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Sample records for experimental prosthetic graft

  1. Graft-Sparing Strategy for Thoracic Prosthetic Graft Infection.

    Science.gov (United States)

    Uchino, Gaku; Yoshida, Takeshi; Kakii, Bunpachi; Furui, Masato

    2018-04-01

     Thoracic prosthetic graft infection is a rare but serious complication with no standard management. We reported our surgical experience on graft-sparing strategy for thoracic prosthetic graft infection.  This study included patients who underwent graft-sparing surgery for thoracic prosthetic graft infection at Matsubara Tokushukai Hospital in Japan from January 2000 to October 2017.  There were 17 patients included in the analyses, with a mean age at surgery of 71.0 ± 10.5 years; 11 were men. In-hospital mortality was observed in five patients (29.4%).  Graft-sparing surgery for thoracic prosthetic graft infection is an alternative option particularly for early graft infection after hemiarch replacement. Georg Thieme Verlag KG Stuttgart · New York.

  2. [Localized purpura revealing vascular prosthetic graft infection].

    Science.gov (United States)

    Boureau, A S; Lescalie, F; Cassagnau, E; Clairand, R; Connault, J

    2013-07-01

    Prosthetic graft infection after vascular reconstruction is a rare but serious complication. We report a case of infection occurring late after implantation of an iliofemoral prosthetic vascular graft. The Staphylococcus aureus infection was revealed by vascular purpura localized on the right leg 7 years after implantation of a vascular prosthesis. This case illustrates an uncommonly late clinical manifestation presenting as an acute infection 7 years after the primary operation. In this situation, the presentation differs from early infection, which generally occurs within the first four postoperative months. Diagnosis and treatment remain a difficult challenge because prosthetic graft infection is a potentially life-threatening complication. Morbidity and mortality rates are high. Here we detail specific aspects of the clinical and radiological presentation. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  3. Salmonella Typhimurium gastroenteritis leading to chronic prosthetic vascular graft infection.

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    Cullinan, Milo; Clarke, Michael; Dallman, Tim; Peart, Steven; Wilson, Deborah; Weiand, Daniel

    2017-08-01

    Introduction. It is estimated up to 6 % of prosthetic vascular grafts become infected. Staphylococcus aureus is predominant in early infection and coagulase-negative staphylococci are predominant in late infections. Enterobacteriaceae cause 14-40 % of prosthetic vascular graft infections. This is, to our knowledge the first reported case of Salmonella gastroenteritis causing chronic prosthetic vascular graft infection (PVGI). Case presentation. A 57 years old lady presented with signs and symptoms of prosthetic vascular graft infection. Three years earlier, she had undergone a prosthetic axillo-femoral bypass graft for critical limb ischaemia. The infected prosthetic vascular graft was removed and Salmonella Typhimurium was isolated on culture. In the intervening period, Salmonella Typhimurium was isolated from a faecal specimen, collected during an episode of acute gastroenteritis. Whole-genome sequencing (WGS) showed that the respective Salmonella Typhimurium isolates differed by only a single nucleotide polymorphism (SNP). Salmonella Typhimurium was not isolated on culture of a faecal specimen collected five days following cessation of antimicrobial therapy. Six months after removal of the prosthetic graft, the patient remains under follow-up for her peripheral vascular disease, which currently requires no further surgical intervention. Conclusion. This case has clear implications for the management of chronic PVGI. It is vital to collect high-quality surgical specimens for microbiological analysis and empirical choices of antibiotics are unlikely to cover all potential pathogens. It may also be prudent to enquire about a history of acute gastroenteritis when assessing patients presenting with chronic PVGI.

  4. Prosthetic vascular graft infection and prosthetic joint infection caused by Pseudomonas stutzeri.

    Science.gov (United States)

    Bonares, Michael J; Vaisman, Alon; Sharkawy, Abdu

    2016-01-01

    Pseudomonas stutzeri is infrequently isolated from clinical specimens, and if isolated, more likely represents colonization or contamination rather than infection. Despite this, there are dozens of case reports which describe clinically significant P. stutzeri infections at variable sites. A 69-year-old man had a P. stutzeri infection of a prosthetic vascular graft infection, which he received in Panama City. He was successfully treated with a single antipseudomonal agent for 6 weeks and the removal of the infected vascular graft. A 70-year-old man had a P. stutzeri infection of a prosthetic joint, which was successfully treated with a single anti-pseudomonal agent for 6 weeks. There is only one other documented case of a prosthetic vascular graft infection secondary to P. stutzeri . There are 5 documented cases of P. stutzeri prosthetic joint infections. The previous cases were treated with antibiotics and variably, source control with the removal of prosthetic material. Most cases of P. stutzeri infection are due to exposure in health care settings. Immunocompromised states such as HIV or hematological and solid tumor malignancies are risk factors for P. stutzeri infection. Infections caused by P. stutzeri are far less frequent and less fatal than those caused by P. aeruginosa. The etiology of a P. stutzeri infection could be exposure to soil and water, but also contaminated material in the health care setting or an immunocompromised state. Iatrogenic infections that are secondary to health care tourism are a potential cause of fever in the returned traveler.

