WorldWideScience

Sample records for blood vessel prosthesis implantation

  1. An artificial blood vessel implanted three-dimensional microsystem for modeling transvascular migration of tumor cells.

    Science.gov (United States)

    Wang, Xue-Ying; Pei, Ying; Xie, Min; Jin, Zi-He; Xiao, Ya-Shi; Wang, Yang; Zhang, Li-Na; Li, Yan; Huang, Wei-Hua

    2015-02-21

    Reproducing a tumor microenvironment consisting of blood vessels and tumor cells for modeling tumor invasion in vitro is particularly challenging. Here, we report an artificial blood vessel implanted 3D microfluidic system for reproducing transvascular migration of tumor cells. The transparent, porous and elastic artificial blood vessels are obtained by constructing polysaccharide cellulose-based microtubes using a chitosan sacrificial template, and possess excellent cytocompatibility, permeability, and mechanical characteristics. The artificial blood vessels are then fully implanted into the collagen matrix to reconstruct the 3D microsystem for modeling transvascular migration of tumor cells. Well-defined simulated vascular lumens were obtained by proliferation of the human umbilical vein endothelial cells (HUVECs) lining the artificial blood vessels, which enables us to reproduce structures and functions of blood vessels and replicate various hemodynamic parameters. Based on this model, the adhesion and transvascular migration of tumor cells across the artificial blood vessel have been well reproduced.

  2. Penile prosthesis implantation: past, present and future.

    Science.gov (United States)

    Simmons, M; Montague, D K

    2008-01-01

    Penile prosthesis implantation is the oldest effective treatment for erectile dysfunction. This review examines the past, present and future of penile prosthesis implantation. Advances in prosthetic design and implantation techniques have resulted today in devices that produce nearly normal flaccid and erect states, and have remarkable freedom from mechanical failure. The future of prosthetic design holds promises for even more improvements.

  3. Microsurgical treatment of infected extremities after blood vessel prosthesis%人工血管移植感染的显微外科治疗

    Institute of Scientific and Technical Information of China (English)

    左中男; 于绍斌; 左熙; 靳高峰; 杜永军; 杜学亮; 黎德规

    2009-01-01

    目的 报道人工血管移植感染显微外科治疗的临床疗效. 方法 从1998年1月至2008年12月,应用健侧肢体血管桥式交叉供血营养患肢治疗人工血管移植感染8例,其中股动、静脉4例.腘动、静脉2例,腋动、静脉2例. 结果 术后随访3年,所有肢体血液供应良好,肢体外形及功能恢复. 结论 应用健侧肢体血管桥式交叉供血营养患肢可有效恢复人工血管移植后感染肢体的血液供应,降低截肢率.%Objective To report the clinical effects of microsurgery in treatment of infected extremities after blood vessel prosthesis were transplanted.Methods From Jan.1998 to Dec.2008,8 cases of major vascular injuries in extremities were blood-supplied by cross bridge vascular anastomosis from uninjured extremities,including 4 cases of femoral artery and vein,2 cases of popliteal artery and vein,and 2 cases of brachial artery and vein. Results After 3 years of follow-up,blood circulation of infected extremities were reestablished in each of 8 cases,as well as function and appearance recovered.Conclusion The procedure of cross bridge vascular anastomosis from uninjured extremities may efficiently restitute the blood supply of the infected extremities after blood vessel prosthesis were transplanted,and decrease the rate of amputation.

  4. 21 CFR 874.3695 - Mandibular implant facial prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mandibular implant facial prosthesis. 874.3695... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3695 Mandibular implant facial prosthesis. (a) Identification. A mandibular implant facial prosthesis is a device that...

  5. Investigation of source-detector separation optimization for an implantable perfusion and oxygenation sensor for liver blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Justin S [ORNL; Akl, Tony [Texas A& M University; Cote, Gerard L. [Texas A& M University; Wilson, Mark A. [University of Pittsburgh School of Medicine, Pittsburgh PA; Ericson, Milton Nance [ORNL

    2011-01-01

    An implanted system is being developed to monitor transplanted liver health during the critical 7-10 day period posttransplantation. The unit will monitor organ perfusion and oxygen consumption using optically-based probes placed on both the inflow and outflow blood vessels, and on the liver parenchymal surface. Sensing probes are based on a 3- wavelength LED source and a photodiode detector. Sample diffuse reflectance is measured at 735, 805, and 940 nm. To ascertain optimal source-to-photodetector spacing for perfusion measurement in blood vessels, an ex vivo study was conducted. In this work, a dye mixture simulating 80% blood oxygen saturation was developed and perfused through excised porcine arteries while collecting data for various preset probe source-to-photodetector spacings. The results from this study demonstrate a decrease in the optical signal with decreasing LED drive current and a reduction in perfusion index signal with increasing probe spacing. They also reveal a 2- to 4-mm optimal range for blood vessel perfusion probe source-to-photodetector spacing that allows for sufficient perfusion signal modulation depth with maximized signal to noise ratio (SNR). These findings are currently being applied to guide electronic configuration and probe placement for in vivo liver perfusion porcine model studies.

  6. Clinical Outcomes of Penile Prosthesis Implantation Surgery

    Directory of Open Access Journals (Sweden)

    Onur Dede

    2016-06-01

    Full Text Available Objective: We aimed to evaluating the outcomes of in­flatable penile prosthesis implantations and partner sat­isfaction. Methods: Data of 52 patients who underwent penile prosthesis implantation in single center between May 2010 and December 2015 were retrospectively analyzed. Types of prosthesis, complication and satisfaction rates of patients were recorded by EDITS (Erectile Dysfunction Inventory of Treatment Satisfaction questionnaire was used. Results: The mean age was 49.2±14.7 years for patients. The mean follow-up durations for 34.3±12.5 months. The mean hospital stay was 3.84±1.52 days. Evaluating of the couples satisfaction revealed that 44 (84% of the patient were very satisfied. There was not any complication and no patient need to underwent revision surgery. Conclusion: Inflatable penile prosthesis implants, with high levels of treatment success, patient and partner sat­isfaction, are effective and safe options for treatment of organic erectile dysfunction with acceptable complication and revision rates.

  7. Cochlear implantation: a biomechanical prosthesis for hearing loss.

    Science.gov (United States)

    Yawn, Robert; Hunter, Jacob B; Sweeney, Alex D; Bennett, Marc L

    2015-01-01

    Cochlear implants are a medical prosthesis used to treat sensorineural deafness, and one of the greatest advances in modern medicine. The following article is an overview of cochlear implant technology. The history of cochlear implantation and the development of modern implant technology will be discussed, as well as current surgical techniques. Research regarding expansion of candidacy, hearing preservation cochlear implantation, and implantation for unilateral deafness are described. Lastly, innovative technology is discussed, including the hybrid cochlear implant and the totally implantable cochlear implant.

  8. Ischemic Gangrene of the Glans following Penile Prosthesis Implantation

    OpenAIRE

    Borja García Gómez; Javier Romero Otero; Laura Díez Sicilia; Estibaliz Jiménez Alcaide; Eduardo García-Cruz; Alfredo Rodríguez Antolín

    2013-01-01

    The development of ischemic gangrene of the penis following implantation of prosthesis is unusual, and very few cases are available in the literature. As a result, no established treatment protocol is available. We report our experience within a case of gangrene of the glans following implantation of a three-component prosthesis. We present a 53-year-old male, smoker with diabetes and hypercholesterolemia, who underwent surgery for the insertion of a penile prosthesis with 3 components to cor...

  9. Blood Vessel Tension Tester

    Science.gov (United States)

    1978-01-01

    In the photo, a medical researcher is using a specially designed laboratory apparatus for measuring blood vessel tension. It was designed by Langley Research Center as a service to researchers of Norfolk General Hospital and Eastern Virginia Medical School, Norfolk, Virginia. The investigators are studying how vascular smooth muscle-muscle in the walls of blood vessels-reacts to various stimulants, such as coffee, tea, alcohol or drugs. They sought help from Langley Research Center in devising a method of measuring the tension in blood vessel segments subjected to various stimuli. The task was complicated by the extremely small size of the specimens to be tested, blood vessel "loops" resembling small rubber bands, some only half a millimeter in diameter. Langley's Instrumentation Development Section responded with a miniaturized system whose key components are a "micropositioner" for stretching a length of blood vessel and a strain gage for measuring the smooth muscle tension developed. The micropositioner is a two-pronged holder. The loop of Mood vessel is hooked over the prongs and it is stretched by increasing the distance between the prongs in minute increments, fractions of a millimeter. At each increase, the tension developed is carefully measured. In some experiments, the holder and specimen are lowered into the test tubes shown, which contain a saline solution simulating body fluid; the effect of the compound on developed tension is then measured. The device has functioned well and the investigators say it has saved several months research time.

  10. Split-Framework in Mandibular Implant-Supported Prosthesis

    Directory of Open Access Journals (Sweden)

    Danny Omar Mendoza Marin

    2015-01-01

    Full Text Available During oral rehabilitation of an edentulous patient with an implant-supported prosthesis, mandibular flexure must be considered an important biomechanical factor when planning the metal framework design, especially if implants are installed posterior to the interforaminal region. When an edentulous mandible is restored with a fixed implant-supported prosthesis connected by a fixed full-arch framework, mandibular flexure may cause needless stress in the overall restorative system and lead to screw loosening, poor fit of prosthesis, loss of the posterior implant, and patient’s discomfort due to deformation properties of the mandible during functional movements. The use of a split-framework could decrease the stress with a precise and passive fit on the implants and restore a more natural functional condition of the mandible, helping in the longevity of the prosthesis. Therefore, the present clinical report describes the oral rehabilitation of an edentulous patient by a mandibular fixed implant-supported prosthesis with a split-framework to compensate for mandibular flexure. Clinical Significance. The present clinical report shows that the use of a split-framework reduced the risk of loss of the posterior implants or screws loosening with acceptable patient comfort over the period of a year. The split-framework might have compensated for the mandibular flexure during functional activities.

  11. 多普勒血流检查评价下肢动脉旁路术流出道的价值%Doppler ultrasound assess outlets in lower extremity arterias treated by blood vessel prosthesis

    Institute of Scientific and Technical Information of China (English)

    周晗; 吴庆华; 陈忠; 罗小云; 张煜亚; 杨培

    2009-01-01

    目的 探讨多普勒血流检查中节段性压力比值对评估下肢动脉硬化闭塞症患者远端动脉流出道的应用价值,以对人工血管旁路术适应证的选择提供参考.方法 回顾性分析北京安贞医院血管外科1998--2005年收治的166例下肢动脉硬化闭塞症行人工血管旁路术患者的资料,分析流出道节段性压力比值差值等与人工血管通畅率相关的因素,比较人工血管通畅组与阻塞组术前流出道节段性压力比值差值的差异.结果 流出道的节段性压力比值差值是影响人工血管术后通畅率危险程度最高的相关因素之一.人工血管通畅组与阻塞组流出道节段性压力比值差值分别为0.12±0.09和0.24±0.14,两组间比较,差异有统计学意义(P=0.001).人工血管通畅组流出道的节段性压力比值差值的95%可信区间为(0,0.27).结论 多普勒血流检查是一种量化的检查方法,节段性压力比值差值的区间范围可以作为临床上评价流出道及预测手术通畅率的参考.%Objective To explore segmantal blood pressure ratio in Doppler ultrasound in the evaluation of distal outlets in lower extremity atherosclerosis ocllusion patients undergoing blood vessel prosthesis and provide references to surgical indications. Methods A review research was made on 166 lower extremity atherosclerosis ocllusion patients receiving blood vessel prosthesis therapy in Anzhen hospital in 1998--2005. We analyzed related factors including segmantal blood pressure ratio to potency rate, evaluated the difference of segmantal blood pressure ratio between groups in which the blood vessel prosthesis was patent and that it was not. Results The difference of segmantal blood pressure ratio of outlet is one of the highest risk among risk factors. The Mean ± SDs of segmantal blood pressure ratio of outlet in patent and obstructed groups were 0. 12±0. 09 and 0. 24±0. 14 respectively. The difference of segmantal blood pressure

  12. 21 CFR 872.3970 - Interarticular disc prosthesis (interpositional implant).

    Science.gov (United States)

    2010-04-01

    ... implant). 872.3970 Section 872.3970 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3970 Interarticular disc prosthesis (interpositional implant). (a) Identification. An interarticular disc...

  13. Amputation and prosthesis implantation shape body and peripersonal space representations.

    Science.gov (United States)

    Canzoneri, Elisa; Marzolla, Marilena; Amoresano, Amedeo; Verni, Gennaro; Serino, Andrea

    2013-10-03

    Little is known about whether and how multimodal representations of the body (BRs) and of the space around the body (Peripersonal Space, PPS) adapt to amputation and prosthesis implantation. In order to investigate this issue, we tested BR in a group of upper limb amputees by means of a tactile distance perception task and PPS by means of an audio-tactile interaction task. Subjects performed the tasks with stimulation either on the healthy limb or the stump of the amputated limb, while wearing or not wearing their prosthesis. When patients performed the tasks on the amputated limb, without the prosthesis, the perception of arm length shrank, with a concurrent shift of PPS boundaries towards the stump. Conversely, wearing the prosthesis increased the perceived length of the stump and extended the PPS boundaries so as to include the prosthetic hand, such that the prosthesis partially replaced the missing limb.

  14. Transcatheter aortic valve prosthesis surgically replaced 4 months after implantation

    DEFF Research Database (Denmark)

    Thyregod, Hans Gustav; Lund, Jens Teglgaard; Engstrøm, Thomas;

    2010-01-01

    Transcatheter aortic valve implantation is a new and rapidly evolving treatment option for high-risk surgical patients with degenerative aortic valve stenosis. Long-term results with these new valve prostheses are lacking, and potential valve dysfunction and failure would require valve replacement....... We report the first case of surgical valve replacement in a patient with a dysfunctional transcatheter-implanted aortic valve prosthesis 4 months after implantation....

  15. Ischemic Gangrene of the Glans following Penile Prosthesis Implantation

    Science.gov (United States)

    García Gómez, Borja; Romero Otero, Javier; Díez Sicilia, Laura; Jiménez Alcaide, Estibaliz; García-Cruz, Eduardo; Rodríguez Antolín, Alfredo

    2013-01-01

    The development of ischemic gangrene of the penis following implantation of prosthesis is unusual, and very few cases are available in the literature. As a result, no established treatment protocol is available. We report our experience within a case of gangrene of the glans following implantation of a three-component prosthesis. We present a 53-year-old male, smoker with diabetes and hypercholesterolemia, who underwent surgery for the insertion of a penile prosthesis with 3 components to correct his erectile dysfunction and severe Peyronie's disease. The procedure was carried out without incidents. During the postoperative period, the patient began to complain from penile and perineal pain. He developed avascular necrosis of the glans. The necrosed area was excised. Four weeks later, he developed fever and perineal pain arriving to the emergency room with the prosthesis extruding through the glans. He had emergency surgery to remove the prosthesis plus surgical lavage and was prescribed broad-spectrum antibiotic therapy. Four weeks later, the penis was completely revascularized and reepithelialized. Ischemic gangrene following penile prosthesis implantation takes place in patients with poor peripheral vascularisation. Diabetes mellitus has been the common denominator to all of the reported cases. PMID:23956919

  16. Ischemic Gangrene of the Glans following Penile Prosthesis Implantation

    Directory of Open Access Journals (Sweden)

    Borja García Gómez

    2013-01-01

    Full Text Available The development of ischemic gangrene of the penis following implantation of prosthesis is unusual, and very few cases are available in the literature. As a result, no established treatment protocol is available. We report our experience within a case of gangrene of the glans following implantation of a three-component prosthesis. We present a 53-year-old male, smoker with diabetes and hypercholesterolemia, who underwent surgery for the insertion of a penile prosthesis with 3 components to correct his erectile dysfunction and severe Peyronie's disease. The procedure was carried out without incidents. During the postoperative period, the patient began to complain from penile and perineal pain. He developed avascular necrosis of the glans. The necrosed area was excised. Four weeks later, he developed fever and perineal pain arriving to the emergency room with the prosthesis extruding through the glans. He had emergency surgery to remove the prosthesis plus surgical lavage and was prescribed broad-spectrum antibiotic therapy. Four weeks later, the penis was completely revascularized and reepithelialized. Ischemic gangrene following penile prosthesis implantation takes place in patients with poor peripheral vascularisation. Diabetes mellitus has been the common denominator to all of the reported cases.

  17. Penile prosthesis implantation in a transsexual neophallus

    Institute of Scientific and Technical Information of China (English)

    Hui-MengTAN

    2000-01-01

    Reconstruction surgery for a female to male transsexual usually involves mastectomy, hysterectomy and creating an aesthetically appealing neophallus. We have successfully inserted an inflatable prosthesis using the AMS CX prosthesis in a 45 year old transsexual, who had a large bulky neophallus constructed from the anterior abdominal subcutaneous fat, about 9 years ago. The single cylinder CX prosthesis was well anchored to the symphysis pubis using a dacron windsock tubing, the activation pump was placed in the dependent pouch of the right labium and the reservior in the usual perivesical space. The patient subsequently had debulking procedure using liposuction to create a more aesthetic and functional phallus. To date, the inflatable neophallus prosthesis is functioning well. (Asian J Androl 2000 Dec;2:304-306)

  18. Penile prosthesis implantation in the era of medical treatment for erectile dysfunction.

    Science.gov (United States)

    Montague, Drogo K

    2011-05-01

    Penile prosthesis implantation, the oldest of the modern treatments for erectile dysfunction (ED), still plays an important role despite the advent of less invasive alternatives. For some men with ED, penile prosthesis implantation is the only effective or acceptable treatment. Penile prosthesis implantation remains a viable option in the contemporary management of ED as evidenced by annual penile prosthesis implantation cases in the United States rising from 17,540 in 2000 to 22,420 in 2009. Improvements in prosthesis design and implantation techniques have resulted in significant increases in device survival and patient satisfaction.

  19. Fabrication of an Implant-Supported Fixed Interim Prosthesis Using a Duplicate Denture: An Alternative Technique.

    Science.gov (United States)

    Al-Thobity, Ahmad M

    2016-06-22

    The fabrication of an implant-supported fixed complete denture prosthesis involves multiple clinical and laboratory steps. One of the main steps is to provide the patient with an interim fixed prosthesis to evaluate the patient's esthetic and functional needs as well as to enhance the patient's psychology before proceeding to the definitive prosthesis. Different techniques for fabricating interim prostheses have been described in the literature. This report describes an alternative technique that uses a duplicate denture made of self-curing acrylic resin to fabricate an implant-supported fixed interim prosthesis. The interim prosthesis was later used as a blueprint for the definitive implant-supported hybrid prosthesis.

  20. Immediate placement and loading of implants in anterior maxilla using an altered screw-retained implant fixed prosthesis

    Directory of Open Access Journals (Sweden)

    Baig Mirza

    2010-01-01

    Full Text Available This article describes the immediate placement and loading of implants in the aesthetic zone using an implant-retained, fixed prosthesis with a modified design. One section of the implant prosthesis has cemented crowns and the other section is the conventional screw-retained. This combined approach significantly offsets the unsuitable implant position, alignment or angulation, while ensuring the easy retrievability, repair and maintenance of the prosthesis at the same time.

  1. Flap repair for vascular prosthesis exposure after artificial blood vessel bypass surgery for critical limb ischemia%皮瓣重建修复下肢动脉旁路移植术后人工血管外露

    Institute of Scientific and Technical Information of China (English)

    吴巍巍; 吴昊; 曾昂; 白明; 曾嵘; 陈宇; 刘昌伟

    2013-01-01

    Objective To investigate the effectiveness of flap repair for vascular prosthesis exposure after the artificial blood vessel bypass surgery for critical limb ischemia.Methods From August 2007 to December 2011,bypass surgery with vascular prosthetic grafts were performed in 192 patients with critical limb ischemia.Five patients among them (2.6%) suffered from vascular prosthesis exposure 6 to 13 days after the previous surgery,including 4 males and 1 female,with a median age of 68 years (arranged from 52 to 81 years).The surgical managements included surgical debridement and local flap or transferred muscle-cutaneous flap repair to preserve the prosthetic vascular grafts.Three patients underwent Z-plasty with local flap repair,while 2 patients underwent transferred rectus abdominis or rectus femoris muscle flap repair of the wounds.Results After the surgery,prosthetic vascular graft was successfully preserved in 4 of the 5 cases with first intention healing.At a median follow-up of 38 months (arranged from 5 to 57 months),all the 4 limbs were salvaged with patent of the prosthetic grafts.One flap failed to heal and the prosthetic graft had to be removed due to infection and hemorrhage.An above-knee-amputation was performed due to severe limb ischemia.Conclusions The vascular prosthesis exposure is often a disaster after artificial blood vessel bypass surgery for critical limb ischemia.Local flap or transferred muscle-cutaneous flap repair is an effective surgical management to salvage the exposed graft and the affected limb.%目的 探讨皮瓣重建技术修复因重症下肢缺血行人工血管旁路移植术后人工血管外露的可行性.方法 回顾性分析2007年8月至201 1年12月诊治的192例下肢人工血管旁路移植术后患者,其中5例(2.6%)在前次术后6~13d发生人工血管外露,包括男性4例,女性1例,年龄52~81岁,中位年龄68岁.外科处理主要包括局部清创及保留移植物的任意皮

  2. Heterotopic ossification associated with myelopathy following cervical disc prosthesis implantation.

    Science.gov (United States)

    Wenger, Markus; Markwalder, Thomas-Marc

    2016-04-01

    This case report presents a 37-year-old man with clinical signs of myelopathy almost 9 years after implantation of a Bryan disc prosthesis (Medtronic Sofamor Danek, Memphis, TN, USA) for C5/C6 soft disc herniation. As demonstrated on MRI and CT scan, spinal cord compression was caused by bony spurs due to heterotopic ossification posterior to the still moving prosthesis. The device, as well as the ectopic bone deposits, had to be removed because of myelopathy and its imminent aggravation. Conversion to anterior spondylodesis was performed.

  3. Intraoral framework pick-up technique to improve fit of a metal-resin implant prosthesis

    Directory of Open Access Journals (Sweden)

    Mirza Rustum Baig

    2012-01-01

    Full Text Available The achievement of passive fit is an important prerequisite for the prevention of complications in full-arch screw-retained implant prosthesis. With cemented prosthesis, the cementation compensates for the discrepancies in the cast framework, but the lack of retrievability seems undesirable. The aim of this paper is to propose a modified screw-retained prosthesis design for complete arch implant fixed rehabilitation. A technique for the fabrication of a full-arch metal-resin implant-supported screw-retained prosthesis is described. Cementation of the framework to the abutments intraorally improves the passivity of fit of the prosthesis on the implants. Maintenance of screw-access channels in the final prosthesis ensures retrievability. The metal-resin design allows for easy repair and maintenance. The prosthesis is cost-effective compared to conventional options and can be employed as a viable treatment alternative when considering metal-acrylic resin complete arch fixed prosthesis.

  4. Modified cementless total coxofemoral prosthesis: development, implantation and clinical evaluation

    Directory of Open Access Journals (Sweden)

    S.A. Arias

    2013-12-01

    Full Text Available The aim of this study was to modify canine coxofemoral prostheses and the clinical evaluation of the implantation. Fifteen canine hips and femora of cadavers were used in order to study the surface points of modification in prostheses and develop a perforation guide. Femoral stems and acetabular components were perforated and coated with biphasic calcium phosphate layer. Twelve young adult male mongrel dogs were implanted with coxofemoral prostheses. Six were operated upon and implanted with cemented canine modular hip prostheses, establishing the control group. The remaining six were implanted with a novel design of cementless porous tricalcic phosphate-hydroxyapatite coated hip prostheses. Clinical and orthopedic performance, complications, and thigh muscular hypotrophy were assessed up to the 120th post-operatory day. After 120 days, animals with cementless prostheses had similar clinical and orthopedic performance compared to the cemented group despite the increased pain thigh hypotrophy. Animals that underwent cementless hip prosthesis evidenced more pain, compared to animals with cemented hip prosthesis that required longer recuperation time. No luxations, two fractures and two isquiatic neurapraxies were identified in the course of the study. Using both the cemented and the bioactive coated cementless model were suitable to dogs, showing clinical satisfactory results. Osseointegration and biological fixation were observed in the animals with the modified cementless hip prosthesis.

  5. Maxillary cement retained implant supported monolithic zirconia prosthesis in a full mouth rehabilitation: a clinical report

    OpenAIRE

    Sadid-Zadeh, Ramtin; Liu, Perng-Ru; Aponte-Wesson, Ruth; O'Neal, Sandra J

    2013-01-01

    This clinical report presents the reconstruction of a maxillary arch with a cement retained implant supported fixed prosthesis using a monolithic zirconia generated by CAD/CAM system on eight osseointegrated implants. The prosthesis was copy milled from an interim prosthesis minimizing occlusal adjustments on the definitive prosthesis at the time of delivery. Monolithic zirconia provides high esthetics and reduces the number of metal alloys used in the oral cavity.

  6. Maxillary cement retained implant supported monolithic zirconia prosthesis in a full mouth rehabilitation: a clinical report.

    Science.gov (United States)

    Sadid-Zadeh, Ramtin; Liu, Perng-Ru; Aponte-Wesson, Ruth; O'Neal, Sandra J

    2013-05-01

    This clinical report presents the reconstruction of a maxillary arch with a cement retained implant supported fixed prosthesis using a monolithic zirconia generated by CAD/CAM system on eight osseointegrated implants. The prosthesis was copy milled from an interim prosthesis minimizing occlusal adjustments on the definitive prosthesis at the time of delivery. Monolithic zirconia provides high esthetics and reduces the number of metal alloys used in the oral cavity.

  7. A multiaxial force-sensing implantable tibial prosthesis.

    Science.gov (United States)

    Kirking, Bryan; Krevolin, Janet; Townsend, Christopher; Colwell, Clifford W; D'Lima, Darryl D

    2006-01-01

    Accurate in vivo measurement of tibiofemoral forces is important in total knee arthroplasty. These forces determine polyethylene stresses and cold-flow, stress distribution in the implant, and stress transfer to the underlying implant bone interface. Theoretic estimates of tibiofemoral forces have varied widely depending on the mathematical models used. The six degrees of freedom of motion, complex articular surface topography, changing joint-contact position, intra- and extra-articular ligaments, number of muscles crossing the knee joint, and the presence of the patellofemoral joint contribute to the difficulty in developing reliable models of the knee. A prototype instrumented total knee replacement tibial prosthesis was designed, manufactured, and tested. This prosthesis accurately measured all six components of tibial forces (R2>0.997). The prosthesis was also instrumented with an internal microtransmitter for wireless data transmission. Remote powering of the sealed implanted electronics was achieved using magnetic coil induction. This device can be used to validate existing models of the knee that estimate these forces or to develop more accurate models. In conjunction with kinematic data, accurate tibiofemoral force data may be used to design more effective knee-testing rigs and wear simulators. Additional uses are intraoperative measurement of forces to determine soft-tissue balancing and to evaluate the effects of rehabilitation, external bracing, and athletic activities, and activities of daily living.

  8. Intraoral framework pick-up technique to improve fit of a metal-resin implant prosthesis

    OpenAIRE

    Mirza Rustum Baig; Rajan Gunaseelan

    2012-01-01

    The achievement of passive fit is an important prerequisite for the prevention of complications in full-arch screw-retained implant prosthesis. With cemented prosthesis, the cementation compensates for the discrepancies in the cast framework, but the lack of retrievability seems undesirable. The aim of this paper is to propose a modified screw-retained prosthesis design for complete arch implant fixed rehabilitation. A technique for the fabrication of a full-arch metal-resin implant-supported...

  9. Blood vessels, circulation and blood pressure.

    Science.gov (United States)

    Hendry, Charles; Farley, Alistair; McLafferty, Ella

    This article, which forms part of the life sciences series, describes the vessels of the body's blood and lymphatic circulatory systems. Blood pressure and its regulatory systems are examined. The causes and management of hypertension are also explored. It is important that nurses and other healthcare professionals understand the various mechanisms involved in the regulation of blood pressure to prevent high blood pressure or ameliorate its damaging consequences.

  10. Rehabilitation of orbital defect with silicone orbital prosthesis retained by dental implants

    Science.gov (United States)

    Guttal, Satyabodh Shesharaj; Desai, Jhanvi; Kudva, Adarsh; Patil, Basavaraj R

    2016-01-01

    Orbital defects can result from cancer, birth anomalies, or trauma leading to an onslaught of problems in the function and psyche of the patient. These defects are restored by surgical reconstruction and followed by placement of orbital prosthesis for cosmetic makeup. The use of dental implants in retaining orbital prosthesis improves patient acceptance of the prosthesis owing to better retention and stability than conventional adhesive retained prosthesis. This case report describes a custom-made magnetic retentive assembly anchored by a dental implant which offers the orbital prosthesis the simplicity of self-alignment and ease of use. PMID:26953033

  11. Development of an implantable myoelectric sensor for advanced prosthesis control.

    Science.gov (United States)

    Merrill, Daniel R; Lockhart, Joseph; Troyk, Phil R; Weir, Richard F; Hankin, David L

    2011-03-01

    Modern hand and wrist prostheses afford a high level of mechanical sophistication, but the ability to control them in an intuitive and repeatable manner lags. Commercially available systems using surface electromyographic (EMG) or myoelectric control can supply at best two degrees of freedom (DOF), most often sequentially controlled. This limitation is partially due to the nature of surface-recorded EMG, for which the signal contains components from multiple muscle sources. We report here on the development of an implantable myoelectric sensor using EMG sensors that can be chronically implanted into an amputee's residual muscles. Because sensing occurs at the source of muscle contraction, a single principal component of EMG is detected by each sensor, corresponding to intent to move a particular effector. This system can potentially provide independent signal sources for control of individual effectors within a limb prosthesis. The use of implanted devices supports inter-day signal repeatability. We report on efforts in preparation for human clinical trials, including animal testing, and a first-in-human proof of principle demonstration where the subject was able to intuitively and simultaneously control two DOF in a hand and wrist prosthesis.

  12. Amputation and prosthesis implantation shape body and peripersonal space representations

    OpenAIRE

    2013-01-01

    Little is known about whether and how multimodal representations of the body (BRs) and of the space around the body (Peripersonal Space, PPS) adapt to amputation and prosthesis implantation. In order to investigate this issue, we tested BR in a group of upper limb amputees by means of a tactile distance perception task and PPS by means of an audio-tactile interaction task. Subjects performed the tasks with stimulation either on the healthy limb or the stump of the amputated limb, while wearin...

  13. Penile prosthesis implant: scientific advances and technological innovations over the last four decades

    Science.gov (United States)

    2017-01-01

    Despite introduction of oral phosphodiesterase type 5 inhibitors and intracavernosal vasoactive agents, penile prosthesis implant remains a relevant and desired option with sales of penile prostheses continue to stay high, as many men became refractory to medical therapy and/or seeking a more effective and permanent therapy. There are two types of penile prosthesis implants: inflatable and non-inflatable types, and the inflatable penile implants can be subdivided into single-, two- and three-piece devices. Non-inflatable penile prosthesis (non-IPP) may be referred to as semi-rigid rod or malleable prosthesis. IPP is considered a superior option to malleable prosthesis as it produces penile rigidity and flaccidity that closely replicates a normal penile erectile function. Since the introduction of IPP by Scott in 1973, surgical landscape for penile prosthesis implantation has changed dramatically. Advances in prosthesis design, device technologies and surgical techniques have made penile prosthesis implant a more natural, durable and reliable device. The following article reviews the scientific advances and technological innovation in modern penile prosthesis implants over the last four decades. PMID:28217449

  14. Regulation of Blood Vessel Sprouting

    Science.gov (United States)

    Chappell, John C; Wiley, David M; Bautch, Victoria L

    2012-01-01

    Blood vessels are essential conduits of nutrients and oxygen throughout the body. The formation of these vessels involves angiogenic sprouting, a complex process entailing highly integrated cell behaviors and signaling pathways. In this review, we discuss how endothelial cells initiate a vessel sprout through interactions with their environment and with one another, particularly through lateral inhibition. We review the composition of the local environment, which contains an initial set of guidance cues to facilitate the proper outward migration of the sprout as it emerges from a parent vessel. The long-range guidance and sprout stability cues provided by soluble molecules, extracellular matrix components, and interactions with other cell types are also discussed. We also examine emerging evidence for mechanisms that govern sprout fusion with its target and lumen formation. PMID:22020130

  15. Tea May Benefit Blood Vessels

    Institute of Scientific and Technical Information of China (English)

    华剑铭

    2000-01-01

    读到有关饮茶有益健康的消息,我总是充满了自豪感:茶的故乡毕竟在中国。饮茶对人的心脏有益,这已经不是新闻,但是到底如何起到此类保健作用,多年来一直是一个谜。本文揭开了此谜底: Drinking a cup of tea makes blood vessels work better within 2 hours, dilating(扩张)the arteries(动脉)and improving blood flow. 文章令我感动之处在于那些科研人员的敬业精神。比如茶中含有caffeine(咖啡因),饮茶对心脏有利,此“利”是否源于caffeine呢?试验人员为了弄清这 一点,便让另一组受试人员服用等量的caffeine,结果证实:Caffeine had no response on the blood vessel function.】

  16. Photoacoustic determination of blood vessel diameter.

    NARCIS (Netherlands)

    Kolkman, R.G.; Klaessens, J.H.G.M.; Hondebrink, E.; Hopman, J.C.W.; Mul, F.F. de; Steenbergen, W.; Thijssen, J.M.; Leeuwen, T.G. van

    2004-01-01

    A double-ring sensor was applied in photoacoustic tomographic imaging of artificial blood vessels as well as blood vessels in a rabbit ear. The peak-to-peak time (tau(pp)) of the laser (1064 nm) induced pressure transient was used to estimate the axial vessel diameter. Comparison with the actual ves

  17. Implantable Prosthesis of Osseous Conduction (BAHA: Case Report

    Directory of Open Access Journals (Sweden)

    Stumpf, Claudia Mittelmann

    2011-04-01

    Full Text Available Introduction: The implantable prosthesis of osseous conduction (BAHA is deemed to be an excellent option in the auditory rehabilitation of patients with conductive and mixed hearing loss, unilaterally or bilaterally, and unilateral sensorineural hearing loss. It has been a good advantage over the conservative bone conduction apparatus and those of individual sound-amplifier apparatus (ISAA, when their usage becomes unfeasible because of chronic otitis externa, which has a hard clinic control. Objective: To introduce the first BAHA case performed in Brazil, as duly authorized by ANVISA (National Agency for Sanitary Surveillance, to rehabilitate the mixed hearing loss with occurrences of chronic otitis externa. Method: 50-year-old female patient with right-ear moderate and left-ear severe hearing loss, bilateral tinnitus derived from otosclerosis, was submitted to 04 surgeries of stapedotomy and unable to use ISAA as a result of otorrhea and bilateral otalgia. The medical and audiological evaluation indicated the benefit of using BAHA. Having surgery been performed and BAHA implemented, the patient showed a significant improvement in audiometric thresholds, speech perception and distinction, as well as she declared to be extremely satisfied with the esthetic factor. Final commentaries: BAHA surgical process is safe, simple and swift, thus providing excellent audiological results and a higher degree of satisfaction to patients.

  18. Design and in-vitro evaluation of a tissue engineered large vessel prosthesis

    Science.gov (United States)

    Mahmood, Ayesha

    Tissue engineering of large diameter blood vessels can offer a promising long-term solution to the large population suffering from congenital vascular defects and other vascular disease. In this report design, assembly, in vitro maturation and evaluation of a large diameter, chitosan-based prosthesis is described. To facilitate cell adhesion and proliferation, collagen was included as a scaffold component to a chitosan scaffold. In vitro studies evaluated the role of collagen content, crosslinker type and crosslinking density on degradation kinetics, mechanical properties and cellular interactions. Finally, the vessel scaffold (ID = 12 mm, OD = 15 mm) was fabricated from a moderately cross-linked, 90%/10% chitosan/collagen material. A tubular scaffold with gradient porosity and interconnected pores was generated by controlled freezing and lyophilization of the polymer. For graft culture laminar and pulsatile flow systems were designed and porous scaffolds were seeded with vascular cells under static conditions. Laminar system grafts were seeded and cultured/analyzed over an 8 week period (15ml/min). For the pulsatile system SMC were seeded and after 2 weeks of pulsatile flow culture (360ml/min, 82 beats/min) microvascular EC were seeded lumenally to initiate a microvascular network followed by aortic EC seeding at 3 weeks. For both systems, cell viability at different culture periods showed the formation of high density of cell within few weeks of graft culture. However, the pulsatile flow system graft showed a significant increase in mechanical properties and ECM protein (collagen and elastin) deposition overtime. This novel chitosan based tissue engineered vascular graft shows promising results for large vessel replacements.

  19. Complete Blood Count and Retinal Vessel Calibers

    OpenAIRE

    Gerald Liew; Jie Jin Wang; Elena Rochtchina; Tien Yin Wong; Paul Mitchell

    2014-01-01

    OBJECTIVE: The influence of hematological indices such as complete blood count on microcirculation is poorly understood. Retinal microvasculature can be directly visualized and vessel calibers are associated with a range of ocular and systemic diseases. We examined the association of complete blood count with retinal vessel calibers. METHODS: Cross-sectional population-based Blue Mountains Eye Study, n = 3009, aged 49+ years. Complete blood count was measured from fasting blood samples taken ...

  20. Tilting of posterior mandibular and maxillary implants for improved prosthesis support.

    Science.gov (United States)

    Krekmanov, L; Kahn, M; Rangert, B; Lindström, H

    2000-01-01

    Rehabilitation of atrophied edentulous arches with endosseous implants in the posterior regions is often associated with anatomic problems such as jaw shape and location of the mental loop, mandibular canal, and maxillary sinuses. The purpose of this investigation was to modify the method for implant placement in the posterior part of the jaws to extend fixed implant-connected prostheses further distally, and to reduce the length of cantilevers in complete-arch prostheses without transpositioning the mandibular nerve or performing bone grafting in the maxilla. Forty-seven consecutive patients were treated with implants (25 patients/36 mandibular implants, 22 patients/30 maxillary implants) placed in tilted positions. They were followed a mean of 40 months (mandibles) and 53 months (maxillae). In the mandible, implants close to the mental foramina were tilted posteriorly approximately 25 to 35 degrees. In the maxilla, the posterior implants were placed close to and parallel with the sinus walls and were titled anteriorly/posteriorly approximately 30 to 35 degrees. Patients gained a mean distance of 6.5 mm of prosthesis support in the mandible and 9.3 mm in the maxilla, as a result of implant tilting. There were no implant failures in mandibles. The cumulative success rates in the maxilla at 5 years were 98% for tilted implants and 93% for non-tilted implants. Paresthesias of the mental nerve were observed on 4 sides during the first 2 to 3 weeks after implant placement. Analysis of the load distribution in one mandibular case showed no significant difference between tilted and the non-tilted implants, and the improved prosthesis support was confirmed. Satisfactory medium-term results concerning osseointegration and significant extension of prosthesis support show that the method can be recommended. This technique may allow for longer implants to be placed with improved bone anchorage.

  1. Implant supported prosthesis in an edentulous boy with Hypohidrotic Ectodermal Dysplasia - "A happy boy"

    DEFF Research Database (Denmark)

    Gjørup, Hans; Nyhuus, Lone; Buhl, Jytte

    2009-01-01

    Implant supported prosthesis in an edentulous boy with Hypohidrotic Ectodermal Dysplasia - "A happy boy". Authors; Gjoerup,H1; Nyhuus,L2; Buhl,J3. 1) Center for Oral Health in Rare Conditions, Aarhus University Hospital 2) Prosthodontic Department, the Dental School, Aarhus University 3) Department...... region. 3. At the age of 10 years a new set of dentures were made. This time the upper denture was made as an overdenture supported and retained by 4 implants and a Dolder bar. The surgical procedure included bone grafting from the anterior ramus mandibulae. The boy's subjective judgement of his oral...... health has been registered. The boy and his family experience great improvement in the functioning as well as the comfort of his prosthesis after insertion of implants. Conclusion The prosthesis for edentulous boys with HED demand several adjustments and revisions, partly due to growth of the jaws...

  2. Implantation of a titanium partial limb prosthesis in a white-naped crane (Grus vipio).

    Science.gov (United States)

    Rush, E Marie; Turner, Thomas M; Montgomery, Ronald; Ogburn, Anna L; Urban, Robert M; Sidebothum, Chris; LaVasser, Andrew

    2012-09-01

    A female white-naped crane (Grus vipio) was presented with an open, oblique fracture of the distal right tarsometatarsus and concomitant vascular and nerve damage. Conventional fracture fixation repairs failed, which led to implantation of a custom titanium limb prosthesis. After subsequent revisions with 2 different prosthetic devices, limb function was ultimately restored but a later yolk embolism caused a circulatory compromise in the opposite leg, which necessitated euthanasia. Histopathologic results revealed limited ingrowth of bone into the porous coated implant, which indicated that a limb prosthesis may provide salvage for long-legged, heavy-bodied birds with fractures of the tarsometatarsus.

  3. Self and partner satisfaction rates after 3 part inflatable penile prosthesis implantation

    Directory of Open Access Journals (Sweden)

    Abdulmuttalip Simsek

    2014-09-01

    Full Text Available Objective: To evaluate and present satisfaction rates of our patients and their partners after 3 part inflatable penile prosthesis implantation. Materials and methods: We searched our hospital electronic data for patients who underwent inflatable penile prosthesis implantation between January 2008 and July 2013. Computer and archived file data were used to get information and reach the patients. We made telephone calls to patients and asked questionnaires about self and partner satisfaction rates. Results: 36 patients underwent prosthesis implantation during the 5 year period. We were able to reach by telephone call 18 of them. The mean age of 18 patients was 55.7 ± 9.4 years and mean body mass index was 24.6 ± 2.1 kg/m2. The etiology was diabetes mellitus on 14 (77.8% and radical pelvic surgery on 4 (22.2% patients. 14 of 18 patients had penile Doppler ultrasound test. Doppler ultrasound demonstrated venous insufficiency in 8 and arterial insufficiency in 6 patients. Mean time from implantation to study was 20.8 ± 13.9 months. Out of 18 patients 2 had prosthesis removal operation because of infection in one patient and perforation in the other. Satisfaction rate was 88.9%, and recommendation rate was 94.4%. Causes of dissatisfaction were pain in one patient and insufficient rigidity plus shortening of the penis in the other one. Partner satisfaction rate was 94.4%. Conclusion: Penile Prosthesis Implantation (PPI is the gold standard treatment of erectile dysfunction (ED irresponsive to medical treatment. Infection and mechanical failure rates are going to be less according to the improvements in synthetic materials and coverings of the prosthesis, so patient and partner satisfaction rates will be higher.

  4. 罂粟碱不同给药途径对肢体损伤血管修复术后皮肤温度的影响%Influence of narceine using pathway on skin temperature after blood vessel prosthesis of limp injury

    Institute of Scientific and Technical Information of China (English)

    王应琼; 韩月明; 谭艳庆; 梁晓青; 陈玉梅; 叶惠萍

    2011-01-01

    Objective : To discuss the impact of difference narceine medication pathway on skin temperature after blood vessel prosthesis of limp injury. Methods:120 patients with limp injury were divided into treatment group A( take oreally narceine ) , treatment group B( intramuscular injection narceine ) , treatment group C( mainline narceine ) and control group( without vasodilator ), 30 patients in each group. To observe the limp temperature after blood vessel prosthesis by infrared skin temperature viewer,to observe the correlation of injury limp survival rate and vascular stria occurate and skin temperature change after different pathway . Results: After used narceine the injury limp skin temperature was improved and difference of skin temperature was reduced( P <0.05 ). The vascular stria occurate of treatment group was lower than that of control group,while the limp survival rate wan higher than that of control group,but there were no statistical sense( all P >0. 05 ). The fastest rise of skin temperature was mainline narceine,the next was intramuscular injection narceine,the last was take oreally narceine , but the continue time was contrary. Conclusion : Narceine with different given pathway could improve skin temperature after blood vessel prosthesis of limp injury , mainline narceine is the best Medication pathway,the next is intramuscular injection.%目的:了解罂粟碱在不同给药途径下对肢体血管修复术后皮肤温度的影响.方法:选择肢体损伤后需行血管修复指(趾)体才能存活和皮瓣移植修复皮缺损的患者120例,随机分为治疗组A(口服罂粟碱)、治疗组B(肌内注射罂粟碱),治疗组C(静脉注射罂粟碱)和对照组(不给予任何血管扩张药)各30例.用红外线皮温观察仪持续观察血管修复术后患者的肢体温度,对比罂粟碱不同给药途径对皮温差的影响、患者血管危象与指(趾)体皮瓣成活率、药物起效时间和持续时间.结果:治疗组应用罂粟

  5. A novel knee prosthesis model of implant-related osteo- myelitis in rats

    DEFF Research Database (Denmark)

    Søe, Niels H.; Jensen, Nina Vendel; Nürnberg, Birgit Meinecke;

    2012-01-01

    There have been numerous reports of animal models of osteomyelitis. Very few of these have been prosthesis models that imitate human conditions. We have developed a new rat model of implant-related osteomyelitis that mimics human osteomyelitis, to investigate the pathology of infection after...

  6. Effects of vestibular prosthesis electrode implantation and stimulation on hearing in rhesus monkeys.

    Science.gov (United States)

    Dai, Chenkai; Fridman, Gene Y; Della Santina, Charles C

    2011-07-01

    To investigate the effects of vestibular prosthesis electrode implantation and activation on hearing in rhesus monkeys, we measured auditory brainstem responses (ABR) and distortion product otoacoustic emissions (DPOAE) in four rhesus monkeys before and after unilateral implantation of vestibular prosthesis electrodes in each of 3 left semicircular canals (SCC). Each of the 3 left SCCs were implanted with electrodes via a transmastoid approach. Right ears, which served as controls, were not surgically manipulated. Hearing tests were conducted before implantation (BI) and then 4 weeks post-implantation both without electrical stimulation (NS) and with electrical stimulation (S). During the latter condition, prosthetic electrical stimuli encoding 3 dimensions of head angular velocity were delivered to the 3 ampullary branches of the left vestibular nerve via each of 3 electrode pairs of a multichannel vestibular prosthesis. Electrical stimuli comprised charge-balanced biphasic pulses at a baseline rate of 94 pulses/s, with pulse frequency modulated from 48 to 222 pulses/s by head angular velocity. ABR hearing thresholds to clicks and tone pips at 1, 2, and 4 kHz increased by 5-10 dB from BI to NS and increased another ∼5 dB from NS to S in implanted ears. No significant change was seen in right ears. DPOAE amplitudes decreased by 2-14 dB from BI to NS in implanted ears. There was a slight but insignificant decrease of DPOAE amplitude and a corresponding increase of DPOAE/Noise floor ratio between NS and S in implanted ears. Vestibular prosthesis electrode implantation and activation have small but measurable effects on hearing in rhesus monkeys. Coupled with the clinical observation that patients with cochlear implants only rarely exhibit signs of vestibular injury or spurious vestibular nerve stimulation, these results suggest that although implantation and activation of multichannel vestibular prosthesis electrodes in human will carry a risk of hearing loss

  7. Penile prosthesis implant for erectile dysfunction: A new minimally invasive infrapubic surgical technique

    Directory of Open Access Journals (Sweden)

    Gabriele Antonini

    2016-01-01

    Full Text Available Erectile dysfunction, the most common male sexual disorder after premature ejaculation, with its important impact on man and partner’s sexuality and quality of life is a persistent inability to obtain and maintain an erection sufficient to permit satisfactory sexual performance. Non-surgical treatments with controversial results are usually applyed before surgical treatment that has reached high levels of satisfaction. We describe a new surgical technique to implant three-pieces penile prosthesis in patients suffering from erectile dysfunction (ED not responding to conventional medical therapy or reporting side effects with such a therapy. Implantation of an inflatable prosthesis, for treatment of ED, is a safe and efficacious approach with high satisfaction reported by patients and partners. Surgical technique should be minimally invasive and latest technology equipment should be implanted in order to decrease common complications and to obtain a better aesthetic result.

  8. Corporoplasty using bovine pericardium grafts in complex penile prosthesis implantation surgery

    Directory of Open Access Journals (Sweden)

    Eduardo J. A. Lopes

    2009-02-01

    Full Text Available Purpose: This paper is the first, to our knowledge, to propose the use of a bovine pericardium graft in corporoplasty for penile prosthesis implantation. The advantages of bovine pericardium graft have been demonstrated by its use in cardiac surgery, including low cost, biocompatibility, impermeability, resistance to dilatation, flexibility, low likelihood of retraction, absence of antigenic reaction and natural absorption of the tissue. In this paper, we propose the use of this heterologous material graft in corporoplasty for penile prosthesis implantation. Materials and Methods: Five patients with a history of erosion, infection and fibrosis, mean time of follow-up 32 months (range 9-48 months. Bovine pericardium was used to cover large areas of implanted penile prostheses when use of the tunica albuginea was unfeasible. Results: The surgical procedure resulted in no complications in all patients. Conclusions: Bovine pericardium may substitute synthetic and autologous material with the additional advantages of lower cost and greater availability.

  9. Three-year outcomes after transcatheter aortic valve implantation with the CoreValve prosthesis.

    Science.gov (United States)

    Gotzmann, Michael; Czauderna, Anna; Hehnen, Tobias; Aweimer, Assem; Lind, Alexander; Kloppe, Axel; Bösche, Leif; Mügge, Andreas; Ewers, Aydan

    2014-08-15

    There is little known about the long-term results of the CoreValve prosthesis. The aim of this study was to assess the 3-year clinical and hemodynamic outcomes of the CoreValve prosthesis. One hundred fifty consecutive patients with severe aortic stenosis successfully underwent transcatheter aortic valve implantation (TAVI) with the CoreValve prosthesis. The primary study end point was death from any cause after TAVI. The secondary end points were defined as (1) cardiovascular death and (2) prosthesis-related mortality and morbidity. At 1 to 3 years, all-cause mortality rates were 25%, 32%, and 41%, respectively, and cardiovascular mortality rates were 14%, 21%, and 27%, respectively. Before TAVI, 95% of patients were in New York Heart Association class III or IV. Of the surviving patients, rates of New York Heart Association class III or IV at 1 to 3 years were 33%, 39%, and 38%, respectively. There was an annual decrease of the valve area of approximately 0.1 cm². Aortic restenosis occurred in 2 patients. Moderate or severe aortic regurgitation (AR) occurred in 15% of patients immediately after TAVI. Twenty patients (13%) had a slight worsening of AR within 3 years. New severe AR did not occur. The incidence of prosthesis-related endocarditis was 0.66% per year. Overall, 7 patients (incidence of 1.5% per year) had a clinically relevant problem of the prosthesis. In conclusion, TAVI with the CoreValve prosthesis had favorable effects on symptoms and outcomes even after 3 years. These results are clouded by side effects, such as AR and prosthesis-related mortality and morbidity.

  10. Implantation of the Argus II Retinal Prosthesis in an Eye With Short Axial Length.

    Science.gov (United States)

    Montezuma, Sandra R; Tang, Peter H; van Kuijk, Frederik J G M; Drayna, Paul; Koozekanani, Dara D

    2016-04-01

    The authors describe the implantation of the Argus II Retinal Prosthesis System (Argus II) (Second Sight Medical Products, Sylmar, CA) into a short axial length (AL) eye. The authors' main modification is the use of endocyclophotocoagulation (endo-CPC) to the ciliary processes in the area that the cable enters through the sclerotomy. This case describes the surgical technique necessary for successful implantation of the Argus II into a short AL eye. The use of endo-PC prevents chafing to the ciliary processes, does not affect postoperative intraocular pressure, and facilitates direct visualization of the structures during the surgery, preventing damage during implantation.

  11. Trends in Tissue Engineering for Blood Vessels

    Directory of Open Access Journals (Sweden)

    Judee Grace Nemeno-Guanzon

    2012-01-01

    Full Text Available Over the years, cardiovascular diseases continue to increase and affect not only human health but also the economic stability worldwide. The advancement in tissue engineering is contributing a lot in dealing with this immediate need of alleviating human health. Blood vessel diseases are considered as major cardiovascular health problems. Although blood vessel transplantation is the most convenient treatment, it has been delimited due to scarcity of donors and the patient’s conditions. However, tissue-engineered blood vessels are promising alternatives as mode of treatment for blood vessel defects. The purpose of this paper is to show the importance of the advancement on biofabrication technology for treatment of soft tissue defects particularly for vascular tissues. This will also provide an overview and update on the current status of tissue reconstruction especially from autologous stem cells, scaffolds, and scaffold-free cellular transplantable constructs. The discussion of this paper will be focused on the historical view of cardiovascular tissue engineering and stem cell biology. The representative studies featured in this paper are limited within the last decade in order to trace the trend and evolution of techniques for blood vessel tissue engineering.

  12. OBSERVATIONS ON VASCULAR PATTERN OF CHORIONIC BLOOD VESSELS OF PLACENTA

    Directory of Open Access Journals (Sweden)

    Yousuf Sarwar

    2013-10-01

    Full Text Available ABSTRACT: BACKGROUND: Placenta is a choriodecidual structure develops during pregnancy implanted on the uterine wall and car ries vital functions. It is connected to the foetus through umbilical cord. The branches of umbilical vessels that traverse along foetal surface of placenta are referred as chorionic vessels. There are two different patterns of chorionic vessels – Dispersa l and Magistral. In the dispersal type, the umbilical vessels undergo successive divisions with gradually diminishing caliber towards periphery while in magistral pattern the vessels traverse to the edge of placenta without appreciable decrease in diameter of vessels. The present study has been done for visualization of the pattern of chorionic vessels in placenta obtained from labour room of a tertiary care hospital in eastern Bihar, India. MATERIALS AND METHODS: A total of one hundred and fifty (150 fres h and intact placenta of full term pregnancies collected from Obstetrics & Gynaecology department were included in the study. After washing with distilled water, removal of blood clots were done with slight digital pressure applied over arteries and vein a nd later on by irrigation with saline. The cut end of the umbilical cord was carefully visualized to identify the umbilical arteries and vein. Dye was injected into umbilical vessels under normal physiological pressure and diameter of chorionic blood vesse ls were taken at the center and periphery. Ultimately each vessel was followed and examined to observe the dispersal and magistral pattern of chorionic blood vessels of placenta. RESULTS AND CONCLUSION: Out of the total of one hundred and fifty (150 full term placenta obtained and examined in the Anatomy department during the study period, 64% Dispersal type & 36 % of Magistral type of arterial pattern of branching of chorionic vessels were observed. Vein and its tributaries presented Dispersal pattern in 60% and Magistral pattern in 40%. There is a significant

  13. Effect of veneering material on the deformation suffered by implant-supported fixed prosthesis framework

    Directory of Open Access Journals (Sweden)

    Antônio Francisco GRANDO

    2014-06-01

    Full Text Available Knowing how stresses are dissipated on the fixed implant-supported complex allows adequate treatment planning and better choice of the materials used for prosthesis fabrication. Objectives: The aim of this study was to evaluate the deformation suffered by cantilevered implant-supported fixed prostheses frameworks cast in silver-palladium alloy and coated with two occlusal veneering materials: acrylic resin or porcelain. Material and Methods: Two strain gauges were bonded to the inferior surface of the silver-palladium framework and two other were bonded to the occlusal surface of the prosthesis framework covered with ceramic and acrylic resin on each of its two halves. The framework was fixed to a metallic master model and a 35.2 N compression force was applied to the cantilever at 10, 15 and 20 mm from the most distal implant. The measurements of deformation by compression and tension were obtained. The statistical 2-way ANOVA test was used for individual analysis of the experiment variables and the Tukey test was used for the interrelation between all the variables (material and distance of force application. Results: The results showed that both variables had influence on the studied factors (deformation by compression and tension. Conclusion: The ceramic coating provided greater rigidity to the assembly and therefore less distortion compared with the uncoated framework and with the resin-coated framework. The cantilever arm length also influenced the prosthesis rigidity, causing higher deformation the farther the load was applied from the last implant.

  14. Fabricating a Soft Liner-Retained Implant-Supported Palatal Lift Prosthesis for an Edentulous Patient: A Case Report

    Directory of Open Access Journals (Sweden)

    Omid Savabi

    2012-01-01

    Full Text Available This case report describes fabrication of a palatal lift prosthesis for a quadriplegic edentulous 30-year-old male with past head traumatic injury. We constructed an implant supported bar and used a soft-lining material for the maxillary palatal lift prosthesis to minimize the possibility of implant overloading and also provide a less complex and less expensive procedure for this patient.

  15. Penile prosthesis implantation in Chinese patients with severe erectile dysfunction: 10-year experience.

    Science.gov (United States)

    Song, Wei-Dong; Yuan, Yi-Ming; Cui, Wan-Shou; Wu, Alex K; Zhu, Yi-Chen; Liu, Jing; Wang, Lin; Bai, Guang-Yi; Peng, Jing; Zhang, Zhi-Chao; Gao, Bing; Guo, Ying-Lu; Lue, Tom F; Xin, Zhong-Cheng

    2013-09-01

    We retrospectively evaluated the clinical outcome of penile prosthesis implantation (PPI) in Chinese patients with severe erectile dysfunction (SED). From July 2000 to December 2011, 224 patients (mean age: 35.9±11.8 years, range: 20-75 years) with SED underwent PPI by experienced surgeon according to standard PPI procedure at our centre. A malleable prosthesis (AMS 650) was implanted in 45 cases (20.1%), and a three-piece inflatable prosthesis (AMS 700 CXM or AMS 700 CXR) was implanted in 179 cases (79.9%). Surgical outcomes, including postoperative complications, clinical efficacy and couple satisfaction, were evaluated over than 6 months postoperatively using medical record abstraction, IIEF-5, quality of life (QoL) scores, and the patient/partner sexual satisfaction score proposed by Bhojwani et al. Of the 224 patients eligible for the study, 201 subjects (89.7%) completed follow-up. All of patients could perform sexual intercourse post PPI with the mean postoperative IIEF-5 and QoL scores were 20.02±2.32 and 5.28±0.76, respectively, which were significantly improved compared with the preoperative scores (6.29±1.5 and 2.13±0.84, PPatient satisfaction in the three-piece inflatable prosthesis group was higher than in the malleable prosthesis group (Ppatients with SED and experienced surgeon perform PPI according to standard PPI procedure could reduce the postoperative complications of PPI and could improve patient satisfaction ratio and QoL.

  16. Prosthesis auricular with osseointegrated implants and quality of life.

    Science.gov (United States)

    dos Santos, Daniela Micheline; Goiato, Marcelo Coelho; Pesqueira, Aldiéres Alves; Bannwart, Lisiane Cristina; Rezende, Maria Cristina Rosifini Alves; Magro-Filho, Osvaldo; Moreno, Amália

    2010-01-01

    Implants in craniofacial reconstructions improve prostheses retention and stability, comfort, and safety for the patient. According to biomechanical principles, the treatment success regarding osseointegration maintenance depends on an adequate surgery technique associated to a retention system that provides favorable tension distribution to implants. Implants in the mastoid area are a very important aid for retention of auricular prostheses. Color stability of resin and silicone is an important factor for longevity of auricular prostheses, and the high degree of satisfaction of patients with head and neck defects receiving epithesial reconstruction in the maxillofacial region is demonstrated.

  17. Impression technique for a complete-arch prosthesis with multiple implants using additive manufacturing technologies.

    Science.gov (United States)

    Revilla-León, Marta; Sánchez-Rubio, José Luis; Oteo-Calatayud, Jesús; Özcan, Mutlu

    2016-11-23

    This article describes an impression technique for a complete-arch prosthesis supported by multiple implants where additive manufacturing technologies were used to fabricate a splinting framework and a custom tray. The technique presented uses a shim method to control the homogenous splinting acrylic resin and impression material during the procedure, thereby reducing laboratory and chairside time and the number of impression copings and laboratory analogs needed.

  18. Acquisition of myoelectric signals to control a hand prosthesis with implantable epimysial electrodes.

    Science.gov (United States)

    Ruff, Roman; Poppendieck, Wigand; Gail, Alexander; Westendorff, Stephanie; Russold, Michael; Lewis, Soren; Meiners, Thomas; Hoffmann, Klaus-Peter

    2010-01-01

    The acquisition of myoelectric signals from the Musculus deltoideus of a rhesus monkey is described. Such signals are aimed to be used as control signal for an active myoelectric hand prosthesis. For recording, implantable flexible, polyimide-based multi-site microelectrodes were placed epimysially on the muscle. EMG signals were recorded during voluntary goal-directed movements of the arm, and analyzed with respect to signal amplitude and frequency.

  19. The periodontal prosthesis mode of transition to an implant-supported dentition.

    Science.gov (United States)

    Hunt, Peter; Norkin, Frederic; Serrano, Julian

    2006-01-01

    In recent years, implant-supported reconstructions have become a welcome alternative to dentures for those who have lost their natural dentition. While the benefits of the final implant-supported reconstruction may be obvious, the planning and execution of therapy to achieve this result may be bewildering to many dentists. Four main modes of transfer have evolved: an uncontrolled or "haphazard" transition; the traditional "dentures first" mode, an immediate transition, and a staged transition. This article proposes an additional mode of transition called periodontal prosthesis, which has the potential to make the transition process smoother and more predictable while providing optimal retention of alveolar supporting structures and generating optimal esthetics.

  20. Retrieval technique for full-arch implant-supported fixed prosthesis: a clinical report.

    Science.gov (United States)

    Simamoto-Júnior, Paulo César; Fernandes-Neto, Alfredo Júlio; Neves, Flávio Domingues; Dantas, Talita Souza; Naves, Lucas Zago

    2015-02-01

    In the event of the loss of an implant and to take advantage of the preexisting structures, a rescue procedure that allows continuous use of the original fixed restoration during the restoration of the tripod support at the implant level can be used. When nonphysiological occlusion forces are avoided, the success rate of this rescue procedure is very similar to any other rehabilitation made following a conventional protocol. Furthermore, the fact that the patient has already adapted to the prosthesis position and its vertical dimension results in easier functional adaptation in the postoperative period and, consequently, greater comfort.

  1. Pseudo-capsule “coffin effect”: How to prevent penile retraction after implant of three-piece inflatable prosthesis

    Directory of Open Access Journals (Sweden)

    Enrico Caraceni

    2014-06-01

    Full Text Available Objective: Following three-component implantation of a penile prosthesis, some patients are dissatisfied with their penile length. This may be due to the procedure by itself or pre-existing risk factors or psychological reasons. We supposed that formation of a restricted pseudo-capsule due to a late prosthesis activation can inhibit later system expansion. We aimed to identify the presence or absence of penile retraction after implant and to prevent it by immediate prosthesis activation after implantation. Material and methods. Forty-six patients operated with three-piece inflatable penile prosthesis (AMS 700 CX o LGX were enrolled. In 27 patients prosthesis was first activated four weeks after surgery (NEA group and in 19 patients prosthesis was activated immediately after surgery (DEA group. Length and girth of the penis was evaluated before (in DEA group and after the surgical procedure. Results. The average post implant dorsal length of the erect penis in group NEA was found 3.28 cm shorter than in group with early activation (DEA. In DEA group there was no lenght difference between pre-operative stretching (14.57 cm and post operative erection (14.98 cm. When early activation was not performed, the clinical result was a smaller penis in erect phase. Conclusion. Reduced lenght of the penis after implantation can be caused by the presence of a pseudo-capsule that limits the elongation of the prosthesis and of the penis (“coffin effect”. Timing of first activation seems to be the key in order to prevent the risk of penile retraction after implantation. Early activation is identified as the best measure to maintain the length of the pre implant erect penis after the prosthetic hydraulic implant.

  2. Free Gingival Graft to Increase Keratinized Mucosa after Placing of Mandibular Fixed Implant-Supported Prosthesis

    Science.gov (United States)

    Marcantonio, Elcio

    2017-01-01

    Insufficiently keratinized tissue can be increased surgically by free gingival grafting. The presence or reconstruction of keratinized mucosa around the implant can facilitate restorative procedure and allow the maintenance of an oral hygiene routine without irritation or discomfort to the patient. The aim of this clinical case report is to describe an oral rehabilitation procedure of an edentulous patient with absence of keratinized mucosa in the interforaminal area, using a free gingival graft associated with a mandibular fixed implant-supported prosthesis. The treatment included the manufacturing of a maxillary complete denture and a mandibular fixed implant-supported prosthesis followed by a free gingival graft to increase the width of the mandibular keratinized mucosa. Free gingival graft was obtained from the palate and grafted on the buccal side of interforaminal area. The follow-up of 02 and 12 months after mucogingival surgery showed that the free gingival graft promoted peri-implant health, hygiene, and patient comfort. Clinical Significance. The free gingival graft is an effective treatment in increasing the width of mandibular keratinized mucosa on the buccal side of the interforaminal area and provided an improvement in maintaining the health of peri-implant tissues which allows for better oral hygiene. PMID:28293441

  3. Treatment of a maxillary dento-alveolar defect using an immediately loaded definitive zygoma implant-retained prosthesis with 11-month follow-up: a clinical report.

    Science.gov (United States)

    Baig, Mirza Rustum; Rajan, Gunaseelan

    2010-01-01

    This article describes the dental implant-based rehabilitation of a partially edentulous patient with a unilateral maxillary dento-alveolar defect. A screw-retained prosthesis with a modified design was fabricated on zygomatic and regular dental implants. One section of the implant prosthesis has cemented crowns and the other section is conventional screw-retained. The design of the prosthesis overcame the hard and soft tissue deficit and provided the desired esthetics.

  4. Immersive volume rendering of blood vessels

    Science.gov (United States)

    Long, Gregory; Kim, Han Suk; Marsden, Alison; Bazilevs, Yuri; Schulze, Jürgen P.

    2012-03-01

    In this paper, we present a novel method of visualizing flow in blood vessels. Our approach reads unstructured tetrahedral data, resamples it, and uses slice based 3D texture volume rendering. Due to the sparse structure of blood vessels, we utilize an octree to efficiently store the resampled data by discarding empty regions of the volume. We use animation to convey time series data, wireframe surface to give structure, and utilize the StarCAVE, a 3D virtual reality environment, to add a fully immersive element to the visualization. Our tool has great value in interdisciplinary work, helping scientists collaborate with clinicians, by improving the understanding of blood flow simulations. Full immersion in the flow field allows for a more intuitive understanding of the flow phenomena, and can be a great help to medical experts for treatment planning.

  5. Maintenance of bone mineral density after implantation of a femoral neck hip prosthesis

    Directory of Open Access Journals (Sweden)

    Zurstegge Matthias

    2008-01-01

    Full Text Available Abstract Background Stress shielding of the proximal femur has been observed in a number of conventional cementless implants used in total hip arthroplasty. Short femoral-neck implants are claiming less interference with the biomechanics of the proximal femur. The goal of this study was to investigate the changes of bone-mineral density in the proximal femur and the clinical outcome after implantation of a short femoral-neck prosthesis. Methods We prospectively assessed the clinical outcome and the changes of bone mineral density of the proximal femur up to one year after implantation of a short femoral neck prosthesis in 20 patients with a mean age of 47 years (range 17 to 65. Clinical outcome was assessed using the Harris Hip Score. The WOMAC was used as a patient-relevant outcome-measure. The bone mineral density was determined using dual energy x-ray absorptiometry, performed 10 days, three months and 12 months after surgery. Results The Harris Hip Score improved from an average preoperative score of 46 to a postoperative score at 12 months of 89 points, the global WOMAC index from 5,3 preoperatively to 0,8 at 12 months postoperatively. In contrast to conventional implants, the DEXA-scans overall revealed a slight increase of bone mineral density in the proximal femur in the 12 months following the implantation. Conclusion The short femoral neck stem lead to a distinct bone reaction. This was significantly different when compared to the changes in bone mineral density reported after implantation of conventional implants.

  6. Zinc oxide nanoflowers make new blood vessels

    Science.gov (United States)

    Barui, Ayan Kumar; Veeriah, Vimal; Mukherjee, Sudip; Manna, Joydeb; Patel, Ajay Kumar; Patra, Sujata; Pal, Krishnendu; Murali, Shruthi; Rana, Rohit K.; Chatterjee, Suvro; Patra, Chitta Ranjan

    2012-11-01

    It is well established that angiogenesis is the process of formation of new capillaries from pre-existing blood vessels. It is a complex process, involving both pro- and anti-angiogenic factors, and plays a significant role in physiological and pathophysiological processes such as embryonic development, atherosclerosis, post-ischemic vascularization of the myocardium, tumor growth and metastasis, rheumatoid arthritis etc. This is the first report of zinc oxide (ZnO) nanoflowers that show significant pro-angiogenic properties (formation of new capillaries from pre-existing blood vessels), observed by in vitro and in vivo angiogenesis assays. The egg yolk angiogenesis assay using ZnO nanoflowers indicates the presence of matured blood vessels formation. Additionally, it helps to promote endothelial cell (EA.hy926 cells) migration in wound healing assays. Formation of reactive oxygen species (ROS), especially hydrogen peroxide (H2O2)--a redox signaling molecule, might be the plausible mechanism for nanoflower-based angiogenesis. Angiogenesis by nanoflowers may provide the basis for the future development of new alternative therapeutic treatment strategies for cardiovascular and ischemic diseases, where angiogenesis plays a significant role.It is well established that angiogenesis is the process of formation of new capillaries from pre-existing blood vessels. It is a complex process, involving both pro- and anti-angiogenic factors, and plays a significant role in physiological and pathophysiological processes such as embryonic development, atherosclerosis, post-ischemic vascularization of the myocardium, tumor growth and metastasis, rheumatoid arthritis etc. This is the first report of zinc oxide (ZnO) nanoflowers that show significant pro-angiogenic properties (formation of new capillaries from pre-existing blood vessels), observed by in vitro and in vivo angiogenesis assays. The egg yolk angiogenesis assay using ZnO nanoflowers indicates the presence of matured blood

  7. Comparison of Maxillary Implant-Supported Prosthesis in Irradiated and Non-Irradiated Patients

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Summary: In order to investigate the influence of radiation therapy after the treatment of maxillaryimplant-supported prostheses, 27 patients received a total of 131 implants in maxilla after oral cancertreatment and/or reconstructive surgery. Among them, 25 received maxillary implant-supportedprostheses. The cumulative survival rates of implants and prostheses were evaluated by the product-limit-estimates method according to Kaplan-Meier. The cumulative survival rate of implants andprostheses in irradiated patients was compared with that in non-irradiated patients by statistical Log-rank test. The results showed that 112 implants were observed after implant loading. The implantscumulative survival rate was approximately 65 % for overall patients. The cumulative prosthesis suc-cessful rate was approximately 88 % for all 25 patients. Log-rank test analysis revealed that therewas a significant difference in cumulative implants survival rates between non-irradiated and irradiat-ed maxillary bone (P<0. 01). It was concluded that the implants and prostheses in irradiated pa-tients have significantly lower survival rates than in non-irradiated patients.

  8. In vivo performance of the polyesterurethane Vascugraft prosthesis implanted as a thoraco-abdominal bypass in dogs: an exploratory study.

