repairing Anterior Hypospadias

    OpenAIRE

    2003-01-01

    Background: In this study, the results of "Urethral Advancement & Glanuloplasty" in repairing anterior hypospadias were considered. Hypospadias is a common urethral anomaly in boys. More than 65 percent of hypospadias cases are anterior (glanular, coronal and distal penil shaft). More than two hundreds original techniques have been applied to correct hypospadias. Each of these techniques has some complications. The most common complications of hypospadias repairing a...

  18. Phthalates biodegradation in the environment.

    Science.gov (United States)

    Liang, Da-Wei; Zhang, Tong; Fang, Herbert H P; He, Jianzhong

    2008-08-01

    Phthalates are synthesized in massive amounts to produce various plastics and have become widespread in environments following their release as a result of extensive usage and production. This has been of an environmental concern because phthalates are hepatotoxic, teratogenic, and carcinogenic by nature. Numerous studies indicated that phthalates can be degraded by bacteria and fungi under aerobic, anoxic, and anaerobic conditions. This paper gives a review on the biodegradation of phthalates and includes the following aspects: (1) the relationship between the chemical structure of phthalates and their biodegradability, (2) the biodegradation of phthalates by pure/mixed cultures, (3) the biodegradation of phthalates under various environments, and (4) the biodegradation pathways of phthalates.

  19. Flow disturbances in stent-related coronary evaginations

    DEFF Research Database (Denmark)

    Radu, Maria D; Pfenniger, Aloïs; Räber, Lorenz

    2014-01-01

    Aims: Angiographic ectasias and aneurysms in stented segments have been associated with late stent thrombosis. Using optical coherence tomography (OCT), some stented segments show coronary evaginations reminiscent of ectasias. The purpose of this study was to explore, using computational fluid...

  20. Acute stent thrombosis after bifurcation stenting with the crush technique visualized with 64-slice computed tomography

    DEFF Research Database (Denmark)

    Kristensen, T.S.; Engstrom, T.; Kofoed, Klaus Fuglsang

    2008-01-01

    Acute stent thrombosis remains a potential complication after stent implantation. With the introduction of electrocardiographic gated multidetector row computed tomography (MDCT), a new nonnvasive imaging modality has become available that may contribute to the detection of complications after...

  1. Evaluation of a novel stent technology: the Genous EPC capturing stent

    NARCIS (Netherlands)

    M. Klomp

    2012-01-01

    Tegenwoordig gebruiken ziekenhuizen een nieuwe stent bij dotterbehandelingen van kransslagadervernauwingen. Deze Genous-stent heeft een laag met antistoffen waardoor het behandelde bloedvat snel bedekt raakt met lichaamseigen cellen. Zo wordt tegengegaan dat er opnieuw een vernauwing optreedt of dat

  2. Newest-generation drug-eluting and bare-metal stents combined with prasugrel-based antiplatelet therapy in large coronary arteries

    DEFF Research Database (Denmark)

    Jeger, Raban; Pfisterer, Matthias; Alber, Hannes

    2012-01-01

    In the BAsel Stent Kosten Effektivitäts Trial PROspective Validation Examination (BASKET-PROVE), drug-eluting stents (DESs) had similar 2-year rates of death and myocardial infarction but lower rates of target vessel revascularization and major adverse cardiac events compared with bare-metal sten...... (BMSs). However, comparative clinical effects of newest-generation DES with biodegradable polymers vs second-generation DES or newest-generation BMS with biocompatible coatings, all combined with a prasugrel-based antiplatelet therapy, on 2-year outcomes are not known....

  3. Traumatic Posterior Urethral Fistula to the Hip Joint Following Gunshot Injury: A Case Report

    Directory of Open Access Journals (Sweden)

    Mohammad Ghasemi-Rad

    2010-05-01

    Full Text Available Introduction: Fistula of the Urinary system to the hip joint is a rare complication. We report a case of delayed posterior urethral fistula to the hip joint following penetrating gunshot wound injury."nCase Presentation: A 37-year-old man was shot with firearm to the superior part of the right pelvis. He underwent delayed reconstruction surgery for urethral rupture. After 10 months of initial injury, he presented with inability to urinate, and history of progressive pain in the right hip joint accompanied by low-grade fever, which started two months after the initial injury. In retrograde urethrography and antegrade cystography, a 5 cm-long stricture and a fistula tract to the right hip joint were detected. Hip x-ray showed evidence of acetabular cavity and femoral head destruction diagnostic of complicated septic arthritis. The patient subsequently underwent reconstructive surgery for the urethral stricture and urethral fistula via a transperineal approach followed by total hip arthroplasty."nConclusion: Hip joint contamination with urine following urethro-acetabular fistula may lead to severe and disabling complications such as septic arthritis. We recommend that every clinician should have these fistulas in mind as a complication of penetrating urethral injury; every attempt should be made for their early diagnosis and prompt treatment should be performed to prevent further complications."nKeywords: Urethral Fistula, Hip Joint, Gunshot Injury, Urethro-Acetabular Fistula, Trauma    

  4. Management of the stricture of fossa navicularis and pendulous urethral strictures

    Science.gov (United States)

    Singh, Shrawan K.; Agrawal, Santosh K.; Mavuduru, Ravimohan S.

    2011-01-01

    Objective: Management of distal anterior urethral stricture is a common problem faced by practicing urologists. Literature on urethral stricture mainly pertains to bulbar urethral stricture and pelvic fracture urethral distraction defect. The present article aims to review the management of the strictures of fossa navicularis and pendulous urethra. Materials and Methods: The literature in English language was searched from the National Library of Medicine database, using the appropriate key words for the period 1985-2010. Out of 475 articles, 115 were selected for the review based on their relevance to the topic. Results: Etiology of stricture is shifting from infective to inflammatory and iatrogenic causes. Stricture of fossa navicularis is most often caused by lichen sclerosus et atrophicus and instrumentation. Direct visual internal urethrotomy is limited to selected cases in the management of pendulous urethral stricture. With experience and identification of various prognostic factors, conservative management by dilatation and internal urethrotomy is being replaced by various reconstructive procedures, using skin flaps and grafts with high success rates. Single-stage urethroplasty is preferred over the 2-stage procedure as the latter disfigures the penis and poses sexual problems temporarily. Conclusions: Flaps or grafts are useful for single-stage reconstruction of fossa navicularis and pendulous urethral strictures. The buccal and lingual mucosa serves as a preferred resource material for providing the inner lining of the urethra. Off-the-shelf materials, such as acellular collagen matrix, are promising. PMID:22022062

  5. Grey water biodegradability

    NARCIS (Netherlands)

    Abu Ghunmi, L.; Zeeman, G.; Fayyad, M.; Lier, van J.B.

    2011-01-01

    Knowing the biodegradability characteristics of grey water constituents is imperative for a proper design and operation of a biological treatment system of grey water. This study characterizes the different COD fractions of dormitory grey water and investigates the effect of applying different condi

  6. Biodegradable Materials for Nonwovens

    Science.gov (United States)

    Demand for nonwovens is increasing globally, particularly in the disposable products area. As the consumption of nonwoven products with short life increases, the burden on waste disposal also rises. In this context, biodegradable nonwovens become more important today and for the future. Several new ...

  7. Grey water biodegradability

    NARCIS (Netherlands)

    Abu Ghunmi, L.; Zeeman, G.; Fayyad, M.; Van Lier, J.B.

    2010-01-01

    Knowing the biodegradability characteristics of grey water constituents is imperative for a proper design and operation of a biological treatment system of grey water. This study characterizes the different COD fractions of dormitory grey water and investigates the effect of applying different condi

  8. Influence of strut cross-section of stents on local hemodynamics in stented arteries

    Science.gov (United States)

    Jiang, Yongfei; Zhang, Jun; Zhao, Wanhua

    2016-05-01

    Stenting is a very effective treatment for stenotic vascular diseases, but vascular geometries altered by stent implantation may lead to flow disturbances which play an important role in the initiation and progression of restenosis, especially in the near wall in stented arterial regions. So stent designs have become one of the indispensable factors needed to be considered for reducing the flow disturbances. In this paper, the structural designs of strut cross-section are considered as an aspect of stent designs to be studied in details. Six virtual stents with different strut cross-section are designed for deployments in the same ideal arterial model. Computational fluid dynamics (CFD) methods are performed to study how the shape and the aspect ratio (AR) of strut cross-section modified the local hemodynamics in the stented segments. The results indicate that stents with different strut cross-sections have different influence on the hemodynamics. Stents with streamlined cross-sectional struts for circular arc or elliptical arc can significantly enhance wall shear stress (WSS) in the stented segments, and reduce the flow disturbances around stent struts. The performances of stents with streamlined cross-sectional struts are better than that of stents with non-streamlined cross-sectional struts for rectangle. The results also show that stents with a larger AR cross-section are more conductive to improve the blood flow. The present study provides an understanding of the flow physics in the vicinity of stent struts and indicates that the shape and AR of strut cross-section ought to be considered as important factors to minimize flow disturbance in stent designs.

  9. Carotid artery stent continued expansion days after deployment, without post stent deployment angioplasty

    Directory of Open Access Journals (Sweden)

    Umair Qazi

    2015-10-01

    Full Text Available This is a carotid artery stent (CAS case report, which avoids post-stent deployment angioplasty (Post-SDA, with duplex confirmed continued stent expansion at 1, 3 and 30-day post deployment. This report confirms that self-expanding nitinol stents in the carotid artery may not require Post-SDA. We believe CAS can be performed without Post-SDA, which helps reduce the occurrence of intraoperative hemodynamic depression.

  10. Safety, efficacy and costs associated with direct coronary stenting compared with stenting after predilatation

    Science.gov (United States)

    IJsselmuiden, A.; Serruys, P.W.; Tangelder, G.J.; Slagboom, T.; van der Wieken, R.; Kiemeneij, F.; Laarman, G.J.

    2004-01-01

    Objectives Comparison of the in-hospital success rates, procedural costs and short-term clinical outcomes of direct stenting versus stenting after balloon predilatation. Methods Altogether, 400 patients with angina pectoris and/or myocardial ischaemia due to coronary stenoses in a single native vessel were randomised to either direct stenting or stenting after predilatation. Baseline characteristics were evenly distributed between the two groups. Results Procedural success rates were similar (96.0% direct stenting group vs. 94.5% predilatation) as well as final successful stent implantation (98.3 vs. 97.8%), while the primary success rate of direct stenting alone was 88.3%, p=0.01. In multivariate analysis, angiographic lesion calcification was an independent predictor of unsuccessful direct stenting (odds ratio 7.1, 95% confidence interval 2.8-18.2, p0.15 μg/l, used as a measure of distal embolisation, were similar in both groups (17.8 vs. 17.1%). Rates of major adverse cardiac events at 30 days were 4.5% in the direct stenting group versus 5.5% in the predilated group (ns). Direct stenting was associated with savings in fluoroscopy time, and angiographic contrast agent use, and a reduction in utilisation of angioplasty balloons (0.4 vs. 1.17 balloons per patient, p<0.001). Mean per patient procedural costs associated with direct stenting versus predilatation were €2545±914 versus €2763±842 (p=0.01), despite the implantation of more stents in the directly stented group. Conclusion Compared with a strategy of stenting preceded by balloon predilatation, direct stenting was equally safe and effective, with similar in-hospital and 30-day clinical outcomes, and modest procedural cost-savings. A calcified lesion predicted unsuccessful direct stenting. PMID:25696356

  11. Intermittent self-dilatation for urethral stricture disease in males.

    Science.gov (United States)

    Jackson, Matthew J; Veeratterapillay, Rajan; Harding, Chris K; Dorkin, Trevor J

    2014-12-19

    Intermittent urethral self-dilatation is sometimes recommended to reduce the risk of recurrent urethral stricture. There is no consensus as to whether it is a clinically effective or cost-effective intervention in the management of this disease. The purpose of this review is to evaluate the clinical effectiveness and cost-effectiveness of intermittent self-dilatation after urethral stricture surgery in males compared to no intervention. We also compared different programmes of, and devices for, intermittent self-dilatation. . We searched the Cochrane Incontinence Group Specialised Register (searched 7 May 2014), CENTRAL (2014, Issue 4), MEDLINE (1 January 1946 to Week 3 April 2014), PREMEDLINE (covering 29 April 2014), EMBASE (1 January 1947 to Week 17 2014), CINAHL (31 December 1981 to 30 April 2014) OpenGrey (searched 6 May 2014), ClinicalTrials.gov (6 May 2014), WHO International Clinical Trials Registry Platform (6 May 2014), Current Controlled Trials (6 May 2014) and the reference lists of relevant articles. Randomised and quasi-randomised trials where one arm was a programme of intermittent self-dilatation for urethral stricture were identified. Studies were excluded if they were not randomised or quasi-randomised trials, or if they pertained to clean intermittent self-catheterisation for bladder emptying. Two authors screened the records for relevance and methodological quality. Data extraction was performed according to predetermined criteria using data extraction forms. Analyses were carried out in Cochrane Review Manager (RevMan 5). The primary outcomes were patient-reported symptoms and health-related quality of life, and risk of recurrence; secondary outcomes were adverse events, acceptability of the intervention to patients and cost-effectiveness. Quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Eleven trials were selected for inclusion in the review, including a total of 776

  12. Review of stents for the carotid artery.

    Science.gov (United States)

    Bosiers, M; Deloose, K; Verbist, J; Peeters, P

    2006-04-01

    The individual characteristics of a stent may make it an attractive choice in some circumstances, but render it a less desirable option in others. The applicability depends primarily on the arterial anatomy and the specific details of the lesion being treated. A careful assessment by the interventionalist is required to select the proper type of stent that is of appropriate size. Certainly, personal preferences and familiarity with a specific device may legitimately influence the decision to choose one stent over another. Finally, stent design can play a role in the selection procedure. Although carotid stents are often functionally equivalent in the clinical setting and have been used successfully to treat a wide variety of lesions, a basic knowledge of stent geometry can contribute to make up your mind in certain carotid cases.

  13. Rapid virtual stenting for intracranial aneurysms

    Science.gov (United States)

    Zhao, Liang; Chen, Danyang; Chen, Zihe; Wang, Xiangyu; Paliwal, Nikhil; Xiang, Jianping; Meng, Hui; Corso, Jason J.; Xu, Jinhui

    2016-03-01

    The rupture of Intracranial Aneurysms is the most severe form of stroke with high rates of mortality and disability. One of its primary treatments is to use stent or Flow Diverter to divert the blood flow away from the IA in a minimal invasive manner. To optimize such treatments, it is desirable to provide an automatic tool for virtual stenting before its actual implantation. In this paper, we propose a novel method, called ball-sweeping, for rapid virtual stenting. Our method sweeps a maximum inscribed sphere through the aneurysmal region of the vessel and directly generates a stent surface touching the vessel wall without needing to iteratively grow a deformable stent surface. Our resulting stent mesh has guaranteed smoothness and variable pore density to achieve an enhanced occlusion performance. Comparing to existing methods, our technique is computationally much more efficient.