  5. Exophiala (Wangiella dermatitidis Prosthetic Aortic Valve Endocarditis and Prosthetic Graft Infection in an Immune Competent Patient

    Directory of Open Access Journals (Sweden)

    Jay S. Berger

    2017-01-01

    Full Text Available Exophiala (Wangiella dermatitidis is an emerging dematiaceous fungus associated with high mortality rates and is a rare cause of endocarditis. We describe the first case of E. dermatitidis endocarditis of a prosthetic aortic valve and aortic graft in an immune competent patient with no clear risk factors of hematological acquisition.

  6. Prosthetic graft infection: limitations of indium white blood cell scanning

    International Nuclear Information System (INIS)

    Brunner, M.C.; Mitchell, R.S.; Baldwin, J.C.; James, D.R.; Olcott, C. IV; Mehigan, J.T.; McDougall, I.R.; Miller, D.C.

    1986-01-01

    The lack of a rapid, noninvasive, and accurate method to confirm or rule out prosthetic graft infection continues to constitute a compelling and vexing clinical problem. A host of adjunctive diagnostic techniques has been used in the past, but early promising results subsequently have usually not yielded acceptable sensitivity (reflecting false negatives) and specificity (reflecting false positive) data. White blood cell (WBC) indium 111 scanning has recently been added to this list. The utility and accuracy of 111 In WBC scans were assessed by retrospective review of WBC scan results in 70 patients undergoing evaluation for possible prosthetic graft infection over a 7-year period. Operative and autopsy data (mean follow-up, 18 months for survivors with negative scans) were used to confirm the 22 positive, 45 negative, and three equivocal WBC scans. The false positive rate (+/- 70% confidence limits) was 36% +/- 6% (n = 8) among the 22 patients with positive scans (44% +/- 6% [11 of 25] if the three equivocal scans are included as false positive), yielding a specificity of 85% +/- 5% and an overall accuracy rate of 88% +/- 4% (80% +/- 5% and 84% +/- 5%, respectively, if the three equivocal cases are considered as false positive). All three patients with equivocal scans ultimately were judged not to have prosthetic graft infection. As implied by the high accuracy rate, the sensitivity of the test was absolute (100% [14 of 14]); there were no false negative results

  7. In vitro adherence of bacteria to prosthetic grafting materials

    International Nuclear Information System (INIS)

    Brewer, A.R.; Stromberg, B.V.

    1990-01-01

    Adherence of bacteria to prosthetic grafting material is thought to play an important role in the ultimate development of prosthetic infections. To evaluate the role of bacterial adherence in the initiation and colonization of prosthetic materials, Proplast II, Gore-Tex, and silicone were evaluated for adherence of Escherichia coli and Staphylococcus aureus. Bacteria were radiolabeled and incubated with the study material. Adherence was determined by scintillation. Adherence to Proplast II and Gore-Tex reached a maximum at approximately 45 minutes of incubation and demonstrated a detachment phenomenon with E. coli. Similar results were noted with S. aureus, but with a maximal attachment at approximately 30 minutes. Interestingly, bacterial attachment to silicone continued to increase throughout the time of the incubation. In addition, adherence of S. aureus was at a faster rate than E. coli. Attachment of bacteria is a multifactorial process. However, the PTFE graft demonstrates a slower rate of attachment, lower total number of attached bacteria, and faster detachment. The importance of this phenomenon may help explain the foreign body effect of increased susceptibility to infection of foreign materials

  8. Uptake of radiolabeled leukocytes in prosthetic graft infection

    International Nuclear Information System (INIS)

    Serota, A.I.; Williams, R.A.; Rose, J.G.; Wilson, S.E.

    1981-01-01

    The utility of radionuclide labeled leukocytes in the demonstration of infection within vascular prostheses was examined. The infrarenal aorta was replaced with a 3 cm Dacron graft in 12 dogs. On the third postoperative day, six of the animals received an intravenous injection of 10(8) Staphylococcus aureus. Labeled leukocyte scans were performed at postoperative days one and three, and then weekly for 8 weeks with indium-111 and technetium-99 labeled autologous leukocytes. When scans showed focal uptake of isotope in the area of prosthetic material, the grafts were aseptically excised and cultured on mannitol-salt agar. Both control and infected animals had retroperitoneal isotope activity in the immediate postoperative period that disappeared by the end of the first week. By the eighth postoperative week, all of the animals that received the bacteremic challenge had both radionuclide concentration in the region of the vascular prosthesis and S. aureus cultured subsequently from the perigraft tissues. None of the control animals had either radionuclide or bacteriologic evidence of infection at the eighth postoperative week. The radiolabeled leukocyte scan is a highly sensitive and specific technique, clinically applicable for the diagnosis of vascular prosthetic infections

  9. Diagnosis of arterial prosthetic graft infection by 111In oxine white blood cell scans

    International Nuclear Information System (INIS)

    McKeown, P.P.; Miller, D.C.; Jamieson, S.W.; Mitchell, R.S.; Reitz, B.A.; Olcott, C.; Mehigan, J.T.; Silberstein, R.J.; McDougall, I.R.