    Science.gov (United States)

    Zhang, Z; King, M W; Marois, Y; Marois, M; Guidoin, R

    1994-10-01

    Among the various prototype vascular prostheses that have been developed over recent years as small vessel substitutes, the Vascugraft polyurethane device produced by Braun-Melsungen AG has a number of attractive features. As well as having high mechanical compliance similar to that of the arterial tree, it has been manufactured from a specially synthesized poly(ester urethane) with improved biostability and its microfibrous structure provides a highly porous wall with open communicating pores. With a view to evaluating the in vivo biofunctionality and biostability of this prosthesis in the dog, 10 mm diameter grafts were implanted as thoraco-abdominal bypasses for prescheduled periods of 1 months and 12 months, and their performance monitored in terms of gross morphology, histology and the measurement of the chemical and physical properties of the explanted and cleaned specimens. Both grafts were patent at retrieval. Each had a smooth and glistening flow surface without organized mural thrombi and showed the development of a thin collagenous internal capsule with the presence of endothelial-like cells. Both grafts were well encapsulated externally and revealed a small distal bend or kink which is frequently observed by any thoraco-abdominal bypass in dogs. The fresh explanted prostheses were cleaned by a new enzyme treatment which provided specimens for microscopic, mechanical and thermal analyses, as well as studies of the surface and bulk chemistry. By comparing the results from the explanted and cleaned material with those of the virgin prosthesis, we have observed some deterioration in the integrity of the microfibrous structure, some loss in mechanical performance, marginal changes in molecular weight, and an apparent microphase separation of the hard and soft segment domains at a depth of a few microns. While the biofunctionality of a 10 mm calibre device has been demonstrated, additional in vivo studies are recommended to assess the biofunctionality at

  9. Multidisciplinary approach of ectodermal dysplasia with implant retained fixed prosthesis

    Directory of Open Access Journals (Sweden)

    Vishnu Priya

    2013-01-01

    Full Text Available Ectodermal dysplasia represents a group of rare inherited conditions in which two or more ectodermally derived anatomical structures fail to develop. Early dental intervention can improve patient′s appearance, thereby minimizing associated emotional and psychological problems in these patients. Treatment requires a teamwork by medical personnel along with dental professionals of various specialties. Here, a rare case of a young female patient is presented with prosthetic management with implant supported fixed partial denture.

  10. Using the "final-on-four" concept to deliver an immediate metal-resin implant-fixed complete dental prosthesis.

    Science.gov (United States)

    Yilmaz, Burak; Ozcelik, Tuncer Burak; McGlumphy, Edwin

    2015-08-01

    In traditional dental implant therapy, the time between implant placement and delivery of the definitive prosthesis can be long and uncomfortable for a patient wearing a conventional removable denture on an atrophied ridge. New clinical protocols, often with tilted implants, are being used to immediately restore mandibular implants with interim restorations, thus shortening the patient's return to function. However, these conversion type interim restorations do not decrease the time to definitive prosthetic rehabilitation. The Ohio State University (OSU) developed an immediate load surgical and prosthetic protocol to compensate for the disadvantages of previous techniques. With this protocol, a custom, definitive, screw-retained metal-resin fixed prosthesis can be delivered 2 to 4 days postoperatively and has been described using 5 implants. This clinical report presents the OSU immediate loading protocol, combined with a tilted implant technique, for the fabrication of a mandibular metal-resin implant fixed complete dental prosthesis (MRIFCDP) in 3 days postoperatively and with only 4 implants. Replacing the mandibular dentition with an immediate load-fixed metal-resin prosthesis by means of the "final-on-four" technique resulted in a custom, definitive, and functional restorative solution immediately after surgery.

  11. Impact of patient-prosthesis mismatch after transcatheter aortic valve-in-valve implantation in degenerated bioprostheses

    DEFF Research Database (Denmark)

    Seiffert, Moritz; Conradi, Lenard; Baldus, Stephan

    2012-01-01

    Transcatheter valve-in-valve implantation is evolving as an alternative to reoperative valve replacement in high-risk patients with degenerated bioprostheses. Nevertheless, hemodynamic performance is limited by the previously implanted xenograft. We report our experience with patient-prosthesis...

  12. Eye movements as a marker for visual prosthesis spatial mapping - A feasibility study using a blind patient implanted with the Argus II retinal prosthesis.

    Science.gov (United States)

    Caspi, Avi; Dorn, Jessy; Helder, John B; Katyal, Kapil D; Roy, Arup; Caspi, Avi; Dorn, Jessy; Helder, John B; Katyal, Kapil D; Roy, Arup; Helder, John B; Katyal, Kapil D; Dorn, Jessy; Roy, Arup; Caspi, Avi

    2016-08-01

    Spatial mapping, the location in space of a perceived location due to an implanted electrode's electrical stimulation is important in the design of visual prostheses. Generally, a visual prosthesis system consists of an implanted electrode array, an external camera that acquires the image, and a transmitter that sends the information to the implanted electrodes. In cortical visual implant, the layout of the implanted array in most cases does not match the retinotopic map and it is necessary to find the location of the percept of each electrode in world coordinates. Herein, we show the feasibility of using eye movements as markers to construct the spatial map of the implanted electrodes. A blind patient implanted with the Argus II retinal prosthesis was instructed to conduct an eye movement to the location of a percept generated by an electrical stimulation at different retinal locations. By analyzing the eye movements triggered by the electrical stimulation, we were able to reconstruct the spatial map of the electrodes. Our experiment demonstrates that a blind person still maintains control of eye movements that can be used to map the percept location of the implanted electrodes.

  13. The KineSpring® Knee Implant System: an implantable joint-unloading prosthesis for treatment of medial knee osteoarthritis

    Directory of Open Access Journals (Sweden)

    Clifford AG

    2013-05-01

    Full Text Available Anton G Clifford,1 Stefan M Gabriel,1 Mary O’Connell,1 David Lowe,1 Larry E Miller,2,3 Jon E Block31Moximed, Inc, Hayward, CA, USA; 2Miller Scientific Consulting, Inc, Arden, NC, USA; 3The Jon Block Group, San Francisco, CA, USAAbstract: Symptomatic medial compartment knee osteoarthritis (OA is the leading cause of musculoskeletal pain and disability in adults. Therapies intended to unload the medial knee compartment have yielded unsatisfactory results due to low patient compliance with conservative treatments and high complication rates with surgical options. There is no widely available joint-unloading treatment for medial knee OA that offers clinically important symptom alleviation, low complication risk, and high patient acceptance. The KineSpring® Knee Implant System (Moximed, Inc, Hayward, CA, USA is a first-of-its-kind, implantable, extra-articular, extra-capsular prosthesis intended to alleviate knee OA-related symptoms by reducing medial knee compartment loading while overcoming the limitations of traditional joint-unloading therapies. Preclinical and clinical studies have demonstrated excellent prosthesis durability, substantial reductions in medial compartment and total joint loads, and clinically important improvements in OA-related pain and function. The purpose of this report is to describe the KineSpring System, including implant characteristics, principles of operation, indications for use, patient selection criteria, surgical technique, postoperative care, preclinical testing, and clinical experience. The KineSpring System has potential to bridge the gap between ineffective conservative treatments and irreversible surgical interventions for medial compartment knee OA.Keywords: KineSpring, knee, medial, osteoarthritis, prosthesis

  14. [Urethral injuries secondary to implantation of penile prosthesis. Analysis of the causes, prevention and treatment].

    Science.gov (United States)

    Vitarelli, Antonio; Divenuto, Lucia; Palminteri, Enzo; Lorusso, Giovanni; Pagliarulo, Arcangelo

    2014-01-01

    Urethral injuries due to penile prosthesis implant represent a rare complication of the intervention to position penile prosthesis, but unfortunately scientific literature about this is poor. This rare complication may occur during surgery and in the postoperative period, both early and late. It recognizes a variety of causes that may include anatomical or functional conditions, for example cavernosal fibrosis or outcomes of inflammations or previous urethral lesions and pathological sensibility due to diabetic neuropathy or other forms of neuropathy including those from spinal cord injury or myelopathy. This review evaluates the possible predisposing conditions, the clinical presentations, and the devices in the surgical procedures to use to minimize the risk of onset of this lesions and the measures to take if they occur.

  15. 7-Be Implantation in Plastics for Prosthesis Wear Studies

    Science.gov (United States)

    Greife, Uwe; Erikson, L.; Patel, N.; Wimmer, M.; Dwiwedi, Y.; Laurent, M.; Chipps, K.; Blackmon, J.; Kozub, R.; Bardayan, D.; Gross, C.; Stracener, D.; Smith, M.; Nesaraya, C.; Rehm, E.; Ahmed, I.; Greene, J.

    2010-11-01

    The current generation of highly cross linked ultrahigh molecular weight polyethylenes (PE) for hip and knee joint replacement have achieved such low in vitro wear rates that efforts have been underway to develop more sensitive methods to measure polyethylene wear. The most widely used technique, the gravimetric method, suffers from the notable disadvantage that mass gain by fluid absorption can considerably exceed mass loss by wear, making the wear measurement inaccurate, sometimes even leading to negative ``wear'' values. The purpose of this experiment was to investigate the use of a radioactive tracer, beryllium-7 (7-Be), to circumvent the problem of fluid absorption and thereby achieve a much more sensitive and accurate wear measurement. This proof of principle study demonstrated the general feasibility of 7-Be implantation (performed at the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory) for PE wear analysis.

  16. Patients' Expectation Before and Satisfaction After Full-Arch Fixed Implant-Prosthesis Rehabilitation.

    Science.gov (United States)

    da Cunha, Miriã Corália; Santos, Jarbas Francisco Fernandes Dos; Santos, Mateus Bertolini Fernandes Dos; Marchini, Leonardo

    2015-06-01

    This study evaluated patients' expectation before and satisfaction after full-arch fixed implant-prosthesis rehabilitation. Other variables that could influence patient satisfaction with this therapy were also evaluated. Using a visual analog scale (VAS), a sample of 28 patients assigned scores for their expectation before and satisfaction after therapy regarding chewing, esthetics, comfort, and phonetics. They also completed a questionnaire concerning their evaluation of the dentists' conduct. The average VAS scores were high for both expectation prior to treatment and satisfaction after treatment, and there was no statistical difference between them. Women presented higher expectations than men regarding esthetics (P = 0.040), phonetics (P = 0.043) and comfort (P = 0.013). Significant differences were not found between VAS scores with clinical variables (arch, radiographic bone quality, surgical bone quality, and implant inclination), educational level, and patients' evaluation of the dentists' conduct. Considering the results obtained in this study, expectation before implant-supported, full-arch fixed prosthesis therapy were met following treatment, with women having higher expectations than men.

  17. Photoacoustic removal of occlusions from blood vessels

    Science.gov (United States)

    Visuri, Steven R.; Da Silva, Luiz B.; Celliers, Peter M.; London, Richard A.; Maitland, IV, Duncan J.; Esch, Victor C.

    2002-01-01

    Partial or total occlusions of fluid passages within the human body are removed by positioning an array of optical fibers in the passage and directing treatment radiation pulses along the fibers, one at a time, to generate a shock wave and hydrodynamics flows that strike and emulsify the occlusions. A preferred application is the removal of blood clots (thrombin and embolic) from small cerebral vessels to reverse the effects of an ischemic stroke. The operating parameters and techniques are chosen to minimize the amount of heating of the fragile cerebral vessel walls occurring during this photo acoustic treatment. One such technique is the optical monitoring of the existence of hydrodynamics flow generating vapor bubbles when they are expected to occur and stopping the heat generating pulses propagated along an optical fiber that is not generating such bubbles.

  18. A study of functional outcomes following implantation of a total distal radioulnar joint prosthesis.

    Science.gov (United States)

    Laurentin-Pérez, L A; Goodwin, A N; Babb, B A; Scheker, L R

    2008-02-01

    This paper reports a long-term follow-up measuring pain, range of motion and weight-bearing ability, following implantation of a total distal radioulnar joint prosthesis. This prosthesis differs from excision arthroplasties and ulnar head replacements by replacing all three components of the distal radioulnar joint, viz. the sigmoid notch, the ulnar head and the triangular fibrocartilage. The design allows longitudinal migration of the radius throughout pronation and supination, as well as load bearing of the wrist. Thirty-one patients receiving the prosthesis returned or were interviewed by telephone at a mean of 5.9 (range 4-9) years. Pronation increased from a mean of 65.5 degrees (range 5-90 degrees ) to 74 degrees (range 20-90 degrees ) and supination from 53 degrees (range 5-90 degrees ) to 70 degrees (range 20-90 degrees ) while greatly diminishing and/or eliminating pain. Grip increased from a mean of 10 kg (22 lbs) to 24 kg (52 lbs). Weight bearing was restored or increased in 29 of 31 patients.

  19. Photoacoustic imaging of blood vessels in tissues

    Science.gov (United States)

    de Mul, Frits F. M.; Pilatou, Magdalena C.; Kolkman, Roy G. M.; Hondebrink, Erwin; Steenbergen, Wiendelt

    2002-10-01

    To localize and monitor the blood content in tissue we developed very sensitive photoacoustical detectors. In these detectors a PVdF-layer has been used as piezo-electric material and also fibers for the illumination of the sample are integrated. The resolution is about 20 im in depth and about 50-100 im laterally. The wavelengths ofthe laser light were 532and 1064 nm. With these colors we can measure at different depths in tissue. We will report measurements on real tissue: vessels in chicken breast, in the human arm, and in test animals at various positions.

  20. Dental restoration with endosseous implants after mandibular reconstruction using a fibula free flap and TMJ prosthesis: a patient report.

    Science.gov (United States)

    Infante-Cossio, Pedro; Torres-Lagares, Daniel; Martinez-de-Fuentes, Rafael; Garcia-Perla-Garcia, Alberto; Gutierrez-Perez, Jose-Luis

    2006-01-01

    This patient report describes the secondary reconstruction of a hemimandibular and condylar defect and the dental restoration of a 56-year-old woman who had been subjected to radical ablative surgery 30 years earlier to remove a tumor. In the first phase, a fibula free flap was used in combination with a total TMJ prosthesis for the reconstruction of the hemimandible and condyle. Secondly, 3 endosseous implants were placed in the residual mandible. These implants were used to support an overdenture prosthesis that has remained in continuous function for a period of 2 years.

  1. The Argus™ II retinal prosthesis: factors affecting patient selection for implantation.

    Science.gov (United States)

    Ahuja, Ashish Kishore; Behrend, Matthew R

    2013-09-01

    The Argus II epiretinal prosthesis has been developed to provide partial restoration of vision to subjects blinded from outer retinal degenerative disease. To date, the device has been implanted in multiple subjects with profound retinitis pigmentosa as part of a worldwide clinical feasibility study (clinicaltrials.gov ID: NCT00407602). The Argus II is intended to provide partial restoration of functional vision. Most subjects showed an improvement in tasks assessing orientation & mobility, spatial-motor localization, and ability of discerning the direction of motion of moving stimuli. Roughly one third of subjects experienced measurable improvement in visual acuity with the implant. Some subjects identified words with high accuracy, a result that has also been reported by the leading subretinal implant group. Perceptual threshold was correlated with electrode-retina distance, electrode-fovea distance, and light sensitivity, either as single variables or in bivariate linear regression. Taken together these three variables may be used to inform patient selection and develop algorithms for the fitting of higher-electrode count systems. Visual acuity for future generations of the Argus implant may not hit theoretical limitations until arrays hold an excess of several hundreds of electrodes. Nevertheless, preliminary safety and efficacy data are supportive of the development of higher-resolution systems that target macular placement from implant design and surgical perspectives.

  2. [Nitroxidergic nerve fibers of intracerabral blood vessels].

    Science.gov (United States)

    Kotsiuba, A E; Kotsiuba, E P; Chertok, V M

    2009-01-01

    Methods of light and electron microscopic histochemistry were applied to study the structure and distribution of NADPH-diaphorase-positive neurons and processes in the parietal area of rat cerebral cortex. It was found that the most of the neurons displayed close connections with the intracerebral vessels. In the cerebral cortex, the smallest distance between the axonal plasma membrane and smooth muscle cells of the intracerebral arteries was found to be no less than 0.3-0.5 microm. Neuronal cell bodies were located in the functionally important areas of the vessels (in the areas of lateral trunk branching and in arteriolar sources), while their processes accompanied the vessels, tightly embracing them with their branches. Quite often, the neurons, the dendrites of which make contacts with the bodies or processes of over- or underlying neurons, sent their nerve fibers to the arteries, veins and capillaries. Thus, nitroxidergic neurons or their groups may control the blood flow in the different areas of vascular bed, performing the functions of the local nerve center.

  3. Prosthesis-guided implant restoration of an auricular defect using computed tomography and 3-dimensional photographic imaging technologies: a clinical report.

    Science.gov (United States)

    Wang, Shuming; Leng, Xu; Zheng, Yaqi; Zhang, Dapeng; Wu, Guofeng

    2015-02-01

    The concept of prosthesis-guided implantation has been widely accepted for intraoral implant placement, although clinicians do not fully appreciate its use for facial defect restoration. In this clinical report, multiple digital technologies were used to restore a facial defect with prosthesis-guided implantation. A simulation surgery was performed to remove the residual auricular tissue and to ensure the correct position of the mirrored contralateral ear model. The combined application of computed tomography and 3-dimensional photography preserved the position of the mirrored model and facilitated the definitive implant-retained auricular prosthesis.

  4. Tissue Engineering of Blood Vessels: Functional Requirements, Progress, and Future Challenges.

    Science.gov (United States)

    Kumar, Vivek A; Brewster, Luke P; Caves, Jeffrey M; Chaikof, Elliot L

    2011-09-01

    Vascular disease results in the decreased utility and decreased availability of autologus vascular tissue for small diameter (engineered replacement vessels represent an ideal solution to this clinical problem. Ongoing progress requires combined approaches from biomaterials science, cell biology, and translational medicine to develop feasible solutions with the requisite mechanical support, a non-fouling surface for blood flow, and tissue regeneration. Over the past two decades interest in blood vessel tissue engineering has soared on a global scale, resulting in the first clinical implants of multiple technologies, steady progress with several other systems, and critical lessons-learned. This review will highlight the current inadequacies of autologus and synthetic grafts, the engineering requirements for implantation of tissue-engineered grafts, and the current status of tissue-engineered blood vessel research.

  5. Application of Computational Physics: Blood Vessel Constrictions and Medical Infuses

    CERN Document Server

    Suprijadi,; Subekti, Petrus; Viridi, Sparisoma

    2013-01-01

    Application of computation in many fields are growing fast in last two decades. Increasing on computation performance helps researchers to understand natural phenomena in many fields of science and technology including in life sciences. Computational fluid dynamic is one of numerical methods which is very popular used to describe those phenomena. In this paper we propose moving particle semi-implicit (MPS) and molecular dynamics (MD) to describe different phenomena in blood vessel. The effect of increasing the blood pressure on vessel wall will be calculate using MD methods, while the two fluid blending dynamics will be discussed using MPS. Result from the first phenomenon shows that around 80% of constriction on blood vessel make blood vessel increase and will start to leak on vessel wall, while from the second phenomenon the result shows the visualization of two fluids mixture (drugs and blood) influenced by ratio of drugs debit to blood debit. Keywords: molecular dynamic, blood vessel, fluid dynamic, movin...

  6. Teeth movement in denture and implant-supported prosthesis influenced by microwave flask systems

    Science.gov (United States)

    Consani, Rafael L.X.; Sonehara, Leonardo G.; Mesquita, Marcelo F.; Barão, Valentim A.R.; Caetano, Conrado R.

    2015-01-01

    Background/Aims This study evaluated the teeth movement in maxillary dentures and mandibular implantsupported prostheses processed by microwave flasks. Methods A model mounted on articulator was used to manufacture Co-Cr frameworks. Pins were placed for measurements on the incisal edge of upper and lower central incisors (I), buccal cusp of first upper and lower premolars (PM), and mesiobuccal cusps of upper and lower second molars (M). Distances I-I (incisor to incisor), PM-PM (premolar to premolar), M-M (molar to molar), RI-RM (right incisor to right molar), and LI-LM (left incisor to left molar) were measured before and after processing using a microscope (0.0005 mm). Vertical misfit between abutment and implant platform was evaluated for regions A (left distal implant), B (left median implant), C (medial implant), D (right median implant), and E (right distal implant) in predetermined labial and lingual sites. Prostheses were divided into groups G1 – conventional flask, and G2 – experimental HH flask. Acrylic resin was microwaved at 1400 W (30% for 3 min, 0% for 3 min, and 60% for 3 min). Horizontal teeth displacement and vertical misfit between abutment and implant platform were considered before and after procedures. Data were submitted to three-way ANOVA and Tukey's test (α = 0.05). Results Except for M-M distance, the teeth showed displacements without statistical difference for prosthesis and flask factors. There was no significant difference for vertical misfit values for both flasks. Conclusion Diferente flasks did not cause significant changes in the teeth displacement, except for M-M. Vertical misfit values were not influenced by the flasks. PMID:26605143

  7. Cementable implant-supported prosthesis, serial extraction, and serial implant installation: case report.

    Science.gov (United States)

    Rosen, Harry; Gornitsky, Mervyn

    2004-12-01

    Cement-retained implant-supported prostheses are particularly indicated where access for screw placement is limited or impossible like in posterior locations or where there is limited jaw opening. The patient in this case report suffered from limited jaw opening as a result of a long history of temporomandibular joint ankylosis related to hemophilia. Cement-retained implant-supported prostheses coupled with serial extraction, serial implant installations, and chairside provisional restorations made uneventful treatment possible.

  8. Osseocutaneous integration of an intraosseous transcutaneous amputation prosthesis implant used for reconstruction of a transhumeral amputee: case report.

    Science.gov (United States)

    Kang, Norbert V; Pendegrass, Catherine; Marks, Linda; Blunn, Gordon

    2010-07-01

    Exoprosthetic replacement with an artificial limb is the main option for reconstruction after traumatic amputation of an upper limb. Direct skeletal attachment using an osseointegrated implant improves the ease of fixation of the exoprosthesis to the amputation stump. We now report the use of an intraosseous transcutaneous amputation prosthesis that is designed to achieve osseocutaneous integration. Osseocutaneous integration differs from osseointegration because the aim is to create a stable interface among the implant, the bone, and the soft tissues. This reduces the risk of soft tissue infection and troublesome discharge, which are problems encountered with current osseointegrated implants that focus largely on the bone-implant interface. We describe our experience with an intraosseous transcutaneous amputation prosthesis in a case of transhumeral amputation with 2 years of follow-up.

  9. An implantable blood pressure and flow transmitter.

    Science.gov (United States)

    Rader, R. D.; Meehan, J. P.; Henriksen, J. K. C.

    1973-01-01

    A miniature totally implantable FM/FM telemetry system has been developed to simultaneously measure blood pressure and blood flow, thus providing an appreciation of the hemodynamics of the circulation to the entire body or to a particular organ. Developed for work with animal subjects, the telemetry system's transmission time is controlled by an RF signal that permits an operating life of several months. Pressure is detected by a miniature intravascular transducer and flow is detected by an extravascular interferometric ultrasonic technique. Both pressure and flow are calibrated prior to implanting. The pressure calibration can be checked after the implanting by cannulation; flow calibration can be verified only at the end of the experiment by determining the voltage output from the implanted sensing system as a function of several measured flow rates. The utility of this device has been established by its use in investigating canine renal circulation during exercise, emotional encounters, administration of drugs, and application of accelerative forces.

  10. Patient’s satisfaction after 2-piece inflatable penile prosthesis implantation: An Italian multicentric study

    Directory of Open Access Journals (Sweden)

    Giorgio Gentile

    2016-03-01

    Full Text Available Introduction: Penile prosthesis implant represents a valuable solution for pts with severe erectile dysfunction (ED, non-responders to medical management. The aim of our study was to evaluate the satisfaction of patients (pts after 2-pieces inflatable penile prosthesis (IPP. Aim of the study: to evaluate safety, reliability and post-operative patient’s satisfaction after implantation of two-pieces IPP. Materials and Methods: This retrospective multicentric analysis concerns a group of 42 patients undergone 2-pieces IPP implantation from November 2005 to November 2013, in four Centers of proven experience. As a first step, a detailed review of all clinical reports was performed. Secondly, every patient was asked to fill the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS specifically modified, in order to assess their own satisfaction after surgery and, its impact on patient’s quality of sexual life. Results: 42 pts were evaluated (AMS-Ambicor: 28; Coloplast- Excell: 14; mean age, at time of operation: 60,7 years; mean follow up: 27,6 months; etiology of ED: vascular 23,8%, diabetes 19%, La Peyronie D. 7,1%, consequence of radical prostatectomy 31%, consequence of other pelvic surgery 11,9%, spinal trauma 7%. Mean operative time: 117 ± 58 min, mean postoperative hospital stay 3 ± 1,6 days. Post operative short-term complications: 4 pts (9,5%. Post operative long-term complications: 4 pts (9,5%. Long-term functional results (Questionnaire: 71% of pts (30 reported regular use of the prosthesis, at least 1 time/week, the satisfaction was good in 42% of pts (18, quite good in 33,3% (14, quite bad in 2,4% (1, very bad in 7,1% (3, 6 pts (14,4% didn’t answer. Conclusions: 2 pieces IPP appears to be associated with a low complication rate and good satisfaction of pts especially in the elderly. It also assures satisfactory rates of aesthetics and functional results.

  11. BLOOD FLOW AND MACROMOLECULAR TRANSPORT IN CURVED BLOOD VESSELS

    Institute of Scientific and Technical Information of China (English)

    WEI Lan; WEN Gong-bi; TAN Wen-chang

    2006-01-01

    A numerical analysis of the steady/pulsatile flow and macromolecular (such as LDL and Albumin) transport in curved blood vessels was carried out. The computational results predict that the vortex of the secondary flow is time-dependent in the aortic arch.The concentration of macromolecule concentrates at the region of sharp curve, and the wall concentration at the outer part is higher than that at the inner part. Atherosclerosis and thrombosis are prone to develop in such regions with sharp flow.

  12. Microfabrication of an Implantable silicone Microelectrode array for an epiretinal prosthesis

    Energy Technology Data Exchange (ETDEWEB)

    Maghribi, M

    2003-06-10

    Millions of people suffering from diseases such as retinitis pigmentosa and macular degeneration are legally blind due to the loss of photoreceptor function. Fortunately a large percentage of the neural cells connected to the photoreceptors remain viable, and electrical stimulation of these cells has been shown to result in visual perception. These findings have generated worldwide efforts to develop a retinal prosthesis device, with the hope of restoring vision. Advances in microfabrication, integrated circuits, and wireless technologies provide the means to reach this challenging goal. This dissertation describes the development of innovative silicone-based microfabrication techniques for producing an implantable microelectrode array. The microelectrode array is a component of an epiretinal prosthesis being developed by a multi-laboratory consortium. This array will serve as the interface between an electronic imaging system and the human eye, directly stimulating retinal neurons via thin film conducting traces. Because the array is intended as a long-term implant, vital biological and physical design requirements must be met. A retinal implant poses difficult engineering challenges due to the size of the intraocular cavity and the delicate retina. Not only does it have to be biocompatible in terms of cytotoxicity and degradation, but it also has to be structurally biocompatible, with regard to smooth edges and high conformability; basically mimicking the biological tissue. This is vital to minimize stress and prevent physical damage to the retina. Also, the device must be robust to withstand the forces imposed on it during fabrication and implantation. In order to meet these biocompatibility needs, the use of non-conventional microfabrication materials such as silicone is required. This mandates the enhancement of currently available polymer-based fabrication techniques and the development of new microfabrication methods. Through an iterative process, devices

  13. Design of a radio-linked implantable cochlear prosthesis using surface acoustic wave devices.

    Science.gov (United States)

    Jeutter, D C; Josse, F

    1993-01-01

    Cochlear prosthesis systems for postlingually deaf individuals (those who have become deaf due to disease or injury after having developed mature speech capability) are considered. These systems require the surgical implantation of an array of electrodes within the cochlea and are driven by processed sound signals from outside the body. A system that uses an analog signal approach for transcutaneous transfer of six processed speech data channels using frequency multiplexing is described. The system utilizes a filterbank of six narrowband surface acoustic wave (SAW) filters in the range 72-78 MHz with a 1.2-MHz channel spacing to multiplex the six carrier signals, frequency modulated, by the processed speech signals, onto a composite signal. The same SAW filters are used in the receiver filterbank for signal separation, but are housed in a miniaturized package. The system includes a portable transmitter and a receiver package which is to be implanted in the patient. The implanted circuits are supplied exclusively from power transferred from outside the body via a separate 10-MHz transcutaneous link.

  14. Carbon-carbon composites for orthopedic prosthesis and implants. CRADA final report

    Energy Technology Data Exchange (ETDEWEB)

    Burchell, T D; Klett, J W; Strizak, J P [Oak Ridge National Lab., TN (United States); Baker, C [FMI, Biddeford, ME (United States)

    1998-01-21

    The prosthetic implant market is extensive. For example, because of arthritic degeneration of hip and knee cartilage and osteoporotic fractures of the hip, over 200,000 total joint replacements (TJRs) are performed in the United States each year. Current TJR devices are typically metallic (stainless steel, cobalt, or titanium alloy) and are fixed in the bone with polymethylacrylate (PMMA) cement. Carbon-carbon composite materials offer several distinct advantages over metals for TJR prosthesis. Their mechanical properties can be tailored to match more closely the mechanical properties of human bone, and the composite may have up to 25% porosity, the size and distribution of which may be controlled through processing. The porous nature of carbon-carbon composites will allow for the ingrowth of bone, achieving biological fixation, and eliminating the need for PMMA cement fixation.

  15. Bone marrow blood vessels: normal and neoplastic niche

    Directory of Open Access Journals (Sweden)

    Saeid Shahrabi

    2016-11-01

    Full Text Available Blood vessels are among the most important factors in the transport of materials such as nutrients and oxygen. This study will review the role of blood vessels in normal bone marrow hematopoiesis as well as pathological conditions like leukemia and metastasis. Relevant literature was identified by a Pubmed search (1992-2016 of English-language papers using the terms bone marrow, leukemia, metastasis, and vessel. Given that blood vessels are conduits for the transfer of nutrients, they create a favorable situation for cancer cells and cause their growth and development. On the other hand, blood vessels protect leukemia cells against chemotherapy drugs. Finally, it may be concluded that the vessels are an important factor in the development of malignant diseases.

  16. A novel microporous polyurethane vascular graft: in vivo evaluation of the UTA prosthesis implanted as infra-renal aortic substitute in dogs.

    Science.gov (United States)

    Marois, Y; Akoum, A; King, M; Guidoin, R; von Maltzahn, W; Kowligi, R; Eberhart, R C; Teijeira, F J; Verreault, J

    1993-01-01

    A novel microporous polyurethane blood conduit developed at the University of Texas at Arlington was implanted as an infra-renal substitute in dogs. The prosthesis was fabricated by precipitating a solution of the polymer with dry nitrogen onto a rotating mandrel. The grafts were sterilized either by gamma radiation (series I) or ethylene oxide (series II); they were implanted for the following prescheduled periods: 4, 24, 48 hours, and 1 week (short-term) and 2, 4 weeks, 3 and 6 months (medium-term). The thrombohematological characteristics of each animal were evaluated prior to implantation and confirmed that the index of blood coagulability was normal. In the short-term group, five out of eight grafts were patent and three were partially occluded; four grafts in the medium-term group were patent; one was partially occluded; and three were thrombosed at retrieval. One week after implantation, the prostheses were surrounded by an external capsule, which was present mainly at the two anastomoses. The external capsule covered the entire graft at 3 months. No kinking of the grafts was observed and the presence of a mild yellow stain related to bilirubin uptake was detected at 2 weeks, 1, 3, and 6 months. Histological studies have revealed the formation of a thin internal capsule at both anastomoses, 2 weeks postimplantation, which was not anchored to the graft wall. In the medium-term group, the thrombosed grafts failed to develop an internal capsule, whereas the patent graft exhibited a thick internal capsule made of neocollagenous tissue over the entire graft. This new microporous polyurethane prosthesis did not perform satisfactorily as an infra-renal substitute in dogs and its in vivo stability requires further assessment. Thus, the concept of a polyurethane with closed pores does not achieve what was anticipated.

  17. Erectile dysfunction patients are more satisfied with penile prosthesis implantation compared with tadalafil and intracavernosal injection treatments.

    Science.gov (United States)

    Kucuk, E V; Tahra, A; Bindayi, A; Onol, F F

    2016-09-01

    There are various treatment modalities for erectile dysfunction with different success and satisfaction rates. We aim to compare patient satisfaction with tadalafil, intracavernosal injection, and penile prosthesis implantation in patients with erectile dysfunction. The records of 3448 men with erectile dysfunction were evaluated retrospectively. A total of 356 men with organic erectile dysfunction were enrolled into this study. Of these patients, 132 (37%) received tadalafil 20 mg twice a week for 12 weeks, 106 (30%) patients received tadalafil 5 mg once-daily for 12 weeks, 96 (27%) patients used intracavernosal injection therapy (Bi-mix; papaverine and phentolamine). Moreover, 22 patients underwent penile prosthesis implantation. Patient and partner satisfaction were assessed with International Index of Erectile Function (IIEF) and Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) questionnaire. Patients' mean age was 52.4 ± 25.76 (32-71). The etiology of erectile dysfunction was chronic systemic diseases in 133 (44%) and radical prostatectomy in 121 patients (40%). The mean IIEF-5 scores improvement after the treatment was higher in penile prosthesis implantation group (12.4 ± 1.3) compared with tadalafil 5 mg (6.7 ± 1.5) (p prosthesis implantation group (78.2 ± 11.3) compared with intracavernosal injection (60.3 ± 6.3), tadalafil 5 mg (72.5 ± 4.5), and tadalafil 20 mg 70.7 ± 3.4 groups (p prosthesis implantation group, 50.2 ± 1.5 in intracavernosal injection group, 62.9 ± 7.8 in tadalafil 5 mg, and 61.3 ± 5.3 in tadalafil 20 mg group (p prosthesis implantation seem to be more satisfied compared with tadalafil treatment and intracavernosal injection. Future clinical trials are warranted to confirm our results.

  18. A 6-year Evaluation of 223 Tapered Dental Implants and associated prosthesis in 92 patients at a University Hospital.

    Science.gov (United States)

    Nagi, Sana Ehsen; Khan, Farhan Raza; Ali, Rabia

    2016-10-01

    The aim of the retrospective study was to assess the clinical and radiographic outcome of the dental implant surgery and prosthetics. It was conducted at the Aga Khan University Hospital, Karachi, and comprised of medical charts and radiographic records of patients visiting between 2010 and 2015. Variables such as implant dimensions, final prosthesis, method of retention, loading protocol and patient factors were analysed. A total of 223 implants (143(64.1%) in maxilla and 80(35.9%) in mandible) were placed in 92 subjects (50(54.3%) males and 42(45.7%) females). All implants were Zimmer tapered screw-vent. Length of 108(48.4%) implants was 11.5mm and diameter of 84(37.7%) implants was 4.7mm. Besides, 6(2.7%) implants failed to osseointegrate, whereas 1(0.4%) implant failed at 12 months of loading. Among the 216(96.9%) successful implants, 140(64.8%) served as bridge abutments, 72(33.3%) were single crown abutments and 4(1.9%) were overdenture abutments. Also, 37(17.1%) implants were immediately loaded. The six-year survival rate of implants was 96.9%.

  19. Heritability of retinal vessel diameters and blood pressure

    DEFF Research Database (Denmark)

    Taarnhøj, Nina C B B; Larsen, Michael; Sander, Birgit

    2006-01-01

    PURPOSE: To assess the relative influence of genetic and environmental effects on retinal vessel diameters and blood pressure in healthy adults, as well as the possible genetic connection between these two characteristics. METHODS: In 55 monozygotic and 50 dizygotic same-sex healthy twin pairs......%-80%) for CRAE, 83% (95% CI: 73%-89%) for CRVE, and 61% (95% CI: 44%-73%) for mean arterial blood pressure (MABP). Retinal artery diameter decreased with increasing age and increasing arterial blood pressure. Mean vessel diameters in the population were 165.8 +/- 14.9 microm for CRAE, 246.2 +/- 17.7 microm...... and blood glucose, variations in retinal blood vessel diameters and blood pressure were predominantly attributable to genetic effects. A genetic influence may have a role in individual susceptibility to hypertension and other vascular diseases. The results suggest that retinal vessel diameters...

  20. Detection and measurement of retinal blood vessel pulsatile motion

    Science.gov (United States)

    Xiao, Di; Frost, Shaun; Vignarajan, Janardhan; An, Dong; Tay-Kearney, Mei-Ling; Kanagasingam, Yogi

    2016-03-01

    Retinal photography is a non-invasive and well-accepted clinical diagnosis of ocular diseases. Qualitative and quantitative assessment of retinal images is crucial in ocular diseases related clinical application. Pulsatile properties caused by cardiac rhythm, such as spontaneous venous pulsation (SVP) and pulsatile motion of small arterioles, can be visualized by dynamic retinal imaging techniques and provide clinical significance. In this paper, we aim at vessel pulsatile motion detection and measurement. We proposed a novel approach for pulsatile motion measurement of retinal blood vessels by applying retinal image registration, blood vessel detection and blood vessel motion detection and measurement on infrared retinal image sequences. The performance of the proposed methods was evaluated on 8 image sequences with 240 images. A preliminary result has demonstrated the good performance of the method for blood vessel pulsatile motion observation and measurement.

  1. Orthodontic Microimplants Assisted Intrusion of Supra-erupted Maxillary Molar Enabling Osseointegrated Implant Supported Mandibular Prosthesis: Case Reports.

    Science.gov (United States)

    Rai, Deepak; Bhasin, Saranjeet Singh; Rai, Sheetal

    2014-12-01

    Loss of mandibular molars, when not replaced in time, are usually associated with overeruption of maxillary molars. To provide prosthetic replacement for missing lower posteriors, over erupted maxillary teeth have been intruded in past with great difficulty in adults with conventional orthodontics, along with associated problems of root resorption. Currently orthodontic microimplants provide stable intraoral anchorage, allow predictable maxillary molar intrusion enabling reestablishment of functional posterior occlusion with mandibular implant supported prosthesis, thereby reducing need for prosthetic crown reduction in maxillary arch. The added advantage of microimplant is it enables use of sectional appliance in area of concern instead of full arch bracketed appliance which an adult may not accept. The case reports demonstrates, overerupted maxillary molars were intruded using orthodontic microimplants to enable prosthetic rehabilitation of mandibular dentition by osseointegrated implant supported prosthesis. The second case report also demonstrates use of CBCT scan in planning and execution.

  2.  Evaluation of the humoral and cellular immune responses after implantation of a PTFE vascular prosthesis

    Directory of Open Access Journals (Sweden)

    Jan Skóra

    2012-07-01

    Full Text Available  Introduction:The experiment was designed in order to determine the immunological processes that occur during the healing in synthetic vascular grafts, especially to establish the differences in the location of the complement system proteins between the proximal and distal anastomosis and the differences in the arrangement of inflammatory cells in those anastomoses. The understanding of those processes will provide a true basis for determining risk factors for complications after arterial repair procedures.Material/Methods:The experiment was carried out on 16 dogs that underwent implantation of unilateral aorto-femoral bypass with expanded polytetrafluoroethylene (ePTFE. After 6 months all animals were euthanized to dissect the vascular grafts. Immunohistochemical assays and electron microscopic examinations were performed.Results:Immunohistochemical findings in the structure of neointima between anastomoses of vascular prostheses demonstrated significant differences between humoral and cellular responses. The area of proximal anastomosis revealed the presence of fibroblasts, but no macrophages were detected. The histological structure of the proximal anastomosis indicates that inflammatory processes were ended during the prosthesis healing. The immunological response obtained in the distal anastomosis corresponded to the chronic inflammatory reaction with the presence of macrophages, myofibroblasts and deposits of complement C3.Discussion:The identification of differences in the presence of macrophages and myofibroblasts and the presence of the C3 component between the anastomoses is the original achievement of the present study. In the available literature, no such significant differences have been shown so far in the humoral and cellular immune response caused by the presence of an artificial vessel in the arterial system.

  3. Autoinflation Leading to Failure of Two-Piece Ambicor Implantable Penile Prosthesis: An Outcome from a Methodical Treatment of Recalcitrant Stuttering Priapism

    Directory of Open Access Journals (Sweden)

    R. Charles Welliver

    2014-01-01

    Full Text Available Introduction. We present the case of a patient who received a two-piece Ambicor penile prosthesis for idiopathic recurrent “stuttering” priapism refractory to other treatment options. The patient returned unable to deflate the device due to an interesting anatomically induced mechanical failure. Aims. To describe the method and findings of this inflatable prosthesis failure. Results. Prosthesis failure occurred due to restrictive corporal diameter and the unique characteristics of fluid reservoir location in the two-piece inflatable prosthesis. The patient was successfully converted to a semirigid prosthesis with resolution of the pain that was due to his prosthesis autoinflation. Conclusion. Stuttering priapism remains a challenging clinical problem. Penile implantation is a reasonable long-term solution in a patient refractory to less invasive options. In patients with fibrotic corpora, a malleable device should be considered (at least temporarily if unable to dilate comfortably to 13 mm.

  4. Lattice BGK Simulations of the Blood Flow in Elastic Vessels

    Institute of Scientific and Technical Information of China (English)

    LU Xiao-Yang; YI Hou-Hui; CHEN Ji-Yao; FANG Hai-Ping

    2006-01-01

    @@ The lattice Boltzmann method is applied to study the flow in elastic blood vessels. The volume-flow rate increases considerably when the compliance constant of the blood vessel is below a critical value. There is a region of the compliance constant in which the average volume-flow rate is dramatically enhanced. A harmonic perturbation of the pressure does not change the behaviour of the average volume-flow rate while the harmonic wave attenuates very quickly along the tube when the resonant period is close to that of the input wave. The model, together with the simulation results, is expected to be helpful to understand the mechanism of the blood volume-flow rate related to the compliance constant of the blood vessel, especially on the dependence of the flux of human blood vessel under weather changes, which has medical significance.

  5. Instability and "Sausage-String" Appearance in Blood Vessels during High Blood Pressure

    CERN Document Server

    Alstrøm, P; Colding-Jorgensen, M; Gustafsson, F; Holstein-Rathlou, N H; Alstrom, Preben; Eguiluz, Victor M.; Colding-Jorgensen, Morten; Gustafsson, Finn; Holstein-Rathlou, Niels-Henrik

    1999-01-01

    A new Rayleigh-type instability is proposed to explain the `sausage-string' pattern of alternating constrictions and dilatations formed in blood vessels under influence of a vasoconstricting agent. Our theory involves the nonlinear elasticity characteristics of the vessel wall, and provides predictions for the conditions under which the cylindrical form of a blood vessel becomes unstable.

  6. Rehabilitation of an Infected Eye with an Acrylic Ball Implant and a Custom made Scleral Ocular Prosthesis.

    Science.gov (United States)

    Anantharaju, Abhilash; Kamath, Giridhar; Rao K, Suhas; Naik, Deepak S

    2013-09-01

    This clinical report describes the prosthetic rehabilitation of a patient with corneal abscess with endophthalmitis of the left eye. Infection with a history of trauma resulted in loss of vision but with intact eye ball movements. Cornea excising evisceration was carried out following placement of poly(methyl methacrylate) ocular ball implant. Later custom made scleral prosthesis was fabricated to maintain functional integrity of the socket and to satisfy patient's aesthetic needs.

  7. Tissue engineering of blood vessels with endothelial cells differentiated from mouse embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    ZHEN XU; MIN XIONG SHEN; DONG ZHU MA; LI YING WANG; XI LIANG ZHA

    2003-01-01

    Endothelial cells (TEC3 cells) derived from mouse embryonic stem (ES) cells were used as seed cells to construct blood vessels. Tissue engineered blood vessels were made by seeding 8 × l06 smooth muscle cells (SMCs) obtained from rabbit arteries onto a sheet of nonwoven polyglycolic acid (PGA) fibers, which was used as a biodegradable polymer scaffold. After being cultured in DMEM medium for 7 days in vitro, SMCs grew well on the PGA fibers, and the cell-PGA sheet was then wrapped around a silicon tube, and implanted subcutaneously into nude mice. After 6~8 weeks, the silicon tube was replaced with another silicon tube in smaller diameter, and then the TEC3 cells (endothelial cells differentiated from mouse ES cells) were injected inside the engineered vessel tube as the test group. In the control group only culture medium was injected. Five days later, the engineered vessels were harvested for gross observation, histological and immunohistochemical analysis. The preliminary results demonstrated that the SMC-PGA construct could form a tubular structure in 6~8 weeks and PGA fibers were completely degraded. Histological and immunohistochemical analysis of the newly formed tissue revealed a typical blood vessel structure, including a lining of endothelial cells (ECs) on the lumimal surface and the presence of SMC and collagen in the wall. No EC lining was found in the tubes of control group. Therefore, the ECs differentiated from mouse ES cells can serve as seed cells for endothelium lining in tissue engineered blood vessels.

  8. Automated blood vessel extraction using local features on retinal images

    Science.gov (United States)

    Hatanaka, Yuji; Samo, Kazuki; Tajima, Mikiya; Ogohara, Kazunori; Muramatsu, Chisako; Okumura, Susumu; Fujita, Hiroshi

    2016-03-01

    An automated blood vessel extraction using high-order local autocorrelation (HLAC) on retinal images is presented. Although many blood vessel extraction methods based on contrast have been proposed, a technique based on the relation of neighbor pixels has not been published. HLAC features are shift-invariant; therefore, we applied HLAC features to retinal images. However, HLAC features are weak to turned image, thus a method was improved by the addition of HLAC features to a polar transformed image. The blood vessels were classified using an artificial neural network (ANN) with HLAC features using 105 mask patterns as input. To improve performance, the second ANN (ANN2) was constructed by using the green component of the color retinal image and the four output values of ANN, Gabor filter, double-ring filter and black-top-hat transformation. The retinal images used in this study were obtained from the "Digital Retinal Images for Vessel Extraction" (DRIVE) database. The ANN using HLAC output apparent white values in the blood vessel regions and could also extract blood vessels with low contrast. The outputs were evaluated using the area under the curve (AUC) based on receiver operating characteristics (ROC) analysis. The AUC of ANN2 was 0.960 as a result of our study. The result can be used for the quantitative analysis of the blood vessels.

  9. A Computational Model Predicting Disruption of Blood Vessel Development

    Science.gov (United States)

    Vascular development is a complex process regulated by dynamic biological networks that vary in topology and state across different tissues and developmental stages. Signals regulating de novo blood vessel formation (vasculogenesis) and remodeling (angiogenesis) come from a varie...

  10. Synthesis of cobalt alloy through smelting method and its characterization as prosthesis bone implant

    Energy Technology Data Exchange (ETDEWEB)

    Aminatun,, E-mail: ami-sofijan@yahoo.co.id; Putri, N.S Efinda, E-mail: ami-sofijan@yahoo.co.id; Indriani, Arista, E-mail: ami-sofijan@yahoo.co.id; Himawati, Umi, E-mail: ami-sofijan@yahoo.co.id; Hikmawati, Dyah, E-mail: ami-sofijan@yahoo.co.id; Suhariningsih, E-mail: ami-sofijan@yahoo.co.id [Department of physics, Faculty of Science and Technology, Airlangga University (Indonesia)

    2014-09-25

    Cobalt-based alloys are widely used as total hip and knee replacements because of their excellent properties, such as corrosion resistance, fatigue strength and biocompatibility. In this work, cobalt alloys with variation of Cr (28.5; 30; 31.5; 33, and 34.5% wt) have been synthesized by smelting method began with the process of compaction, followed by smelting process using Tri Arc Melting Furnace at 200A. Continued by homogenization process at recrystallization temperature (1250° C) for 3 hours to allow the atoms diffuses and transform into γ phase. The next process is rolling process which is accompanied by heating at 1200° C for ± 15 minutes and followed by quenching. This process is repeated until the obtained thickness of ± 1 mm. The evaluated material properties included microstructure, surface morphology, and hardness value. It was shown that microstructure of cobalt alloys with variation of Cr is dominant by γ phase, thus making the entire cobalt alloys have high hardness. It was also shown from the surface morphology of entire cobalt alloys sample indicated the whole process of synthesis that had good solubility were at flat surface area. Hardness value test showed all of cobalt alloys sample had high hardness, just variation of 33% Cr be in the range of ASTMF75, it were 345,24 VHN which is potential to be applied as an implant prosthesis.

  11. Blood flow changes coincide with cellular rearrangements during blood vessel pruning in zebrafish embryos.

    Directory of Open Access Journals (Sweden)

    Eva Kochhan

    Full Text Available After the initial formation of a highly branched vascular plexus, blood vessel pruning generates a hierarchically structured network with improved flow characteristics. We report here on the cellular events that occur during the pruning of a defined blood vessel in the eye of developing zebrafish embryos. Time-lapse imaging reveals that the connection of a new blood vessel sprout with a previously perfused multicellular endothelial tube leads to the formation of a branched, Y-shaped structure. Subsequently, endothelial cells in parts of the previously perfused branch rearrange from a multicellular into a unicellular tube, followed by blood vessel detachment. This process is accompanied by endothelial cell death. Finally, we show that differences in blood flow between neighboring vessels are important for the completion of the pruning process. Our data suggest that flow induced changes in tubular architecture ensure proper blood vessel pruning.

  12. 人工关节假体植入后无菌性松动的发病机制%Pathogenesis of aseptic prosthesis loosening after artificial prosthesis implantation

    Institute of Scientific and Technical Information of China (English)

    马玉超; 田京

    2012-01-01

    BACKGROUND: There are many clinical researches on aseptic loosening of artificial prosthesis, but the exact pathogenesis is still unclear.OBJECTIVE: To review the pathogenesis of prosthesis aseptic loosening after artificial prosthesis implantation.METHODS: A computer-based online search of PubMed and CNKI was performed to search related articles published between 2006 and 2011 with the key words of “artificial prosthesis, aseptic loosening” both in English and Chinese. A total of 77 articles were obtained, and finally 38 articles were included.RESULTS AND CONCLUSION: Aseptic loosening after long-term total hip replacement is one of the main failure reasons. In the recent years, analysis of revision total hip replacement for failed hip arthroplasty showed that aseptic loosening is the chief reason. The mechanism of aseptic loosening mainly includes mechanical mechanisms, biological and other mechanisms. With further research and the improvement of implantation method and prosthetic materials, aseptic loosening will eventually be minimized, so that the service life of prosthesis will be longer.%背景:对于人工关节无菌性松动的基础和临床研究很多,但其确切机制仍不甚明确.目的:综述人工关节假体植入后无菌性松动的发病机制.方法:由第一作者应用计算机检索PubMed和中国期刊全文数据库2006/2011相关文献.在标题、摘要、关键词中以"artificial prosthesis,aseptic loosening"或"人工关节、无菌性松动"为检索词进行检索.共检索到77篇文献,最终纳入符合标准的文献38篇.结果与结论:无菌性松动已成为人工关节置换后远期失败的主要原因之一.近年来对人工全髋关节置换后翻修病例回顾性分析的统计显示,无菌性松动位于翻修原因第1位.关于人工关节无菌性松动的机制主要分为机械机制、生物机制及其他机制,它们的共同结果是造成骨吸收、骨溶解,最终导致假体松动.随着研究

  13. Robust Retinal Blood Vessel Segmentation Based on Reinforcement Local Descriptions

    Directory of Open Access Journals (Sweden)

    Meng Li

    2017-01-01

    Full Text Available Retinal blood vessels segmentation plays an important role for retinal image analysis. In this paper, we propose robust retinal blood vessel segmentation method based on reinforcement local descriptions. A novel line set based feature is firstly developed to capture local shape information of vessels by employing the length prior of vessels, which is robust to intensity variety. After that, local intensity feature is calculated for each pixel, and then morphological gradient feature is extracted for enhancing the local edge of smaller vessel. At last, line set based feature, local intensity feature, and morphological gradient feature are combined to obtain the reinforcement local descriptions. Compared with existing local descriptions, proposed reinforcement local description contains more local information of local shape, intensity, and edge of vessels, which is more robust. After feature extraction, SVM is trained for blood vessel segmentation. In addition, we also develop a postprocessing method based on morphological reconstruction to connect some discontinuous vessels and further obtain more accurate segmentation result. Experimental results on two public databases (DRIVE and STARE demonstrate that proposed reinforcement local descriptions outperform the state-of-the-art method.

  14. Diffuse light tomography to detect blood vessels using Tikhonov regularization

    Science.gov (United States)

    Kazanci, Huseyin O.; Jacques, Steven L.

    2016-04-01

    Detection of blood vessels within light-scattering tissues involves detection of subtle shadows as blood absorbs light. These shadows are diffuse but measurable by a set of source-detector pairs in a spatial array of sources and detectors on the tissue surface. The measured shadows can reconstruct the internal position(s) of blood vessels. The tomographic method involves a set of Ns sources and Nd detectors such that Nsd = Ns x Nd source-detector pairs produce Nsd measurements, each interrogating the tissue with a unique perspective, i.e., a unique region of sensitivity to voxels within the tissue. This tutorial report describes the reconstruction of the image of a blood vessel within a soft tissue based on such source-detector measurements, by solving a matrix equation using Tikhonov regularization. This is not a novel contribution, but rather a simple introduction to a well-known method, demonstrating its use in mapping blood perfusion.

  15. DETECTION OF BLOOD VESSELS AND MEASUREMENT OF VESSEL WIDTH FOR DIABETIC RETINOPATHY

    Directory of Open Access Journals (Sweden)

    S.Sukanya

    2014-09-01

    Full Text Available The proposed method measures the retinal blood vessel diameter to identify arteriolar narrowing, arteriovenous (AV nicking, branching coefficients to detect early diabetic retinopathy. It utilizes the vessel centerline and edge information to measure the width for a vessel segment. From the input retinal image, the vascular network is extracted using the local entropy thresholding method. The vessel boundaries are extracted using sobel edge detection method. The skeletonization operation is applied to the vascular network and mapping the vessel boundaries and the skeleton image. The branching point detection method is then performed to localize all crossing locations. A rotational invariant mask to search the pixel pairs from the edge image, and calculate the shortest distance pair which provides the vessel width (or diameter for that cross-section. Variation in the width measurement identifies the diabetic retinopathy.

  16. Passive Fit in Screw Retained Multi-unit Implant Prosthesis Understanding and Achieving: A Review of the Literature.

    Science.gov (United States)

    Buzayan, Muaiyed Mahmoud; Yunus, Norsiah Binti

    2014-03-01

    One of the considerable challenges for screw-retained multi-unit implant prosthesis is achieving a passive fit of the prosthesis' superstructure to the implants. This passive fit is supposed to be one of the most vital requirements for the maintenance of the osseointegration. On the other hand, the misfit of the implant supported superstructure may lead to unfavourable complications, which can be mechanical or biological in nature. The manifestations of these complications may range from fracture of various components in the implant system, pain, marginal bone loss, and even loss of osseointegration. Thus, minimizing the misfit and optimizing the passive fit should be a prerequisite for implant survival and success. The purpose of this article is to present and summarize some aspects of the passive fit achieving and improving methods. The literature review was performed through Science Direct, Pubmed, and Google database. They were searched in English using the following combinations of keywords: passive fit, implant misfit and framework misfit. Articles were selected on the basis of whether they had sufficient information related to framework misfit's related factors, passive fit and its achievement techniques, marginal bone changes relation with the misfit, implant impression techniques and splinting concept. The related references were selected in order to emphasize the importance of the passive fit achievement and the misfit minimizing. Despite the fact that the literature presents considerable information regarding the framework's misfit, there was not consistency in literature on a specified number or even a range to be the acceptable level of misfit. On the other hand, a review of the literature revealed that the complete passive fit still remains a tricky goal to be achieved by the prosthodontist.

  17. Non-anatomical implantation of supra-aortic branches for customizing the standard form of Thoraflex™ hybrid prosthesis to a patient's anatomical requirements.

    Science.gov (United States)

    Urbanski, Paul P; Irimie, Vadim; Zembala, Michal

    2016-01-01

    Frozen elephant trunk technique represents a valuable therapeutic option for patients with extensive pathology of thoracic aorta. Thoraflex™ hybrid prosthesis (Vascutek, Terumo, Inchinnan, UK) is one of the commercially available devices in which a stent graft is combined with branched vascular tube mimicking the aortic arch anatomy. Owing to the sewing collar between the stented and unstented portions, this hybrid prosthesis offers a valuable addition to the surgical armamentarium for patients with huge thoracic aorta aneurysms, in whom the aortic diameter exceeds the diameter of available stent grafts. However, the standard factory form of the quadrifurcated arch prosthesis does not always fit to the patient's anatomy and demands a deviation from the anatomical anastomosing of the branches with the respective supra-aortic arteries. A technique of non-anatomical implantation of supra-aortic arteries for customizing the standard form of the Thoraflex prosthesis is described, which facilitates the surgery without limiting the functionality of this hybrid prosthesis.

  18. Implantation of AMS 700 LGX penile prosthesis preserves penile length without the need for penile lengthening procedures

    Directory of Open Access Journals (Sweden)

    Carlo Luigi Augusto Negro

    2016-01-01

    Full Text Available Implantation of an inflatable penile prosthesis (IPP is a well-established definitive solution for erectile dysfunction when conservative treatments fail. Penile implants may shorten the penis. The AMS 700 LGX IPP is in common use but reports on its mechanical reliability, medium-term postsurgical patient satisfaction, and mean penile length preservation are lacking. We investigate the mean penile length, mechanical reliability, and patient satisfaction at 6 and 12 months after implantation of the AMS 700 LGX. This prospective study consecutively enrolled men undergoing first-time IPP implant surgery from February 2009 to April 2012. Stretched flaccid penile length, penile length at 50% and 100% of stiffness (P50 and P100 and International Index of Erectile Function (IIEF and Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS scores, were measured at 6 and 12 months postsurgery. Of 45 patients who underwent AMS 700 LGX implantation (median age 61 years and completed 6 months′ follow-up, 36 (80% completed the study. A significant difference in stretched flaccid penile length was seen between 6 and 12 months (P = 0.033. P100 was also significantly increased at 6 and 12 months, with a mean 10% increase (1.3 ± 0.4 cm from baseline to 12 months. Differences in mean IIEF scores at 6 and 12 months were significant for the desired domain (P = 0.0001 and for overall satisfaction (P = 0.002; however, mean EDITS scores at 6 and 12 months were not significantly improved. AMS 700 LGX is a powerful tool for preserving penile length in men undergoing penile prosthesis implantation.

  19. Implantation of AMS 700 LGX penile prosthesis preserves penile length without the need for penile lengthening procedures.

    Science.gov (United States)

    Negro, Carlo Luigi Augusto; Paradiso, Matteo; Rocca, Alessandro; Bardari, Franco

    2016-01-01

    Implantation of an inflatable penile prosthesis (IPP) is a well-established definitive solution for erectile dysfunction when conservative treatments fail. Penile implants may shorten the penis. The AMS 700 LGX IPP is in common use but reports on its mechanical reliability, medium-term postsurgical patient satisfaction, and mean penile length preservation are lacking. We investigate the mean penile length, mechanical reliability, and patient satisfaction at 6 and 12 months after implantation of the AMS 700 LGX. This prospective study consecutively enrolled men undergoing first-time IPP implant surgery from February 2009 to April 2012. Stretched flaccid penile length, penile length at 50% and 100% of stiffness (P50 and P100) and International Index of Erectile Function (IIEF) and Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) scores, were measured at 6 and 12 months postsurgery. Of 45 patients who underwent AMS 700 LGX implantation (median age 61 years) and completed 6 months' follow-up, 36 (80%) completed the study. A significant difference in stretched flaccid penile length was seen between 6 and 12 months (P = 0.033). P100 was also significantly increased at 6 and 12 months, with a mean 10% increase (1.3 ± 0.4 cm) from baseline to 12 months. Differences in mean IIEF scores at 6 and 12 months were significant for the desired domain (P = 0.0001) and for overall satisfaction (P = 0.002); however, mean EDITS scores at 6 and 12 months were not significantly improved. AMS 700 LGX is a powerful tool for preserving penile length in men undergoing penile prosthesis implantation.

  20. Tracking blood vessels in human forearms using visual servoing

    DEFF Research Database (Denmark)

    Savarimuthu, Thiusius Rajeeth; Ellekilde, Lars-Peter; Hansen, Morten

    compensation. By using images taken with near-infrared light to locate the blood vessels in a human forearm and using the same images to detects movements of the arm, this paper shows that it is possible make a robot arm, potentially equipped with a needle for drawing the blood, compensate for the movements......Drawing an average of more than 2 blood sample per Danish citizen per year increases the demand for an automatic blood sampling method. This paper presents a proof of concept to one of the main challenges in making a fully automated blood sampling procedure, namely: the patient movement...

  1. Silk fibroin microtubes for blood vessel engineering.

    Science.gov (United States)

    Lovett, Michael; Cannizzaro, Christopher; Daheron, Laurence; Messmer, Brady; Vunjak-Novakovic, Gordana; Kaplan, David L

    2007-12-01

    Currently available synthetic grafts demonstrate moderate success at the macrovascular level, but fail at the microvascular scale (steel wire into aqueous silk fibroin, where the addition of poly(ethylene oxide) (PEO) enabled control of microtube porosity. The microtube properties were characterized in terms of pore size, burst strength, protein permeability, enzymatic degradation, and cell migration. Low porosity microtubes demonstrated superior mechanical properties in terms of higher burst pressures, but displayed poor protein permeability; whereas higher porosity tubes had lower burst strengths but increased permeability and enhanced protein transport. The microtubes also exhibited cellular barrier functions as low porosity tubes prevented outward migration of GFP-transduced HUVECs, while the high porosity microtubes allowed a few cells per tube to migrate outward during perfusion. When combined with the biocompatible and suturability features of silk fibroin, these results suggest that silk microtubes, either implanted directly or preseeded with cells, are an attractive biomaterial for microvascular grafts.

  2. Customizable engineered blood vessels using 3D printed inserts.

    Science.gov (United States)

    Pinnock, Cameron B; Meier, Elizabeth M; Joshi, Neeraj N; Wu, Bin; Lam, Mai T

    2016-04-15

    Current techniques for tissue engineering blood vessels are not customizable for vascular size variation and vessel wall thickness. These critical parameters vary widely between the different arteries in the human body, and the ability to engineer vessels of varying sizes could increase capabilities for disease modeling and treatment options. We present an innovative method for producing customizable, tissue engineered, self-organizing vascular constructs by replicating a major structural component of blood vessels - the smooth muscle layer, or tunica media. We utilize a unique system combining 3D printed plate inserts to control construct size and shape, and cell sheets supported by a temporary fibrin hydrogel to encourage cellular self-organization into a tubular form resembling a natural artery. To form the vascular construct, 3D printed inserts are adhered to tissue culture plates, fibrin hydrogel is deposited around the inserts, and human aortic smooth muscle cells are then seeded atop the fibrin hydrogel. The gel, aided by the innate contractile properties of the smooth muscle cells, aggregates towards the center post insert, creating a tissue ring of smooth muscle cells. These rings are then stacked into the final tubular construct. Our methodology is robust, easily repeatable and allows for customization of cellular composition, vessel wall thickness, and length of the vessel construct merely by varying the size of the 3D printed inserts. This platform has potential for facilitating more accurate modeling of vascular pathology, serving as a drug discovery tool, or for vessel repair in disease treatment.

  3. Purinergic signaling and blood vessels in health and disease.

    Science.gov (United States)

    Burnstock, Geoffrey; Ralevic, Vera

    2014-01-01

    Purinergic signaling plays important roles in control of vascular tone and remodeling. There is dual control of vascular tone by ATP released as a cotransmitter with noradrenaline from perivascular sympathetic nerves to cause vasoconstriction via P2X1 receptors, whereas ATP released from endothelial cells in response to changes in blood flow (producing shear stress) or hypoxia acts on P2X and P2Y receptors on endothelial cells to produce nitric oxide and endothelium-derived hyperpolarizing factor, which dilates vessels. ATP is also released from sensory-motor nerves during antidromic reflex activity to produce relaxation of some blood vessels. In this review, we stress the differences in neural and endothelial factors in purinergic control of different blood vessels. The long-term (trophic) actions of purine and pyrimidine nucleosides and nucleotides in promoting migration and proliferation of both vascular smooth muscle and endothelial cells via P1 and P2Y receptors during angiogenesis and vessel remodeling during restenosis after angioplasty are described. The pathophysiology of blood vessels and therapeutic potential of purinergic agents in diseases, including hypertension, atherosclerosis, ischemia, thrombosis and stroke, diabetes, and migraine, is discussed.

  4. Is the daily use of vacuum erection device for a month before penile prosthesis implantation beneficial? a randomized controlled trial.

    Science.gov (United States)

    Canguven, O; Talib, R A; Campbell, J; De Young, L; El Ansari, W; Al-Ansari, A

    2017-01-01

    Patient concerns about penile length after penile prosthesis (PP) implantation for erectile dysfunction (ED) have significant impact on patients and their partners. In addition, corporal fibrosis is associated with difficult PP implantation. The preoperative use of vacuum erectile devices (VED) is an uncommon physical treatment for such concerns. Therefore, the current randomized controlled study assessed two outcomes: whether pre-operative VED use for a month before surgery would significantly increase flaccid stretched penile length (SPL) on the day of surgery, and facilitate easier corporal dilatation intraoperatively. Fifty-one patients scheduled for PP implantation for ED were randomized to either intervention group (pre-operative VED use; 10-15 min/day for ≥30 days; Group A; n = 25), or control group (no intervention; Group B; n = 26). A research assistant (blinded to the treatment assignments) recorded SPL at baseline (initial consultation) and on day of surgery. The surgeons performing the PP implantation (also blinded to the treatment assignments) provided subjective assessments of the ease of corporal dilatation. Baseline patient characteristics, demographics, and comorbidities were the same in both groups. Baseline measurements (SPL-1) were 10.71 ± 1.28 and 10.87 ± 1.26 cm in Group A and Group B, respectively; and the day of surgery measurements (SPL-2) were 11.50 ± 1.33 and 11.06 ± 1.34 cm in Group A and Group B, respectively. In terms of outcomes: mean SPL increase in Group A was significantly more by a mean of 0.80 ± 0.38 cm (p outcomes of penile prosthesis implantation after pre-operative use of vacuum erectile devices.

  5. Podoplanin immunopositive lymphatic vessels at the implant interface in a rat model of osteoporotic fractures.

    Directory of Open Access Journals (Sweden)

    Katrin Susanne Lips

    Full Text Available Insertion of bone substitution materials accelerates healing of osteoporotic fractures. Biodegradable materials are preferred for application in osteoporotic patients to avoid a second surgery for implant replacement. Degraded implant fragments are often absorbed by macrophages that are removed from the fracture side via passage through veins or lymphatic vessels. We investigated if lymphatic vessels occur in osteoporotic bone defects and whether they are regulated by the use of different materials. To address this issue osteoporosis was induced in rats using the classical method of bilateral ovariectomy and additional calcium and vitamin deficient diet. In addition, wedge-shaped defects of 3, 4, or 5 mm were generated in the distal metaphyseal area of femur via osteotomy. The 4 mm defects were subsequently used for implantation studies where bone substitution materials of calcium phosphate cement, composites of collagen and silica, and iron foams with interconnecting pores were inserted. Different materials were partly additionally functionalized by strontium or bisphosphonate whose positive effects in osteoporosis treatment are well known. The lymphatic vessels were identified by immunohistochemistry using an antibody against podoplanin. Podoplanin immunopositive lymphatic vessels were detected in the granulation tissue filling the fracture gap, surrounding the implant and growing into the iron foam through its interconnected pores. Significant more lymphatic capillaries were counted at the implant interface of composite, strontium and bisphosphonate functionalized iron foam. A significant increase was also observed in the number of lymphatics situated in the pores of strontium coated iron foam. In conclusion, our results indicate the occurrence of lymphatic vessels in osteoporotic bone. Our results show that lymphatic vessels are localized at the implant interface and in the fracture gap where they might be involved in the removal of

  6. Obesity, blood vessels and metabolic syndrome.

    Science.gov (United States)

    Tesauro, M; Cardillo, C

    2011-09-01

    Obesity is rising worldwide at an alarming rate and so is the incidence of obesity-related disorders, such as the metabolic syndrome, type 2 diabetes and cardiovascular diseases. The obesity-dependent vascular damage appears to be derived from a variety of changes in the adipose tissue, leading to a chronic inflammatory state and dysregulation of adipocyte-derived factors. This, in turn, impairs vascular homeostasis by determining an unbalance between the protective effect of the nitric oxide pathway and the unfavourable action of the endothelin-1 system. In addition, hyperinsulinemia and insulin resistance contribute to vascular dysfunction because the opposing endothelium-dependent vasodilating and vasoconstrictor effects of insulin are shifted towards a predominant vasoconstriction in patients with obesity. Importantly, emerging evidence suggests that the vascular dysfunction of obesity is not only limited to the endothelium but also involves the other layers of the vessel wall. In particular, obesity-related changes in vascular smooth muscle seem to disrupt the physiological facilitatory action of insulin on the responsiveness to vasodilator stimuli, whereas the adventitia and the perivascular fat appear to be a source of proinflammatory and vasoactive factors that may contribute to endothelial and smooth muscle cell dysfunction and to the pathogenesis of vascular disease.

  7. Digital data acquisition for a CAD/CAM-fabricated titanium framework and zirconium oxide restorations for an implant-supported fixed complete dental prosthesis.

    Science.gov (United States)

    Lin, Wei-Shao; Metz, Michael J; Pollini, Adrien; Ntounis, Athanasios; Morton, Dean

    2014-12-01

    This dental technique report describes a digital workflow with digital data acquisition at the implant level, computer-aided design and computer-aided manufacturing fabricated, tissue-colored, anodized titanium framework, individually luted zirconium oxide restorations, and autopolymerizing injection-molded acrylic resin to fabricate an implant-supported, metal-ceramic-resin fixed complete dental prosthesis in an edentulous mandible. The 1-step computer-aided design and computer-aided manufacturing fabrication of titanium framework and zirconium oxide restorations can provide a cost-effective alternative to the conventional metal-resin fixed complete dental prosthesis.

  8. Light and electron microscopic observations of blood vessels in neurilemoma.

    Science.gov (United States)

    Kasantikul, V; Glick, A D; Netsky, M G

    1979-12-01

    A study of 105 cases of neurilemoma disclosed frequent alterations of blood vessels, including hyalinized walls. Many vascular walls were formed by tumor cells. Two cases were analyzed by electron microscopy, and showed fenestrae, patent interendothelial gap junctions, and leakage of RBCs. The presence of erythrocytes in the gap junction and outside vessels is a factor acounting for xanthochromia of the CSF, and serum leakage for the frequent increase in CSF protein in cases of neurilemoma. Attenuation of endothelial cells increases the liability of vessels to bleed within the tumor. Massive bleeding may cause subarachnoid hemorrhage on rare occasions. Hyalinized vessels and dense collagen are features contributing to the relative infrequence of major hemorrhage. Evidence is presented that Schwann and perineural cells are similar.

  9. Transition from failing dentition to full-arch fixed implant-supported prosthesis with a staged approach using removable partial dentures: a case series.

    Science.gov (United States)

    Cortes, Arthur Rodriguez Gonzalez; Cortes, Djalma Nogueira; No-Cortes, Juliana; Arita, Emiko Saito

    2014-06-01

    The present retrospective case series is aimed at evaluating a staged approach using a removable partial denture (RPD) as an interim prosthesis in treatment to correct a failing dentition until such time as a full-arch fixed implant-supported prosthesis may be inserted. Eight patients, who had undergone maxillary full-arch rehabilitation with dental implants due to poor prognosis of their dentitions, were analyzed. All treatment included initial periodontal therapy and a strategic order of extraction of hopeless teeth. An RPD supported by selected teeth rehabilitated the compromised arch during implant osseointegration. These remaining teeth were extracted prior to definitive prosthesis delivery. Advantages and drawbacks of this technique were also recorded for the cases presented. Among the advantages provided by the staged approach are simplicity of fabrication, low cost, and ease of insertion. Additionally, RPD tooth support prevented contact between the interim prosthesis and healing abutments, promoting implant osseointegration. The main drawbacks were interference with speech and limited esthetic results. Implant survival rate was 100% within a follow-up of at least 1 year. The use of RPDs as interim prostheses allowed for the accomplishment of the analyzed rehabilitation treatments. It is a simple treatment alternative for patients with a low smile line.