  14. Esophageal stent migration leads to intestinal obstruction

    Directory of Open Access Journals (Sweden)

    Oguzhan Karatepe

    2009-07-01

    Full Text Available Background: Self-expanding metallic stents are the devices of choice in the treatment of malign or benign strictures of esophagus. Stent migration is a well-known complication of this procedure. Aims: We report a case of intestinal obstruction caused by esophageal stent migration, in which surgical intervention was used. Methods: A 65-year-old woman, who had a medical history of gastric cancer operation and esophageal stent application admitted to our emergeny department with a 48-hour history of abdominal pain, nausea and vomiting. An emergeny laparotomy was performed and the migrated stent leading to intestinal obstruction was removed. Results: The patient recovered without incident and was discharged on postoperative day 3. Conclusion: This case illustrates that esophageal stent migration has to be considered as a potential life-threatening complication.

  15. Hypersensitivity to drug-eluting stent and stent thrombosis: Kounis or not Kounis syndrome?

    Institute of Scientific and Technical Information of China (English)

    TAN Wei; CHENG Kang-lin; CHEN Qiu-xiong

    2009-01-01

    @@ With the utilization of coronary-stents, coronary remodeling and restenosis were reduced compared with balloon angioplasty alone.~1 However, the risk of restenosis is still in the range of 15% to 20%. Drug-eluting stents (DES), which could release antiproliferative pharmacological agents after deployment. were designed to inhibit the response to injury reaction after bare-metal stent (BMS) implantation.

  16. Mechanical behavior of peripheral stents and stent-vessel interaction: A computational study

    Science.gov (United States)

    Dottori, Serena; Flamini, Vittoria; Vairo, Giuseppe

    2016-05-01

    In this paper stents employed to treat peripheral artery disease are analyzed through a three-dimensional finite-element approach, based on a large-strain and large-displacement formulation. Aiming to evaluate the influence of some stent design parameters on stent mechanics and on the biomechanical interaction between stent and arterial wall, quasi-static and dynamic numerical analyses are carried out by referring to computational models of commercially and noncommercially available versions of both braided self-expandable stents and balloon-expandable stents. Addressing isolated device models, opening mechanisms and flexibility of both opened and closed stent configurations are numerically experienced. Moreover, stent deployment into a stenotic peripheral artery and possible postdilatation angioplasty (the latter for the self-expandable device only) are simulated by considering different idealized vessel geometries and accounting for the presence of a stenotic plaque. Proposed results highlight important differences in the mechanical response of the two types of stents, as well as a significant influence of the vessel shape on the stress distributions arising upon the artery-plaque system. Finally, computational results are used to assess both the stent mechanical performance and the effectiveness of the stenting treatment, allowing also to identify possible critical conditions affecting the risk of stent fracture, tissue damage, and/or pathological tissue response.

  17. Advances in drug eluting stents – focus on the Endeavor® zotarolimus stent

    Directory of Open Access Journals (Sweden)

    Jonathan Bridges

    2008-12-01

    Full Text Available Jonathan Bridges, Donald CutlipBeth Israel Deaconess Medical Center, Boston, Massachusetts, USAAbstract: Coronary artery disease remains one of the leading causes of death in the United States. Over the last 30 years, the development of coronary artery angioplasty and stenting has drastically reduced mortality during acute coronary syndromes while also reducing symptoms of chronic coronary artery disease. Unfortunately, the placement of stents in a coronary artery can be complicated by in-stent thrombosis or restenosis. In 2003–2004, a new generation of stents was introduced to the market with the goal of reducing the rate of restenosis. These stents, called drug eluting stents (DES, are coated with a pharmacological agent designed to reduce the neointimal hyperplasia associated with restenosis. Within a year, approximately 80% of all percutaneous coronary interventions performed within the US involved placement of a DES. In 2006, a controversy arose about the possibility of a statistically significant increased risk of acute stent thrombosis associated with DES especially when used for an “off label” indication. This risk was attributed to delayed endothelization. This controversy has led to a reduction in the use of DES along with longer use of dual platelet inhibition with aspirin and clopidogrel. Recently Medtronic introduced a new DES to the market called the Endeavor® stent – a zotarolimus eluting stent.Keywords: Endeavor® stent, zotarolimus stent, drug eluting stent

  18. Advanced stent coating for drug delivery and in vivo biocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yi; Wang, Wuchen; Acharya, Gayathri [University of Missouri at Kansas City, Division of Pharmaceutical Sciences, School of Pharmacy (United States); Shim, Yoon-Bo [Pusan National University, Departments of Chemistry (Korea, Republic of); Choe, Eun Sang [Pusan National University, Departments of Biological Sciences (Korea, Republic of); Lee, Chi H., E-mail: leech@umkc.edu [University of Missouri at Kansas City, Division of Pharmaceutical Sciences, School of Pharmacy (United States)

    2013-10-15

    As an effort to alleviate stent-induced cardiovascular injury including restenosis and thrombosis, advanced drug-eluting stent (ADES) with a bilayer construct composed of a top-coat made of collagen and a base-coat incorporated with N-nitrosomelatonin (NOMela)-loaded PLGA nanoparticles has been developed. NOMela is a hydrophobic prodrug of nitric oxide (NO) that is an endogenous anti-platelet compound. ADES was coated with PLGA nanoparticles via either electrophoretic deposition (EPD) technique or dip-coating technique, and their coating characteristics and efficacies were compared. The drug-loading efficacy and in vitro drug-release profiles from ADES were expressed with various variables including the additives to the collagen layer, the number of layers of the collagen top-coat, the hydrophobicity/hydrophilicity of the loaded drug, the coating technique of nanoparticles, and the concentration of coating emulsions in the EPD method. The morphological status of cross-section and surface of ADES was evaluated by laser scanning confocal microscope and scanning electronic microscope. The real-time release profiles of NO were assessed using the NO-microbiosensor. The anti-platelet activity of ADES was evaluated on the rabbit whole blood using an aggregometer. The intima formation and protein expression in aorta were examined using an in vivo rat model. Both collagen and PLGA used in ADES are biodegradable polymers that fully degrade and consequently produce less inflammation responses. NO released from ADES significantly reduced platelet aggregation in the rabbit blood as compared with those exposed to the control stents. ADES coated with a double layer consisted of collagen and PLGA and containing NOMela was less antigenic at the implanted sites and alleviating intima formation and thrombosis. An external exposure of aorta to NO elicits distinct and specific effects on mitogen-activated protein kinase (MAPK) and Ca{sup 2+}/calmodulin-dependent protein kinase II (Ca

  19. Stent implantation influence wall shear stress evolution

    Science.gov (United States)

    Bernad, S. I.; Totorean, A. F.; Bosioc, A. I.; Petre, I.; Bernad, E. S.

    2016-06-01

    Local hemodynamic factors are known affect the natural history of the restenosis critically after coronary stenting of atherosclerosis. Stent-induced flows disturbance magnitude dependent directly on the strut design. The impact of flow alterations around struts vary as the strut geometrical parameters change. Our results provide data regarding the hemodynamic parameters for the blood flow in both stenosed and stented coronary artery under physiological conditions, namely wall shear stress and pressure drop.

  20. Assessment of Coronary Stents by 64-slice Computed Tomography:In-stent Lumen Visibility and Patency

    Institute of Scientific and Technical Information of China (English)

    Ling-yan Kong; Zheng-yu Jin; Shu-yang Zhang; Zhu-hua Zhang; Yi-ning Wang; Lan Song; Xiao-na Zhang; Yun-qing Zhang

    2009-01-01

    Objective To assess lumen visibility of coronary stents by 64-slice computed tomography(CT)coronary angiography,and determine the value of 64-slice CT in non-invasive detecting of in-stent restenosis after coronary artery stent implantation.Methods Totally,60 patients(54 males,aged 57.0±12.7 years)and 105 stents were investigated by 64-slice CT at a mean interval of 20.0±16.6 months after coronary stents implantation.Axial multi-planar reconstruction images of the stents and curved-planar reconstruction images through the median of the stents were reconstructed for evaluating stent image quality on a 5-point scale(1=excellent,5=nonassessable),and stent lumen diameter was detected.Conventional coronary angiography was performed in 18 patients,and 32 stents were evaluated.Results Image quality was good to excellent on average(score 1.71±0.76).Stent image quality score was correlated to heart rate(r=0.281,P<0.01)and stent diameter(r=0.480,P<0.001).All the stents were assessable in lumen visibility with an average visible lumen diameter percentage of 60.7% ±13.6% .Visible lumen diameter percentage was correlated to heart rate(r=-0.193,P<0.05),stent diameter (r=0.403,P<0.001),and stent image quality score(r=-0.500,P<0.001).Visible lumen diameter percentage also varied depending on the stent type.In comparison with the conventional coronary angiography,4 of 6 in-stent stenoses were correctly detected.The sensitivity and specificity for the detection of in-stent stenosis were 66.7% and 84.6% ,respectively.Conclusions Using a 64-slice CT,the stent lumen is partly visible in most of the stents.And 64-slice CT may be useful in the assessment of stent patency.

  1. Palladium interstitial implant in combination with external beam radiotherapy and chemotherapy for the definitive treatment of a female urethral carcinoma

    Directory of Open Access Journals (Sweden)

    Hilary P. Bagshaw

    2015-08-01

    Full Text Available Primary urethral cancer is a rare diagnosis, especially in females. This report presents the utilization of a palladium interstitial implant and a review of the retrospective data published on the management of female urethral cancer. Excellent local control and survival has been obtained with the use of a palladium interstitial implant in combination with external beam radiotherapy and concurrent chemotherapy. This modality represents a novel and effective way to treat primary urethral cancer in females.

  2. Treatment of urethral strictures in balanitis xerotica obliterans (BXO) using circular buccal mucosal meatoplasy: Experience of 15 cases

    OpenAIRE

    2014-01-01

    Objectives: Balanitis xerotica obliterans (BXO) related strictures involving the external urethral meatus. We reviewed our result with the use of circular mucosal graft in the reconstruction of strictures. Methods: Between March 1997 and January 2012, 15 patients underwent circular buccal mucosal urethroplasy for BXO related anterior urethral strictures. Urethral catheter was removed within 2 weeks. Follow-up included patient symptoms assessment, cosmetic outcome and uroflowmetry. Results: Me...

  3. Novel stents for the prevention of restenosis.

    Science.gov (United States)

    McKenna, C J; Holmes, D R; Schwartz, R S

    1997-10-01

    Since the introduction of Interventional Cardiology in 1976, there has been rapid expansion both in its clinical application and the tools of the trade. This growth was accelerated with the introduction of the intra-coronary stent in 1987. The demonstration that stents may reduce the incidence of restenosis after percutaneous coronary revascularization has further stimulated the search for the perfect endovascular prosthesis. By creating a hybrid stent, incorporating natural coatings and local drug delivery in the design, it is hoped that the complications associated with stent thrombosis and restenosis can be eradicated. (Trends Cardiovasc Med 1997;7:245-249). © 1997, Elsevier Science Inc.

  4. Stent Fracture: Case Report and Literature Review

    OpenAIRE

    Lousinha, A; Fiarresga, A; Cardona, L.; Lopes, JP; Lopes, A.; Cacela, D; L. Sousa; Patrício, L; Bernardes, L; Cruz Ferreira, R

    2011-01-01

    Apresentamos o caso de um doente, previamente submetido a angioplastia coronária com um stent revestido com fármaco, com enfarte agudo do miocárdio (EAM) provocado por trombose tardia do stent, tendo sido detectada fractura do mesmo. Este caso vem reforçar o reconhecimento crescente da fractura como potencial mecanismo para a trombose tardia de stent, na era dos stents revestidos com fármaco. A propósito deste caso clínico, apresentamos uma revisão da liter...

  5. Stenting:84 Cases of Clinical Application

    Institute of Scientific and Technical Information of China (English)

    GUANG Yongsong

    2002-01-01

    Objective To evaluate clinical application of therapeutic stenting. Methods 84 cases were managed with stents clinically, 136 procedures of intervention in all. The cases were suffering from portal hypertension of cirrhosis, stricture of inferior vana cava, superior vana cava syndrome, post- operative esophageal stricture, narrowig of femoral, common carotid, renal, superior mesentery arteries and biliary tract, etc. Results Therapeutic stenting achieves clinical effects completely different from conventional intemal medicine and surgery. Conclusion Therapeutic stenting is clinically unique, dramatically effective, with minor risks and worthy promoting.

  6. Nitinol stent design - understanding axial buckling.

    Science.gov (United States)

    McGrath, D J; O'Brien, B; Bruzzi, M; McHugh, P E

    2014-12-01

    Nitinol׳s superelastic properties permit self-expanding stents to be crimped without plastic deformation, but its nonlinear properties can contribute towards stent buckling. This study investigates the axial buckling of a prototype tracheobronchial nitinol stent design during crimping, with the objective of eliminating buckling from the design. To capture the stent buckling mechanism a computational model of a radial force test is simulated, where small geometric defects are introduced to remove symmetry and allow buckling to occur. With the buckling mechanism ascertained, a sensitivity study is carried out to examine the effect that the transitional plateau region of the nitinol loading curve has on stent stability. Results of this analysis are then used to redesign the stent and remove buckling. It is found that the transitional plateau region can have a significant effect on the stability of a stent during crimping, and by reducing the amount of transitional material within the stent hinges during loading the stability of a nitinol stent can be increased.

  7. Uerthral Obstruction By a Foregin Body:An Unusal Presentation of Ano-Rectal Malformation With Recto-Urethral Fistuala

    Directory of Open Access Journals (Sweden)

    Nasib C.Digray,D.R.Thapa,H.L.Gowamy,Ratanakar Sharma

    2000-04-01

    Full Text Available A 16 months old male child with features of acute urinary and intestinal obstruction due toa vegetative foreign body (FB impacted in the anterior urethra is presented. The patient hadan untreated intermediate ano-rectal malformation (ARM with wide recto-urethral fistula(RUF. Multiple other congenital anomalies were, also, seen in this patient. The foreignbody was removed by an external urethral meatotomy, relieving recto-urethral obstruction.However, the child died of septicaemia 6 hours post-operativerly. To best ofOUt knowledge,this is the first case of ARM, presenting with urethral obstruction due to a foreign body.