    1982-01-01

    Early and accurate diagnosis of infected prosthetic arterial grafts is difficult, despite the application of diverse diagnostic modalities. Delay in making the diagnosis is largely responsible for the high amputation and mortality rates associated with this complication. In nine patients with suspected graft infections, 111 In white blood cell scanning was useful and accurate. Graft infection was proved in five cases and ruled out in three. One false-positive scan was due to a sigmoid diverticular abscess overlying the graft. 111 In white blood cell scans may improve the accuracy of diagnosing infected prosthetic grafts, which may result in better limb and patient salvage rates

  10. Bio-absorbable antibiotic impregnated beads for the treatment of prosthetic vascular graft infections.

    Science.gov (United States)

    Genovese, Elizabeth A; Avgerinos, Efthymios D; Baril, Donald T; Makaroun, Michel S; Chaer, Rabih A

    2016-12-01

    There is limited investigation into the use of bio-absorbable antibiotic beads for the treatment of prosthetic vascular graft infections. Our goal was to investigate the rates of infection eradication, graft preservation, and limb salvage in patients who are not candidates for graft explant or extensive reconstruction. A retrospective review of patients implanted with antibiotic impregnated bio-absorbable calcium sulfate beads at a major university center was conducted. Six patients with prosthetic graft infections were treated with bio-absorbable antibiotics beads from 2012-2014. Grafts included an aortobifemoral, an aorto-hepatic/superior mesenteric artery, and four extra-anatomic bypasses. Pathogens included Gram-positive and Gram-negative bacteria. Half of the patients underwent graft explant with reconstruction and half debridement of the original graft, all with antibiotic bead placement around the graft. Mean follow-up was 7.3 ± 8.3 months; all patients had infection resolution, healed wounds, and 100% graft patency, limb salvage, and survival. This report details the successful use of bio-absorbable antibiotic beads for the treatment prosthetic vascular graft infections in patients at high risk for graft explant or major vascular reconstruction. At early follow-up, we demonstrate successful infection suppression, graft preservation, and limb salvage with the use of these beads in a subset of vascular patients. © The Author(s) 2016.

  11. Bio-absorbable antibiotic impregnated beads for the treatment of prosthetic vascular graft infections

    Science.gov (United States)

    Genovese, Elizabeth A; Avgerinos, Efthymios D; Baril, Donald T; Makaroun, Michel S; Chaer, Rabih A

    2017-01-01

    Objective There is limited investigation into the use of bio-absorbable antibiotic beads for the treatment of prosthetic vascular graft infections. Our goal was to investigate the rates of infection eradication, graft preservation, and limb salvage in patients who are not candidates for graft explant or extensive reconstruction. Methods A retrospective review of patients implanted with antibiotic impregnated bio-absorbable calcium sulfate beads at a major university center was conducted. Results Six patients with prosthetic graft infections were treated with bio-absorbable antibiotics beads from 2012–2014. Grafts included an aortobifemoral, an aorto-hepatic/superior mesenteric artery, and four extra-anatomic bypasses. Pathogens included Gram-positive and Gram-negative bacteria. Half of the patients underwent graft explant with reconstruction and half debridement of the original graft, all with antibiotic bead placement around the graft. Mean follow-up was 7.3±8.3 months; all patients had infection resolution, healed wounds, and 100% graft patency, limb salvage, and survival. Conclusion This report details the successful use of bio-absorbable antibiotic beads for the treatment prosthetic vascular graft infections in patients at high risk for graft explant or major vascular reconstruction. At early follow-up, we demonstrate successful infection suppression, graft preservation, and limb salvage with the use of these beads in a subset of vascular patients. PMID:26896286

  12. Prosthetic above-knee femoropopliteal bypass grafting: five-year results of a randomized trial.

    Science.gov (United States)

    Green, R M; Abbott, W M; Matsumoto, T; Wheeler, J R; Miller, N; Veith, F J; Money, S; Garrett, H E

    2000-03-01

    This trial was designed to identify factors affecting patency rates of primary prosthetic above-knee femoropopliteal bypass grafts at 5 years. A multi-institutional, prospective trial randomized 240 patients to compare patency rates of Gore-tex and Hemashield above-knee femoropopliteal bypass grafts at 5 years. Univariate comparisons of patency between levels of each prognostic variable were made with the Kaplan-Meier method. Variables that had a univariate P value less than.25 or those known to be important were submitted to a Cox regression analysis. The patient survival rate at 5 years was 59.4%. There were no differences in primary or secondary patency rates at 5 years between the two graft materials (primary, 45% vs 43% and secondary, 68% vs 68%). The risk for graft occlusion was significantly increased for patients younger than 65 years (2.1; P =.001) and for grafts with a diameter less than 7 mm (1.65; P =.0219). Variables with no apparent independent effect on patency rates were smoking status, runoff, diabetes mellitus, sex, presenting symptoms, and postoperative treatment with aspirin or Coumadin. Noninvasive test results were not predictive of subsequent graft function. Although the type of prosthetic used for above-knee femoropopliteal bypass grafts does not affect 5-year patency rates, age and graft size do influence results. These factors should be considered before a prosthetic bypass grafting procedure. Furthermore, these data should serve as a contemporary standard, with which evolving and conventional procedures can be compared.