  10. Aminopeptidase A is a functional target in angiogenic blood vessels.

    NARCIS (Netherlands)

    Marchio, S.; Lahdenranta, J.; Schlingemann, R.O.; Valdembri, D.; Wesseling, P.; Arap, M.A.; Hajitou, A.; Ozawa, M.G.; Trepel, M.; Giordano, R.J.; Nanus, D.M.; Dijkman, H.B.P.M.; Oosterwijk, E.; Sidman, R.L.; Cooper, M.D.; Bussolino, F.; Pasqualini, R.; Arap, W.

    2004-01-01

    We show that a membrane-associated protease, aminopeptidase A (APA), is upregulated and enzymatically active in blood vessels of human tumors. To gain mechanistic insight, we evaluated angiogenesis in APA null mice. We found that, although these mice develop normally, they fail to mount the expected

  11. H2S and Blood Vessels: An Overview.

    Science.gov (United States)

    Yang, Guangdong; Wang, Rui

    2015-01-01

    The physiological and biomedical importance of hydrogen sulfide (H2S) has been fully recognized in the cardiovascular system as well as in the rest of the body. In blood vessels, cystathionine γ-lyase (CSE) is a major H2S-producing enzyme expressed in both smooth muscle and endothelium as well as periadventitial adipose tissues. Regulation of H2S production from CSE is controlled by a complex integration of transcriptional, posttranscriptional, and posttranslational mechanisms in blood vessels. In smooth muscle cells, H2S regulates cell apoptosis, phenotypic switch, relaxation and contraction, and calcification. In endothelial cells, H2S controls cell proliferation, cellular senescence, oxidative stress, inflammation, etc. H2S interacts with nitric oxide and acts as an endothelium-derived relaxing factor and an endothelium-derived hyperpolarizing factor. H2S generated from periadventitial adipose tissues acts as an adipocyte-derived relaxing factor and modulates the vascular tone. Extensive evidence has demonstrated the beneficial roles of the CSE/H2S system in various blood vessel diseases, such as hypertension, atherosclerosis, and aortic aneurysm. The important roles signaling in the cardiovascular system merit further intensive and extensive investigation. H2S-releasing agents and CSE activators will find their great applications in the prevention and treatment of blood vessel-related disorders.

  12. Fractal structures in stenoses and aneurysms in blood vessels.

    Science.gov (United States)

    Schelin, Adriane B; Károlyi, György; de Moura, Alessandro P S; Booth, Nuala A; Grebogi, Celso

    2010-12-28

    Recent advances in the field of chaotic advection provide the impetus to revisit the dynamics of particles transported by blood flow in the presence of vessel wall irregularities. The irregularity, being either a narrowing or expansion of the vessel, mimicking stenoses or aneurysms, generates abnormal flow patterns that lead to a peculiar filamentary distribution of advected particles, which, in the blood, would include platelets. Using a simple model, we show how the filamentary distribution depends on the size of the vessel wall irregularity, and how it varies under resting or exercise conditions. The particles transported by blood flow that spend a long time around a disturbance either stick to the vessel wall or reside on fractal filaments. We show that the faster flow associated with exercise creates widespread filaments where particles can get trapped for a longer time, thus allowing for the possible activation of such particles. We argue, based on previous results in the field of active processes in flows, that the non-trivial long-time distribution of transported particles has the potential to have major effects on biochemical processes occurring in blood flow, including the activation and deposition of platelets. One aspect of the generality of our approach is that it also applies to other relevant biological processes, an example being the coexistence of plankton species investigated previously.

  13. Penile prosthesis implantation and tunica albuginea incision without grafting in the treatment of Peyronie's disease with erectile dysfunction.

    Science.gov (United States)

    Djordjevic, Miroslav L; Kojovic, Vladimir

    2013-05-01

    We evaluated penile prosthesis implantation with tunica albuginea-relaxing incisions without grafting in the treatment of Peyronie's disease associated with erectile dysfunction. Between April 2005 and June 2011, 62 patients underwent surgery due to severe Peyronie's disease associated with erectile dysfunction. Malleable and inflatable penile prostheses were inserted in 49 and 13 cases, respectively. Penile prostheses were inserted into the corpora cavernosa using the standard ventral approach. After lifting the neurovascular bundle, the tunica albuginea was incised and opened at the plaque region to correct the deformities and to lengthen the penis. Subsequently, the wide neurovascular bundle was replaced, and all incisions of the tunica albuginea were covered to prevent corporal grafting. In the median follow-up of 35 months (range 14-82 months), the penis was completely straightened in 59 (95%) patients. Numbness of the glans, which the patients found initially upsetting, decreased or disappeared spontaneously 3-6 months later. Penile prosthesis implantation with tunica albuginea incisions is a viable alternative in the treatment of Peyronie's disease because the extensive dissection of the neurovascular bundle allows a good approach to the plaque and provides excellent covering of the incised tunica albuginea without additional grafting.

  14. Penile prosthesis implantation and tunica albuginea incision without grafting in the treatment of Peyronie's disease with erectile dysfunction

    Institute of Scientific and Technical Information of China (English)

    Miroslav L Djordjevic; Vladimir Kojovic

    2013-01-01

    We evaluated penile prosthesis implantation with tunica albuginea-relaxing incisions without grafting in the treatment of Peyronie's disease associated with erectile dysfunction.Between April 2005 and June 2011,62 patients underwent surgery due to severe Peyronie's disease associated with erectile dysfunction.Malleable and inflatable penile prostheses ware inserted in 49 and 13 cases,respectively.Penile prostheses were inserted into the corpora cavemosa using the standard ventral approach.After lifting the neurevascular bundle,the tunica albuginea was incised and opened at the plaque region to correct the deformities and to lengthen the penis.Subsequently,the wide neurovascular bundle was replaced,and all incisions of the tunica albuginea were covered to prevent corporal grafting.In the median follow-up of 35 months (range 14-82 months),the penis was completely straightened in 59 (95%) patients.Numbness of the glans,which the patients found initially upsetting,decreased or disappeared spontaneously 3-6 months later.Penile prosthesis implantation with tunica albuginea incisions is a viable alternative in the treatment of Peyronie's disease because the extensive dissection of the neurovascular bundle allows a good approach to the plaque and provides excellent covering of the incised tunica albuginea witheut additional grafting.

  15. Gene expression analysis in human breast cancer associated blood vessels.

    Directory of Open Access Journals (Sweden)

    Dylan T Jones

    Full Text Available Angiogenesis is essential for solid tumour growth, whilst the molecular profiles of tumour blood vessels have been reported to be different between cancer types. Although presently available anti-angiogenic strategies are providing some promise for the treatment of some cancers it is perhaps not surprisingly that, none of the anti-angiogenic agents available work on all tumours. Thus, the discovery of novel anti-angiogenic targets, relevant to individual cancer types, is required. Using Affymetrix microarray analysis of laser-captured, CD31-positive blood vessels we have identified 63 genes that are upregulated significantly (5-72 fold in angiogenic blood vessels associated with human invasive ductal carcinoma (IDC of the breast as compared with blood vessels in normal human breast. We tested the angiogenic capacity of a subset of these genes. Genes were selected based on either their known cellular functions, their enriched expression in endothelial cells and/or their sensitivity to anti-VEGF treatment; all features implicating their involvement in angiogenesis. For example, RRM2, a ribonucleotide reductase involved in DNA synthesis, was upregulated 32-fold in IDC-associated blood vessels; ATF1, a nuclear activating transcription factor involved in cellular growth and survival was upregulated 23-fold in IDC-associated blood vessels and HEX-B, a hexosaminidase involved in the breakdown of GM2 gangliosides, was upregulated 8-fold in IDC-associated blood vessels. Furthermore, in silico analysis confirmed that AFT1 and HEX-B also were enriched in endothelial cells when compared with non-endothelial cells. None of these genes have been reported previously to be involved in neovascularisation. However, our data establish that siRNA depletion of Rrm2, Atf1 or Hex-B had significant anti-angiogenic effects in VEGF-stimulated ex vivo mouse aortic ring assays. Overall, our results provide proof-of-principle that our approach can identify a cohort of

  16. CT-angiography-based evaluation of the aortic annulus for prosthesis sizing in transcatheter aortic valve implantation (TAVI-predictive value and optimal thresholds for major anatomic parameters.

    Directory of Open Access Journals (Sweden)

    Florian Schwarz

    Full Text Available BACKGROUND/OBJECTIVES: To evaluate the predictive value of CT-derived measurements of the aortic annulus for prosthesis sizing in transcatheter aortic valve implantation (TAVI and to calculate optimal cutoff values for the selection of various prosthesis sizes. METHODS: The local IRB waived approval for this single-center retrospective analysis. Of 441 consecutive TAVI-patients, 90 were excluded (death within 30 days: 13; more than mild aortic regurgitation: 10; other reasons: 67. In the remaining 351 patients, the CoreValve (Medtronic and the Edwards Sapien XT valve (Edwards Lifesciences were implanted in 235 and 116 patients. Optimal prosthesis size was determined during TAVI by inflation of a balloon catheter at the aortic annulus. All patients had undergone CT-angiography of the heart or body trunk prior to TAVI. Using these datasets, the diameter of the long and short axis as well as the circumference and the area of the aortic annulus were measured. Multi-Class Receiver-Operator-Curve analyses were used to determine the predictive value of all variables and to define optimal cutoff-values. RESULTS: Differences between patients who underwent implantation of the small, medium or large prosthesis were significant for all except the large vs. medium CoreValve (all p's<0.05. Furthermore, mean diameter, annulus area and circumference had equally high predictive value for prosthesis size for both manufacturers (multi-class AUC's: 0.80, 0.88, 0.91, 0.88, 0.88, 0.89. Using the calculated optimal cutoff-values, prosthesis size is predicted correctly in 85% of cases. CONCLUSION: CT-based aortic root measurements permit excellent prediction of the prosthesis size considered optimal during TAVI.

  17. Micro-PIV measurements of blood flow in extraembryonic blood vessels of chicken embryos.

    Science.gov (United States)

    Lee, Jung Yeop; Ji, Ho Seong; Lee, Sang Joon

    2007-10-01

    The hemodynamic characteristics of blood flow are important in the diagnosis of circulatory diseases, since such diseases are related to wall shear stress of cardiovascular vessels. In chicken embryos at early stages of development, it is possible to directly visualize blood flow inside blood vessels. We therefore employed a micro-PIV technique to assess blood flow in extraembryonic venous and arterial blood vessels of chicken embryos, using red blood cells (RBCs) as tracers and obtaining flow images of RBCs using a high-speed CMOS camera. The mean velocity field showed non-Newtonian flow characteristics. The blood flow in two venous vessels merged smoothly into the Y-shaped downstream vein without any flow separation or secondary flow. Vorticity was high in the inner regions, where the radius of curvature varied greatly. A periodic variation of temporally resolved velocity signals, due to beating of the heart, was observed in arterial blood vessels. The pulsating frequency was obtained by fast Fourier transform analysis using the measured velocity data. The measurement technique used here was useful in analyzing the hemodynamic characteristics of in vivo blood flow in chicken embryos.

  18. Penile prosthesis implant with bi-triangular excision and graft for surgical therapy of Peyronie’s disease: A case report

    Directory of Open Access Journals (Sweden)

    Alexandre de Freitas Miranda

    2016-01-01

    Full Text Available We present a case of a 65-year-old man, who presented with moderate erectile dysfunction and a dorsal penile deviation of 60° caused by Peyronie’s disease. The patient underwent bi-triangularshaped plaque excision, followed by grafting and implantation of inflatable penile prosthesis. Complete penile straightening, without mechanical or geometric abnormalities, was achieved using bi-triangular excision and grafting. Postoperatively, the patient reported high satisfaction with the results and could perform sexual intercourse naturally. This novel technique corrects any degree of penile curvature, permits malleable and semi-rigid penile prosthesis implantation, avoids penile length loss, and eliminates additional incisions. To our knowledge, this case is the first in the literature in which the bi-triangular technique was successfully used for penile prosthesis implantation secondary to Peyronie’s disease. This new technique appears to be a good solution to correct penile curvature during penile prosthesis implantation for the treatment of Peyronie’s disease associated with erectile dysfunction.

  19. Replacement of missing anterior tooth using screw retained implant prosthesis in the esthetic zone: a case report with 3 years of follow up.

    Science.gov (United States)

    Ahmad, Manawar; Dhanasekar, B; Aparna, I N; Naim, Hina

    2014-09-01

    As more and more dental practitioners are focusing on implant-supported fixed restorations, some clinicians favor the use of cement retained restorations while others consider screw-retained prosthesis to be the best choice. As both types of prostheses have certain advantages and disadvantages, clinicians should be aware of the limitations of each type. Screw-retained implant restorations have an advantage of predictable retention, retrievability and lack of potentially retained sub-gingival cement. However, a few disadvantages exist such as precise placement of the implant for optimal and esthetic location of the screw access hole and obtaining passive fit. On the other hand, cement retained restorations eliminates unaesthetic screw access holes; have passive fit of castings; reduce stress to splinted implants because of minor misfit of the framework; reduced complexity of lab procedures; enhanced esthetics; reduced cost factors and non disrupted morphology of the occlusal table. This case report presents the replacement of missing left central incisor using screw-retained implant prosthesis due to palatal trajectory of the implant placement and inadequate abutment height for retention of cement retained prosthesis.

  20. Full mouth rehabilitation of a patient with mandibular implant screw retained Fp-3 prosthesis opposing maxillary acrylic removable over-denture.

    Science.gov (United States)

    Jain, Ashish R; Nallaswamy, Deepak; Ariga, Padma; Philip, Jacob Mathew

    2013-04-01

    A hybrid denture is one that is fabricated over a metal framework and retained by screws threaded into the implant abutments. The anterior part of a mandibular hybrid denture is fixed on implants while the posterior part of the denture is extended and cantilevered from implants. This article presents the fabrication of a maxillary over-denture opposing mandibular implant retained hybrid prosthesis. A total of four implants were placed in the mandibular arch. Castable abutments were used to produce the optimal angulations. Framework was waxed, cast recovered, and the fit was refined until the framework seated passively on the master cast. The mandibular denture teeth were waxed to the hybrid framework, and a final wax try-in was performed to verify and correct maxillomandibular relations before processing. The prosthesis was inserted after verification of occlusion, retention, and stability. The rehabilitation of edentulous patients with hybrid dentures has been observed to achieve greater masticatory function and psychological satisfaction than with conventional over-dentures. Producing a passive-fitting substructure for a fixed removable screw retained hybrid prosthesis is arguably one of the most technically complex tasks in implant dentistry. The technique presented may not initially produce a perfectly passive framework, but use of disclosing media and adjusting the internal aspect of the casting can result in non-binding, fully seated prostheses.

  1. Full mouth rehabilitation of a patient with mandibular implant screw retained Fp-3 prosthesis opposing maxillary acrylic removable over-denture

    Directory of Open Access Journals (Sweden)

    Ashish R Jain

    2013-01-01

    Full Text Available A hybrid denture is one that is fabricated over a metal framework and retained by screws threaded into the implant abutments. The anterior part of a mandibular hybrid denture is fixed on implants while the posterior part of the denture is extended and cantilevered from implants. This article presents the fabrication of a maxillary over-denture opposing mandibular implant retained hybrid prosthesis. A total of four implants were placed in the mandibular arch. Castable abutments were used to produce the optimal angulations. Framework was waxed, cast recovered, and the fit was refined until the framework seated passively on the master cast. The mandibular denture teeth were waxed to the hybrid framework, and a final wax try-in was performed to verify and correct maxillomandibular relations before processing. The prosthesis was inserted after verification of occlusion, retention, and stability. The rehabilitation of edentulous patients with hybrid dentures has been observed to achieve greater masticatory function and psychological satisfaction than with conventional over-dentures. Producing a passive-fitting substructure for a fixed removable screw retained hybrid prosthesis is arguably one of the most technically complex tasks in implant dentistry. The technique presented may not initially produce a perfectly passive framework, but use of disclosing media and adjusting the internal aspect of the casting can result in non-binding, fully seated prostheses.

  2. By Different Cellular Mechanisms, Lymphatic Vessels Sprout by Endothelial Cell Recruitment Whereas Blood Vessels Grow by Vascular Expansion

    Science.gov (United States)

    Parsons-Wingerter, Patricia; McKay, Terri L.; Leontiev, Dmitry; Condrich, Terence K.; DiCorleto, Paul E.

    2005-01-01

    The development of effective vascular therapies requires the understanding of all modes of vessel formation contributing to vasculogenesis, angiogenesis (here termed hemangiogenesis) and lymphangiogenesis. We show that lymphangiogenesis proceeds by blind-ended vessel sprouting via recruitment of isolated endothelial progenitor cells to the tips of growing vessels, whereas hemangiogenesis occurs by non-sprouting vessel expansion from the capillary network, during middevelopment in the quail chorioallantoic membrane (CAM). Blood vessels expanded out of capillaries that displayed transient expression of alpha smooth muscle actin (alphaSMA), accompanied by mural recruitment of migratory progenitor cells expressing SMA. Lymphatics and blood vessels were identified by confocal/fluorescence microscopy of vascular endothelial growth factor (VEGF) receptors VEGFR-1 and VEGFR-2, alphaSMA (expressed on CAM blood vessels but not on lymphatics), homeobox transcription factor Prox-1 (specific to CAM lymphatic endothelium), and the quail hematopoetic/vascular marker, QH-1. Expression of VEGFR-1 was highly restricted to blood vessels (primarily capillaries). VEGFR-2 was expressed intensely in isolated hematopoietic cells, lymphatic vessels and moderately in blood vessels. Prox-1 was absent from endothelial progenitor cells prior to lymphatic recruitment. Although vascular endothelial growth factor-165 (VEGF(sub 165)) is a key regulator of numerous cellular processes in hemangiogenesis and vasculogenesis, the role of VEGF(sub 165) in lymphangiogenesis is less clear. Exogenous VEGF(sub 165) increased blood vessel density without changing endogenous modes of vascular/lymphatic vessel formation or marker expression patterns. However, VEGF(sub 165) did increase the frequency of blood vascular anastomoses and strongly induced the antimaturational dissociation of lymphatics from blood vessels, with frequent formation of homogeneous lymphatic networks.

  3. Lattice Boltzmann Simulation of Blood Flow in Blood Vessels with the Rolling Massage

    Institute of Scientific and Technical Information of China (English)

    YI Hou-Hui; XU Shi-Xiong; QIAN Yue-Hong; FANG Hai-Ping

    2005-01-01

    @@ The rolling massage manipulation is a classic Chinese massage, which is expected to improve the circulation by pushing, pulling and kneading of the muscle. A model for the rolling massage manipulation is proposed and the lattice Boltzmann method is applied to study the blood flow in the blood vessels. The simulation results show that the blood flux is considerably modified by the rolling massage and the explicit value depends on the rolling frequency, the rolling depth, and the diameter of the vessel. The smaller the diameter of the blood vessel, the larger the enhancement of the blood flux by the rolling massage. The model, together with the simulation results,is expected to be helpful to understand the mechanism and further development of rolling massage techniques.

  4. Investigation on artificial blood vessels prepared from bacterial cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Zang, Shanshan; Zhang, Ran; Chen, Hua; Lu, Yudong; Zhou, Jianhai [Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China); Chang, Xiao; Qiu, Guixing; Wu, Zhihong [Department of Orthopaedics, Peking Union Medical College Hospital, Beijing 100730 (China); Yang, Guang, E-mail: yang_sunny@yahoo.com [Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2015-01-01

    BC (bacterial cellulose) exhibits quite distinctive properties than plant cellulose. The outstanding properties make BC a promising material for preparation of artificial blood vessel. By taking advantage of the high oxygen permeability of PDMS (polydimethylsiloxane) as a tubular template material, a series of BC tubes with a length of 100 mm, a thickness of 1 mm and an outer diameter of 4 or 6 mm were biosynthesized with the help of Gluconacetobacter xylinum. Through characterization by SEM (scanning electron microscope), tensile testing and thermal analysis, it is demonstrated that BC tubes are good enough for artificial blood vessel with elaborated nano-fiber architecture, qualified mechanical properties and high thermal stability. In addition, measurement of biocompatibility also shows that BC tubes are greatly adaptable to the in vivo environment. The results indicate that BC tubes have great potential for being utilized as tubular scaffold materials in the field of tissue engineering. - Highlights: • Bacterial cellulose (BC) can be made into tubular shape through PDMS mold. • BC represents a fine nanofiber network. • The mechanical and thermal properties of BC mimic the situation of real vessel. • BC exhibits attractive biocompatible properties as a substitution of vessel.

  5. Investigation on artificial blood vessels prepared from bacterial cellulose.

    Science.gov (United States)

    Zang, Shanshan; Zhang, Ran; Chen, Hua; Lu, Yudong; Zhou, Jianhai; Chang, Xiao; Qiu, Guixing; Wu, Zhihong; Yang, Guang

    2015-01-01

    BC (bacterial cellulose) exhibits quite distinctive properties than plant cellulose. The outstanding properties make BC a promising material for preparation of artificial blood vessel. By taking advantage of the high oxygen permeability of PDMS (polydimethylsiloxane) as a tubular template material, a series of BC tubes with a length of 100 mm, a thickness of 1mm and an outer diameter of 4 or 6mm were biosynthesized with the help of Gluconacetobacter xylinum. Through characterization by SEM (scanning electron microscope), tensile testing and thermal analysis, it is demonstrated that BC tubes are good enough for artificial blood vessel with elaborated nano-fiber architecture, qualified mechanical properties and high thermal stability. In addition, measurement of biocompatibility also shows that BC tubes are greatly adaptable to the in vivo environment. The results indicate that BC tubes have great potential for being utilized as tubular scaffold materials in the field of tissue engineering.

  6. Blood vessels restrain pancreas branching, differentiation and growth.

    Science.gov (United States)

    Magenheim, Judith; Ilovich, Ohad; Lazarus, Alon; Klochendler, Agnes; Ziv, Oren; Werman, Roni; Hija, Ayat; Cleaver, Ondine; Mishani, Eyal; Keshet, Eli; Dor, Yuval

    2011-11-01

    How organ size and form are controlled during development is a major question in biology. Blood vessels have been shown to be essential for early development of the liver and pancreas, and are fundamental to normal and pathological tissue growth. Here, we report that, surprisingly, non-nutritional signals from blood vessels act to restrain pancreas growth. Elimination of endothelial cells increases the size of embryonic pancreatic buds. Conversely, VEGF-induced hypervascularization decreases pancreas size. The growth phenotype results from vascular restriction of pancreatic tip cell formation, lateral branching and differentiation of the pancreatic epithelium into endocrine and acinar cells. The effects are seen both in vivo and ex vivo, indicating a perfusion-independent mechanism. Thus, the vasculature controls pancreas morphogenesis and growth by reducing branching and differentiation of primitive epithelial cells.

  7. Photoacoustic monitoring and imaging of blood vessels in tissue

    Science.gov (United States)

    Kolkman, Roy G. M.; Pilatou, Magdalena C.; Steenbergen, Wiendelt; de Mul, Frits F. M.

    2002-06-01

    Using very sensitive photoacoustical detectors we localized and monitored the blood content in tissue. In these detectors a PVdF-layer has been used as piezo-electric material and also fibers for the illumination of the sample are integrated. The resolution is about 20micrometers in depth and about 50-100micrometers laterally. The wavelengths of the laser light were 532 and 1064 nm. With these colors we can measure at different depths in tissue. The measurements concerned blood perfusion in real tissue: vessels in chicken breast, in test animals at various positions and in the human arm.

  8. Outcome of penile prosthesis implantation: are malleable prostheses an appropriate treatment option in patients with erectile dysfunction caused by prior radical surgery?

    Science.gov (United States)

    Sevinc, Cuneyd; Ozkaptan, Orkunt; Balaban, Muhsin; Yucetas, Ugur; Karadeniz, Tahir

    2016-04-26

    The aim of our study was to evaluate the outcome of penile prosthesis implantation in patients with various comorbidities as a cause of erectile dysfunction (ED). The data of 181 patients who underwent surgery between 1998 and 2012 in two centers were evaluated. The mean age of the patients was 52.2 years (range: 31-71 years). The study group contained 162 patients (89.5%) with malleable prostheses and 19 (10.5%) with inflatable implants. All patients were re-evaluated 1 month later to assess prosthesis function and complications, and further re-examinations were performed if needed. Satisfaction was defined as having satisfactory intercourse and happiness with the device in general. The follow-up period was at least 12 months for each patient. The postoperative complication rate was 32% (n = 58). The number of complications with inflatable and malleable prostheses was 7 (3.9%) and 51 (28.1%), respectively. Overall, 21 prostheses (11.6%) had to be removed because of various complications and patient dissatisfaction. Patients with prior radical surgery had higher extraction rates (ƛ = 14.606, P prosthesis, while 21 (11.6%) were unsatisfied. The high explantation rate in patients with prior surgery was remarkable in our study. Our results revealed that a malleable prosthesis should not be the preferred type of implant for patients with prior surgery.

  9. Over-expression of Slit2 induces vessel formation and changes blood vessel permeability in mouse brain

    Institute of Scientific and Technical Information of China (English)

    Hai-xiong HAN; Jian-guo GENG

    2011-01-01

    Aim:To investigate the effect of the axon guidance cue Slit2 on the density of blood vessels and permeability of the blood-brain barrier in mouse brain.Methods:hSlit2 transgenic mouse line was constructed,and the phenotypes of the mice were compared with wild-type mice in respect to the lateral ventricle (LV),ventricle pressure,and the choroids plexus.An in vivo Miles permeability assay and an amyloid-β permeability assay were used to assess the permeability of brain blood vessels.Brain vessel casting and intracerebral hemorrhage models were built to investigate vessel density in the transgenic mice.An in vitro permeability assay was used to test whether Slit2 could change the permeability and tight junctions of blood vessel endothelial cells.Results:Hydrocephalus occurred in some transgenic mice,and a significantly larger lateral ventricle area and significantly higher ventricle pressure were observed in the transgenic mice.The transgenic mice displayed changed construction of the choroids plexus,which had more micro vessels,dilated vessels,gaps between epithelial cells and endothelial cells than wild-type mice.Slit2 significantly increased brain vessel density and the permeability of brain vessels to large molecules.These blood vessels were more sensitive to cues that induce brain hemorrhage.At the cellular level,Slit2 disturbed the integrity of tight junctions in blood vessel endothelial cells and improved the permeability of the endothelial cell layer.Thus,it promoted the entry of amyloid-β peptides from the serum into the central nervous system,where they bound to neurons.Conclusion:Slit2 increases vessel density and permeability in the brains of transgenic mice.Thus,Slit2 induces numerous changes in brain vessels and the barrier system.

  10. Noncontact discrimination of animal and human blood with vacuum blood vessel and factors affect the discrimination

    Science.gov (United States)

    Zhang, Linna; Zhang, Shengzhao; Sun, Meixiu; Li, Hongxiao; Li, Yingxin; Fu, Zhigang; Guan, Yang; Li, Gang; Lin, Ling

    2017-03-01

    Discrimination of human and nonhuman blood is crucial for import-export ports and inspection and quarantine departments. Current methods are usually destructive, complicated and time-consuming. We had previously demonstrated that visible diffuse reflectance spectroscopy combining PLS-DA method can successfully realize human blood discrimination. In that research, the spectra were measured with the fiber probe under the surface of blood samples. However, open sampling may pollute the blood samples. Virulence factors in blood samples can also endanger inspectors. In this paper, we explored the classification effect with the blood samples measured in the original containers-vacuum blood vessel. Furthermore, we studied the impact of different conditions of blood samples, such as coagulation and hemolysis, on the prediction ability of the discrimination model. The calibration model built with blood samples in different conditions displayed a satisfactory prediction result. This research demonstrated that visible and near-infrared diffuse reflectance spectroscopy method was potential for noncontact discrimination of human blood.

  11. Blood vessel classification into arteries and veins in retinal images

    Science.gov (United States)

    Kondermann, Claudia; Kondermann, Daniel; Yan, Michelle

    2007-03-01

    The prevalence of diabetes is expected to increase dramatically in coming years; already today it accounts for a major proportion of the health care budget in many countries. Diabetic Retinopathy (DR), a micro vascular complication very often seen in diabetes patients, is the most common cause of visual loss in working age population of developed countries today. Since the possibility of slowing or even stopping the progress of this disease depends on the early detection of DR, an automatic analysis of fundus images would be of great help to the ophthalmologist due to the small size of the symptoms and the large number of patients. An important symptom for DR are abnormally wide veins leading to an unusually low ratio of the average diameter of arteries to veins (AVR). There are also other diseases like high blood pressure or diseases of the pancreas with one symptom being an abnormal AVR value. To determine it, a classification of vessels as arteries or veins is indispensable. As to our knowledge despite the importance there have only been two approaches to vessel classification yet. Therefore we propose an improved method. We compare two feature extraction methods and two classification methods based on support vector machines and neural networks. Given a hand-segmentation of vessels our approach achieves 95.32% correctly classified vessel pixels. This value decreases by 10% on average, if the result of a segmentation algorithm is used as basis for the classification.

  12. Modeling Of Blood Vessel Constriction In 2-D Case Using Molecular Dynamics Method

    CERN Document Server

    Rendi, Mohamad; Viridi, Sparisoma

    2013-01-01

    Blood vessel constriction is simulated with particle-based method using a molecular dynamics authoring software known as Molecular Workbench (WM). Blood flow and vessel wall, the only components considered in constructing a blood vessel, are all represented in particle form with interaction potentials: Lennard-Jones potential, push-pull spring potential, and bending spring potential. Influence of medium or blood plasma is accommodated in plasma viscosity through Stokes drag force. It has been observed that pressure p is increased as constriction c is increased. Leakage of blood vessel starts at 80 % constriction, which shows existence of maximum pressure that can be overcome by vessel wall.

  13. Osteomyelitis of sternum and rib after breast prosthesis implantation: A rare or underestimated infection?

    Science.gov (United States)

    Seng, Piseth; Alliez, Antoine; Honnorat, Estelle; Menard, Amelie; Casanova, Dominique; Stein, Andreas

    2014-01-01

    Sternum and rib osteomyelitis complicated from breast implant infection is rare. We report a case of early sternum and rib osteomyelitis occurred during breast implant infection managed in an inter-regional referral center for bone/joint infections in the south of France. PMID:26793446

  14. Osteomyelitis of sternum and rib after breast prosthesis implantation: A rare or underestimated infection?

    Directory of Open Access Journals (Sweden)

    Piseth Seng

    2015-01-01

    Full Text Available Sternum and rib osteomyelitis complicated from breast implant infection is rare. We report a case of early sternum and rib osteomyelitis occurred during breast implant infection managed in an inter-regional referral center for bone/joint infections in the south of France.

  15. Angiogenesis and blood vessel stability in inflammatory arthritis.

    LENUS (Irish Health Repository)

    Kennedy, Aisling

    2012-02-01

    OBJECTIVE: To assess blood vessel stability in inflammatory synovial tissue (ST) and to examine neural cell adhesion molecule (NCAM), oxidative DNA damage, and hypoxia in vivo. METHODS: Macroscopic vascularity and ST oxygen levels were determined in vivo in patients with inflammatory arthritis who were undergoing arthroscopy. Vessel maturity\\/stability was quantified in matched ST samples by dual immunofluorescence staining for factor VIII (FVIII)\\/alpha-smooth muscle actin (alpha-SMA). NCAM and 8-oxo-7,8-dihydro-2\\'-deoxyguanosine (8-oxodG) were examined by immunohistochemistry. Angiogenesis was assessed in vitro, using human dermal endothelial cells (HDECs) in a Matrigel tube formation assay. RESULTS: A significant number of immature vessels (showing no pericyte recruitment) was observed in tissue from patients with inflammatory arthritis (P < 0.001), in contrast to osteoarthritic and normal tissue, which showed complete recruitment of pericytes. Low in vivo PO(2) levels in the inflamed joint (median [range] 22.8 [3.2-54.1] mm Hg) were inversely related to increased macroscopic vascularity (P < 0.04) and increased microscopic expression of FVIII and alpha-SMA (P < 0.04 and P < 0.03, respectively). A significant proportion of vessels showed focal expression of NCAM and strong nuclear 8-oxodG expression, implicating a loss of EC-pericyte contact and increased DNA damage, levels of which were inversely associated with low in vivo PO(2) (P = 0.04 for each comparison). Circulating cells were completely negative for 8-oxodG. Exposure of HDEC to 3% O(2) (reflecting mean ST in vivo measurements) significantly increased EC tube formation (P < 0.05). CONCLUSION: Our findings indicate the presence of unstable vessels in inflamed joints associated with hypoxia, incomplete EC-pericyte interactions, and increased DNA damage. These changes may further contribute to persistent hypoxia in the inflamed joint to further drive this unstable microenvironment.

  16. FEM evaluation of cemented-retained versus screw-retained dental implant single-tooth crown prosthesis

    Science.gov (United States)

    Cicciu, Marco; Bramanti, Ennio; Matacena, Giada; Guglielmino, Eugenio; Risitano, Giacomo

    2014-01-01

    Prosthetic rehabilitation of partial or total edentulous patients is today a challenge for clinicians and dental practitioners. The application of dental implants in order to recover areas of missing teeth is going to be a predictable technique, however some important points about the implant angulation, the stress distribution over the bone tissue and prosthetic components should be well investigated for having final long term clinical results. Two different system of the prosthesis fixation are commonly used. The screw retained crown and the cemented retained one. All of the two restoration techniques give to the clinicians several advantages and some disadvantages. Aim of this work is to evaluate all the mechanical features of each system, through engineering systems of investigations like FEM and Von Mises analyses. The FEM is today a useful tool for the prediction of stress effect upon material and biomaterial under load or strengths. Specifically three different area has been evaluated through this study: the dental crown with the bone interface; the passant screw connection area; the occlusal surface of the two different type of crown. The elastic features of the materials used in the study have been taken from recent literature data. Results revealed an adequate response for both type of prostheses, although cemented retained one showed better results over the occlusal area. PMID:24955150

  17. FEM evaluation of cemented-retained versus screw-retained dental implant single-tooth crown prosthesis.

    Science.gov (United States)

    Cicciu, Marco; Bramanti, Ennio; Matacena, Giada; Guglielmino, Eugenio; Risitano, Giacomo

    2014-01-01

    Prosthetic rehabilitation of partial or total edentulous patients is today a challenge for clinicians and dental practitioners. The application of dental implants in order to recover areas of missing teeth is going to be a predictable technique, however some important points about the implant angulation, the stress distribution over the bone tissue and prosthetic components should be well investigated for having final long term clinical results. Two different system of the prosthesis fixation are commonly used. The screw retained crown and the cemented retained one. All of the two restoration techniques give to the clinicians several advantages and some disadvantages. Aim of this work is to evaluate all the mechanical features of each system, through engineering systems of investigations like FEM and Von Mises analyses. The FEM is today a useful tool for the prediction of stress effect upon material and biomaterial under load or strengths. Specifically three different area has been evaluated through this study: the dental crown with the bone interface; the passant screw connection area; the occlusal surface of the two different type of crown. The elastic features of the materials used in the study have been taken from recent literature data. Results revealed an adequate response for both type of prostheses, although cemented retained one showed better results over the occlusal area.

  18. Hydroxyapatite ocular prosthesis implants wrapped by human amniotic membrane%羊膜包裹的羟基磷灰石义眼座植入

    Institute of Scientific and Technical Information of China (English)

    刘文斌; 孙思勤; 温耀春; 万川

    2001-01-01

    Objective To observe the clinical effects of human amniotic membrane as an alternative substrate for wrapping hydroxyapatite ocular prosthesis implants.Methods After enucleation, hydroxyapatite orbital implants wrapped by human amniotic membrane were implanted with four rectus sutured to the implants .Among them, 4 cases were given primary implantation and 3 cases secondary implantation.Results After 8 to 39 week follow-up, it was found that in 6 cases, the eyelids were plump and prosthesis moved well, but one implant was removed because of failure of scleral patch graft for implant exposure.Conclusion The clinical results were satisfactory for ocular prosthesis implantation of hydroxyapatite sphere wrapped by human amniotic membrane, which may be considered as an alternative substrate for ocular prosthesis implants wrapper.%目的观察羊膜包裹的羟基磷灰石义眼座植入的临床效果。方法 7例眼球摘除术后,以库存的人羊膜缝合包裹选定的合适直径的义眼座,后段覆盖羊膜多处开窗后将义眼座植入肌椎内,再通过义眼座前1/3处穿出 4条缝线将 4条直肌缝合固定在义眼座上,然后分层缝合筋膜、结膜。结果追踪观察 8~39 wk,除 1例因局部放疗后眼结膜、筋膜萎缩,义眼座暴露,库存异体巩膜修补失败后,将义眼座取出外,其余 6例外观饱满,义眼活动良好。结论羊膜包裹的羟基磷灰石义眼座效果良好。羊膜可成为新的义眼座包裹物。

  19. The effects of the synthetic nocistatin on blood vessel activities

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Nocistatin was synthesized by the solid-phase peptide synthesismethod. Its effects on rat systemic arterial pressure; rat hindquarter vascular bed resistance; tension of rabbit pectoral, abdominal, femoral aorta muscle strips without endothelium; and nociceptin induced decreases of rat systemic arterial pressure were determined. The results showed that nocistatin can increase the systemic arterial pressure, increase the hindquarter vascular bed resistance and induce the contraction significantly of abdominal, femoral aorta muscle strips without endothelium; it has no significant effect on tension of pectoral aorta muscle strips, it cannot antagonize significantly the decrease of rat systemic arterial pressure induced by nociceptin. These results suggest that nocistatin has some important effects on blood vessel activities.

  20. Plasma membrane electron transport in frog blood vessels

    Indian Academy of Sciences (India)

    Rashmi P Rao; K Nalini; J Prakasa Rao

    2009-12-01

    In an attempt to see if frog blood vessels possess a plasma membrane electron transport system, the postcaval vein and aorta isolated from Rana tigrina were tested for their ability to reduce ferricyanide, methylene blue, and 2,6-dichloroindophenol. While the dyes remained unchanged, ferricyanide was reduced to ferrocyanide. This reduction was resistant to inhibition by cyanide and azide. Heptane extraction or formalin fixation of the tissues markedly reduced the capability to reduce ferricyanide. Denuded aortas retained only 30% of the activity of intact tissue. Our results indicate that the amphibian postcaval vein and aorta exhibit plasma membrane electron transport

  1. A review of surgical strategies for penile prosthesis implantation in patients with Peyronie's disease.

    Science.gov (United States)

    Anaissie, James; Yafi, Faysal A

    2016-06-01

    The introduction of the inflatable penile prosthesis (IPP) has revolutionized the treatment of patients with both Peyronie's disease (PD) and erectile dysfunction (ED). A thorough literature review was performed in order to review the surgical strategies used to treat PD, using the PubMed online database with the keywords "penile prosthesis", "surgical management" and "Peyronie's disease". Patient satisfaction rates of 72-100% and partner satisfaction rates of 89% have been reported in the literature, although strong preoperative education may be needed to prepare patients for risks such as penile shortening, seen in up to 54% of patients. Three-piece IPPs are most commonly used, and when comparing the two most popular models (AMS 700 CX vs. Coloplast Titan), no significant differences were seen in functional outcomes or patient satisfaction. Simple insertion of an IPP has been shown to resolve curvature in 33-90% of patients, but surgeons may often need to also utilize ancillary straightening procedures for residual curvatures. Manual modeling can correct residual curvature with an 86-100% success rate, but with a 4% risk of urethral injury. When the post-modeling residual curvature exceeds 30 degrees, a plaque-releasing incision or plication is recommended to further reduce curvature. Grafting is recommended if the resulting incisional defect is larger than two centimeters. Alternative straightening techniques such as plication prior to IPP insertion, endoscopic plaque resection, the "scratch technique" and bone saw plaque incision have also been described.

  2. The importance of psychosexual counselling in the re-establishment of organic and erotic functions after penile prosthesis implantation.

    Science.gov (United States)

    Pisano, F; Falcone, M; Abbona, A; Oderda, M; Soria, F; Peraldo, F; Marson, F; Barale, M; Fiorito, C; Gurioli, A; Frea, B; Gontero, P

    2015-01-01

    Although many studies about penile prosthesis implantation (PPI) have been published so far, only a small amount of them take into account patients and partners outcome in terms of satisfaction and erotic function. The aim of this study is to explore the value of psycosexual counselling in and the sexual and erotic function of penile prosthesis recipients. Thirty patients and their partners were randomised into two groups. In arm A (case group) patients and their partners underwent a multistep psychosexual counselling before and after surgery. In arm B (control group) surgery was performed without the specific psychosexual counselling scheme. Specific questionnaires (International Index of Erectile Function (IIEF) and the Sexual Daydreaming Scale (SDS)) were administered before surgery and 12 months afterwards. Twenty-four months postoperatively patients were asked to complete the Global Assessment Questions (GAQ) and the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS), while their partners were asked to answer to the EDITS partner's section. Between January 2009 and October 2011, we enrolled 30 patients undergoing PPI in our institution (15 in each arm). Twenty-four months postoperative follow-up is available for all of them. No significant differences between the two groups in terms of baseline questionnaires scores were observed. Mean IIEF score was significantly higher in case group (arm A 68.3, arm B 53.4, P-value<0.001). At 12 months after PPI the improvement of erotic function according to SDS was significantly higher in the study group for both patients and their partners. Improvement in satisfaction rates were confirmed at 24 months, with statistically significant scores for EDITS in arm A patients and partners as compared with arm B. PPI with a pre- and postoperative psychosexual counselling scheme resulted in better postoperative sexual activity and erotic function for both patients and partners than PPI alone.

  3. Venous Ligation: A Novel Strategy for Glans Enhancement in Penile Prosthesis Implantation

    OpenAIRE

    Geng-Long Hsu; Hill, James W.; Cheng-Hsing Hsieh; Shih-Ping Liu; Chih-Yuan Hsu

    2014-01-01

    Although penile implantation remains a final solution for patients with refractory impotence, undesirable postoperative effects, including penile size reduction and cold sensation of the glans penis, remain problematic. We report results of a surgical method designed to avoid these problems. From 2003 to 2013, 35 consecutive patients received a malleable penile implant. Of these, 15 men (the enhancing group) were also treated with venous ligation of the retrocoronal venous plexus, deep dorsal...

  4. Photoelastic Stress Analysis Surrounding Implant-Supported Prosthesis and Alveolar Ridge on Mandibular Overdentures

    Directory of Open Access Journals (Sweden)

    Dorival Pedroso da Silva

    2010-01-01

    Full Text Available The purpose of this research was to evaluate the maximum stress around osseointegrated implants and alveolar ridge, in a mandible with left partial resection through a photoelastic mandibular model. The first group consisted of two implants: traditional model (T, implants placed in the position of both canines; fulcrum model (F, implants placed in the position of left canine CL and right lateral incisor LiR. Both models linked through a bar and clips. The second group was consisted of three implants, with implants placed in the position of both canines (CR and CL and the right lateral incisor (LiR, which composed four groups: (1 model with 3 “O” rings, (2 model 2 ERAs, bar with clips, (3 model 2 ERAs bar without clips; (4 model “O” ring bar and ERA. An axial and an oblique load of 6.8 kgf was applied on a overdenture at the 1st Pm, 2nd Pm, and 1st M. Results showed that the area around the left canine (CL was practically free of stress; the left lateral incisor (LiL developed only small tensions, and low stress in all the other cases; the right canine tooth suffered the largest concentrations of stress, mainly with the ERA retention mechanism.

  5. Microfluidic strategy to investigate dynamics of small blood vessel function

    Science.gov (United States)

    Yasotharan, Sanjesh; Bolz, Steffen-Sebastian; Guenther, Axel

    2010-11-01

    Resistance arteries (RAs, 30-300 microns in diameter) that are located within the terminal part of the vascular tree regulate the laminar perfusion of tissue with blood, via the peripheral vascular resistance, and hence controls the systemic blood pressure. The structure of RAs is adapted to actively controlling flow resistance by dynamically changing their diameter, which is non-linearly dependent on the temporal variation of the transmural pressure, perfusion flow rate and spatiotemporal changes in the chemical environment. Increases in systemic blood pressure (hypertension) resulting from pathologic changes in the RA response represent the primary risk factor for cardiovascular diseases. We use a microfluidic strategy to investigate small blood vessels by quantifying structural variations within the arterial wall, RA outer contour and diameter over time. First, we document the artery response to vasomotor drugs that were homogeneously applied at step-wise increasing concentration. Second, we investigate the response in the presence of well-defined axial and circumferential heterogeneities. Artery per- and superfusion is discussed based on microscale PIV measurements of the fluid velocity on both sides of the arterial wall. Structural changes in the arterial wall are quantified using cross-correlation and proper orthogonal decomposition analyses of bright-field micrographs.

  6. An analysis of observer‐rated functional vision in patients implanted with the Argus II Retinal Prosthesis System at three years

    Science.gov (United States)

    Richards, Thomas P; Arditi, Aries; da Cruz, Lyndon; Dagnelie, Gislin; Dorn, Jessy D; Duncan, Jacque L; Ho, Allen C; Olmos de Koo, Lisa C; Sahel, José‐Alain; Stanga, Paulo E; Thumann, Gabriele; Wang, Vizhong; Greenberg, Robert J

    2016-01-01

    Abstract Objective The purpose of this analysis was to compare observer‐rated tasks in patients implanted with the Argus II Retinal Prosthesis System, when the device is ON versus OFF. Methods The Functional Low‐Vision Observer Rated Assessment (FLORA) instrument was administered to 26 blind patients implanted with the Argus II Retinal Prosthesis System at a mean follow‐up of 36 months. FLORA is a multi‐component instrument that consists in part of observer‐rated assessment of 35 tasks completed with the device ON versus OFF. The ease with which a patient completes a task is scored using a four‐point scale, ranging from easy (score of 1) to impossible (score of 4). The tasks are evaluated individually and organised into four discrete domains, including ‘Visual orientation’, ‘Visual mobility’, ‘Daily life and ‘Interaction with others’. Results Twenty‐six patients completed each of the 35 tasks. Overall, 24 out of 35 tasks (69 per cent) were statistically significantly easier to achieve with the device ON versus OFF. In each of the four domains, patients’ performances were significantly better (p < 0.05) with the device ON versus OFF, ranging from 19 to 38 per cent improvement. Conclusion Patients with an Argus II Retinal Prosthesis implanted for 18 to 44 months (mean 36 months), demonstrated significantly improved completion of vision‐related tasks with the device ON versus OFF. PMID:26804484

  7. BIFURCATION OF FLOW AND MASS TRANSPORT IN A CURVED BLOOD VESSEL

    Institute of Scientific and Technical Information of China (English)

    TAN Wenchang(谭文长); WEI Lan(魏兰); ZHAO Yaohua(赵耀华); TAKASHI Masuoka

    2003-01-01

    A numerical analysis of flow and concentration fields of macromolecules in a slightly curved blood vessel was carried out. Based on these results, the effect of the bifurcation of a flow on the mass transport in a curved blood vessel was discussed. The macromolecules turned out to be easier to deposit in the inner part of the curved blood vessel near the critical Dean number. Once the Dean number is higher than the critical number, the bifurcation of the flow appears. This bifurcation can prevent macromolecules from concentrating in the inner part of the curved blood vessel. This result is helpful for understanding the possible correlations between the blood dynamics and atherosclerosis.

  8. Venous ligation: a novel strategy for glans enhancement in penile prosthesis implantation.

    Science.gov (United States)

    Hsu, Geng-Long; Hill, James W; Hsieh, Cheng-Hsing; Liu, Shih-Ping; Hsu, Chih-Yuan

    2014-01-01

    Although penile implantation remains a final solution for patients with refractory impotence, undesirable postoperative effects, including penile size reduction and cold sensation of the glans penis, remain problematic. We report results of a surgical method designed to avoid these problems. From 2003 to 2013, 35 consecutive patients received a malleable penile implant. Of these, 15 men (the enhancing group) were also treated with venous ligation of the retrocoronal venous plexus, deep dorsal vein, and cavernosal veins. The remaining 20 men formed the control group, treated with only a penile implant. Follow-up ranged from 1.1 to 10.0 years, with an average of 6.7 ± 1.5 years. Although preoperative glanular dimension did not differ significantly between the two groups, significant respective difference at one day and one year postoperatively was found in the glanular circumference (128.8 ± 6.8 mm versus 115.3 ± 7.2 mm and 130.6 ± 7.2 mm versus 100.5 ± 7.3 mm; both Ppenis dimension in implant patients.

  9. Measuring Quality of Life in Stroke Subjects Receiving an Implanted Neural Prosthesis for Drop Foot

    NARCIS (Netherlands)

    Kottink, Anke I.; IJzerman, Maarten J.; Groothuis-Oudshoorn, Catharina G.; Hermens, Hermie J.

    2010-01-01

    The aim was to determine if the treatment of a drop foot by means of an implantable two-channel peroneal nerve stimulator improves health-related quality of life (HRQoL). All subjects were measured at baseline and after a follow-up period of 12 and 26 weeks. Twenty-nine stroke survivors with chronic

  10. Argus II retinal prosthesis implantation with scleral flap and autogenous temporalis fascia as alternative patch graft material: a 4-year follow-up

    Science.gov (United States)

    Matet, Alexandre; Amar, Nawel; Mohand-Said, Saddek; Sahel, José-Alain; Barale, Pierre-Olivier

    2016-01-01

    Introduction The Argus II retinal prosthesis is composed of an epiretinal electrode array positioned over the macula and connected to an extrascleral electronics case via a silicone cable, running through a sclerotomy. During implantation, the manufacturer recommends to cover the sclerotomy site with a patch of processed human pericardium to prevent postoperative hypotony and conjunctival erosion by the underlying electronics case. Due to biomedical regulations prohibiting the use of this material in France, we developed an alternative technique combining a scleral flap protecting the sclerotomy and an autogenous graft of superior temporalis fascia overlying the electronics case. Methods The purpose of this study is to describe the 4-year outcomes of this modified procedure in three subjects who underwent Argus II Retinal Prosthesis System implantation. Clinical data consisting of intraocular pressure measurements and tolerance in terms of conjunctival erosion or inflammation were retrospectively assessed over a 4-year postoperative follow-up. Results None of the three patients implanted with the modified technique developed ocular hypotony over 4 years. A normal, transient conjunctival inflammation occurred during the first postoperative month but conjunctival erosion was not observed in any of the three patients over 4 years. Four years after implantation, the autogenous temporalis fascia graft remained well tolerated and the retinal prosthesis was functional in all three patients. Conclusion The combination of an autograft of superficial temporalis fascia and a scleral flap efficiently prevented leakage through the sclerotomy site, ocular hypotony, and conjunctival erosion by the extrascleral electronics case. This modified technique is suitable for the implantation of existing and forthcoming retinal prostheses. Superficial temporalis fascia may also be used as alternative to commercial tectonic tissues for scleral wound repair in clinical settings where they

  11. Heterogeneity of muscarinic receptor subtypes in cerebral blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Villalon, A.L.; Krause, D.N.; Ehlert, F.J.; Duckles, S.P. (Department of Pharmacology, College of Medicine, University of California, Irvine (USA))

    1991-07-01

    The identity and distribution of muscarinic cholinergic receptor subtypes and associated signal transduction mechanisms was characterized for the cerebral circulation using correlated functional and biochemical investigations. Subtypes were distinguished by the relative affinities of a panel of muscarinic antagonists, pirenzepine, AF-DX 116 (11-2-((2-(diethylaminomethyl)- 1-piperidinyl)acetyl)-5,11-dihydro-6H- pyrido(2,3-b)(1,4)benzodiazepine-6-one), hexahydrosiladifenidol, methoctramine, 4-diphenylacetoxy-N-methylpiperidine methobromide, dicyclomine, para-fluoro-hexahydrosiladifenidol and atropine. Muscarinic receptors characterized by inhibition of (3H)quinuclidinylbenzilate binding in membranes of bovine pial arteries were of the M2 subtype. In contrast pharmacological analysis of (3H)-quinuclidinylbenzilate binding in bovine intracerebral microvessels suggests the presence of an M4 subtype. Receptors mediating endothelium-dependent vasodilation in rabbit pial arteries were of the M3 subtype, whereas muscarinic receptors stimulating endothelium-independent phosphoinositide hydrolysis in bovine pial arteries were of the M1 subtype. These findings suggest that characteristics of muscarinic receptors in cerebral blood vessels vary depending on the type of vessel, cellular location and function mediated.

  12. Illustration of the heart and blood vessels in medieval times.

    Science.gov (United States)

    Khalili, Majid; Shoja, Mohammadali M; Tubbs, R Shane; Loukas, Marios; Alakbarli, Farid; Newman, Andrew J

    2010-08-06

    Throughout history, illustrations had played a key role in the promotion and evolution of medicine by providing a medium for transmission of scientific observations. Due to religious prohibitions, color drawings of the human body did not appear in medieval Persia and during the Islamic Golden Age. This tradition, however, has been overlooked with the publication of the first color atlas and text of human anatomy, Tashrihi Mansuri (Mansur's Anatomy), by Mansur ibn Ilyas in the fourteenth century AD. Written in Persian and containing several vivid illustrations of the human body, this book gained widespread attention by both scholars and lay persons. In this article, a brief history of Mansur's Anatomy and an English translation of selected sections from this book regarding the heart and blood vessels are presented.

  13. Vascular prosthesis implantation for treatment of isolated lilac artery aneurysm A 33-case report%人工血管移植治疗髂动脉瘤33例

    Institute of Scientific and Technical Information of China (English)

    王春喜; 胡海地; 宋清彬; 段志泉; 陈刚; 梁发启

    2009-01-01

    A total of 33 patients with isolated lilac artery aneurysms, 19 males and 14 females, who received treatment between January 1997 and June 2007, were retrospectively analyzed. Among these patients, 29 suffered from unilateral iliac artery aneurysm and 4 from bilateral iliac artery aneurysm. Under general anesthesia, all patients were subjected to aneurysmectomy, followed by vascular prosthesis implantation for vascular reconstruction. Results revealed that among 4 cases of bilateral iliac artery aneurysm, there was 1 case who was subjected to aorta-bilateral femoral artery vascular prosthesis implantation, and there were 3 cases who underwent aorta-bilateral lilac artery vascular prosthesis implantation; among 29 cases of unilateral lilac artery aneurysm, there was 1 case receiving aorta-common lilac artery vascular prosthesis implantation, 3 cases undergoing iliac-femoral artery vascular prosthesis implantation, 21 cases subjected to common-external iliac artery vascular prosthesis implantation, and 4 cases undertaking common -common lilac artery bypass. Color Doppler ultrasonic examination, spiral CT angiography, or digital subtraction arteriography was performed 3, 6 months, 1, 3, 5, 8, and 10 years after surgery. The mean follow-up time was 5 years. Three cases died of acute cerebral infarction, myocardial infarction, and traffic accident 3, 6, and 2 years after surgery, respectively. The remaining cases well survived as determined by no recurred Uiac artery aneurysm, anastomotic stoma stenosis or lower limb ischemia found. These results indicated that aneurysmectomy and subsequent vascular prosthesis implantation remained a good and primary means for treatment of isolated iliac artery aneurysm under the present medical condition.%回顾性分析1997-01/2007-06收治孤立性骼动脉瘤患者共33例,男19例,女14例,其中单侧髂动脉瘤29例,双侧4例.均在全身麻醉下行动脉瘤切除、人工血管移植血管重建.结果显示4

  14. Posterior enlargement of the small annulus during aortic valve replacement versus implantation of a small prosthesis.

    Science.gov (United States)

    Pugliese, P; Bernabei, M; Santi, C; Pasqué, A; Eufrate, S

    1984-07-01

    Twenty-two patients with a small aortic annulus were identified among 196 consecutive patients undergoing aortic valve replacement (AVR). The 11 patients in Group 1 underwent posterior enlargement aortic annuloplasty, and the 11 in Group 2 received a small aortic prosthesis (less than or equal to 21 mm). The two groups were unselected. Core hypothermia, cardioplegia, and local cooling were employed for all operations. Isolated AVR was performed in 3 patients in each group. In Group 1, the mean increase in diameter of the annulus was 4.82 mm, which resulted in a mean area increase of 169.91 mm2 (51.7%). Mean aortic cross-clamp times were 140.4 minutes and 93.5 minutes in Groups 1 and 2, respectively. There were 2 operative deaths in Group 1, and 1 operative and 1 late death in Group 2. Mean follow-up was 26.5 months for Group 1 and 43.4 months for Group 2. No thomboembolic or bleeding episodes have been recorded. Considerations and conclusions are offered from the study of this small series of patients.

  15. Performance of a newly developed implantable centrifugal blood pump.

    Science.gov (United States)

    Tsukiya, T; Taenaka, Y; Tatsumi, E; Takano, H

    2001-01-01

    The performance of the newly developed implantable centrifugal blood pump was investigated in vitro. The pump was developed with the end goal of building a versatile system that includes a left ventricular assist system with an internal secondary battery or an implantable biventricular assist system with two implantable blood pumps. The hydrodynamic characteristics and efficiency of the blood pump were evaluated, and the mechanical damage to the blood caused by the blood pump was assessed through a hemolysis test using fresh goat blood. The pump could generate 120 mm Hg at a flow rate of 5 L/min and a motor speed of 2,500 rpm. The electric input power to the pump was approximately 5 watts under these working conditions. The hemolysis caused by the pump was a bit higher than that by the former model, but stayed within an acceptable range. Performance of the pump in vitro was considered sufficient for a left ventricular assist device, although further design improvement is necessary in terms of hemolysis and system efficiency to improve biocompatibility of the pump.

  16. Venous Ligation: A Novel Strategy for Glans Enhancement in Penile Prosthesis Implantation

    Directory of Open Access Journals (Sweden)

    Geng-Long Hsu

    2014-01-01

    Full Text Available Although penile implantation remains a final solution for patients with refractory impotence, undesirable postoperative effects, including penile size reduction and cold sensation of the glans penis, remain problematic. We report results of a surgical method designed to avoid these problems. From 2003 to 2013, 35 consecutive patients received a malleable penile implant. Of these, 15 men (the enhancing group were also treated with venous ligation of the retrocoronal venous plexus, deep dorsal vein, and cavernosal veins. The remaining 20 men formed the control group, treated with only a penile implant. Follow-up ranged from 1.1 to 10.0 years, with an average of 6.7 ± 1.5 years. Although preoperative glanular dimension did not differ significantly between the two groups, significant respective difference at one day and one year postoperatively was found in the glanular circumference (128.8 ± 6.8 mm versus 115.3 ± 7.2 mm and 130.6 ± 7.2 mm versus 100.5 ± 7.3 mm; both P<0.05, radius (38.8 ± 2.7 mm versus 37.1 ± 2.8 mm and 41.5 ± 2.6 mm versus 33.8 ± 2.9 mm; latter P<0.01, and satisfaction rate (91.7% versus 53.3%, P<0.01 as well. Based on our results, selective venous ligation appears to enhance the glans penis dimension in implant patients.

  17. Measuring quality of life in stroke subjects receiving an implanted neural prosthesis for drop foot.

    Science.gov (United States)

    Kottink, Anke I; Ijzerman, Maarten J; Groothuis-Oudshoorn, Catharina G; Hermens, Hermie J

    2010-05-01

    The aim was to determine if the treatment of a drop foot by means of an implantable two-channel peroneal nerve stimulator improves health-related quality of life (HRQoL). All subjects were measured at baseline and after a follow-up period of 12 and 26 weeks. Twenty-nine stroke survivors with chronic hemiplegia with drop foot who fulfilled the predefined inclusion and exclusion criteria were included in the present randomized controlled trial. The intervention group received an implantable two-channel peroneal nerve stimulator for correction of their drop foot. The control group continued using their conventional walking device, consisting of an ankle-foot orthosis, orthopedic shoes, or no device. HRQoL was assessed in two different ways: (i) by taking descriptive measures, that is, the Short Form-36 (SF-36; generic measure) and the Disability Impact Profile (DIP; specific measure); and (ii) by obtaining preference-based utilities both measured with the time trade-off (direct way) and by calculating them from the EuroQol (EQ-5D) and SF-36. A significant positive effect of the implantable device was found on the physical functioning domain, the general health domain, and the physical component summary score of the SF-36. For the DIP, a significant improvement was found on the domains mobility, self-care, and psychological status in the intervention group. Regarding the preference-based utility measures, a significant effect was found for the utility index calculated from the EQ-5D. The implantable two-channel peroneal nerve stimulator seems to be efficient to improve HRQoL, mainly the domains related to physical functioning. A relation was present between the utility indexes calculated from the EQ-5D and SF-36.

  18. A review of surgical strategies for penile prosthesis implantation in patients with Peyronie’s disease

    Science.gov (United States)

    Anaissie, James

    2016-01-01

    The introduction of the inflatable penile prosthesis (IPP) has revolutionized the treatment of patients with both Peyronie’s disease (PD) and erectile dysfunction (ED). A thorough literature review was performed in order to review the surgical strategies used to treat PD, using the PubMed online database with the keywords “penile prosthesis”, “surgical management” and “Peyronie’s disease”. Patient satisfaction rates of 72–100% and partner satisfaction rates of 89% have been reported in the literature, although strong preoperative education may be needed to prepare patients for risks such as penile shortening, seen in up to 54% of patients. Three-piece IPPs are most commonly used, and when comparing the two most popular models (AMS 700 CX vs. Coloplast Titan), no significant differences were seen in functional outcomes or patient satisfaction. Simple insertion of an IPP has been shown to resolve curvature in 33–90% of patients, but surgeons may often need to also utilize ancillary straightening procedures for residual curvatures. Manual modeling can correct residual curvature with an 86–100% success rate, but with a 4% risk of urethral injury. When the post-modeling residual curvature exceeds 30 degrees, a plaque-releasing incision or plication is recommended to further reduce curvature. Grafting is recommended if the resulting incisional defect is larger than two centimeters. Alternative straightening techniques such as plication prior to IPP insertion, endoscopic plaque resection, the “scratch technique” and bone saw plaque incision have also been described. PMID:27298781

  19. The role of prosthetic abutment material on the stress distribution in a maxillary single implant-supported fixed prosthesis

    Energy Technology Data Exchange (ETDEWEB)

    Peixoto, Hugo Eduardo, E-mail: hugo.e.peixoto@hotmail.com [Implantology Team, Latin American Institute of Research and Education in Dentistry, Curitiba, Paraná (Brazil); Bordin, Dimorvan, E-mail: dimorvan_bordin@hotmail.com [Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903 (Brazil); Del Bel Cury, Altair A., E-mail: altcury@fop.unicamp.br [Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903 (Brazil); Silva, Wander José da, E-mail: wanderjose@fop.unicamp.br [Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903 (Brazil); Faot, Fernanda, E-mail: fernanda.faot@gmail.com [Department of Restorative Dentistry, School of Dentistry, Federal University of Pelotas, Gonçalves Chaves, 457, 2nd floor, Pelotas, Rio Grande do Sul 96015-560 (Brazil)

    2016-08-01

    Purpose: Evaluate the influence of abutment's material and geometry on stress distribution in a single implant-supported prosthesis. Materials and Methods: Three-dimensional models were made based on tomographic slices of the upper middle incisor area, in which a morse taper implant was positioned and a titanium (Ti) or zirconia (ZrN) universal abutments was installed. The commercially available geometry of titanium (T) and zirconia (Z) abutments were used to draw two models, TM1 and ZM1 respectively, which served as control groups. These models were compared with 2 experimental groups were the mechanical properties of Z were applied to the titanium abutment (TM2) and vice versa for the zirconia abutment (ZM2). Subsequently, loading was simulated in two steps, starting with a preload phase, calculated with the respective friction coefficients of each materials, followed by a combined preload and chewing force. The maximum von Mises stress was described. Data were analyzed by two-way ANOVA that considered material composition, geometry and loading (p < 0.05). Results: Titanium and zirconia abutments showed similar von Mises stresses in the mechanical part of the four models. The area with the highest concentration of stress was the screw thread, following by the screw body. The highest stress levels occurred in screw thread was observed during the preloading phase in the ZM1 model (931 MPa); and during the combined loading in the TM1 model (965 MPa). Statistically significant differences were observed for loading, the material × loading interaction, and the loading × geometry interaction (p < 0.05). Preloading contributed for 77.89% of the stress (p < 0.05). There were no statistically significant differences to the other factors (p > 0.05). Conclusion: The screw was the piece most intensely affected, mainly through the preload force, independent of the abutment's material. - Highlights: • The abutment's screw was the most impaired piece of the

  20. Stress distribution in fixed-partial prosthesis and peri-implant bone tissue with different framework materials and vertical misfit levels: a three-dimensional finite element analysis.

    Science.gov (United States)

    Bacchi, Ataís; Consani, Rafael L X; Mesquita, Marcelo F; dos Santos, Mateus B F

    2013-09-01

    The purpose of this study was to evaluate the influence of superstructure material and vertical misfits on the stresses created in an implant-supported partial prosthesis. A three-dimensional (3-D) finite element model was prepared based on common clinical data. The posterior part of a severely resorbed jaw with two osseointegrated implants at the second premolar and second molar regions was modeled using specific modeling software (SolidWorks 2010). Finite element models were created by importing the solid model into mechanical simulation software (ANSYS Workbench 11). The models were divided into groups according to the prosthesis framework material (type IV gold alloy, silver-palladium alloy, commercially pure titanium, cobalt-chromium alloy, or zirconia) and vertical misfit level (10 µm, 50 µm, and 100 µm) created at one implant-prosthesis interface. The gap of the vertical misfit was set to be closed and the stress values were measured in the framework, porcelain veneer, retention screw, and bone tissue. Stiffer materials led to higher stress concentration in the framework and increased stress values in the retention screw, while in the same circumstances, the porcelain veneer showed lower stress values, and there was no significant difference in stress in the peri-implant bone tissue. A considerable increase in stress concentration was observed in all the structures evaluated within the misfit amplification. The framework material influenced the stress concentration in the prosthetic structures and retention screw, but not that in bone tissue. All the structures were significantly influenced by the increase in the misfit levels.

  1. Blood Vessel Normalization in the Hamster Oral Cancer Model for Experimental Cancer Therapy Studies

    Energy Technology Data Exchange (ETDEWEB)

    Ana J. Molinari; Romina F. Aromando; Maria E. Itoiz; Marcela A. Garabalino; Andrea Monti Hughes; Elisa M. Heber; Emiliano C. C. Pozzi; David W. Nigg; Veronica A. Trivillin; Amanda E. Schwint

    2012-07-01

    Normalization of tumor blood vessels improves drug and oxygen delivery to cancer cells. The aim of this study was to develop a technique to normalize blood vessels in the hamster cheek pouch model of oral cancer. Materials and Methods: Tumor-bearing hamsters were treated with thalidomide and were compared with controls. Results: Twenty eight hours after treatment with thalidomide, the blood vessels of premalignant tissue observable in vivo became narrower and less tortuous than those of controls; Evans Blue Dye extravasation in tumor was significantly reduced (indicating a reduction in aberrant tumor vascular hyperpermeability that compromises blood flow), and tumor blood vessel morphology in histological sections, labeled for Factor VIII, revealed a significant reduction in compressive forces. These findings indicated blood vessel normalization with a window of 48 h. Conclusion: The technique developed herein has rendered the hamster oral cancer model amenable to research, with the potential benefit of vascular normalization in head and neck cancer therapy.

  2. Influence of cerebral blood vessel movements on the position of perivascular synapses

    Science.gov (United States)

    DeFelipe, Javier

    2017-01-01

    Synaptic activity is regulated and limited by blood flow, which is controlled by blood vessel dilation and contraction. Traditionally, the study of neurovascular coupling has mainly focused on energy consumption and oxygen delivery. However, the mechanical changes that blood vessel movements induce in the surrounding tissue have not been considered. We have modeled the mechanical changes that movements of blood vessels cause in neighboring synapses. Our simulations indicate that synaptic densities increase or decrease during vascular dilation and contraction, respectively, near the blood vessel walls. This phenomenon may alter the concentration of neurotransmitters and vasoactive substances in the immediate vicinity of the vessel wall and thus may have an influence on local blood flow. PMID:28199396

  3. Isokinetic force-velocity curves in patients following implantation of an individual total hip prosthesis.

    Science.gov (United States)

    Horstmann, T; Martini, F; Knak, J; Mayer, F; Sell, S; Zacher, J; Küsswetter, W

    1994-01-01

    There are only a few studies which could support conclusions concerning the strength of the muscles surrounding the hip joint and especially concerning the strength relationships following implantation of endoprostheses. The aim of this study was to examine the post-operative course of strength deficits in this musculature compared to clinical parameters. Fifty-eight patients between 30 and 67 years of age, in whom individual total hip prostheses were implanted, were clinically examined prior, 9 weeks and 6 months after surgery. Moreover, the maximum isometric strengths of abductors, flexors, and rotator muscles as well as maximum isokinetic strengths of the extensors and flexor musculature at 60 degrees/s and 120 degrees/s were measured. The flexor and extensor musculature already showed a clear increase in maximum strength after 9 weeks and 6 months. By contrast, the isometric strengths of the rotators increased only slightly, the abductor strength decreased after 9 weeks to below the preoperative baseline level and attained this level again only after 6 months. The clinical parameters Trendelenburg sign, limping, and walking capacity were clearly improved after 6 months, but no correlation to the abductor strength could be demonstrated. It is concluded that limp-free gait can be attained even without maximum strength increase in the abductors, which are important for fluid gait, at least for short distances. The importance of regular training of the rotator and abductor musculature in coxarthrosis is emphasized to delay limitation of movement and decreased strength in the sense of a capsule pattern.

  4. Argus II retinal prosthesis implantation with scleral flap and autogenous temporalis fascia as alternative patch graft material: a 4-year follow-up

    Directory of Open Access Journals (Sweden)

    Matet A

    2016-08-01

    Full Text Available Alexandre Matet,1,2 Nawel Amar,1,2 Saddek Mohand-Said,1–4 José-Alain Sahel,1–7 Pierre-Olivier Barale1,2 1INSERM and DHOS, CHNO des Quinze-Vingts, 2Sorbonne Universités, UPMC Univ Paris 6, Institut de la Vision, 3INSERM, 4CNRS, Paris, France; 5Institute of Ophthalmology, University College London, London, UK; 6Fondation Ophtalmologique Adolphe de Rothschild, 7Académie des Sciences, Institut de France, Paris, France Introduction: The Argus II retinal prosthesis is composed of an epiretinal electrode array positioned over the macula and connected to an extrascleral electronics case via a silicone cable, running through a sclerotomy. During implantation, the manufacturer recommends to cover the sclerotomy site with a patch of processed human pericardium to prevent postoperative hypotony and conjunctival erosion by the underlying electronics case. Due to biomedical regulations prohibiting the use of this material in France, we developed an alternative technique combining a scleral flap protecting the sclerotomy and an autogenous graft of superior temporalis fascia overlying the electronics case. Methods: The purpose of this study is to describe the 4-year outcomes of this modified procedure in three subjects who underwent Argus II Retinal Prosthesis System implantation. Clinical data consisting of intraocular pressure measurements and tolerance in terms of conjunctival erosion or inflammation were retrospectively assessed over a 4-year postoperative follow-up. Results: None of the three patients implanted with the modified technique developed ocular hypotony over 4 years. A normal, transient conjunctival inflammation occurred during the first postoperative month but conjunctival erosion was not observed in any of the three patients over 4 years. Four years after implantation, the autogenous temporalis fascia graft remained well tolerated and the retinal prosthesis was functional in all three patients. Conclusion: The combination of an

  5. The use of BDNF to enhance the patency rate of small-diameter tissue-engineered blood vessels through stem cell homing mechanisms.