  8. Aorta Segmentation for Stent Simulation

    CERN Document Server

    Egger, Jan; Setser, Randolph; Renapuraar, Rahul; Biermann, Christina; O'Donnell, Thomas

    2011-01-01

    Simulation of arterial stenting procedures prior to intervention allows for appropriate device selection as well as highlights potential complications. To this end, we present a framework for facilitating virtual aortic stenting from a contrast computer tomography (CT) scan. More specifically, we present a method for both lumen and outer wall segmentation that may be employed in determining both the appropriateness of intervention as well as the selection and localization of the device. The more challenging recovery of the outer wall is based on a novel minimal closure tracking algorithm. Our aortic segmentation method has been validated on over 3000 multiplanar reformatting (MPR) planes from 50 CT angiography data sets yielding a Dice Similarity Coefficient (DSC) of 90.67%.

  9. Intravascular Stenting in Microvascular Anastomoses

    DEFF Research Database (Denmark)

    Assersen, Kristine; Sørensen, Jens

    2015-01-01

    Background The effect of intravascular stenting (IVaS) on microvascular anastomoses has given adverse results. For experienced microsurgeons the benefit of IVaS is doubtful. We have investigated the potential benefit of the IVaS technique for two groups of inexperienced microsurgeons with different...... surgical levels of experience (medical students and young residents). Experienced microsurgeons acted as a control group. Materials and Methods In an experimental crossover study, 139 microsurgical anastomoses were performed on the femoral artery in 70 rats by 10 surgeons. On one side of the rat, the IVaS...... spent on the anastomosis. Results No significant difference in patency rates was seen between the stenting and conventional technique in all three groups. The experienced microsurgeons had 100% patency rate with both techniques. The medical students had 20/28 in the IVaS and 19/28 conventional group...

  10. Late stent malapposition and marked positive vessel remodeling after sirolimus-eluting coronary stent implantation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Feng; QIAN Ju-ying; GE Jun-bo

    2006-01-01

    @@ It has been reported that positive remodeling, regression of neointimal hyperplasia, and late malapposition are associated with brachytherapy, one of the approaches to prevent first-time and recurrent in-stent restenosis.1,2 Recently, some drug-eluting stents have been demonstrated to dramatically reduce restenosis rates.3,4 Despite these promising results, these drug-eluting stents may have the same potential risks as brachytherapy, with some similarities between the 2 technologies in anti- proliferative effects on vascular smooth muscle cells and endothelial cells. We reported a case of late stent malapposition and marked positive vessel remodeling after sirolimus-eluting coronary stent implantation.

  11. Delayed cerebral infarction due to stent folding deformation following carotid artery stenting

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Kwon Duk; Lee, Kyung Yul; Suh, Sang Hyun [Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, Byung Moon [Dept. of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2014-12-15

    We report a case of delayed cerebral infarction due to stent longitudinal folding deformation following carotid artery stenting using a self-expandable stent with an open-cell design. The stented segment of the left common carotid artery was divided into two different lumens by this folding deformation, and the separated lumens became restricted with in-stent thrombosis. Although no established method of managing this rare complication exists, a conservative approach was taken with administration of anticoagulant and dual antiplatelet therapy. No neurological symptoms were observed during several months of clinical follow-up after discharge.

  12. Peri-stent contrast staining, major evaginations and severe malapposition after biolimus-eluting stent implantation

    DEFF Research Database (Denmark)

    Antonsen, Lisbeth; Thayssen, Per; Jensen, Lisette Okkels

    2014-01-01

    Peri-stent contrast staining and late acquired malapposition represent pathological vessel wall healing patterns following percutaneous coronary intervention with stent implantation. Earlier studies have described these abnormal vessel wall responses commonly present after implantation of first......-generation drug-eluting stents. These coronary vascular changes can cause flow disturbance and thereby dispose for later thrombotic events. This case report, based on coronary optical frequency domain imaging, describes peri-stent contrast staining, major evaginations and severe malapposition occurring 18months...... after third-generation biolimus-eluting stent implantation....

  13. Biodegradable Polymers Influence the Effect of Atorvastatin on Human Coronary Artery Cells.

    Science.gov (United States)

    Strohbach, Anne; Begunk, Robert; Petersen, Svea; Felix, Stephan B; Sternberg, Katrin; Busch, Raila

    2016-01-22

    Drug-eluting stents (DES) have reduced in-stent-restenosis drastically. Yet, the stent surface material directly interacts with cascades of biological processes leading to an activation of cellular defense mechanisms. To prevent adverse clinical implications, to date almost every patient with a coronary artery disease is treated with statins. Besides their clinical benefit, statins exert a number of pleiotropic effects on endothelial cells (ECs). Since maintenance of EC function and reduction of uncontrolled smooth muscle cell (SMC) proliferation represents a challenge for new generation DES, we investigated the effect of atorvastatin (ATOR) on human coronary artery cells grown on biodegradable polymers. Our results show a cell type-dependent effect of ATOR on ECs and SMCs. We observed polymer-dependent changes in IC50 values and an altered ATOR-uptake leading to an attenuation of statin-mediated effects on SMC growth. We conclude that the selected biodegradable polymers negatively influence the anti-proliferative effect of ATOR on SMCs. Hence, the process of developing new polymers for DES coating should involve the characterization of material-related changes in mechanisms of drug actions.

  14. Biodegradable Polymers Influence the Effect of Atorvastatin on Human Coronary Artery Cells

    Directory of Open Access Journals (Sweden)

    Anne Strohbach

    2016-01-01

    Full Text Available Drug-eluting stents (DES have reduced in-stent-restenosis drastically. Yet, the stent surface material directly interacts with cascades of biological processes leading to an activation of cellular defense mechanisms. To prevent adverse clinical implications, to date almost every patient with a coronary artery disease is treated with statins. Besides their clinical benefit, statins exert a number of pleiotropic effects on endothelial cells (ECs. Since maintenance of EC function and reduction of uncontrolled smooth muscle cell (SMC proliferation represents a challenge for new generation DES, we investigated the effect of atorvastatin (ATOR on human coronary artery cells grown on biodegradable polymers. Our results show a cell type-dependent effect of ATOR on ECs and SMCs. We observed polymer-dependent changes in IC50 values and an altered ATOR-uptake leading to an attenuation of statin-mediated effects on SMC growth. We conclude that the selected biodegradable polymers negatively influence the anti-proliferative effect of ATOR on SMCs. Hence, the process of developing new polymers for DES coating should involve the characterization of material-related changes in mechanisms of drug actions.

  15. Reinnervation of Urethral and Anal Sphincters With Femoral Motor Nerve to Pudendal Nerve Transfer

    Science.gov (United States)

    Ruggieri, Michael R.; Braverman, Alan S.; Bernal, Raymond M.; Lamarre, Neil S.; Brown, Justin M.; Barbe, Mary F.

    2012-01-01

    Aims Lower motor neuron damage to sacral roots or nerves can result in incontinence and a flaccid urinary bladder. We showed bladder reinnervation after transfer of coccygeal to sacral ventral roots, and genitofemoral nerves (L1, 2 origin) to pelvic nerves. This study assesses the feasibility of urethral and anal sphincter reinnervation using transfer of motor branches of the femoral nerve (L2–4 origin) to pudendal nerves (S1, 2 origin) that innervate the urethral and anal sphincters in a canine model. Methods Sacral ventral roots were selected by their ability to stimulate bladder, urethral sphincter, and anal sphincter contraction and transected. Bilaterally, branches of the femoral nerve, specifically, nervus saphenous pars muscularis [Evans HE. Miller’s anatomy of the dog. Philadelphia: W.B. Saunders; 1993], were transferred and end-to-end anastomosed to transected pudendal nerve branches in the perineum, then enclosed in unipolar nerve cuff electrodes with leads to implanted RF micro-stimulators. Results Nerve stimulation induced increased anal and urethral sphincter pressures in five of six transferred nerves. Retrograde neurotracing from the bladder, urethral sphincter, and anal sphincter using fluorogold, fast blue, and fluororuby, demonstrated urethral and anal sphincter labeled neurons in L2–4 cord segments (but not S1–3) in nerve transfer canines, consistent with rein-nervation by the transferred femoral nerve motor branches. Controls had labeled neurons only in S1–3 segments. Postmortem DiI and DiO labeling confirmed axonal regrowth across the nerve repair site. Conclusions These results show spinal cord reinnervation of urethral and anal sphincter targets after sacral ventral root transection and femoral nerve transfer (NT) to the denervated pudendal nerve. These surgical procedures may allow patients to regain continence. PMID:21953679

  16. Balloon Cell Urethral Melanoma: Differential Diagnosis and Management

    Directory of Open Access Journals (Sweden)

    M. McComiskey

    2015-01-01

    Full Text Available Introduction. Primary malignant melanoma of the urethra is a rare tumour (0.2% of all melanomas that most commonly affects the meatus and distal urethra and is three times more common in women than men. Case. A 76-year-old lady presented with vaginal pain and discharge. On examination, a 4 cm mass was noted in the vagina and biopsy confirmed melanoma of a balloon type. Preoperative CT showed no distant metastases and an MRI scan of the pelvis demonstrated no associated lymphadenopathy. She underwent anterior exenterative surgery and vaginectomy also. Histology confirmed a urethral nodular malignant melanoma. Discussion. First-line treatment of melanoma is often surgical. Adjuvant treatment including chemotherapy, radiotherapy, or immunotherapy has also been reported. Even with aggressive management, malignant melanoma of the urogenital tract generally has a poor prognosis. Recurrence rates are high and the mean period between diagnosis and recurrence is 12.5 months. A 5-year survival rate of less than 20% has been reported in balloon cell melanomas along with nearly 20% developing local recurrence. Conclusion. To the best of our knowledge, this case is the first report of balloon cell melanoma arising in the urethra. The presentation and surgical management has been described and a literature review provided.

  17. Posterior urethral valves: relationship between vesicoureteral reflux and renal function.

    Science.gov (United States)

    Cozzi, Denis A; Morgante, Debora; Frediani, Simone; Iaconelli, Romina; Ceccanti, Silvia; Mele, Ermelinda; Cozzi, Francesco

    2011-05-01

    To investigate the relationship between renal function and vesicoureteral reflux before and after valve ablation in patients with posterior urethral valves. In these patients, back pressure may not be the only cause of renal damage. We conducted a retrospective review of 37 patients with valves consecutively treated between 1970 and 2002. Data were available for 31 patients, 19 of whom presented reflux at presentation. Grade of reflux was ascertained by voiding cystourethrography. Overall renal function was measured by serum creatinine, and split renal function was estimated by dimercaptosuccinic acid scan available for all patients but two. Before relief of obstruction, there was no correlation between split renal function and grade of reflux into 25 kidneys of the 17 patients (r = -.13; 95% CI, -.50 to .27; P = .51). High-grade reflux (grade IV-V) affected 6 of the 11 renal units, with split renal function >40% vs 11 of the 14 units with split renal function 40% vs 4 of the 14 units with split renal function <40% (P = .0005). The good renal function of more than half of the renal units with high-grade reflux at presentation, and the persistence of reflux mainly in nonfunctioning or poorly functioning kidneys after valve ablation, support the concept that in some patients with valves, reflux and renal damage are associated anomalies. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Characteristics of gonococci isolated from men with urethritis in Dubai.

    Science.gov (United States)

    Al-Hattawi, K; Ison, C A

    1996-02-01

    Neisseria gonorrhoeae were collected from men attending out-patient clinics in Dubai. The susceptibility to a range of therapeutic antibiotics and their auxotype and serotype was determined. The plasmid content of all penicillinase-producing strains was also analysed. Thirty-six strains of N. gonorrhoeae were isolated from specimens collected from 79 patients over a 24-day period. Of the 36 isolates, 9(25%) were penicillinase-producing N. gonorrhoeae (PPNG) and 15 (42%) were chromosomally resistant N. gonorrhoeae (CMRNG). CMRNG exhibited higher levels of resistance to cefuroxime, chloramphenicol, tetracycline and erythromycin than PPNG. All isolates were susceptible to ceftriaxone and spectinomycin. Three (8%) isolates showed reduced susceptibility (MIC, > or = 0.25 mg/l) to ciprofloxacin. Six isolates of PPNG carried the 4.4 MD and three the 3.2 MD penicillinase encoding plasmid. The total gonococcal population was phenotypically diverse, with 12 serovars, 6 auxotypes and 21 A/S classes. Gonorrhoea was found to be a major cause of urethritis in Dubai and the strains exhibited high levels of resistance to penicillin.

  19. Absorbable and biodegradable polymers

    CERN Document Server

    Shalaby, Shalaby W

    2003-01-01

    INTRODUCTION NOTES: Absorbable/Biodegradable Polymers: Technology Evolution. DEVELOPMENT AND APPLICATIONOF NEW SYSTEMS: Segmented Copolyesters with Prolonged Strength Retention Profiles. Polyaxial Crystalline Fiber-Forming Copolyester. Polyethylene Glycol-Based Copolyesters. Cyanoacrylate-Based Systems as Tissue Adhesives. Chitosan-Based Systems. Hyaluronic Acid-Based Systems. DEVELOPMENTS IN PREPARATIVE, PROCESSING, AND EVALUATION METHODS: New Approaches to the Synthesis of Crystalline. Fiber-Forming Aliphatic Copolyesters. Advances in Morphological Development to Tailor the Performance of Me

  20. Safe biodegradable fluorescent particles

    Science.gov (United States)

    Martin, Sue I.; Fergenson, David P.; Srivastava, Abneesh; Bogan, Michael J.; Riot, Vincent J.; Frank, Matthias

    2010-08-24

    A human-safe fluorescence particle that can be used for fluorescence detection instruments or act as a safe simulant for mimicking the fluorescence properties of microorganisms. The particle comprises a non-biological carrier and natural fluorophores encapsulated in the non-biological carrier. By doping biodegradable-polymer drug delivery microspheres with natural or synthetic fluorophores, the desired fluorescence can be attained or biological organisms can be simulated without the associated risks and logistical difficulties of live microorganisms.

  1. Biodegradation of Silk Biomaterials

    OpenAIRE

    Bochu Wang; Yang Cao

    2009-01-01

    Silk fibroin from the silkworm, Bombyx mori, has excellent properties such as biocompatibility, biodegradation, non-toxicity, adsorption properties, etc. As a kind of ideal biomaterial, silk fibroin has been widely used since it was first utilized for sutures a long time ago. The degradation behavior of silk biomaterials is obviously important for medical applications. This article will focus on silk-based biomaterials and review the degradation behaviors of silk materials.