  13. 111 In-labeled leukocytes in the detection of prosthetic vascular graft infections

    International Nuclear Information System (INIS)

    Williamson, M.R.; Boyd, C.M.; Read, R.C.; Thompson, B.W.; Barnes, R.W.; Shah, H.R.; Balachandran, S.; Ferris, E.J.

    1986-01-01

    Making a clinical diagnosis of infection in prosthetic vascular grafts is difficult but when undiagnosed, this condition has a high mortality rate. Using Indium-111-labeled white-blood cells, 30 scans were performed in 21 patients suspected of having a prosthetic graft infection. The diagnosis of infected graft was confirmed by surgery in all cases, and lack of infection was established by resolution of symptoms with conservative therapy. Twenty-four hour scans of autologous Indium-111 leukocytes were obtained, and correlative CT studies were done in 11 cases. There were 13 infected grafts at surgery (purulent material present), and scans were positive in all (100% sensitivity); of 17 scans, there were 15 true negatives and two false positives (88% specificity). Using the criteria of gas or fluid around the graft, the sensitivity of CT was only 37% in a small subset of these patients. One-half of the cases in which infection was suspected clinically had no infection and had negative scans. Various types of grafts and graft materials were used, and there was no correlation with presence or absence of infection on the basis of the type of graft. Extragraft infection sites were found in five patients. In conclusion, use of Indium-111 leukocytes has been found to be an accurate and valuable diagnostic method for evaluation of suspected prosthetic vascular graft infection, and to have higher diagnostic accuracy than CT

  14. Prosthetic vascular graft infection through a median sternotomy: a multicentre review †.

    Science.gov (United States)

    Oda, Tatsuya; Minatoya, Kenji; Kobayashi, Junjiro; Okita, Yutaka; Akashi, Hidetoshi; Tanaka, Hiroyuki; Kawaharada, Nobuyoshi; Saiki, Yoshikatsu; Kuniyoshi, Yukio; Nishimura, Kunihiro

    2015-06-01

    The aim of this study is to analyse the treatment outcomes of thoracic prosthetic graft infection. A retrospective chart review was conducted at six hospitals and included the records of 68 patients treated for postoperative prosthetic vascular graft infection (mean age: 62.3 ± 15.1, male 51) from January 2000 to December 2013. The number of patients and the locations of the treated infections were as follows: 13 for aortic root, 16 for ascending aorta, 35 for aortic arch and 4 for aortic root to arch. In-hospital infection occurred in 43 patients and after discharge in 25. The mean follow-up time was 2.0 ± 2.3 years. The follow-up rate was 94.1%. The most commonly isolated micro-organism was Staphylococcus aureus (72.1%). Rereplacement of infectious graft was performed in 18 patients (Dacron graft in 12, homograft in 4 and rifampicin-bonded Dacron graft in 2). The overall hospital mortality rate was 35.3% (24/68). The mortality rate among the patients with graft rereplacement was 33.3% (6/18), with pedicled muscle flaps or pedicled omental flaps to cover the graft 25.9% (7/27), with irrigation 55.0% (11/20) and on antibiotic therapy only 0% (0/3). Our multivariate analysis demonstrated that the risk factors of hospital death increased in the absence of pedicled flaps (muscle or omentum) to cover the graft (P = 0.001), age over 55 (P = 0.003), time from onset of initial operation prosthetic vascular graft infection have not been satisfactory. However, the use of pedicled muscle or omental flaps to cover the graft could improve the outcomes. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  15. Conservative treatment of vascular prosthetic graft infection is associated with high mortality

    NARCIS (Netherlands)

    Saleem, Ben R.; Meetwaldt, Robbert; Tielliu, Ignace F. J.; Verhoeven, Eric L. G.; van den Dungen, Jan J. A. M.; Zeebregts, Clark J.

    BACKGROUND: The aim of this study was to identify patient-related and/or disease-related factors that influence outcomes in patients with vascular prosthetic graft infections. METHODS: Through the hospital patient administration system, between January 1997 and December 2007, a total of 44 patients

  16. F-18-Fluorodeoxyglucose Positron Emission Tomography/CT Scanning in Diagnosing Vascular Prosthetic Graft Infection

    NARCIS (Netherlands)

    Saleem, Ben R.; Pol, Robert A.; Slart, Riemer H. J. A.; Reijnen, Michel M. P. J.; Zeebregts, Clark J.

    2014-01-01

    Vascular prosthetic graft infection (VPGI) is a severe complication after vascular surgery. CT-scan is considered the diagnostic tool of choice in advanced VPGI. The incidence of a false-negative result using CT is relatively high, especially in the presence of low-grade infections.