    Science.gov (United States)

    Zeng, Wen; Wen, Can; Wu, Yangxiao; Li, Li; Zhou, Zhenhua; Mi, Jianhong; Chen, Wen; Yang, Mingcan; Hou, Chunli; Sun, Jiansen; Zhu, Chuhong

    2012-01-01

    The patency rate of small-diameter tissue-engineered blood vessels is the determinant for their application in coronary artery bypass grafting. The coronary artery is innervated by vagus nerves. The origin of vagus nerves is rich in brain-derived neurotrophic factors (BDNF). We have investigated whether BDNF could improve the patency rate of small-diameter tissue-engineered blood vessels through promoting stem cell homing and paracrine activity. In vitro, we isolated early and late endothelial progenitor cells (EPCs) and found BDNF could promote single clone formation and paracrine function of EPCs, and could also induce the proliferation, migration and differentiation of late EPCs. BDNF could enhance the capturing of EPCs in parallel-plate flow chamber. Flow cytometric analysis and laser-scanning confocal microscope showed BDNF could enhance the mobilization and homing of C57BL/6 mouse EPCs after wire injury. Based on it, BDNF was coupled to the lumen surface of the blood vessel matrix material incubated with collagen through SPDP to construct BDNF-modified small-diameter tissue-engineered blood vessel. The blood vessel patency rate was significantly higher than that of control group 8 weeks after implantation in rats and the endothelialization level was superior to control. These results demonstrate that BDNF can effectively improve patency of small-diameter tissue-engineered blood vessels through stem cell homing and paracrine, and it is expected to play an important role in the construction of substitutes for coronary artery bypass grafting.

  6. The vascular Ca2+-sensing receptor regulates blood vessel tone and blood pressure.

    Science.gov (United States)

    Schepelmann, M; Yarova, P L; Lopez-Fernandez, I; Davies, T S; Brennan, S C; Edwards, P J; Aggarwal, A; Graça, J; Rietdorf, K; Matchkov, V; Fenton, R A; Chang, W; Krssak, M; Stewart, A; Broadley, K J; Ward, D T; Price, S A; Edwards, D H; Kemp, P J; Riccardi, D

    2016-02-01

    The extracellular calcium-sensing receptor CaSR is expressed in blood vessels where its role is not completely understood. In this study, we tested the hypothesis that the CaSR expressed in vascular smooth muscle cells (VSMC) is directly involved in regulation of blood pressure and blood vessel tone. Mice with targeted CaSR gene ablation from vascular smooth muscle cells (VSMC) were generated by breeding exon 7 LoxP-CaSR mice with animals in which Cre recombinase is driven by a SM22α promoter (SM22α-Cre). Wire myography performed on Cre-negative [wild-type (WT)] and Cre-positive (SM22α)CaSR(Δflox/Δflox) [knockout (KO)] mice showed an endothelium-independent reduction in aorta and mesenteric artery contractility of KO compared with WT mice in response to KCl and to phenylephrine. Increasing extracellular calcium ion (Ca(2+)) concentrations (1-5 mM) evoked contraction in WT but only relaxation in KO aortas. Accordingly, diastolic and mean arterial blood pressures of KO animals were significantly reduced compared with WT, as measured by both tail cuff and radiotelemetry. This hypotension was mostly pronounced during the animals' active phase and was not rescued by either nitric oxide-synthase inhibition with nitro-l-arginine methyl ester or by a high-salt-supplemented diet. KO animals also exhibited cardiac remodeling, bradycardia, and reduced spontaneous activity in isolated hearts and cardiomyocyte-like cells. Our findings demonstrate a role for CaSR in the cardiovascular system and suggest that physiologically relevant changes in extracellular Ca(2+) concentrations could contribute to setting blood vessel tone levels and heart rate by directly acting on the cardiovascular CaSR.

  7. Determination of the critical buckling pressure of blood vessels using the energy approach.

    Science.gov (United States)

    Han, Hai-Chao

    2011-03-01

    The stability of blood vessels under lumen blood pressure is essential to the maintenance of normal vascular function. Differential buckling equations have been established recently for linear and nonlinear elastic artery models. However, the strain energy in bent buckling and the corresponding energy method have not been investigated for blood vessels under lumen pressure. The purpose of this study was to establish the energy equation for blood vessel buckling under internal pressure. A buckling equation was established to determine the critical pressure based on the potential energy. The critical pressures of blood vessels with small tapering along their axis were estimated using the energy approach. It was demonstrated that the energy approach yields both the same differential equation and critical pressure for cylindrical blood vessel buckling as obtained previously using the adjacent equilibrium approach. Tapering reduced the critical pressure of blood vessels compared to the cylindrical ones. This energy approach provides a useful tool for studying blood vessel buckling and will be useful in dealing with various imperfections of the vessel wall.

  8. MACROMICROSCOPIC AND ULTRAMICROSCOPIC CHARACTERISTICS OF THE HART AND ITS BLOOD VESSELS IN MICE EHRLICHIOSIS INFECTION

    Directory of Open Access Journals (Sweden)

    Pokhil S. I.

    2013-12-01

    Full Text Available The macromicroscopic, ultramicroscopic studying change’s in the hart and its blood vessels in unlinear immunocomprometive laboratory male and female mice with the experimental ehrlichiosis is presented in this article. The cardiac destructive and degenerative changes,cardiomyopathy, cardiosclerosis had been established inexperimental animal group’s. The blood vessels endothelial lieyr disorganization, stasis, thrombosis has been noted.

  9. [Effects of high intensity focused ultrasound with SonoVue on blood vessels pathological examinations].

    Science.gov (United States)

    Qin, Yan; Bai, Jin; Li, Faqi; Wang, Zhibiao

    2010-12-01

    The injury of tumor blood vessels will break up the nutrition supply for the tumor. In this paper, we investigated the effects exerted by high intensity focused ultrasound (HIFU) combined with ultrasound microbubble agent on blood vessels. Ultrasound diagnosis was used to find the goat hepatic blood vessels each being approximately 3mm in diameter. HIFU was focused on the blood vessels. The acoustic power was 250W; HIFU irradiating Mode was line scan (the length of the line: 10 mm; speed: 3 mm/s; irradiating time: 30s). In the experimental group, 0.03 ml/kg SonoVue was injected into the goat before HIFU irradiation,while normal saline was given to the control group. The goats were killed at 24h after HIFU irradiation, then goat liver tissues and blood vessels of target area were taken out. HE staining and Victoria's blue and Ponceau's staining of tissue section showed that the endothelial cells of blood vessels dropped off and became necrosed, and the continuity of blood vessels was interrupted. HIFU combined with SonoVue will damage large blood vessels on HIFU focus, but there is no evident discrepancy between the group with SonoVue and the group without SonoVue.

  10. [Influence of implant position of a hip prosthesis on alignment exemplified by the CLS shaft].

    Science.gov (United States)

    Schneider, U; Breusch, S J; Thomsen, M; Wirtz, D C; Lukoschek, M

    2002-01-01

    We performed a clinical and radiological analysis to evaluate the significance of the stem position of cementless CLS components with respect to function and survival. We used patient material from a multi-center study of 3,732 CLS stems with a mean follow-up of 43 months (range: 12-142 months). The clinical outcome was assessed using Merle D'Aubigné Scores and stem alignment was determined as the deviation of the longitudinal stem axis from the longitudinal femur axis. We found no correlation between stem alignment and function, survival, implant migration or periprosthetic radiolucent lines. In patients with rheumatoid arthritis and hip ankylosis the neutral stem position was less often achieved than in patients with other diagnoses. The results of our study cast doubt on whether the varus position of the femoral component of cementless tapered CLS-type stem designs is as critical as in cemented total hip arthroplasty.

  11. Does the etiology affect the outcome and satisfaction rates of penile prosthesis implantation surgery?

    Science.gov (United States)

    Bozkurt, Ibrahim Halil; Arslan, Burak; Kozacioglu, Zafer; Yonguc, Tarik; Degirmenci, Tansu; Gunlusoy, Bulent; Minareci, Suleyman

    2014-11-01

    Our aim was to compare the outcomes and satisfaction rates of men undergoing penile prostheses implantation (PPI) secondary to radical prostatectomy (RP) and other causes of vasculogenic erectile dysfunction (ED). A total of 142 patients, of whom 60 underwent PPI due to ED following RP (Group 1) and 82 underwent PPI due to ED with other vasculogenic causes (Group 2) were included in this study. The preoperative erectile status was evaluated with the International Index of Erectile Function (IIEF). The satisfaction of patients and partners were evaluated by a telephone interview using Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) questionnaire and Erectile Dysfunction Inventory of Treatment Satisfaction Partner Survey. Preoperative mean IIEF scores were significantly lower in Group 1 (17.5 ± 6.4 vs. 24.2 ± 5.1, p = 0.01). For Groups 1 and 2, the mean EDITS scores of the patients were 58 ± 10 and 71 ± 8, respectively, and that for the partners were 46 ± 8 and 65 ± 7, respectively. Group 1 had significantly lower scores both for the EDITS and the EDITS Partner Survey (p = 0.03, p = 0.01, respectively). Patients who had undergone RP and their partners were found to have lower satisfaction rates compared to patients with other causes of vasculogenic ED who had penile implant surgery. From this point of view, it is important to know the patient's expectations about the treatment outcomes and a preoperative psychological and sexual counseling should be managed for possible treatment alternatives after RP.

  12. Implante transapical de valva aórtica: resultados de uma nova prótese brasileira Transapical aortic valve implantation: results of a brazilian prosthesis

    Directory of Open Access Journals (Sweden)

    Diego Felipe Gaia

    2010-09-01

    procedimento alternativo.OBJECTIVE: The aortic valve replacement is a routine procedure with acceptable risk, but in some cases, such a risk can justify contraindication. The minimally invasive transcatheter aortic valve implantation has been viable, with lower morbidity and mortality. The aim of this study was to develop a national catheter-mounted aortic bioprosthesis for the aortic position implant. METHODS: After animal studies, 14 patients with high EuroSCORE underwent transcatheter aortic valve implantation. Median Logistic EuroSCORE was 43.7%. Four patients presented with dysfunctional bioprosthesis, remaining ones presented calcified aortic stenosis. All patients presented symptoms. Procedures were performed in a hybrid OR under fluoroscopic and echocardiography guidance. Using a left minithoracotomy the prosthesis was implanted through the ventricular apex under ventricular pacing or hemorrhagic shock, after aortic valvoplasty. Echocardiograph and angiograph controls were performed, and the patients were referred to ICU. RESULTS: Implant was feasible in 13 cases. There were no intra-operative deaths. Median peak transvalvular aortic gradient reduced to 25.0 mmHg, and left ventricular function improved in the first seven post-operative days. Paravalvular aortic regurgitation was mild and present in 71%. No definitive pacemaker was needed. There was no peripheral vascular complication. Overall mortality was 42%. CONCLUSION: The transapical implantation of cathetermounted bioprosthesis was a feasible procedure. Long term follow-up is mandatory in order to access efficacy and indications.

  13. Endoscope-Assisted and Controlled Argus II Epiretinal Prosthesis Implantation in Late-Stage Retinitis Pigmentosa: A Report of 2 Cases.

    Science.gov (United States)

    Özmert, Emin; Demirel, Sibel

    2016-01-01

    Several different approaches for restoring sight in subjects who are blind due to outer retinal degeneration are currently under investigation, including stem cell therapy, gene therapy, and visual prostheses. Although many different types of visual prostheses have shown promise, to date, the Argus II Epiretinal Prosthesis System, developed in a clinical setting over the course of 10 years, is the world's first and only retinal prosthesis that has been approved by the United States Food and Drug Administration (FDA) and has been given the CE-Mark for sale within the European Economic Area (EEA). The incidence of serious adverse events from Argus II implantation decreased over time after minor changes in the implant design and improvements in the surgical steps used for the procedure had been made. In order to further decrease the scleral incision-related complications and enhance the assessment of the tack position and the contact between the array and the inner macular surface, we used an ophthalmic endoscope during the regular course of Argus II implantation surgery in 2 patients with late-stage retinitis pigmentosa in an attempt to improve the anatomical and functional outcomes.

  14. Endoscope-Assisted and Controlled Argus II Epiretinal Prosthesis Implantation in Late-Stage Retinitis Pigmentosa: A Report of 2 Cases

    Directory of Open Access Journals (Sweden)

    Emin Özmert

    2016-12-01

    Full Text Available Several different approaches for restoring sight in subjects who are blind due to outer retinal degeneration are currently under investigation, including stem cell therapy, gene therapy, and visual prostheses. Although many different types of visual prostheses have shown promise, to date, the Argus II Epiretinal Prosthesis System, developed in a clinical setting over the course of 10 years, is the world’s first and only retinal prosthesis that has been approved by the United States Food and Drug Administration (FDA and has been given the CE-Mark for sale within the European Economic Area (EEA. The incidence of serious adverse events from Argus II implantation decreased over time after minor changes in the implant design and improvements in the surgical steps used for the procedure had been made. In order to further decrease the scleral incision-related complications and enhance the assessment of the tack position and the contact between the array and the inner macular surface, we used an ophthalmic endoscope during the regular course of Argus II implantation surgery in 2 patients with late-stage retinitis pigmentosa in an attempt to improve the anatomical and functional outcomes.

  15. Tumor blood vessels formation in osteosarcoma:vasculogenesis mimicry

    Institute of Scientific and Technical Information of China (English)

    蔡宣松; 贾永伟; 梅炯; 汤如勇

    2004-01-01

    Background Osteosarcoma is characterized by high neovascularization and a high propensity for metastasis through bloodstream. This study was to examine whether there is evidence for vasculogenic mimicry in osteosarcoma and to illustrate mechanism of tumor blood vessels formation in osteosarcoma.Methods Osteosarcoma cell lines (U-2OS) were tested for their ability to form tubular networks in three-dimensional culture containing type Ⅰ collagen. The structures of the tubular networks were observed with phase contrast microscope and transmission electron microscope (TEM). Morphometric studies using hematoxylin and eosin (HE) stain and CD31 immunohistochemical stain to show tumor-lined channels in human osteosarcoma were also performed.Results Observation with light microscope and TEM showed that highly aggressive osteosarcoma cell lines (U-2OS) formed networks containing channels when grown in three-dimensional culture containing type Ⅰ collagen, in the absence of endothelial cells or fibroblasts. Morphometric observation using HE stain and CD31 immunohistochemical stain showed that tumor cell-lined channels were also detected in vivo in osteosarcoma; by comparison, all vascular areas in the pedicel of osteochondroma or outside osteochondroma were endothelial-lined.Conclusion These observations strongly suggest that aggressive osteosarcoma cells may generate vascular channels that facilitate tumor perfusion independent of tumor angiogenesis and have the ability of vasculogenic mimicry.

  16. 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.

  17. Bare metal or drug-eluting stent implantation in last remaining vessel PCI? A serious dilemma.

    Science.gov (United States)

    Zhang, Lei; Zhu, Jianhua; Kiemeneij, Ferdinand

    2009-04-01

    This case report describes the treatment of an old male diabetic patient with last remaining vessel coronary artery disease and poor left ventricular function. In presence of an old occlusion of the left main coronary artery, a subtotal stenosis of a dominant right coronary artery required angioplasty. After ample consideration it was decided to implant a bare metal stent (BMS) instead of a drug-eluting stent (DES). The major reason was the fear for early discontinuation of clopidogrel in case a drug-eluting stent was placed. The procedure and follow-up are described followed by an overview of current literature concerning similar pathology.

  18. Estimation of vessel diameter and blood flow dynamics from laser speckle images

    DEFF Research Database (Denmark)

    Postnov, Dmitry D.; Tuchin, Valery V.; Sosnovtseva, Olga

    2016-01-01

    Laser speckle imaging is a rapidly developing method to study changes of blood velocity in the vascular networks. However, to assess blood flow and vascular responses it is crucial to measure vessel diameter in addition to blood velocity dynamics. We suggest an algorithm that allows for dynamical...... masking of a vessel position and measurements of it's diameter from laser speckle images. This approach demonstrates high reliability and stability....

  19. Morphological evaluation of the cerebral blood vessels in the late gestation fetal sheep following hypoxia in utero.

    Science.gov (United States)

    Baburamani, Ana A; Lo, Camden; Castillo-Melendez, Margie; Walker, David W

    2013-01-01

    Hypoxia can significantly contribute to the development of permanent brain injury in the term neonate; however the response of cerebral blood vessels is not well understood. This study aimed to quantitatively measure vascular density and morphology using laminin immunohistochemistry as a marker of blood vessels, and determine the effects of a single, severe bout of hypoxia (umbilical cord occlusion, UCO) late in gestation on the developing cerebrovasculature in fetal sheep. At 124-126 days gestation singleton fetal sheep underwent surgery for implantation of catheters and placement of an inflatable cuff around the umbilical cord. A 10 min UCO or sham UCO (n=5) occurred at 132 days gestation. Fetal brains were collected at 24 h (n=5) or 48 h (n=4) after UCO for vascular density and morphology analysis of laminin immunohistochemistry. 48 h following a single, brief bout of severe hypoxia late in gestation decreased vascular density was seen in the caudate nucleus and no changes in vascular morphology occurred. However closer analysis revealed a significant shift in the frequency of smaller (≤10 μm) to larger (≤100 μm) perimeter blood vessels in periventricular and subcortical white matter. Close examination of the frequency distribution of vascular perimeter highlights that alterations in vascular morphology persist in the near term fetal brain for up to 48 h following a brief (10 min) hypoxia in white but not gray matter. These findings suggest that the near term brain may still be vulnerable to white matter injury following in utero hypoxia.

  20. Blood Vessels Extraction in Retinal Image Using New Generation Curvelet Transform and Adaptive Weighted Morphology Operators

    Directory of Open Access Journals (Sweden)

    Saleh Shahbeig

    2013-02-01

    Full Text Available According to many medical and biometric applications of retinal images, the automatic and accurate extraction of the retinal blood vessels is very important. In this paper, an effective method is introduced to extract the blood vessels from the background of colored images of retina. In this algorithm, by applying the equalizer function on the retinal images, the brightness of the images is considerably uniformed. Because of high ability of Curvelet transform in introducing image borders in various scale and directions, borders and, consequently the contrast of retinal images can be enhanced. Therefore, the enhanced retinal image can be prepared for the extraction of blood vessels by improving Curvelet coefficients of the retinal images, adaptively and locally. Since the blood vessels in retinal images are distributed in various directions, we use the adaptive weighted morphology operators to extract the blood vessels from retinal images. Morphology operators based on reconstruction are used to refine the appeared frills with the size of smaller than arterioles in images properly. Finally, by analyzing the connected component in the images and applying adaptive filter on the components locally, all residual frills are refined from the images. The proposed algorithm in this paper has been evaluated by the images in the DRIVE database. The results how that the blood vessels are extracted from background of the retinal images of DRIVE database with the high accuracy of 96.15%, which in turn shows the high ability of the proposed algorithm in extracting the retinal blood vessels.

  1. Evaluation of accuracy of casts of multiple internal connection implant prosthesis obtained from different impression materials and techniques: an in vitro study.

    Science.gov (United States)

    Pujari, Malesh; Garg, Pooja; Prithviraj, D R

    2014-04-01

    Movement of impression copings inside the impression material using a direct (open tray) impression technique during clinical and laboratory phases may cause inaccuracy in transferring the 3-dimensional spatial orientation of implants intraorally to the cast. Consequently, the prosthesis may require corrective procedures. This in vitro study evaluated the accuracy of 3 different impression techniques using polyether and vinyl polysiloxane (VPS) impression material to obtain a precise cast for multiple internal connection implants. A reference acrylic resin model with 4 internal connection implants was fabricated. Impressions of the reference model were made using 3 different techniques and 2 different impression materials. The study consisted of 24 specimens divided into 6 groups of 4 each. Impressions were poured with ADA type IV stone (Kalrock, Kalabhai Karson Pvt Ltd, Mumbai, India). All casts were evaluated for the positional accuracy (mm) of the implant replica heads using a profile projector. These measurements were compared to the measurements calculated on the reference resin model, which served as a control. Data were analyzed with 2-way analysis of variance (ANOVA) followed by Bonferroni multiple comparison procedures to evaluate group means. The results revealed significant difference for anterior implant distance between the 2 impression materials (P techniques (P technique. For posterior implants, the results suggested no significant difference between the 2 impression materials (P ≥ .05). Although results were not statistically significant, the polyether impression material showed the lowest mean variation as compared to the VPS impression material. However, there was a significant difference among the 3 different techniques (P techniques, the lowest mean variation between 2 posterior implants was found in the splinted technique. Casts obtained from impression techniques using square impression copings splinted together with autopolymerizing acrylic

  2. Implante transcateter de valva aórtica: resultados atuais do desenvolvimento e implante de um nova prótese brasileira Transcatheter aortic valve implantation: results of the current development and implantation of a new Brazilian prosthesis

    Directory of Open Access Journals (Sweden)

    Diego Felipe Gaia

    2011-09-01

    . Minimally invasive transcatheter aortic valve implantation has emerged as an alternative, with lower morbidity and mortality. The aim of this study was clinical, safety and efficacy assessment. METHODS: Thirty-three high risk patients underwent transcatheter balloon expandable aortic valve implantation. Mean Logistic EuroScore risk was 39.30% and STS score 30.28%. Eight patients presented with dysfunctional bioprosthesis, remaining ones presented calcified aortic stenosis. Procedures were performed in a hybrid OR under fluoroscopic and echocardiography guidance. Using a left minithoracotomy the prosthesis were implanted trough the ventricular apex under rapid ventricular pacing or hemorrhagic shock. Echocardiographic and angiographic controls were performed. RESULTS: Implant was feasible in 30 cases. Three conversions occured. There was only one case of operative death. Median transvalvular aortic gradient reduced from 43.58 mmHg to 10.54 mmHg. Left ventricular function improved in the first 7 postoperative days. Paravalvular aortic regurgitation was mild and present in 30.30%. One case presented major vascular complication and another one permanent pacemaker implant. One major stroke case occurred. Overall 30-day mortality was 18.18%. CONCLUSION: The transapical implantation of catheter mounted bioprosthesis is a safe procedure with acceptable midterm results. Long term follow-up with increased sample power is mandatory in order to access hemodynamic, life quality and survival

  3. Laser optical method of visualizing cutaneous blood vessels and its applications in biometry and photomedicine

    Science.gov (United States)

    Asimov, M. M.; Asimov, R. M.; Rubinov, A. N.

    2011-05-01

    We propose and examine a new approach to visualizing a local network of cutaneous blood vessels using laser optical methods for applications in biometry and photomedicine. Various optical schemes of the formation of biometrical information on the architecture of blood vessels of skin tissue are analyzed. We developed an optical model of the interaction of the laser radiation with the biological tissue and a mathematical algorithm of processing of measurement results. We show that, in medicine, the visualization of blood vessels makes it possible to calculate and determine regions of disturbance of blood microcirculation and to control tissue hypoxia, as well as to maintain the local concentration of oxygen at a level necessary for the normal cellular metabolism. We propose noninvasive optical methods for modern photomedicine and biometry for diagnostics and elimination of tissue hypoxia and for personality identification and verification via the pattern of cutaneous blood vessels.

  4. 改良式肌锥内义眼台植入术%The improved orbital implantion with hydroxyapatite prosthesis in the muscular pyramid

    Institute of Scientific and Technical Information of China (English)

    康黔; 王琼; 王建辉

    2011-01-01

    目的 观察改良式肌锥内羟基磷灰石(HA)义眼台植入的临床效果.方法 96例眼球摘除和眼内容摘除术后采取HA义眼台植入肌锥内,义眼台前部采用巩膜或阔筋膜完全包埋.结果 术后随访3~24个月,无发生义眼台感染、暴露及脱出者,活动度达到预期目的.外观饱满,双眼对称性好.结论 采取HA义眼台植入肌锥内,前部采用巩膜或阔筋膜包埋同定的方法,并发症少、疗效良好.%Objective To observe the effect of improved orbital implantation with hydroxyapatite prosthesis in the muscular pyramid. Methods The hydroxyapatite prosthesis encapsulated with sclera or fascia lata of 96 patients with enucleation or evisceration of eyeball were implanted in the muscular pyramid. Results The follow-up period of the patients was from 3 months to 24 months. No one cases of infection,exposure and extrusion occurred. The implant migration and extrusion achieved the desired purpose. Conclusion The improved HA implant surgery with rare complications and satisfactory therapeutic effect was easy to operate and worth to clinical generalization.

  5. 21 CFR 878.3550 - Chin prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Chin prosthesis. 878.3550 Section 878.3550 Food... DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3550 Chin prosthesis. (a) Identification. A chin prosthesis is a silicone rubber solid device intended to be implanted to augment...

  6. 21 CFR 878.3680 - Nose prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nose prosthesis. 878.3680 Section 878.3680 Food... DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3680 Nose prosthesis. (a) Identification. A nose prosthesis is a silicone rubber solid device intended to be implanted to augment...

  7. 21 CFR 878.3590 - Ear prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and... GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An ear prosthesis is a silicone rubber solid device intended to be implanted to reconstruct the...

  8. 21 CFR 876.3750 - Testicular prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Testicular prosthesis. 876.3750 Section 876.3750...) MEDICAL DEVICES GASTROENTEROLOGY-UROLOGY DEVICES Prosthetic Devices § 876.3750 Testicular prosthesis. (a) Identification. A testicular prosthesis is an implanted device that consists of a solid or gel-filled...

  9. Solitonlike attractor for blood vessel tip density in angiogenesis

    Science.gov (United States)

    Bonilla, L. L.; Carretero, M.; Terragni, F.

    2016-12-01

    Recently, numerical simulations of a stochastic model have shown that the density of vessel tips in tumor-induced angiogenesis adopts a solitonlike profile [Sci. Rep. 6, 31296 (2016), 10.1038/srep31296]. In this work, we derive and solve the equations for the soliton collective coordinates that indicate how the soliton adapts its shape and velocity to varying chemotaxis and diffusion. The vessel tip density can be reconstructed from the soliton formulas. While the stochastic model exhibits large fluctuations, we show that the location of the maximum vessel tip density for different replicas follows closely the soliton peak position calculated either by ensemble averages or by solving an alternative deterministic description of the density. The simple soliton collective coordinate equations may also be used to ascertain the response of the vessel network to changes in the parameters and thus to control it.

  10. The use of near-infrared light for safe and effective visualization of subsurface blood vessels to facilitate blood withdrawal in children

    NARCIS (Netherlands)

    Cuper, Natascha J.; Klaessens, John H. G.; Jaspers, Joris E. N.; de Roode, Rowland; Noordmans, Herke Jan; de Graaff, Jurgen C.; Verdaasdonk, Rudolf M.

    2013-01-01

    Obtaining access to blood vessels can be difficult, especially in children. Visualization of subsurface blood vessels might be a solution. Ultrasound and visible light have been used to this purpose, but have some drawbacks. Near-infrared light might be a better option since subsurface blood vessels

  11. Primary Reconstruction of Completely Biologic Tissue Engineered Blood Vessel and Related Basic Research

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionIt is a usual regiment to execute surgical treatments to vascular diseases, which need much more vessels than the acquirable natural ones. This requires necessary vessel substitutes of tissue engineered blood vessels (TEBV)~([1]). It is one of the present research focuses to reconstruct TEBV with decellularised vascular scaffolds~([2, 3]).Despite the fact~([1,2]) that some of the large-diameter (>5 mm internal diameter) TEBV have been successfully developed from polymers such as Dacron or expa...

  12. High-resolution ultrasound imaging and noninvasive optoacoustic monitoring of blood variables in peripheral blood vessels

    Science.gov (United States)

    Petrov, Irene Y.; Petrov, Yuriy; Prough, Donald S.; Esenaliev, Rinat O.

    2011-03-01

    Ultrasound imaging is being widely used in clinics to obtain diagnostic information non-invasively and in real time. A high-resolution ultrasound imaging platform, Vevo (VisualSonics, Inc.) provides in vivo, real-time images with exceptional resolution (up to 30 microns) using high-frequency transducers (up to 80 MHz). Recently, we built optoacoustic systems for probing radial artery and peripheral veins that can be used for noninvasive monitoring of total hemoglobin concentration, oxyhemoglobin saturation, and concentration of important endogenous and exogenous chromophores (such as ICG). In this work we used the high-resolution ultrasound imaging system Vevo 770 for visualization of the radial artery and peripheral veins and acquired corresponding optoacoustic signals from them using the optoacoustic systems. Analysis of the optoacoustic data with a specially developed algorithm allowed for measurement of blood oxygenation in the blood vessels as well as for continuous, real-time monitoring of arterial and venous blood oxygenation. Our results indicate that: 1) the optoacoustic technique (unlike pure optical approaches and other noninvasive techniques) is capable of accurate peripheral venous oxygenation measurement; and 2) peripheral venous oxygenation is dependent on skin temperature and local hemodynamics. Moreover, we performed for the first time (to the best of our knowledge) a comparative study of optoacoustic arterial oximetry and a standard pulse oximeter in humans and demonstrated superior performance of the optoacoustic arterial oximeter, in particular at low blood flow.

  13. 论脉之生理特性%Discussion of physiological characteristic of blood vessel

    Institute of Scientific and Technical Information of China (English)

    刘玲

    2011-01-01

    The blood vessel has been named as extraordinary Fu-organ by traditional Chinese medicine. It's role is transporting the blood to nourishing the tissues and organs. As it hide between in the tissues,it lacks of the theories of physiological and pathological characteristics. So more blood vessel's diseases must be treated by adjusting blood. By modern technology,it has been proved that the blood vessel's disease is not only independent existence,but also the main pathological factor of the blood diseases. So preventing the blood vessel diseases,the main method is regulating and nourishing the blood vessel. This article thought that the physiological characteristics of the blood vessel are having unblocked's and nomal contraction or expansion's and solid wall's channel. It's also an organ of more Qi and blood. Besides the heart control,the healthy of blood vessel dependent on the unfold and smooth's liver Qi,and spleen Qi's manage.%传统中医学认为脉是奇恒之腑,具有输送血液濡养组织器官的作用.由于脉深藏于组织之间,故缺乏对脉生理、病理特点的论述,致使脉病多从血论治.现代科技手段证明脉病不仅独立存在,还是导致血病的主要病理因素.调脉、养脉是防治血病的重要环节.认为脉以柔顺畅达、舒缩有度、约束有节为生理特性,为多气多血组织,除心主血脉外,肝气的疏泄及脾气固摄都是脉保持健康、通畅的保证.

  14. 人工耳蜗植入术中客观检测技术的分析%Analysis of Objective Detecting Techniques during Cochlear Prosthesis Implantation

    Institute of Scientific and Technical Information of China (English)

    王铮; 谷佳; 韩涛; 田颖; 谢晓冬; 姜学钧

    2015-01-01

    目的 探讨人工耳蜗植入术中电诱发镫骨肌反射( elcetrically evoked stapedius responses, ESR)及神经反应遥测( neural response telemetry, NRT)的应用及临床意义. 方法 对22例行Nucleus 24 Contour型人工耳蜗植入者,在术中应用Cochlear公司提供的NRT 3. 0软件分别进行术中ESR和NRT检测,选取蜗底(1、3号电极)、蜗中(11、13号电极)及蜗顶( 20、22 号电极) ,分别检测对应的 ESR 阈值及 NRT 阈值. 结果 ESR 和 NRT 检出率分别为96. 21%(127/132)和95. 45%(126/132),ESR及NRT阈值由蜗底至蜗顶呈逐渐下降的趋势(P<0. 05),ESR与NRT阈值之间呈正相关(r=0. 53,P<0. 05). 结论 人工耳蜗植入术中应用ESR及NRT可以及时确认植入体植入情况,并且为术后调机提供客观的参考.%Objective To investigate the application and clinical significance of electrically evoked stapedius re-flex ( EESR) and neural response telemetry ( NRT) during cochlear prosthesis implantation. Methods A total of 22 pa-tients underwent Nucleus 24 Contour type of cochlear prosthesis implantation, and the values of intraoperative EESR and NRT were detected using NRT 3. 0 software provided by Cochlear corporation. The corresponding liminal values of EESR and NRT were respectively detected for basis cochleae ( number 1 and 3 electrodes) , within concha labyrinthi ( number 11 and 13 electrodes) and cupula cochleae ( number 20 and 22 electrodes) . Results The detection rates of EESR and NRT were 96. 21% (127/132) and 95. 45% (126/132), and the liminal values of EESR and NRT gradually decreased from the values of basis cochleae to cupula cochleae (P<0. 05), and the EESR liminal values were positively correlated with NRT liminal values (r=0. 53, P<0. 05). Conclusion The electrically evoked stapedius reflex and neural re-sponse telemetry in application of cochlear prosthesis implantation can quickly confirm the condition of implant button, and help cochlear programming after the operation.

  15. Comparison of cellular architecture, axonal growth, and blood vessel formation through cell-loaded polymer scaffolds in the transected rat spinal cord.

    Science.gov (United States)

    Madigan, Nicolas N; Chen, Bingkun K; Knight, Andrew M; Rooney, Gemma E; Sweeney, Eva; Kinnavane, Lisa; Yaszemski, Michael J; Dockery, Peter; O'Brien, Timothy; McMahon, Siobhan S; Windebank, Anthony J

    2014-11-01

    The use of multichannel polymer scaffolds in a complete spinal cord transection injury serves as a deconstructed model that allows for control of individual variables and direct observation of their effects on regeneration. In this study, scaffolds fabricated from positively charged oligo[poly(ethylene glycol)fumarate] (OPF(+)) hydrogel were implanted into rat spinal cords following T9 complete transection. OPF(+) scaffold channels were loaded with either syngeneic Schwann cells or mesenchymal stem cells derived from enhanced green fluorescent protein transgenic rats (eGFP-MSCs). Control scaffolds contained extracellular matrix only. The capacity of each scaffold type to influence the architecture of regenerated tissue after 4 weeks was examined by detailed immunohistochemistry and stereology. Astrocytosis was observed in a circumferential peripheral channel compartment. A structurally separate channel core contained scattered astrocytes, eGFP-MSCs, blood vessels, and regenerating axons. Cells double-staining with glial fibrillary acid protein (GFAP) and S-100 antibodies populated each scaffold type, demonstrating migration of an immature cell phenotype into the scaffold from the animal. eGFP-MSCs were distributed in close association with blood vessels. Axon regeneration was augmented by Schwann cell implantation, while eGFP-MSCs did not support axon growth. Methods of unbiased stereology provided physiologic estimates of blood vessel volume, length and surface area, mean vessel diameter, and cross-sectional area in each scaffold type. Schwann cell scaffolds had high numbers of small, densely packed vessels within the channels. eGFP-MSC scaffolds contained fewer, larger vessels. There was a positive linear correlation between axon counts and vessel length density, surface density, and volume fraction. Increased axon number also correlated with decreasing vessel diameter, implicating the importance of blood flow rate. Radial diffusion distances in vessels

  16. In vivo experiments and numerical investigations on nanocryosurgical freezing of target tissues with large blood vessels.

    Science.gov (United States)

    Sun, Zi-Qiao; Yang, Yang; Liu, Jing

    2012-02-01

    This study presented the first in vivo animal experiments of using nano-cryosurgical modality to completely freezing tumor tissues embedded with large blood vessels, which is a tough issue to tackle otherwise. Three-dimensional theoretical simulations were also performed on the complex freezing problems by considering flow and heat transfer of blood flow in large vessels. According to the experimental measurements and numerical predictions, injecting the nanoparticles with high thermal conductivity into the freezing target can significantly reduce the heating effect of blood vessel, shorten the freezing time, and enlarge the freezing range. Most importantly, the introduction of nanoparticles successfully overcomes the classical challenges in completely ablating the tumor region with large blood vessel and enhancing the freezing efficacy of cryosurgery. This investigation consolidates the practical and theoretical foundation for nano-cryosurgery which suggests a highly efficient freezing strategy for treating late stage tumor.

  17. Genetic analysis of blood vessel formation role of endothelial versus smooth muscle cells.

    Science.gov (United States)

    Carmeliet, P; Collen, D

    1997-11-01

    Formation of new blood vessels is vital during embryogenesis, essential for reproduction and wound healing during adulthood, and required to rescue tissue during ischemia. Neovascularization may, however, also contribute to the pathogenesis of several disorders, including tumorigenesis, diabetic vasculopathy, and chronic inflammation. Initially, blood vessels form as endothelium-lined channels by in situ differentiation of endothelial cells. Subsequently, they sprout and remodel into a highly organized and interconnected vascular network. During further maturation of the blood vessels, a sheet of primitive vascular smooth muscle cells surrounds the endothelium-lined channels, which controls endothelial cell function and provides structural support. Recent molecular analyses have identified candidate molecules that affect these processes. Their in vivo role has been further established by targeted gene manipulation in transgenic mice. This review highlights recent developments in the genetic analysis of blood vessel formation, as deduced from analysis of gene-inactivated mice. (Trends Cardiovasc Med 1997;7:271-281). © 1997, Elsevier Science Inc.

  18. Blood vessel growth blocker may treat AIDS-related Kaposi’s sarcoma

    Science.gov (United States)

    Patients with an AIDS-associated cancer, Kaposi's sarcoma (KS), showed improvement after receiving the combination of bevacizumab, a cancer drug that blocks the growth of new blood vessels, and highly active antiretroviral therapy (HAART).

  19. 21 CFR 878.3800 - External aesthetic restoration prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External aesthetic restoration prosthesis. 878... External aesthetic restoration prosthesis. (a) Identification. An external aesthetic restoration prosthesis... external prosthesis adhesive. The device is not intended to be implanted. (b) Classification. Class...

  20. A comparative evaluation of linear dimensional accuracy of the dies obtained using three conceptually different die systems in the fabrication of implant prosthesis: An in vitro study

    Directory of Open Access Journals (Sweden)

    Manawar Ahmad

    2014-01-01

    Purpose: The purpose of the study was to evaluate the linear dimensional accuracy between the implant master die and three conceptually different die systems such as Pindex system, Accu-trac precision die system, and Conventional brass dowel pin system. Materials and Methods: Thirty impressions of implant master die were made with polyether impression material. Ten experimental implant casts were fabricated for each of the three different die systems tested: Accu-trac precision die tray system, Pindex system, and conventional brass dowel pin system. The solid experimental casts were sectioned and then removed from the die system 30 times. Linear distances between all six possible distances were measured from one centre of the transfer coping to the other, using a co-ordinate measuring machine in millimeters up to accuracy of 0.5 microns. Data were tabulated and statistically analyzed by Binomial non parametric test using SPSS version 15. Results: Significant differences were found for distance A-B (P = 0.002, A-C ( P = 0.002, A-D (P value = 0.002, and B-D ( P = 0.021 in Conventional Dowel pin system however for Accu-trac precision die tray system, it was significant only for distance A-D (P = 0.002 but for Pindex system it was non-significant for all the distances measured. Conclusion: Within the limitations of this study, use of Pindex system is recommended when sectioned dies are needed for a multi implant retained prosthesis.

  1. The Primary Study of the Construction of Small Diameter Tissue-engineered Blood Vessel

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionToday, the blood vessel substitutes are in large demand for coronary and peripheral bypass procedures. Each year, more than 600,000 coronary artery bypass graft procedures are performed in the United States. There are some blood vessel substitutes including autografts, allografts and synthetic grafts that have been applied in vascular surgery in clinics. But their clinical implementations are prevented, especially for the <6mm in diameter grafts, because of their shortcomings such as inadequat...

  2. Pericyte coverage of abnormal blood vessels in myelofibrotic bone marrows

    DEFF Research Database (Denmark)

    Zetterberg, Eva; Vannucchi, Alessandro M; Migliaccio, Anna Rita

    2007-01-01

    BACKGROUND AND OBJECTIVES: Myelofibrotic bone marrow displays abnormal angiogenesis but the pathogenic mechanisms of this are poorly understood. Since pericyte abnormalities are described on solid tumor vessels we studied whether vessel morphology and pericyte coverage in bone marrow samples from...... patients with myelofibrosis differed from that in samples from controls. DESIGN AND METHODS: We assessed the microvascular density (MVD), vessel morphology and pericyte coverage in bone marrows from 19 myelofibrosis patients and nine controls. We also studied the same parameters in two mouse models...... of myelofibrosis, with genetic alterations affecting megakaryocyte differentiation (i.e. one model with low GATA-1 expression and the other with over-expression of thrombopoietin). RESULTS: In myelofibrotic marrows, MVD was 3.8-fold greater than in controls (pvessels displayed 5.9-fold larger mean...

  3. [The structure of the developing blood vessels of the neocortical anlage of the human embryo].

    Science.gov (United States)

    Korzhevskiĭ, D E; Omel'chenko, N V; Smirnov, E B; Petrova, E S

    2000-01-01

    Using light and electron microscopy the structure of blood vessels of neocortical anlage of human 7-12 embryos was studied. It was shown that at the early stage of formation of intraorgan vascular network the wall of blood vessels of ventricular zone successively differentiate, which is characterized by the appearance of second layer of cells (pericytes), accumulation of basement membrane components, widening of the zone of contacts between endotheliocytes and establishment of the contacts with bipolar cells of neocortex anlage. The morphological data obtained assist in comprehension of physiological aspects of formation of blood brain barrier and regulation of blood flow in human embryonal neocortex.

  4. Impact of Cold Ischemia on Mitochondrial Function in Porcine Hearts and Blood Vessels

    Science.gov (United States)

    Wiedemann, Dominik; Schachner, Thomas; Bonaros, Nikolaos; Dorn, Melissa; Andreas, Martin; Kocher, Alfred; Kuznetsov, Andrey V.

    2013-01-01

    The effects of cold storage using Custodiol® (Histidine-Tryptophan-Ketoglutarate, HTK) or isotonic saline solution on mitochondrial function in hearts (left and rights ventricles) and various blood vessels of pigs were investigated. Hearts, saphenous veins, internal-mammary-arteries and aortas of male landrace pigs were harvested and exposed to cold ischemia in either saline or Custodiol-HTK solution. Mitochondrial function was measured in situ in permeabilized fibers by high-resolution respirometry. Mitochondrial respiratory capacities (maximal respiration rates) were similar in the right and left ventricle in controls and after 14 h of cold storage were significantly better preserved in Custodiol-HTK than in saline solution. Mitochondrial respiration rates in various blood vessels including aorta, arteries and veins were less than 5% of myocardium rates. In contrast to the pig heart, in some blood vessels, like veins, mitochondrial function remained stable even after 24 h of cold ischemia. HTK-Custodiol protection of mitochondrial function after prolonged cold ischemia was observed in the myocardium but not in blood vessels. HTK-Custodiol solution thus offers significant protection of myocardial mitochondria against cold ischemic injury and can be used as efficient preservation solution in organ transplantation but probably has no benefit for blood vessels preservation. Analysis of mitochondrial function can be used as a valuable approach for the assessment of cold ischemic injury in various tissues including pig heart and various blood vessels. PMID:24213604

  5. Impact of Cold Ischemia on Mitochondrial Function in Porcine Hearts and Blood Vessels

    Directory of Open Access Journals (Sweden)

    Andrey V. Kuznetsov

    2013-11-01

    Full Text Available The effects of cold storage using Custodiol® (Histidine-Tryptophan-Ketoglutarate, HTK or isotonic saline solution on mitochondrial function in hearts (left and rights ventricles and various blood vessels of pigs were investigated. Hearts, saphenous veins, internal-mammary-arteries and aortas of male landrace pigs were harvested and exposed to cold ischemia in either saline or Custodiol-HTK solution. Mitochondrial function was measured in situ in permeabilized fibers by high-resolution respirometry. Mitochondrial respiratory capacities (maximal respiration rates were similar in the right and left ventricle in controls and after 14 h of cold storage were significantly better preserved in Custodiol-HTK than in saline solution. Mitochondrial respiration rates in various blood vessels including aorta, arteries and veins were less than 5% of myocardium rates. In contrast to the pig heart, in some blood vessels, like veins, mitochondrial function remained stable even after 24 h of cold ischemia. HTK-Custodiol protection of mitochondrial function after prolonged cold ischemia was observed in the myocardium but not in blood vessels. HTK-Custodiol solution thus offers significant protection of myocardial mitochondria against cold ischemic injury and can be used as efficient preservation solution in organ transplantation but probably has no benefit for blood vessels preservation. Analysis of mitochondrial function can be used as a valuable approach for the assessment of cold ischemic injury in various tissues including pig heart and various blood vessels.

  6. Differential Effects between Cigarette Total Particulate Matter and Cigarette Smoke Extract on Blood and Blood Vessel

    Science.gov (United States)

    Park, Jung-Min; Chang, Kyung-Hwa; Park, Kwang-Hoon; Choi, Seong-Jin; Lee, Kyuhong; Lee, Jin-Yong; Satoh, Masahiko; Song, Seong-Yu; Lee, Moo-Yeol

    2016-01-01

    The generation and collection of cigarette smoke (CS) is a prerequisite for any toxicology study on smoking, especially an in vitro CS exposure study. In this study, the effects on blood and vascular function were tested with two widely used CS preparations to compare the biological effects of CS with respect to the CS preparation used. CS was prepared in the form of total particulate matter (TPM), which is CS trapped in a Cambridge filter pad, and cigarette smoke extract (CSE), which is CS trapped in phosphate-buffered saline. TPM potentiated platelet reactivity to thrombin and thus increased aggregation at a concentration of 25~100 μg/mL, whereas 2.5~10% CSE decreased platelet aggregation by thrombin. Both TPM and CSE inhibited vascular contraction by phenylephrine at 50~100 μg/mL and 10%, respectively. TPM inhibited acetylcholine-induced vasorelaxation at 10~100 μg/mL, but CSE exhibited a minimal effect on relaxation at the concentration that affects vasoconstriction. Neither TPM nor CSE induced hemolysis of erythrocytes or influenced plasma coagulation, as assessed by prothrombin time (PT) and activated partial thromboplastin time (aPTT). Taken together, CS affects platelet activity and deteriorates vasomotor functions in vitro. However, the effect on blood and blood vessels may vary depending on the CS preparation. Therefore, the results of experiments conducted with CS preparations should be interpreted with caution.

  7. Implantable blood pressure sensor for analyzing elasticity in arteries

    Science.gov (United States)

    Franco-Ayala, Marco; Martínez-Piñón, Fernando; Reyes-Barranca, Alfredo; Sánchez de la Peña, Salvador; Álvarez-Chavez, José A.

    2009-03-01

    MEMS technology could be an option for the development of a pressure sensor which allows the monitoring of several electronic signals in humans. In this work, a comparison is made between the typical elasticity curves of several arteries in the human body and the elasticity obtained for MEMS silicon microstructures such as membranes and cantilevers employing Finite Element analysis tools. The purpose is to identify which types of microstructures are mechanically compatible with human arteries. The goal is to integrate a blood pressure sensor which can be implanted in proximity with an artery. The expected benefits for this type of sensor are mainly to reduce the problems associated with the use of bulk devices through the day and during several days. Such a sensor could give precise blood pressure readings in a continuous or periodic form, i.e. information that is especially important for some critical cases of hypertension patients.

  8. Analyses of thermal stress and fracture during cryopreservation of blood vessel

    Institute of Scientific and Technical Information of China (English)

    华泽钊; 徐红艳; 周国燕; 刘锦纷; 黄惠民; 丁文祥

    2001-01-01

    The occurrence of fractures in the vessel wall has been a major problem for human blood vessel cryopreservation. The large volumetric expansion of water during crystallization produces great inner stresses. To solve these complicated heat transfer and thermal stress problems, a model and an analytic method are presented in this paper, with which transient temperature field, the transient stress field inside the blood vessels during freezing can be calculated and analyzed, and the probable cracks or fractures can be predicted. The analytic results of sheep thoracic artery are consistent with the experimental observations of fractures.

  9. Clinical and angiographic outcome of elective stent implantation in small coronary vessels: an analysis of the BENESTENT trial.

    Science.gov (United States)

    Keane, D; Azar, A J; de Jaegere, P; Rutsch, W; de Bruyne, B; Legrand, V; Kiemeneij, F; de Feyter, P; van de Heuvel, P; Ozaki, Y; Morel, M A; Serruys, P W

    1996-12-01

    We examined the influence of vessel size using an intention-to-treat approach in 259 patients who underwent stent implantation and in 257 patients who underwent balloon angioplasty alone in the BENESTENT trial. In the stented population, smaller vessel size was associated with a higher stent:vessel ratio, a greater relative gain and a greater subsequent loss index, and a higher risk of adverse cardiac events. In the balloon angioplasty population small vessel size conveyed an increased requirement for revascularization but did not increase the risk of procedural failure or myocardial infarction during follow-up. Logistic regression indicated that decreasing vessel size (as a continous variable) was associated with an increasing risk of a cardiac event for both the stent and balloon angioplasty populations.

  10. Computational study of thermal effects of large blood vessels in human knee joint.

    Science.gov (United States)

    Xue, Xu; He, Zhi Zhu; Liu, Jing

    2013-01-01

    This paper is dedicated to present a comprehensive investigation on the thermal effects of large blood vessels of human knee joint during topical cooling and fomentation treatment. A three-dimensional (3D) finite element analysis by taking full use of the anatomical CAD model of human knee joint was developed to accurately simulate the treatment process. Based on the classical Pennes bio-heat transfer equation, the time evolution of knee joint's temperature distribution and heat flux from large blood vessels was obtained. In addition, we compared several influencing factors and obtained some key conclusions which cannot be easily acquired through clinical experiments. The results indicated that the thermal effects of large blood vessels could remarkably affect the temperature distribution of knee joint during treatment process. Fluctuations of blood flow velocity and metabolic heat production rate affect little on the thermal effects of large blood vessels. Changing the temperature of blood and regimes of treatment could effectively regulate this phenomenon, which is important for many physiological activities. These results provide a guideline to the basic and applied research for the thermally significant large blood vessels in the knee organism.

  11. 21 CFR 872.3960 - Mandibular condyle prosthesis.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw to... requirement for premarket approval for any mandibular condyle prosthesis intended to be implanted in the...

  12. Vascular bursts enhance permeability of tumour blood vessels and improve nanoparticle delivery

    Science.gov (United States)

    Matsumoto, Yu; Nichols, Joseph W.; Toh, Kazuko; Nomoto, Takahiro; Cabral, Horacio; Miura, Yutaka; Christie, R. James; Yamada, Naoki; Ogura, Tadayoshi; Kano, Mitsunobu R.; Matsumura, Yasuhiro; Nishiyama, Nobuhiro; Yamasoba, Tatsuya; Bae, You Han; Kataoka, Kazunori

    2016-06-01

    Enhanced permeability in tumours is thought to result from malformed vascular walls with leaky cell-to-cell junctions. This assertion is backed by studies using electron microscopy and polymer casts that show incomplete pericyte coverage of tumour vessels and the presence of intercellular gaps. However, this gives the impression that tumour permeability is static amid a chaotic tumour environment. Using intravital confocal laser scanning microscopy we show that the permeability of tumour blood vessels includes a dynamic phenomenon characterized by vascular bursts followed by brief vigorous outward flow of fluid (named ‘eruptions’) into the tumour interstitial space. We propose that ‘dynamic vents’ form transient openings and closings at these leaky blood vessels. These stochastic eruptions may explain the enhanced extravasation of nanoparticles from the tumour blood vessels, and offer insights into the underlying distribution patterns of an administered drug.

  13. Computational Fluid Dynamics Analysis of Pulsatile Blood Flow Behavior in Modelled Stenosed Vessels with Different Severities

    Directory of Open Access Journals (Sweden)

    Mohsen Mehrabi

    2012-01-01

    Full Text Available This study focuses on the behavior of blood flow in the stenosed vessels. Blood is modelled as an incompressible non-Newtonian fluid which is based on the power law viscosity model. A numerical technique based on the finite difference method is developed to simulate the blood flow taking into account the transient periodic behaviour of the blood flow in cardiac cycles. Also, pulsatile blood flow in the stenosed vessel is based on the Womersley model, and fluid flow in the lumen region is governed by the continuity equation and the Navier-Stokes equations. In this study, the stenosis shape is cosine by using Tu and Devil model. Comparing the results obtained from three stenosed vessels with 30%, 50%, and 75% area severity, we find that higher percent-area severity of stenosis leads to higher extrapressure jumps and higher blood speeds around the stenosis site. Also, we observe that the size of the stenosis in stenosed vessels does influence the blood flow. A little change on the cross-sectional value makes vast change on the blood flow rate. This simulation helps the people working in the field of physiological fluid dynamics as well as the medical practitioners.

  14. Characteristics of blood vessels forming “sausages-on-a-string” patterns during hypertension

    Science.gov (United States)

    Ravnsborg Beierholm, Ulrik; Christian Brings Jacobsen, Jens; Holstein-Rathlou, Niels-Henrik; Alstrøm, Preben

    2007-03-01

    A phenomenon of alternate constrictions and dilatations in blood vessels has been studied for over 50 years. Recently, a theory has been presented involving a Rayleigh type instability. We analyze the model in terms of the lengths of the deformations in relation to the wall thickness, blood pressure and stress. Analytical and numerical results obtained are consistent with experimental data.

  15. Lymphatic vessels growing apart from blood vessels in transplanted corneas after the blockade of vascular endothelial growth factor C

    Institute of Scientific and Technical Information of China (English)

    Ye Hui; Yan Hao; Zhong Lei; Wang Tao; Deng Juan; Ling Shi-qi

    2016-01-01

    BACKGROUND:Corneal lymphangiogenesis is beneficial to the transport of corneal antigenic materials, and accelerates the process of antigen presentation, thereby playing an important role in corneal immunity. However, due to the paral el outgrowth of corneal blood and lymphatic vessels in transplanted corneas, it is often difficult to accurately evaluate the role of corneal lymphatic vessels in allograft rejection. OBJECTIVE:To explore the development of corneal lymphangiogenesis and angiogenesis in transplanted rat corneas after the blockade of vascular endothelial growth factor C (VEGF-C). METHODS:130 rats used to establish corneal al ogenic transplantation models were equally randomized into two groups:the anti-VEGF-C group and the control group. VEGF-C was blocked in the anti-VEGF-C group by intraperitoneal injection of neutralizing monoclonal anti-VEGF-C antibody every other day for 2 consecutive weeks. Meanwhile, rats in control groups received intraperitoneal injections of saline. Corneal angiogenesis and lymphangiogenesis were characterized using whole mount immunofluorescence, and the immune rejection of the grafts was evaluated by scoring the rejection index (RI). In addition, the expression of VEGF-C was examined by real-time PCR. The relationship of corneal lymphangiogenesis and angiogenesis to RI in transplanted corneas was also characterized. RESULTS AND CONCLUSION:VEGF-C expression was markedly downregulated after VEGF-C blockade. Corneal lymphangiogenesis developed in parallel with corneal angiogenesis in the control group. While there was a mild reduction in blood vessel area (BVA) and a significant decrease in lymphatic vessel area (LVA) in the anti-VEGF-C group (P0.05). the graft survival time in the anti-VEGF-C group was significantly increased compared with that in the control group (P<0.05). Our results show that the outgrowth of lymphatic vessels is separated from that of blood vessels in transplanted corneas by blocking VEGF-C. The blockade

  16. Temporary Ectopic Implantation of a Single Finger Using a Perforator as a Feeding Vessel, and Subsequent Prefabricated Chimeric Flap Transplantation

    Science.gov (United States)

    Takumi, Yamamoto; Hisako, Hara; Yusuke, Yamamoto; Azusa, Oshima; Kazuki, Kikuchi; Harunosuke, Kato; Kumiko, Sata; Kentaro, Doi; Takeshi, Todokoro; Jun, Araki; Makoto, Mihara; Takuya, Higashino; Takuya, Iida; Isao, Koshima

    2012-01-01

    Objective: Ectopic implantation was first reported by Godina in 1986. We herein present 2 cases in which amputated fingers were salvaged and reconstructed by means of temporary ectopic implantation utilizing perforator anastomoses and chimeric flaps. Methods: Case 1. A 30-year-old man injured his right hand. All of the fingers were completely crushed with the exception of the little finger. We performed an ectopic implantation by using the superficial circumflex iliac artery perforator. Three months later, the little finger was transplanted with the superficial circumflex iliac artery perforator flap, vascularized nerve, and the 2nd metacarpal bone. Case 2. A 29-year-old man suffered a degloving injury of the index finger. The digital artery was anastomosed to deep inferior epigastric artery perforator. One month later, a deep inferior epigastric artery perforator flap containing the ectopically transplanted index finger was transplanted, but the index fingertip became pale and necrotized. After debridement, a hemipulp transplantation was performed. Results/Conclusions: As the diameter of perforators is similar to that of digital arteries, and perforators are capable of supplying large areas of tissue, they can be used as recipient vessels for ectopic implantation in finger salvage procedures. Another advantage of perforators as feeding vessels in ectopic implantation is the possibility of forming an ectopic chimera; the finger can be incorporated as a part of the chimeric reconstructive flap. With respect to these advantages, the perforator can be used as a feeder in an ectopic implantation of single finger. PMID:27648114

  17. Establishing the maxillary occlusal plane as a requisite for placement of an immediate implant-supported fixed prosthesis in the mandible: a case report

    Directory of Open Access Journals (Sweden)

    Milton Edson Miranda

    Full Text Available INTRODUCTION: In patients with Bruxism, the attrition can result in excessive occlusal wear that exceeds the compensatory mechanism and loss of occlusion vertical dimension occurs. OBJECTIVE: The purpose of this article is to show the importance of re-establishing an adequate occlusal plane for the non treated arch by means of a fixed acrylic overlay, compatible with the prosthetic treatment of the arch to be rehabilitated. An upper maxillary fixed acrylic overlay restored the patient’s occlusal plane in an appropriate vertical dimension of occlusion together with a fixed prosthesis in the mandible, supported by five dental implants. CONCLUSION: When there is severe wear due to dental attrition in one of the arches, it is important to re-establish the occlusal plane and compensation curves in conjunction with the prosthetic treatment of the arch to be rehabilitated.

  18. Study of fluid dynamics reveals direct communications between lymphatic vessels and venous blood vessels at lymph nodes of mice.

    Science.gov (United States)

    Takeda, Kazu; Mori, Shiro; Kodama, Tetsuya

    2017-02-22

    Cancer cells metastasize to lymph nodes, with distant metastasis resulting in poor prognosis. The role of lymph node metastasis (LNM) in the spread of cancer to distant organs remain incompletely characterized. The visualization of flow dynamics in the lymphatic and blood vessels of MXH10/Mo-lpr/lpr mice, which develop systemic swelling of lymph nodes up to 10mm in diameter, has revealed that lymph nodes have the potential to be a direct source of systemic metastasis. However, it is not known whether these fluid dynamics characteristics are universal phenomena present in other strains of laboratory mice. Here we show that the fluid dynamics observed in MXH10/Mo-lpr/lpr mice are the same as those observed in C57BL/6J, BALB/cAJcl and NOD/ShiJic-scidJcl mice. Furthermore, when fluorescent solution was injected into a tumor-bearing lymph node, the flow dynamics observed in the efferent lymphatic vessels and thoracoepigastric vein depended on the type of tumor cell. Our results indicate that fluid dynamics in the lymphatic and blood vessels of MXH10/Mo-lpr/lpr mice are generalized phenomena seen in conventional laboratory mice. We anticipate our results can facilitate studies of the progression of lymphatic metastasis to hematogenous metastasis via lymph nodes and the early diagnosis and treatment of LNM.

  19. Correlation between the coverage percentage of prosthesis and postoperative hidden blood loss in primary total knee arthroplasty

    Institute of Scientific and Technical Information of China (English)

    Gao Fuqiang; Guo Wanshou; Sun Wei; Li Zirong; Wang Weiguo; Wang Bailiang; Cheng Liming

    2014-01-01

    Background The aim of this study was to determine the relationship between prosthesis coverage and postoperative hidden blood loss (HBL) in primary total knee arthroplasty (TKA).Methods A total of 120 patients who had undergone unilateral TKA from August 2012 to May 2013 were retrospectively studied.The Gross formula was used to calculate the amount of HBL.Routine standard anteroposterior (AP) and lateral x-ray films of the knee joint were taken postoperatively and used to measure the percentages of coronal femoral and of coronal and sagittal tibial prosthetic coverage.Then Pearson's correlation analysis was performed to assess the correlations between the percentages of prosthetic coverage for each AP and lateral position and HBL on the first and third postoperative days.Results The volumes of HBL on the first and third postoperative days after TKA were (786.5±191.6) ml and (1 256.6±205.1) ml,respectively,and lateral x-ray film measurements of percentages of coronal femoral,tibial coronal,and sagittal prosthetic coverage were (87.9±2.5)%,(88.5±2.2)%,and (89.1±2.3)%,respectively.Pearson's correlation analysis showed statistically significant correlations between percentages of total knee prosthetic coverage for each AP and lateral position and volumes of HBL on the first and third postoperative days (P <0.05).Conclusions HBL after TKA correlates with degree of prosthetic coverage.To some extent,the size of the surfaces exposed by osteotomy determines the amount of HBL.Choice of the appropriate prosthesis can significantly reduce postoperative HBL.Designing individualized prostheses would be a worthwhile development in joint replacement surgery.

  20. CFD Application in Implantable Rotary Blood Pump Design and Validation

    Institute of Scientific and Technical Information of China (English)

    YI Qian

    2004-01-01

    Implantable rotary blood pump (IRBP) has been promoted to the stage of clinical trial. This paper introduces a unique IRBP without a shaft. Instead of using thrombogenic pivots or power-drawing magnetic suspension, impeller is supported hydrodynamically when rotating, by lubrication flows in the thin spaces between itself and the pump body. To this end, the flow is very difficult to be measured using usual laboratory equipments. Therefore, computational fluid dynamics (CFD) has been applied as an important tool in the IRBP design and its validation procedure. Several CFD results such as pump performance improvement, unsteady hydraulic dynamic analysis, biocapability prediction, validation and verification (V&V), and flow visualization have been performed.

  1. Classification of Implantable Rotary Blood Pump States With Class Noise.

    Science.gov (United States)

    Ooi, Hui-Lee; Seera, Manjeevan; Ng, Siew-Cheok; Lim, Chee Peng; Loo, Chu Kiong; Lovell, Nigel H; Redmond, Stephen J; Lim, Einly

    2016-05-01

    A medical case study related to implantable rotary blood pumps is examined. Five classifiers and two ensemble classifiers are applied to process the signals collected from the pumps for the identification of the aortic valve nonopening pump state. In addition to the noise-free datasets, up to 40% class noise has been added to the signals to evaluate the classification performance when mislabeling is present in the classifier training set. In order to ensure a reliable diagnostic model for the identification of the pump states, classifications performed with and without class noise are evaluated. The multilayer perceptron emerged as the best performing classifier for pump state detection due to its high accuracy as well as robustness against class noise.

  2. CFD Application in Implantable Rotary Blood Pump Design and Validation

    Institute of Scientific and Technical Information of China (English)

    YIQian

    2004-01-01

    Implantable rotary blood pump (IRBP) has been promoted to the stage of clinical trial. This paper introduces a unique IRBP without a.shaft. Instead of using thrombogenic pivots or power-drawing magnetic suspension, impeller is supported hydrodynamically when rotating, by lubrication flows in the thin spaces between itself and the pump body. To this end, the flow is very difficult to be measured using usual laboratory equipments. Therefore, computational fluid dynamics (CFD) has been applied as an important tool in the IRBP design and its validation procedure. Several CFD results such as pump performance improvement, unsteady hydraulic dynamic analysis, biocapability prediction, validation and verification (V&V), and flow visualization have been performed.

  3. Proliferation of CD8-positive T cells in blood vessels of rat renal allografts.

    Science.gov (United States)

    Grau, V; Fuchs-Moll, G; Wilker, S; Weimer, R; Padberg, W

    2011-09-01

    It is still disputed in which anatomical compartments of allograft recipients T-cells proliferate. After experimental renal transplantation, host monocytes and lymphocytes accumulate in the lumina of graft blood vessels. In this study, we test the hypothesis that T lymphocytes proliferate in the vascular bed of the graft. Kidneys were transplanted in the Dark Agouti to Lewis rat strain combination, an established experimental model for acute rejection. Isogeneic transplantation was performed as a control. Cells in the S-phase of mitosis were detected in situ three days posttransplantation by pulse-labeling with BrdU and by immunohistochemical detection of the proliferating cell nuclear antigen (PCNA). More than 20% of all T-cells in the lumina of allograft blood vessels incorporated BrdU and approximately 30% of them expressed PCNA. In the blood vessels of isografts as well as in other organs of allograft recipients, only few BrdU(+) cells were detected. A majority of the BrdU(+) cells in graft blood vessels expressed CD8. In conclusion, we demonstrate that CD8(+) T lymphocytes proliferate in the lumina of the blood vessels of renal allografts during the onset of acute rejection.

  4. Long-range enhancers modulate Foxf1 transcription in blood vessels of pulmonary vascular network.

    Science.gov (United States)

    Seo, Hyejin; Kim, Jinsun; Park, Gi-Hee; Kim, Yuri; Cho, Sung-Won

    2016-09-01

    Intimate crosstalk occurs between the pulmonary epithelium and the vascular network during lung development. The transcription factor forkhead box f1 (Foxf1) is expressed in the lung mesenchyme and plays an indispensable role in pulmonary angiogenesis. Sonic hedgehog (Shh), a signalling molecule, is expressed in lung epithelium and is required to establish proper angiogenesis. It has been suggested that Foxf1, a downstream target of the Shh signalling pathway, mediates interaction between angiogenesis and the epithelium in lung. However, there has been no clear evidence showing the mechanism how Foxf1 is regulated by Shh signalling pathway during lung development. In this study, we investigated the lung-specific enhancers of Foxf1 and the Gli binding on the enhancers. At first, we found three evolutionarily conserved Foxf1 enhancers, two of which were long-range enhancers. Of the long-range enhancers, one demonstrated tissue-specific activity in the proximal and distal pulmonary blood vessels, while the other one demonstrated activity only in distal blood vessels. At analogous positions in human, these long-range enhancers were included in a regulatory region that was reportedly repeatedly deleted in alveolar capillary dysplasia with misalignment of pulmonary vein patients, which indicates the importance of these enhancers in pulmonary blood vessel formation. We also determined that Gli increased the activity of one of these long-range enhancers, which was specific to distal blood vessel, suggesting that Shh regulates Foxf1 transcription in pulmonary distal blood vessel formation.

  5. Implantable axialflow blood pump for left ventricular support.

    Science.gov (United States)

    Untaroiu, Alexandrina; Wood, Houston G; Allaire, Paul E

    2008-01-01

    Artificial blood pumps, either ventricular assist devices (VADs) or total artificial hearts, are currently employed for bridge to recovery, bridge to transplant, and destination therapy situations. The clinical effectiveness of VADs has been demonstrated; however, all of the currently available pumps have a limited life because of either the damage they cause to blood or their limited mechanical design life. A magnetically suspended rotary blood pump offers the potential to meet the requirements of both extending design life and causing negligible blood damage due to superior hemodynamics. Therefore, over the last few years, efforts of an interdisciplinary research team at University of Virginia have been concentrated on the design and development of a fully implantable axial flow VAD with a magnetically levitated impeller (LEV-VAD). This paper details the second generation developmental prototype (LEV-VAD2 design configuration) and includes a complete CFD analysis of device performance. Based on encouraging results of the first design stage, including a good agreement between the CFD performance estimations and the experimental measurements, a second design phase was initiated in an attempt to enhance device flow performance and suspension system capabilities. Using iterative design optimization stages, the design of the impeller and the geometry of the stationary and rotating blades have been reevaluated. A thorough CFD analysis allowed for optimization of the blood flow path such that an optimal trade-off among the hydraulic performance, specific requirements of a blood pump, and manufacturing requirements has been achieved. Per the CFD results, the LEV-VAD2 produces 6 lpm and 100 mmHg at a rotational speed of 7,000 rpm. The pressure-flow performance predictions indicate the LEV-VAD2's ability to deliver adequate flow over physiologic pressures for rotational speeds varying from 5,000 to 8,000 rpm. The blood damage numerical predictions also demonstrate

  6. ANALYSIS OF OSCILLATORY BLOOD FLOW IN VARYING-AREA ELASTIC VESSEL

    Institute of Scientific and Technical Information of China (English)

    Gong Ke-qin; Sun Hui; Liu Zhao-rong

    2003-01-01

    In this paper, by solving the fundamental equations of periodically oscillatory blood flow, the distributions of pressure gradient and blood velocity in varying-area elastic vessel were obtained, and then the wall shear stress and its gradient were calculated. As an example, the pulsatile blood flow in human carotid was analyzed and the effects of vessel taper angle on the distribution of wall shear stress and its gradient were discussed in detail. Numercial results show that the wall shear stress will enlarge when the taper angle increases. Meantime, no matter whether the vessel is converging or diverging, with the increase of the absolute value of taper angle, the amplitude of wall shear stress gradient will enlarge significantly.

  7. Macrophage-Induced Blood Vessels Guide Schwann Cell-Mediated Regeneration of Peripheral Nerves.

    Science.gov (United States)

    Cattin, Anne-Laure; Burden, Jemima J; Van Emmenis, Lucie; Mackenzie, Francesca E; Hoving, Julian J A; Garcia Calavia, Noelia; Guo, Yanping; McLaughlin, Maeve; Rosenberg, Laura H; Quereda, Victor; Jamecna, Denisa; Napoli, Ilaria; Parrinello, Simona; Enver, Tariq; Ruhrberg, Christiana; Lloyd, Alison C

    2015-08-27

    The peripheral nervous system has remarkable regenerative capacities in that it can repair a fully cut nerve. This requires Schwann cells to migrate collectively to guide regrowing axons across a 'bridge' of new tissue, which forms to reconnect a severed nerve. Here we show that blood vessels direct the migrating cords of Schwann cells. This multicellular process is initiated by hypoxia, selectively sensed by macrophages within the bridge, which via VEGF-A secretion induce a polarized vasculature that relieves the hypoxia. Schwann cells then use the blood vessels as "tracks" to cross the bridge taking regrowing axons with them. Importantly, disrupting the organization of the newly formed blood vessels in vivo, either by inhibiting the angiogenic signal or by re-orienting them, compromises Schwann cell directionality resulting in defective nerve repair. This study provides important insights into how the choreography of multiple cell-types is required for the regeneration of an adult tissue.

  8. [Fracture of macroporous hydroxyapatite prosthesis].

    Science.gov (United States)

    Adetchessi, A T; Pech-Gourg, G; Metellus, P; Fuentes, S

    2012-12-01

    Different prosthesis implants are offered to perform a cranioplasty after a decompressive craniectomy when autologous bone graft cannot be used. The authors report the case of a 25-year-old man who benefited a unilateral decompressive craniectomy after a severe head trauma. Seven months later, a cranioplasty using custom macroporous hydroxyapatite prosthesis was performed. The postoperative course was marked by a generalized seizure leading to a traumatic head injury. The CT-scan showed a comminutive fracture of the prosthesis and an extradural hematoma. The patient underwent a removal of the fractured prosthesis and an evacuation of the extradural clot. The postoperative course was uneventful with a Glasgow outcome scale score at 5. A second cranioplasty using a polyether ether ketone (PEEK) implant was performed. Among cranioplasty prosthesis solutions, hydroxyapatite implants seem to have similar property to the bone. However, its weak mechanic resistance is an actual problem in patients susceptible to present generalized seizures with consecutive head impact. Hence, in patients with decompressive craniectomy who are exposed to potential brain injury, we favor the use of more resistant implant as PEEK prosthesis.

  9. Noninvasive pulsatile flow estimation for an implantable rotary blood pump.

    Science.gov (United States)

    Karantonis, Dean M; Cloherty, Shaun L; Mason, David G; Ayre, Peter J; Lovell, Nigel H

    2007-01-01

    A noninvasive approach to the task of pulsatile flow estimation in an implantable rotary blood pump (iRBP) has been proposed. Employing six fluid solutions representing a range of viscosities equivalent to 20-50% blood hematocrit (HCT), pulsatile flow data was acquired from an in vitro mock circulatory loop. The entire operating range of the pump was examined, including flows from -2 to 12 L/min. Taking the pump feedback signals of speed and power, together with the HCT level, as input parameters, several flow estimate models were developed via system identification methods. Three autoregressive with exogenous input (ARX) model structures were evaluated: structures I and II used the input parameters directly; structure II incorporated additional terms for HCT; and the third structure employed as input a non-pulsatile flow estimate equation. Optimal model orders were determined, and the associated models yielded minimum mean flow errors of 5.49% and 0.258 L/min for structure II, and 5.77% and 0.270 L/min for structure III, when validated on unseen data. The models developed in this study present a practical method of accurately estimating iRBP flow in a pulsatile environment.