  2. Forgotten biliary stents: ignorance is not bliss.

    Science.gov (United States)

    Kumar, Saket; Chandra, Abhijit; Kulkarni, Rugved; Maurya, Ajeet Pratap; Gupta, Vishal

    2017-06-22

    Endoscopic biliary stenting is a common procedure in routine gastroenterology practice. Plastic stents are the most common type of stents used and are indicated mainly for short-term biliary drainage. Prolonged indwelling plastic stents can result in disastrous complications. We conducted a retrospective analysis of patients who presented with complications of forgotten biliary stents in a tertiary care hospital during January 2010 to October 2016. All patients were managed either by endoscopic or surgical means. Details of these patients were obtained from departmental patient database, endoscopy records, and surgical register. A total of 21 cases of retained biliary stents were managed in the study period and their outcome was analyzed. The median age was 47 years (range 17-70 years) and 17 (80.9%) patients were female. Primary indication of biliary stenting was stone disease in 76.2% (n = 16), while benign biliary stricture accounted for 19% of cases (n = 4). Mean duration at presentation to hospital after ERCP stenting was 3.53 years (range 1-14 years), with cholangitis being the most common presentation (66.67%). Definitive endoscopic treatment for forgotten stent and its associated complication was possible only in five patients (23.8%); in remaining 16 (76.2%) cases, surgical exploration was required. Despite life-threatening complications and major surgical interventions, no mortality was recorded. Instances of forgotten biliary stents presenting with serious complications are not uncommon in Indian setup. Patients either ignore advice for timely stent removal or are unaware of the presence of endoprosthesis or need for removal. Adequate patient counseling, information, and proper documentation are essential to avoid this condition.

  3. Iliocaval Confluence Stenting for Chronic Venous Obstructions

    Energy Technology Data Exchange (ETDEWEB)

    Graaf, Rick de, E-mail: r.de.graaf@mumc.nl [Maastricht University Medical Centre (MUMC), Department of Radiology (Netherlands); Wolf, Mark de, E-mail: markthewolf@gmail.com [Maastricht University Medical Centre (MUMC), Department of Surgery (Netherlands); Sailer, Anna M., E-mail: anni.sailer@mumc.nl [Maastricht University Medical Centre (MUMC), Department of Radiology (Netherlands); Laanen, Jorinde van, E-mail: jorinde.van.laanen@mumc.nl; Wittens, Cees, E-mail: c.wittens@me.com [Maastricht University Medical Centre (MUMC), Department of Surgery (Netherlands); Jalaie, Houman, E-mail: hjalaie@ukaachen.de [University Hospital Aachen, Department of Surgery (Germany)

    2015-10-15

    PurposeDifferent techniques have been described for stenting of venous obstructions. We report our experience with two different confluence stenting techniques to treat chronic bi-iliocaval obstructions.Materials and MethodsBetween 11/2009 and 08/2014 we treated 40 patients for chronic total bi-iliocaval obstructions. Pre-operative magnetic resonance venography showed bilateral extensive post-thrombotic scarring in common and external iliac veins as well as obstruction of the inferior vena cava (IVC). Stenting of the IVC was performed with large self-expandable stents down to the level of the iliocaval confluence. To bridge the confluence, either self-expandable stents were placed inside the IVC stent (24 patients, SECS group) or high radial force balloon-expandable stents were placed at the same level (16 patients, BECS group). In both cases, bilateral iliac extensions were performed using nitinol stents.ResultsRecanalization was achieved for all patients. In 15 (38 %) patients, a hybrid procedure with endophlebectomy and arteriovenous fistula creation needed to be performed because of significant involvement of inflow vessels below the inguinal ligament. Mean follow-up was 443 ± 438 days (range 7–1683 days). For all patients, primary, assisted-primary, and secondary patency rate at 36 months were 70, 73, and 78 %, respectively. Twelve-month patency rates in the SECS group were 85, 85, and 95 % for primary, assisted-primary, and secondary patency. In the BECS group, primary patency was 100 % during a mean follow-up period of 134 ± 118 (range 29–337) days.ConclusionStenting of chronic bi-iliocaval obstruction shows relatively high patency rates at medium follow-up. Short-term patency seems to favor confluence stenting with balloon-expandable stents.

  4. INTRAVASCULAR ULTRASOUND EVALUATING CORONARY STENTS FOR PATIENTS WITH CORONARY ARTERY DISEASE: COMPARED OLD WITH NEW MULTILINK STENTS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective.It was suggested that coronary stent design and coating may affect stent performance and hence induce varying degrees of thrombogenesis and neointimal hyperplasia.The purpose of this study is to compare the 6 month follow up results between old and new Multilink stents with the method of intravascular ultrasound (IVUS) imaging.Methods.We have performed old (n=40) and new (n=35) Multilink stent implantations on 75 patients with coronary artery disease.Coronary angiography was performed before,immediately after,and 6 months after the in stent procedure respectively.Six month follow up IVUS imaging was performed and analyzed off line.Results.Minimal lumen cross sectional area (CSA) of new Multilink stents was significantly larger than that of old Multilink stents (P=0.0053).Mean stent lumen area of new Multilink stents was significantly larger than that of old Multilink stents (P=0.040).Similarly,minimal lumen diameter (MLD) of new Multilink stents was larger than that of old Multilink stents (P= 0.011).Old Multilink stents had a higher percentage of plaque area than new Multilink stents.Conclusion.The new Multilink stent is obviously superior to old Multilink stents,in particular,in the stent MLD and lumen CSA- - major determinants of the restenosis.

  5. Compliance Study of Endovascular Stent Grafts Incorporated with Polyester and Polyurethane Graft Materials in both Stented and Unstented Zones

    Directory of Open Access Journals (Sweden)

    Ying Guan

    2016-08-01

    Full Text Available Compliance mismatch between stent graft and host artery may induce complications and blood flow disorders. However, few studies have been reported on stent graft compliance. This study aims to explore the deformation and compliance of stent graft in stented and unstented zones under three pressure ranges. Compliance of two stent grafts incorporated with polyurethane graft (nitinol-PU and polyester graft (nitinol-PET materials respectively were tested; the stents used in the two stent grafts were identical. For the circumferential deformation of the stent grafts under each pressure range, the nitinol-PET stent graft was uniform in both zones. The nitinol-PU stent graft was circumferentially uniform in the stented zone, however, it was nonuniform in the unstented zone. The compliance of the PU graft material was 15 times higher than that of the PET graft. No significant difference in compliance was observed between stented and unstented zones of the nitinol-PET stent graft regardless of the applied pressure range. However, for the nitinol-PU stent graft, compliance of the unstented PU region was approximately twice that of the stented region; thus, compliance along the length of the nitinol-PU stent graft was not constant and different from that of the nitinol-PET stent graft.

  6. Coronary artery stent geometry and in-stent contrast attenuation with 64-slice computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Schepis, Tiziano; Koepfli, Pascal; Gaemperli, Oliver; Eberli, Franz R.; Luescher, Thomas F. [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); Leschka, Sebastian; Desbiolles, Lotus; Husmann, Lars; Wildermuth, Simon; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiovascular Center, Zurich (Switzerland); Zurich Center for Integrative Human Physiology, Zurich (Switzerland)

    2007-06-15

    We aimed at assessing stent geometry and in-stent contrast attenuation with 64-slice CT in patients with various coronary stents. Twenty-nine patients (mean age 60 {+-} 11 years; 24 men) with 50 stents underwent CT within 2 weeks after stent placement. Mean in-stent luminal diameter and reference vessel diameter proximal and distal to the stent were assessed with CT, and compared to quantitative coronary angiography (QCA). Stent length was also compared to the manufacturer's values. Images were reconstructed using a medium-smooth (B30f) and sharp (B46f) kernel. All 50 stents could be visualized with CT. Mean in-stent luminal diameter was systematically underestimated with CT compared to QCA (1.60 {+-} 0.39 mm versus 2.49 {+-} 0.45 mm; P < 0.0001), resulting in a modest correlation of QCA versus CT (r = 0.49; P < 0.0001). Stent length as given by the manufacturer was 18.2 {+-} 6.2 mm, correlating well with CT (18.5 {+-} 5.7 mm; r = 0.95; P < 0.0001) and QCA (17.4 {+-} 5.6 mm; r = 0.87; P < 0.0001). Proximal and distal reference vessel diameters were similar with CT and QCA (P = 0.06 and P = 0.03). B46f kernel images showed higher image noise (P < 0.05) and lower in-stent CT attenuation values (P < 0.001) than images reconstructed with the B30f kernel. 64-slice CT allows measurement of coronary artery in-stent density, and significantly underestimates the true in-stent diameter compared to QCA. (orig.)

  7. The conical stent in coronary artery improves hemodynamics compared with the traditional cylindrical stent.

    Science.gov (United States)

    Yu, Yi; Zhou, Yujie; Ma, Qian; Jia, Shuo; Wu, Sijing; Sun, Yan; Liu, Xiaoli; Zhao, Yingxin; Liu, Yuyang; Shi, Dongmei

    2017-01-15

    This study sought to explore the efficacy of the conical stent implantation in the coronary artery by comparing the effects of cylindrical and conical stents on wall shear stress (WSS) and velocity of flow and fractional flow reserve (FFR). The traditional cylindrical stent currently used in the percutaneous coronary intervention (PCI) has a consistent diameter, which does not match the physiological change of the coronary artery. On the contrary, as a new patent, the conical stent with tapering lumen is consistent with the physiological change of vascular diameter. However, the effect of the conical stent implantation on the coronary hemodynamics remains unclear. The coronary artery, artery stenosis and two stent models were established by Solidworks software. All models were imported into the computational fluid dynamics (CFD) software ANSYS ICEM-CFD to establish the fluid model. After the boundary conditions were set, CFD analysis was proceeded to compare the effects of two stent implantation on the change of WSS, velocity of flow and FFR. Hemodynamic indexes including FFR, blood flow velocity distribution (BVD) and WSS were improved by either the cylindrical or the conical stent implantation. However, after the conical stent implantation, the change of FFR seemed to be slower and more homogenous; the blood flow velocity was more appropriate without any obvious blood stagnation and direction changes; the WSS after the conical stent implantation was uniform from the proximal to distal side of the stent. Compared with the cylindrical stent, the conical stent implantation in the coronary artery can make the changes of vascular hemodynamic more closer to the physiological condition, which can reduce the incidence of intra-stent restenosis and thrombosis, thus making it more suitable for PCI therapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Crush stenting in treating coronary bifurcate lesions: paclitaxel eluting stents versus sirolimus eluting stents

    Institute of Scientific and Technical Information of China (English)

    CHEN Shao-liang; SUN Xue-wen; HU Da-yi; Tak W. Kwan; ZHANG Jun-jie; YE Fei; CHEN Yun-dai; ZHU Zhong-sheng; LIN Song; TIAN Nai-liang; LIU Zhi-zhong; FANG Wei-yi

    2008-01-01

    Background Because no data regarding the comparison of crush stenting with pactitaxel(PES)or sirolimus eluting stents(SES)for coronary bifurcate lesions have been reported,we compared the clinical outcomes of these two types of stents.Methods Two hundred and thirty patients with 242 bifurcate lesions were enrolled in a prospective,nonrandomized trial.Primary endpoints included myocardial infarction,cardiac death and target vessel revascularization at 8 months.Results All patients were followed up clinically and 82%angiographically at 8 months.Final kissing balloon inflation was performed in 72%in the PES and 75%in the SES groups(P>0.05).Compared to the SES group,PES group had a higher late loss and incidence of restenosis(P=0.04)in the prebifurcation vessel segment.The postbifurcation vessel segment in the PES group had a greater late loss((0.7+0.6)mm vs(0.3±0.4)mm,P<0.001)and higher restenosis in the side branch(25.5%vs 15.6%,P=0.04)when compared to the SES group.There was significant difference of insegment restenosis in the entire main vessel between PES and SES groups (P=0.004).Target lesion revascularization was more frequently seen in the PES group as compared to the SES group(P=0.01).There was significant difference in the accumulative MACE between these two groups(P=0.01).The survival rate free from target lesion revascularization was significantly higher in the SES group when compared to the PES group(P<0.001).Conclusion SES is superior to PES in reducing restenosis and target lesion revascularization by 8-month follow-up after crush stenting for bifurcate lesions.

  9. Anaerobic Biodegradation of Detergent Surfactants

    Directory of Open Access Journals (Sweden)

    Erich Jelen

    2009-03-01

    Full Text Available Detergent surfactantscan be found in wastewater in relevant concentrations. Most of them are known as ready degradable under aerobic conditions, as required by European legislation. Far fewer surfactants have been tested so far for biodegradability under anaerobic conditions. The natural environment is predominantly aerobic, but there are some environmental compartments such as river sediments, sub-surface soil layer and anaerobic sludge digesters of wastewater treatment plants which have strictly anaerobic conditions. This review gives an overview on anaerobic biodegradation processes, the methods for testing anaerobic biodegradability, and the anaerobic biodegradability of different detergent surfactant types (anionic, nonionic, cationic, amphoteric surfactants.