  17. Indium-111 leukocyte localization in infected prosthetic graft

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    Purnell, G.L.; Walker, C.W.; Allison, J.W.; Dalrymple, G.V. (Univ. of Arkansas for Medical Sciences, Little Rock (USA))

    1990-08-01

    Infective endocarditis can be difficult to prove, even in the face of strong clinical suspicion. A case in which standard methods of diagnosis failed to demonstrate endocarditis in a patient with recurrent Staphylococcus aureus bacteremia and porcine aortic valve is reported. An In-111 labelled leukocyte SPECT study demonstrated uptake in the aortic root and leaflets, and autopsy demonstrated vegetations on the leaflets. In-111 may prove useful in demonstrating endocarditis in patients with prosthetic valve infection.

  18. Indium-111 leukocyte localization in infected prosthetic graft

    International Nuclear Information System (INIS)

    Purnell, G.L.; Walker, C.W.; Allison, J.W.; Dalrymple, G.V.

    1990-01-01

    Infective endocarditis can be difficult to prove, even in the face of strong clinical suspicion. A case in which standard methods of diagnosis failed to demonstrate endocarditis in a patient with recurrent Staphylococcus aureus bacteremia and porcine aortic valve is reported. An In-111 labelled leukocyte SPECT study demonstrated uptake in the aortic root and leaflets, and autopsy demonstrated vegetations on the leaflets. In-111 may prove useful in demonstrating endocarditis in patients with prosthetic valve infection

  19. Computerized tomographic evaluation of aortic prosthetic graft complications

    International Nuclear Information System (INIS)

    Kay, D.; Kalmar, J.A.

    1985-01-01

    Computerized tomography has been found to be an accurate and sensitive method of diagnosing complications of synthetic aortic grafts. Complications in this series of four cases included aortoesophageal fistula, aortoduodenal fistula, pseudoaneurysm, and retroperitoneal hematoma. 6 references, 5 figures

  20. 99mTc-leukocyte scintigraphy in prosthetic vascular graft infections

    International Nuclear Information System (INIS)

    Vorne, M.; Laitinen, J.; Lehtonen, J.; Toivio, I.; Mokka, R.; Soini, I.

    1989-01-01

    The aim of this study was to determine the diagnostic value of scintigraphy with 99m Tc-HMPAO-labelled leukocytes for the detection of prosthetic vascular graft infection. 51 scans were recorded in 19 patients with suspected vascular graft infection and 8 control patients. Three-phase scanning was used at 0.5, 3-6 and 18-24 h. 13 vascular graft infections (10 early, 3 late) were found. 12 of these healed with antibiotics and only one patient with late infection had to be reoperated. None of them died during the follow-up period. The sensitivity was 100% and the specificity 96%. 99m Tc-leukocyte scintigraphy seems a useful tool to detect vascular graft infection and to differentiate it from infections elsewhere. The results suggest that the incidence of vascular graft infection may be greater, and the mortality rate lower, than supposed before. (orig.) [de

  1. Multidisciplinary Treatment Approach for Prosthetic Vascular Graft Infection in the Thoracic Aortic Area

    Science.gov (United States)

    Watanabe, Yoshinori

    2015-01-01

    Prosthetic vascular graft infection in the thoracic aortic area is a rare but serious complication. Adequate management of the complication is essential to increase the chance of success of open surgery. While surgical site infection is suggested as the root cause of the complication, it is also related to decreased host tolerance, especially as found in elderly patients. The handling of prosthetic vascular graft infection has been widely discussed to date. This paper mainly provides a summary of literature reports published within the past 5 years to discuss issues related to multidisciplinary treatment approaches, including surgical site infection, timing of onset, diagnostic methods, causative pathogens, auxiliary diagnostic methods, antibiotic treatment, anti-infective structures of vascular prostheses, surgical treatment, treatment strategy against infectious aortic aneurysms, future surgical treatment, postoperative systemic therapy, and antimicrobial stewardship. A thorough understanding of these issues will enable us to prevent prosthetic vascular graft infection in the thoracic aortic area as far as possible. In the event of its occurrence, the early introduction of appropriate treatment is expected to cure the disease without worsening of the underlying pathological condition. PMID:26356686

  2. Cryopreserved Human Allografts for the Reconstruction of Aortic and Peripheral Prosthetic Graft Infection.

    Science.gov (United States)

    Bossi, Matteo; Tozzi, Matteo; Franchin, Marco; Ferraro, Stefania; Rivolta, Nicola; Ferrario, Massimo; Guttadauro, Chiara; Castelli, Patrizio; Piffaretti, Gabriele

    2017-12-25

    Background : This study aimed to present cases with cryopreserved human allografts (CHAs) for vascular reconstruction in both aortic and peripheral infected prosthetic grafts. Materials and Methods : This is a single center, observational descriptive study with retrospective analysis. In all cases, the infected prosthetic graft material was completely removed. At discharge, patients were administered anticoagulants. Follow-up examinations included clinical visits, echo-color-Doppler ultrasounds, or computed tomography angiography within 30 days and at 3, 6, and 12 months after the treatment, and then twice per year. Results : We treated 21 patients (90% men, n=19) with the mean age of 71±12 years and mean interval between the initial operation and replacement with CHA of 30 months [range, 1-216; interquartile range (IQR), 2-36]. In-hospital mortality was 14% (n=3); no CHA-related complication led to death. Limb salvage was 100%. No patient was lost at the median follow-up of 14 months (range, 2-61; IQR, 6-39). No rupture, aneurysmal degeneration, or re-infection occurred. Estimated freedom from CHA-related adverse events (95% confidence interval, 43-63) was 95% at 3 years. Conclusion : In our experience, CHAs are a viable option for prosthetic graft infections and provide satisfactory clinical results and favorable stability because of a very low rate of CHA-related adverse events during follow-up.