  10. How to explore the effects of sex hormone on blood vessels

    Institute of Scientific and Technical Information of China (English)

    Sun Mei-li; Nie Min; Liu Bing; Du Zhi-jun; Ge Qin-sheng

    2004-01-01

    The risk of cardiovascular disease increases along with aging. There are increasing interests in researches on the protective effects of hormone replacement therapy (HRT)on cardiovascular system in postmenopausal women. In this article we will review how we have explored the evidence of different sex hormones on blood vessels since 1996. The results showed that low-dose HRT significantly protected cardiovascular system in postmenopausal women.However, the high-dose 17β-estradiol (E2), with or without progesterone (P) or testosterone (T), or any hormone alone, as their concentrations increase, may even inhibit the protective effects of low-dose HRT on blood vessels.

  11. Simulation of Blood Flow at Vessel Bifurcation by Lattice Boltzmann Method

    Science.gov (United States)

    Kang, Xiu-Ying; Liu, Da-He; Zhou, Jing; Jin, Yong-Juan

    2005-11-01

    The application of the lattice Boltzmann method to the large vessel bifurcation blood flow is investigated in a wide range of Reynolds numbers. The velocity, shear stress and pressure distributions at the bifurcation are presented in detail. The flow separation zones revealed with increase of Reynolds number are located in the areas of the daughter branches distal to the outer corners of the bifurcation where some deposition of particular blood components might occur to form arteriosclerosis. The results also demonstrate that the lattice Boltzmann method is adaptive to simulating the flow in larger vessels under a high Reynolds number.

  12. Effect of Rolling Massage on the Vortex Flow in Blood Vessels with Lattice Boltzmann Simulation

    Science.gov (United States)

    Yi, Hou Hui

    The rolling massage manipulation is a classic Chinese Medical Massage, which is a nature therapy in eliminating many diseases. Here, the effect of the rolling massage on the cavity flows in blood vessel under the rolling manipulation is studied by the lattice Boltzmann simulation. The simulation results show that the vortex flows are fully disturbed by the rolling massage. The flow behavior depends on the rolling velocity and the rolling depth. Rolling massage has a better effect on the flows in the cavity than that of the flows in a planar blood vessel. The result is helpful to understand the mechanism of the massage and develop the rolling techniques.

  13. Clinical observation of surgery for the implantation cyst after orbital prosthesis implantation%义眼台植入后植入性囊肿手术治疗临床观察

    Institute of Scientific and Technical Information of China (English)

    许路加; 刘德成

    2016-01-01

    Objective To observe the efficacy of surgery for the subconjuntival implantation cysts after the orbital prosthesis impantation.Methods Under local anesthesia and thc surgical microscope,the tissue around the cyst was lifted by microscopic forceys and the conjunctiva was cut horizontally to separate and fully expose the cysts.Then the cyst was removed.The separation of cysts should be careful to avoid the perforation of the capsule wall which might cause residual cyst recurrence.Results There were 32 eyes of 32 cases of epithelial implantation cyst and the cyst was nearly circular,oval or nodular,translucent and soft texture with intact capsule wall.The pathological diagnosis was dermoid cyst with serous capsule contents and keratinized tisue.There was no recurrence among the 32cases.The prosthetic eye was placed three months later and the eye symmetry was good.Conclusion Surgery is the only effective treatment for epithelial implantation cysts.The removal of epithelial implantation cysts after prosthesis implantation,was safe and reliable with less damage and no recurrence.%目的 观察义眼台植入术后结膜下上皮植入性囊肿手术治疗的效果.方法 局麻,于手术显微镜下,用显微镊将囊肿旁的组织提起,水平剪开结膜,分离囊肿,充分暴露后将其完整摘除,分离囊肿时应小心剥离避免穿破,以免囊壁残留引起囊肿复发.结果 32例(32眼)上皮植入性囊肿,囊肿呈近圆形、椭圆形或结节状,半透明,质地软,囊壁完整无破裂.病理诊断:皮样囊肿,囊内容物为浆液行,间有角化组织.32例术后均无复发,3个月安装义眼片,双眼对称,外观良好.结论 手术摘除是治疗上皮植入囊肿的唯一有效方法.显微镜下行活动义眼植入术后的结膜下上皮植入性囊肿摘除术,安全可靠,损伤小,无复发.

  14. Aesthetic effect of single tooth implant prosthesis in the aesthetic area%美学区单牙种植修复的美学效果探讨

    Institute of Scientific and Technical Information of China (English)

    朱启红; 杨新亮; 殷宪雷

    2013-01-01

    目的:探讨美学区单牙种植修复的美学效果。方法:26例美学区单牙种植采用引导骨再生术,正确的种植三维位点,临时冠诱导软组织成型及个性化全瓷基台全瓷冠修复等进行美学修复。采用完美美学效果,患者满意度VAS进行美学效果评价。结果:26例美学区单牙种植修复,12月后种植体的成功率为100%;完美美学效果7例,美学效果较满意19例,美学效果很差0例;患者满意度V A S最低6分,最高10分,平均值8.26分。结论:根据自身条件,综合采用引导骨再生术,正确的种植三维位点,临时冠诱导软组织成型及个性化全瓷基台全瓷冠等进行美学区单个种植义齿的修复能满足患者的美学要求。%Objective : The aim of this study was to investigate the aesthetic effect of single tooth implant prosthesis in the aesthetic area. Methods: 26 single tooth implants were aesthetical y repaired in the aesthetic area with guided bone regeneration, correct aesthetic repair three-dimensional planting sites, temporary crowns induced soft tissue forming, personalized ful porcelain crown restoration with ful porcelain base stations. The aesthetic effect was evaluated with perfect aesthetic effect and patient satisfaction VAS. Results: The success rate was 100% after 12 months of these 26 cases of single tooth implant prosthesis in the aesthetic area, among which 7 cases were of perfect aesthetic effect, 19 cases were satisfied with aesthetic effect and 0 case was very poor aesthetic effect. Evaluated with Patient satisfaction VAS, the result was minimum 6 points, maximum 10 points and the average of 8.26 points. Conclusion: According to their own conditions, comprehensive application with guided bone regeneration , correct aesthetic repair three-dimensional planting sites , temporary crowns induced soft tissue forming, personalized ful porcelain crown restoration with ful porcelain base stations to do

  15. Mouse lung contains endothelial progenitors with high capacity to form blood and lymphatic vessels

    Directory of Open Access Journals (Sweden)

    Barleon Bernhard

    2010-07-01

    Full Text Available Abstract Background Postnatal endothelial progenitor cells (EPCs have been successfully isolated from whole bone marrow, blood and the walls of conduit vessels. They can, therefore, be classified into circulating and resident progenitor cells. The differentiation capacity of resident lung endothelial progenitor cells from mouse has not been evaluated. Results In an attempt to isolate differentiated mature endothelial cells from mouse lung we found that the lung contains EPCs with a high vasculogenic capacity and capability of de novo vasculogenesis for blood and lymph vessels. Mouse lung microvascular endothelial cells (MLMVECs were isolated by selection of CD31+ cells. Whereas the majority of the CD31+ cells did not divide, some scattered cells started to proliferate giving rise to large colonies (> 3000 cells/colony. These highly dividing cells possess the capacity to integrate into various types of vessels including blood and lymph vessels unveiling the existence of local microvascular endothelial progenitor cells (LMEPCs in adult mouse lung. EPCs could be amplified > passage 30 and still expressed panendothelial markers as well as the progenitor cell antigens, but not antigens for immune cells and hematopoietic stem cells. A high percentage of these cells are also positive for Lyve1, Prox1, podoplanin and VEGFR-3 indicating that a considerabe fraction of the cells are committed to develop lymphatic endothelium. Clonogenic highly proliferating cells from limiting dilution assays were also bipotent. Combined in vitro and in vivo spheroid and matrigel assays revealed that these EPCs exhibit vasculogenic capacity by forming functional blood and lymph vessels. Conclusion The lung contains large numbers of EPCs that display commitment for both types of vessels, suggesting that lung blood and lymphatic endothelial cells are derived from a single progenitor cell.

  16. Contact-inhibited chemotaxis in de novo and sprouting blood-vessel growth.

    Directory of Open Access Journals (Sweden)

    Roeland M H Merks

    Full Text Available Blood vessels form either when dispersed endothelial cells (the cells lining the inner walls of fully formed blood vessels organize into a vessel network (vasculogenesis, or by sprouting or splitting of existing blood vessels (angiogenesis. Although they are closely related biologically, no current model explains both phenomena with a single biophysical mechanism. Most computational models describe sprouting at the level of the blood vessel, ignoring how cell behavior drives branch splitting during sprouting. We present a cell-based, Glazier-Graner-Hogeweg model (also called Cellular Potts Model simulation of the initial patterning before the vascular cords form lumens, based on plausible behaviors of endothelial cells. The endothelial cells secrete a chemoattractant, which attracts other endothelial cells. As in the classic Keller-Segel model, chemotaxis by itself causes cells to aggregate into isolated clusters. However, including experimentally observed VE-cadherin-mediated contact inhibition of chemotaxis in the simulation causes randomly distributed cells to organize into networks and cell aggregates to sprout, reproducing aspects of both de novo and sprouting blood-vessel growth. We discuss two branching instabilities responsible for our results. Cells at the surfaces of cell clusters attempting to migrate to the centers of the clusters produce a buckling instability. In a model variant that eliminates the surface-normal force, a dissipative mechanism drives sprouting, with the secreted chemical acting both as a chemoattractant and as an inhibitor of pseudopod extension. Both mechanisms would also apply if force transmission through the extracellular matrix rather than chemical signaling mediated cell-cell interactions. The branching instabilities responsible for our results, which result from contact inhibition of chemotaxis, are both generic developmental mechanisms and interesting examples of unusual patterning instabilities.

  17. Generalization of geometrical flux maximizing flow on Riemannian manifolds for improved volumetric blood vessel segmentation.

    Science.gov (United States)

    Gooya, Ali; Liao, Hongen; Sakuma, Ichiro

    2012-09-01

    Geometric flux maximizing flow (FLUX) is an active contour based method which evolves an initial surface to maximize the flux of a vector field on the surface. For blood vessel segmentation, the vector field is defined as the vectors specified by vascular edge strengths and orientations. Hence, the segmentation performance depends on the quality of the detected edge vector field. In this paper, we propose a new method for level set based segmentation of blood vessels by generalizing the FLUX on a Riemannian manifold (R-FLUX). We consider a 3D scalar image I(x) as a manifold embedded in the 4D space (x, I(x)) and compute the image metric by pullback from the 4D space, whose metric tensor depends on the vessel enhancing diffusion (VED) tensor. This allows us to devise a non-linear filter which both projects and normalizes the original image gradient vectors under the inverse of local VED tensors. The filtered gradient vectors pertaining to the vessels are less sensitive to the local image contrast and more coherent with the local vessel orientation. The method has been applied to both synthetic and real TOF MRA data sets. Comparisons are made with the FLUX and vesselsness response based segmentations, indicating that the R-FLUX outperforms both methods in terms of leakage minimization and thiner vessel delineation.

  18. Thermal reactions of blood vessels in vascular stroke and heatstroke.

    Science.gov (United States)

    Thulesius, Olav

    2006-01-01

    Research on the pathophysiology and treatment of brain damage with special focus on thermal vascular responses is the subject of this minireview. Interruption of cerebral blood supply by vascular obstruction, temporary cardiac arrest or hyperthermia causes a sudden attack of vascular stroke or heatstroke with serious consequences. It may not induce immediate cell death, but can precipitate a complex biochemical cascade leading to a delayed neuronal loss. When testing thermal vasomotor responses by stepwise cooling of isolated carotid arteries, a temperature-proportional dilatation was observed while heating induced the opposite response: a marked vasoconstriction. General hyperthermia with an increased oxygen demand combined with a reduction of blood supply therefore is a serious consequence. At the cellular level an important mechanism involving hyperthermia is the temperature-dependent regulation of K(+) channel tone of vascular smooth muscle. Further, their inhibition through temperature elevation causes vasoconstriction. In heatstroke, which can induce platelet aggregation and the release of the vasoconstrictor serotonin, arterial cooling attenuates this response. General hypothermia is induced to prevent or attenuate neurological damage in stroke. The procedure is not without serious side effects. Therefore, rapid institution of selective brain cooling has been considered in adults and in infants with postpartum encephalopathy.

  19. Quantification of mast cells and blood vessels in the skin of patients with cutaneous mucinosis.

    Science.gov (United States)

    Martins, Clarice; Nascimento, Adriana Paulino; Monte-Alto-Costa, Andréa; Alves, Maria de Fátima Scotelaro; Carneiro, Sueli Coelho; Porto, Luís Cristóvão de Moraes Sobrino

    2010-07-01

    Recent studies have suggested that mast cell numbers are increased in the skin of patients with cutaneous mucinosis and that these cells may have an important role in angiogenesis and production of mucin. Then, skin biopsies from 30 patients with cutaneous mucinosis (papular mucinosis, focal mucinosis, and mucinosis associated with lupus erythematosus) and from 10 healthy subjects were analyzed. Mast cells and blood vessels were immunolabeled with anti-tryptase and anti-CD34 antibodies, respectively, and then quantified stereologically. Counting was performed in papillary and reticular dermis. An increase in the number of mast cells was observed in the skin of patients with cutaneous mucinosis compared with the control group. Only minimal differences were observed in vessel stereology. There was no correlation between the increase in the number of mast cells and the number of blood vessels in the patients studied. There was no significant difference in the numbers of mast cells or blood vessels between the 3 subgroups of cutaneous mucinosis. Although many clinical forms of mucinosis have been described, neither mast cell number nor vessel distribution seems to distinguish the 3 different forms studied here.

  20. Implantation of the VentrAssist Implantable Rotary Blood Pump in sheep.

    Science.gov (United States)

    James, Natalie L; van der Meer, Anita L; Edwards, Glenn A; Snelling, Samuel R; Begg, John D; Esmore, Donald S; Woodard, John C

    2003-01-01

    The VentrAssist Implantable Rotary Blood Pump (IRBP) is a hydrodynamically suspended, electromagnetically driven, centrifugal blood pump that provides continuous flow of up to 10 L/min at 3,000 rpm. In vivo studies in sheep were conducted to assess system design and performance. Surgery involved thoracotomy with subdiaphragmatic pump placement. Cannulae were transdiaphragmatic, with inflow in the left ventricular apex and outflow anastomosed to the descending aorta. Animals had no anticoagulation or antiplatelet therapy after surgery and no prophylactic antibiotics after recovery. Twelve sheep were supported for 622 pump days. Estimated pump flow ranged from 1 to 5.5 L/min at 1,800 to 2,000 rpm using 2.5 to 4.5 W. There was no clinical evidence of hemolysis or cardiovascular, renal, or hepatic dysfunction. Adverse outcomes included kinking/disconnection of the outflow cannula caused by the graft bend relief (n = 4), which was addressed through cannula redesign. Pump electrical malfunction (n = 4), caused by a silicone potting compound, was corrected using a neutral curing potting material. Surgical/husbandry issues (n = 2) also were addressed. The VentrAssist IRBP provides high flow at low rotational speed and power consumption. Further trials are in progress in advance of in vivo studies of the safety and efficacy of the final system.

  1. Effect of type of luting agents on stress distribution in the bone surrounding implants supporting a three-unit fixed dental prosthesis: 3D finite element analysis

    Science.gov (United States)

    Ghasemi, Ehsan; Abedian, Alireza; Iranmanesh, Pedram; Khazaei, Saber

    2015-01-01

    Background: Osseointegration of dental implants is influenced by many biomechanical factors that may be related to stress distribution. The aim of this study was to evaluate the effect of type of luting agent on stress distribution in the bone surrounding implants, which support a three-unit fixed dental prosthesis (FDP) using finite element (FE) analysis. Materials and Methods: A 3D FE model of a three-unit FDP was designed replacing the maxillary first molar with maxillary second premolar and second molar as the abutments using CATIA V5R18 software and analyzed with ABAQUS/CAE 6.6 version. The model was consisted of 465108 nodes and 86296 elements and the luting agent thickness was considered 25 μm. Three load conditions were applied on eight points in each functional cusp in horizontal (57.0 N), vertical (200.0 N) and oblique (400.0 N, θ = 120°) directions. Five different luting agents were evaluated. All materials were assumed to be linear elastic, homogeneous, time independent and isotropic. Results: For all luting agent types, the stress distribution pattern in the cortical bone, connectors, implant and abutment regions was almost uniform among the three loads. Furthermore, the maximum von Mises stress of the cortical bone was at the palatal side of second premolar. Likewise, the maximum von Mises stress in the connector region was in the top and bottom of this part. Conclusion: Luting agents transfer the load to cortical bone and different types of luting agents do not affect the pattern of load transfer. PMID:25709676

  2. Characterization of Imidazoline Receptors in Blood Vessels for the Development of Antihypertensive Agents

    OpenAIRE

    Mei-Fen Chen; Jo-Ting Tsai; Li-Jen Chen; Tung-Pi Wu; Jia-Jang Yang; Li-Te Yin; Yu-lin Yang; Tai-An Chiang; Han-Lin Lu; Ming-Chang Wu

    2014-01-01

    It has been indicated that activation of peripheral imidazoline I2-receptor (I-2R) may reduce the blood pressure in spontaneously hypertensive rats (SHRs). Also, guanidinium derivatives show the ability to activate imidazoline receptors. Thus, it is of special interest to characterize the I-2R using guanidinium derivatives in blood vessels for development of antihypertensive agent(s). Six guanidinium derivatives including agmatine, amiloride, aminoguanidine, allantoin, canavanine, and metform...

  3. Blood vessels and desmin control the positioning of nuclei in skeletal muscle fibers

    DEFF Research Database (Denmark)

    Ralston, E; Lu, Z; Biscocho, N

    2006-01-01

    . Here we show that the nuclei are preferentially localized near blood vessels (BV), particularly in slow-twitch, oxidative fibers. Thus, in rat soleus muscle fibers, 81% of the nuclei appear next to BV. Lack of desmin markedly perturbs the distribution of nuclei along the fibers but does not prevent...

  4. Cerebral blood flow in small vessel disease : A systematic review and meta-analysis

    NARCIS (Netherlands)

    Shi, Yulu; Thrippleton, Michael J; Makin, Stephen D; Marshall, Ian; Geerlings, Mirjam I; de Craen, Anton Jm; van Buchem, Mark A; Wardlaw, Joanna M

    2016-01-01

    White matter hyperintensities are frequent on neuroimaging of older people and are a key feature of cerebral small vessel disease. They are commonly attributed to chronic hypoperfusion, although whether low cerebral blood flow is cause or effect is unclear. We systematically reviewed studies that as

  5. Measurement of streaming potentials of mammalian blood vessels, aorta and vena cava, in vivo.

    Science.gov (United States)

    Sawyer, P N; Himmelfarb, E; Lustrin, I; Ziskind, H

    1966-09-01

    Attempts to measure streaming potentials in large rabbit blood vessels in vivo have been carried out. Streaming potentials, V(89), were measured by the introduction of microelectrodes through the wall of the blood vessel at separations greater than 1 cm. The outputs from these electrodes fed through calomel cells were amplified and recorded directly by using an Electronics for Medicine photorecorder (White Plains, N. Y.). "Effective streaming currents" were determined by running the output through a low impedence galvanometer while simultaneously measuring the resistance of the circuit V(8) were, therefore, calculated from two measurements and compared. Flow through vessels studied was measured using two different electromagnetic flowmeters. The results indicate that V(8) present in both aorta and vena cava are of the order of 5 to 10 mv. By using the Helmholtz-Smoluchowski equation into which flow was reintegrated, the numbers yield zeta potentials approximating 0.1 to 0.4 v in both aorta and vena cava. This number approaches the apparent upper limit for zeta (actually "interfacial potentials") potentials in biological systems. The measured "i.f." potential is considered as the interreaction of several physical and metabolic factors operating at the blood intimal interface. The polarity of the potential suggests that the interface is negative with respect to the blood flowing through the vessel. Interfacial potential and related V(8) are discussed in terms of their possible importance as a mechanism for maintaining vascular homeostasis in the living animal.

  6. Photoacoustic imaging of blood vessels with a double-ring sensor featuring a narrow angular aperture

    NARCIS (Netherlands)

    Kolkman, Roy G.M.; Hondebrink, Erwin; Steenbergen, Wiendelt; Leeuwen, van Ton G.; Mul, de Frits F.M.

    2004-01-01

    A photoacoustic double-ring sensor, featuring a narrow angular aperture, is developed for laser-induced photoacoustic imaging of blood vessels. An integrated optical fiber enables reflection-mode detection of ultrasonic waves. By using the cross-correlation between the signals detected by the two ri

  7. In situ tissue engineering of functional small-diameter blood vessels by host circulating cells only

    NARCIS (Netherlands)

    Talacua, Hanna; Smits, Anthal I P M; Muylaert, Dimitri E P; Van Rijswijk, Jan Willem; Vink, Aryan; Verhaar, Marianne C.; Driessen-Mol, Anita; Van Herwerden, Lex A.; Bouten, Carlijn V C; Kluin, Jolanda; Baaijens, Frank P T

    2015-01-01

    Inflammation is a natural phase of the wound healing response, which can be harnessed for the in situ tissue engineering of small-diameter blood vessels using instructive, bioresorbable synthetic grafts. This process is dependent on colonization of the graft by host circulating cells and subsequent

  8. A silver nanocomposite biomaterial for blood-contacting implants.

    Science.gov (United States)

    de Mel, Achala; Chaloupka, Karla; Malam, Yogeshkumar; Darbyshire, Arnold; Cousins, Brian; Seifalian, Alexander M

    2012-09-01

    Cardiovascular implants must resist infection and thrombosis. A nanocomposite polymeric material [polyhedral-oligomeric-silsesquioxane-poly(carbonate-urea)urethane; POSS-PCU] demonstrates ideal properties for cardiovascular applications. Silver nanoparticles or nanosilver (NS) are recognized for efficient antibacterial properties. This study aims to determine the influence of NS integrated POSS-PCU on thrombogenicity. Silver nitrate was reduced with dimethylformamide and stabilized by the inclusion of fumed silica nanoparticles to prevent aggregation of NS and were incorporated into POSS-PCU to form a range of POSS-PCU-NS concentrations (by weight); 0.20% (NS16), 0.40% (NS32), 0.75% (NS64), and 1.50% (NS128). Surface wettability was determined with sessile-drop water contact angles. Platelets were introduced onto test samples and Alamar Blue (AB), mitochondrial-activity assay, quantified the degree of platelet adhesion whilst platelet-factor-4 (PF4) ELISA quantified the degree of platelet activation. Thromboelastography (TEG) determined the profiles of whole blood kinetics while hemolysis assay demonstrated the degree of blood compatibility. Increasing levels of NS induced greater hydrophilicity. A concentration dependant decrease in platelet adhesion and activation was observed with AB and PF4 readings, respectively. TEG demonstrated that the antithrombogenic properties of POSS-PCU were retained with POSS-PCU-NS16, and enhanced with POSS-PCU-NS32, but was reduced with POSS-PCU-NS64 and POSS-PCU-NS128. POSS-PCU-NS64 and POSS-PCU-NS128 demonstrated a hemolytic tendency, but no hemolysis was observed with POSS-PCU-NS16 and POSS-PCU-NS32. Overall, POSS-PCU-NS32 rendered potent antithrombogenic properties.

  9. [Shift the skin paddle in an additional incision improves the result: Study of a series of 82 breast reconstructions by latissimus dorsi flap and prosthesis implantation at 10 years].

    Science.gov (United States)

    Chiriac, S; Dissaux, C; Bruant-Rodier, C; Djerada, Z; Bodin, F; François, C

    2016-11-17

    The position of the skin paddle on the breast area is a fundamental element for the breast reconstructions by latissimus dorsi flap and prosthesis implantation. Should, as Millard advocated, to recreate the initial defect and include it in the mastectomy scar or is it better in an additional incision as have others authors. This study compares the long-term morphological results of these two attitudes, with or without additional incision.

  10. Effect of mitral valve prosthesis design and orientation on intraventricular flow and blood stasis

    Science.gov (United States)

    May-Newman, Karen; Campos, J.; Montes, R.; Ramesh, V.; Moon, J.; Reider, C.; Martinez-Legazpi, P.; Bermejo, J.; Rossini, Lorenzo; Del Alamo, Juan C.

    2016-11-01

    Abnormal blood flow patterns are linked with thromboembolism (TE), especially in the presence of medical devices such as mitral valve prostheses (MVP). We performed PIV on a customized silicone left ventricle (LV) in a mock circulatory loop. We measured the velocity field in the long-axis midplane for 3 different MVP: a porcine bioprosthesis (BP), a tilting disk valve in two orientations: towards the LV lateral (TD-L) or the anterior wall (TD-A), and a bileaflet valve with anti-anatomical orientation (BL). Diastolic LV vortices were tracked and related to measures of blood stasis based on LV residence time. The BP and the TD-L produced flow patterns similar to those measured in patients. The TD-A showed a complete reversal of diastolic vortices. The BL design had increased apical blood stasis, which may lead to increased TE risk.

  11. Automated characterization of blood vessels as arteries and veins in retinal images.

    Science.gov (United States)

    Mirsharif, Qazaleh; Tajeripour, Farshad; Pourreza, Hamidreza

    2013-01-01

    In recent years researchers have found that alternations in arterial or venular tree of the retinal vasculature are associated with several public health problems such as diabetic retinopathy which is also the leading cause of blindness in the world. A prerequisite for automated assessment of subtle changes in arteries and veins, is to accurately separate those vessels from each other. This is a difficult task due to high similarity between arteries and veins in addition to variation of color and non-uniform illumination inter and intra retinal images. In this paper a novel structural and automated method is presented for artery/vein classification of blood vessels in retinal images. The proposed method consists of three main steps. In the first step, several image enhancement techniques are employed to improve the images. Then a specific feature extraction process is applied to separate major arteries from veins. Indeed, vessels are divided to smaller segments and feature extraction and vessel classification are applied to each small vessel segment instead of each vessel point. Finally, a post processing step is added to improve the results obtained from the previous step using structural characteristics of the retinal vascular network. In the last stage, vessel features at intersection and bifurcation points are processed for detection of arterial and venular sub trees. Ultimately vessel labels are revised by publishing the dominant label through each identified connected tree of arteries or veins. Evaluation of the proposed approach against two different datasets of retinal images including DRIVE database demonstrates the good performance and robustness of the method. The proposed method may be used for determination of arteriolar to venular diameter ratio in retinal images. Also the proposed method potentially allows for further investigation of labels of thinner arteries and veins which might be found by tracing them back to the major vessels.

  12. [Three-dimensional analysis of the foot following implantation of a HINTEGRA ankle prosthesis: evaluation with the Heidelberg foot model].

    Science.gov (United States)

    Müller, S; Wolf, S; Döderlein, L

    2006-05-01

    Detailed foot kinematics after total ankle replacement has not yet been investigated. In this study 11 patients with unilateral Hintegra ankle prosthesis were analysed with the Heidelberg Foot Model. This model measures the kinematics of the fore-, mid- and hindfoot in three clinical planes. Moreover, the kinetics of the hip, knee and ankle was captured. A diminished ROM was found in all foot segments investigated. The timing of the kinematics between sound and involved side appeared similar. A limitation in the hindfoot mobility, as experienced after ankle arthrodesis, was not observed. However, a careful hindfoot alignment is essential for optimal foot function, and previous malalignments should be corrected. Concerning the kinetics, the replaced ankle showed a decreased power generation compensated by an increase in power in the ipsilateral knee. For a more detailed evaluation, further studies are required which include pre- and postoperative data and also take into account different types of prostheses.

  13. Measurements of Dynamic Viscoelasticity of Poly (vinyl alcohol) Hydrogel for the Development of Blood Vessel Biomodeling

    Science.gov (United States)

    Kosukegawa, Hiroyuki; Mamada, Keisuke; Kuroki, Kanju; Liu, Lei; Inoue, Kosuke; Hayase, Toshiyuki; Ohta, Makoto

    In vitro blood vessel biomodeling with realistic mechanical properties and geometrical structures is helpful for training in surgical procedures, especial those used in endovascular treatment. Poly (vinyl alcohol) hydrogel (PVA-H), which is made of Poly (vinyl alcohol) (PVA) and water, may be useful as a material for blood vessel biomodeling due to its low surface friction resistance and good transparency. In order to simulate the mechanical properties of blood vessels, measurements of mechanical properties of PVA-H were carried out with a dynamic mechanical analyzer, and the storage modulus (G’) and loss modulus (G”) of PVA-H were obtained. PVA-Hs were prepared by the low-temperature crystallization method. They were made of PVA with various concentrations (C) and degrees of polymerization (DP), and made by blending two kinds of PVA having different DP or saponification values (SV). The G’ and G” of PVA-H increased, as the C or DP of PVA increased, or as the proportion of PVA with higher DP or SV increased. These results indicate that it is possible to obtain PVA-H with desirable dynamic viscoelasticity. Furthermore, it is suggested that PVA-H is stable in the temperature range of 0°C to 40°C, indicating that biomodeling made of PVA-H should be available at 37°C, the physiological temperature. The dynamic viscoelasticity of PVA-H obtained was similar to that of the dog blood vessel measured in previous reports. In conclusion, PVA-H is suggested to be useful as a material of blood vessel biomodeling.

  14. Hybrid PIV-PTV technique for measuring blood flow in rat mesenteric vessels.

    Science.gov (United States)

    Ha, Hojin; Nam, Kweon-Ho; Lee, Sang Joon

    2012-11-01

    The micro-particle tracking velocimetry (μ-PTV) technique is used to obtain the velocity fields of blood flow in the microvasculature under in vivo conditions because it can provide the blood velocity distribution in microvessels with high spatial resolution. The in vivo μ-PTV technique usually requires a few to tens of seconds to obtain a whole velocity profile across the vessel diameter because of the limited number density of tracer particles under in vivo conditions. Thus, the μ-PTV technique alone is limited in measuring unsteady blood flows that fluctuate irregularly due to the heart beating and muscle movement in surrounding tissues. In this study, a new hybrid PIV-PTV technique was established by combining PTV and particle image velocimetry (PIV) techniques to resolve the drawbacks of the μ-PTV method in measuring blood flow in microvessels under in vivo conditions. Images of red blood cells (RBCs) and fluorescent particles in rat mesenteric vessels were obtained simultaneously. Temporal variations of the centerline blood velocity were monitored using a fast Fourier transform-based cross-correlation PIV method. The fluorescence particle images were analyzed using the μ-PTV technique to extract the spatial distribution of the velocity vectors. Data from the μ-PTV and PIV methods were combined to obtain a better estimate of the velocity profile in actual blood flow. This technique will be useful in investigating hemodynamics in microcirculation by measuring unsteady irregular blood flows more accurately.

  15. Effect of the number of abutments on biomechanics of Branemark prosthesis with straight and tilted distal implants

    Directory of Open Access Journals (Sweden)

    Marcos Michelon Naconecy

    2010-04-01

    Full Text Available OBJECTIVE: This study aimed to evaluate the bending moments, and compressive and tensile forces in implant-supported prostheses with three, four or five abutments. MATERIAL AND METHODS: Ten Pd-Ag frameworks were tested over two master models with: 1 parallel vertical implants, and 2 tilted distal implants. Strain gauges were fixed on the abutments of each master model to measure the deformation when a static load of 50 N was applied on the cantilever (15 mm. The deformation values were measured when the metallic frameworks were tested over three, four or five abutments, and transformed into force and bending moment values. Data were analyzed by ANOVA and Tukey's test for multiple comparisons at 5% level of significance. RESULTS: Abutment #1 (adjacent to the cantilever had the highest values of force and sagittal bending moment for all tests with three, four or five abutments. Independently from the number of abutments, axial force in abutment #1 was higher in the vertical model than in the tilted model. Total moment was higher with three abutments than with four or five abutments. Independently from the inclination of implants, the mean force with four or five abutments was lower than that with three abutments. CONCLUSION: The results suggest that in the set-ups with four or five abutments tilted distal implants reduced axial force and did not increase bending moments.

  16. Optics based signal processing methods for intraoperative blood vessel detection and quantification in real time (Conference Presentation)

    Science.gov (United States)

    Chaturvedi, Amal; Shukair, Shetha A.; Le Rolland, Paul; Vijayvergia, Mayank; Subramanian, Hariharan; Gunn, Jonathan W.

    2016-03-01

    Minimally invasive operations require surgeons to make difficult cuts to blood vessels and other tissues with impaired tactile and visual feedback. This leads to inadvertent cuts to blood vessels hidden beneath tissue, causing serious health risks to patients and a non-reimbursable financial burden to hospitals. Intraoperative imaging technologies have been developed, but these expensive systems can be cumbersome and provide only a high-level view of blood vessel networks. In this research, we propose a lean reflectance-based system, comprised of a dual wavelength LED, photodiode, and novel signal processing algorithms for rapid vessel characterization. Since this system takes advantage of the inherent pulsatile light absorption characteristics of blood vessels, no contrast agent is required for its ability to detect the presence of a blood vessel buried deep inside any tissue type (up to a cm) in real time. Once a vessel is detected, the system is able to estimate the distance of the vessel from the probe and the diameter size of the vessel (with a resolution of ~2mm), as well as delineate the type of tissue surrounding the vessel. The system is low-cost, functions in real-time, and could be mounted on already existing surgical tools, such as Kittner dissectors or laparoscopic suction irrigation cannulae. Having been successfully validated ex vivo, this technology will next be tested in a live porcine study and eventually in clinical trials.

  17. Peristaltic Pumping of Blood in micro-vessels of Non-uniform Cross-section

    CERN Document Server

    Misra, J C

    2010-01-01

    The paper is devoted to a study of the peristaltic motion of blood in the micro-circulatory system. The vessel is considered of non-uniform cross-section. The progressive peristaltic waves are taken to be of sinusoidal nature. The Reynolds number is considered to be small. Blood is considered to be a Herschel-Bulkley fluid. Of particular concern here is to investigate the effects of amplitude ratio, mean pressure gradient, yield stress and the power law index on the velocity distribution, streamline pattern and wall shear stress. Basing upon the study, extensive numerical calculations has been made. The study reveals that peristaltic pumping as well as velocity and wall shear stress are appreciably affected due to the non-uniform geometry of blood vessels. They are also highly sensitive to the magnitude of the amplitude of the amplitude ratio and the value of the fluid index.

  18. Material-mediated proangiogenic factor release pattern modulates quality of regenerated blood vessels.

    Science.gov (United States)

    Rich, Max H; Lee, Min Kyung; Baek, Kwanghyun; Jeong, Jae Hyun; Kim, Dong Hyun; Millet, Larry J; Bashir, Rashid; Kong, Hyunjoon

    2014-12-28

    Hydrogels designed to sustainably release bioactive molecules are extensively used to enhance tissue repair and regenerative therapies. Along this line, numerous efforts are made to control the molecular release rate and amount. In contrast, few efforts are made to control the molecular release pattern, and, subsequently, modulate the spatial organization of newly forming tissues, including blood vessels. Therefore, using a hydrogel printed to release vascular endothelial growth factor (VEGF) into a pre-defined pattern, this study demonstrates that spatial distribution of VEGF is important in guiding growth direction of new blood vessels, and also in retaining the structural integrity of pre-existing vasculature. Guided by a computational model, we fabricated a patch composed of micro-sized VEGF-releasing poly(ethylene glycol) diacrylate (PEGDA) hydrogel cylinders using an ink-jet printer. Interestingly, hydrogel printed with computationally optimized spacing created anisotropically aligned vasculature exclusively when the printed gel pattern was placed parallel to pre-existing blood vessels. In contrast, vascular sprouting from placing the printed gel pattern perpendicular to pre-existing vessels resulted in deformation and structural disintegration of the original vasculature. We envision that this study will be useful to better understand angiogenesis-modulated neovascularization and further improve the treatment quality for various wounds and tissue defects.

  19. Mechanical properties of biodegradable small-diameter chitosan artificial vascular prosthesis.

    Science.gov (United States)

    Kong, Xiaoying; Han, Baoqin; Wang, Haixia; Li, Hui; Xu, Wenhua; Liu, Wanshun

    2012-08-01

    Initial clinical feasibility with the small-diameter chitosan artificial vascular prosthesis has been reported previously. Here, we present the results of mechanical properties of artificial vascular prosthesis with 2, 3, and 4 mm inner diameter (ID) and compare some of the properties with the native blood vessel of dog femoral artery. Thickness wall measurement demonstrated the average wall thickness of the artificial vascular prosthesis with 2, 3, and 4 mm ID and the native blood vessel of the dog femoral artery with 3 mm ID were 0.54 ± 0.022 mm, 0.71 ± 0.032 mm, 0.79 ± 0.026 mm, and 0.67 ± 0.22 mm (n = 20). Water absorption rate of 226.02% ± 8.17%, 216.13% ± 4.86%, and 205.69% ± 4.34% were obtained from 2-, 3-, and 4-mm-diameter artificial vascular prosthesis (n = 12), respectively. Water osmotic pressure of the 2-, 3-, and 4-mm-diameter artificial vascular prosthesis was 39.25 ± 3.35 mmHg, 34.2 ± 4.54 mmHg, and 28.00 ± 2.72 mmHg (n = 20), respectively. Water osmotic amount of the 2-, 3-, and 4-cm-diameter artificial vascular prosthesis (n = 20) was 4.90 ± 0.47 mL/(min cm(2) ), 5.51 ± 0.21 mL/(min cm(2) ), and 6.24 ± 0.71 mL/(min cm(2) ), respectively. The ruptured stretching rate of the artificial vascular prosthesis (n = 20) with 2, 3, and 4 mm ID and the native blood vessel was 1.59% ± 0.14%, 1.99% ± 0.24%, 2.52% ± 0.21%, and 32.16% ± 2.15%, respectively. The longitudinal tensile strength of the artificial vascular prosthesis (n = 20) with 2, 3, and 4 mm ID and the native blood vessel was 8.58 ± 1.98 N, 19.75 ± 4.07 N, 22.92 ± 3.85 N, and 18.76 ± 2.05 N, respectively. The suture retention of the artificial vascular prosthesis (n = 20) with 2, 3, and 4 mm ID and the native blood vessel in dry condition is 5.80 ± 0.51 N, 7.01 ± 0.32 N, 8.49 ± 0.56 N, and 7.92 ± 0.39 N, respectively. The suture retention of the artificial vascular prosthesis (n = 20) with 2, 3, and 4 mm ID in wet condition is 3.87 ± 0.43 N, 4.73 ± 0.37 N, 5.63 ± 0

  20. Simulation of Blood Flow at Vessel Bifurcation by Lattice Boltzmann Method

    Institute of Scientific and Technical Information of China (English)

    KANG Xiu-Ying; LIU Da-He; ZHOU Jing; JIN Yong-Juan

    2005-01-01

    @@ The application of the lattice Boltzmann method to the large vessel bifurcation blood flow is investigated in awide range of Reynolds numbers. The velocity, shear stress and pressure distributions at the bifurcation arepresented in detail. The flow separation zones revealed with increase of Reynolds number are located in theareas of the daughter branches distal to the outer corners of the bifurcation where some deposition of particularblood components might occur to form arteriosclerosis. The results also demonstrate that the lattice Boltzmannmethod is adaptive to simulating the flow in larger vessels under a high Reynolds number.

  1. Imaging polarimetry and retinal blood vessel quantification at the epiretinal membrane

    Science.gov (United States)

    Miura, Masahiro; Elsner, Ann E.; Cheney, Michael C.; Usui, Masahiko; Iwasaki, Takuya

    2007-05-01

    We evaluated a polarimetry method to enhance retinal blood vessels masked by the epiretinal membrane. Depolarized light images were computed by removing the polarization retaining light reaching the instrument and were compared with parallel polarized light images, average reflectance images, and the corresponding images at 514 nm. Contrasts were computed for retinal vessel profiles for arteries and veins. Contrasts were higher in the 514 nm images in normal eyes but higher in the depolarized light image in the eyes with epiretinal membranes. Depolarized light images were useful for examining the retinal vasculature in the presence of retinal disease.

  2. Generation of functionally competent and durable engineered blood vessels from human induced pluripotent stem cells.

    Science.gov (United States)

    Samuel, Rekha; Daheron, Laurence; Liao, Shan; Vardam, Trupti; Kamoun, Walid S; Batista, Ana; Buecker, Christa; Schäfer, Richard; Han, Xiaoxing; Au, Patrick; Scadden, David T; Duda, Dan G; Fukumura, Dai; Jain, Rakesh K

    2013-07-30

    Efficient generation of competent vasculogenic cells is a critical challenge of human induced pluripotent stem (hiPS) cell-based regenerative medicine. Biologically relevant systems to assess functionality of the engineered vessels in vivo are equally important for such development. Here, we report a unique approach for the derivation of endothelial precursor cells from hiPS cells using a triple combination of selection markers--CD34, neuropilin 1, and human kinase insert domain-containing receptor--and an efficient 2D culture system for hiPS cell-derived endothelial precursor cell expansion. With these methods, we successfully generated endothelial cells (ECs) from hiPS cells obtained from healthy donors and formed stable functional blood vessels in vivo, lasting for 280 d in mice. In addition, we developed an approach to generate mesenchymal precursor cells (MPCs) from hiPS cells in parallel. Moreover, we successfully generated functional blood vessels in vivo using these ECs and MPCs derived from the same hiPS cell line. These data provide proof of the principle that autologous hiPS cell-derived vascular precursors can be used for in vivo applications, once safety and immunological issues of hiPS-based cellular therapy have been resolved. Additionally, the durability of hiPS-derived blood vessels in vivo demonstrates a potential translation of this approach in long-term vascularization for tissue engineering and treatment of vascular diseases. Of note, we have also successfully generated ECs and MPCs from type 1 diabetic patient-derived hiPS cell lines and use them to generate blood vessels in vivo, which is an important milestone toward clinical translation of this approach.

  3. Screening of specific binding peptide targeting blood vessel of human esophageal cancer in vivo in mice

    Institute of Scientific and Technical Information of China (English)

    ZHI Min; WU Kai-chun; HAO Zhi-ming; GUO Chang-cun; YAO Jia-yin

    2011-01-01

    Background Cancer of the esophagus and gastroesophageal junction remains a virulent malignancy with poor prognosis. Rapid progresses were made in chemotherapeutic agents and the development of molecular markers allowed better identification of candidates for targeted therapy. This study aimed to identify the candidate peptides used for anti-angiogenic therapy of esophageal cancer by in vivo screening C7C peptide library for peptides binding specifically to blood vessels of human esophageal cancer.Methods The phage displayed C7C peptide library was injected intravenously into mice bearing human esophageal tumor xenografts under renal capsule. After 5 rounds of screening, 13 clones were picked up individually and sequenced.During each round of screening, titers of phage recovery were calculated from tumor xenograft and control tissues.Homing of these 9 peptides to tumor vessel was detected by calculating phage titers in the tumor xenograft and control tissues (lung and spleen) after each phage was injected into mice model, and compared with the distribution of phage M13 and Ⅷ-related antigen in tumor xenograft by immunohistochemical staining. Comparisons among groups of data were made using one-way analysis of variance (ANOVA), followed by the Bonferroni multiple comparisons test.Results The number of phage recovered from tumor tissue of each round increased gradually in tumor group while decreased in control groups (P <0.01 in tumor and spleen, P <0.05 in lung). Immunohistochemical staining showed similar staining pattern with M13 antibody or Ⅷ-related antigen antibody, suggesting that phages displaying the selected peptides could home to blood vessel of human esophageal cancer. According to their DNA, 9 corresponding peptide sequences were deduced. And the homing ability to blood vessel of phages displaying the selected peptides was confirmed by comparing with their recovery in tumor and control tissues. Two motifs, YSXNXW and PXNXXN, were also obtained by

  4. 应力缓压式种植修复体的临床应用研究%Clinical application of the stress relief pressure kind of implant prosthesis

    Institute of Scientific and Technical Information of China (English)

    李俊; 黄隆龙

    2012-01-01

    目的 研究应力缓压式种植修复体在临床上的应用效果,探讨全瓷冠修复体在种植体冠修复的应用方法.方法 选择临床30例患者的33颗后牙种植体进行种植后行应力缓压式单颗-螺丝固位-全瓷-种植体支持固定义齿修复,并进行随访、分析.结果 经过1年随访,除1例患者因种植体松动导致修复失败外,另29例32颗种植体冠修复效果良好无1例出现瓷裂,崩瓷,螺丝折断,修复体脱落等现象.结论 应力缓压式种植修复体取得了满意的修复效果,具有良好的临床应用前景.%Objective To study the stress relief pressure kind of implant prosthesis in clinical application and discuss the results of all ceramic crown restorations in the application of implant crowns. Methods 30 patients' 33 posterior teeth's implants,after implantation, underwent single stress relief pressure-screw retaining-porcelain-implant-supported tixed denture restoration, and follow-up analysis. Results After one years follow-up,except one restorative failure due to implant loosening, the other 29 cases of 32 implant crowns worked well without cracking, porcelain collapsing,screw fracture,prosthesis off and etc. Conclusions Stress relief pressure kind of implants gets satisfactory results,with good prospects for clinical application.

  5. 肢体软组织肉瘤及受累大血管切除联合人工血管重建的临床研究%Clinical Study of Vascular Resection and Vascular Prosthesis in the Major Vessels Invaded by Soft Tissue Sarcomas of Extremity

    Institute of Scientific and Technical Information of China (English)

    韩毓; 曲兴龙; 张怡; 王炳; 柴宇啸

    2014-01-01

    目的:探讨肢体软组织肉瘤及受累的大血管切除联合人工血管重建的临床疗效。方法对19例累及肢体重要血管的软组织肉瘤患者行肿瘤屏障切除联合人工血管手术,8例同时重建动脉和静脉,4例重建动脉,7例重建静脉,均采用人工血管置换。观察术后血管通畅及肿瘤复发情况。结果无1例出现重建血管感染,伤口均一期愈合。全部患者随访3~32个月,平均18个月。随访期间重建动、静脉通畅率分别为100%和46%,未见肿瘤复发。结论肢体软组织肉瘤累及重要血管进行切除联合人工血管重建安全可靠,能提高切除率,降低肿瘤复发率。%Objective To explore the clinical efficacy of major vascular resection and vascular prosthesis in the major vessels invaded by soft tissue sarcomas of extremity .Methods 19 patients with extremity soft tissue sarcomas invading major ves-sels underwent tumor resection and artificial vascular implantation .8 patients received combined reconstruction of arteries and veins,4 patients received artery reconstruction ,and 7 patients received venous reconstruction ,all using artificial vascular replace-ment .The vascular patency and tumor recurrence were observed after operation .Results None of the patients had revasculariza-tion infection and the wound all healed .19 patients were followed up for 3-32 months,and the average was 18 months.The arteries patency rate was 100%and the vessels patency rate was 46%,no tumor recurrence was found .Conclusion For the extremity soft tissue sarcoma patients with major vessels involvement ,tumor resection with artificial vessel implantation is safe and effective, and it can reduce recurrence and improve the tumor resection rate .

  6. 21 CFR 870.3450 - Vascular graft prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vascular graft prosthesis. 870.3450 Section 870... prosthesis. (a) Identification. A vascular graft prosthesis is an implanted device intended to repair... Prostheses 510(k) Submissions.”...

  7. 21 CFR 872.3950 - Glenoid fossa prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Glenoid fossa prosthesis. 872.3950 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the...

  8. 21 CFR 888.3025 - Passive tendon prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Passive tendon prosthesis. 888.3025 Section 888...) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3025 Passive tendon prosthesis. (a) Identification. A passive tendon prosthesis is a device intended to be implanted made of silicon elastomer or...

  9. Medpor义眼座植入术矫正眼窝凹陷畸形临床观察%Clinical observation of Medpor ocular prosthesis implantation to correct sunken socket abnormality

    Institute of Scientific and Technical Information of China (English)

    杜刚; 李贵刚; 谈清明

    2011-01-01

    Objective To discuss clinical effect observation of porous polythene ocular prosthesis ( Medpor ) implantation to correct sunken socket abnormality. Methods Optionality conduct Medpor or HA ocular prosthesis implantation to 55 cases of patients without eyeball or contracted eyeball or anophthalmia or eyeball atrophy resulting in socket sinking deformity. After postoperative follow-up over 6 months, Both of the clinical effectiveness in all cases were analyzed from complications, such as extrusion, migration or infection of the implant, etc. Results Both of the therapeutic effect of the ocular prosthesis implantation to correct sunken socket abnormality is good, but Medpor has less complications. Conclusion The overall of therapeutic effect of Medpor implantation to treat sunken Socket abnormality is better. Medpor is shown to be biocompatible and an ideal material for socket sinking defomity.%目的 探讨多孔聚乙烯义眼座(Medpor)植入矫正眼窝凹陷畸形手术效果.方法 55例(55只眼)包括眼球萎缩、眼球摘除术后、眼内容摘除术后及合并结膜囊狭窄的患者,随机植入Medpor义眼座或羟基磷灰石义眼座,随访观察术后义眼座暴露、感染等并发症情况,比较手术疗效.结果 Medpor义眼座与羟基磷灰石义眼座能取得相同的良好的治疗效果,但前者并发症更少.结论 Medpor义眼座植入术疗效可靠,Medpor具有良好的组织相容性,是矫正眼窝凹陷畸形的理想材料.

  10. Endocan immunoreactivity in the mouse brain: method for identifying nonfunctional blood vessels

    Science.gov (United States)

    Frahm, Krystle A.; Nash, Connor P.; Tobet, Stuart A.

    2013-01-01

    Endocan is a secreted proteoglycan that has been shown to indicate angiogenic activity: remodeling in several tumor types in humans and mice. Serum endocan levels also indicate prognosis and has been proposed as a biomarker for certain cancers. Recently, monoclonal antibodies directed against mouse endocan have been developed allowing for further characterization of endocan function and potentially as a marker for angiogenesis through immunoreactivity in endothelial tip cells. The results of the current study show that endocan immunoreactivity in the mouse brain is present in blood vascular networks including but not limited to the cortex, hippocampus and paraventricular nucleus of the hypothalamus in C57BL/6J and FVB/N mice. Endocan immunoreactivity did not vary during postnatal development or by sex. Interestingly, after vascular perfusion with fluorescein isothiocyanate (FITC), endothelial cells positive for FITC were immunonegative for endocan suggesting FITC interference with the immunohistochemistry. A small number of FITC-negative blood vessels were endocan immunoreactive suggesting the identification of new blood vessels that are not yet functional. The current study shows that endocan is normally present in the mouse brain and prior vascular perfusion with FITC may provide a useful tool for identify newly forming blood vessels. PMID:24055127

  11. Threadlike bundle of tubules running inside blood vessels New anatomical structure

    CERN Document Server

    Jiang, X; Shin, H; Lee, B; Choi, C; Soh, K; Cheun, B; Baik, K; Soh, K; Jiang, Xiaowen; Kim, Hee-kyeong; Shin, Hak-soo; Lee, Byong-chon; Choi, Chunho; Soh, Kyung-soon; Cheun, Byeung-soo; Baik, Ku-youn; Soh, Kwang-sup

    2002-01-01

    According to current anatomy, the arteries and veins do not have threadlike structures running inside the vessels. Despite such prevailing knowledge here we report on observation of a novel structure inside the blood vessels of rats and rabbits, which is a semi-transparent elastic bundle of tubules whose diameters are of 10$\\mu$m order. This is a rediscovery of the Bong Han ducts1,2 which have not been confirmed because the observing method was not known. We found a new procedure of observing the intra blood vessel ducts (IBVD) which are too thin, fragile, and semi-transparent to be detected in ordinary surgical operation. The method we contrived is to let blood be coagulated around the IBVD so that they become thick and strong by intravenous injection of 10 per cent dextrose solution at the vena femoralis. A piece of thickened IBVD sample is treated with urokinase to remove blood clots and the thin thread of IBVD is embedded inside of a string of fibrin

  12. In vivo measurement of hemodynamic information in stenosed rat blood vessels using X-ray PIV

    Science.gov (United States)

    Park, Hanwook; Park, Jun Hong; Lee, Sang Joon

    2016-11-01

    Measurements of the hemodynamic information of blood flows, especially wall shear stress (WSS), in animal models with circulatory vascular diseases (CVDs) are important to understand the pathological mechanism of CVDs. In this study, X-ray particle image velocimetry (PIV) with high spatial resolution was applied to obtain velocity field information in stenosed blood vessels with high WSS. 3D clips fabricated with a 3D printer were applied to the abdominal aorta of a rat cadaver to induce artificial stenosis in the real blood vessel of an animal model. The velocity and WSS information of blood flows in the stenosed vessel were obtained and compared at various stenosis severities. In vivo measurement was also conducted by fastening a stenotic clip on a live rat model through surgical intervention to reduce the flow rate to match the limited temporal resolution of the present X-ray PIV system. Further improvement of the temporal resolution of the system might be able to provide in vivo measurements of hemodynamic information from animal disease models under physiological conditions. The present results would be helpful for understanding the relation between hemodynamic characteristics and the pathological mechanism in animal CVD models.

  13. Active Path Selection of Fluid Microcapsules in Artificial Blood Vessel by Acoustic Radiation Force

    Science.gov (United States)

    Masuda, Kohji; Muramatsu, Yusuke; Ueda, Sawami; Nakamoto, Ryusuke; Nakayashiki, Yusuke; Ishihara, Ken

    2009-07-01

    Micrometer-sized microcapsules collapse upon exposure to ultrasound. Use of this phenomenon for a drug delivery system (DDS), not only for local delivery of medication but also for gene therapy, should be possible. However, enhancing the efficiency of medication is limited because capsules in suspension diffuse in the human body after injection, since the motion of capsules in blood flow cannot be controlled. To control the behavior of microcapsules, acoustic radiation force was introduced. We detected local changes in microcapsule density by producing acoustic radiation force in an artificial blood vessel. Furthermore, we theoretically estimated the conditions required for active path selection of capsules at a bifurcation point in the artificial blood vessel. We observed the difference in capsule density at both in the bifurcation point and in alternative paths downstream of the bifurcation point for different acoustic radiation forces. Comparing the experimental results with those obtained theoretically, the conditions for active path selection were calculated from the acoustic radiation force and fluid resistance of the capsules. The possibility of controlling capsule flow towards a specific point in a blood vessel was demonstrated.

  14. Retinal hemodynamic oxygen reactivity assessed by perfusion velocity, blood oximetry and vessel diameter measurements

    DEFF Research Database (Denmark)

    Klefter, Oliver Niels; Lauritsen, Anne Øberg; Larsen, Michael

    2015-01-01

    PURPOSE: To test the oxygen reactivity of a fundus photographic method of measuring macular perfusion velocity and to integrate macular perfusion velocities with measurements of retinal vessel diameters and blood oxygen saturation. METHODS: Sixteen eyes in 16 healthy volunteers were studied at two...... examination sessions using motion-contrast velocimetry and retinal oximetry with vessel diameter corrections. To test oxygen reactivity, participants were examined during normoxia, after 15 min of hyperoxia and finally after 45 min of normoxia. Repeatability was assessed by intraclass correlation coefficients...... retinal arterial oxygen saturation from 95.1 ± 5.0% to 96.6 ± 6.4% (p = 0.038) and increased retinal venous oxygen saturation from 62.9 ± 6.7% to 70.3 ± 7.8% (p = 0.0010). Parameters returned to baseline levels after subsequent normoxia. Saturation and vessel diameter ICCs were 0.88-0.98 (range...

  15. Cerebral blood flow in small vessel disease: A systematic review and meta-analysis.

    Science.gov (United States)

    Shi, Yulu; Thrippleton, Michael J; Makin, Stephen D; Marshall, Ian; Geerlings, Mirjam I; de Craen, Anton Jm; van Buchem, Mark A; Wardlaw, Joanna M

    2016-10-01

    White matter hyperintensities are frequent on neuroimaging of older people and are a key feature of cerebral small vessel disease. They are commonly attributed to chronic hypoperfusion, although whether low cerebral blood flow is cause or effect is unclear. We systematically reviewed studies that assessed cerebral blood flow in small vessel disease patients, performed meta-analysis and sensitivity analysis of potential confounders. Thirty-eight studies (n = 4006) met the inclusion criteria, including four longitudinal and 34 cross-sectional studies. Most cerebral blood flow data were from grey matter. Twenty-four cross-sectional studies (n = 1161) were meta-analysed, showing that cerebral blood flow was lower in subjects with more white matter hyperintensity, globally and in most grey and white matter regions (e.g. mean global cerebral blood flow: standardised mean difference-0.71, 95% CI -1.12, -0.30). These cerebral blood flow differences were attenuated by excluding studies in dementia or that lacked age-matching. Four longitudinal studies (n = 1079) gave differing results, e.g., more baseline white matter hyperintensity predated falling cerebral blood flow (3.9 years, n = 575); cerebral blood flow was low in regions that developed white matter hyperintensity (1.5 years, n = 40). Cerebral blood flow is lower in subjects with more white matter hyperintensity cross-sectionally, but evidence for falling cerebral blood flow predating increasing white matter hyperintensity is conflicting. Future studies should be longitudinal, obtain more white matter data, use better age-correction and stratify by clinical diagnosis.

  16. Clinical analysis and processing of the active prosthesis implantation after epithelial implantation cysts%活动义眼植入术后上皮植入性囊肿的临床分析及处理

    Institute of Scientific and Technical Information of China (English)

    张永雪; 杨倩倩; 刘德成

    2015-01-01

    Objective To investigate the clinical effect of activities prosthesis implantation after epithelial implantation cysts. Methods With the help of local anesthesia and the microscope,to use microscopic tweezers to filed the cyst by organization,cut conjunctiva horizontally,and separate the cyst in order to exposure the cyst fully and remove the cyst.Doctors should be careful when they separate the cyst.Avoiding wear out capsule wall residual causes recurrence of cyst. Results 32 cases(32 eyes) with the help of epithelial implantation cyst, the cyst appears circular approximately, oval or nodular.The cyst appears translucence,soft texture, and the capsule wall was completed without break. Pathological diagnosis Dermoid cyst,container in the cyst was thick liquid, and inter has keratinized tissue.There was no recurrence among the 32 cases,install Prosthetic eyes after three months, and the eyes symmetry was very good. Conclusion Surgery is the only effective way for epithelial implantation cyst.Under Microscope descending activity after prosthesis implantation of epithelial implantation cysts is safe,reliable,less damage, and no recurrence.%目的:探讨活动义眼植入术后上皮植入性囊肿的临床治疗效果。方法:局麻下,于显微镜下,用显微镊子把囊肿旁的组织提起,水平剪开结膜,分离囊肿,充分暴露囊肿将其摘除,分离囊肿时应小心剥离,避免穿破囊壁残留引起囊肿复发。结果:32例(32眼)上皮植入性囊肿,囊肿近似圆形、椭圆形或结节状,呈半透明,质地软,囊壁完整无破裂。病理诊断:皮样囊肿,囊内容物为浆液行,间有角化组织。32例术后无复发,3个月安装义眼片,双眼对称良好。结论:手术是治疗上皮植入囊肿的唯一有效方法。显微镜下行活动义眼植入术后的上皮植入性囊肿取出术,安全可靠,损伤小,无复发。

  17. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

    Directory of Open Access Journals (Sweden)

    William Ruger Porter

    Full Text Available Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange. Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana was investigated using a differential-contrast, dual-vascular injection (DCDVI technique and high-resolution X-ray microcomputed tomography (μCT. Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory

  18. Vascular Patterns in Iguanas and Other Squamates: Blood Vessels and Sites of Thermal Exchange.

    Science.gov (United States)

    Porter, William Ruger; Witmer, Lawrence M

    2015-01-01

    Squamates use the circulatory system to regulate body and head temperatures during both heating and cooling. The flexibility of this system, which possibly exceeds that of endotherms, offers a number of physiological mechanisms to gain or retain heat (e.g., increase peripheral blood flow and heart rate, cooling the head to prolong basking time for the body) as well as to shed heat (modulate peripheral blood flow, expose sites of thermal exchange). Squamates also have the ability to establish and maintain the same head-to-body temperature differential that birds, crocodilians, and mammals demonstrate, but without a discrete rete or other vascular physiological device. Squamates offer important anatomical and phylogenetic evidence for the inference of the blood vessels of dinosaurs and other extinct archosaurs in that they shed light on the basal diapsid condition. Given this basal positioning, squamates likewise inform and constrain the range of physiological thermoregulatory mechanisms that may have been found in Dinosauria. Unfortunately, the literature on squamate vascular anatomy is limited. Cephalic vascular anatomy of green iguanas (Iguana iguana) was investigated using a differential-contrast, dual-vascular injection (DCDVI) technique and high-resolution X-ray microcomputed tomography (μCT). Blood vessels were digitally segmented to create a surface representation of vascular pathways. Known sites of thermal exchange, consisting of the oral, nasal, and orbital regions, were given special attention due to their role in brain and cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and to assess their ability to deliver cooled blood to the dural venous sinuses. Arteries within sites of thermal exchange were found to deliver blood directly and through collateral pathways. The venous drainage was found to have multiple pathways that could influence neurosensory tissue temperature

  19. Rehabilitation of dentition defect with severe teeth attrition using implant-supported prosthesis combined with conventional prosthesis%10例牙齿重度磨损伴牙列缺损种植修复与咬合重建

    Institute of Scientific and Technical Information of China (English)

    罗新宇; 倪峰; 柏全民; 朴东信

    2015-01-01

    AIM:To evaluate the effect of rehabilitation of dentition defect with severe teeth attrition using implant-supported prosthesis combined with traditional prosthesis.METHODS:10 Patients of dentition defect with severe teeth attrition were treated.The provisional restorations were used to restore vertical dimension of occlusion and to adjust the jaw position to rest position.Then implant-supported prosthesis combined with fixed prosthesis was used for dentition rehabilitation the 10 patients received 57 implants.Clinical parameters concerning implants and restora-tions were evaluated at follow-up visits patients were followed up for 3 1 -40 month.RESULTS:All patients main-tained good oral hygiene;implant survival rate was 100%,and implant success rate was 96.6%.2 implants in 2 pa-tients had alveolar bone loss (1 .8 mm)and soft tissue recession (1 .5 mm)without compromised aesthetic result.All patients were satisfied with function,aesthetics and comfort.Neither complications related to TMJ nor masseter muscle disorders was observed.CONCLUSION:Rehabilitation using implant-supported prosthesis combined with traditional prosthesis for patients with dentition defect and sever teeth attrition can effectively restore their facial esthetics and oral function.%目的:探讨牙齿重度磨损伴牙列缺损(缺失)种植修复与咬合重建联合治疗的疗效。方法:选择牙齿重度磨损伴牙列缺损(缺失)而致咬合关系紊乱的患者10例,通过暂时修复体进行过渡修复以恢复生理性垂直距离,使患者颌位调整到舒适位,再行种植体支持式固定义齿或覆盖义齿修复,并在种植义齿修复的同时对磨损牙进行固定义齿修复,完成咬合重建。随访31~41个月(平均36个月),评价患者社区牙周指数、种植体骨结合、种植体周围软组织以及患者满意度。结果:10例患者共植入57个种植体;种植体3年存留率100%,成功率96.6%;2例(2枚

  20. Morphologic study of the blood vessels of the superior cervical ganglion of the albino rat.

    Science.gov (United States)

    DePace, D M

    1981-01-01

    Blood vessels of the rat superior cervical ganglion were examined by both light and electron microscopy. Direct blood supply to the superior cervical ganglion was derived from a capsular plexus of vessels. Intraganglionic vessels were for the most part capillaries. Some of these capillaries appeared dilated and sinusoidal. Although the ganglion did not seem to be densely vascularized, there was sufficient distribution to accommodate the nerve cell bodies of the ganglion. Individual capillaries served groups of neurons. Occasionally, capillary loops could be observed to surround single neuron perikarya. Ultrastructural studies revealed the presence of two types of capillaries. The majority of the capillaries of the rat superior cervical ganglion demonstrated a continuous, non-fenestrated endothelium. Typical junctional complexes were found on abutting endothelial surfaces. Endothelial flaps and microvilli were also observed on the luminal surface of some of the vessels. Numerous micropinocytotic vesicles were observed on both the luminal and abluminal surfaces of the endothelium. A small number of capillaries demonstrated a fenestrated endothelium. In both types of capillaries there was a basement membrane and an extracellular space containing collagen. Perikaryal cytoplasm was separated from the extracellular space by a thick layer of satellite cell cytoplasm.

  1. An Automatic Cognitive Graph-Based Segmentation for Detection of Blood Vessels in Retinal Images

    Directory of Open Access Journals (Sweden)

    Rasha Al Shehhi

    2016-01-01

    Full Text Available This paper presents a hierarchical graph-based segmentation for blood vessel detection in digital retinal images. This segmentation employs some of perceptual Gestalt principles: similarity, closure, continuity, and proximity to merge segments into coherent connected vessel-like patterns. The integration of Gestalt principles is based on object-based features (e.g., color and black top-hat (BTH morphology and context and graph-analysis algorithms (e.g., Dijkstra path. The segmentation framework consists of two main steps: preprocessing and multiscale graph-based segmentation. Preprocessing is to enhance lighting condition, due to low illumination contrast, and to construct necessary features to enhance vessel structure due to sensitivity of vessel patterns to multiscale/multiorientation structure. Graph-based segmentation is to decrease computational processing required for region of interest into most semantic objects. The segmentation was evaluated on three publicly available datasets. Experimental results show that preprocessing stage achieves better results compared to state-of-the-art enhancement methods. The performance of the proposed graph-based segmentation is found to be consistent and comparable to other existing methods, with improved capability of detecting small/thin vessels.

  2. In Vivo μPIV Measurements of Blood Flow in Small Vessels of a Rat Model.

    Science.gov (United States)

    Wei, Timothy; Conner, Nadine; Russell, John; Legac, Paul

    2007-11-01

    Ongoing research at the University of Wisconsin Medical School is addressing the effects of perfusion of glottal tissue on voice production. Building on the approach developed by Gharib's group at CalTech for embryonic zebra fish, we have modified μPIV to measure flow in capillaries and small blood vessels in a live rat model. In lieu of seeding particles, the DPIV correlation algorithm tracks the motion of red blood cells moving through these vessels. The methodology will be presented along with a video sequence showing measurements made from muscle tissue laid nominally flat on a microscope stage. Challenges of measurements in three-dimensional geometries, i.e. the throat, will be discussed.

  3. Regulation of monocyte cell fate by blood vessels mediated by Notch signalling.

    Science.gov (United States)

    Gamrekelashvili, Jaba; Giagnorio, Roberto; Jussofie, Jasmin; Soehnlein, Oliver; Duchene, Johan; Briseño, Carlos G; Ramasamy, Saravana K; Krishnasamy, Kashyap; Limbourg, Anne; Kapanadze, Tamar; Ishifune, Chieko; Hinkel, Rabea; Radtke, Freddy; Strobl, Lothar J; Zimber-Strobl, Ursula; Napp, L Christian; Bauersachs, Johann; Haller, Hermann; Yasutomo, Koji; Kupatt, Christian; Murphy, Kenneth M; Adams, Ralf H; Weber, Christian; Limbourg, Florian P

    2016-08-31

    A population of monocytes, known as Ly6C(lo) monocytes, patrol blood vessels by crawling along the vascular endothelium. Here we show that endothelial cells control their origin through Notch signalling. Using combinations of conditional genetic deletion strategies and cell-fate tracking experiments we show that Notch2 regulates conversion of Ly6C(hi) monocytes into Ly6C(lo) monocytes in vivo and in vitro, thereby regulating monocyte cell fate under steady-state conditions. This process is controlled by Notch ligand delta-like 1 (Dll1) expressed by a population of endothelial cells that constitute distinct vascular niches in the bone marrow and spleen in vivo, while culture on recombinant DLL1 induces monocyte conversion in vitro. Thus, blood vessels regulate monocyte conversion, a form of committed myeloid cell fate regulation.

  4. [Which is right? "Theory of channel" or "Theory of blood vessels"].

    Science.gov (United States)

    Liu, Cheng-Zhong

    2006-10-01

    The ancient medical science of Jingmai (Channel or blood vessel) applied the running sensation along channels of the so-called "Mai" to diagnose and treat diseases. Unfortunately, this had been lost in the Han Dynasty. Related information is recorded in the official history; there are related evidences in the unearthed Mai shu (The Book of Channel) and "Mairen (The Statue of Channel)", including the rediscovery and modern researches on the running sensation along channels; the successful cases of diagnosis and treatment by the method of running sensation along channels. The scholars supported the theory of blood vessel query the above ideas, which need to assemble large numbers of researches of the theory of channel to resolve the problems.

  5. A SURVEY OF RETINA BASED DISEASE IDENTIFICATION USING BLOOD VESSEL SEGMENTATION

    Directory of Open Access Journals (Sweden)

    P Kuppusamy

    2016-11-01

    Full Text Available The colour retinal photography is one of the most essential features to identify the confirmation of various eye diseases. The iris is primary attribute to authenticate the human. This research work presents the survey and comparison of various blood vessel related feature identification, segmentation, extraction and enhancement methods. Additionally, this study is observed the various databases performance for storing the images and testing in minimal time. This paper is also provides the better performance techniques based on the survey.

  6. First two cases of living related liver transplantation with complicated anatomy of blood vessels in Beijing

    OpenAIRE

    Wu, Wen-Han; Wan, Yuan-Lian; Lee, Long; Yang, Yin-Mo; Huang, Yan-Ting; Chen, Chao-Long; Fan, Sheung-Tat

    2004-01-01

    Aim: Living related liver transplantation (LRLT) has been developed in response to the paediatric organ donor shortage. Though it has been succeeded in many centers worldwide, the safety of the donor is still a major concern, especially in donors with anatomy variation. We succeeded in performing the first two cases of living related liver transplantation with complicated anatomy of blood vessels as a way to overcome cadaveric organ shortage in Beijing. Methods: Two patients, with congenital ...

  7. Human Blood-Vessel-Derived Stem Cells for Tissue Repair and Regeneration

    Directory of Open Access Journals (Sweden)

    Chien-Wen Chen

    2012-01-01

    Full Text Available Multipotent stem/progenitor cells with similar developmental potentials have been independently identified from diverse human tissue/organ cultures. The increasing recognition of the vascular/perivascular origin of mesenchymal precursors suggested blood vessels being a systemic source of adult stem/progenitor cells. Our group and other laboratories recently isolated multiple stem/progenitor cell subsets from blood vessels of adult human tissues. Each of the three structural layers of blood vessels: intima, media, and adventitia has been found to include at least one precursor population, that is, myogenic endothelial cells (MECs, pericytes, and adventitial cells (ACs, respectively. MECs and pericytes efficiently regenerate myofibers in injured and dystrophic skeletal muscles as well as improve cardiac function after myocardial infarction. The applications of ACs in vascular remodeling and angiogenesis/vasculogenesis have been examined. Our recent finding that MECs and pericytes can be purified from cryogenically banked human primary muscle cell culture further indicates their potential applications in personalized regenerative medicine.