  10. Urethral Pain Among Prostate Cancer Survivors 1 to 14 Years After Radiation Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Pettersson, Niclas, E-mail: niclas.pettersson@vgregion.se [Department of Physics and Biomedical Engineering, Sahlgrenska University Hospital, Goeteborg (Sweden); Olsson, Caroline [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Goeteborg (Sweden); Tucker, Susan L. [Department of Bioinformatics and Computational Biology, University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Alsadius, David; Wilderaeng, Ulrica [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Goeteborg (Sweden); Johansson, Karl-Axel [Department of Physics and Biomedical Engineering, Sahlgrenska University Hospital, Goeteborg (Sweden); Steineck, Gunnar [Division of Clinical Cancer Epidemiology, Department of Oncology, Institute of Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Goeteborg (Sweden)

    2013-01-01

    Purpose: To investigate how treatment-related and non-treatment-related factors impact urethral pain among long-term prostate cancer survivors. Methods and Materials: Men treated for prostate cancer with radiation therapy at the Sahlgrenska University Hospital in Goeteborg, Sweden from 1993 to 2006 were approached with a study-specific postal questionnaire addressing symptoms after treatment, including urethral burning pain during urination (n=985). The men had received primary or salvage external-beam radiation therapy (EBRT) or EBRT in combination with brachytherapy (BT). Prescribed doses were commonly 70 Gy in 2.0-Gy fractions for primary and salvage EBRT and 50 Gy plus 2 Multiplication-Sign 10.0 Gy for EBRT + BT. Prostatic urethral doses were assessed from treatment records. We also recruited 350 non-pelvic-irradiated, population-based controls matched for age and residency to provide symptom background rates. Results: Of the treated men, 16% (137 of 863) reported urethral pain, compared with 11% (27 of 242) of the controls. The median time to follow-up was 5.2 years (range, 1.1-14.3 years). Prostatic urethral doses were similar to prescription doses for EBRT and 100% to 115% for BT. Fractionation-corrected dose and time to follow-up affected the occurrence of the symptom. For a follow-up {>=}3 years, 19% of men (52 of 268) within the 70-Gy EBRT + BT group reported pain, compared with 10% of men (23 of 222) treated with 70 Gy primary EBRT (prevalence ratio 1.9; 95% confidence interval 1.2-3.0). Of the men treated with salvage EBRT, 10% (20 of 197) reported urethral pain. Conclusions: Survivors treated with EBRT + BT had a higher risk for urethral pain compared with those treated with EBRT. The symptom prevalence decreased with longer time to follow-up. We found a relationship between fractionation-corrected urethral dose and pain. Among long-term prostate cancer survivors, the occurrence of pain was not increased above the background rate for prostatic urethral

  11. Bacterial Vaginosis–Associated Bacteria in Men: Association of Leptotrichia/Sneathia spp. With Nongonococcal Urethritis

    Science.gov (United States)

    Manhart, Lisa E.; Khosropour, Christine M.; Liu, Congzhu; Gillespie, Catherine W.; Depner, Kevin; Fiedler, Tina; Marrazzo, Jeanne M.; Fredricks, David N.

    2014-01-01

    Background Approximately 45% of nongonococcal urethritis cases have no identified etiology. Novel bacteria recently associated with bacterial vaginosis (BV) in women may be involved. We evaluated the association of idiopathic nongonococcal urethritis and 5 newly described BV-associated bacteria (BVAB). Methods Heterosexual men 16 years or older attending a sexually transmitted disease clinic in Seattle, Washington, from May 2007 to July 2011 and negative for Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Mycoplasma genitalium, and Ureaplasma urealyticum–biovar2 were eligible. Cases had urethral discharge or 5 or more polymorphonuclear leukocytes per high-power field in urethral exudates. Controls had no urethral discharge and less than 5 polymorphonuclear leukocytes per high-power field. Urine was tested for Atopobium spp., BVAB-2, BVAB-3, Megasphaera spp., and Leptotrichia/Sneathia spp. using quantitative taxon-directed polymerase chain reaction. Results Cases (n = 157) and controls (n = 102) were of similar age, education, and income, and most were white. Leptotrichia/Sneathia spp. was significantly associated with urethritis (24/157 [15.3%] vs. 6/102 [5.9%], P = 0.03). BVAB-2 was more common in cases than in controls (7/157 [4.5%] vs. 1/102 [1.0%], P = 0.15), and BVAB-3 (n = 2) and Megasphaera spp. (n = 1) were only detected in men with urethritis, but these bacteria were found only in men who also had Leptotrichia/Sneathia spp. Atopobium spp. was not associated with urethritis. The quantity of bacteria did not differ between cases and controls. Among treated cases, doxycycline was more effective than azithromycin for clinical cure of men with Leptotrichia/Sneathia spp. (9/10 vs. 7/12, P = 0.16) and BVAB-2 (3/3 vs. 0/3, P = 0.10). Conclusions Leptotrichia/Sneathia spp. may be urethral pathogens or contribute to a pathogenic microbiota that can also include BVAB-2, BVAB-3, and Megasphaera spp. Doxycycline may be more effective than

  12. Docetaxel inhibits urethral stricture formation, an initial study in rabbit model.

    Directory of Open Access Journals (Sweden)

    Delai Fu

    Full Text Available INTRODUCTION: Urethral stricture, a frequent source of lower urinary tract disorders in men, is still a difficult problem for urologists. Based the anti-restenosis effect of paclitaxel on coronary artery, the role of docetaxel, a semi-synthetic analogue of paclitaxel, in limiting urethral stricture formation was studied. METHODS: Forty adult New Zealand male rabbits were involved in this study, which were randomly assigned into 3 groups, namely a high dose docetaxel (DH, 0.1 mg/d, a low dose docetaxel (DL, 0.01 mg/d and a control (C group, with 16, 16, 8 rabbits in each group, respectively. All animals underwent a 10 mm-long circumferential electrocoagulation of the bulbar urethra with a 13Fr pediatric resectoscope. Drugs were given by urethral irrigation daily and continuous for 28 days. Stricture formation was assessed by retrograde urethrography and videourethroscopy. Urethra pathology was evaluated by hematoxylin and eosin staining and Sirius red staining. RESULTS: At the end of this study, 15, 14 and 7 rabbits remained for evaluation in DH, DL and C group, respectively. Urethral diameters in DH, DL and C group were (7.17±1.63 mm, (6.55±0.62 mm, (3.23±1.36 mm, with a normal urethral diameter of (9.08±1.29 mm. Lumen reduction in DH, DL and C group were (36.93±11.58%, (48.03±7.89% and (84.66±14.95%, respectively. Statistically difference could be found between every two groups (p<0.05 both in urethral diameters and in lumen reduction, except for compare of urethral diameters between DH and DL group. Histological examination confirmed mass fibrous tissue and collagen content at the stricture sit in C group, whereas less in docetaxel treated rabbits. CONCLUSIONS: Docetaxel could limit urethral stricture formation, which may be due to inhibition of fibrous tissue and collagen expression. Docetaxel may become a new choice in the prevention of urethral stricture formation.

  13. Evaluation of anterior urethral stricture using thick slab SSFSE MR urethrography.

    Science.gov (United States)

    Park, Byung Kwan; Kim, Chan Kyo; Lee, Sung Won

    2010-12-01

    magnetic resonance urethrography (MRU) can be used for depicting not only anterior urethral strictures but also periurethral anatomy in order to produce a management plan. to determine if thick slab single-shot fast spin echo (SSFSE) MRU is useful for evaluating anterior urethral stricture compared to fast recovery fast spin echo (FRFSE) MRU. Ten patients with benign anterior urethral stricture underwent both thick slab SSFSE MRU and FRFSE MRU using sterile jelly for urethral distension before retrograde urethrography. The glans penis was tied at the time of MRU. The two types of MR image were compared regarding stricture length, scan time, and image quality. We also determined whether or not both of the two MR sequences could display an entire anterior urethra on one image. the stricture length on thick slab SSFSE and FRFSE MRU ranged from 4.0 to 71.3 mm (36.4 ± 21.8 mm) and from 4.0 to 67.5 mm (35.7 ± 20.8 mm), respectively (P > 0.05). The mean scan time for thick slab SSFSE and FRFSE sequences was 2 s and 194 s, respectively (P MRU was inferior to FRFSE MRU (P MRU displayed the entire anterior urethra on one image, while only five FRFSE MRU did so (P MRU can provide a concordant stricture length when compared to the FRFSE MRU and imaging of the entire length of the anterior urethral stricture with subjective reduced image quality and scan time.

  14. PCR for diagnosis of male Trichomonas vaginalis infection with chronic prostatitis and urethritis.

    Science.gov (United States)

    Lee, Jong Jin; Moon, Hong Sang; Lee, Tchun Yong; Hwang, Hwan Sik; Ahn, Myoung-Hee; Ryu, Jae-Sook

    2012-06-01

    The aim of this study was to assess the usefulness of PCR for diagnosis of Trichomonas vaginalis infection among male patients with chronic recurrent prostatitis and urethritis. Between June 2001 and December 2003, a total of 33 patients visited the Department of Urology, Hanyang University Guri Hospital and were examined for T. vaginalis infection by PCR and culture in TYM medium. For the PCR, we used primers based on a repetitive sequence cloned from T. vaginalis (TV-E650). Voided bladder urine (VB1 and VB3) was sampled from 33 men with symptoms of lower urinary tract infection (urethral charge, residual urine sensation, and frequency). Culture failed to detect any T. vaginalis infection whereas PCR identified 7 cases of trichomoniasis (21.2%). Five of the 7 cases had been diagnosed with prostatitis and 2 with urethritis. PCR for the 5 prostatitis cases yielded a positive 330 bp band from bothVB1 and VB3, whereas positive results were only obtained from VB1 for the 2 urethritis patients. We showed that the PCR method could detect T. vaginalis when there was only 1 T. vaginalis cell per PCR mixture. Our results strongly support the usefulness of PCR on urine samples for detecting T. vaginalis in chronic prostatitis and urethritis patients.

  15. Microfabrication and nanotechnology in stent design.

    Science.gov (United States)

    Martinez, Adam W; Chaikof, Elliot L

    2011-01-01

    Intravascular stents were first introduced in the 1980s as an adjunct to primary angioplasty for management of early complications, including arterial dissection, or treatment of an inadequate technical outcome due to early elastic recoil of the atherosclerotic lesion. Despite the beneficial effects of stenting, persistent high rates of restenosis motivated the design of drug-eluting stents for delivery of agents to limit the proliferative and other inflammatory responses within the vascular wall that contribute to the development of a restenotic lesion. These strategies have yielded a significant reduction in the incidence of restenosis, but challenges remain, including incomplete repair of the endothelium at the site of vascular wall injury that may be associated with a late risk of thrombosis. A failure of vessel wall healing has been attributed primarily to the use of polymeric stent coatings, but the effects of the eluted drug and other material properties or design features of the stent cannot be excluded. Improvements in stent microfabrication, as well as the introduction of alternative materials may help to address those limitations that inhibit stent performance. This review describes the application of novel microfabrication processes and the evolution of new nanotechnologies that hold significant promise in eliminating existing shortcomings of current stent platforms.

  16. Rescue coronary stenting in acute myocardial infarction

    Science.gov (United States)

    Barbieri, Enrico; Meneghetti, Paolo; Molinari, Gionata; Zardini, Piero

    1996-01-01

    Failed rescue coronary angioplasty is a high risk situation because of high mortality. Coronary stent has given us the chance of improving and maintaining the patency of the artery. We report our preliminary experience of rescue stenting after unsuccessful coronary angioplasty.

  17. 21 CFR 876.4620 - Ureteral stent.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ureteral stent. 876.4620 Section 876.4620 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Surgical Devices § 876.4620 Ureteral stent. (a) Identification. A ureteral...

  18. Routine intraoperative stenting for renal transplant recipients.

    Science.gov (United States)

    Wilson, Colin H; Bhatti, Aftab A; Rix, David A; Manas, Derek M

    2005-10-15

    Major urological complications (MUCs) after kidney transplantation contribute to patient morbidity and compromise graft function. Ureteric stents have been successfully used to treat such complications and a number of centers have adopted a policy of universal prophylactic stenting, at the time of graft implantation, to reduce the incidence of urine leaks and ureteric stenosis. In conjunction with the Cochrane Renal Group we searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, reference lists of articles, books and abstracts and contacted companies, authors and experts to identify randomized controlled trials examining the use of stents in renal transplantation. The primary outcome was the incidence of MUCs and data on this statistic was pooled and analyzed using a random effects model. Seven randomized controlled trials (1154 patients) of low or moderate quality were identified. The incidence of MUCs was significantly reduced (relative risk [RR] 0.24; 95% CI: 0.07 - 0.77; P=0.02; number needed to treat = 13) by prophylactic ureteric stenting. Urinary tract infections were more common in stented patients (RR 1.49), unless the patients were prescribed 480 mg cotrimoxazole once daily. With this antibiotic regime the incidence of infection was equivalent between the two groups (RR 0.97). Stents appeared generally well tolerated, although trials using longer stents (> or = 20 cm) for longer periods of time (>6 weeks) reported more problems with encrustation and migration. Universal prophylactic stenting reduces the incidence of MUCs and should be recommended on the basis of currently available randomized controlled trials.

  19. Drug eluting stents: Current status and new developments

    NARCIS (Netherlands)

    G. Ertaş; H.M.M. van Beusekom (Heleen)

    2012-01-01

    textabstractDespite the favorable impact of drug eluting stents on stent restenosis, their long-term reliability is considered worrisome by some because of stent thrombosis. Often attributed to adverse reactions to the stent platform, both the drugs and polymer characteristics have been further adva

  20. Bacterial colonization of double J stents and bacteriuria frequency

    Directory of Open Access Journals (Sweden)

    Berat Cem Ozgur

    2013-12-01

    Full Text Available Stents and catheters are widely used in urology. In this study, the frequency of double J (DJ stent colonization and stent-associated bacteriuria was investigated. Between June 2011 and June 2012, 130 patients (17–72 years old who underwent DJ stenting were enrolled in the study. Surgeries prior to stenting included stone extraction/lithotripsy, endopyelotomy, and diagnostic ureteroscopy. Prior to stenting, sterile urine samples were obtained, and urinary cultures were performed upon removal of the DJ stents, the second procedure. DJ stent cultures were also performed. Sixty-three stents were inserted into the right ureter and 67 into the left ureter of the patients. Cultures showed bacterial colonization in 10 (7.7% cases. There was no significant association between positive stent culture and patient age, sex, or stent laterality. The rate of colonization was 2.2%, 2.9%, and 25% when indwelling time was less than 4 weeks, 4–6 weeks, and more than 6 weeks, respectively. In the present study, the rate of infection associated with a DJ stent and urinary infection was not very high. However, bacterial colonization increases significantly with indwelling time of the stent, and sterile culture of urine does not rule out colonization of the stent. Bacteriological investigation showed very low rates of colonization within 6 weeks after the insertion of stents, indicating that ureteral stents can be used safely within that time period.