  3. Surgical and Antimicrobial Treatment of Prosthetic Vascular Graft Infections at Different Surgical Sites: A Retrospective Study of Treatment Outcomes

    Science.gov (United States)

    Elzi, Luigia; Gurke, Lorenz; Battegay, Manuel; Widmer, Andreas F.; Weisser, Maja

    2014-01-01

    Objective Little is known about optimal management of prosthetic vascular graft infections, which are a rare but serious complication associated with graft implants. The goal of this study was to compare and characterize these infections with respect to the location of the graft and to identify factors associated with outcome. Methods This was a retrospective study over more than a decade at a tertiary care university hospital that has an established multidisciplinary approach to treating graft infections. Cases of possible prosthetic vascular graft infection were identified from the hospital's infectious diseases database and evaluated against strict diagnostic criteria. Patients were divided into groups according to the locations of their grafts: thoracic-aortic, abdominal-aortic, or peripheral-arterial. Statistical analyses included evaluation of patient and infection characteristics, time to treatment failure, and factors associated specifically with cure rates in aortic graft infections. The primary endpoint was cure at one year after diagnosis of the infection. Results Characterization of graft infections according to the graft location did show that these infections differ in terms of their characteristics and that the prognosis for treatment seems to be influenced by the location of the infection. Cure rate and all-cause mortality at one year were 87.5% and 12.5% in 24 patients with thoracic-aortic graft infections, 37.0% and 55.6% in 27 patients with abdominal-aortic graft infections, and 70.0% and 30.0% in 10 patients with peripheral-arterial graft infections. In uni- and multivariate analysis, the type of surgical intervention used in managing infections (graft retention versus graft replacement) did not affect primary outcome, whereas a rifampicin-based antimicrobial regimen was associated with a higher cure rate. Conclusions We recommend that future prospective studies differentiate prosthetic vascular graft infections according to the location of the

  4. Indium-111 platelet imaging for detection of platelet deposition in abdominal aneurysms and prosthetic arterial grafts

    International Nuclear Information System (INIS)

    Ritchie, J.L.; Stratton, J.R.; Thiele, B.; Haminton, G.W.; Warrick, L.N.; Huang, T.W.; Harker, L.A.

    1981-01-01

    Thirty-four platelet imaging studies were performed in 23 patients to determine whether platelet deposition could be detected in patients with vascular aneurysms (18 patients) or in patients in whom Dacron prosthetic grafts had been placed (5 patients). In patients in whom abnormal platelet deposition was detected, the effect of administration of platelet-active drugs on platelet deposition was examined. Of the 18 patients with an aneurysm, 12 had equivocally positive studies on initial imaging and 2 had equivocally positive images. Of five patients with Dacron arterial grafts in place, four had diffuse platelet deposition in the grafts; the fifth patient had a platelet deposition only in a pseudoaneurysm. Eight patients with an abdominal aneurysm and positive or equivocally positive baseline images were restudied during platelet-active drug therapy either with aspirin plus dipyridamole (seven patients) or with sulfinpyrazone (four patients). No patient studied during treatment with aspirin plus dipyridamole had detectably decreased platelet deposition compared with baseline determinations. In contrast, two of four patients studied while receiving sulfinpyrazone showed decreased platelet deposition. Thus, platelet imaging may be of value for studying platelet physiology in vivo and for assessing platelet-active drugs and the thrombogenicity of prosthetic graft materials in human beings

  5. Brief report: biomarkers of aortic vascular prosthetic graft infection in a porcine model with Staphylococcus aureus

    DEFF Research Database (Denmark)

    Langerhuus, S. N.; Tønnesen, E. K.; Jensen, K. H.

    2010-01-01

    Aortic vascular prosthetic graft infection (AVPGI) with Staphylococcus aureus is a feared post-operative complication. This study was conducted to evaluate the clinical signs and potential biomarkers of infection in a porcine AVPGI model. The biomarkers evaluated were: C-reactive protein (CRP......), fibrinogen, white blood cells (WBC), major histocompatibility complex II (MHC II) density, lymphocyte CD4:CD8 ratio and tumour necrosis factor-alpha (TNF-α) in vitro responsiveness. Sixteen pigs were included in the study, and randomly assigned into four groups (n = 4): “SHAM” pigs had their infra...