  8. Effect of Electrical Stimulation on Blood Flow Velocity and Vessel Size

    Science.gov (United States)

    Jin, Hee-Kyung; Hwang, Tae-Yeon; Cho, Sung-Hyoun

    2017-01-01

    Abstract Interferential current electrical stimulation alters blood flow velocity and vessel size. We aimed to investigate the changes in the autonomic nervous system depending on electrical stimulation parameters. Forty-five healthy adult male and female subjects were studied. Bipolar adhesive pad electrodes were used to stimulate the autonomic nervous system at the thoracic vertebrae 1-4 levels for 20 min. Using Doppler ultrasonography, blood flow was measured to determine velocity and vessel size before, immediately after, and 30 min after electrical stimulation. Changes in blood flow velocity were significantly different immediately and 30 min after stimulation. The interaction between intervention periods and groups was significantly different between the exercise and pain stimulation groups immediately after stimulation (p<0.05). The vessel size was significantly different before and 30 min after stimulation (p<0.05). Imbalances in the sympathetic nervous system, which regulates balance throughout the body, may present with various symptoms. Therefore, in the clinical practice, the parameters of electrical stimulation should be selectively applied in accordance with various conditions and changes in form.

  9. Endovascular Electrodes for Electrical Stimulation of Blood Vessels for Vasoconstriction – a Finite Element Simulation Study

    Science.gov (United States)

    Kezurer, Noa; Farah, Nairouz; Mandel, Yossi

    2016-08-01

    Hemorrhagic shock accounts for 30–40 percent of trauma mortality, as bleeding may sometimes be hard to control. Application of short electrical pulses on blood vessels was recently shown to elicit robust vasoconstriction and reduction of blood loss following vascular injury. In this study we present a novel approach for vasoconstriction based on endovascular application of electrical pulses for situations where access to the vessel is limited. In addition to ease of access, we hypothesize that this novel approach will result in a localized and efficient vasoconstriction. Using computer modeling (COMSOL Multiphysics, Electric Currents Module), we studied the effect of endovascular pulsed electrical treatment on abdominal aorta of pigs, and compared the efficiency of different electrodes configurations on the electric field amplitude, homogeneity and locality when applied on a blood vessel wall. Results reveal that the optimal configuration is the endovascular approach where four electrodes are used, spaced 13 mm apart. Furthermore, computer based temperature investigations (bio-heat model, COMSOL Multiphysics) show that the maximum expected temperature rise is of 1.2 degrees; highlighting the safety of the four endovascular electrodes configuration. These results can aid in planning the application of endovascular pulsed electrical treatment as an efficient and safe vasoconstriction approach.

  10. Nitric oxide control of lower vertebrate blood vessels by vasomotor nerves.

    Science.gov (United States)

    Donald, John A; Broughton, Brad R S

    2005-10-01

    In mammals, much is understood about the endothelial and neural NO control mechanisms in the vasculature. In contrast, NO control of blood vessels in lower vertebrates is poorly understood, with the majority of research focusing on the presence of an endothelial NO system; however, its presence remains controversial. This study examined the mechanisms by which NO regulates the large blood vessels of non-mammalian vertebrates. In all species examined, the arteries and veins contained a plexus of NOS-positive perivascular nerves that included nerve bundles and fine, varicose nerve terminals. However, in the large arteries and veins of various species of fishes and amphibians, no anatomical evidence was found for endothelial NOS using both NADPH-diaphorase and eNOS immunohistochemistry. In contrast, perinuclear NOS staining was readily apparent in blue-tongue lizard, pigeon and rat, which suggested that eNOS first appeared in reptiles. Physiological analysis of NO signalling in the vascular smooth muscle of short-finned eel and cane toad could not find any evidence for endothelial NO signalling. In contrast, it appears that activation of the nitrergic vasomotor nerves is responsible for NO control of the blood vessels.

  11. Endovascular Electrodes for Electrical Stimulation of Blood Vessels for Vasoconstriction - a Finite Element Simulation Study.

    Science.gov (United States)

    Kezurer, Noa; Farah, Nairouz; Mandel, Yossi

    2016-08-18

    Hemorrhagic shock accounts for 30-40 percent of trauma mortality, as bleeding may sometimes be hard to control. Application of short electrical pulses on blood vessels was recently shown to elicit robust vasoconstriction and reduction of blood loss following vascular injury. In this study we present a novel approach for vasoconstriction based on endovascular application of electrical pulses for situations where access to the vessel is limited. In addition to ease of access, we hypothesize that this novel approach will result in a localized and efficient vasoconstriction. Using computer modeling (COMSOL Multiphysics, Electric Currents Module), we studied the effect of endovascular pulsed electrical treatment on abdominal aorta of pigs, and compared the efficiency of different electrodes configurations on the electric field amplitude, homogeneity and locality when applied on a blood vessel wall. Results reveal that the optimal configuration is the endovascular approach where four electrodes are used, spaced 13 mm apart. Furthermore, computer based temperature investigations (bio-heat model, COMSOL Multiphysics) show that the maximum expected temperature rise is of 1.2 degrees; highlighting the safety of the four endovascular electrodes configuration. These results can aid in planning the application of endovascular pulsed electrical treatment as an efficient and safe vasoconstriction approach.

  12. Microcirculation-on-a-Chip: A Microfluidic Platform for Assaying Blood- and Lymphatic-Vessel Permeability.

    Directory of Open Access Journals (Sweden)

    Miwa Sato

    Full Text Available We developed a microfluidic model of microcirculation containing both blood and lymphatic vessels for examining vascular permeability. The designed microfluidic device harbors upper and lower channels that are partly aligned and are separated by a porous membrane, and on this membrane, blood vascular endothelial cells (BECs and lymphatic endothelial cells (LECs were cocultured back-to-back. At cell-cell junctions of both BECs and LECs, claudin-5 and VE-cadherin were detected. The permeability coefficient measured here was lower than the value reported for isolated mammalian venules. Moreover, our results showed that the flow culture established in the device promoted the formation of endothelial cell-cell junctions, and that treatment with histamine, an inflammation-promoting substance, induced changes in the localization of tight and adherens junction-associated proteins and an increase in vascular permeability in the microdevice. These findings indicated that both BECs and LECs appeared to retain their functions in the microfluidic coculture platform. Using this microcirculation device, the vascular damage induced by habu snake venom was successfully assayed, and the assay time was reduced from 24 h to 30 min. This is the first report of a microcirculation model in which BECs and LECs were cocultured. Because the micromodel includes lymphatic vessels in addition to blood vessels, the model can be used to evaluate both vascular permeability and lymphatic return rate.

  13. Modeling the Role of the Glymphatic Pathway and Cerebral Blood Vessel Properties in Alzheimer's Disease Pathogenesis.

    Directory of Open Access Journals (Sweden)

    Christina Rose Kyrtsos

    Full Text Available Alzheimer's disease (AD is the most common cause of dementia in the elderly, affecting over 10% population over the age of 65 years. Clinically, AD is described by the symptom set of short term memory loss and cognitive decline, changes in mentation and behavior, and eventually long-term memory deficit as the disease progresses. On imaging studies, significant atrophy with subsequent increase in ventricular volume have been observed. Pathology on post-mortem brain specimens demonstrates the classic findings of increased beta amyloid (Aβ deposition and the presence of neurofibrillary tangles (NFTs within affected neurons. Neuroinflammation, dysregulation of blood-brain barrier transport and clearance, deposition of Aβ in cerebral blood vessels, vascular risk factors such as atherosclerosis and diabetes, and the presence of the apolipoprotein E4 allele have all been identified as playing possible roles in AD pathogenesis. Recent research has demonstrated the importance of the glymphatic system in the clearance of Aβ from the brain via the perivascular space surrounding cerebral blood vessels. Given the variety of hypotheses that have been proposed for AD pathogenesis, an interconnected, multilayer model offers a unique opportunity to combine these ideas into a single unifying model. Results of this model demonstrate the importance of vessel stiffness and heart rate in maintaining adequate clearance of Aβ from the brain.

  14. Modeling the Role of the Glymphatic Pathway and Cerebral Blood Vessel Properties in Alzheimer's Disease Pathogenesis.

    Science.gov (United States)

    Kyrtsos, Christina Rose; Baras, John S

    2015-01-01

    Alzheimer's disease (AD) is the most common cause of dementia in the elderly, affecting over 10% population over the age of 65 years. Clinically, AD is described by the symptom set of short term memory loss and cognitive decline, changes in mentation and behavior, and eventually long-term memory deficit as the disease progresses. On imaging studies, significant atrophy with subsequent increase in ventricular volume have been observed. Pathology on post-mortem brain specimens demonstrates the classic findings of increased beta amyloid (Aβ) deposition and the presence of neurofibrillary tangles (NFTs) within affected neurons. Neuroinflammation, dysregulation of blood-brain barrier transport and clearance, deposition of Aβ in cerebral blood vessels, vascular risk factors such as atherosclerosis and diabetes, and the presence of the apolipoprotein E4 allele have all been identified as playing possible roles in AD pathogenesis. Recent research has demonstrated the importance of the glymphatic system in the clearance of Aβ from the brain via the perivascular space surrounding cerebral blood vessels. Given the variety of hypotheses that have been proposed for AD pathogenesis, an interconnected, multilayer model offers a unique opportunity to combine these ideas into a single unifying model. Results of this model demonstrate the importance of vessel stiffness and heart rate in maintaining adequate clearance of Aβ from the brain.

  15. 新型中空硅橡胶睾丸假体移植术治疗睾丸缺失的临床体会(附13例报告)%Testicular prosthesis implantation with new-typed hollow silicone elastomer prosthesis: 13-case report

    Institute of Scientific and Technical Information of China (English)

    朱扬进; 宁晔; 陈慧兴; 平萍; 黄妹; 徐迪萍; 薄隽杰; 黄翼然; 李铮

    2012-01-01

    目的 评价新型中空硅橡胶睾丸假体阴囊移植术治疗男性睾丸缺失临床应用的安全性和有效性.方法 2009年1月至2011年3月,临床选择13例睾丸缺失者行睾丸假体植入术,包括:前列腺癌睾丸去势术2例、睾丸癌根治术5例、1侧无睾症2例、双侧无睾症1例、睾丸扭转坏死1例、睾丸萎缩1例、女性假两性畸形1例.睾丸假体为国产中空硅橡胶假体,13例中有4例在睾丸切除同时进行假体植入,另9例植入时间在睾丸切除6个月后;假体均为硅橡胶材料,睾丸假体的大小根据患者阴囊可容纳的空间及对侧睾丸大小来选择.结果 13例术后无感染、出血等并发症发生.手术6个月后进行随访;所有病例对植入睾丸假体后的阴囊外观及大小感到非常满意;对植入假体的重量:7例感到非常满意,5例感到较满意.全组无假体破裂及排异反应病例.结论 新型中空硅橡胶睾丸假体阴囊移植术治疗男性睾丸缺失能满足患者外观及心理的需要,临床表明安全有效.但长期生活质量及并发症还需进一步观察,设计更舒适及有功能的缓释型睾丸假体还需进一步研究.%Objective To investigate the effects and safety of the new-typed testicular prosthesis in the treatment of patients with absence of testis. Methods From Jan. 2009 to Mar. 2011, 13 patients (including 2 cases of prostate cancer, 5 cases of testicular cancer, 2 cases of unilateral anorchia, 1 case of bilateral anorchia, 1 case of testicular torsion, 1 case of orchiatrophy and 1 case of hermaphroditism) who had undergone testicular prosthesis implantation were recruited in this study. Four of the 13 cases immediately received testicular prosthesis implantation after orchiectomy, and other 9 cases received testicular prosthesis implantation 6 months later. The prosthesis was selected according to the conditions and volume of scrotum. Results Following-ups in the six months didn't show any

  16. The use of a masticatory robot to analyze the shock absorption capacity of different restorative materials for implant prosthesis

    Directory of Open Access Journals (Sweden)

    M. Menini

    2011-01-01

    Full Text Available The aim of the present research was to measure in vitro the chewing load forces transmitted through crowns made of different prosthetic restorative materials onto the dental implant. A masticatory robot that is able to reproduce the mandibular movements and the forces exerted during mastication was used. The forces transmitted to the simulated periimplant bone during the robot mastication were analysis of variance (ANOVA was used. The zirconia and the ceramic crowns transmitted significantly greater forces (p-value < 0.0001 than the other crowns tested. Dental materials with lower elastic modulus were better able to ansorb shock from acclusal forces than more rigid materials.

  17. 种植体-天然牙联合固定修复后牙区的临床评价%Clinical Study of Combined Implant-tooth-supported Fixed Dental Prosthesis in Posterior Region

    Institute of Scientific and Technical Information of China (English)

    黄颖荷; 李杏蕊; 董明新; 严俊; 林瑶

    2016-01-01

    Objective:To evaluate the clinical effects of implant-tooth supported fixed dental prosthesis in posterior region.Method:27 straummer implants were placed in the mandibles of 21 patients.After healing periods, implant-tooth supported fixed dental prosthesis were finished.Patients’self-feeling,implant-tooth’s clinical mobility and X-ray were measured during 6-48 months follow-up.Result:Subjective symptoms of the patients with good,all fixed crown bridge prosthesis were not loose and fall off,27 implants normal exercise masticatory function,implant retention rate was 100%,natural tooth and implant showed no abnormal X-ray transparent shadow.Conclusion:The fixed restorations supported by implant-tooth combination are proved to be satisfy by the clinical study of 6-48 months,and it is a good restore way for the missing teeth patients in posterior region.%目的:评价种植体-天然牙联合固定修复后牙区牙齿缺失的临床效果。方法:21例患者植入straummer种植体27枚,采用种植体-天然牙联合支持的金属烤瓷固定义齿修复缺失牙,并进行临床随访观察6~48个月。根据患者的自觉症状、天然牙及种植体的临床动度、种植体的存留率、义齿修复后种植体周围牙槽骨高度的X线片变化等进行评估。结果:患者的自觉症状良好,所有固定冠桥修复体均无松动、脱落,27枚种植体正常行使咀嚼功能,种植体的存留率为100%,天然牙和种植体周均未见异常X线透影区。结论:种植体-天然牙联合支持固定义齿修复后牙区48个月内的疗效满意,长期临床效果有待于进一步观察。

  18. Development and clinical application of a new testicular prosthesis

    Institute of Scientific and Technical Information of China (English)

    Ye Ning; Zhikang Cai; Huixing Chen; Ping Ping; Peng Li; Zhong Wang; Zheng Li

    2011-01-01

    A new type of testicular prosthesis made of silastic with an elliptical shape to mimic a normal testis was developed by our team and submitted for patenting in China.The prosthesis was produced in different sizes to imitate the normal testis of the patient.To investigate the effects and safety of the testicular prosthesis,20 patients receiving testicular prosthesis implantation were recruited for this study.Follow-up after 6 months revealed no complications in the patients.All the patients answered that they were satisfied with their body image and the position of the implants,19 patients were satisfied with the size and 16 patients were satisfied with the weight.These results show that the testicular prosthesis used in this study can meet patient's expectations.Patients undergoing orchiectomy should be offered the option to receive a testicular prosthesis implantation.The dimensions and weight of the available prosthetic implants should be further addressed to improve patient satisfaction.

  19. Effect of using nano and micro airborne abrasive particles on bond strength of implant abutment to prosthesis.

    Science.gov (United States)

    Rismanchian, Mansour; Davoudi, Amin; Shadmehr, Elham

    2015-01-01

    Connecting prostheses to the implant abutments has become a concern and achieving a satisfactory retention has been focused in cement-retention prostheses recently. Sandblasting is a method to make a roughened surface for providing more retention. The aim of this study was to compare effects of nano and micro airborne abrasive particles (ABAP) in roughening surface of implant abutments and further retention of cemented copings. Thirty Xive abutments and analogues (4.5 D GH1) were mounted vertically in self-cured acrylic blocks. Full metal Ni-Cr copings with a loop on the top were fabricated with appropriate marginal adaptation for each abutment. All samples were divided into 3 groups: first group (MPS) was sandblasted with 50 µm Al2O3 micro ABAP, second group (NSP) was sandblasted with 80 nm Al2O3 nano ABAP, and the third group (C) was assumed as control. The samples were cemented with provisional cement (Temp Bond) and tensile bond strength of cemented copings was evaluated by a universal testing machine after thermic cycling. The t test for independent samples was used for statistical analysis by SPSS software (version 15) at the significant level of 0.05. Final result showed significant difference among all groups (pABAP is an efficient way for increasing bond strengths significantly, but it seems that micro ABAP was more effective.

  20. Fixation of trapezial implants in a trapeziometacarpal total joint prosthesis tested in a model of porcine bone.

    Science.gov (United States)

    Hansen, Torben Bæk; Hengst, David; Mortensen, Jesper; Amstrup, Anders Læssøe

    2011-12-01

    High aseptic loosening rates have been reported in total joint prostheses of the carpometacarpal joint of the thumb, particularly in the trapezial component. The primary fixation of new implants may be tested in cadaver bones, but the anatomy of the pig is in many ways similar to that of the human, so we compared the central carpal bone from the forefoot of 6-month-old pigs, which has a saddle joint surface similar to the trapezium, to the trapezium in patients with carpometacarpal osteoarthritis. The mean (SD) bone mineral density of the 13 pig forefoot bones was 0.88 (0.12) g/cm(2) compared with 0.63 (0.16) g/cm(2) in the 31 human trapeziums. The measured size of the porcine bones was slightly larger than that of the human trapeziums. The similarity in form, size, and bone mineral density means that the central bone of the forefoot of 6-month-old pigs may be used for fixation tests in trapezial implants.

  1. Stemless shoulder prosthesis versus conventional anatomic shoulder prosthesis in patients with osteoarthritis

    OpenAIRE

    Berth, Alexander; Pap, Géza

    2012-01-01

    Background The stemless shoulder prosthesis is a new concept in shoulder arthroplasty. To date, only a few studies have investigated the results of this prosthesis. The aim of this study was to investigate the clinical and radiological midterm results of this implant in comparison with a standard anatomic stemmed shoulder prosthesis. Materials and methods The Constant score, the DASH score, the active range of motion (abduction, anteversion, external rotation), and the radiological results we...

  2. 硅胶假体植入隆鼻手术并发症的预防措施%Prevention Measures of the Complications of Silica Gel Prosthesis Implantation on Rhinoplasty

    Institute of Scientific and Technical Information of China (English)

    李雄艳; 杨丹; 谢志伟

    2013-01-01

    目的:通过各种预防措施或者手术方法,减少假体植入隆鼻手术并发症。方法:剖析并发症的发生原因,介绍并发症的预防措施。结果:317例假体植入隆鼻手术,除正常的局部术后肿胀外,除顾客对于审美意见不合一例外,无假体外露及感染以及排异等病例。结论:根据患者鼻型,雕刻合适的鼻假体,不能刻意通过假体抬高鼻尖,通过各种措施减少假体被污染的可能性,隆鼻手术并发症明显减少。%Objective To reduce the complications of silica gel prosthesis implantation on rhinoplasty by many prevention countermeasures and operation method. Methods The causes of complications were analyzed,and the prevention countermeasures of complications were introduced. Results In 317 cases of nose augmentation operation,except for local swelling and different customers’ aesthetic opinions,there were no prosthesis exposure and infection and rejection cases. Conclusion According to the patients’ nose,right nasal prosthesis is curved. Apex nasi should not be deliberately elevated through the nose prosthesis,and the possibility of prosthesis contamination be reduced through various measures. Nasal operation significantly reduce the complications of nose augmentation.

  3. Bionic prosthesis

    OpenAIRE

    МЫЛЬНИКОВ А.М.

    2015-01-01

    The real achievement in the prosthetics has become artificial joints that function as well as natural joints. Bionic limbs are the most advanced type of prosthesis at the moment. These electronic devices are made from synthetic materials, but the person can manage them using his/her own nervous system through the targeted muscle reinnervation (recovery disturbed innervation of organs and tissues surgically).Principle of operation of bionic prosthesis. After the amputation because of a serious...

  4. Automatic segmentation of blood vessels from retinal fundus images through image processing and data mining techniques

    Indian Academy of Sciences (India)

    R Geetharamani; Lakshmi Balasubramanian

    2015-09-01

    Machine Learning techniques have been useful in almost every field of concern. Data Mining, a branch of Machine Learning is one of the most extensively used techniques. The ever-increasing demands in the field of medicine are being addressed by computational approaches in which Big Data analysis, image processing and data mining are on top priority. These techniques have been exploited in the domain of ophthalmology for better retinal fundus image analysis. Blood vessels, one of the most significant retinal anatomical structures are analysed for diagnosis of many diseases like retinopathy, occlusion and many other vision threatening diseases. Vessel segmentation can also be a pre-processing step for segmentation of other retinal structures like optic disc, fovea, microneurysms, etc. In this paper, blood vessel segmentation is attempted through image processing and data mining techniques. The retinal blood vessels were segmented through color space conversion and color channel extraction, image pre-processing, Gabor filtering, image postprocessing, feature construction through application of principal component analysis, k-means clustering and first level classification using Naïve–Bayes classification algorithm and second level classification using C4.5 enhanced with bagging techniques. Association of every pixel against the feature vector necessitates Big Data analysis. The proposed methodology was evaluated on a publicly available database, STARE. The results reported 95.05% accuracy on entire dataset; however the accuracy was 95.20% on normal images and 94.89% on pathological images. A comparison of these results with the existing methodologies is also reported. This methodology can help ophthalmologists in better and faster analysis and hence early treatment to the patients.

  5. Aldehyde dehydrogenase-independent bioactivation of nitroglycerin in porcine and bovine blood vessels.

    Science.gov (United States)

    Neubauer, Regina; Wölkart, Gerald; Opelt, Marissa; Schwarzenegger, Christine; Hofinger, Marielies; Neubauer, Andrea; Kollau, Alexander; Schmidt, Kurt; Schrammel, Astrid; Mayer, Bernd

    2015-02-15

    The vascular bioactivation of the antianginal drug nitroglycerin (GTN), yielding 1,2-glycerol dinitrate and nitric oxide or a related activator of soluble guanylate cyclase, is catalyzed by aldehyde dehydrogenase-2 (ALDH2) in rodent and human blood vessels. The essential role of ALDH2 has been confirmed in many studies and is considered as general principle of GTN-induced vasodilation in mammals. However, this view is challenged by an early report showing that diphenyleneiodonium, which we recently characterized as potent ALDH2 inhibitor, has no effect on GTN-induced relaxation of bovine coronary arteries (De La Lande et al., 1996). We investigated this issue and found that inhibition of ALDH2 attenuates GTN-induced coronary vasodilation in isolated perfused rat hearts but has no effect on relaxation to GTN of bovine and porcine coronary arteries. This observation is explained by low levels of ALDH2 protein expression in bovine coronary arteries and several types of porcine blood vessels. ALDH2 mRNA expression and the rates of GTN denitration were similarly low, excluding a significant contribution of ALDH2 to the bioactivation of GTN in these vessels. Attempts to identify the responsible pathway with enzyme inhibitors did not provide conclusive evidence for the involvement of ALDH3A1, cytochrome P450, or GSH-S-transferase. Thus, the present manuscript describes a hitherto unrecognized pathway of GTN bioactivation in bovine and porcine blood vessels. If present in the human vasculature, this pathway might contribute to the therapeutic effects of organic nitrates that are not metabolized by ALDH2.

  6. Skeletonization algorithm-based blood vessel quantification using in vivo 3D photoacoustic imaging

    Science.gov (United States)

    Meiburger, K. M.; Nam, S. Y.; Chung, E.; Suggs, L. J.; Emelianov, S. Y.; Molinari, F.

    2016-11-01

    Blood vessels are the only system to provide nutrients and oxygen to every part of the body. Many diseases can have significant effects on blood vessel formation, so that the vascular network can be a cue to assess malicious tumor and ischemic tissues. Various imaging techniques can visualize blood vessel structure, but their applications are often constrained by either expensive costs, contrast agents, ionizing radiations, or a combination of the above. Photoacoustic imaging combines the high-contrast and spectroscopic-based specificity of optical imaging with the high spatial resolution of ultrasound imaging, and image contrast depends on optical absorption. This enables the detection of light absorbing chromophores such as hemoglobin with a greater penetration depth compared to purely optical techniques. We present here a skeletonization algorithm for vessel architectural analysis using non-invasive photoacoustic 3D images acquired without the administration of any exogenous contrast agents. 3D photoacoustic images were acquired on rats (n  =  4) in two different time points: before and after a burn surgery. A skeletonization technique based on the application of a vesselness filter and medial axis extraction is proposed to extract the vessel structure from the image data and six vascular parameters (number of vascular trees (NT), vascular density (VD), number of branches (NB), 2D distance metric (DM), inflection count metric (ICM), and sum of angles metric (SOAM)) were calculated from the skeleton. The parameters were compared (1) in locations with and without the burn wound on the same day and (2) in the same anatomic location before (control) and after the burn surgery. Four out of the six descriptors were statistically different (VD, NB, DM, ICM, p  <  0.05) when comparing two anatomic locations on the same day and when considering the same anatomic location at two separate times (i.e. before and after burn surgery). The study demonstrates an

  7. Mammalian Cardiovascular Patterning as Determined by Hemodynamic Forces and Blood Vessel Genetics

    Science.gov (United States)

    Anderson, Gregory Arthur

    Cardiovascular development is a process that involves the timing of multiple molecular events, and numerous subtle three-dimensional conformational changes. Traditional developmental biology techniques have provided large quantities of information as to how these complex organ systems develop. However, the major drawback of the majority of current developmental biological imaging is that they are two-dimensional in nature. It is now well recognized that circulation of blood is required for normal patterning and remodeling of blood vessels. Normal blood vessel formation is dependent upon a complex network of signaling pathways, and genetic mutations in these pathways leads to impaired vascular development, heart failure, and lethality. As such, it is not surprising that mutant mice with aberrant cardiovascular patterning are so common, since normal development requires proper coordination between three systems: the heart, the blood, and the vasculature. This thesis describes the implementation of a three-dimensional imaging technique, optical projection tomography (OPT), in conjunction with a computer-based registration algorithm to statistically analyze developmental differences in groups of wild-type mouse embryos. Embryos that differ by only a few hours' gestational time are shown to have developmental differences in blood vessel formation and heart development progression that can be discerned. This thesis describes how we analyzed mouse models of cardiovascular perturbation by OPT to detect morphological differences in embryonic development in both qualitative and quantitative ways. Both a blood vessel specific mutation and a cardiac specific mutation were analyzed, providing evidence that developmental defects of these types can be quantified. Finally, we describe the implementation of OPT imaging to identify statistically significant phenotypes from three different mouse models of cardiovascular perturbation across a range of developmental time points. Image

  8. Embolization: critical thrombus height, shear rates, and pulsatility. Patency of blood vessels.

    Science.gov (United States)

    Basmadjian, D

    1989-11-01

    The present article builds on elementary fluid dynamics and previous analyses by the author to delineate approximate boundaries of mural thrombus height Hp, maximum shear rate gamma Max, and flow pulsatility beyond which thrombi are subject to either very high or very low probabilities of embolization. A thrombus height of approximately 0.1 mm emerges as a critical dividing line: Below it, the maximum embolizing shear stress tau s is independent of thrombus height and varies only linearly with shear rate. Above it, tau s quickly approaches a strong quadratic dependence on both thrombus height and shear rate: tau s approximately (Hp gamma)2, significantly increasing the likelihood of an embolizing event. By contrast, convective-diffusive removal of blood components during the initial stages of thrombus formation varies only weakly with gamma 1/3 in all but the smallest vessels. These maximum embolizing stresses are due principally to fluid drag. Acceleration (pulsatile) forces only begin to make their presence felt at gamma less than 500 s-1 and reach parity with fluid drag at gamma approximately 10 s-1, i.e., at a level where the presence of pulsatility is questionable. The results are used to provide maps of domains with high and low probabilities of an embolytic event and of vessel patency. The maps reveal that relatively modest changes in shear rate and/or vessel lumen can cause shifts from high to low likelihood of vessel patency, opening up possible ways of controlling blockage by manipulation of these variables.

  9. Drug and light dose responses to focal photodynamic therapy of single blood vessels in vivo

    Science.gov (United States)

    Khurana, Mamta; Moriyama, Eduardo H.; Mariampillai, Adrian; Samkoe, Kimberley; Cramb, David; Wilson, Brian C.

    2009-11-01

    As part of an ongoing program to develop two-photon (2-γ) photodynamic therapy (PDT) for treatment of wet-form age-related macular degeneration (AMD) and other vascular pathologies, we have evaluated the reciprocity of drug-light doses in focal-PDT. We targeted individual arteries in a murine window chamber model, using primarily the clinical photosensitizer Visudyne/liposomal-verteporfin. Shortly after administration of the photosensitizer, a small region including an arteriole was selected and irradiated with varying light doses. Targeted and nearby vessels were observed for a maximum of 17 to 25 h to assess vascular shutdown, tapering, and dye leakage/occlusion. For a given end-point metric, there was reciprocity between the drug and light doses, i.e., the response correlated with the drug-light product (DLP). These results provide the first quantification of photosensitizer and light dose relationships for localized irradiation of a single blood vessel and are compared to the DLP required for vessel closure between 1-γ and 2-γ activation, between focal and broad-beam irradiation, and between verteporfin and a porphyrin dimer with high 2-γ cross section. Demonstration of reciprocity over a wide range of DLP is important for further development of focal PDT treatments, such as the targeting of feeder vessels in 2-γ PDT of AMD.

  10. Calcification in Chronically-Implanted Blood Pumps: Experimental Results and Review of the Literature

    OpenAIRE

    Turner, Stephen A.; Bossart, Mattie I.; Milam, John D.; Fuqua, John M.; Igo, Stephen R.; McGee, Michael G.; Frazier, O. Howard

    1982-01-01

    Blood compatibility is a major objective in the development of long-term, implantable circulatory assist (left ventricular assist devices) and replacement (total artificial heart) devices. An important problem in experimental studies in animals has been the propensity for calcification to occur at the blood/material interface. Presented is a summary of our experience (27 studies) with blood pump calcification and a review of the current literature regarding this complication.

  11. Observation of flow variation in capillaries of artificial blood vessel by producing microbubble aggregations.

    Science.gov (United States)

    Masuda, Kohji; Shigehara, Nobuhiko; Koda, Ren; Watarai, Nobuyuki; Ikeda, Seiichi; Arai, Fumihito; Miyamoto, Yoshitaka; Chiba, Toshio

    2012-01-01

    Microbubbles form their aggregations between the neighboring microbubbles by the effect of secondary Bjerknes force under ultrasound exposure. However, because of the difficulty to reproduce a capillary-mimicking artificial blood vessel, the behavior of aggregations in a capillary has not been predicted. Thus we prepared artificial blood vessels including a capillary model, which was made of poly(vinyl alcohol) (PVA) by grayscale lithography method, with minimum diameter of the path of 0.5 mm. By using this model we investigated the possibility of artificial embolization, where the microbubble aggregations might block entire vessels not to penetrate flow in downstream. Confirming that the sizes of flown aggregation were greater than the section area of the minimum path in the capillary model, we investigated the probability of path block in it. As the results we confirmed the probability increased in proportion to sound pressure and inversely to flow velocity. We are going to investigate with more kinds of parameters to enhance the possibility of artificial embolization.

  12. Surgical anatomy of the retroperitoneal spaces, Part III: Retroperitoneal blood vessels and lymphatics.

    Science.gov (United States)

    Mirilas, Petros; Skandalakis, John E

    2010-02-01

    In this article, we discuss the surgical anatomy of the blood vessels and the lymphatic vessels and lymph nodes found in the retroperitoneum. Retroperitoneal blood vessels include the aorta and all its branches--parietal and visceral--from the diaphragm to the pelvis, and the inferior vena cava and its tributaries. The retroperitoneal lymphatics form a very rich and extensive chain. As a general rule, lymphatics follow the arteries and named lymph nodes are found at the root of the arteries. Retroperitoneal nodes of the abdomen comprise the inferior diaphragmatic nodes and the lumbar nodes. The latter are classified as left lumbar (aortic), intermediate (interaorticovenous), and right lumbar (caval). These nodes surround the aorta and the inferior vena cava. Around the aorta lie the paraortic nodes, preaortic nodes (include celiac, superior mesenteric, inferior mesenteric nodes collecting lymph from the splanchna supplied by the homonymous arteries), and retroaortic nodes. Similarly, around the vena cava lie the paracaval, precaval, and retrocaval nodes. Pelvic nodes include the common iliac, external and internal iliac, obturator, and sacral nodes.

  13. In vivo bioimaging as a novel strategy to detect doxorubicin-induced damage to gonadal blood vessels.

    Directory of Open Access Journals (Sweden)

    Hadas Bar-Joseph

    Full Text Available INTRODUCTION: Chemotherapy may induce deleterious effects in normal tissues, leading to organ damage. Direct vascular injury is the least characterized side effect. Our aim was to establish a real-time, in vivo molecular imaging platform for evaluating the potential vascular toxicity of doxorubicin in mice. METHODS: Mice gonads served as reference organs. Mouse ovarian or testicular blood volume and femoral arterial blood flow were measured in real-time during and after doxorubicin (8 mg/kg intravenously or paclitaxel (1.2 mg/kg administration. Ovarian blood volume was imaged by ultrasound biomicroscopy (Vevo2100 with microbubbles as a contrast agent whereas testicular blood volume and blood flow as well as femoral arterial blood flow was imaged by pulse wave Doppler ultrasound. Visualization of ovarian and femoral microvasculature was obtained by fluorescence optical imaging system, equipped with a confocal fiber microscope (Cell-viZio. RESULTS: Using microbubbles as a contrast agent revealed a 33% (P<0.01 decrease in ovarian blood volume already 3 minutes after doxorubicin injection. Doppler ultrasound depicted the same phenomenon in testicular blood volume and blood flow. The femoral arterial blood flow was impaired in the same fashion. Cell-viZio imaging depicted a pattern of vessels' injury at around the same time after doxorubicin injection: the wall of the blood vessels became irregular and the fluorescence signal displayed in the small vessels was gradually diminished. Paclitaxel had no vascular effect. CONCLUSION: We have established a platform of innovative high-resolution molecular imaging, suitable for in vivo imaging of vessels' characteristics, arterial blood flow and organs blood volume that enable prolonged real-time detection of chemotherapy-induced effects in the same individuals. The acute reduction in gonadal and femoral blood flow and the impairment of the blood vessels wall may represent an acute universal doxorubicin

  14. Comparison between PVHIS on the MRI and the permeability of brain blood vessels in elderly patients

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Katsuhiko; Tanaka, Yuriko; Kubo, Hideki; Takagi, Yasushi; Tachikawa, Shinzo (Omotemachi Hospital, Tachikawa General Hospital, Tokyo (Japan)); Katsunuma, Hideyo

    1989-11-01

    The degree of PVHIS (periventricular high intensity signal) on the MRI was composed with the permeability of brain blood vessels using the cerebrospinal fluid (CSF)/serum ratio for albumin, and the CSF/serum ratio for IgG in elderly patients. The 47 elderly patients (mean age=79.9) were divided into three groups: (1) Mild group (20 cases, M:6, F:14, mean age=75.8), (2) Moderate group (18 cases, M:7, F:11, mean age=82.6), (3) Severe group (9 cases, M:2, F:7, mean age=82.9), in accordance with the degree of PVHIS on the MRI. The MRI was operated at a field strength of 0.22 tesla. The pulse sequence (used on all patients) had a repetition times (TR) of 2,000 msec and a time to echo (TE) of 40 msec. The levels of albumin and IgG in the serum and CSF were measured. The CSF/serum ratio for albumin was used of analyze the permeability of the brain blood vessels in each group. There was no significant difference in the level of the serum albumin, the CSF albumin, the serum IgG, the CSF IgG and the CSF/serum ratio for IgG among the three groups. The same was found to be true for the IgG index which indicates the synthesis of immunoglobulin in the central nervous system. However, there was a statistically significant difference (p<0.05) in the CSF/serum ratio for albumin between groups (1) and (3). The increased CSF/serum ratio for albumin in the severe group indicated there were confluent lesions involving the entire extent of the periventriular white matter on the MRI. This suggested an increased permeability of brain blood vessels which revealed the dysfunction of the blood brain barrier due to affected cerebral endothelial cells in capillaries. (author).

  15. Beam localization in HIFU temperature measurements using thermocouples, with application to cooling by large blood vessels.

    Science.gov (United States)

    Dasgupta, Subhashish; Banerjee, Rupak K; Hariharan, Prasanna; Myers, Matthew R

    2011-02-01

    Experimental studies of thermal effects in high-intensity focused ultrasound (HIFU) procedures are often performed with the aid of fine wire thermocouples positioned within tissue phantoms. Thermocouple measurements are subject to several types of error which must be accounted for before reliable inferences can be made on the basis of the measurements. Thermocouple artifact due to viscous heating is one source of error. A second is the uncertainty regarding the position of the beam relative to the target location or the thermocouple junction, due to the error in positioning the beam at the junction. This paper presents a method for determining the location of the beam relative to a fixed pair of thermocouples. The localization technique reduces the uncertainty introduced by positioning errors associated with very narrow HIFU beams. The technique is presented in the context of an investigation into the effect of blood flow through large vessels on the efficacy of HIFU procedures targeted near the vessel. Application of the beam localization method allowed conclusions regarding the effects of blood flow to be drawn from previously inconclusive (because of localization uncertainties) data. Comparison of the position-adjusted transient temperature profiles for flow rates of 0 and 400ml/min showed that blood flow can reduce temperature elevations by more than 10%, when the HIFU focus is within a 2mm distance from the vessel wall. At acoustic power levels of 17.3 and 24.8W there is a 20- to 70-fold decrease in thermal dose due to the convective cooling effect of blood flow, implying a shrinkage in lesion size. The beam-localization technique also revealed the level of thermocouple artifact as a function of sonication time, providing investigators with an indication of the quality of thermocouple data for a given exposure time. The maximum artifact was found to be double the measured temperature rise, during initial few seconds of sonication.

  16. Mathematical Models and Numerical Simulations for the Blood Flow in Large Vessels

    Directory of Open Access Journals (Sweden)

    Titus PETRILA

    2012-12-01

    Full Text Available We are proposing a non-Newtonian, Cross type rheological model for the blood flow, under the conditions of an unsteady flow regime connected with the rhythmic pumping of the blood by the heart. We admit the incompressibility and homogeneity of the blood while its flow is laminar and the exterior body forces are neglected. We take also into account the viscoelastic behavior of the vessel walls. The mathematical equations and the appropriate boundary conditions are considered in cylindrical (axisymmetric coordinates. Numerical experiments in case of stenosed artery and in artery with aneurysm (using COMSOL Multiphysics 3.3 are made. The variation of the wall shear stress, which is believed to have a special importance in the rupture of aneurysms, is calculated using both a Newtonian and a non-Newtonian model.

  17. Postoperative osteomyelitis following implant arthroplasty of the foot: diagnosis with indium-111 white blood cell scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Bakst, R.H.; Kanat, I.O.

    1987-11-01

    Many complications can occur following insertion of silicone elastomer implants into the foot. Postoperative infection may be difficult to distinguish from other conditions such as dislodgment, fracture, ectopic and heterotopic new bone formation, synovitis, and bursitis. White blood cell scintigraphy, in conjunction with the clinical scenario, may prove to be an invaluable tool in the diagnosis of postoperative osteomyelitis, subsequent to implant arthroplasties. 32 references.

  18. Comparison of the number of gingival blood vessels between type 2 diabetes mellitus and chronic periodontitis patients: An immunohistological study

    OpenAIRE

    Gautami Subhadra Penmetsa; Satyanarayana Baddam; Ravikanth Manyam; Chinni Doraswamy Dwarakanath

    2015-01-01

    Background: The relationship between diabetes and periodontitis has been studied for more than 50 years and is generally agreed that the periodontal disease is more prevalent in diabetic patients compared to nondiabetics. Vascular changes like increased thickness of basement membrane in small vessels has been reported in diabetic patients, but the quantity of blood vessels in gingiva of diabetic patients has not been discussed much. The aim of this study was to compare the number of blood ves...

  19. [Case report with multiple variations of blood vessels originating from the fossa axillaris].

    Science.gov (United States)

    Papanchev, V; Krustev, D; Krustev, N

    2003-01-01

    In the course of a dissection of a male's cadaver, fixed in formol carbol solution, we identified the following arterial variations: A) Regio axillaris dextra: a musculi teretis major (9 cm long); a. musculi subscapularis (of insignificant calibre and length); a. thoracica lateralis accessoria prima (10 cm long, with a course along the surface of m. subscapularis); a. thoracica lateralis accessoria secunda (25 cm long, with a course within the conjunctive tissue of the axilla); B) Regio axillaris sinistra: a musculi subcapularis prima et secunda (of insignificant calibre and length); a. musculi teretis major (9 cm long); a. thoracica lateralis accessoria secunda (20 cm long); a. thoracica lateralis accessoria tertia (25 cm long); All three additional arteria had a course along the surface of m. serratis anterior. We called the identified vessels after the name of the muscle blood-supplied by them. Only the vessels ending in m. serratus anterior did we call aa. thoracicae laterales accessoriae.

  20. Application of a modified regularization procedure for estimating oxygen tension in large retinal blood vessels

    Science.gov (United States)

    Yildirim, Isa; Ansari, Rashid; Samil Yetik, I.; Shahidi, Mahnaz

    2010-03-01

    Phosphorescence lifetime measurement based on a frequency domain approach is used to estimate oxygen tension in large retinal blood vessels. The classical least squares (LS) estimation was initially used to determine oxygen tension indirectly from intermediate variables. A spatial regularized least squares (RLS) method was later proposed to reduce the high variance of oxygen tension estimated by LS method. In this paper, we provide a solution using a modified RLS (MRLS) approach that utilizes prior knowledge about retinal vessels oxygenation based on expected oxygen tension values in retinal arteries and veins. The performance of MRLS method was evaluated in simulated and experimental data by determining the bias, variance, and mean absolute error (MAE) of oxygen tension measurements and comparing these parameters with those derived with the use of LS and RLS methods.

  1. [Molecular mechanism for the establishment of blood-vessel gateway for immune cells in the CNS.

    Science.gov (United States)

    Murakami, Masaaki

    2017-01-01

    We have been studying about the molecular mechanism responsible for the establishment of the blood-vessel gateway through which immune cells enter the CNS. We have discovered three kinds of gateways in a multiple sclerosis model, EAE, based on the neural stimulations and named them the gravity-gateway reflex, electric-gateway reflex, and pain-gateway reflex, respectively. All gateway reflexes are involved in specific crosstalk between sensory-sympathetic pathways. For example, in the gravity-gateway reflex, gravity-mediated sensory stimulation via the soleus muscles activates fifth lumber(L5)dorsal loot ganglions to activate L5 sympathetic ganglions, which express norepinephrine at specific vessels of the L5 cord. We explain these three types of gateway reflexes in this chapter.

  2. Understanding How Space Travel Affects Blood Vessels: Arterial Remodeling and Functional Adaptations Induced by Microgravity

    Science.gov (United States)

    Delp, Michael; Vasques, Marilyn; Aquilina, Rudy (Technical Monitor)

    2002-01-01

    Ever rise quickly from the couch to get something from the kitchen and suddenly feel dizzy? With a low heart rate and relaxed muscles, the cardiovascular system does not immediately provide the resistance necessary to keep enough blood going to your head. Gravity wins, at least for a short time, before your heart and blood vessels can respond to the sudden change in position and correct the situation. Actually, the human cardiovascular system is quite well adapted to the constant gravitational force of the Earth. When standing, vessels in the legs constrict to prevent blood from collecting in the lower extremities. In the space environment, the usual head-to-foot blood pressure and tissue fluid gradients that exist during the upright posture on Earth are removed. The subsequent shift in fluids from the lower to the upper portions of the body triggers adaptations within the cardiovascular system to accommodate the new pressure and fluid gradients. In animal models that simulate microgravity, the vessels in the head become more robust while those in the lower limbs become thin and lax. Similar changes may also occur in humans during spaceflight and while these adaptations are appropriate for a microgravity environment, they can cause problems when the astronauts return to Earth or perhaps another planet. Astronauts often develop orthostatic intolerance which means they become dizzy or faint when standing upright. This dizziness can persist for a number of days making routine activities difficult. In an effort to understand the physiological details of these cardiovascular adaptations, Dr. Michael Delp at Texas A&M University, uses the rat as a model for his studies. For the experiment flown on STS-107, he will test the hypothesis that blood vessels in the rats' hindlimbs become thinner, weaker, and constrict less in response to pressure changes and to chemical signals when exposed to microgravity. In addition, he will test the hypothesis that arteries in the brain

  3. Beta-adrenoceptor-mediated vasodilation of retinal blood vessels is reduced in streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Nakazawa, Taisuke; Sato, Ayumi; Mori, Asami; Saito, Maki; Sakamoto, Kenji; Nakahara, Tsutomu; Ishii, Kunio

    2008-01-01

    We investigated the effects of epinephrine and dopamine on retinal blood vessels in streptozotocin (STZ, 80 mg/kg, i.p.)-treated rats and age-matched control rats to determine whether diabetes mellitus alters the retinal vascular responses to circulating catecholamines. Experiments were performed 6-8 weeks after treatment with STZ or the vehicle. The fundus images were captured with the digital fundus camera system for small animals we developed and diameters of retinal blood vessels contained in the digital images were measured. Epinephrine increased the diameters of retinal blood vessels, but the vasodilator responses were reduced in diabetic rats. Dopamine produced a biphasic retinal vascular response with an initial vasoconstriction followed by a vasodilation. The vasoconstrictor effects of dopamine on retinal arterioles were enhanced in diabetic rats, whereas the difference between the two groups was abolished by treatment with propranolol. The vasodilator effect of isoproterenol, but not of the activator of adenylyl cyclase colforsin, on retinal blood vessels was reduced in diabetic rats. No difference in vasoconstriction of retinal blood vessels to phenylephrine between non-diabetic and diabetic rats was observed. The vasodilator responses of retinal blood vessels to 1,1-dimethyl-4-phenylpiperazinium, a ganglionic nicotinic receptor agonist, were also attenuated in diabetic rats. These results suggest that diabetes mellitus alters the retinal vascular responses to circulating catecholamines and the impairment of vasodilator responses mediated by beta-adrenoceptors contributes to the alteration.

  4. Bioprinting of artificial blood vessels: current approaches towards a demanding goal.

    Science.gov (United States)

    Hoch, Eva; Tovar, Günter E M; Borchers, Kirsten

    2014-11-01

    Free-form fabrication techniques, often referred to as '3D printing', are currently tested with regard to the processing of biological and biocompatible materials in general and for fabrication of vessel-like structures in particular. Such computer-controlled methods assemble 3D objects by layer-wise deposition or layer-wise cross-linking of materials. They use, for example, nozzle-based deposition of hydrogels and cells, drop-on-demand inkjet-printing of cell suspensions with subsequent cross-linking, layer-by-layer cross-linking of synthetic or biological polymers by selective irradiation with light and even laser-induced deposition of single cells. The need of vessel-like structures has become increasingly crucial for the supply of encapsulated cells for 3D tissue engineering, or even with regard to future application such as vascular grafts. The anticipated potential of providing tubes with tailored branching geometries made of biocompatible or biological materials pushes future visions of patient-specific vascularized tissue substitutions, tissue-engineered blood vessels and bio-based vascular grafts. We review here the early attempts of bringing together innovative free-form manufacturing processes with bio-based and biodegradable materials. The presented studies provide many important proofs of concepts such as the possibility to integrate viable cells into computer-controlled processes and the feasibility of supplying cells in a hydrogel matrix by generation of a network of perfused channels. Several impressive results in the generation of complex shapes and high-aspect-ratio tubular structures demonstrate the potential of additive assembly methods. Yet, it also becomes obvious that there remain major challenges to simultaneously match all material requirements in terms of biological functions (cell function supporting properties), physicochemical functions (mechanical properties of the printed material) and process-related (viscosity, cross

  5. A new design and computational fluid dynamics study of an implantable axial blood pump.

    Science.gov (United States)

    Koochaki, Mojtaba; Niroomand-Oscuii, Hanieh

    2013-12-01

    Considering small thoracic space, using implantable ventricular assist device requires reduction in a pump size. Among many available blood pumps, axial blood pumps have attracted greatly because of their small size. In this article, a new miniature axial blood pump has been designed and studied which can be easily implanted in the human body. In this design, the pump overall length decreased by a little increasing in the pump diameter, and new blade geometry is used to produce a streamlined, idealized, and nonobstructing blood flow path in the pump. By means of computational fluid dynamic, the flow pattern through the pump has been predicted and overall pump performance and efficiency has been computed. Also, to ensure a reliable VAD design, two methods for checking wall shear stress were used to confirm that this pump wouldn't cause serious blood damage.

  6. In Silico Magnetic Nanocontainers Navigation in Blood Vessels: A Feedback Control Approach.

    Science.gov (United States)

    Do, Ton Duc; Noh, Yeongil; Kim, Myeong Ok; Yoon, Jungwon

    2016-06-01

    Magnetic nanoparticles (MNPs) are recently used in a drug delivery system to pass the blood brain barrier. However, because the magnetic force acting on particles is proportional to their volumes, as the size of particles is small, the large magnetic field is required to produce enough magnetic force for overcoming the hydrodynamic drag force as well as other forces in blood vessels. Other difficulties for controlling MNPs are the complicated behavior of hydrodynamic drag force and uncertain factors in their dynamics. Therefore, open-loop control methods cannot guarantee guiding every MNP to the correct location. Considering these challenges, this paper introduces a feedback control approach for magnetic nanoparticles (MNPs) in blood vessels. To the best of our knowledge, this is the first time feedback controller that is designed for MNPs without aggregation. Simulation studies in MATLAB and real-time verifications on a physical model in COMSOL-MATLAB interface are performed to prove the feasibility of the proposed approach. It is shown that the proposed control scheme can accurately and effectively navigate the MNP to the correct path with feasible hardware supports.

  7. Correlation mapping method of OCT for visualization blood vessels in brain

    Science.gov (United States)

    Izotova, O. A.; Kalyanov, A. L.; Lychagov, V. V.; Semyachkina-Glushkovskaya, O. V.

    2013-11-01

    The burning issue in modern medicine is the diagnosis and treatment of various life-threatening diseases, in particular the diseases of brain. One of them is intracranial hemorrhage (ICH). It occurs especially among newborn babies and is hard-diagnosed. In order to understand the nature of the ICH, the microcirculation of blood, which serves key functions within the body, is analyzed. On this basis a series of experiments was done, in the results of which it was showed, that latent stage of ICH is characterized by decrease of venous blood outflow and the loss of sensitivity of sagittal vein to vasoconstrictor effect of adrenaline. So, stress-related changes of the cerebral venous blood flow (CVBF) can be the source of this disease. In this paper registration CVBF was made with the help of commercially available Thorlabs Swept Source OCT System, using the correlation mapping method. In this method values of correlation coefficient of several images are analyzed. In the result of the algorithm the correlation map was obtained. By the resulting map the diameter of vessels was calculated, which is necessary for examination of effects of adrenalin to the vessels and identification symptoms of ICH.

  8. Effects of Scopolamine on Blood Vessels in Rabbit Ear after Sympathetic and Sensory Denervation

    Institute of Scientific and Technical Information of China (English)

    刘书勤; 臧伟进; 成亮; 李增利; 于晓江; 李宝平

    2004-01-01

    Objectives To investigate the effects and involved mechanisms of scopolamine (Scop) on rabbit ear blood vessels. Methods Rabbit ear blood vessels were desympathetic and desensory innervation with surgical operation. Diameters of dorsal auricular arterial trunks in vivo were measured with a pair of compasses and the ruler in a dissecting microscope, and effluents from isolated ear under constant perfusion pressure were recorded with a digital drop-recorder. Results Intramuscular injection of Scop 0.1 mg/kg made the diameter of denerved dorsal auricular arterial trunks, as well as that of innerved ones, significantly increased. Scop by itself, at the maximal concentration (Cmax) of 3 μM, 30 μM and 300 μM, did not alter the effluent flow from the isolated denervated rabbit ear, but chlorpromazine (CPZ), at Cmax of 1 μM, acetylcholine (ACh), 0.25μM, all significantly increased the effluent flow, and norepinephrine (NE), 0.1μM, significantly decreased the effluent. Scop, 3 μM, did not affect ACh (0.25μM)-induced the increase of effluent flow, but Scop,30μM, alleviated the increase. Scop, 3μM, did not affect NE (0.1 μM)-induced the decrease of effluent flow, but Scop, 10, 30 and 100 μM, significantly alleviated the decrease. Conclusions The study suggests that Scop has no direct vasodilator effect. The vasodilator effect of Scop is not due to the blockade of muscarinic receptor. However, Scop can dilate blood vessels contracted by α1-adrenoceptor activation.

  9. Architecture of the subendothelial elastic fibers of small blood vessels and variations in vascular type and size.

    Science.gov (United States)

    Shinaoka, Akira; Momota, Ryusuke; Shiratsuchi, Eri; Kosaka, Mitsuko; Kumagishi, Kanae; Nakahara, Ryuichi; Naito, Ichiro; Ohtsuka, Aiji

    2013-04-01

    Most blood vessels contain elastin that provides the vessels with the resilience and flexibility necessary to control hemodynamics. Pathophysiological hemodynamic changes affect the remodeling of elastic components, but little is known about their structural properties. The present study was designed to elucidate, in detail, the three-dimensional (3D) architecture of delicate elastic fibers in small vessels, and to reveal their architectural pattern in a rat model. The fine vascular elastic components were observed by a newly developed scanning electron microscopy technique using a formic acid digestion with vascular casts. This method successfully visualized the 3D architecture of elastic fibers in small blood vessels, even arterioles and venules. The subendothelial elastic fibers in such small vessels assemble into a sheet of meshwork running longitudinally, while larger vessels have a higher density of mesh and thicker mesh fibers. The quantitative analysis revealed that arterioles had a wider range of mesh density than venules; the ratio of density to vessel size was higher than that in venules. The new method was useful for evaluating the subendothelial elastic fibers of small vessels and for demonstrating differences in the architecture of different types of vessels.

  10. Effect of Rolling Massage on Particle Moving Behaviour in Blood Vessels

    Institute of Scientific and Technical Information of China (English)

    YI Hou-Hui; FAN Li-Juan; YANG Xiao-Feng; CHEN Yan-Yan

    2008-01-01

    The rolling massage manipulation is a classic Chinese massage, which is expected to eliminate many diseases.Here the effect of the rolling massage on the particle moving property in the blood vessels under the rolling massage manipulation is studied by the lattice Boltzmann simulation. The simulation results show that the particle moving behaviour depends on the rolling velocity, the distance between particle position and rolling position. The average values, including particle translational velocity and angular velocity, increase as the rolling velocity increases almost linearly. The result is helpful to understand the mechanism of the massage and develop the rolling techniques.

  11. THE STEADY/PULSATILE FLOW AND MACROMOLECULAR TRANSPORT IN T-BIFURCATION BLOOD VESSELS

    Institute of Scientific and Technical Information of China (English)

    李丁; 温功碧

    2003-01-01

    A numerical analysis of the steady and pulsatile, macromolecular( such as lowdensity lipopotein ( LDL ), Albumin ) transport in T-bifurcation was proposed. Theinfluence of Reynolds number and mass flow ratio etc. parameters on the velocity field andmass transport were calculated. The computational results predict that the blood flow factorsaffect the macromolecular distribution and the transport across the wall, it shows thathemodynamic play an important role in the process of atherosclerosis . The LDL and Albuminconcentration on the wall varies most greatly in flow bifurcation area where the wall shearstress varies greatly at the branching vessel and the atherosclerosis often appears there.

  12. A Pulsatile Flow Phantom for Image-Guided HIFU Hemostasis of Blood Vessels

    Science.gov (United States)

    Greaby, Robyn; Vaezy, Shahram

    2005-03-01

    A pulsatile flow phantom for studying ultrasound image-guided acoustic hemostasis in a controlled environment has been developed. An ex vivo porcine carotid artery was attached to the phantom and embedded in a visually and ultrasonically transparent gel. Heparinized porcine blood was pumped through the phantom. Power-Doppler and B-mode ultrasound were used to remotely target the HIFU focus to the site of a needle puncture. In nine trials, complete hemostasis was achieved after an average HIFU application of 55 +/- 34 seconds. The vessels remained patent after treatment. With this phantom, it will be possible to do controlled studies of ultrasound image-guided acoustic hemostasis.

  13. 3-D segmentation of retinal blood vessels in spectral-domain OCT volumes of the optic nerve head

    Science.gov (United States)

    Lee, Kyungmoo; Abràmoff, Michael D.; Niemeijer, Meindert; Garvin, Mona K.; Sonka, Milan

    2010-03-01

    Segmentation of retinal blood vessels can provide important information for detecting and tracking retinal vascular diseases including diabetic retinopathy, arterial hypertension, arteriosclerosis and retinopathy of prematurity (ROP). Many studies on 2-D segmentation of retinal blood vessels from a variety of medical images have been performed. However, 3-D segmentation of retinal blood vessels from spectral-domain optical coherence tomography (OCT) volumes, which is capable of providing geometrically accurate vessel models, to the best of our knowledge, has not been previously studied. The purpose of this study is to develop and evaluate a method that can automatically detect 3-D retinal blood vessels from spectral-domain OCT scans centered on the optic nerve head (ONH). The proposed method utilized a fast multiscale 3-D graph search to segment retinal surfaces as well as a triangular mesh-based 3-D graph search to detect retinal blood vessels. An experiment on 30 ONH-centered OCT scans (15 right eye scans and 15 left eye scans) from 15 subjects was performed, and the mean unsigned error in 3-D of the computer segmentations compared with the independent standard obtained from a retinal specialist was 3.4 +/- 2.5 voxels (0.10 +/- 0.07 mm).

  14. Gingival aesthetics of the maxilary anterior tooth implant prosthesis%上颌前牙种植修复中牙龈美学的探讨

    Institute of Scientific and Technical Information of China (English)

    朱启红; 张小云; 杨新亮

    2013-01-01

    目的:探讨上颌前牙单牙种植修复中牙龈美学的美学效果。方法29例上颌前牙单牙种植采用引导骨再生术,准确的种植三维位点,正确的软组织切口,软组织引导,乳头重建技术,临时冠诱导软组织成型,个性化全瓷基台全瓷冠修复或义龈修复等进行美学修复。采用完美美学效果,患者满意度VAS进行美学效果评价。结果29例上颌前牙单牙种植修复,12月后种植体的成功率为100%;完美美学效果9例,美学效果较满意20例,美学效果很差0例;患者满意度VAS最低6分,最高10分,平均值8.56分。结论根据自身条件,采用引导骨再生术,准确的种植三维位点,正确的软组织切口,软组织引导,乳头重建技术,临时冠诱导软组织成型,个性化全瓷基台全瓷冠修复或义龈修复等进行美学修复能满足患者牙龈的美学要求。%Objective: The aim of this study was to investigate the gingival aesthetic effect of the maxilary anterior single tooth implant prosthesis. Methods: 29 maxilary anterior single tooth implant prostheses were aestheticaly repaired with guided bone regeneration technique, accurate three-dimensional loci of planting, the correct parenchyma incision, soft-tissue-guiding, nipple reconstruction technology, temporary crowns induced soft tissue forming, personalized al-ceramic crown repair with al-ceramic base stations or gum repair. The aesthetic effect was evaluated with perfect aesthetic effect and Patient satisfaction VAS.Results: The success rate was 100% after 12 months of these 29 cases of maxilary anterior single tooth implant prostheses, among which 9 cases were of perfect aesthetic effect, 20 cases were satisfied with aesthetic effect and 0 case was very poor aesthetic effect. Evaluated with Patient satisfaction VAS, the result was minimum 6 points, maximum 10 points and the average of 8.56 points.Conclusion: According to their own conditions, comprehensive

  15. Synchronization of endothelial Dll4-Notch dynamics switch blood vessels from branching to expansion

    Science.gov (United States)

    Ubezio, Benedetta; Blanco, Raquel Agudo; Geudens, Ilse; Stanchi, Fabio; Mathivet, Thomas; Jones, Martin L; Ragab, Anan; Bentley, Katie; Gerhardt, Holger

    2016-01-01

    Formation of a regularly branched blood vessel network is crucial in development and physiology. Here we show that the expression of the Notch ligand Dll4 fluctuates in individual endothelial cells within sprouting vessels in the mouse retina in vivo and in correlation with dynamic cell movement in mouse embryonic stem cell-derived sprouting assays. We also find that sprout elongation and branching associates with a highly differential phase pattern of Dll4 between endothelial cells. Stimulation with pathologically high levels of Vegf, or overexpression of Dll4, leads to Notch dependent synchronization of Dll4 fluctuations within clusters, both in vitro and in vivo. Our results demonstrate that the Vegf-Dll4/Notch feedback system normally operates to generate heterogeneity between endothelial cells driving branching, whilst synchronization drives vessel expansion. We propose that this sensitive phase transition in the behaviour of the Vegf-Dll4/Notch feedback loop underlies the morphogen function of Vegfa in vascular patterning. DOI: http://dx.doi.org/10.7554/eLife.12167.001 PMID:27074663

  16. Peripheral white blood cells profile of biodegradable metal implant in mice animal model

    Energy Technology Data Exchange (ETDEWEB)

    Paramitha, Devi; Noviana, Deni, E-mail: deni@ipb.ac.id; Estuningsih, Sri [Faculty of Veterinary Medicine, Bogor Agricultural University (IPB), Bogor (Indonesia); Ulum, Mokhamad Fakhrul [Faculty of Veterinary Medicine, Bogor Agricultural University (IPB), Bogor (Indonesia); Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru (Malaysia); Nasution, Ahmad Kafrawi [Faculty of Biosciences and Medical Engineering, Universiti Teknologi Malaysia (UTM), Johor Bahru (Malaysia); Faculty of Engineering, Muhammadiyah University of Riau (UMRI), Pekanbaru (Indonesia); Hermawan, Hendra [Department of Mining, Metallurgical and Materials Engineering & CHU de Québec Research Center, Laval University (ULaval) (Canada)

    2015-09-30

    Biocompatibility or safety of the medical device is considered important. It can be determined by blood profile examination. The aim of this study was to assess the biocompatibility of biodegradable metal implant through peripheral white blood cells (WBCs) profile approach. Forty eight male ddy mice were divided into four groups according to the materials implanted: iron wire (Fe), magnesium rod (Mg), stainless steel surgical wire (SS316L) and control with sham (K). Implants were inserted and attached onto the right femoral bone on latero-medial region. In this study, peripheral white blood cells and leukocyte differentiation were the parameters examined. The result showed that the WBCs value of all groups were decreased at the first day after implantation, increased at the 10th day and continued increasing at the 30th day of observation, except Mg group which has decreased. Neutrophil, as an inflammatory cells, was increased at the early weeks and decreased at the day-30 after surgery in all groups. Despite, these values during the observation were still within the normal range. As a conclus ion, biodegradable metal implants lead to an inflammatory reaction, with no adverse effect on WBC value found.

  17. Prosthesis fabrication using electrical discharge machining.

    Science.gov (United States)

    Van Roekel, N B

    1992-01-01

    Fixed-removable implant prostheses provide solutions for some of the problems associated with implant dentistry, especially in the maxilla. The technique for using electrical discharge machining to create a precise passive fit between the substructure bar and the removable suprastructure is presented. The advantages, disadvantages, and complications associated with this type of prosthesis are discussed.

  18. Imaging transient blood vessel fusion events in zebrafish by correlative volume electron microscopy.

    Directory of Open Access Journals (Sweden)

    Hannah E J Armer

    Full Text Available The study of biological processes has become increasingly reliant on obtaining high-resolution spatial and temporal data through imaging techniques. As researchers demand molecular resolution of cellular events in the context of whole organisms, correlation of non-invasive live-organism imaging with electron microscopy in complex three-dimensional samples becomes critical. The developing blood vessels of vertebrates form a highly complex network which cannot be imaged at high resolution using traditional methods. Here we show that the point of fusion between growing blood vessels of transgenic zebrafish, identified in live confocal microscopy, can subsequently be traced through the structure of the organism using Focused Ion Beam/Scanning Electron Microscopy (FIB/SEM and Serial Block Face/Scanning Electron Microscopy (SBF/SEM. The resulting data give unprecedented microanatomical detail of the zebrafish and, for the first time, allow visualization of the ultrastructure of a time-limited biological event within the context of a whole organism.

  19. A composite chitosan-gelatin bi-layered, biomimetic macroporous scaffold for blood vessel tissue engineering.

    Science.gov (United States)

    Badhe, Ravindra V; Bijukumar, Divya; Chejara, Dharmesh R; Mabrouk, Mostafa; Choonara, Yahya E; Kumar, Pradeep; du Toit, Lisa C; Kondiah, Pierre P D; Pillay, Viness

    2017-02-10

    A composite chitosan-gelatin macroporous hydrogel-based scaffold with bi-layered tubular architecture was engineered by solvent casting-co-particulate leaching. The scaffold constituted an inner macroporous layer concealed by a non-porous outer layer mimicking the 3D matrix of blood vessels with cellular adhesion and proliferation. The scaffold was evaluated for its morphological, physicochemical, physicomechanical and biodurability properties employing SEM, FTIR, DSC, XRD, porositometry, rheology and texture analysis. The fluid uptake and biodegradation in the presence of lysozymes was also investigated. Cellular attachment and proliferation was analysed using human dermal fibroblasts (HDF-a) seeded onto the scaffold and evaluated by MTT assay, SEM, and confocal microscopy. Results demonstrated that the scaffold had a desirable tensile strength=95.81±11kPa, elongation at break 112.5±13%, porosity 82% and pores between 100 and 230μm, 50% in vitro biodegradation at day 16 and proliferated fibroblasts over 20 days. These results demonstrate that scaffold may be an excellent tubular archetype for blood vessel tissue engineering.

  20. Protective role of a novel human erythrocyte-derived depressing factor on blood vessels in rats

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The protective role of a human erythrocyte-derived depressing factor (EDDF) on blood vessels was evaluated. The experiments were carried out on 25male Wistar rats aged 6-8 weeks, which were divided into control (n = 8), calcium overload (n = 8) and NG-L-nitro-arginine hypertensive model groups (L-NNA,n = 9), respectively. The isolated vascular ring perfusion assay, two-photon laser scanning fluorescence microscopy (TPM) and transmitted electron microscope were used to examine the effect of EDDF on vascular function and ultrastructure. Results showed that the contractile response of calcium overload rats and L-NNA rats to phenylephrine (PE) was significantly enhanced compared with that of the control (P < 0.05), and EDDF (10-3 g @mL-1) remarkably decreased the vascular contractile response of control's and calcium overload rats (P < 0.05),while EDDF had no effect on that of L-NNA rats. EDDF also alleviated the ultrastructural lesion of aorta VSMC in calcium overload rats by easing the abnormal in the nucleus, mitochondrion and other organell. It is concluded that EDDF could efficiently protect blood vessels against injury by influencing Ca2+ transport and ameliorating the lesion of VSMC, and further supported the hypothesis that the NO-cGMP pathway might contribute to the vasodilation and partially antihypertensive mechanism of EDDF.``

  1. An Original Approach for Quantification of Blood Vessels on the Whole Tumour Section

    Directory of Open Access Journals (Sweden)

    Nga Tran Kim

    2003-01-01

    Full Text Available Relative abundance of tumour angiogenesis has been shown to be of clinical relevance in cancers of various locations such as the ovary. Nevertheless, several problems are encountered when quantifying tumour microvessels: (i as many other tumour markers, vascularity pattern is often heterogeneous within the tumour mass and even within the same histological section. As a consequence, an adequate acquisition method must be developed for accurate field sampling. (ii Manual microvessel counting is long, tedious and subject to poor reproducibility. Introduction in routine practice requires a fast, reproducible and reliable automatic image processing. In this study we present an original procedure combining a slide scanner image acquisition and a fully automatic image analysis sequence. The slide scanner offers the advantage of recording an image of the whole histological section for subsequent automatic blood vessel detection and hot spot area location. Microvessel density and surface fraction were measured for the whole section as well as within hot spots. Different immunostaining methods were tested in order to optimise the procedure. Moreover, the method proposed was submitted to a quality control procedure, with reference to interactive identification of microvessels at scanner level. This experiment showed that 93 to 97% of blood vessels were detected, according to the staining protocol used. Colour figures can be viewed on http://www.esacp.org/acp/2003/25‐2/kim.htm.

  2. Low cost labeling with highlighter ink efficiently visualizes developing blood vessels in avian and mouse embryos.

    Science.gov (United States)

    Takase, Yuta; Tadokoro, Ryosuke; Takahashi, Yoshiko

    2013-12-01

    To understand how blood vessels form to establish the intricate network during vertebrate development, it is helpful if one can visualize the vasculature in embryos. We here describe a novel labeling method using highlighter ink, easily obtained in stationery stores with a low cost, to visualize embryo-wide vasculatures in avian and mice. We tested 50 different highlighters for fluorescent microscopy with filter sets equipped in a standard fluorescent microscope. The yellow and violet inks yielded fluorescent signals specifically detected by the filters used for green fluorescent protein (GFP) and red fluorescent protein (RFP) detections, respectively. When the ink solution was infused into chicken/quail and mouse embryos, vasculatures including large vessels and capillaries were labeled both in living and fixed embryos. Ink-infused embryos were further subjected to histological sections, and double stained with antibodies including QH-1 (quail), α smooth muscle actin (αSMA), and PECAM-1 (mouse), revealing that the endothelial cells were specifically labeled by the infused highlighter ink. Highlighter-labeled signals were detected with a resolution comparable to or higher than signals of fluorescein isothiocyanate (FITC)-lectin and Rhodamine-dextran, conventionally used for angiography. Furthermore, macroconfocal microscopic analyses with ink-infused embryos visualized fine vascular structures of both embryo proper and extra-embryonic plexus in a Z-stack image of 2400 μm thick with a markedly high resolution. Together, the low cost highlighter ink serves as an alternative reagent useful for visualization of blood vessels in developing avian and mouse embryos and possibly in other animals.

  3. The effect of complex exercise rehabilitation program on body composition, blood pressure, blood sugar, and vessel elasticity in elderly women with obesity

    Science.gov (United States)

    Lee, Eun-Ok; Lee, Kwon-Ho; Kozyreva, Olga

    2013-01-01

    The purpose of this study is to identify what kind of effects complex exercise rehabilitation program has on body composition of female, blood pressure, blood sugar, blood vessel elasticity and find more effective complex exercise program for elderly females. The subjects are selected 30 females applicants in exercise program in City of G and not restricted in mobility to perform the exercise without any particular disorders. Exercise program is a combination of aerobic and strength training with different ratio, for the first 6 months focused on strength training complex exercise, and for next 6 months focused on aerobic exercise. Except for strength training and aerobic exercise, durations for strength, rest, and wrapping-up are equal. The frequency of experiments is 90 min each, 2 times per a week. Body composition, blood pressure, and blood vessel elasticity are tested pre and post experiment to compare the effectiveness of both complex exercises. As results, in the complex exercise program focused on strength training, weight, percent body fat, fat mass, waist hip ratio, systolic blood pressure, and diastolic pressure increased. Blood vessel elasticity maintained its level or slightly decreased. In the complex exercise focused on aerobic exercise, weight, percent body fat, fat mass, waist hip ratio, systolic pressure, and diastolic pressure decreased. Blood vessel elasticity on left foot and right foot are slightly different. Therefore, aerobic exercise is more effective than strength training for old obese females. PMID:24409428

  4. Successful Implantation of a Coronary Stent Graft in a Peripheral Vessel

    Directory of Open Access Journals (Sweden)

    Alexander Hess

    2015-01-01

    Full Text Available Peripheral artery disease (PAD is a complex, often underdiagnosed illness with rising prevalence in western world countries. During the past decade there has been a rapid advance especially in the field of endovascular treatment of PAD. Here we present for the first time a case reporting on the placement of coronary stent graft in a peripheral vessel for the management of a peripheral side branch perforation. Interventional angiologists or radiologists may consider such an option for complication management after injury of smaller vessels during peripheral percutaneous interventions. Further specialization and novel options of complication management as described in our case may shift the treatment from surgical to even more endovascular treatment procedures in the future.

  5. [The treatment of abdominal aortic aneurysms by use of endovascular prosthesis and classic vascular prosthesis].