  1. Drug eluting stents: Current status and new developments

    NARCIS (Netherlands)

    G. Ertaş; H.M.M. van Beusekom (Heleen)

    2012-01-01

    textabstractDespite the favorable impact of drug eluting stents on stent restenosis, their long-term reliability is considered worrisome by some because of stent thrombosis. Often attributed to adverse reactions to the stent platform, both the drugs and polymer characteristics have been further

  2. Mesenchymal stem cell seeding promotes reendothelialization of the endovascular stent.

    Science.gov (United States)

    Wu, Xue; Wang, Guixue; Tang, Chaojun; Zhang, Dechuan; Li, Zhenggong; Du, Dingyuan; Zhang, Zhengcai

    2011-09-01

    This study is designed to make a novel cell seeding stent and to evaluate reendothelialization and anti-restenosis after the stent implantation. In comparison with cell seeding stents utilized in previous studies, Mesenchymal stem cells (MSCs) have advantages on promoting of issue repair. Thus it was employed to improve the reendothelialization effects of endovascular stent in present work. MSCs were isolated by density gradient centrifugation and determined as CD29(+) CD44(+) CD34(-) cells by immunofluorescence and immunocytochemistry; gluten and polylysine coated stents were prepared by ultrasonic atomization spray, and MSCs seeded stents were made through rotation culture according to the optimized conditions that were determined in previous studies. The results from animal experiments, in which male New Zealand white rabbits were used, show that the reendothelialization of MSCs coated stents can be completed within one month; in comparison with 316L stainless steel stents (316L SS stents) and gluten and polylysine coated stents, the intimal hyperplasia and in-stent restenosis are significantly inhibited by MSCs coated stents. Endovascular stent seeded with MSCs promotes reendothelialization and inhibits the intimal hyperplasia and in-stent restenosis compared with the 316L SS stents and the gluten and polylysine coated stents.

  3. Secreted Matrix Metalloproteinase-9 of Proliferating Smooth Muscle Cells as a Trigger for Drug Release from Stent Surface Polymers in Coronary Arteries.

    Science.gov (United States)

    Gliesche, Daniel G; Hussner, Janine; Witzigmann, Dominik; Porta, Fabiola; Glatter, Timo; Schmidt, Alexander; Huwyler, Jörg; Meyer Zu Schwabedissen, Henriette E

    2016-07-01

    Cardiovascular diseases are the leading causes of death in industrialized countries. Atherosclerotic coronary arteries are commonly treated with percutaneous transluminal coronary intervention followed by stent deployment. This treatment has significantly improved the clinical outcome. However, triggered vascular smooth muscle cell (SMC) proliferation leads to in-stent restenosis in bare metal stents. In addition, stent thrombosis is a severe side effect of drug eluting stents due to inhibition of endothelialization. The aim of this study was to develop and test a stent surface polymer, where cytotoxic drugs are covalently conjugated to the surface and released by proteases selectively secreted by proliferating smooth muscle cells. Resting and proliferating human coronary artery smooth muscle cells (HCASMC) and endothelial cells (HCAEC) were screened to identify an enzyme exclusively released by proliferating HCASMC. Expression analyses and enzyme activity assays verified selective and exclusive activity of the matrix metalloproteinase-9 (MMP-9) in proliferating HCASMC. The principle of drug release exclusively triggered by proliferating HCASMC was tested using the biodegradable stent surface polymer poly-l-lactic acid (PLLA) and the MMP-9 cleavable peptide linkers named SRL and AVR. The specific peptide cleavage by MMP-9 was verified by attachment of the model compound fluorescein. Fluorescein release was observed in the presence of MMP-9 secreting HCASMC but not of proliferating HCAEC. Our findings suggest that cytotoxic drug conjugated polymers can be designed to selectively release the attached compound triggered by MMP-9 secreting smooth muscle cells. This novel concept may be beneficial for stent endothelialization thereby reducing the risk of restenosis and thrombosis.

  4. Foreign body contamination during stent implantation.

    Science.gov (United States)

    Whelan, D M; van Beusekom, H M; van der Giessen, W J

    1997-03-01

    The treatment of coronary artery disease using stents has become a widely accepted technique. However, the inadvertent co-implantation of contaminating factors with the stent has received little attention. We studied histological cross-sections of stented porcine coronary arteries and observed contamination of some vessels with surgical glove powder and textile fibres. The contaminating particles were associated with a foreign body reaction. Such a reaction could delay the wound-healing response of a stented vessel and thereby prolong the period in which subacute thrombosis could occur. It is also proposed that air contamination could affect the thrombogenicity of the stent. Appropriate measures should be followed to reduce the chance of contamination occurring.

  5. Stent graft placement for dysfunctional arteriovenous grafts

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Gyeong Sik [Dept. of Radiology, CHA Bundang Medical Center, College of Medicine, CHA University, Seongnam (Korea, Republic of); Shin, Byung Seok; Ohm, Joon Young; Ahn, Moon Sang [Chungnam National University Hospital, Daejeon (Korea, Republic of)

    2015-07-15

    This study aimed to evaluate the usefulness and outcomes of stent graft use in dysfunctional arteriovenous grafts. Eleven patients who underwent stent graft placement for a dysfunctional hemodialysis graft were included in this retrospective study. Expanded polytetrafluoroethylene covered stent grafts were placed at the venous anastomosis site in case of pseudoaneurysm, venous laceration, elastic recoil or residual restenosis despite the repeated angioplasty. The patency of the arteriovenous graft was evaluated using Kaplan-Meier analysis. Primary and secondary mean patency was 363 days and 741 days. Primary patency at 3, 6, and 12 months was 82%, 73%, and 32%, respectively. Secondary patency at the 3, 6, 12, 24, and 36 months was improved to 91%, 82%, 82%, 50%, and 25%, respectively. Fractures of the stent graft were observed in 2 patients, but had no effect on the patency. Stent graft placement in dysfunctional arteriovenous graft is useful and effective in prolonging graft patency.

  6. Atrial septal stenting - How I do it?

    Directory of Open Access Journals (Sweden)

    Kothandam Sivakumar

    2015-01-01

    Full Text Available A wide atrial communication is important to maintain hemodynamics in certain forms of congenital and acquired heart defects. In comparison to balloon septostomy or blade septostomy, atrial septal stenting provides a controlled, predictable, and long-lasting atrial communication. It often needs a prior Brockenbrough needle septal puncture to obtain a stable stent position. A stent deployed across a previously dilated and stretched oval foramen or tunnel form of oval foramen carries higher risk of embolization. This review provides technical tips to achieve a safe atrial septal stenting. Even though this is a "How to do it article," an initial discussion about the indications for atrial septal stenting is vital as the resultant size of the atrial septal communication should be tailored for each indication.

  7. Biodegradable and compostable alternatives to conventional plastics

    National Research Council Canada - National Science Library

    J. H. Song; R. J. Murphy; R. Narayan; G. B. H. Davies

    2009-01-01

    .... Recently, significant progress has been made in the development of biodegradable plastics, largely from renewable natural resources, to produce biodegradable materials with similar functionality...

  8. Balloon-expandable Metallic Stents for Airway Diseases.

    Science.gov (United States)

    Ohki, Takashi; Sugimoto, Seiichiro; Kurosaki, Takeshi; Otani, Shinji; Miyoshi, Kentaroh; Yamane, Masaomi; Miyoshi, Shinichiro; Oto, Takahiro

    2016-10-01

    Stent placement is an essential treatment for airway diseases. Although self-expandable metallic stents and silicone stents are commonly applied for the treatment of airway diseases, these stents are unsuitable for the treatment of small airway diseases encountered in pediatric patients and lung transplant recipients with airway complications. Currently, only vascular balloon-expandable metallic stents are available for the treatment of small airway diseases; however, little research has been conducted on the use of these stents in this field. We have launched a prospective feasibility study to clarify the safety and efficacy of balloon-expandable metallic stents for the treatment of airway diseases.

  9. Call for standards in technical documentation of intracoronary stents.

    Science.gov (United States)

    Lanzer, Peter; Gijsen, Frank J H; Topoleski, L D Timmie; Holzapfel, Gerhard A

    2010-01-01

    At present, the product information of intracoronary stents provided by the industry contains only limited technical data restricting judgments on the in vivo performance of individual products. Available experimental and clinical evidence suggests that interventional target sites display highly heterogeneous biomechanical behavior needed to be matched by specific stent and stent delivery system characteristics. To allow individualized stent-lesion matching, both, understanding of biomechanical properties of the atherosclerotic coronary artery lesions and expert knowledge of the intracoronary stent systems, are required. Here, the authors review some of the initial data on mechanical properties of coronary artery lesions potentially relevant to stenting and suggest standards for technical documentation of intracoronary stents.

  10. Etiology of male urethral strictures-Evaluation of temporal changes at a single center, and review of the literature

    Directory of Open Access Journals (Sweden)

    C.F. Heyns

    2012-03-01

    Conclusions: Over the past 15 years there was an increase in education levels, illegal drug usage and number of sex partners in men with urethral strictures. There was a decrease in urethritis and external trauma, and an increase in iatrogenic trauma as stricture etiology.

  11. Challenges in the Diagnosis and Management of Acquired Nontraumatic Urethral Strictures in Boys in Yaoundé, Cameroon

    Science.gov (United States)

    Mouafo Tambo, F. F.; Fossi kamga, G.; Kamadjou, C.; Mbouche, L.; Nwaha Makon, A. S.; Birraux, J.; Andze, O. G.; Angwafo, F. F.; Mure, P. Y.

    2016-01-01

    Introduction. Urethral strictures in boys denote narrowing of the urethra which can be congenital or acquired. In case of acquired strictures, the etiology is iatrogenic or traumatic and rarely infectious or inflammatory. The aim of this study was to highlight the diagnostic and therapeutic difficulties of acquired nontraumatic urethral strictures in boys in Yaoundé, Cameroon. Methodology. The authors report five cases of nontraumatic urethral strictures managed at the Pediatric Surgery Department of the YGOPH over a two-year period (November 2012–November 2014). In order to confirm the diagnosis of urethral stricture, all patients were assessed with both cystourethrography and urethrocystoscopy. Results. In all the cases the urethra was inflammatory with either a single or multiple strictures. The surgical management included internal urethrotomy (n = 1), urethral dilatation (n = 1), vesicostomy (n = 2), and urethral catheterization (n = 3). With a median follow-up of 8.2 months (4–16 months) all patients remained symptoms-free. Conclusion. The authors report the difficulties encountered in the diagnosis and management of nontraumatic urethral strictures in boys at a tertiary hospital in Yaoundé, Cameroon. The existence of an inflammatory etiology of urethral strictures in boys deserves to be considered. PMID:27239364

  12. Urethral glands of the male mouse contain secretory component and immunoglobulin A plasma cells and are targets of testosterone.

    Science.gov (United States)

    Parr, M B; Ren, H P; Russell, L D; Prins, G S; Parr, E L

    1992-12-01

    The occurrence and possible functions of mucosal immunity in the male urogenital tract have not been extensively investigated. In this study we used immunolabeling to localize secretory component (SC) and immunoglobulin (Ig) A in the urogenital tract of the male mouse. SC was located in the ventral prostate, while SC and IgA plasma cells were both detected in the urethral glands in the pelvic and bulbous portions of the urethra. SC and IgA were not observed elsewhere in the urogenital tract. We also examined the ventral prostate and urethral glands of sham-castrated, oil-treated castrated, and testosterone-treated castrated mice. There was a striking reduction in the size of the ventral prostate and urethral glands in oil-treated castrates compared to the other two groups, based on gross and histological morphology. Morphometric analysis showed that the cell and nuclear sizes of the urethral gland acinar cells were reduced after castration and restored to normal size by testosterone treatment. Androgen receptors (AR) were localized in the nuclei of urethral gland cells by immunocytochemistry using anti-AR antibodies. Labeling of SC and IgA plasma cells was similar in the urethral glands and ventral prostates of sham- and testosterone-treated castrates, but was reduced or absent at these sites in oil-treated castrates. These studies show that the ventral prostate and urethral glands may be sites for secretory immunity in the male murine urogenital tract, and that the urethral glands are targets for testosterone.

  13. Updates on the use of ureteral stents: focus on the Resonance® stent

    Directory of Open Access Journals (Sweden)

    Thomas MT Turk

    2010-12-01

    Full Text Available Manoj V Rao, Anthony J Polcari, Thomas MT TurkDepartment of Urology, Loyola University Medical Center, Maywood, IL, USAAbstract: The Resonance® metallic ureteral stent is one of the latest additions to the urologist’s armamentarium in managing ureteral obstruction. One advantage of this stent over traditional polymer-based stents is resistance to encrustation with stone material, which allows longer dwell times and less frequent exchange procedures. Although exchanging a metallic stent is slightly more complicated than exchanging a polymer stent, the fluoroscopic techniques required are familiar to most urologists. The Resonance stent is also more resistant to compression by external forces, potentially allowing greater applicability in patients with metastatic cancer. Furthermore, the use of this stent in patients with benign ureteral obstruction is shown to be associated with significant cost reduction. Clinical studies on the use of this stent are accumulating and the results are mixed, although Level 1 evidence is lacking. In this article we present a comprehensive review of the available literature on the Resonance metallic ureteral stent.Keywords: resonance, metallic, ureteral, stent, obstruction

  14. Biliary stenting: indications, choice of stents and results: European Society of Gastrointestinal Endoscopy (ESGE) clinical guideline.

    Science.gov (United States)

    Dumonceau, J-M; Tringali, A; Blero, D; Devière, J; Laugiers, R; Heresbach, D; Costamagna, G

    2012-03-01

    This article is part of a combined publication that expresses the current view of the European Society of Gastrointestinal Endoscopy about endoscopic biliary stenting. The present Clinical Guideline describes short-term and long-term results of biliary stenting depending on indications and stent models; it makes recommendations on when, how, and with which stent to perform biliary drainage in most common clinical settings, including in patients with a potentially resectable malignant biliary obstruction and in those who require palliative drainage of common bile duct or hilar strictures. Treatment of benign conditions (strictures related to chronic pancreatitis, liver transplantation, or cholecystectomy, and leaks and failed biliary stone extraction) and management of complications (including stent revision) are also discussed. A two-page executive summary of evidence statements and recommendations is provided. A separate Technology Review describes the models of biliary stents available and the stenting techniques, including advanced techniques such as insertion of multiple plastic stents, drainage of hilar strictures, retrieval of migrated stents and combined stenting in malignant biliary and duodenal obstructions.The target readership for the Clinical Guideline mostly includes digestive endoscopists, gastroenterologists, oncologists, radiologists, internists, and surgeons while the Technology Review should be most useful to endoscopists who perform biliary drainage.