  6. Visualization of a prosthetic vascular graft due to platelet contamination during 111Indium-labeled leukocyte scintigraphy

    International Nuclear Information System (INIS)

    Oates, E.; Ramberg, K.

    1988-01-01

    A prosthetic axillo-femoral bypass graft was visualized during 111 In-labeled leukocyte scintigraphy in a patient referred for possible abdominal abscess. The presence of significant cardiac blood-pool activity raised the possibility that this uptake was due to deposition of contaminating labeled platelets rather than labeled leukocytes. An analysis of a small sample of the patient's blood confirmed that the circulating activity was due to labeled platelets. Increased activity along prosthetic vascular grafts in patients undergoing 111 In-labeled leukocyte scintigraphy may be due to adherent platelet, and not indicative of infection

  7. Effects of cilostazol and k-134 on reconstructive surgery using prosthetic grafts in the abdominal aorta of beagle dogs.

    Science.gov (United States)

    Inoue, Yoshinori; Sugano, Norihide; Jibiki, Masatoshi; Kudo, Toshifumi; Iwai, Takehisa

    2008-01-01

    Problems associated with prosthetic graft replacement are stenosis at the anastomosis site and thrombus formation on the inner surface. Cilostazol is known to have antiplatelet activity and inhibit vascular smooth muscle cell proliferation and neointima thickening. A cilostazol derivative, (-)-6-[3-[3-cyclopropyl-3-[(1R,2R)-2-hydroxycyclohexyl]ureido]-propoxy]-2-(1H)-quinolinone (K-134), has more potent anti-platelet activity and anti-neointimal thickening activity than cilostazol in the in-vitro platelet aggregation and in-vivo anti-hyperplastic activity assay. The aim of this study was to investigate effects of cilostazol and K-134 on thrombus formation and neointimal thickening at the site of prosthetic graft replacement. Beagle dogs underwent infrarenal abdominal aortic resection with straight Dacron graft replacement, which were allocated to the control, cilostazol, and K-134 groups. Two dogs were dead without confirming the cause of death. After 6 months, all dogs were necropsied. All prosthetic grafts were patent in each group. Ratios of red thrombus to prosthetic graft area were 0.3+/-6.4%, and 3.3+/-4.5% in the cilostazol and K-134 groups, respectively, which were significant different from that in the control group (24.4+/-16.8%). However, no clear difference was seen among the 3 groups with respect to neointimal thickness (control group, 0.70+/-0.13 mm; cilostazol group, 0.59+/-0.14 mm; K-134 group, 0.67+/-0.14 mm). Cilostazol and K-134 significantly inhibited thrombus formation on the inner surface of the prosthetic graft at 6 months after graft replacement. Neointimal thickening on the inner surface was slight even in control-group animals, and the effects of cilostazol and K-134 on such thickening were unclear.

  8. Accuracy of FDG-PET-CT in the Diagnostic Work-up of Vascular Prosthetic Graft Infection

    NARCIS (Netherlands)

    Bruggink, J. L. M.; Glaudemans, A. W. J. M.; Saleem, B. R.; Meerwaldt, R.; Alkefaji, H.; Prins, T. R.; Start, R. H. J. A.; Zeebregts, C. J.

    Objectives: To investigate the diagnostic accuracy of fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) compared with computed tomography (CT) scanning and added value of fused FDG-PET CT in diagnosing vascular prosthetic graft infection. Design: Prospective cohort study with

  9. Detection of thoracic aortic prosthetic graft infection with 18F-fluorodeoxyglucose positron emission tomography/computed tomography.

    Science.gov (United States)

    Tokuda, Yoshiyuki; Oshima, Hideki; Araki, Yoshimori; Narita, Yuji; Mutsuga, Masato; Kato, Katsuhiko; Usui, Akihiko

    2013-06-01

    To investigate the diagnostic value of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in detecting thoracic aortic prosthetic graft infection. Nine patients with clinically suspected thoracic aortic graft infection underwent FDG-PET/CT scanning. In these patients, the diagnoses could not be confirmed using conventional modalities. The patients' clinical courses were retrospectively reviewed. On the basis of surgical, microbiological and clinical follow-up findings, the aortic grafts were considered infected in 4 patients and not infected in 5. All 4 patients with graft infection (root: 2 cases, arch: 1 case and descending: 1 case) eventually underwent in situ re-replacement. Two of the 4 patients also had abdominal grafts; however, only the thoracic grafts were replaced because uptake was low around the abdominal grafts. The maximal standardized uptake value (SUVmax) in the perigraft area was higher in the infected group than in the non-infected group (11.4 ± 4.5 vs 6.9 ± 6.4), although the difference was not statistically significant. According to the receiver operating characteristic analysis, SUVmax >8 appeared to be the cut-off value in distinguishing the two groups (sensitivity: 1.0 and specificity: 0.8). FDG-PET/CT is useful for confirming the presence of graft infection by detecting high uptake around grafts and excluding other causes of inflammation. An SUVmax value greater than 8 around a graft suggests the presence of graft infection. In addition, FDG-PET/CT can be used to clarify the precise extent of infection. This is especially useful if multiple separated prosthetic grafts have been implanted.