    Science.gov (United States)

    Pupka, Artur; Szyber, Przemysław P; Janczak, Dariusz; Pawłowski, Stanisław; Szyber, Piotr

    2006-01-01

    The abdominal aortic aneurysm is a dilatation of infrarenal part of aorta. Its ethiology is still unknown. An infection and congenital disorders of conjunctive tissue are regarded as the main risc factors. Other factors could be a perimural thrombus and elastin and colagen degradation. It's not proved that atheromatosis is a risc factor. The disease concerns mainly the old males. Not treated aneurysm grows until rupture. The aneurysms are usually asympthomatic. Majority of them are found incidentally. Ultrasonography and computed tomography are used to extended diagnosis. The open surgery or endovascular surgery are only possible ways of treatment. The aneurysm with diameter over 55 milimeters, sympthomatic or rupted is an indication for surgery. The aim of the open surgery is implantation of the vascular prosthesis into retroperitoneal space. Endovascular method consist in placement of stent-graft in the lumen of aneurysm through small incision in a peripherial vessel. Stent-graft consists of metal chassis covered by classic vascular prosthesis. This method still requires the long-term assessment.

  6. 3D Computer Simulations of Pulsatile Human Blood Flows in Vessels and in the Aortic Arch: Investigation of Non-Newtonian Characteristics of Human Blood

    CERN Document Server

    Sultanov, Renat A; Engelbrekt, Brent; Blankenbecler, Richard

    2008-01-01

    Methods of Computational Fluid Dynamics are applied to simulate pulsatile blood flow in human vessels and in the aortic arch. The non-Newtonian behaviour of the human blood is investigated in simple vessels of actual size. A detailed time-dependent mathematical convergence test has been carried out. The realistic pulsatile flow is used in all simulations. Results of computer simulations of the blood flow in vessels of two different geometries are presented. For pressure, strain rate and velocity component distributions we found significant disagreements between our results obtained with realistic non-Newtonian treatment of human blood and widely used method in literature: a simple Newtonian approximation. A significant increase of the strain rate and, as a result, wall sear stress distribution, is found in the region of the aortic arch. We consider this result as theoretical evidence that supports existing clinical observations and those models not using non-Newtonian treatment underestimate the risk of disru...

  7. Ultrasonic imaging of foreign inclusions and blood vessels through thick skull bones.

    Science.gov (United States)

    Shapoori, Kiyanoosh; Sadler, Jeffrey; Ahmed, Zaki; Wydra, Adrian; Maeva, Elena; Malyarenko, Eugene; Maev, Roman

    2015-03-01

    We report a new progress in the development of a portable ultrasonic transcranial imaging system, which is expected to significantly improve the clinical utility of transcranial diagnostic ultrasound. When conventional ultrasonic phased array and Doppler techniques are applied through thick skull bones, the ultrasound field is attenuated, deflected, and defocused, leading to image distortion. To address these deficiencies, the ultrasonic transcranial imaging system implements two alternative ultrasonic methods. The first method improves detection of small foreign objects, such as bone fragments, pieces of shrapnel, or bullets, lodged in the brain tissue. Using adaptive beamforming, the method compensates for phase aberration induced by the skull and refocuses the distorted ultrasonic field at the desired location. The second method visualizes the blood flow through intact human skull using ultrasonic speckle reflections from the blood cells, platelets, or contrast agents. By analyzing these random temporal changes, it is possible to obtain 2D or 3D blood flow images, despite the adverse influence of the skull. Both methods were implemented on an advanced open platform phased array controller driving linear and matrix array probes. They were tested on realistic skull bone and head phantoms with foreign inclusions and blood vessel models.

  8. A novel microporous polyurethane blood conduit: biocompatibility assessment of the UTA arterial prosthesis by an organo-typic culture technique.

    Science.gov (United States)

    Sigot-Luizard, M F; Sigot, M; Guidoin, R; King, M; von Maltzahn, W W; Kowligi, R; Eberhart, R C

    1993-01-01

    An organotypic culture assay has been used to assess the biocompatibility and cytotoxicity of an arterial prosthesis developed at the University of Texas-Arlington (the UTA graft) from a structurally modified polyurethane (PU) elastomer (Tecoflex). The cell culture test was applied to the UTA graft after sterilization by ethylene oxide and by gamma radiation in two separate series. First, small specimens of the prosthesis were incubated for 7 days on a semisolid nutrient medium with their luminal surface in direct contact with endothelium explanted from the aorta of chick embryos. Second, the possibility of cytotoxic contaminants being leached from the polyurethane was assessed by immersing the biomaterial in the liquid culture medium for 5 days at 37 degrees C prior to conducting the organo-typic culture assay on a standard control surface. The structure of the UTA polyurethane prosthesis is porous, but the graft wall is impervious because it contains closed (i.e., noncommunicating) pores. In addition, four other vascular prostheses were included in the study for comparison. They were the Hydrophilic Mitrathane PU graft with a similar impervious, closed pore structure, an experimental Hydrophobic Mitrathane PU graft with a fibrous, open pore structure, and the commercial Impra and Reinforced Goretex expanded PTFE grafts. Following 7 days of cell culture, the biocompatibility and cytotoxicity of the various biomaterials were measured in terms of the area of migrating cells, the density of cells surrounding the explants, and the level of cell adhesion. Comparison of the results against control cultures demonstrated that the UTA graft, along with the other four prostheses, does not release cytotoxic extractables. Microscopic observations of its cultured surface indicated that the UTA graft promotes a high density of cell growth over a limited area, similar to the Hydrophilic Mitrathane graft. This level of biocompatibility is considered inferior to that of the two

  9. 应用以修复为中心的简易种植模板种植牙159例临床回顾%A review on 159 tooth-implant cases supported by prosthesis-centered simplified implant template

    Institute of Scientific and Technical Information of China (English)

    丁明会; 贾占涛; 夏蕊; 董世涛

    2014-01-01

    Objective To evaluate the clinical efficacy of tooth implant supported by prosthesis-centered simplified implant template. Methods 159 implant cases from 2008 to 2012 were included into this study. All the cases located the implant on template with 2. 0-mm-diam wax string before operation. The template was manufactured with implantation fossa by laying self curing plastic,utilizing the template to guide the operation,observing if the implant is in a correct three-dimensional position by means of x-ray photography after operation,and by observing the position of gingival former on the model during prosthodontic procedure. Results Situation and position of all the 268 implants is fine as expecta-tion. Postoperative follow up and satisfaction survey showed that 156 were satisfied with the prosthesis,2 were satisfied after reprosthesis,1 merely accepted the effect of prosthesis among the 159 patients. Conclusion The prosthesis-centered simplified implant template is effective in guiding implant operation,in view of pinpointing the implant. This method can provide fine reference for later prosthesis,and ensure long-term success ratio. Patients will feel comfortable,be efficient in chewing. The patient would be willing to have the operation. This method will help to promote dental implant.%目的:总结评价以修复为中心的简易种植模板种植牙的临床疗效。方法选取2008~2012年种植科种植修复治疗患者159例,术前在模型上用直径2.0 mm蜡线确定植体位置方向,然后铺自凝塑料制作带有植入道的模板,术中应用模板指导手术,术后通过X线片检查及修复时在模型上观察基台的位置方向以检验种植体的三维位置方向是否合适。结果268枚植体的位置、方向比较理想,均达到术前设计。修复后随访检查并进行满意度调查,159例患者中,156例对修复效果感觉满意,2例重新修复后感觉满意,1例对修复效果

  10. Neutrophil-Mediated Delivery of Therapeutic Nanoparticles across Blood Vessel Barrier for Treatment of Inflammation and Infection.

    Science.gov (United States)

    Chu, Dafeng; Gao, Jin; Wang, Zhenjia

    2015-12-22

    Endothelial cells form a monolayer in lumen of blood vessels presenting a great barrier for delivery of therapeutic nanoparticles (NPs) into extravascular tissues where most diseases occur, such as inflammation disorders and infection. Here, we report a strategy for delivering therapeutic NPs across this blood vessel barrier by nanoparticle in situ hitchhiking activated neutrophils. Using intravital microscopy of TNF-α-induced inflammation of mouse cremaster venules and a mouse model of acute lung inflammation, we demonstrated that intravenously (iv) infused NPs made from denatured bovine serum albumin (BSA) were specifically internalized by activated neutrophils, and subsequently, the neutrophils containing NPs migrated across blood vessels into inflammatory tissues. When neutrophils were depleted using anti-Gr-1 in a mouse, the transport of albumin NPs across blood vessel walls was robustly abolished. Furthermore, it was found that albumin nanoparticle internalization did not affect neutrophil mobility and functions. Administration of drug-loaded albumin NPs markedly mitigated the lung inflammation induced by LPS (lipopolysaccharide) or infection by Pseudomonas aeruginosa. These results demonstrate the use of an albumin nanoparticle platform for in situ targeting of activated neutrophils for delivery of therapeutics across the blood vessel barriers into diseased sites. This study demonstrates our ability to hijack neutrophils to deliver nanoparticles to targeted diseased sites.

  11. Fractals and fractal dimension of systems of blood vessels: An analogy between artery trees, river networks, and urban hierarchies

    CERN Document Server

    Chen, Yanguang

    2015-01-01

    An analogy between the fractal nature of networks of arteries and that of systems of rivers has been drawn in the previous works. However, the deep structure of the hierarchy of blood vessels has not yet been revealed. This paper is devoted to researching the fractals, allometric scaling, and hierarchy of blood vessels. By analogy with Horton-Strahler's laws of river composition, three exponential laws have been put forward. These exponential laws can be reconstructed and transformed into three linear scaling laws, which can be named composition laws of blood vessels network. From these linear scaling laws it follows a set of power laws, including the three-parameter Zipf's law on the rank-size distribution of blood vessel length and the allometric scaling law on the length-diameter relationship of blood vessels in different orders. The models are applied to the observed data on human beings and animals early given by other researchers, and an interesting finding is that human bodies more conform to natural r...

  12. Differentiation of smooth muscle progenitor cells in peripheral blood and its application in tissue engineered blood vessels

    Institute of Scientific and Technical Information of China (English)

    Shang-zhe XIE; Ning-tao FANG; Shui LIU; Ping ZHOU; Yi ZHANG; Song-mei WANG; Hong-yang GAO; Luan-feng PAN

    2008-01-01

    Background: A major shortcoming in tissue engineered blood vessels (TEBVs) is the lack of healthy and easily attainable smooth muscle cells (SMCs). Smooth muscle progenitor cells (SPCs), especially from peripheral blood, may offer an alternative cell source for tissue engineering involving a less invasive harvesting technique. Methods: SPCs were isolated from 5-ml fresh rat peripheral blood by density-gradient centrifugation and cultured for 3 weeks in endothelial growth medium-2-MV (EGM-2-MV) medium containing platelet-derived growth factor-BB (PDGF BB). Before seeded on the synthesized scaffold, SPC-derived smooth muscle outgrowth cell (SOC) phenotypes were assessed by immuno-fluorescent staining, Western blot analysis, and reverse transcription polymerase chain reaction (RT-PCR). The cells were seeded onto the silk fibroin-modified poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (SF-PHBHHx) scaffolds by 6×104 cells/cm'2 and cultured under the static con-dition for 3 weeks. The growth and proliferation of the seeded cells on the scaffold were analyzed by 3-(4,5-dimethylthiazol-2-yl)-diphenyltetrazolium bromide (MTT) assay, scanning electron microscope (SEM), and 4,6-diamidino-2-phenylindole (DAPI) staining. Results: SOCs displayed specific "hill and valley" morphology, expressed the specific markers of the SMC lineage: protein, and extracellular matrix components elastin and matrix Gla protein (MGP), as well as vascular endothelial growth factor (VEGF). After seeded on the SF-PHBHHx scaffold, the cells showed excellent metabolic activity and proliferation. Conclusion: SPCs isolated from peripheral blood can be differentiated into the SMCs in vitro and have an impressive growth potential in the biodegradable synthesized scaffold. Thus, SPCs may be a promising cell source for constructing TEBVs.

  13. Effects of Three Types of Long-acting Contraceptive Implants on Menstrual Blood Loss in 89 Women

    Institute of Scientific and Technical Information of China (English)

    韩丽晖; 范慧民; 龚泉; 谢争; 孟凡; 洪玉凤; 王文娟

    1999-01-01

    Objective: To study the effects of three types of contraceptive implants: the domestic No I , No I implants and Norplant on menstrual blood loss (MBL). Method: Eighty-nine healthy subjects were randomly allocated to three groups.Menstrual blood loss was measured before implanting and 3, 6, and 12 months after implantation. Results: MBL of the three groups prior to the use of implant were 43. 3±6. 9ml,48.9±4. 3 ml, and 43.7±5. 5ml respectively, and decreased significantly at all post-implantation periods. MBLs were 32. 8±13. 2ml, 24. 8±5. 5ml, and 19. 7±9.3ml at the 3rd month after implantation and 23. 9±5. 9 ml, 40. 8±10. 4 ml, 25. 9±6. 0 ml at the 12th month after implantation respectively, sigmficantly less than before implantation(P<0. 05~0. 01). A tendency was seen in increase of hemoglobin concentraition. Conclusion: Long-acting contraceptive implants decreased menstrual blood loss and elevates hemoglobin concentration. They are applicable to women as a contraceptive method without blood loss effects.

  14. Maturation of blood vessels by haematopoietic stem cells and progenitor cells: involvement of apelin/APJ and angiopoietin/Tie2 interactions in vessel caliber size regulation.

    Science.gov (United States)

    Takakura, Nobuyuki; Kidoya, Hiroyasu

    2009-06-01

    Apelin is a recently-isolated bioactive peptide from bovine gastric extract. The gene encodes a protein of 77 amino acids, which can generate two active polypeptides, long (42-77) and short (65-77). Both peptides ligate and activate APJ, a G protein-coupled receptor expressed in the cardiovascular and central nervous systems. Although an essential role for the apelin/APJ system in blood vessel formation has been reported in Xenopus, its precise function in mammals is unclear. Blood vessel tube formation is accomplished by two main mechanisms: 1) single cell hollowing, in which a lumen forms within the cytoplasm of a single endothelial cell (EC), and 2) cord hollowing in which a luminal cavity is created de novo between ECs in a thin cylindrical cord. Molecular control of either single cell or cord hollowing has not been precisely determined. Angiopoietin-1 (Ang1) has been reported to induce enlargement of blood vessels. Apelin is produced from ECs upon activation of Tie2, a cognate receptor of Ang1, expressed on ECs. It has been suggested that apelin induces cord hollowing by promoting proliferation and aggregation/assembly of ECs. During angiogenesis, haematopoietic stem cells (HSCs) and progenitor cells (HPCs) are frequently observed in the perivascular region. They produce Ang1 and induce migration of ECs, resulting in a fine vascular network. Moreover, HSCs/HPCs can induce apelin production from ECs. Therefore, this review article posits that HSCs/HPCs regulate caliber size of blood vessels via apelin/APJ and Angiopoietin/Tie2 interactions.

  15. Distinct mechanisms of relaxation to bioactive components from chamomile species in porcine isolated blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, R.E., E-mail: Richard.roberts@nottingham.ac.uk; Allen, S.; Chang, A.P.Y.; Henderson, H.; Hobson, G.C.; Karania, B.; Morgan, K.N.; Pek, A.S.Y.; Raghvani, K.; Shee, C.Y.; Shikotra, J.; Street, E.; Abbas, Z.; Ellis, K.; Heer, J.K.; Alexander, S.P.H., E-mail: steve.alexander@nottingham.ac.uk

    2013-11-01

    German chamomile (Matricaria recutita L.), a widely-used herbal medicine, has been reported to have a wide range of biological effects, including smooth muscle relaxation. The aim of this study was to compare the effects of representative compounds from chamomile (apigenin, luteolin, (−)-α-bisabolol, farnesene, umbelliferone; 3–30 μM) on vascular tone using porcine coronary and splenic arteries mounted for isometric tension recording in isolated tissue baths and precontracted with the thromboxane-mimetic U46619. Apigenin, luteolin, and (−)-α-bisabolol produced slow, concentration-dependent relaxations in both the coronary and splenic arteries that were not blocked by inhibition of nitric oxide synthase or potassium channels. Removal of extracellular calcium inhibited the relaxations to all three compounds, and these compounds also inhibited calcium re-addition-evoked contractions, indicating that the relaxation response may be mediated through inhibition of calcium influx. Apigenin and luteolin, but not (−)-α-bisabolol, enhanced the relaxation to the nitric oxide donor sodium nitroprusside, indicating that apigenin and luteolin may act to regulate cyclic GMP levels. Umbelliferone produced a rapid, transient relaxation in the splenic artery, but not the coronary artery, that was inhibited by L-NAME and removal of the endothelium, suggesting an influence on nitric oxide production. Farnesene, at concentrations up to 30 μM, was without effect in either blood vessel. In conclusion, hydroxylated compounds (apigenin, luteolin and (−)-α-bisabolol) found in chamomile all caused a slow relaxation of isolated blood vessels through an effect on calcium influx. Umbelliferone, on the other hand, produced a rapid, transient relaxation dependent upon release of nitric oxide from the endothelium. - Highlights: • Apigenin, luteolin, and (-)-α-bisabolol are present in chamomile. • They produced slow, concentration-dependent relaxations in arteries. • These

  16. Multi-detector spiral CT study of the relationships between pulmonary ground-glass nodules and blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Feng; Li, Ming; Ge, Xiaojun; Ren, Qingguo; Hua, Yanqing [Huadong Hospital Fudan University, Department of Radiology, Shanghai (China); Zheng, Xiangpeng [Huadong Hospital Fudan University, Department of Radiation Oncology, Shanghai (China); Chen, Yan [Huadong Hospital Fudan University, Department of Pathology, Shanghai (China); Lv, Fangzhen [Huadong Hospital Fudan University, Department of Thoracic Surgery, Shanghai (China)

    2013-12-15

    To investigate the relationships between pulmonary ground-glass nodules (GGN) and blood vessels and their diagnostic values in differentiating GGNs. Multi-detector spiral CT imaging of 108 GGNs was retrospectively reviewed. The spatial relationships between GGNs and supplying blood vessels were categorized into four types: I, vessels passing by GGNs; II, intact vessels passing through GGNs; III, distorted, dilated or tortuous vessels seen within GGNs; IV, more complicated vasculature other than described above. Relationship types were correlated to pathologic and/or clinical findings of GGNs. Of 108 GGNs, 10 were benign, 24 preinvasive nodules and 74 adenocarcinomas that were pathologically proven. Types I, II, III and IV vascular relationships were observed in 9, 58, 21 and 20 GGNs, respectively. Type II relationship was the dominating relationship for each GGN group, but significant differences were shown among them. Correlation analysis showed strong correlation between invasive adenocarcinoma and type III and IV relationships. Subgroup analysis indicated that type III was more commonly seen in IAC with comparison to type IV more likely seen in MIA. Different GGNs have different relationships with vessels. Understanding and recognising characteristic GGN-vessel relationships may help identify which GGNs are more likely to be malignant. (orig.)

  17. Contrasting actions of selective inhibitors of angiopoietin-1 and angiopoietin-2 on the normalization of tumor blood vessels.

    Science.gov (United States)

    Falcón, Beverly L; Hashizume, Hiroya; Koumoutsakos, Petros; Chou, Jeyling; Bready, James V; Coxon, Angela; Oliner, Jonathan D; McDonald, Donald M

    2009-11-01

    Angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2) have complex actions in angiogenesis and vascular remodeling due to their effects on Tie2 receptor signaling. Ang2 blocks Ang1-mediated activation of Tie2 in endothelial cells under certain conditions but is a Tie2 receptor agonist in others. We examined the effects of selective inhibitors of Ang1 (mL4-3) or Ang2 (L1-7[N]), alone or in combination, on the vasculature of human Colo205 tumors in mice. The Ang2 inhibitor decreased the overall abundance of tumor blood vessels by reducing tumor growth and keeping vascular density constant. After inhibition of Ang2, tumor vessels had many features of normal blood vessels (normalization), as evidenced by junctional accumulation of vascular endothelial-cadherin, junctional adhesion molecule-A, and platelet/endothelial cell adhesion molecule-1 in endothelial cells, increased pericyte coverage, reduced endothelial sprouting, and remodeling into smaller, more uniform vessels. The Ang1 inhibitor by itself had little noticeable effect on the tumor vasculature. However, when administered with the Ang2 inhibitor, the Ang1 inhibitor prevented tumor vessel normalization, but not the reduction in tumor vascularity produced by the Ang2 inhibitor. These findings are consistent with a model whereby inhibition of Ang2 leads to normalization of tumor blood vessels by permitting the unopposed action of Ang1, but decreases tumor vascularity primarily by blocking Ang2 actions.

  18. The Effect of Silver Nanofibers on the Deformation Properties of Blood Vessels: Towards the Development of New Nanotechnologies to Prevent Rupture of Aneurysms

    Directory of Open Access Journals (Sweden)

    Miguel Gonzalez

    2014-01-01

    Full Text Available An aneurysm is the result of a widening or ballooning of a portion of a blood vessel. The rupture of an aneurysm occurs when the mechanical stress acting on the inner wall exceeds the failure strength of the blood vessel. We propose an innovative approach to prevent the rupture of an aneurysm based on the use of nanotechnology to improve the strength of the blood vessel. We present results on the effect of silver nanofibers on the resistance toward deformation of blood vessels. The silver nanofibers are grown on the surface of the blood vessels. The nanofibers are 120±30 nm in diameter and 2.7±0.8 μm in length. The deformation per applied force of blood vessels was found to decrease from 0.15 m/N in control blood vessels to 0.003 m/N in blood vessels treated with the nanofibers. This represents an increase in the resistance towards deformation of a factor of 50. The increase in the resistance towards deformation is clinically significant since blood pressure increases by factors slightly larger than one in the human body. Treatment of blood vessels with silver nanofibers is a potential translational clinical tool for preventing rupture of aneurysms in a clinical setting.

  19. The Influence for Heart and Blood Vessel of Resperdone%利培酮对心血管的影响

    Institute of Scientific and Technical Information of China (English)

    丁智平; 戴兴海; 廖慧珍

    2002-01-01

    Objective To research the influence of the Risperidone for heart and blood vessel and to contral for Clozapine. Method Schizophrenic patients who were in hospital and conform to diagnostic criteria of CCMD- 2- R were been divided Risperidone group and Clozapine group. Two group patients were been examined EKG before and after treatment one、two、three months. Results The influence for heart and blood vessel of Risperidone group were mainly Sinus bradycardia and T wave change but lower for Clozapine group. The influence was associated with the time of taking the drugs Conclusion There was influence on heart and blood vessel of Risperidone but the extend of influencc was lower for Clozapine and must give rise to pay attention.

  20. Ultrastructural changes in blood vessels in epidermal growth factor treated experimental cutaneous wound model.

    Science.gov (United States)

    Kılıçaslan, Seda M Sarı; Cevher, Sule Coşkun; Peker, Emine G Güleç

    2013-11-01

    This study investigates the impact of epidermal growth factor (EGF) on blood vessels, specifically on the development of intussusceptive angiogenesis in cutaneous wound healing. Excisional wounds were formed on both sides of the medulla spinalis in dorsal location of the rats. The control and EGF-treated groups were divided into two groups with respect to sacrifice day: 5 d and 7 d. EGF was topically applied to the EGF-treated group once a day. The wound tissue was removed from rats, embedded in araldite and paraffin, and then examined under transmission electron and light microscopes. The ultrastructural signs of intussusceptive angiogenesis, such as intraluminal protrusion of endothelial cells and formation of the contact zone of opposite endothelial cells, were observed in the wound. Our statistical analyses, based on light microscopy observations, also confirm that EGF treatment induces intussusceptive angiogenesis. Moreover, we found that induction of EGF impact on intussusceptive angiogenesis is higher on the 7th day of treatment than on the 5th day. This implies that the duration of EGF treatment is important. This research clarifies the effects of EGF on the vessels and proves that EGF induces intussusceptive angiogenesis, being a newer model with respect to sprouting type.

  1. [Injuries to blood vessels near the heart caused by central venous catheters].

    Science.gov (United States)

    Abram, J; Klocker, J; Innerhofer-Pompernigg, N; Mittermayr, M; Freund, M C; Gravenstein, N; Wenzel, V

    2016-11-01

    Injuries to blood vessels near the heart can quickly become life-threatening and include arterial injuries during central venous puncture, which can lead to hemorrhagic shock. We report 6 patients in whom injury to the subclavian artery and vein led to life-threatening complications. Central venous catheters are associated with a multitude of risks, such as venous thrombosis, air embolism, systemic or local infections, paresthesia, hemothorax, pneumothorax, and cervical hematoma, which are not always immediately discernible. The subclavian catheter is at a somewhat lower risk of catheter-associated sepsis and symptomatic venous thrombosis than approaches via the internal jugular and femoral veins. Indeed, access via the subclavian vein carries a substantial risk of pneumo- and hemothorax. Damage to the subclavian vein or artery can also occur during deliberate and inadvertent punctures and result in life-threatening complications. Therefore, careful consideration of the access route is required in relation to the patient and the clinical situation, to keep the incidence of complications as low as possible. For catheterization of the subclavian vein, puncture of the axillary vein in the infraclavicular fossa is a good alternative, because ultrasound imaging of the target vessel is easier than in the subclavian vein and the puncture can be performed much further from the lung.

  2. Streaming flow from ultrasound contrast agents by acoustic waves in a blood vessel model.

    Science.gov (United States)

    Cho, Eunjin; Chung, Sang Kug; Rhee, Kyehan

    2015-09-01

    To elucidate the effects of streaming flow on ultrasound contrast agent (UCA)-assisted drug delivery, streaming velocity fields from sonicated UCA microbubbles were measured using particle image velocimetry (PIV) in a blood vessel model. At the beginning of ultrasound sonication, the UCA bubbles formed clusters and translated in the direction of the ultrasound field. Bubble cluster formation and translation were faster with 2.25MHz sonication, a frequency close to the resonance frequency of the UCA. Translation of bubble clusters induced streaming jet flow that impinged on the vessel wall, forming symmetric vortices. The maximum streaming velocity was about 60mm/s at 2.25MHz and decreased to 15mm/s at 1.0MHz for the same acoustic pressure amplitude. The effect of the ultrasound frequency on wall shear stress was more noticeable. Maximum wall shear stress decreased from 0.84 to 0.1Pa as the ultrasound frequency decreased from 2.25 to 1.0MHz. The maximum spatial gradient of the wall shear stress also decreased from 1.0 to 0.1Pa/mm. This study showed that streaming flow was induced by bubble cluster formation and translation and was stronger upon sonication by an acoustic wave with a frequency near the UCA resonance frequency. Therefore, the secondary radiant force, which is much stronger at the resonance frequency, should play an important role in UCA-assisted drug delivery.

  3. Enhanced Blood Compatibility of Metallocene Polyethylene Subjected to Hydrochloric Acid Treatment for Cardiovascular Implants

    Directory of Open Access Journals (Sweden)

    Saravana Kumar Jaganathan

    2014-01-01

    Full Text Available Blood compatibility of metallocene polyethylene (mPE was investigated after modifying the surface using hydrochloric acid. Contact angle of the mPE exposed to HCl poses a decrease in its value which indicates increasing wettability and better blood compatibility. Surface of mPE analyzed by using FTIR revealed no significant changes in its functional groups after treatment. Furthermore, scanning electron microscope images supported the increasing wettability through the modifications like pit formations and etching on the acid rendered surface. To evaluate the effect of acid treatment on the coagulation cascade, prothrombin time (PT and activated partial thromboplastin time (APTT were measured. Both PT and APTT were delayed significantly (P<0.05 after 60 min exposure implying improved blood compatibility of the surfaces. Hemolysis assay of the treated surface showed a remarkable decrease in the percentage of lysis of red blood cells when compared with untreated surface. Moreover, platelet adhesion assay demonstrated that HCl exposed surfaces deter the attachment of platelets and thereby reduce the chances of activation of blood coagulation cascade. These results confirmed the enhanced blood compatibility of mPE after HCl exposure which can be utilized for cardiovascular implants like artificial vascular prostheses, implants, and various blood contacting devices.

  4. Visualization of tumor-related blood vessels in human breast by photoacoustic imaging system with a hemispherical detector array

    Science.gov (United States)

    Toi, M.; Asao, Y.; Matsumoto, Y.; Sekiguchi, H.; Yoshikawa, A.; Takada, M.; Kataoka, M.; Endo, T.; Kawaguchi-Sakita, N.; Kawashima, M.; Fakhrejahani, E.; Kanao, S.; Yamaga, I.; Nakayama, Y.; Tokiwa, M.; Torii, M.; Yagi, T.; Sakurai, T.; Togashi, K.; Shiina, T.

    2017-01-01

    Noninvasive measurement of the distribution and oxygenation state of hemoglobin (Hb) inside the tissue is strongly required to analyze the tumor-associated vasculatures. We developed a photoacoustic imaging (PAI) system with a hemispherical-shaped detector array (HDA). Here, we show that PAI system with HDA revealed finer vasculature, more detailed blood-vessel branching structures, and more detailed morphological vessel characteristics compared with MRI by the use of breast shape deformation of MRI to PAI and their fused image. Morphologically abnormal peritumoral blood vessel features, including centripetal photoacoustic signals and disruption or narrowing of vessel signals, were observed and intratumoral signals were detected by PAI in breast cancer tissues as a result of the clinical study of 22 malignant cases. Interestingly, it was also possible to analyze anticancer treatment-driven changes in vascular morphological features and function, such as improvement of intratumoral blood perfusion and relevant changes in intravascular hemoglobin saturation of oxygen. This clinical study indicated that PAI appears to be a promising tool for noninvasive analysis of human blood vessels and may contribute to improve cancer diagnosis. PMID:28169313

  5. Comparison of the number of gingival blood vessels between type 2 diabetes mellitus and chronic periodontitis patients: An immunohistological study

    Science.gov (United States)

    Penmetsa, Gautami Subhadra; Baddam, Satyanarayana; Manyam, Ravikanth; Dwarakanath, Chinni Doraswamy

    2015-01-01

    Background: The relationship between diabetes and periodontitis has been studied for more than 50 years and is generally agreed that the periodontal disease is more prevalent in diabetic patients compared to nondiabetics. Vascular changes like increased thickness of basement membrane in small vessels has been reported in diabetic patients, but the quantity of blood vessels in gingiva of diabetic patients has not been discussed much. The aim of this study was to compare the number of blood vessels in gingiva between chronic periodontitis (CP) patients, CP with diabetes (type 2), and normal healthy gingiva. Materials and Methods: The study included 75 patients, divided into three groups of 25 patients each-Group I with healthy periodontium (HP), Group II with CP, and Group III with CP with diabetes mellitus (CPDM). Gingival biopsies were obtained from the subjects undergoing crown lengthening procedure for Group I, and in patients with CP and in CPDM biopsies were collected from teeth undergoing extraction. Sections were prepared for immune histochemical staining with CD34. Results: Difference was observed in the average number of blood vessels when compared between HP, CP, and CPDM groups. Statistical significant difference was observed when the HP and CP groups and HP and CPDM groups were compared. Conclusion: The results of the study indicated that the number of blood vessels in gingival connective tissue is significantly higher in CP and CPDM patients. PMID:26015666

  6. Comparison of the number of gingival blood vessels between type 2 diabetes mellitus and chronic periodontitis patients: An immunohistological study

    Directory of Open Access Journals (Sweden)

    Gautami Subhadra Penmetsa

    2015-01-01

    Full Text Available Background: The relationship between diabetes and periodontitis has been studied for more than 50 years and is generally agreed that the periodontal disease is more prevalent in diabetic patients compared to nondiabetics. Vascular changes like increased thickness of basement membrane in small vessels has been reported in diabetic patients, but the quantity of blood vessels in gingiva of diabetic patients has not been discussed much. The aim of this study was to compare the number of blood vessels in gingiva between chronic periodontitis (CP patients, CP with diabetes (type 2, and normal healthy gingiva. Materials and Methods: The study included 75 patients, divided into three groups of 25 patients each-Group I with healthy periodontium (HP, Group II with CP, and Group III with CP with diabetes mellitus (CPDM.Gingival biopsies were obtained from the subjects undergoing crown lengthening procedure for Group I, and in patients with CP and in CPDM biopsies were collected from teeth undergoing extraction. Sections were prepared for immune histochemical staining with CD34. Results: Difference was observed in the average number of blood vessels when compared between HP, CP, and CPDM groups. Statistical significant difference was observed when the HP and CP groups and HP and CPDM groups were compared. Conclusion: The results of the study indicated that the number of blood vessels in gingival connective tissue is significantly higher in CP and CPDM patients.

  7. Vascular tissue engineering of small-diameter blood vessels: reviewing the electrospinning approach.

    Science.gov (United States)

    Ercolani, Enrico; Del Gaudio, Costantino; Bianco, Alessandra

    2015-08-01

    Vascular tissue engineering is a relevant research field aimed at elaborating and proposing innovative solutions to overcome the drawbacks related to the use of conventional blood vessel substitutes, especially referring to small-diameter grafts. For this aim, electrospinning can be regarded as a valuable technique to produce novel scaffolds with several functional characteristics that can be usefully tailored for the application discussed here. The reproduction of the natural extracellular matrix obtained by processing bioresorbable polymers, either functionalized or not, is driving the biomedical research towards technical solutions that can lead to an actual therapeutic improvement. In this context, this paper reviews those studies focused on the selection of suitable biomaterials for vascular applications, their microstructure, the cell response to polymeric fibres and the strategies considered so far to modify and therefore enhance the performance of final electrospun scaffolds.

  8. Cathodic-controlled and near-infrared organic upconverter for local blood vessels mapping

    Science.gov (United States)

    Yuan, Chih-Hsien; Lee, Chih-Chien; Liu, Chun-Fu; Lin, Yun-Hsuan; Su, Wei-Cheng; Lin, Shao-Yu; Chen, Kuan-Ting; Li, Yan-De; Chang, Wen-Chang; Li, Ya-Ze; Su, Tsung-Hao; Liu, Yu-Hsuan; Liu, Shun-Wei

    2016-08-01

    Organic materials are used in novel optoelectronic devices because of the ease and high compatibility of their fabrication processes. Here, we demonstrate a low-driving-voltage cathodic-controlled organic upconverter with a mapping application that converts near-infrared images to produce images of visible blood vessels. The proposed upconverter has a multilayer structure consisting of a photosensitive charge-generation layer (CGL) and a phosphorescent organic light-emitting diode (OLED) for producing clear images with a high resolution of 600 dots per inch. In this study, temperature-dependent electrical characterization was performed to analyze the interfacial modification of the cathodic-controlled upconverter. The result shows that the upconverter demonstrated a high conversion efficiency of 3.46% because of reduction in the injection barrier height at the interface between the CGL and the OLED.

  9. Weakly swirling flow in a model of blood vessel with stenosis: Numerical and experimental study

    Directory of Open Access Journals (Sweden)

    Yakov A. Gataulin

    2015-12-01

    Full Text Available Investigation of weakly swirling flow in a model of a blood vessel with asymmetrical stenosis has been performed using both experimental flow measurement techniques (ultrasound Doppler and computational fluid dynamics methods. A special attention is paid to getting data for the length of the reverse-flow zone occurring past the stenosis. It has been established that the laminar steady-state flow model is acceptable for numerical analysis of flow past the given-geometry stenosis at Reynolds number values less than 300. At higher values of this parameter, application of the semi-empirical k-ω SST turbulence model is preferable. It has been shown that flow swirl can lead to an increase of the reverse-flow zone.

  10. Ultrastructural analysis of small blood vessels in skin biopsies in CADASIL

    Directory of Open Access Journals (Sweden)

    Lačković Vesna

    2008-01-01

    Full Text Available Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL is an inherited small- and medium-artery disease of the brain caused by mutation of the Notch3 gene. Very often, this disease is misdiagnosed. We examined skin biopsies in two members of the first discovered Serbian family affected by CADASIL. Electron microscopy showed that skin blood vessels of both patients contain numerous deposits of granular osmiophilic material (GOM around vascular smooth muscle cells (VSMCs. We observed degeneration of VSMCs, reorganization of their cytoskeleton and dense bodies, disruption of myoendothelial contacts, and apoptosis. Our results suggest that the presence of GOM in small skin arteries represents a specific marker in diagnosis of CADASIL.

  11. Lattice Boltzmann simulation of behaviour of particles moving in blood vessels under the rolling massage

    Institute of Scientific and Technical Information of China (English)

    Yi Hou-Hui; Yang Xiao-Feng; Wang Cai-Feng; Li Hua-Bing

    2009-01-01

    The rolling massage is one of the most important manipulations in Chinese massage, which is expected to eliminate many diseases. Here, the effect of the rolling massage on a pair of particles moving in blood vessels under rolling massage manipulation is studied by the lattice Boltzmann simulation. The simulated results show that the motion of each particle is considerably modified by the rolling massage, and it depends on the relative rolling velocity, the rolling depth, and the distance between particle position and rolling position. Both particles' translational average velocities increase almost linearly as the rolling velocity increases, and obey the same law. The increment of the average relative angular velocity for the leading particle is smaller than that of the trailing one. The result is helpful for understanding the mechanism of the massage and to further develop the rolling techniques.

  12. Cathodic-controlled and near-infrared organic upconverter for local blood vessels mapping.

    Science.gov (United States)

    Yuan, Chih-Hsien; Lee, Chih-Chien; Liu, Chun-Fu; Lin, Yun-Hsuan; Su, Wei-Cheng; Lin, Shao-Yu; Chen, Kuan-Ting; Li, Yan-De; Chang, Wen-Chang; Li, Ya-Ze; Su, Tsung-Hao; Liu, Yu-Hsuan; Liu, Shun-Wei

    2016-08-31

    Organic materials are used in novel optoelectronic devices because of the ease and high compatibility of their fabrication processes. Here, we demonstrate a low-driving-voltage cathodic-controlled organic upconverter with a mapping application that converts near-infrared images to produce images of visible blood vessels. The proposed upconverter has a multilayer structure consisting of a photosensitive charge-generation layer (CGL) and a phosphorescent organic light-emitting diode (OLED) for producing clear images with a high resolution of 600 dots per inch. In this study, temperature-dependent electrical characterization was performed to analyze the interfacial modification of the cathodic-controlled upconverter. The result shows that the upconverter demonstrated a high conversion efficiency of 3.46% because of reduction in the injection barrier height at the interface between the CGL and the OLED.

  13. [Efferent innervation of pulmonary blood vessels and bronchi in rat (an immunohistochemical study)].

    Science.gov (United States)

    Chumasov, E I; Voronchikhin, P A; Korzhevskiĭ, D É

    2012-01-01

    In this investigation the peculiarities of innervation of bronchi and blood vessels of the lung were studied in 20 rats using immunohistochemical demonstration of synaptophysin and alpha-actin. The results obtained have showen that the densest innervation is typical for bronchial walls, particularly, for the muscular lamina. Synaptophysin-immunoreactive terminals (SFIT) were detected in the bronchi in close association with both circular bundles of smooth muscle cells and microganglia. Dense network of SFIT was found in the pulmonary vein--in its middle tunic formed by cardiomyocytes. In contrast to the bronchi and pulmonary vein, large branches of the pulmonary artery contained no SFIT. We briefly discuss the problem of the origin of the nerve fibers described and their functions and suggest that SFIT are formed by efferent fibers (axons) of neurons arising from either the intrapulmonary parasympathetic ganglia.

  14. Electrospun Polycaprolactone Scaffolds for Small-Diameter Tissue Engineered Blood Vessels

    Science.gov (United States)

    Lee, Carol Hsiu-Yueh

    Cardiovascular disease is the leading cause of death in the United States with many patients requiring coronary artery bypass grafting. The current standard is using autografts such as the saphenous vein or intimal mammary artery, however creating a synthetic graft could eliminate this painful and inconvenient procedure. Large diameter grafts have long been established with materials such as DacronRTM and TeflonRTM, however these materials have not proved successful in small-diameter (biodegradable polymer (polycaprolactone) we utilize our expertise in electrospinning and femtosecond laser ablation to create a novel tri-layered tissue engineered blood vessel containing microchannels. The benefits of creating a tri-layer is to mimic native arteries that contain an endothelium to prevent thrombosis in the inner layer, aligned smooth muscle cells in the middle to control vasodilation and constriction, and a mechanically robust outer layer. The following work evaluates the mechanical properties of such a graft (tensile, fatigue, burst pressure, and suture retention strength), the ability to rapidly align cells in laser ablated microchannels in PCL scaffolds, and the biological integration (co-culture of endothelial and smooth muscle cells) with electrospun PCL scaffolds. The conclusions from this work establish that the electrospun tri-layers provide adequate mechanical strength as a tissue engineered blood vessel, that laser ablated microchannels are able to contain the smooth muscle cells, and that cells are able to adhere to PCL fibers. However, future work includes adjusting microchannel dimensions to properly align smooth muscle cells along with perfect co-cultures of endothelial and smooth muscle cells on the electrospun tri-layer.

  15. First two cases of living related liver transplantation with complicated anatomy of blood vessels in Beijing

    Institute of Scientific and Technical Information of China (English)

    Wen-Han Wu; Yuan-Lian Wan; Long Lee; Yin-Mo Yang; Yan-Ting Huang; Chao-Long Chen; Sheung-Tat Fan

    2004-01-01

    AIM: Living related liver transplantation (LRLT) has been developed in response to the paediatric organ donor shortage.Though it has been succeeded in many centers worldwide,the safety of the donor is still a major concern, especially in donors with anatomy variation. We succeeded in performing the first two cases of living related liver transplantation with complicated anatomy of blood vessels as a way to overcome cadaveric organ shortage in Beijing.METHODS: Two patients, with congenital liver fibrosis and congenital biliary atresia were performed with living donor liver transplantation in our hospital and then followed up from November 12 to December 13, 2001. The two living donors, mother and father, were healthy aged 34 and 35years. One right lobe (segment Ⅴ, Ⅵ, Ⅶ, Ⅷ) and one left lateral lobe (segment Ⅱ and Ⅲ) were used. The grafts weighed 394 g and 300 g. The ratio of graft weight to the standard liver volume (SLV) of donors was 68% and 27%.The graft weight to recipient body weight ratio was 3.2%and 4.4%. The graft weight to recipient estimated standard liver mass (ESLM) ratio was 63% and 85%. The two donors had complicated blood vessel variation.RESULTS: Two patients undergone living donor liver transplantation had good results. Abnormal liver function with high bilirubin level appeared in a few days after operation, but liver function returned to normal one month after operation with bilirubin level almost decreased to near normal. No bleeding, thrombosis, infection and bile leakage occurred. One had an acute rejection and recovered.The two donors recovered in two weeks. One had slight fever because of a little collection in abdomen and recovered after paracentesis and drainage.CONCLUSION: Living donor liver transplantation has been proved to be a good way that offers a unique opportunity of getting a timely liver graft as a response to shortage of pediatric donors, though it could be a technically difficult operation if there is anatomical

  16. SDF-1 controls the muscle and blood vessel formation of the somite.

    Science.gov (United States)

    Abduelmula, Aisha; Huang, Ruijin; Pu, Qin; Tamamura, Hirokazu; Morosan-Puopolo, Gabriela; Brand-Saberi, Beate

    2016-01-01

    Stromal-cell-derived factor-1 (SDF-1), the only ligand of the chemokine receptor CXCR4, is involved in skeletal muscle development. However, its role in the proliferation, differentiation and migration of somite cells is not well understood. Here, we investigated its function during somite development in chicken embryos by using gain-of-function and loss-of-function experiments. Overexpression of SDF-1 was performed by electroporating SDF-1 constructs into the ventrolateral part of the somite, or by injecting SDF-1-expressing cells into the somites of stages HH14-16 chicken embryos. We found that enhanced SDF-1 signaling induced cell proliferation in the somite. This resulted in an increase in number of both myotomal and endothelial cells. In contrast, inhibition of SDF-1/CXCR4 signaling led to a reduction of myotomal cells. Injection of SDF-1 producing cells into the somite induced ectopic localization of myotomal cells in the sclerotome. Although many SDF-1-expressing somite cells colonized the limb, only a few of them developed into muscle cells. This resulted in a reduction of the limb muscle mass. This means that most myogenic progenitors were stopped on their migration towards the limb due to the high concentration of the SDF-1 signal in the somite. Most of the SDF-1-expressing somite cells found in the limb were of endothelial cell fate and they contributed to the increase in limb blood vessels. These results reveal that SDF-1 promotes the proliferation of both myogenic and angiogenic progenitor cells of the somite and controls myotome formation. Furthermore, SDF-1 controls muscle and blood vessel formation in the limb in different ways.

  17. Transgenic quail production by microinjection of lentiviral vector into the early embryo blood vessels.

    Directory of Open Access Journals (Sweden)

    Zifu Zhang

    Full Text Available Several strategies have been used to generate transgenic birds. The most successful method so far has been the injection of lentiviral vectors into the subgerminal cavity of a newly laid egg. We report here a new, easy and effective way to produce transgenic quails through direct injection of a lentiviral vector, containing an enhanced-green fluorescent protein (eGFP transgene, into the blood vessels of quail embryos at Hamburger-Hamilton stage 13-15 (HH13-15. A total of 80 embryos were injected and 48 G0 chimeras (60% were hatched. Most injected embryo organs and tissues of hatched quails were positive for eGFP. In five out of 21 mature G0 male quails, the semen was eGFP-positive, as detected by polymerase chain reaction (PCR, indicating transgenic germ line chimeras. Testcross and genetic analyses revealed that the G0 quail produced transgenic G1 offspring; of 46 G1 hatchlings, 6 were transgenic (6/46, 13.0%. We also compared this new method with the conventional transgenesis using stage X subgerminal cavity injection. Total 240 quail embryos were injected by subgerminal cavity injection, of which 34 (14.1% were hatched, significantly lower than the new method. From these hatched quails semen samples were collected from 19 sexually matured males and tested for the transgene by PCR. The transgene was present in three G0 male quails and only 4/236 G1 offspring (1.7% were transgenic. In conclusion, we developed a novel bird transgenic method by injection of lentiviral vector into embryonic blood vessel at HH 13-15 stage, which result in significant higher transgenic efficiency than the conventional subgerminal cavity injection.

  18. Transgenic quail production by microinjection of lentiviral vector into the early embryo blood vessels.

    Science.gov (United States)

    Zhang, Zifu; Sun, Peng; Yu, Fuxian; Yan, Li; Yuan, Fang; Zhang, Wenxin; Wang, Tao; Wan, Zhiyi; Shao, Qiang; Li, Zandong

    2012-01-01

    Several strategies have been used to generate transgenic birds. The most successful method so far has been the injection of lentiviral vectors into the subgerminal cavity of a newly laid egg. We report here a new, easy and effective way to produce transgenic quails through direct injection of a lentiviral vector, containing an enhanced-green fluorescent protein (eGFP) transgene, into the blood vessels of quail embryos at Hamburger-Hamilton stage 13-15 (HH13-15). A total of 80 embryos were injected and 48 G0 chimeras (60%) were hatched. Most injected embryo organs and tissues of hatched quails were positive for eGFP. In five out of 21 mature G0 male quails, the semen was eGFP-positive, as detected by polymerase chain reaction (PCR), indicating transgenic germ line chimeras. Testcross and genetic analyses revealed that the G0 quail produced transgenic G1 offspring; of 46 G1 hatchlings, 6 were transgenic (6/46, 13.0%). We also compared this new method with the conventional transgenesis using stage X subgerminal cavity injection. Total 240 quail embryos were injected by subgerminal cavity injection, of which 34 (14.1%) were hatched, significantly lower than the new method. From these hatched quails semen samples were collected from 19 sexually matured males and tested for the transgene by PCR. The transgene was present in three G0 male quails and only 4/236 G1 offspring (1.7%) were transgenic. In conclusion, we developed a novel bird transgenic method by injection of lentiviral vector into embryonic blood vessel at HH 13-15 stage, which result in significant higher transgenic efficiency than the conventional subgerminal cavity injection.

  19. Implant-supported auricular prosthesis

    Directory of Open Access Journals (Sweden)

    Aditi Nanda

    2011-01-01

    Full Text Available Differences in the balance of shape, size, and position of body organs are immediately perceived as "looking wrong" and this perception can subject the individual to significant peer ridicule and social ostracism, often expressing as intense shame and anguish in the attitude of the afflicted. Rehabilitation of such patients can be remarkably beneficial on the individual′s self-esteem and body image. The onus of the deed lies in the hands of a team that combines artistic excellence with surgical expertise, by combining the skills of anaplastologists, surgeons, and prosthodontists. This is a review of a few surgical and prosthetic considerations in the management of auricular defect and a case description of management of a patient of microtia following similar guidelines in fabrication of the epithesis.

  20. Implant-supported auricular prosthesis.

    Science.gov (United States)

    Nanda, Aditi; Jain, Veena; Kumar, Rakesh; Kabra, Krishna

    2011-01-01

    Differences in the balance of shape, size, and position of body organs are immediately perceived as "looking wrong" and this perception can subject the individual to significant peer ridicule and social ostracism, often expressing as intense shame and anguish in the attitude of the afflicted. Rehabilitation of such patients can be remarkably beneficial on the individual's self-esteem and body image. The onus of the deed lies in the hands of a team that combines artistic excellence with surgical expertise, by combining the skills of anaplastologists, surgeons, and prosthodontists. This is a review of a few surgical and prosthetic considerations in the management of auricular defect and a case description of management of a patient of microtia following similar guidelines in fabrication of the epithesis.

  1. Implant-supported auricular prosthesis

    OpenAIRE

    Aditi Nanda; Veena Jain; Rakesh Kumar; Krishna Kabra

    2011-01-01

    Differences in the balance of shape, size, and position of body organs are immediately perceived as "looking wrong" and this perception can subject the individual to significant peer ridicule and social ostracism, often expressing as intense shame and anguish in the attitude of the afflicted. Rehabilitation of such patients can be remarkably beneficial on the individual′s self-esteem and body image. The onus of the deed lies in the hands of a team that combines artistic excellence with surgic...

  2. Use of the Structure of Blood Vessel for Detection of Brain Aneurysm and Route Search to Brain Aneurysm

    Directory of Open Access Journals (Sweden)

    Toshihide Miyagi

    2013-08-01

    Full Text Available In this research, we constructed functions that are necessary for the operation simulation system which assists medical students to inhibit brain aneurysm from exploding. The system reported in this paper is "detection of blood vessels", "detection of brain aneurysm" and "route planning to brain aneurysm". Not only the detection method but also the method to reduce the miss detection is realized for the detection of blood vessel. Finally, the future work will be shown including construction of head model consisting of artery, vein, brain and cranium.

  3. Predicting effects of blood flow rate and size of vessels in a vasculature on hyperthermia treatments using computer simulation

    Directory of Open Access Journals (Sweden)

    Shih Tzu-Ching

    2010-03-01

    Full Text Available Abstract Background Pennes Bio Heat Transfer Equation (PBHTE has been widely used to approximate the overall temperature distribution in tissue using a perfusion parameter term in the equation during hyperthermia treatment. In the similar modeling, effective thermal conductivity (Keff model uses thermal conductivity as a parameter to predict temperatures. However the equations do not describe the thermal contribution of blood vessels. A countercurrent vascular network model which represents a more fundamental approach to modeling temperatures in tissue than do the generally used approximate equations such as the Pennes BHTE or effective thermal conductivity equations was presented in 1996. This type of model is capable of calculating the blood temperature in vessels and describing a vasculature in the tissue regions. Methods In this paper, a countercurrent blood vessel network (CBVN model for calculating tissue temperatures has been developed for studying hyperthermia cancer treatment. We use a systematic approach to reveal the impact of a vasculature of blood vessels against a single vessel which most studies have presented. A vasculature illustrates branching vessels at the periphery of the tumor volume. The general trends present in this vascular model are similar to those shown for physiological systems in Green and Whitmore. The 3-D temperature distributions are obtained by solving the conduction equation in the tissue and the convective energy equation with specified Nusselt number in the vessels. Results This paper investigates effects of size of blood vessels in the CBVN model on total absorbed power in the treated region and blood flow rates (or perfusion rate in the CBVN on temperature distributions during hyperthermia cancer treatment. Also, the same optimized power distribution during hyperthermia treatment is used to illustrate the differences between PBHTE and CBVN models. Keff (effective thermal conductivity model delivers the

  4. Lymphatic and blood vessels in basal and triple-negative breast cancers: characteristics and prognostic significance.

    Science.gov (United States)

    Mohammed, Rabab A A; Ellis, Ian O; Mahmmod, Ali M; Hawkes, E Claire; Green, Andrew R; Rakha, Emad A; Martin, Stewart G

    2011-06-01

    Basal and triple-negative breast cancer phenotypes are characterised by unfavourable biological behaviour and outcome. Although certain studies have examined their pathological and molecular profile, the vascular characteristics of lymphatic and blood vessels have not been examined. Immunohistochemical staining with podoplanin, CD34 and CD31 was used to examine lymphatic and microvessel density, as well as vascular invasion in 197 basal-like and in 99 triple-negative breast tumours and compared against 200 non-basal and 334 non-triple-negative cases. All specimens were lymph node negative. Vascular invasion was identified as blood or lymphatic vascular invasion by the differential expression of markers. All measurements were correlated with clinicopathological features and prognosis. No significant difference was detected between the basal and triple-negative groups in terms of lymphatic or microvessel density or vascular invasion. However, both the basal and the triple-negative groups showed significantly higher microvessel density than did the non-basal and non-triple-negative groups (P=0.017 and Pcontrols. Interestingly, vascular invasion, almost entirely lymphatic invasion, was detected in 27% of the basal and in 26% of the triple-negative groups with no significant difference in comparison with control groups. In both basal and triple negatives, vascular invasion was associated with poorer survival by univariate and multivariate analyses. The 20-year overall survival rate in basal-like tumours was 55% in vascular invasion-positive cases compared with 73% in vascular invasion-negative tumours (P=0.012), and 46% in triple-negative vascular invasion-positive compared with 79% in vascular invasion-negative tumours (P=0.001). Basal-like vs non-basal-like and triple-negative vs non-triple-negative tumours have similar vascular characteristics in terms of lymphatic vessel density and vascular invasion but higher microvessel density, suggesting that such groups may

  5. [In vitro study of regulation of shear stress on antithrombogenic potentials of endothelialized polyurethane small diameter artificial blood vessel].

    Science.gov (United States)

    Yang, Zhen; Tao, Jun; Wang, Jiemei; Tu, Chang; Feng, Lianqiang; Pan, Shirong; Ma, Hong

    2008-06-01

    This study was designed to investigate the changes of prostaglandin I2 (PGI2) and nitric oxide (NO) secreted by endothelialized polyurethane small diameter artificial blood vessel. The peripheral blood mononuclear cells of healthy adult were separated and induced into endothelial progenitor cells (EPCs), which were identified by the methods of discrepancy microphage and fluorescent immunology labeling. After the induced cells being seeded on the polyurethane small-diameter artificial vessels, the endothelialized polyurethane small diameter artificial blood vessels were divided into four different experimental groups, including stationary group, low-flow shear stress group (5 dynes/cm2), medium-flow shearstress group (15 dynes/cm2), and high-flow shear stress group (25 dynes/cm2). Then, the levels of 6-ketoprostaglandin F1alpha (6-keto-PGF1alpha) and NO of different time were measured by enzyme-linked immunosorbent assay and nitrate reductase methods. The peripheral blood mononuclear cells differentiated into EPCs. They presented typical "spindie-shaped" appearance, and they were positively labeled by fluorescent acetylated-LDL, lectin, FLK-1 and vWF. Shear stress enhanced the production of NO and 6-keto-PGF1alpha by EPCs in a dose-dependent manner. Therefore, shear stress increases the secretion of NO and PGI2 by EPC, which suggests that shear stress can improve the antithrombogenic potentials of endothelialized polyurethane small diameter artificial blood vessel.

  6. Application of LMA-flexible and total intravenous anesthesia in tympanoplusty with prosthesis implant%可弯曲喉罩联合静脉麻醉在听力重建术中的应用

    Institute of Scientific and Technical Information of China (English)

    宋晓红; 李天佐; 杨静; 李小葵

    2011-01-01

    目的 观察可弯曲喉罩联合静脉麻醉用于人工听骨听力重建术的效果.方法 择期人工听骨听力重建术患者40例,随机均分为可弯曲喉罩组(F组)和气管内插管组(I组),均采用瑞芬太尼一丙泊酚静脉麻醉.记录两组SBP、DBP和HR,术野清晰度评分及自主呼吸恢复时间、拔管时间及BIS.结果 术中F组SBP、DBP低于I组,术野清晰度优于I组;拔管时,F组SBP、DBP及HR波动小于I组(P<0.05)、呛咳反应更轻(P<0.01);F组呼吸恢复及拔管时间长于I组(P<0.05);F组BIS值高于I组(P<0.05).结论 与气管内插管相比,可弯曲喉罩联合静脉麻醉应用于人工听骨听力重建术更具优势,但需注意麻醉深度监测.%Objective To observe the characteristics and resuscitation quality of total intravenous anesthesia in combination with LMA flexible in tympanoplasty with prosthesis implant.Methods Forty patients undertaking tympanoplasty with prosthesis implant were randomly divided into two groups: group F (n=20, with LMA flexible) and group Ⅰ (n=20, with endotreacheal intubation).In both groups anesthesia were maintained with remifentanil and propofol.Hemodynamic index, surgical field score, cough reflex during extubation period and recovery time were recorded.Results In the operation period, the SBP and DBP was lower in group F than that in group Ⅰ, and the surgical field score was higher in group Ⅰ.While in the extubation period, cough reflex was significantly suppressed in group F (P<0.01) and the increase of SBP, DBP and HR was prominent in group Ⅰ (P<0.05), but the time of extubation was delayed in group F(P<0.05).At the moment of extubation, the BIS value in group F was higher than that of group Ⅰ (P<0.05).Conclusion The resuscitation quality and the safety of extuhation in tympanoplasty with prosthesis implant were enhanced by use of LMA-flexible.

  7. Outcome of implanting penile prosthesis for tr eating erectile dysfunction: experience with 42 cases%阴茎假体植入术治疗勃起功能障碍:42例报告

    Institute of Scientific and Technical Information of China (English)

    X. J.Xuan; D.H. Wang; P. Sun; H. Mei

    2007-01-01

    Aim: To report a short-time result of three-piece inflatable penile prosthesis (IPP) implantation on treating patients with organic erectile dysfunction (ED). Methods: Three-piece IPPs were implanted in 42 Chinese patients with ED refractory to systemic treatment between May 2002 and May 2004. The etiologies of ED were neurogenic (28 with paraplegia and seven with traumatic nervi-erigentes injury); congenital venous leakage (5 cases), fibrosis of corpus cavernosum (lcase) and Klinefelter's syndrome (1 case). The follow-up period ranged from 24 to 57 months.Results: Implantation procedures were successfully performed upon all 42 patients. The length of implanted prosthesis was from 13 cm to 18 cm, and the diameter was 1 cm. The implanted prosthesis was made by the Medical Instrumentation Company of Muping (Muping, Shandong, China). Localized infection occurred in only one patient and mechanical complications occurred in five patients. Coitus could be performed in 41 cases (97.6%). Three patients with congenital venous leakage made their spouses pregnant after implantation. Conclusion: Implantation of patients because of its efficacy. (Asian J Androl 2007 Sep; 9: 716-719)%目的:探讨中国产(中华人民共和国医疗器械注册证国药管械准字2002第3460989号)三件套可膨胀性阴茎假体植入术治疗器质性勃起功能障碍疗效.方法:2002年5月至2004年5月,42例非手术治疗无效的勃起功能障碍的中国病人进行了三件套可膨胀阴茎假体植入术治疗.勃起功能障碍的病因包括相关神经损伤(28例瘫痪患者和7例外伤性神经损伤患者)、先天性静脉漏(5例)、海绵体纤维化(1例)、以及Klinefelter综合征(1例).随访时间为24-57个月.结果:42例病人的假体植入术均获成功.植入假体的长度在13-18厘米之间,直径为1厘米.术后1例病人发生了局部感染,有5例病人出现了机械故障.41例病人(97.6%)可以进行满意的性生活.假体植入后有3例

  8. Aging in blood vessels. Medicinal agents FOR systemic arterial hypertension in the elderly.

    Science.gov (United States)

    Rubio-Ruiz, María Esther; Pérez-Torres, Israel; Soto, María Elena; Pastelín, Gustavo; Guarner-Lans, Verónica

    2014-11-01

    Aging impairs blood vessel function and leads to cardiovascular disease. The mechanisms underlying the age-related endothelial, smooth muscle and extracellular matrix vascular dysfunction are discussed. Vascular dysfunction is caused by: (1) Oxidative stress enhancement. (2) Reduction of nitric oxide (NO) bioavailability, by diminished NO synthesis and/or augmented NO scavenging. (3) Production of vasoconstrictor/vasodilator factor imbalances. (4) Low-grade pro-inflammatory environment. (5) Impaired angiogenesis. (6) Endothelial cell senescence. The aging process in vascular smooth muscle is characterized by: (1) Altered replicating potential. (2) Change in cellular phenotype. (3) Changes in responsiveness to contracting and relaxing mediators. (4) Changes in intracellular signaling functions. Systemic arterial hypertension is an age-dependent disorder, and almost half of the elderly human population is hypertensive. The influence of hypertension on the aging cardiovascular system has been studied in models of hypertensive rats. Treatment for hypertension is recommended in the elderly. Lifestyle modifications, natural compounds and hormone therapies are useful for initial stages and as supporting treatment with medication but evidence from clinical trials in this population is needed. Since all antihypertensive agents can lower blood pressure in the elderly, therapy should be based on its potential side effects and drug interactions.

  9. Characterization of Imidazoline Receptors in Blood Vessels for the Development of Antihypertensive Agents

    Directory of Open Access Journals (Sweden)

    Mei-Fen Chen

    2014-01-01

    Full Text Available It has been indicated that activation of peripheral imidazoline I2-receptor (I-2R may reduce the blood pressure in spontaneously hypertensive rats (SHRs. Also, guanidinium derivatives show the ability to activate imidazoline receptors. Thus, it is of special interest to characterize the I-2R using guanidinium derivatives in blood vessels for development of antihypertensive agent(s. Six guanidinium derivatives including agmatine, amiloride, aminoguanidine, allantoin, canavanine, and metformin were applied in this study. Western blot analysis was used for detecting the expression of imidazoline receptor in tissues of Wistar rats. The isometric tension of aortic rings isolated from male rats was also estimated. The expression of imidazoline receptor on rat aorta was identified. However, guanidinium derivatives for detection of aortic relaxation were not observed except agmatine and amiloride which induced a marked relaxation in isolated aortic rings precontracted with phenylephrine or KCl. Both relaxations induced by agmatine and amiloride were attenuated by glibenclamide at concentration enough to block ATP-sensitive potassium (KATP channels. Meanwhile, only agmatine-induced relaxation was abolished by BU224, a selective antagonist of imidazoline I2-receptors. Taken together, we suggest that agmatine can induce vascular relaxation through activation of peripheral imidazoline I2-receptor to open KATP channels. Thus, agmatine-like compound has the potential to develop as a new therapeutic agent for hypertension in the future.

  10. Characterization of imidazoline receptors in blood vessels for the development of antihypertensive agents.

    Science.gov (United States)

    Chen, Mei-Fen; Tsai, Jo-Ting; Chen, Li-Jen; Wu, Tung-Pi; Yang, Jia-Jang; Yin, Li-Te; Yang, Yu-Lin; Chiang, Tai-An; Lu, Han-Lin; Wu, Ming-Chang

    2014-01-01

    It has been indicated that activation of peripheral imidazoline I2-receptor (I-2R) may reduce the blood pressure in spontaneously hypertensive rats (SHRs). Also, guanidinium derivatives show the ability to activate imidazoline receptors. Thus, it is of special interest to characterize the I-2R using guanidinium derivatives in blood vessels for development of antihypertensive agent(s). Six guanidinium derivatives including agmatine, amiloride, aminoguanidine, allantoin, canavanine, and metformin were applied in this study. Western blot analysis was used for detecting the expression of imidazoline receptor in tissues of Wistar rats. The isometric tension of aortic rings isolated from male rats was also estimated. The expression of imidazoline receptor on rat aorta was identified. However, guanidinium derivatives for detection of aortic relaxation were not observed except agmatine and amiloride which induced a marked relaxation in isolated aortic rings precontracted with phenylephrine or KCl. Both relaxations induced by agmatine and amiloride were attenuated by glibenclamide at concentration enough to block ATP-sensitive potassium (KATP) channels. Meanwhile, only agmatine-induced relaxation was abolished by BU224, a selective antagonist of imidazoline I2-receptors. Taken together, we suggest that agmatine can induce vascular relaxation through activation of peripheral imidazoline I2-receptor to open KATP channels. Thus, agmatine-like compound has the potential to develop as a new therapeutic agent for hypertension in the future.

  11. Ultrasound sonication with microbubbles disrupts blood vessels and enhances tumor treatments of anticancer nanodrug

    Directory of Open Access Journals (Sweden)

    Lin CY

    2012-04-01

    Full Text Available Chung-Yin Lin1*, Hsiao-Ching Tseng1*, Heng-Ruei Shiu1, Ming-Fang Wu2, Cheng-Ying Chou3, Win-Li Lin1,41Institute of Biomedical Engineering, 2Laboratory Animal Center, 3Department of Bio-Industrial Mechatronics Engineering, National Taiwan University, Taipei, Taiwan; 4Division of Medical Engineering Research, National Health Research Institutes, Miaoli, Taiwan*These authors contributed equally to this workAbstract: Ultrasound (US sonication with microbubbles (MBs has the potential to disrupt blood vessels and enhance the delivery of drugs into the sonicated tissues. In this study, mouse ear tumors were employed to investigate the therapeutic effects of US, MBs, and pegylated liposomal doxorubicin (PLD on tumors. Tumors started to receive treatments when they grew up to about 15 mm3 (early stage with injection of PLD 10 mg/kg, or up to 50 mm3 (medium stage with PLD 6 (or 4 mg/kg. Experiments included the control, PLD alone, PLD + MBs + US, US alone, and MBs + US groups. The procedure for the PLD + MBs + US group was that PLD was injected first, MB (SonoVue injection followed, and then US was immediately sonicated on the tumor. The results showed that: (1 US sonication with MBs was always able to produce a further hindrance to tumor growth for both early and medium-stage tumors; (2 for the medium-stage tumors, 6 mg/kg PLD alone was able to inhibit their growth, while it did not work for 4 mg/kg PLD alone; (3 with the application of MBs + US, 4 mg/kg PLD was able to inhibit the growth of medium-stage tumors; (4 for early stage tumors after the first treatment with a high dose of PLD alone (10 mg/kg, the tumor size still increased for several days and then decreased (a biphasic pattern; (5 MBs + US alone was able to hinder the growth of early stage tumors, but unable to hinder that of medium stage tumors. The results of histological examinations and blood perfusion measurements indicated that the application of MBs + US disrupts the tumor blood

  12. 21 CFR 888.3100 - Ankle joint metal/composite semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3100 Section 888.3100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Ankle joint metal/composite semi-constrained cemented prosthesis. (a) Identification. An ankle joint metal/composite semi-constrained cemented prosthesis is a device intended to be implanted to replace...

  13. 21 CFR 888.3400 - Hip joint femoral (hemi-hip) metallic resurfacing prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3400 Section 888.3400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... femoral (hemi-hip) metallic resurfacing prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metallic resurfacing prosthesis is a device intended to be implanted to replace a portion of the hip...

  14. 21 CFR 888.3170 - Elbow joint radial (hemi-elbow) polymer prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Elbow joint radial (hemi-elbow) polymer prosthesis... (hemi-elbow) polymer prosthesis. (a) Identification. An elbow joint radial (hemi-elbow) polymer prosthesis is a device intended to be implanted made of medical grade silicone elastomer used to replace...

  15. 21 CFR 888.3220 - Finger joint metal/polymer constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3220 Section 888.3220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/polymer constrained cemented prosthesis. (a) Identification. A finger joint metal/polymer constrained cemented prosthesis is a device intended to be implanted to replace a metacarpophalangeal...

  16. 21 CFR 888.3210 - Finger joint metal/metal constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3210 Section 888.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/metal constrained cemented prosthesis. (a) Identification. A finger joint metal/metal constrained cemented prosthesis is a device intended to be implanted to replace a metacarpophalangeal (finger)...

  17. 21 CFR 888.3370 - Hip joint (hemi-hip) acetabular metal cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3370 Section 888.3370 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... (hemi-hip) acetabular metal cemented prosthesis. (a) Identification. A hip joint (hemi-hip) acetabular metal cemented prosthesis is a device intended to be implanted to replace a portion of the hip...

  18. 21 CFR 888.3350 - Hip joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3350 Section 888.3350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/polymer semi-constrained cemented prosthesis. (a) Identification. A hip joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a hip joint. The device...

  19. 21 CFR 888.3800 - Wrist joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3800 Section 888.3800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Wrist joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. A wrist joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a wrist...

  20. 21 CFR 888.3300 - Hip joint metal constrained cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3300 Section 888.3300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal constrained cemented or uncemented prosthesis. (a) Identification. A hip joint metal constrained cemented or uncemented prosthesis is a device intended to be implanted to replace a hip joint. The...

  1. 21 CFR 888.3340 - Hip joint metal/composite semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3340 Section 888.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Hip joint metal/composite semi-constrained cemented prosthesis. (a) Identification. A hip joint metal/composite semi-constrained cemented prosthesis is a two-part device intended to be implanted to replace...

  2. 21 CFR 888.3110 - Ankle joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3110 Section 888.3110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Ankle joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An ankle joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an...

  3. 21 CFR 888.3160 - Elbow joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3160 Section 888.3160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Elbow joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An elbow joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an...

  4. 21 CFR 888.3180 - Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented prosthesis. 888.3180 Section 888.3180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis. (a) Identification. An elbow joint humeral (hemi-elbow) metallic uncemented prosthesis is a device intended to be implanted made of...

  5. 21 CFR 888.3120 - Ankle joint metal/polymer non-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3120 Section 888.3120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/polymer non-constrained cemented prosthesis. (a) Identification. An ankle joint metal/polymer non-constrained cemented prosthesis is a device intended to be implanted to replace an ankle joint. The...

  6. 21 CFR 888.3660 - Shoulder joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3660 Section 888.3660 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Shoulder joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. A shoulder joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace...

  7. 21 CFR 888.3200 - Finger joint metal/metal constrained uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3200 Section 888.3200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/metal constrained uncemented prosthesis. (a) Identification. A finger joint metal/metal constrained uncemented prosthesis is a device intended to be implanted to replace a metacarpophalangeal...

  8. 21 CFR 888.3310 - Hip joint metal/polymer constrained cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented prosthesis. 888.3310 Section 888.3310 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Hip joint metal/polymer constrained cemented or uncemented prosthesis. (a) Identification. A hip joint metal/polymer constrained cemented or uncemented prosthesis is a device intended to be implanted...

  9. Linking of total elbow prosthesis during surgery; a biomechanical analysis

    NARCIS (Netherlands)

    Vos, M.J. de; Wagener, M.L.; Hendriks, J.C.M.; Eygendaal, D.; Verdonschot, N.J.J.

    2013-01-01

    BACKGROUND: Presently, 2 types of elbow prostheses are used: unlinked and linked. The Latitude total elbow prosthesis allows the surgeon to decide during the implantation whether the prosthesis is placed unlinked or linked, and whether the native radial head is retained, resected, or replaced. The p

  10. [Coronary artery blood flow velocity non-invasively measured using a vessel-tracking pulsed Doppler system].