  15. Hybrid stent device of flow-diverting effect and stent-assisted coil embolization formed by fractal structure.

    Science.gov (United States)

    Kojima, Masahiro; Irie, Keiko; Masunaga, Kouhei; Sakai, Yasuhiko; Nakajima, Masahiro; Takeuchi, Masaru; Fukuda, Toshio; Arai, Fumihito; Negoro, Makoto

    2016-05-01

    This paper presents a novel hybrid medical stent device. This hybrid stent device formed by fractal mesh structures provides a flow-diverting effect and stent-assisted coil embolization. Flow-diverter stents decrease blood flow into an aneurysm to prevent its rupture. In general, the mesh size of a flow-diverter stent needs to be small enough to prevent blood flow into the aneurysm. Conventional flow-diverter stents are not available for stent-assisted coil embolization, which is an effective method for aneurysm occlusion, because the mesh size is too small to insert a micro-catheter for coil embolization. The proposed hybrid stent device is capable of stent-assisted coil embolization while simultaneously providing a flow-diverting effect. The fractal stent device is composed of mesh structures with fine and rough mesh areas. The rough mesh area can be used to insert a micro-catheter for stent-assisted coil embolization. Flow-diverting effects of two fractal stent designs were composed to three commercially available stent designs. Flow-diverting effects were analyzed using computational fluid dynamics (CFD) analysis and particle image velocimetry (PIV) experiment. Based on the CFD and PIV results, the fractal stent devices reduce the flow velocity inside an aneurism just as much as the commercially available flow-diverting stents while allowing stent-assisted coil embolization.

  16. Transient coronary aneurysm formation after Nevo™ stent implantation versus persistent coronary aneurysm after Cypher Select™ stent implantation

    DEFF Research Database (Denmark)

    Christiansen, Evald Høj; Lassen, Jens Flensted; Jensen, Lisette Okkels

    2011-01-01

    We implanted a Cypher Select™ coronary stent and two months later a Nevo™ sirolimus-eluting coronary stent in another vessel. At a prescheduled angiographic follow-up, coronary aneurysms were seen in the two stented segments, 6 and 8 months after stent implantation, respectively. Six months later...

  17. Retrospective study to characterize post-obstructive diuresis in cats with urethral obstruction.

    Science.gov (United States)

    Francis, Brenda J; Wells, Raegan J; Rao, Sangeeta; Hackett, Timothy B

    2010-08-01

    Urethral obstruction is a common medical emergency in cats. Frequency of post-obstruction diuresis in cats following resolution of urethral obstruction is unknown. The objective of this study was to document frequency and associated clinical features of post-obstruction diuresis in cats. The records of 32 cats undergoing 33 admissions to the Colorado State University Veterinary Hospital for urethral obstruction were reviewed. Signalment, admission blood values, fluid therapy, and urine output were recorded. Diuresis was defined as urine output greater than 2ml/kg/h. Post-obstructive diuresis occurred in 46% (13/28) of cats within the first 6h of treatment. Occurrence of post-obstructive diuresis was statistically more likely in cats with venous pHdiuresis.

  18. [Can bladder catheterization in pediatrics cause complications? The case of a urethral dysuria cystograph].

    Science.gov (United States)

    Alcázar García, A; Daviu Llorens, E; Daza Laguna, A; Durán Feliubadalo, C; Pons Torrents, X

    2009-10-01

    A urethral dysuria cystograph (CUMS (Cistografia Ureteral Miccional Seriada)) is the first diagnostic procedure, by means of x-rays, to evaluate bladder-urethral reflux. It consists of a bladder catheter to administer a radiopaque contrast dye through the ureter. To use the aforementioned technique without any asepsis measures and without knowledge about it can lead to possible complications. By means of a retrospective study using a sample of 181 patients, the authors have evaluated the incidence of possible complications and/or subsequent discomfort due to a urethral dysuria cystograph (CUMS). As final results, by means of an after test telephone call, the authors observed that 96.7% of the children who underwent this technique did not manifest any type of complication nor urinary discomfort.

  19. Fundamentals and clinical perspective of urethral sphincter instability as a contributing factor in patients with lower urinary tract dysfunction--ICI-RS 2014

    NARCIS (Netherlands)

    Kirschner-Hermanns, Ruth; Anding, Ralf; Rosier, Peter; Birder, Lori; Andersson, Karl Erik; Djurhuus, Jens Christian

    2016-01-01

    AIMS: Urethral pathophysiology is often neglected in discussions of bladder dysfunction. It has been debated whether "urethral sphincter instability," referred to based on observed "urethral pressure variations," is an important aspect of overactive bladder syndrome (OAB). The purpose of this report

  20. MR safety and imaging of neuroform stents at 3T.

    Science.gov (United States)

    Nehra, Arvind; Moran, Christopher J; Cross, Dewitte T; Derdeyn, Colin P

    2004-10-01

    The Neuroform stent is a self-expanding nitinol stent designed for use in wide-necked intracranial aneurysms. Heating and imaging artifacts were evaluated by using a porcine carotid artery aneurysm model in a 3T MR system. A suspended Neuroform stent was tested for deflection. No heating was measured, and no evidence of deflection of the stent was found. Imaging artifacts were minimal. MR imaging in patients with Neuroform stent-treated aneurysms is safe and feasible.

  1. Endothelial responses of magnesium and other alloying elements in magnesium-based stent materials

    Science.gov (United States)

    Zhao, Nan; Zhu, Donghui

    2016-01-01

    Biodegradable tailored magnesium (Mg) alloys are some of the most promising scaffolds for cardiovascular stents. During the course of degradation after implantation, all the alloying elements in the scaffold will be released to the surrounding vascular tissues. However, fundamental questions regarding the toxicity of alloying elements towards vascular cells, the maximum amount of each element that could be used in alloy design, or how each of the alloying elements affects vascular cellular activity and gene expression, are still not fully answered. This work systematically addressed these questions by revealing how application of different alloying elements commonly used in Mg stent materials influences several indices of human endothelial cell health, i.e., viability, proliferations, cytoskeletal reorganizations, migration, and the gene expression profile. The overall cell viability and proliferation showed a decreasing trend with increasing concentrations of the ions, and the half maximal effective concentrations (EC50) for each element were determined. When applied at a low concentration of around 10 mM, Mg had no adverse effects but improved cell proliferation and migration instead. Mg ions also altered endothelial gene expression significantly in a dose dependent manner. Most of the changed genes are related to angiogenesis and the cell adhesion signaling pathways. Findings from this work provide useful information on maximum safe doses of these ions for endothelial cells, endothelial responses towards these metal ions, and some guidance for future Mg stent design. PMID:25363018

  2. Headache after carotid artery stenting.

    Science.gov (United States)

    Suller Marti, A; Bellosta Diago, E; Velázquez Benito, A; Tejero Juste, C; Santos Lasaosa, S

    2017-04-18

    Headache after carotid artery stenting is a headache with onset during the procedure or in the first few hours after it, and where there is no evidence to suggest a complication of that procedure. The purpose of this study is to describe the main features of these headaches based on our clinical experience. Observational prospective study of a sample of patients undergoing carotid artery stenting at Hospital Clínico Universitario Lozano Blesa, in Zaragoza, Spain. We recorded sociodemographic characteristics, cardiovascular risk factors, carotid artery disease, and history of primary headache; data were gathered using structured interviews completed before and 24hours after the procedure. We included 56 patients (mean age 67±9.52 years); 84% were men. Twelve patients (21.4%) experienced headache, 83.3% of whom were men; mean age was 60.58±9.31 years. Headache appeared within the first 6hours in 7 patients (58.4%) and during the procedure in 4 (33.3%). Pain lasted less than 10minutes in 4 patients (33.3%) and between 10 and 120minutes in 5 (41.7%). Headache affected the frontotemporal area in 7 patients (58.3%); 7 patients (58.3%) described pain as unilateral. It was oppressive in 8 patients (66.7%) and of moderate intensity in 6 (50%). Nine patients (75%) required no analgesics. We found no statistically significant associations with any of the variables except for age (P=.007; t test). In our sample, headache after carotid artery stenting was mild to moderate in intensity, unilateral, oppressive, and short-lasting. Further studies are necessary to gain a deeper knowledge of its characteristics and associated risk factors. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  3. Biodegradable micromechanical sensors

    DEFF Research Database (Denmark)

    Keller, Stephan Sylvest; Greve, Anders; Schmid, Silvan

    of mechanical and thermal properties of polymers. For example, measurements of the resonance frequency of cantilevers were used to characterize thin polymer coatings in various environmental conditions [2]. Also, the influence of humidity on the Young’s modulus of SU-8 was evaluated [3]. However, introduction...... of biopolymers to microfabrication is challenging, as these polymers are affected by common processes such as photolithography or wet etching. Here, we present two methods for fabrication of biodegradable micromechanical sensors. First, we fabricated bulk biopolymer microcantilevers using nanoimprint lithography...

  4. Risk Factors for Urinary Tract Infection following Mid Urethral Sling Surgery.

    Science.gov (United States)

    Vigil, Humberto R; Mallick, Ranjeeta; Nitti, Victor W; Lavallée, Luke T; Breau, Rodney H; Hickling, Duane R

    2017-05-01

    Mid urethral sling surgery is common. Postoperative urinary tract infection rates vary in the literature and independent risk factors for urinary tract infection are not well defined. We sought to determine the incidence of and risk factors for urinary tract infection following mid urethral sling surgery. A retrospective cohort of females who underwent sling surgery was captured from the 2006 to 2014 NSQIP® (National Surgical Quality Improvement Program®) database. Exclusion criteria included male gender, nonelective surgery, totally dependent functional status, preoperative infection, prior surgery within 30 days, ASA® (American Society of Anesthesiologists®) Physical Status Classification 4 or greater, concomitant procedure and operative time greater than 60 minutes. The primary outcome was the incidence of urinary tract infection within 30 days of mid urethral sling surgery. Risk factors for urinary tract infection were assessed by examining patient demographic, comorbidity and surgical variables. Logistic regression analyses were performed to estimate the ORs of individual risk factors. Multivariable logistic regression was then performed to adjust for confounding. A total of 9,022 mid urethral sling surgeries were identified. The urinary tract infection incidence was 2.6%. Factors independently associated with an increased infection risk included age greater than 65 years (OR 1.54, 95% CI 1.07-2.22), body mass index greater than 40 kg/m(2) (OR 1.89, 95% CI 1.23-2.92) and hospital admission (OR 2.06, 95% CI 1.37-3.11). Mid urethral sling surgery performed by urologists carried a reduced risk of infection compared to the surgery done by gynecologists (OR 0.52, 95% CI 0.40-0.69). The urinary tract infection risk following mid urethral sling surgery in NSQIP associated hospitals is low. Novel patient and surgical factors for postoperative urinary tract infection have been identified and merit further study. Copyright © 2017 American Urological Association

  5. Internal urethrotomy versus plasmakinetic energy for surgical treatment of urethral stricture

    Directory of Open Access Journals (Sweden)

    Levent Ozcan

    2015-07-01

    Full Text Available Purpose: we aimed to compare the longterm outcome of surgical treatment of urethral stricture with the internal urethrotomy and plasmakinetic energy. Material and Methods: 60 patients, who have been operated due to urethral stricture were enrolled in our clinic. None of the patients had a medical history of urethral stricture. The urethral strictures were diagnosed by clinical history, uroflowmetry, ultrasonography and urethrography. The patients were divided two groups. Group 1 consisted of 30 patients treated with plasmakinetic urethrotomy and group 2 comprised 30 men treated with cold knife urethrotomy. Results: There were no statistically significant differences between two groups in terms of patient age, maximum flow rate (Qmax and quality of life score (Qol value. A statistical difference between the two groups was observed when we compared the 3rd-month uroflowmetry results. Group 1 patients had a mean postoperative Qmax value of 16,1 ± 2,3 ml/s, whereas group 2 had a mean postoperative Qmax value of 15,1 ± 2,2 ml/s (p < 0.05. In the cold knife group, 3 of 11 (27,7% recurrences appeared within the first 3 months, whereas in the plasmakinetic group zero recurrences appeared within the first 3 months in our study. The urethral stricture recurrence rate up to the 12 month period was statistically significant for group 1 (n = 7, 23% compared with group 2 (n = 11, 37% (p < 0.05. Conclusion: We believe that plasmakinetic surgery is better method than the cold knife technique for the treatment of urethral stricture.

  6. Advances in Surgical Reconstructive Techniques in the Management of Penile, Urethral, and Scrotal Cancer.

    Science.gov (United States)

    Bickell, Michael; Beilan, Jonathan; Wallen, Jared; Wiegand, Lucas; Carrion, Rafael

    2016-11-01

    This article reviews the most up-to-date surgical treatment options for the reconstructive management of patients with penile, urethral, and scrotal cancer. Each organ system is examined individually. Techniques and discussion for penile cancer reconstruction include Mohs surgery, glans resurfacing, partial and total glansectomy, and phalloplasty. Included in the penile cancer reconstruction section is the use of penile prosthesis in phalloplasty patients after penectomy, tissue engineering in phallic regeneration, and penile transplantation. Reconstruction following treatment of primary urethral carcinoma and current techniques for scrotal cancer reconstruction using split-thickness skin grafts and flaps are described.

  7. Bacteriological finding in the urethra in men with and without non-gonococcal urethritis

    Directory of Open Access Journals (Sweden)

    Tiodorović Jelica

    2007-01-01

    Full Text Available Background/Aim. Non-gonococcal urethritis (NGU is a very common sexually transmitted disease. The etiology of the disease is complex and not completely solved. The aim of this study was to determine the bacteriological finding in the urethra in men with and without non-gonococcal utethritis. Methods. The study group comprised 200 men with symptoms of urethritis. The control group consisted of 60 men without symptoms of urethritis. The diagnosis of nongonococcal infection was made by finding of an increased number of polymorphonuclear leukocytes (≥ 5 under the microscope in a sample of Gram-stain of urethral smear (× 1 000 and without evidence of Neisseria. gonorrhoeae in specimens (negative direct microscopy and cell culture. Bacteriological examination included: direct microscopy with the Gramstained and methylblue-stained smears of urethral discharges, and cultivation of specimens under the aerobic/unaerobic conditions. In addition to standard bacterial examination and performinig direct imunofluorescence test to detect Chlamydia trachomatis (bioMerieux, France, urethral smears were also examined for the presence of Ureaplasma urealyticum and Mycoplasma hominis by commercially available Mycofast Evolution 2 test (International Microbio, France. The finding of mycoplasmas ≥ 104 CCU/ml was positive. The data were statistically analyzed using Pearson χ2 and Student t test. Results. C. trachomatis was predominant bacterial species found in urethra in men with nongonococcal urethritis. It was isolated alone and/or mixed with mycoplasmas and/or other bacteria in 86 (43.0% of examinees. There was statistically significant difference in finding of C. trachomatis between the study group and the control group (p < 0.001. U. urealyticum was found in men with NGU: 30.2% were with C. trachomatis and 36.0% were without C. trachomatis (p > 0.05. In 16 (8.0% men with NGU, C. trachomatis was isolated alone, while in 13.0% examinees it occurred with U

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

    Science.gov (United States)

    Kuhelj, Dimitrij; Berden, Pavel; Podnar, Tomaž

    2016-03-01

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

  9. EMPREGO DE STENTS CEREBRAIS NAS PATOLOGIAS CEREBROVASCULARES

    Directory of Open Access Journals (Sweden)

    Laís Rocha Lopes

    2015-06-01

    Full Text Available Objective: To understand the applicability and characteristics of the stents for the treatment of cerebrovascular pathologies in order to understand its viability for the therapy. Methods: Scientific articles were used based on electronic search as PubMed, Scientific Electronic Library Online (SciELO, Intechopen, Medscape. An international and up to date source of articles was used. Results: Cerebrovascular diseases have emerged as the second most important cause of mortality worldwide, from this principle we observe the importance of this study. Recently, as a solution form, stents have become a major treatment option for difficult and not feasible cerebral aneurysms single winding. Intracranial stents serve as a bridge to the neo-endothelialization by providing a reduction in blood flow into the aneurysm. The use of stents for treatment should be seriously analyzed according to their feasibility, the knowledge of the professional about their brands, features and deployment techniques, and theoretical part of the professional needs to have dexterity to the application of an intracranial stent. Conclusions: This review raises an awareness of this subject, starts from the concept of cerebrovascular disease and aneurysms as well as the genesis of the stents, progressing to elucidate all product brands and specific characteristics of each, ending with its applicability, as well as making clear the purpose and mechanism of stents.

  10. Microbial biosurfactants and biodegradation.

    Science.gov (United States)

    Ward, Owen P

    2010-01-01

    Microbial biosurfactants are amphipathic molecules having typical molecular weights of 500-1500 Da, made up of peptides, saccharides or lipids or their combinations. In biodegradation processes they mediate solubilisation, mobilization and/or accession of hydrophobic substrates to microbes. They may be located on the cell surface or be secreted into the extracellular medium and they facilitate uptake of hydrophobic molecules through direct cellular contact with hydrophobic solids or droplets or through micellarisation. They are also involved in cell physiological processes such as biofilm formation and detachment, and in diverse biofilm associated processes such as wastewater treatment and microbial pathogenesis. The protection of contaminants in biosurfactants micelles may also inhibit uptake of contaminants by microbes. In bioremediation processes biosurfactants may facilitate release of contaminants from soil, but soils also tend to bind surfactants strongly which makes their role in contaminant desorption more complex. A greater understanding of the underlying roles played by biosurfactants in microbial physiology and in biodegradative processes is developing through advances in cell and molecular biology.

  11. A COMPARATIVE STUDY OF PERCUTANEOUS NEPHROSTOMY VERSUS DJ STENTING IN INFECTIVE HYDRONEPHROSIS IN CALCULOUS DISEASE

    Directory of Open Access Journals (Sweden)

    Rammohan

    2015-02-01

    Full Text Available AIMS AND OBJECTIVE: To compare the outcome of percutaneous nephrostomy versus double J ureteral stenting in the management infective hydronephrosis in calculous disease. MATERIALS AND METHODS: From October 2012 to January 2014,40 patients of age 25 - 65 years with obstructing ureteral or renal pelvic stones with clinical signs of infection were underwent decompression by double J stenting(20 patients or percutaneous nephrostomy (20 patients in this study. Patients with single calculus of size less than or equal to 15mm with fever and white blood count (WBC of 14000/ mm 3 or greater were included in this study. Calculus size greater than 15 mm, patients with bilateral or multiple calculi, pregnancy, ureteral or urethral stricture disease, uncorrected coagulopathy, Patients with solitary kidney were excluded from the study. Outcome parameters included time to achieve normal temperature and WBC of 11000 /mm 3 or less, and resolution of pyuria if present were analyzed in both group of patients. RESULTS: Majority of the patients were between 25 to 65 years of age with male to female ratio was2.12:2.87.The most common location of stone was at distal ureter in either group. There was no significant difference between pre procedural WBC count, maximum temperature and stone size in either group. Procedura land fluoroscopy times were significantly shorter for double j stenting (30.95±6.02 and5.3±3.2 compared with percutaneous nephrostomy (35.9± 5.4 and7.2± 4.2. During drainage the appearance of the urine was grossly purulent in 5 patients (12.5%, turbid in 19 (47.5% and clear in 16 (40%. Overall urine cultures and blood cultures were positive in 50 and 12.5% of patients, respectively. Urine cultures were positive in 60% of the percutaneous nephrostomy compared with 40% of the double j stenting group (p not significant. There was no significant difference in time to clinical improvement (T ime to normal WBC and temperature and time for purulent drain

  12. Targeting In-Stent-Stenosis with RGD- and CXCL1-Coated Mini-Stents in Mice.

    Science.gov (United States)

    Simsekyilmaz, Sakine; Liehn, Elisa A; Weinandy, Stefan; Schreiber, Fabian; Megens, Remco T A; Theelen, Wendy; Smeets, Ralf; Jockenhövel, Stefan; Gries, Thomas; Möller, Martin; Klee, Doris; Weber, Christian; Zernecke, Alma

    2016-01-01

    Atherosclerotic lesions that critically narrow the artery can necessitate an angioplasty and stent implantation. Long-term therapeutic effects, however, are limited by excessive arterial remodeling. We here employed a miniaturized nitinol-stent coated with star-shaped polyethylenglycole (star-PEG), and evaluated its bio-functionalization with RGD and CXCL1 for improving in-stent stenosis after implantation into carotid arteries of mice. Nitinol foils or stents (bare metal) were coated with star-PEG, and bio-functionalized with RGD, or RGD/CXCL1. Cell adhesion to star-PEG-coated nitinol foils was unaltered or reduced, whereas bio-functionalization with RGD but foremost RGD/CXCL1 increased adhesion of early angiogenic outgrowth cells (EOCs) and endothelial cells but not smooth muscle cells when compared with bare metal foils. Stimulation of cells with RGD/CXCL1 furthermore increased the proliferation of EOCs. In vivo, bio-functionalization with RGD/CXCL1 significantly reduced neointima formation and thrombus formation, and increased re-endothelialization in apoE-/- carotid arteries compared with bare-metal nitinol stents, star-PEG-coated stents, and stents bio-functionalized with RGD only. Bio-functionalization of star-PEG-coated nitinol-stents with RGD/CXCL1 reduced in-stent neointima formation. By supporting the adhesion and proliferation of endothelial progenitor cells, RGD/CXCL1 coating of stents may help to accelerate endothelial repair after stent implantation, and thus may harbor the potential to limit the complication of in-stent restenosis in clinical approaches.

  13. Targeting In-Stent-Stenosis with RGD- and CXCL1-Coated Mini-Stents in Mice.

    Directory of Open Access Journals (Sweden)

    Sakine Simsekyilmaz

    Full Text Available Atherosclerotic lesions that critically narrow the artery can necessitate an angioplasty and stent implantation. Long-term therapeutic effects, however, are limited by excessive arterial remodeling. We here employed a miniaturized nitinol-stent coated with star-shaped polyethylenglycole (star-PEG, and evaluated its bio-functionalization with RGD and CXCL1 for improving in-stent stenosis after implantation into carotid arteries of mice. Nitinol foils or stents (bare metal were coated with star-PEG, and bio-functionalized with RGD, or RGD/CXCL1. Cell adhesion to star-PEG-coated nitinol foils was unaltered or reduced, whereas bio-functionalization with RGD but foremost RGD/CXCL1 increased adhesion of early angiogenic outgrowth cells (EOCs and endothelial cells but not smooth muscle cells when compared with bare metal foils. Stimulation of cells with RGD/CXCL1 furthermore increased the proliferation of EOCs. In vivo, bio-functionalization with RGD/CXCL1 significantly reduced neointima formation and thrombus formation, and increased re-endothelialization in apoE-/- carotid arteries compared with bare-metal nitinol stents, star-PEG-coated stents, and stents bio-functionalized with RGD only. Bio-functionalization of star-PEG-coated nitinol-stents with RGD/CXCL1 reduced in-stent neointima formation. By supporting the adhesion and proliferation of endothelial progenitor cells, RGD/CXCL1 coating of stents may help to accelerate endothelial repair after stent implantation, and thus may harbor the potential to limit the complication of in-stent restenosis in clinical approaches.

  14. The current status of stenting pathobiology.

    Science.gov (United States)

    Fleser, A; Leclerc, G

    1997-01-01

    Stents permanently maximize the arterial lumen following percutaneous transluminal coronary angioplasty (PTCA) at the cost of a vascular injury caused by the deployment of the prosthesis. Even though clinical trials show progressive reduction of restenosis and thrombosis rates in implanted coronary stents, these two events continue to represent a potential limitation to their clinical use. This review is focused on the arterial pathobiology related to the use of permanent and temporary stents. © 1997, Elsevier Science Inc. (Trends Cardiovasc Med 1997;7:24-28).

  15. Efficacy and safety of drug-eluting stent implantation for the treatment of in-stent restenosis occurring within bare-metal stent and drug-eluting stent*

    OpenAIRE

    Ge, Heng; Zhang, Qing; Zhou, Wei; He, Qing; Han, Zhi-hua; He, Ben

    2010-01-01

    Objective: Although drug-eluting stent (DES) implantation is the primary treatment modality for bare-metal stent (BMS) in-stent restenosis (ISR), little is known about the efficacy and safety profile of DES in the treatment of DES-ISR. The goal of this study was to compare the clinical outcomes following DES treatment for BMS-ISR and DES-ISR. Methods: Rates of major adverse cardiac events (MACE) were compared in 97 consecutive patients who underwent DES implantation for the treatment of ISR (...

  16. Trajectory surgical guide stent for implant placement.

    Science.gov (United States)

    Adrian, E D; Ivanhoe, J R; Krantz, W A

    1992-05-01

    This article describes a new implant placement surgical guide that gives both implant location and trajectory to the surgeon. Radiopaque markers are placed on diagnostic dentures and a lateral cephalometric radiograph is made that shows the osseous anatomy at the symphysis and the anterior tooth location. The ideal implant location and trajectory data are transferred to a surgical stent that programs the angle and location of the fixtures at time of surgery. The stent has the additional benefit of acting as an occlusion rim, a mouth prop, and tongue retractor. Use of this stent has resulted in consistently programming the placement of implant fixtures that are prosthodontically ideal.

  17. Carotid Stent Fracture from Stylocarotid Syndrome

    Science.gov (United States)

    Hooker, Jeffrey D; Joyner, David A; Farley, Edward P; Khan, Majid

    2016-01-01

    Eagle syndrome is a rare condition resulting from elongation of the temporal styloid process or calcification of its associated stylohyoid ligaments. Although usually presenting with pain or odynophagia, Eagle syndrome has been reported to cause a multitude of neurologic symptoms or vascular complications, some of which can be life-threatening. We present a case in which an endovascularly placed internal carotid artery stent in close proximity to a calcified stylohyoid ligament resulted in stent fracture with subsequent stent and vessel occlusion. We review and discuss the presentation, diagnosis, etiology, complications and treatment options of the syndrome.

  18. Forgotten CBD stent (102 months) with stone-stent complex: A case report.

    Science.gov (United States)

    Barai, Varsha; Hedawoo, Jagadish; Changole, Sanjay

    2017-01-01

    Choledocholithiasis is presence of stone in Common bile duct (CBD) which can be treated by endoscopy or surgery [1]. Retained foreign bodies like stents forms a nidus for stone formation resulting in pain, fever, jaundice. 60 years female patient admitted in surgery ward with features of cholangitis with computed tomography showing cholangitic abscess with dilated common bile duct and sludge around stent in situ. Stone was found at proximal end of stent during surgery. Stents may remain without complications or may migrate, and rarely form nidus for stone formation. If kept for long time they lead to bacterial proliferation, biofilm formation and precipitation of calcium bilirubinate presenting as fever, pain, jaundice. Stent-stone complex can be treated endoscopically and surgically [6,7]. As stent can cause stone formation, infection and other complications, timely removal of stent should advised. III-effects of stent in-situ should be explained, record should be maintained [8] and patient should be advised regular follow up and stent removal after 6 weeks. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  19. Paraffin processing of stented arteries using a postfixation dissolution of metallic and polymeric stents.

    Science.gov (United States)

    Fishbein, Ilia; Welch, Tre; Guerrero, David T; Alferiev, Ivan S; Adamo, Richard F; Chorny, Michael; Gupte, Rohit K; Tang, Yanqing; Levy, Robert J

    Studying the morphology of the arterial response to endovascular stent implantation requires embedding the explanted stented artery in rigid materials such as poly(methyl methacrylate) to enable sectioning through both the in situ stent and the arterial wall, thus maintaining the proper anatomic relationships. This is a laborious, time-consuming process. Moreover, the technical quality of stained plastic sections is typically suboptimal and, in some cases, precludes immunohistochemical analysis. Here we describe a novel technique for dissolution of metallic and plastic stents that is compatible with subsequent embedding of "destented" arteries in paraffin, fine sectioning, major staining protocols, and immunohistochemistry.

  20. Development and assessment of 316LVM cardiovascular stents

    Energy Technology Data Exchange (ETDEWEB)

    Raval, Ankur [Research and Development Division, Sahajanand Medical Technologies, Surat 395003 (India)]. E-mail: ankur.med@sahmed.com; Choubey, Animesh [Research and Development Division, Sahajanand Medical Technologies, Surat 395003 (India); Engineer, Chhaya [Research and Development Division, Sahajanand Medical Technologies, Surat 395003 (India); Kothwala, Devesh [Research and Development Division, Sahajanand Medical Technologies, Surat 395003 (India)

    2004-11-25

    One of the most common causes for heart failure is vasoconstriction. The medical procedure for alleviating vasoconstriction, angioplasty, calls for intracoronary stents. And the manufacture of intracoronary stents demands absolutely unmatched precision. Current study investigates CNC controlled pulsed Nd:YAG (neodymium:yttrium aluminium garnet) laser for cutting complex geometry of a stent on 316LVM tubings. It has been shown that surface quality of cardiovascular stents has a significant influence on biocompatibility. Therefore, optimal method and parameters for acid pickling of these slotted tube laser cut stents were explored, as a pretreatment for electropolishing. Pickling was necessary prior to electropolishing for removing the oxide films covering the stent surface. An optimal condition for electrochemical polishing could also be established and it caused a smooth stent surface. Passivation of these electropolished stents was done. Furthermore, materials characterization of stents was performed by means of composition and microstructural analysis.