    Science.gov (United States)

    Tateishi, O; Aizawa, O; Okamura, T; Yoshida, T; Furuhata, H; Seo, Y; Iinuma, K; Shiki, E

    1988-09-01

    A newly-developed noninvasive method was used to measure left coronary blood flow during phantom experiments. Two techniques were used in which: (1) the sample position can always be set in a fluctuating vessel using a wall echo-tracking method with a phase-locked-loop, and (2) the Doppler reference signal was generated separately synchronous with the wall echo signal. These techniques were combined, using a commercially available pulsed Doppler apparatus (SSH-40B: Toshiba). Basic experiments were performed using a blood vessel phantom to verify the validity of these systems. Blood flow velocity in the fluctuating tube could be measured clearly using a vessel-tracking method. The blood flow velocity of the left anterior descending artery was measured in three normal subjects and in seven patients from the third intercostal space along the left sternal border. The velocity pattern was characterized by a crescendo-decrescendo shape in diastole. The peak velocity which appeared in diastole ranged from 19 to 69 cm/sec, with no difference by disease entity. However, in all cases, the blood flow velocity signals were marred by extraneous signals, making it impossible to measure blood flow velocity during systole. Further improvement of the system is mandatory in order to use this flowmeter clinically.

  11. Hypoxia-inducible factor and vascular endothelial growth factor in the neuroretina and retinal blood vessels after retinal ischemia

    DEFF Research Database (Denmark)

    Håkansson, Gisela; Gesslein, Bodil; Gustafsson, Lotta

    2010-01-01

    Retinal ischemia arises from circulatory failure. As the retinal blood vessels are key organs in circulatory failure, our aim was to study the retinal vasculature separately from the neuroretina to elucidate the role of hypoxia-inducible factor (HIF) 1α and 1β and vascular endothelial growth factor...

  12. MRA Images Identification of the Artery Blood Vessel of the Knee with SOM LVQ Neural Networks as Auxiliary.

    Science.gov (United States)

    Huang, Hung-Chun; Chien, Chia-Hung; Shih, Ting-Fang; Chong, Fok-Ching

    2005-01-01

    The ways of angiography are divided into two kinds at present: the invasive type and the non invasive type. Because the magnetic resonance angiography (MRA) has advantages of the non invasive type, thus people can accept MRA more easily. Presently, to diagnoses for the initial stage triage of the blood vessel on clinic by MRA mostly. We to be allowed to see clearly that the shape of lower limb artery which like the dendrite and the blood vessel is thick from the trunk to the thin branch, also we can see the narrow embolism and the blocked place through MRA. This study is aiming at the image of artery of blood vessel by MRA assay, and is attempting to use two-dimensional structure of SOM and LVQ to make out topologies for the shape of artery of blood vessel. We expect that MRA could be useful tools for earlier on the quick triage and auxiliary diagnosis of doctors. By actual examples truly prove that patients after peripheral arterial occlusive disease (PAOD) treatment can diagnose effectively, shorten the time of patients waiting for reports and improve the whole efficiency of the medical treatment system.

  13. NOK/STYK1 promotes the genesis and remodeling of blood and lymphatic vessels during tumor progression.

    Science.gov (United States)

    Liu, Yue; Li, Tianqi; Hu, Dan; Zhang, Shuping

    2016-09-01

    Previous studies have indicated that the overexpression of NOK, also named STYK1, led to tumorigenesis and metastasis. Here, we provide evidence that increased expression of NOK/STYK1 caused marked alterations in the overall and inner structures of tumors and substantially facilitates the genesis and remodeling of the blood and lymphatic vessels during tumor progression. In particular, NOK-expressed HeLa stable cells (HeLa-K) significantly enhanced tumor growth and metastasis in xenografted nude mice. Hematoxylin and eosin (HE) staining demonstrated that the tumor tissues generated by HeLa-K cells were much more ichorous and had more interspaces than those generated by control HeLa cells (HeLa-C). The fluorescent areas stained with cluster of differentiation 31 (CD31), a marker protein for blood vessels, appeared to be in different patterns. The total blood vessels, especially the ring patterns, within the tumors of the HeLa-K group were highly enriched compared with those in the HeLa-C group. NOK-HA was demonstrated to be well colocalized with CD31 in the wall of the tubular structures within tumor tissues. Interestingly, antibody staining of the lymphatic vessel endothelial hyaluronan receptor (LYVE-1) further revealed the increase in ring (oratretic strip-like) lymphatic vessels in either the peritumoral or intratumoral areas in the HeLa-K group compared with the HeLa-C group. Consistently, the analysis of human cancerous tissue also showed that NOK was highly expressed in the walls of tubular structures. Thus, our results reveal a novel tumorigenic function of NOK to mediate the genesis and remodeling of blood and lymphatic vessels during tumor progression.

  14. Association of body composition and blood pressure categories with retinal vessel diameters in primary school children.

    Science.gov (United States)

    Imhof, Katharina; Zahner, Lukas; Schmidt-Trucksäss, Arno; Hanssen, Henner

    2016-06-01

    Alterations in retinal vessel diameters have been shown to be predictive of cardiovascular risk in adults and children. The aim of our study was to examine the association of body composition and blood pressure (BP) categories with retinal vessel diameters in school children. We examined anthropometric parameters, BP and retinal arteriolar (CRAE) and venular (CRVE) diameters as well as the arteriolar-to-venular diameter ratio (AVR) in 391 children (age: 7.3, s.d. 0.4). Differences between the lowest and highest BP quartiles indicated that higher systolic and diastolic BP were associated with narrower CRAE (P<0.001 for both). Children in the highest weight quartile had narrower CRAE compared with the lowest quartile (P=0.05). In the regression analysis, systolic and diastolic BP were associated with arteriolar narrowing (-0.4 measuring units (mu) per mm Hg, 95% confidence interval: [-0.6; -0.3] and -0.6 mu per mm Hg [-0.7; -0.4], respectively; P<0.001 for both). An independent association was found for diastolic BP only. Compared with normotensives (NT; 74.4% of cohort), arteriolar narrowing was already seen in children categorized as pre-hypertensive (PHT) (11.5% of cohort), which was similar to HT children (14.1% of cohort) (NT: mean 207.2 [205.6; 208.7] mu; PHT: 201.7 [197.8; 205.7] mu; HT: 199.7 [196.2; 203.3] mu; P=0.01 for PHT vs. NT and P<0.001 for HT vs. NT in systolic BP). Our results suggest that systolic and diastolic BP are main determinants of retinal arteriolar diameters; and therefore, microvascular health in young children. Pre-hypertension seems to be associated with retinal microvascular alterations early in life.

  15. Abiotrophia defectiva knee prosthesis infection: A case report

    Directory of Open Access Journals (Sweden)

    Levy Pierre-Yves

    2011-09-01

    Full Text Available Abstract Background Abiotrophia species have rarely been implicated in osteoarticular infections. We report one case of an A. defectiva knee prosthesis infection. Case presentation A 71-year-old man of Italian origin presented with pain and swelling of the knee four years after the implantation of a total knee replacement prosthesis. While standard culturing of the synovial fluid resulted in no isolation of microorganisms, the direct inoculation of the synovial fluid into a rich culture medium resulted in the identification of A. defectiva by polymerase chain reaction sequencing. Repeated attempts of culturing microorganisms from blood were negative, and echocardiograms and colonoscopies were unremarkable. High-dose amoxicillin for nine months and a two-stage replacement of the knee prosthesis led to full patient recovery by the time of the 12-month follow-up examination. Conclusions Because Abiotrophia spp. are fastidious microorganisms, it is likely that cases of Abiotrophia orthopedic infection are misdiagnosed as culture-negative infections. Direct inoculation of synovial fluids into rich broth medium and further polymerase chain reaction-based detection of culture-negative synovial fluids are key tests for accurate documentation and detection of these infections.

  16. A new resorbable device for ligation of blood vessels - A pilot study

    Directory of Open Access Journals (Sweden)

    Borg Niklas

    2011-07-01

    Full Text Available Abstract Background During surgery, controlled haemostasis to prevent blood loss is vital for a successful outcome. It can be difficult to ligate vessels located deep in the abdomen. A device that is easy to use and enables secure ligatures could be beneficial. Cable ties made of nylon have been used for ligation but the non-resorbable material caused tissue reactions. The objective of this study was to use a resorbable material to construct a device with a self-locking mechanism and to test its mechanical strength and ligation efficiency. Methods The device was manufactured by injection moulding of polydioxanone, a resorbable polymer used for suture materials. Polydioxanone with inherent viscosities of 1.9 dL/g and 1.3 dL/g were tested. The device consisted of a perforated flexible band which could be pulled through a case with a locking mechanism. After a first version of the device had been tested, some improvements were made. The locking case was downsized, corners were rounded off, the band was made thicker and the mould was redesigned to produce longer devices. Tensile tests were performed with the second version. The first version of the device was used to ligate the ovarian pedicle in a euthanized dog and to test echogenicity of the device with ultrasound. Compression of vessels of the ovarian pedicle was examined by histology. Both versions of the device were tested for haemostasis of and tissue grip on renal arteries in six anaesthetised pigs. Results The tensile strength of the flexible band of the devices with inherent viscosity of 1.9 dL/g was 50.1 ± 5.5 N (range 35.2-62.9 N, n = 11 and the devices with inherent viscosity of 1.3 dL/g had a tensile strength of 39.8 ± 8.1 N (range 18.6-54.2 N, n = 11. Injection moulding of the polymer with lower inherent viscosity resulted in a longer flow distance. Both versions of the device had an effective tissue grip and complete haemostasis of renal arteries was verified. The device attached

  17. 78 FR 38994 - Implanted Blood Access Devices for Hemodialysis; Draft Guidance for Industry and Food and Drug...

    Science.gov (United States)

    2013-06-28

    ... HUMAN SERVICES Food and Drug Administration Implanted Blood Access Devices for Hemodialysis; Draft Guidance for Industry and Food and Drug Administration Staff; Availability AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is announcing...

  18. Cyclic volatile methylsiloxanes in human blood as markers for ruptured silicone gel-filled breast implants.

    Science.gov (United States)

    Rosendahl, Pia; Hippler, Joerg; Schmitz, Oliver J; Hoffmann, Oliver; Rusch, Peter

    2016-05-01

    The replacement of medical-grade silicone with industrial-grade silicone material in some silicone gel-filled breast implants (SBI) manufactured by Poly Implant Prothèse and Rofil Medical Nederland B.V., reported in 2010, which resulted in a higher rupture tendency of these SBI, demonstrates the need for non-invasive, sensitive monitoring and screening methods. Therefore a sensitive method based on large volume injection-gas chromatography coupled to mass spectrometry (LVI-GC/MS) was developed to determine octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclo-hexasiloxane (D6) in blood samples from women with intact (n = 13) and ruptured SBI (n = 11). With dichloromethane extraction, sample cooling during preparation, and analysis extraction efficiencies up to 100 % and limits of detection of 0.03-0.05 ng D4-D6/g blood were achieved. Blood samples from women with SBI were investigated. In contrast to women with intact SBI, in blood from women with ruptured SBI higher D4 and D6 concentrations up to 0.57 ng D4/g blood and 0.16 ng D6/g blood were detected. With concentrations above 0.18 D4 ng/blood and 0.10 ng D6/g blood as significant criteria for ruptured SBI, this developed analytical preoperative diagnostic method shows a significant increase of the recognition rate. Finally a higher precision (error rate 17%) than the commonly used clinical diagnostic method, mamma sonography (error rate 46%), was achieved.

  19. [An obturator prosthesis in a patient with perfect dentition. Functional, esthetic approach].

    Science.gov (United States)

    Razouk, O; Sidibe, C A; Dichamp, J; Bertrand, J C

    1994-01-01

    A prosthesis was implanted immediately after operation for a velo-palatal tissue defect in an active young female patient in order to avoid function, psychological and social complications involved with this mutilation. The three classical steps of the process were performed: immediate implantation of the prosthesis, temporary prosthesis, definitive prosthesis. Anchoring to the teeth maintained the prosthesis in position. A functional print is always needed to obtain perfect closure. A metallic bridge links the retention part and the obstructive part. The device is effective, discrete, functional and well-tolerated by the patient.

  20. X-ray PIV measurement of blood flow in deep vessels of a rat: An in vivo feasibility study

    Science.gov (United States)

    Park, Hanwook; Yeom, Eunseop; Lee, Sang Joon

    2016-01-01

    X-ray PIV measurement is a noninvasive approach to measure opaque blood flows. However, it is not easy to measure real pulsatile blood flows in the blood vessels located at deep position of the body, because the surrounding tissues significantly attenuate the contrast of X-ray images. This study investigated the effect of surrounding tissues on X-ray beam attenuation by measuring the velocity fields of blood flows in deep vessels of a live rat. The decrease in image contrast was minimized by employing biocompatible CO2 microbubbles as tracer particles. The maximum measurable velocity of blood flows in the abdominal aorta of a rat model was found through comparative examination between the PIV measurement accuracy and the level of image contrast according to the input flow rate. Furthermore, the feasibility of using X-ray PIV to accurately measure in vivo blood flows was demonstrated by determining the velocity field of blood flows in the inferior vena cava of a rat. This study may serve as a reference in conducting in vivo X-ray PIV measurements of pulsatile blood flows in animal disease models and investigating hemodynamic characteristics and circulatory vascular diseases.

  1. X-ray PIV measurement of blood flow in deep vessels of a rat: An in vivo feasibility study.

    Science.gov (United States)

    Park, Hanwook; Yeom, Eunseop; Lee, Sang Joon

    2016-01-18

    X-ray PIV measurement is a noninvasive approach to measure opaque blood flows. However, it is not easy to measure real pulsatile blood flows in the blood vessels located at deep position of the body, because the surrounding tissues significantly attenuate the contrast of X-ray images. This study investigated the effect of surrounding tissues on X-ray beam attenuation by measuring the velocity fields of blood flows in deep vessels of a live rat. The decrease in image contrast was minimized by employing biocompatible CO2 microbubbles as tracer particles. The maximum measurable velocity of blood flows in the abdominal aorta of a rat model was found through comparative examination between the PIV measurement accuracy and the level of image contrast according to the input flow rate. Furthermore, the feasibility of using X-ray PIV to accurately measure in vivo blood flows was demonstrated by determining the velocity field of blood flows in the inferior vena cava of a rat. This study may serve as a reference in conducting in vivo X-ray PIV measurements of pulsatile blood flows in animal disease models and investigating hemodynamic characteristics and circulatory vascular diseases.

  2. Rapid sealing and cutting of porcine blood vessels, ex vivo, using a high-power, 1470-nm diode laser.

    Science.gov (United States)

    Giglio, Nicholas C; Hutchens, Thomas C; Perkins, William C; Latimer, Cassandra; Ward, Arlen; Nau, William H; Fried, Nathaniel M

    2014-03-01

    Suture ligation with subsequent cutting of blood vessels to maintain hemostasis during surgery is time consuming and skill intensive. Energy-based electrosurgical and ultrasonic devices are often used to replace sutures and mechanical clips to provide rapid hemostasis and decrease surgery time. Some of these devices may create undesirably large collateral zones of thermal damage and tissue necrosis, or require separate mechanical blades for cutting. Infrared lasers are currently being explored as alternative energy sources for vessel sealing applications. In a previous study, a 1470-nm laser was used to seal vessels 1 to 6 mm in diameter in 5 s, yielding burst pressures of ∼500  mmHg. The purpose of this study was to provide vessel sealing times comparable with current energy-based devices, incorporate transection of sealed vessels, and demonstrate high vessel burst pressures to provide a safety margin for future clinical use. A 110-W, 1470-nm laser beam was transmitted through a fiber and beam shaping optics, producing a 90-W linear beam 3.0 by 9.5 mm for sealing (400  W/cm2), and 1.1 by 9.6 mm for cutting (1080  W/cm2). A two-step process sealed and then transected ex vivo porcine renal vessels (1.5 to 8.5 mm diameter) in a bench top setup. Seal and cut times were 1.0 s each. A burst pressure system measured seal strength, and histologic measurements of lateral thermal spread were also recorded. All blood vessels tested (n=55 seal samples) were sealed and cut, with total irradiation times of 2.0 s and mean burst pressures of 1305±783  mmHg. Additional unburst vessels were processed for histological analysis, showing a lateral thermal spread of 0.94±0.48  mm (n=14 seal samples). This study demonstrated that an optical-based system is capable of precisely sealing and cutting a wide range of porcine renal vessel sizes and, with further development, may provide an alternative to radiofrequency- and ultrasonic-based vessel sealing devices.

  3. Application of a diagnostic-therapeutic procedure using implant-supported dental prosthesis as a preventive therapy for candidiasis of upper gastrointestinal tract in complete denture users.

    Science.gov (United States)

    Majewski, S; Loster, B W; Macura, A B; Wisniewska, G; Sliwowski, Z; Mazurkiewicz-Janik, M; Konturek, S J

    2008-11-01

    Our previous studies demonstrated that the use of acrylic based prosthesis in edentulous patients had a direct impact on the increased incidence of oral mycosis and further episodes of mycosis in the digestive tract. This dependency is associated with formation of a space between the surface of the prostheses and adhering mucosal membrane, where a specific micro environment is being formed, which - as stated - creates a superior breeding ground mainly for microorganisms of the genus Candida.

  4. [A new objective clinical method in the evaluation of the status of blood flow in conjunctival vessels].

    Science.gov (United States)

    Polunin, G S; Pirogova, E P; Iarovaia, L D

    1989-01-01

    The suggested method for assessment of the blood aggregation characteristics in the conjunctival vessels is based on microdensitometry of the blood stream microphotographs. The method permits a graphic recording of the blood stream. The potentialities of the developed technique have been studied in comparison of the blood aggregation in patients with diabetic retinopathy and in normal subjects. The data evidence an increased coagulation activity of the blood in patients with diabetes mellitus vs. normal subjects, this correlating with the biochemical findings in examinations of these patients' hemostasis. The clinical method for assessment of the blood aggregation characteristics may be useful for the prognosis of the course of various diseases and for monitoring the treatment efficacy.

  5. PEG-albumin supraplasma expansion is due to increased vessel wall shear stress induced by blood viscosity shear thinning.

    Science.gov (United States)

    Sriram, Krishna; Tsai, Amy G; Cabrales, Pedro; Meng, Fantao; Acharya, Seetharama A; Tartakovsky, Daniel M; Intaglietta, Marcos

    2012-06-15

    We studied the extreme hemodilution to a hematocrit of 11% induced by three plasma expanders: polyethylene glycol (PEG)-conjugated albumin (PEG-Alb), 6% 70-kDa dextran, and 6% 500-kDa dextran. The experimental component of our study relied on microelectrodes and cardiac output to measure both the rheological properties of plasma-expander blood mixtures and nitric oxide (NO) bioavailability in vessel walls. The modeling component consisted of an analysis of the distribution of wall shear stress (WSS) in the microvessels. Our experiments demonstrated that plasma expansion with PEG-Alb caused a state of supraperfusion with cardiac output 40% above baseline, significantly increased NO vessel wall bioavailability, and lowered peripheral vascular resistance. We attributed this behavior to the shear thinning nature of blood and PEG-Alb mixtures. To substantiate this hypothesis, we developed a mathematical model of non-Newtonian blood flow in a vessel. Our model used the Quemada rheological constitutive relationship to express blood viscosity in terms of both hematocrit and shear rate. The model revealed that the net effect of the hemodilution induced by relatively low-viscosity shear thinning PEG-Alb plasma expanders is to reduce overall blood viscosity and to increase the WSS, thus intensifying endothelial NO production. These changes act synergistically, significantly increasing cardiac output and perfusion due to lowered overall peripheral vascular resistance.

  6. Molecular Dynamics Simulation of Soft Grains: Malaria-Infected Red Blood Cells Motion within Obstructed 2-D Capillary Vessel

    CERN Document Server

    Haris, Luman; Haryanto, Freddy; Viridi, Sparisoma

    2013-01-01

    Molecular dynamics has been widely used to numerically solve equation of motion of classical many-particle system. It can be used to simulate many systems including biophysics, whose complexity level is determined by the involved elements. Based on this method, a numerical model had been constructed to mimic the behaviour of malaria-infected red blood cells within capillary vessel. The model was governed by three forces namely Coulomb force, normal force, and Stokes force. By utilizing two dimensional four-cells scheme, theoretical observation was carried out to test its capability. Although the parameters were chosen deliberately, all of the quantities were given arbitrary value. Despite this fact, the results were quite satisfactory. Combined with the previous results, it can be said that the proposed model were sufficient enough to mimic the malaria-infected red blood cells motion within obstructed capillary vessel. Keywords: molecular dynamics, two-dimensional model, red-blood cell motion, malaria

  7. Bioelectronic retinal prosthesis

    Science.gov (United States)

    Weiland, James D.

    2016-05-01

    Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

  8. Intraoral-extraoral combination prosthesis: improving retention using interconnecting magnets.

    Science.gov (United States)

    Engelen, Marloes; van Heumen, Celeste C M; Merkx, Matthias A W; Meijer, Gert J

    2014-01-01

    Osseointegrated implants have been well documented for retaining an obturator prosthesis as well as a facial prosthesis. However, when the defect extends to both the facial area and the maxilla, it is difficult to rehabilitate those defects to the satisfaction of the patient, especially in cases where implants cannot be placed on both sites. This case report describes the use of magnets to connect two prostheses, thereby increasing retention and patient comfort.

  9. Transport of membrane-bound mineral particles in blood vessels during chicken embryonic bone development.

    Science.gov (United States)

    Kerschnitzki, Michael; Akiva, Anat; Ben Shoham, Adi; Koifman, Naama; Shimoni, Eyal; Rechav, Katya; Arraf, Alaa A; Schultheiss, Thomas M; Talmon, Yeshayahu; Zelzer, Elazar; Weiner, Stephen; Addadi, Lia

    2016-02-01

    During bone formation in embryos, large amounts of calcium and phosphate are taken up and transported to the site where solid mineral is first deposited. The initial mineral forms in vesicles inside osteoblasts and is deposited as a highly disordered calcium phosphate phase. The mineral is then translocated to the extracellular space where it penetrates the collagen matrix and crystallizes. To date little is known about the transport mechanisms of calcium and phosphate in the vascular system, especially when high transport rates are needed and the concentrations of these ions in the blood serum may exceed the solubility product of the mineral phase. Here we used a rapidly growing biological model, the chick embryo, to study the bone mineralization pathway taking advantage of the fact that large amounts of bone mineral constituents are transported. Cryo scanning electron microscopy together with cryo energy dispersive X-ray spectroscopy and focused-ion beam imaging in the serial surface view mode surprisingly reveal the presence of abundant vesicles containing small mineral particles in the lumen of the blood vessels. Morphologically similar vesicles are also found in the cells associated with bone formation. This observation directly implicates the vascular system in solid mineral distribution, as opposed to the transport of ions in solution. Mineral particle transport inside vesicles implies that far larger amounts of the bone mineral constituents can be transported through the vasculature, without the danger of ectopic precipitation. This introduces a new stage into the bone mineral formation pathway, with the first mineral being formed far from the bone itself.

  10. Blood vessels and desmin control the positioning of nuclei in skeletal muscle fibers.

    Science.gov (United States)

    Ralston, E; Lu, Z; Biscocho, N; Soumaka, E; Mavroidis, M; Prats, C; Lømo, T; Capetanaki, Y; Ploug, T

    2006-12-01

    Skeletal muscle fibers contain hundreds to thousands of nuclei which lie immediately under the plasmalemma and are spaced out along the fiber, except for a small cluster of specialized nuclei at the neuromuscular junction. How the nuclei attain their positions along the fiber is not understood. Here we show that the nuclei are preferentially localized near blood vessels (BV), particularly in slow-twitch, oxidative fibers. Thus, in rat soleus muscle fibers, 81% of the nuclei appear next to BV. Lack of desmin markedly perturbs the distribution of nuclei along the fibers but does not prevent their close association with BV. Consistent with a role for desmin in the spacing of nuclei, we show that denervation affects the organization of desmin filaments as well as the distribution of nuclei. During chronic stimulation of denervated muscles, new BV form, along which muscle nuclei align themselves. We conclude that the positioning of nuclei along muscle fibers is plastic and that BV and desmin intermediate filaments each play a distinct role in the control of this positioning.

  11. MODIFICATION OF THE NUSS PROCEDURE-PREVENTION OF INJURIES OF THE HEART AND MAJOR BLOOD VESSELS

    Directory of Open Access Journals (Sweden)

    Mirko Žganjer

    2012-09-01

    Full Text Available Objective: The Nuss procedure is a widely accepted technique for correcting pectus excavatum. Unfortunately, fatal complications such as cardiac perforation and injury of the great blood vessels have been noticed in a few patients.We modified original Nuss technique to be simpler and lessdangerous.Methods: We modified Nuss procedure with the sternal elevation to improve sternal depression. Modified Nuss procedure was carried out by applying metal lifter raise sterum until the patient starts to raise from the operating table. The space behind sternum is now wider, and surgeryhas become safer with less probability of injuries intrathoracic organs. We compared 46 patients operated by the original Nuss method (taking into account the data from the literature on complications of the original method on a large series of patients with 54 patients operated by a modified Nuss method.Results: Before lifting the sternum depth of the deformity was between 2.9 and 6.2 cm (mean 5.4 cm, and the increase were between 1.5 and 4.0 cm (mean 2.8 cm. The difference of 2.6 cm is large enough, and the width of introducer and bars are about 3 mm for securely passed along the chest.Conclusions: A modified method of treating pectus excavatum is safer, better and with fewer complications than the original method of Nuss.

  12. Possible bi-directional link between ETA receptors and protein kinase C in rat blood vessels

    Directory of Open Access Journals (Sweden)

    A. M. Northover

    1995-01-01

    Full Text Available Possible links have been investigated between activation of protein kinase C (PKC and endothelin (ET production by small blood vessels. Perfusion pressures were recorded from rat isolated mesenteric artery, with or without the small intestine attached, before and after addition to the perfusate of either ET-1, ET-3 or the PKC activator 12-deoxyphorbol 13-phenylacetate (DOPPA. Rises in perfusion pressure in response to ET-1 (10−8 Mor DOPPA (10−6 M were reduced significantly by pre-treatment with either the ETA receptor antagonist PD151242 (10−6 M or the PKC inhibitor Ro 31-8220 (10−6 M. ET-3 (10−8 M had a significant, albeit small, effect only when the gut was still attached to the mesentery. Inthis latter preparation ET-1 and DOPPA increased the permeability of villi microvessels to colloidal carbon in the perfusate. This effect of DOPPA was reduced by pre-treatment with either PD151242 or Ro 31-8220, but the effects of ET-1 were reduced significantly only by Ro 31-8220. ET-3 (10−8 M was without effect. The results suggest a possible bi-directional link between ETA receptors and PKC in the intestinal vasculature.

  13. Infrared tomography for diagnostic imaging of port wine stain blood vessels

    Energy Technology Data Exchange (ETDEWEB)

    Goodman, D. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    The objective of this work is the development of Infrared Tomography (IRT) for detecting and characterizing subsurface chromophores in human skin. Characterization of cutaneous chromophores is crucial for advances in the laser treatment of pigmented lesions (e.g., port wine stain birthmarks and tatoos). Infrared tomography (IRT) uses a fast infrared focal plane array (IR-FPA) to detect temperature rises in a substrate induced by pulsed radiation. A pulsed laser is used to produce transient heating of an object. The temperature rise, due to the optical absorption of the pulsed laser light, creates an increase in infrared emission which is measured by the IR-FPA. Although the application of IRT to image subsurface cracks due to metal fatigue is a topic of great interest in the aircraft industry, the application to image subsurface chromophores in biological materials is novel. We present an image recovery method based on a constrained conjugate gradient algorithm that has obtained the first ever high quality images of port wine blood vessels.

  14. Thermal expansion of vitrified blood vessels permeated with DP6 and synthetic ice modulators.

    Science.gov (United States)

    Eisenberg, David P; Taylor, Michael J; Jimenez-Rios, Jorge L; Rabin, Yoed

    2014-06-01

    This study provides thermal expansion data for blood vessels permeated with the cryoprotective cocktail DP6, when combined with selected synthetic ice modulators (SIMs): 12% polyethylene glycol 400, 6% 1,3-cyclohexanediol, and 6% 2,3-butanediol. The general classification of SIMs includes molecules that modulate ice nucleation and growth, or possess properties of stabilizing the amorphous state, by virtue of their chemical structure and at concentrations that are not explained on a purely colligative basis. The current study is part of an ongoing effort to characterize thermo-mechanical effects on structural integrity of cryopreserved materials, where thermal expansion is the driving mechanism to thermo-mechanical stress. This study focuses on the lower part of the cryogenic temperature range, where the cryoprotective agent (CPA) behaves as a solid for all practical applications. By combining results obtained in the current study with literature data on the thermal expansion in the upper part of the cryogenic temperature range, unified thermal expansion curves are presented.

  15. VIP-CT瓣在美学区即刻种植即刻修复中的临床应用%Clinical research of VIP-CT flap in immediate implant and immediate prosthesis in aesthetic zone

    Institute of Scientific and Technical Information of China (English)

    宁晔; 吴海珍; 陆钰; 胡芳芳; 康林; 王群

    2016-01-01

    目的 探讨采用血管化骨膜-结缔组织夹层(VIP-CT)瓣在美学区即刻种植即刻修复中的临床效果.方法 选择合适的上颌前牙区单牙微创拔牙后即刻种植即刻修复患者共30例,均采用VIP-CT瓣关闭拔牙创口,制作临时冠诱导牙龈成形,且术后3个月左右行最终修复.修复完成后当天、6个月及12个月,以粉红美学指数(PES)对种植体周围软组织进行美学评价;同时以视觉模拟评分法(VAS)对患者进行主观满意度调查.结果 在追踪评估期间内,2例患者未按时复诊退出评估,剩余28例患者各时期的PES评分分别为(12.23±1.56)、(11.47±1.42)和(11.35±1.21)分,术后创面均完全封闭,唇侧丰满度较好,种植体周围软组织形态恢复正常,患者满意度较高.结论 在美学区即刻种植即刻修复中采用VIP-CT瓣可以获得良好的美学修复效果.%Objective To study the clinical effect of vascularized inter-positional periosteal-connective tissue(VIP-CT flap)on the aesthetic area immediately implanted and immediately prosthesis .Methods A total of 30 patients with minimally invasive tooth extraction im-mediately after implant of single tooth and immediate prosthesis in maxillary anterior teeth area were chosen ,VIP-CT flap was adopted in clos-ing tooth extraction wound , temporary crowns were made to induce gum forming ,and the final repair was performed postoperative 3 months. After completion of repair on the very day ,6 months and 12 months,pink aesthetic score(PES)was used to evaluate aesthetically the soft tis-sue around the implant.At the same time,the method of visual analogue scale (VAS)was carried out to investigate the subjective satisfaction of the patients.Results During the period of tracking assessment ,two patients who did not visit exited the evaluation ,PES grading of 28 pa-tients in each period was respectively (12.23 ±1.56),(11.47 ±1.42),(11.35 ±1.21).The postoperative wounds were completely closed , labial

  16. Custom ocular prosthesis: A palliative approach

    Directory of Open Access Journals (Sweden)

    Prachi Thakkar

    2015-04-01

    Full Text Available The goal of palliative care is the achievement of the best quality of life for patients and their families. Eyes are generally the first features of the face to be noticed. Loss of an eye is a traumatic event which has a crippling effect on the psychology of the patient. Several ocular and orbital disorders require surgical intervention that may result in ocular defects. An ocular prosthesis is fabricated to restore the structure, function, and cosmetics of the defects created by such conditions. Although an implant eye prosthesis has a superior outcome, due to economic factors it may not be a feasible option for all patients. Therefore, a custom-made ocular prosthesis is a good alternative. This case report presents a palliative treatment for a patient with an enucleated eye by fabricating a custom ocular prosthesis which improved his psychological, physical, social, functional, emotional and spiritual needs.

  17. Estudo experimental do implante transcateter de prótese valvada autoexpansível na via de saída do ventrículo direito em porcos Transcatheter implantation of self-expandable valved prosthesis in outlet right ventricle an experimental study in pigs

    Directory of Open Access Journals (Sweden)

    José Cícero Stocco Guilhen

    2011-09-01

    right heart failure with clinical deterioration. These children require multiple interventions throughout their lives, which impose a high rate of morbidity and mortality. OBJECTIVE: To develop a less invasive technique for implantation of a valved prosthesis through the right ventricle. METHODS: The valved prosthesis consists of an auto expanding metal stent built with nitinol, surrounded with polyester, where the three leaflets of bovine pericardium were mounted. Twelve pigs were used to perform the implants. Echocardiographic control was performed immediately after implantation and one, four, eight and 12 weeks. RESULTS: One animal showed reflux of moderate to severe and three mild reflux. Transvalvular gradients measured before implantation ranged from 3 to 6 mmHg and that soon after the implant was increased, ranging from 7 to 45 mmHg. There was a decrease in these gradients during follow up and in only four of the twelve animals the gradients were above 20 mmHg. Thrombus formation occurred in the prosthesis of six animals, and this was the most frequent complication. CONCLUSION: These findings highlight the need for studies with the use of anticoagulants and antiplatelet, an attempt to reduce this event. The study aims to contribute for the start of the use of prosthetic heart valves that could be implanted through minimally invasive techniques without the use of cardiopulmonary bypass

  18. Conus hip prosthesis.

    Science.gov (United States)

    Wagner, H; Wagner, M

    2001-01-01

    50 years ago, prosthetic replacement of the hip joint ushered in a new epoch in orthopaedics. Total hip replacement made it possible to remove a severely diseased, painful hip and restore normal function and a normal quality of life to the afflicted patient. The early results of total hip replacement are almost all spectacular and hip replacement has become the most successful type of orthopaedic surgery. These good results using an approach that was technically relatively simple resulted in a temptation to implant prosthetic hip joints with ever increasing frequency in ever younger patients. This led to the emergence of new problems, which were not so clearly recognised at the outset: it emerged that the stability of prosthetic hip joints was of limited duration. This had the following consequence: If a total hip prosthesis is implanted in an elderly person whose remaining life-expectancy is shorter than the longevity of the prosthesis, hip replacement is a life-long solution. We can therefore say that, for a patient who has only 10 to 15 years left to live, their hip problem is solved by total hip replacement. For young people, who still have a long life expectancy in front of them, it is different. They will experience failure of the artificial joint and require further surgery. The commonest and most important type of failure in total hip prostheses is aseptic loosening, which is associated with resorption of bone at the site of the prosthesis. The cause of this phenomenon has only gradually been recognised in the course of the years. Initially, the unanimous opinion was that the methacrylate cement, used to fix the components of the prosthesis in the bone, was the definitive cause of aseptic loosening because fissures and fractures of the cement were almost always found during surgical revision of loosened joints. There was talk of "cement disease" and great efforts were made to improve the quality of the cement and the cementing technique. Moreover, even

  19. Malformation of certain brain blood vessels caused by TCDD activation of Ahr2/Arnt1 signaling in developing zebrafish

    Energy Technology Data Exchange (ETDEWEB)

    Teraoka, Hiroki, E-mail: hteraoka@rakuno.ac.jp [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501 (Japan); Ogawa, Akira [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501 (Japan); Kubota, Akira [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501 (Japan); Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA (United States); Stegeman, John J. [Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA (United States); Peterson, Richard E. [School of Pharmacy, University of Wisconsin, Madison, WI (United States); Hiraga, Takeo [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu 069-8501 (Japan)

    2010-08-15

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes various signs of toxicity in early life stages of vertebrates through activation of the aryl hydrocarbon receptor (AHR). The AHR also plays important roles in normal development in mice, and AHR{sup -/-} mice show abnormal development of vascular structures in various blood vessels. Our previous studies revealed that Ahr type 2 (Ahr2) activation by TCDD and {beta}-naphthoflavone (BNF) caused a significant decrease in blood flow in the dorsal midbrain of zebrafish embryos. Here we report effects of TCDD exposure on the morphology of some blood vessels in the head of developing zebrafish. TCDD caused concentration-dependent anatomical rearrangements in the shape of the prosencephalic artery in zebrafish larvae. In contrast, no major vascular defects were recognized in the trunk and tail regions following exposure to TCDD at least at the concentrations used. Essentially, the same observations were also confirmed in BNF-exposed larvae. Knock-down of either Ahr2 or Ahr nuclear translocator type 1 (Arnt1) by morpholino oligonucleotides (MOs) protected larvae against abnormal shape of the prosencephalic artery caused by TCDD and BNF. On the other hand, knock-down of Ahr2 or Arnt1 in vehicle-exposed zebrafish larvae had no clear effect on morphology of the prosencephalic artery or trunk vessels. Ascorbic acid, an antioxidant, protected against the TCDD-induced decrease in blood flow through the prosencephalic artery, but not the abnormal morphological changes in the shape of this artery. These results indicate that activation of Ahr2/Arnt1 pathway by TCDD and BNF affects the shape of certain blood vessels in the brain of developing zebrafish.

  20. Analysis by NASA's VESGEN Software of Retinal Blood Vessels Before and After 70-Day Bed Rest: A Retrospective Study

    Science.gov (United States)

    Raghunandan, Sneha; Vyas, Ruchi J.; Vizzeri, Gianmarco; Taibbi, Giovanni; Zanello, Susana B.; Ploutz-Snyder, Robert; Parsons-Wingerter, Patricia A.

    2016-01-01

    Significant risks for visual impairment associated with increased intracranial pressure (VIIP) are incurred by microgravity spaceflight, especially long-duration missions. Impairments include decreased near visual acuity, posterior globe flattening, choroidal folds, optic disc edema and cotton wool spots. We hypothesize that microgravity-induced fluid shifts result in pathological changes within the retinal blood vessels that precede development of visual and other ocular impairments. Potential contributions of retinal vascular remodeling to VIIP etiology are therefore being investigated by NASAs innovative VESsel GENeration Analysis (VESGEN) software for two studies: (1) head-down tilt in human subjects before and after 70 days of bed rest, and (2) U.S. crew members before and after ISS missions. VESGEN analysis in previous research supported by the US National Institutes of Health identified surprising new opportunities to regenerate retinal vessels during early-stage, potentially reversible progression of the visually impairing and blinding disease, diabetic retinopathy.

  1. Numerical analysis of an osseointegrated prosthesis fixation with reduced bone failure risk and periprosthetic bone loss

    NARCIS (Netherlands)

    Tomaszewski, P. M.; van Diest, M.; Bulstra, S. K.; Verdonschot, N.; Verkerke, G. J.

    2012-01-01

    Currently available implants for direct attachment of prosthesis to the skeletal system after transfemoral amputation (OPRA system. Integrum AB, Sweden and ISP Endo/Exo prosthesis, ESKA Implants AG, Germany) show many advantages over the conventional socket fixation. However, restraining biomechanic

  2. Numerical analysis of an osseointegrated prosthesis fixation with reduced bone failure risk and periprosthetic bone loss.

    NARCIS (Netherlands)

    Tomaszewski, P.K.; Diest, M. van; Bulstra, S.K.; Verdonschot, N.J.; Verkerke, G.J.

    2012-01-01

    Currently available implants for direct attachment of prosthesis to the skeletal system after transfemoral amputation (OPRA system, Integrum AB, Sweden and ISP Endo/Exo prosthesis, ESKA Implants AG, Germany) show many advantages over the conventional socket fixation. However, restraining biomechanic

  3. In vitro evaluation of elastic multiblock co-polymers as a scaffold material for reconstruction of blood vessels.

    Science.gov (United States)

    Tzoneva, Rumiana; Weckwerth, Claudia; Seifert, Barbara; Behl, Marc; Heuchel, Matthias; Tsoneva, Iana; Lendlein, Andreas

    2011-01-01

    There is a need to create cell- and histocompatible implant materials, which might temporarily replace the mechanical function of a native tissue for regenerative therapies. To match the elastic behavior of the native tissue two different multiblock co-polymers were investigated: PDC, consisting of poly(p-dioxanone) (PPDO)/poly(ε-caprolactone) (PCL), and PDD, based on PPDO/poly((adipinate-alt-1,4-butanediol)-co-(adipinate-alt-ethylene glycol)-co-adipinate-alt-diethylene glycol) (Diorez). PDC is capable of a shapememory effect. Both multiblock co-polymers show an improved elasticity compared to materials applied in established vascular prosthesis. PDD is softer than PDC at 20°C, while PDC maintains its elasticity at 37°C. Thermodynamic characteristics indicate a more polar surface of PDD. Low cell adhesion was found on surfaces with low molar free energy of hysteresis (ΔG) derived from contact angle measurements in wetting and dewetting mode and high cell adhesion on high-ΔG surfaces. An increasing content of PCL in PDC improved cell adhesion and spreading of human umbilical vein endothelial cells. The prothrombotic potential of PDD is higher than PDC. Finally, it is concluded that PDC is a promising material for vascular tissue engineering because of its improved elastic properties, as well as balanced prothrombotic and anti-thrombotic properties with endothelial cells.

  4. Integrin-α5β1 is not required for mural cell functions during development of blood vessels but is required for lymphatic-blood vessel separation and lymphovenous valve formation.

    Science.gov (United States)

    Turner, Christopher J; Badu-Nkansah, Kwabena; Crowley, Denise; van der Flier, Arjan; Hynes, Richard O

    2014-08-15

    Integrin α5β1 is essential for vascular development but it remains unclear precisely where and how it functions. Here, we report that deletion of the gene encoding the integrin-α5 subunit (Itga5) using the Pdgfrb-Cre transgenic mouse line, leads to oedema, haemorrhage and increased levels of embryonic lethality. Unexpectedly, these defects were not caused by loss of α5 from Pdgfrb-Cre expressing mural cells (pericytes and vascular smooth muscle cells), which wrap around the endothelium and stabilise blood vessels, nor by defects in the heart or great vessels, but were due to abnormal development of the lymphatic vasculature. Reminiscent of the pathologies seen in the human lymphatic malformation, fetal cystic hygroma, α5 mutants display defects both in the separation of their blood and lymphatic vasculature and in the formation of the lymphovenous valves. As a consequence, α5-deficient mice develop dilated, blood-filled lymphatic vessels and lymphatic capillaries that are ectopically covered with smooth muscle cells. Analysis of the expression of Pdgfrb during lymphatic development suggests that these defects probably arise from loss of α5β1 integrin in subsets of specialised Prox1(+)Pdgfrb(+) venous endothelial cells that are essential for the separation of the jugular lymph sac from the cardinal vein and formation of the lymphovenous valve leaflets.

  5. Dual beam Doppler FD-OCT system with integrated Dynamic Vessel Analyzer and rotatable beams to measure total retinal blood flow

    Science.gov (United States)

    Doblhoff-Dier, Veronika; Werkmeister, René M.; Gröschl, Martin; Schmetterer, Leopold

    2014-03-01

    We present a method capable of measuring the total retinal blood flow in arteries and veins based on dual beam Fourierdomain Doppler optical coherence tomography (OCT) in combination with a fundus camera based Dynamic Vessel Analyzer. Incorporating a Dynamic vessel analyzer into the system not only gives a live image of the fundus - it also allows determining the vessels' diameter precisely during the OCT measurement, which is necessary for the determination of the blood flow. While dual beam systems with fixed detection plane allow only vessels with certain orientations to be measured, the detection plane of our system can be rotated by 90°. This ensures that the blood's velocity can be measured in all vessels around the optic nerve head. The results of the total blood flow measurements are in the same range as previously published data. Additionally, the high degree of conformity between the measured venous and arterial flow corroborated the system's validity. For larger vessels, the logarithmic values of vessel diameter and blood flow were found to be related linearly with a regression coefficient of around 3, which is in accordance with Murray's law. For smaller vessels (diameter below 60 μm), the values diverge from the linear dependence. The high sensitivity and the good agreement with published data suggest a high potential for examining the retinal blood flow in patients with ocular diseases.

  6. Sonda RF per al seguiment no-invasiu d'implants mèdics (stents)

    OpenAIRE

    De Cabrera Estanyol, Ferran

    2015-01-01

    Stents are medical devices that are implanted inside blood vessels to restore partial occlusions (stenosis). These devices (Fig. 1) are made of a frame of filaments (usually metallic) following a geometry that allows the frame to expand when a radial pressure is exerted. To implant them, stents are crimped around inflatable balloon catheters which are used to position the stent at the vessel occlusion. Once properly placed, the balloon is inflated and the stent is fixed to the vessel wall, re...

  7. Argus II retinal prosthesis system: An update.

    Science.gov (United States)

    Rachitskaya, Aleksandra V; Yuan, Alex

    2016-09-01

    This review focuses on a description of the Argus II retinal prosthesis system (Argus II; Second Sight Medical Products, Sylmar, CA) that was approved for humanitarian use by the FDA in 2013 in patients with retinitis pigmentosa with bare or no light perception vision. The article describes the components of Argus II, the studies on the implant, and future directions.

  8. Short Implants: New Horizon in Implant Dentistry.

    Science.gov (United States)

    Jain, Neha; Gulati, Manisha; Garg, Meenu; Pathak, Chetan

    2016-09-01

    The choice of implant length is an essential factor in deciding the survival rates of these implants and the overall success of the prosthesis. Placing an implant in the posterior part of the maxilla and mandible has always been very critical due to poor bone quality and quantity. Long implants can be placed in association with complex surgical procedures such as sinus lift and bone augmentation. These techniques are associated with higher cost, increased treatment time and greater morbidity. Hence, there is need for a less invasive treatment option in areas of poor bone quantity and quality. Data related to survival rates of short implants, their design and prosthetic considerations has been compiled and structured in this manuscript with emphasis on the indications, advantages of short implants and critical biomechanical factors to be taken into consideration when choosing to place them. Studies have shown that comparable success rates can be achieved with short implants as those with long implants by decreasing the lateral forces to the prosthesis, eliminating cantilevers, increasing implant surface area and improving implant to abutment connection. Short implants can be considered as an effective treatment alternative in resorbed ridges. Short implants can be considered as a viable treatment option in atrophic ridge cases in order to avoid complex surgical procedures required to place long implants. With improvement in the implant surface geometry and surface texture, there is an increase in the bone implant contact area which provides a good primary stability during osseo-integration.

  9. Noninvasive deadbeat control of an implantable rotary blood pump: a simulation study.

    Science.gov (United States)

    Lim, E; Alomari, A H; Savkin, A V; Lovell, N H

    2009-01-01

    A deadbeat controller has been proposed for the control of pulsatile pump flow in an implantable rotary blood pump (IRBP). A lumped parameter model of the cardiovascular system, in combination with the stable dynamical models of pulsatile flow and differential pressure (head) estimation for the IRBP was used to evaluate the controller. Pump speed and current were used as the only measured variables of the control system. The control algorithm was tested using both constant and sinusoidal reference pump flow input, under healthy and heart failure conditions. Results showed that the controller is able to track the reference input with minimal error in the presence of model uncertainty.

  10. Biomimetic control of vascular smooth muscle cell morphology and phenotype for functional tissue-engineered small-diameter blood vessels.

    Science.gov (United States)

    Chan-Park, Mary B; Shen, Jin Ye; Cao, Ye; Xiong, Yun; Liu, Yunxiao; Rayatpisheh, Shahrzad; Kang, Gavin Chun-Wei; Greisler, Howard P

    2009-03-15

    Small-diameter blood vessel substitutes are urgently needed for patients requiring replacements of their coronary and below-the-knee vessels and for better arteriovenous dialysis shunts. Circulatory diseases, especially those arising from atherosclerosis, are the predominant cause of mortality and morbidity in the developed world. Current therapies include the use of autologous vessels or synthetic materials as vessel replacements. The limited availability of healthy vessels for use as bypass grafts and the failure of purely synthetic materials in small-diameter sites necessitate the development of a biological substitute. Tissue engineering is such an approach and has achieved promising results, but reconstruction of a functional vascular tunica media, with circumferentially oriented contractile smooth muscle cells (SMCs) and extracellular matrix, appropriate mechanical properties, and vasoactivity has yet to be demonstrated. This review focuses on strategies to effect the switch of SMC phenotype from synthetic to contractile, which is regarded as crucial for the engineering of a functional vascular media. The synthetic SMC phenotype is desired initially for cell proliferation and tissue remodeling, but the contractile phenotype is then necessary for sufficient vasoactivity and inhibition of neointima formation. The factors governing the switch to a more contractile phenotype with in vitro culture are reviewed.

  11. NUMERICAL SIMULATION OF HEMODYNAMICS IN THE HOST BLOOD VESSEL AND MICROVASCULAR NETWORK GENERATED FROM TUMOR-INDUCED ANGIOGENESIS

    Institute of Scientific and Technical Information of China (English)

    ZHAO Gai-ping; WU Jie; XU Shi-xiong; COLLINS M.W.; JIANG Yu-ping; WANG Jian

    2006-01-01

    Numerical simulation of hemodynamics under the combined effects of both the host blood vessel and the microvascular network,which is based on a 2-D tumor inside and outside vascular network generated from a discrete mathematical model of tumor-induced angiogenesis, is performed systemically. And a "microvascular network-transport across microvascular network-flow in interstitium" model is developed to study the flow in solid tumor. Simulations are carried out to examine the effects of the variations of the inlet Reynolds number in the host blood vessel, the hydraulic conductivity of the microvascular wall, and interstitial hydraulic conductivity coefficient on the fluid flow in tumor microcirculation. The results are consistent with data obtained in terms of physiology. These results may provide some theoretical references and the bases for further clinical experimental research.

  12. Anisotropic micro-sphere-based finite elasticity applied to blood vessel modelling

    Science.gov (United States)

    Alastrué, V.; Martínez, M. A.; Doblaré, M.; Menzel, A.

    2009-01-01

    A fully three-dimensional anisotropic elastic model for vascular tissue modelling is presented here. The underlying strain energy density function is assumed to additively decouple into volumetric and deviatoric contributions. A straightforward isotropic neo-Hooke-type law is used to model the deviatoric response of the ground substance, whereas a micro-structurally or rather micro-sphere-based approach will be employed to model the contribution and distribution of fibres within the biological tissue of interest. Anisotropy was introduced by means of the use of von Mises orientation distribution functions. Two different micro-mechanical approaches—a, say phenomenological, exponential ansatz, and a worm-like-chain-based formulation—are applied to the micro-fibres and illustratively compared. The passage from micro-structural contributions to the macroscopic response is obtained by a computational homogenisation scheme, namely numerical integration over the surface of the individual micro-spheres. The algorithmic treatment of this integration is discussed in detail for the anisotropic problem at hand, so that several cubatures of the micro-sphere are tested in order to optimise the accuracy at reasonable computational cost. Moreover, the introduced material parameters are identified from simple tension tests on human coronary arterial tissue for the two micro-mechanical models investigated. Both approaches are able to recapture the experimental data. Based on the identified sets of parameters, we first discuss a homogeneous deformation in simple shear to evaluate the models' response at the micro-structural level. Later on, an artery-like two-layered tube subjected to internal pressure is simulated by making use of a non-linear finite element setting. This enables to obtain the micro- and macroscopic responses in an inhomogeneous deformation problem, namely a blood vessel representative boundary value problem. The effect of residual stresses is additionally

  13. The roles of blood-derived macrophages and resident microglia in the neuroinflammatory response to implanted Intracortical microelectrodes

    Science.gov (United States)

    Ravikumar, Madhumitha; Sunil, Smrithi; Black, James; Barkauskas, Deborah S.; Haung, Alex Y.; Miller, Robert H.; Selkirk, Stephen M.; Capadona, Jeffrey R.

    2014-01-01

    Resident microglia and blood-borne macrophages have both been implicated to play a dominant role in mediating the neuroinflammatory response affecting implanted intracortical microelectrodes. However, the distinction between each cell type has not been demonstrated due to a lack of discriminating cellular markers. Understanding the subtle differences of each cell population in mediating neuroinflammation can aid in determining the appropriate therapeutic approaches to improve microelectrode performance. Therefore, the goal of this study is to characterize the role of infiltrating blood-derived cells, specifically macrophages, in mediating neuroinflammation following intracortical microelectrode implantation. Interestingly, we found no correlation between microglia and neuron populations at the microelectrode-tissue interface. On the other hand, blood-borne macrophages consistently dominated the infiltrating cell population following microelectrode implantation. Most importantly, we found a correlation between increased populations of blood-derived cells (including the total macrophage population) and neuron loss at the microelectrode-tissue interface. Specifically, the total macrophage population was greatest at two and sixteen weeks post implantation, at the same time points when we observed the lowest densities of neuronal survival in closest proximity to the implant. Together, our results suggest a dominant role of infiltrating macrophages, and not resident microglia, in mediating neurodegeneration following microelectrode implantation. PMID:24973296

  14. About a mechanism of the influence of shear stress for viscosity of the blood in vessels of small diameter

    Directory of Open Access Journals (Sweden)

    Лев Николаевич Катюхин

    2014-12-01

    Full Text Available It is proposed a physiological and experimentally confirmed explanation of Fåhraeus-Lindqvist-effect in capillaries using the profile analyses of osmotic deformability of red blood cells. It was shown the dose-dependent change of the erythrocytes deformability in the stage of isotropic spheres after forming artificial water pores (nystatin and occlusion (PbCl2 of available pores. The Sigma-effect reducing of hematocrit and viscosity in a shear flow of blood through the vessels of a small diameter was conditioned by the interchange of liquid phase between the erythrocyte and the plasma.

  15. Clinical Observation on CAD/CAM Zirconia Ceramic Crowns in 50 Cases of the Implant Prosthesis%CAD/CAM氧化锆全瓷冠在50例种植修复中的临床观察

    Institute of Scientific and Technical Information of China (English)

    康振中; 唐吉飞

    2013-01-01

    目的 探讨CAD/CAM氧化锆全瓷冠在50例种植修复中的临床效果.方法 选取种植术后患者50例,共72颗缺失牙.采用CAD/CAM氧化锆全瓷冠修复,随访3a,了解患者全瓷冠完整情况和冠周情况.结果 经3a随访观察发现,50例患者72颗修复体中,2颗修复体周围有轻微炎症,治疗后痊愈.3颗后牙修复体瓷面破损,其余修复体均正常,失败率为4.2%.结论 采用CAD/CAM氧化锆全瓷冠进行种植修复可取得良好效果.%Objective To evaluate the clinical effect of CAD/CAM zirconia ceramic crowns in 50 cases of prosthesis.Method 50 cases with 72 missing teeth after planting operation were fixed with CAD/CAM allceramic crowns.There were 72 missing teeth.All patients were followed up 3 years,in which the intactness of zirconium porcelain crown and the status of gingival prosthesis were checked.Results 72 Missing teeth were fixed among 50 cases.It was found after the follow-up for 3 years that peripheral surfaces of 2 teeth were slightly inflammatory and recovered after treatment.The surfaces of 3 prostheses were damaged and the others were normal.The failure rate was 4.2%.Conclusion Adopting CAD/CAM zirconia ceramic crowns to repair implants teeth can achieve a better therapeutic effect.

  16. BLOOD VESSELS IN GANGLIA IN HUMAN ESOPHAGUS MIGHT EXPLAIN THE HIGHER FREQUENCY OF MEGAESOPHAGUS COMPARED WITH MEGACOLON

    Directory of Open Access Journals (Sweden)

    Sheila Jorge Adad

    2014-12-01

    Full Text Available This study aimed to determine the existence of blood vessels within ganglia of the myenteric plexus of the human esophagus and colon. At necropsy, 15 stillborns, newborns and children up to two years of age, with no gastrointestinal disorders, were examined. Rings of the esophagus and colon were analyzed and then fixed in formalin and processed for paraffin. Histological sections were stained by hematoxylin-eosin, Giemsa and immunohistochemistry for the characterization of endothelial cells, using antibodies for anti-factor VIII and CD31. Blood vessels were identified within the ganglia of the myenteric plexus of the esophagus, and no blood vessels were found in any ganglia of the colon. It was concluded that the ganglia of the myenteric plexus of the esophagus are vascularized, while the ganglia of the colon are avascular. Vascularization within the esophageal ganglia could facilitate the entrance of infectious agents, as well as the development of inflammatory responses (ganglionitis and denervation, as found in Chagas disease and idiopathic achalasia. This could explain the higher frequency of megaesophagus compared with megacolon.

  17. Modeling the Role of the Glymphatic Pathway and Cerebral Blood Vessel Properties in Alzheimer’s Disease Pathogenesis

    Science.gov (United States)

    Kyrtsos, Christina Rose; Baras, John S.

    2015-01-01

    Alzheimer’s disease (AD) is the most common cause of dementia in the elderly, affecting over 10% population over the age of 65 years. Clinically, AD is described by the symptom set of short term memory loss and cognitive decline, changes in mentation and behavior, and eventually long-term memory deficit as the disease progresses. On imaging studies, significant atrophy with subsequent increase in ventricular volume have been observed. Pathology on post-mortem brain specimens demonstrates the classic findings of increased beta amyloid (Aβ) deposition and the presence of neurofibrillary tangles (NFTs) within affected neurons. Neuroinflammation, dysregulation of blood-brain barrier transport and clearance, deposition of Aβ in cerebral blood vessels, vascular risk factors such as atherosclerosis and diabetes, and the presence of the apolipoprotein E4 allele have all been identified as playing possible roles in AD pathogenesis. Recent research has demonstrated the importance of the glymphatic system in the clearance of Aβ from the brain via the perivascular space surrounding cerebral blood vessels. Given the variety of hypotheses that have been proposed for AD pathogenesis, an interconnected, multilayer model offers a unique opportunity to combine these ideas into a single unifying model. Results of this model demonstrate the importance of vessel stiffness and heart rate in maintaining adequate clearance of Aβ from the brain. PMID:26448331

  18. Enhanced nestin expression and small blood vessels in human pituitary adenomas.

    Science.gov (United States)

    Perez-Millan, María Inés; Berner, Silvia Inés; Luque, Guillermina María; De Bonis, Cristian; Sevlever, Gustavo; Becu-Villalobos, Damasia; Cristina, Carolina

    2013-09-01

    The role of angiogenesis in human pituitary tumor progression is questioned. Our aim was to characterize the morphologic changes that occur in the vasculature of pituitary adenomas, in correlation with the expression of nestin, a protein found in endothelial cells of newly formed vessels of developing organs. We also evaluated the relation of angiogenic markers and nestin with Ki-67 index. Immunohistochemical studies were performed on paraffin embedded samples of 47 pituitary adenomas and six normal pituitaries. We determined microvessel density (number of CD31+ or CD34+ vessels per square millimetre), vascular area (cumulative area occupied by vessels), average vessel size, and further classified vessels as small ( 100 μm2). We correlated the above parameters with nestin expression and Ki-67 index. Lower vascular area compared to normal tissue was found in adenomas (p vessels than control pituitaries (p controls, so that nestin positive area was significantly higher in tumors. Furthermore, nestin area correlated positively with the % of small vessels. Ki-67 correlated neither with vascular area nor with nestin expression. In human pituitary tumors there was a predominance of small capillaries in correlation with increased expression of the progenitor marker nestin. We suggest that angiogenesis is an active process in these tumors, in spite of their low total vascular area when compared to normal pituitaries.

  19. The clinical treatment and follow-up study of inflatable penile prosthesis implantation%可膨胀阴茎支撑体植入术的临床治疗与随访研究

    Institute of Scientific and Technical Information of China (English)

    郭庆华; 张立元; 陈小勇

    2014-01-01

    目的:报告29例国产可膨胀阴茎支撑体植入术患者的手术治疗情况和远期疗效,以探讨其临床治疗价值。方法分析我院2002年至2013年行可膨胀阴茎支撑体植入手术治疗勃起功能障碍的患者29例,术后随访12~36个月,平均26个月,记录患者术后疗效及并发症情况,同时患者术后12个月门诊复诊,监测阴茎勃起硬度数值、手术前后进行国际勃起功能问卷(IIEF)评分,综合评价患者勃起功能和性生活满意度。结果29例ED患者手术均获成功,其中1例患者术后2月出现液泵阀失灵,半年后行二次植入手术,术后恢复良好;其余28例患者到目前研究,均未出现明显并发症。阴茎勃起硬度较术前有极显著增加(P<0.001),术后IIEF-5评分均较术前有极显著提高(P<0.001)。结论可膨胀阴茎支撑体植入术治疗男性勃起功能障碍手术成功率高,术后并发症少,性生活满意度高,手术安全可靠,值得临床推广。%Objective To report the operations treatment and the long-term curative effect of inflatable penile prosthesis implantation on 29 cases with erectile dysfunction.Methods Twenty-nine patients with erectile dysfunction underwent inflatable penile prosthesis implantation in our hospital from 2002 to 2013.Postoperative efficacy and complications in patients were recorded during 12~36 months (average 26 months) following up. All patients were required to monitor the hardness value of penile erectile after 12 months following up. The effects were observed based on IIEF of the patients before and after operation. The erectile function and the sexual satisfaction were evaluated comprehensively. Results All of the operations were successful. Only one patients developed pump failure, the other 28 patients had no obvious complications. There were very significant differences in the hardness values of penile erectile and all IIEF scores between before

  20. Manufacturer-provided effective orifice area index charts and the prevention of prosthesis-patient mismatch.

    Science.gov (United States)

    House, Chad M; Nelson, William B; Kroshus, Timothy J; Dahiya, Ranjan; Pibarot, Philippe

    2012-01-01

    Prosthesis-patient mismatch (PPM) occurs when an implanted prosthesis is too small relative to the patient's body surface area (BSA). However, mismatch can often be prevented by indexing the expected effective orifice area (EOA) of a prosthesis to the patient's BSA and then selecting the largest implantable prosthesis to avoid mismatch. Previously, prosthesis manufacturers have attempted to simplify this process by providing charts that include the expected EOA for their prosthesis, already indexed into an array of BSA values. One caveat with these charts is that the expected EOA data must truly be reliable, or the charts will misguide the implanting surgeon. Manufacturer-provided charts could be improved by standardizing the EOA data, with one potential source being the hemodynamic data submitted to the United States Food and Drug Administration. This review discusses PPM, manufacturer-provided EOA charts, and the regulation of EOA data.

  1. 21 CFR 888.3410 - Hip joint metal/polymer or ceramic/polymer semiconstrained resurfacing cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... semiconstrained resurfacing cemented prosthesis. 888.3410 Section 888.3410 Food and Drugs FOOD AND DRUG... prosthesis. (a) Identification. A hip joint metal/polymer or ceramic/polymer semi-constrained resurfacing cemented prosthesis is a two-part device intended to be implanted to replace the articulating surfaces...

  2. 21 CFR 888.3320 - Hip joint metal/metal semi-constrained, with a cemented acetabular component, prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented acetabular component, prosthesis. 888.3320 Section 888.3320 Food and Drugs FOOD AND DRUG..., prosthesis. (a) Identification. A hip joint metal/metal semi-constrained, with a cemented acetabular component, prosthesis is a two-part device intended to be implanted to replace a hip joint. The...

  3. 21 CFR 888.3353 - Hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented or nonporous uncemented prosthesis. 888.3353 Section 888.3353 Food and Drugs FOOD AND DRUG... prosthesis. (a) Identification. A hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis is a device intended to be implanted to replace a hip joint. This device...

  4. 21 CFR 888.3330 - Hip joint metal/metal semi-constrained, with an uncemented acetabular component, prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented acetabular component, prosthesis. 888.3330 Section 888.3330 Food and Drugs FOOD AND DRUG..., prosthesis. (a) Identification. A hip joint metal/metal semi-constrained, with an uncemented acetabular component, prosthesis is a two-part device intended to be implanted to replace a hip joint. The...

  5. Differential mechanisms associated with vascular disrupting action of electrochemotherapy: intravital microscopy on the level of single normal and tumor blood vessels.

    Directory of Open Access Journals (Sweden)

    Bostjan Markelc

    Full Text Available Electropermeabilization/electroporation (EP provides a tool for the introduction of molecules into cells and tissues. In electrochemotherapy (ECT, cytotoxic drugs are introduced into cells in tumors, and nucleic acids are introduced into cells in gene electrotransfer. The normal and tumor tissue blood flow modifying effects of EP and the vascular disrupting effect of ECT in tumors have already been determined. However, differential effects between normal vs. tumor vessels, to ensure safety in the clinical application of ECT, have not been determined yet. Therefore, the aim of our study was to determine the effects of EP and ECT with bleomycin on the HT-29 human colon carcinoma tumor model and its surrounding blood vessels. The response of blood vessels to EP and ECT was monitored in real time, directly at the single blood vessel level, by in vivo optical imaging in a dorsal window chamber in SCID mice with 70 kDa fluorescently labeled dextrans. The response of tumor blood vessels to EP and ECT started to differ within the first hour. Both therapies induced a vascular lock, decreased functional vascular density (FVD and increased the diameter of functional blood vessels within the tumor. The effects were more pronounced for ECT, which destroyed the tumor blood vessels within 24 h. Although the vasculature surrounding the tumor was affected by EP and ECT, it remained functional. The study confirms the current model of tumor blood flow modifying effects of EP and provides conclusive evidence that ECT is a vascular disrupting therapy with a specific effect on the tumor blood vessels.

  6. Evaluation of Mast Cell and Blood Vessel Density in Inflammatory Periapical Lesions

    Directory of Open Access Journals (Sweden)

    Safoura Seifi

    2012-01-01

    Full Text Available Introduction: Radicular cystsand periapical granulomas are the most common periapical inflammatory lesions. However, the role of cellular immunity and microvessels in their pathogenesis remains unknown. The aim of this study was to evaluate the mast cell density (MCD, mircovessel density (MVD and investigating the correlation between their densities with each other in the above mentioned lesions.Materials & Methods: In this descriptive cross-sectional study, 40 paraffin blocks of mentioned lesions were selected from achieves of School of Dentistry, Babol University of Medical Sciences. Three sections were prepared from each block and stained by hematoxylin-eosin, toluidine blue, and immunohistochemically for CD34 to determine the score of inflammation, presence of mast cells and degranulatedmast cells (DMCs, and MVD, respectively. The correlation between MCD and either inflammatory infiltrate or MVD was evaluated. Data analyzed by t student, Mann-Whitney and Spearman test.Results: Mast cells were present in all periapical inflammatory lesions; 15.4±14.8 for MCD, 7.2±6.1 for DMCs, and the ratio of DMCs to total number of MCs was 0.354±0.166 and 14.8+4.44 for blood vessel density in radicular cyst and 8.52±6.75, 2.91±2.1, 0.196±0.194 and 13±8.02 in periapical granulomas, respectively. There was a positive correlation between MCD and MVD in radicular cyst (P=0.03, r=0.341, but not in periapical granulomas (P=0.6, r=0.124. MCD and MVD increased with the score of inflammation in radicular cyst (P=0.001, r=0.7 and periapical granuloma (P=0.012, r=0.54.Conclusion: Mast cells and microvessels play a role in pathogenesis of periapical inflammatory lesions. In this study, the density of mast cells and DMCs in radicular cyst was higher than periapical granulomas, but no difference was observed regarding MVD in periapical inflammatory lesions. It seems that the relationship between MCD and MVD is different based on the clinical stage of periapical

  7. Noninvasive average flow estimation for an implantable rotary blood pump: a new algorithm incorporating the role of blood viscosity.

    Science.gov (United States)

    Malagutti, Nicolò; Karantonis, Dean M; Cloherty, Shaun L; Ayre, Peter J; Mason, David G; Salamonsen, Robert F; Lovell, Nigel H

    2007-01-01

    The effect of blood hematocrit (HCT) on a noninvasive flow estimation algorithm was examined in a centrifugal implantable rotary blood pump (iRBP) used for ventricular assistance. An average flow estimator, based on three parameters, input electrical power, pump speed, and HCT, was developed. Data were collected in a mock loop under steady flow conditions for a variety of pump operating points and for various HCT levels. Analysis was performed using three-dimensional polynomial surfaces to fit the collected data for each different HCT level. The polynomial coefficients of the surfaces were then analyzed as a function of HCT. Linear correlations between estimated and measured pump flow over a flow range from 1.0 to 7.5 L/min resulted in a slope of 1.024 L/min (R2=0.9805). Early patient data tested against the estimator have shown promising consistency, suggesting that consideration of HCT can improve the accuracy of existing flow estimation algorithms.

  8. Measurement of meningeal blood vessel diameter in vivo with a plug-in for ImageJ.

    Science.gov (United States)

    Fischer, Michael J M; Uchida, Sae; Messlinger, Karl

    2010-09-01

    Changes in blood vessel diameter can be measured manually, but this is time-consuming and often impractical. For automatic measurement commercial solutions are available, but the proprietary algorithms and their potential shortcomings are not known to the user. We present an approach with a CCD camera for image acquisition combined with free and open source ImageJ software for offline analysis. A subtraction image allows for the evaluation of the diameter changes throughout the field of view. A full width at half-maximum algorithm plug-in was written to measure the vessel diameter. For a given line across a vessel, the results of five measurements with parallel shifts throughout an image stack are copied to the clipboard. For validation of this method an established in vivo model was used, namely vascular changes in the rat dura mater, reflecting the activity of the afferent neurons. Vasoconstriction of the meningeal arterioles induced by local electrical stimulation of the dura was inhibited by intravenous administration of the adrenoceptor antagonist phentolamine and amplified by the CGRP receptor antagonist olcegepant. The described methods allow the user to quickly evaluate vessel diameter changes in the whole acquired field at any selected position.

  9. P/Q-type and T-type voltage-gated calcium channels are involved in the contraction of mammary and brain blood vessels from hypertensive patients

    DEFF Research Database (Denmark)

    Thuesen, A D; Lyngsø, K S; Rasmussen, L

    2017-01-01

    AIM: Calcium channel blockers are widely used in cardiovascular diseases. Besides L-type channels, T- and P/Q-type calcium channels are involved in the contraction of human renal blood vessels. It was hypothesized that T- and P/Q-type channels are involved in the contraction of human brain...... and mammary blood vessels. METHODS: Internal mammary arteries from bypass surgery patients and cerebral arterioles from patients with brain tumours with and without hypertension were tested in a myograph and perfusion set-up. PCR and immunohistochemistry were performed on isolated blood vessels. RESULTS......: The P/Q-type antagonist ω-agatoxin IVA (10(-8) mol L(-1) ) and the T-type calcium blocker mibefradil (10(-7) mol L(-1) ) inhibited KCl depolarization-induced contraction in mammary arteries from hypertensive patients with no effect on blood vessels from normotensive patients. ω-Agatoxin IVA decreased...

  10. Angiogenesis and vasculogenesis: inducing the growth of new blood vessels and wound healing by stimulation of bone marrow-derived progenitor cell mobilization and homing.

    Science.gov (United States)

    Velazquez, Omaida C

    2007-06-01

    During embryonic development, the vasculature is among the first organs to form and is in charge of maintaining metabolic homeostasis by supplying oxygen and nutrients and removing waste products. As one would expect, blood vessels are critical not only for organ growth in the embryo but also for repair of wounded tissue in the adult. An imbalance in angiogenesis (a time-honored term that globally refers to the growth of new blood vessels) contributes to the pathogenesis of numerous malignant, inflammatory, ischemic, infectious, immune, and wound-healing disorders. This review focuses on the central role of the growth of new blood vessels in ischemic and diabetic wound healing and defines the most current nomenclature that describes the neovascularization process in wounds. There are now two well-defined, distinct, yet interrelated processes for the formation of postnatal new blood vessels, angiogenesis, and vasculogenesis. Reviewed are recent new data on vasculogenesis that promise to advance the field of wound healing.

  11. [The effect of prostatilen on the contractile activity of the smooth-muscle cells of the blood vessels and bladder in cats].

    Science.gov (United States)

    al-Shchukri, S Kh; Barabanov, S V; Barabanova, V V; Bobkov, Iu A; Gorbachev, A G; Parastaeva, M M

    1996-07-01

    Prostatilene enhanced the functional activity of the bladder and blood vessels' smooth muscle cells. A possibility of activation of the smooth muscle cells contractility with prostatilene by a pharmaco-mechanical association, is discussed.

  12. Capitate pyrocarbon prosthesis in radiocarpal osteoarthritis.

    Science.gov (United States)

    Goubier, Jean-Noël; Vogels, Jérome; Teboul, Frédéric

    2011-03-01

    Scapholunate dissociation or scaphoid pseudarthrosis