  10. Effects of sterilization and storage on the properties of ALP-grafted biomaterials for prosthetic and bone tissue engineering applications

    International Nuclear Information System (INIS)

    Ferraris, S; Pan, G; Vernè, E; Spriano, S; Cassinelli, C; Mazzucco, L

    2012-01-01

    Grafting of the biomaterial surfaces with biomolecules is nowadays a challenging research field for prosthetic and bone tissue engineering applications. On the other hand, very few research works investigate the effect of the sterilization processes on the properties of functionalized biomaterials. In this study, the effects of different sterilization techniques (e.g. gamma and electron beam irradiation, ethylene oxide) on the enzymatic activity of bioactive glasses and Ti6Al4V grafted with alkaline phosphatase (ALP) have been analyzed. Sterility maintenance and in vitro bioactivity of the sterilized surfaces have also been investigated. Finally the effect of packaging and storage conditions has been considered. (paper)

  11. Sustained release of vancomycin from novel biodegradable nanofiber-loaded vascular prosthetic grafts: in vitro and in vivo study

    OpenAIRE

    Liu, Kuo-Sheng; Lee, Cheng-Hung; Wang, Yi-Chuan; Liu, Shih-Jung

    2015-01-01

    Kuo-Sheng Liu,1 Cheng-Hung Lee,2 Yi-Chuan Wang,3 Shih-Jung Liu3 1Department of Thoracic and Cardiovascular Surgery, Chang Gung Memorial Hospital, Linkou, Taiwan; 2Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan; 3Department of Mechanical Engineering, Chang Gung University, Tao-Yuan, Taiwan Abstract: This study describes novel biodegradable, drug-eluting nanofiber-loaded vascular prosthetic grafts that provide local and sustained...

  12. 18F-Fluorodeoxyglucose Positron Emission Tomography/CT Scanning in Diagnosing Vascular Prosthetic Graft Infection

    Science.gov (United States)

    Saleem, Ben R.; Pol, Robert A.; Slart, Riemer H. J. A.; Reijnen, Michel M. P. J.; Zeebregts, Clark J.

    2014-01-01

    Vascular prosthetic graft infection (VPGI) is a severe complication after vascular surgery. CT-scan is considered the diagnostic tool of choice in advanced VPGI. The incidence of a false-negative result using CT is relatively high, especially in the presence of low-grade infections. 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) scanning has been suggested as an alternative for the diagnosis and assessment of infectious processes. Hybrid 18F-FDG PET/CT has established the role of 18F-FDG PET for the assessment of suspected VPGI, providing accurate anatomic localization of the site of infection. However, there are no clear guidelines for the interpretation of the uptake patterns of 18F-FDG as clinical tool for VPGI. Based on the available literature it is suggested that a linear, diffuse, and homogeneous uptake should not be regarded as an infection whereas focal or heterogeneous uptake with a projection over the vessel on CT is highly suggestive of infection. Nevertheless, 18F-FDG PET and 18F-FDG PET/CT can play an important role in the detection of VPGI and monitoring response to treatment. However an accurate uptake and pattern recognition is warranted and cut-off uptake values and patterns need to be standardized before considering the technique to be the new standard. PMID:25210712

  13. Vascularized nerve grafts: an experimental study.

    Science.gov (United States)

    Donzelli, Renato; Capone, Crescenzo; Sgulò, Francesco Giovanni; Mariniello, Giuseppe; Maiuri, Francesco

    2016-08-01

    The aim of this study is to define an experimental model in order to promote the functional recovery of the nerves using grafts with vascular support (Vascular Nerve Grafts - VNG). The aim of this study is to define, on an experimental model in normal recipient bed, whether the functional recovery with VNG is superior to that obtained non-vascularized graft (NNG). Twenty male rabbits, which underwent dissection of sciatic nerve, were later treated by reinnervation through an autograft. In 10 animals the reconstruction of sciatic nerve was realized with VNG; in 10 control animals the reconstruction of sciatic nerve was realized with NNG. The VNG group showed a better axonal organization and a significantly higher number of regenerated axons in the early phases (after 30 days) than the NNG group, whereas the difference in the axonal number at day 90 was less significant; besides, the axon diameter and the myelin thickness were not significantly improved by VNG group. Our data suggests that the use of VNG leads to a faster regeneration process and a better functional recovery, although the final results are comparable to those of the NNG. VNG improve the quality of the axonal regeneration (axonal diameter and Schwann cells), although the increase in the axonal number is not significant and does not improve the long-term functional outcome.

  14. Experimental measurement of flexion-extension movement in normal and corpse prosthetic elbow joint.

    Science.gov (United States)

    TarniŢă, Daniela; TarniŢă, DănuŢ Nicolae

    2016-01-01

    This paper presents a comparative experimental study of flexion-extension movement in healthy elbow and in the prosthetic elbow joint fixed on an original experimental bench. Measurements were carried out in order to validate the functional morphology and a new elbow prosthesis type ball head. The three-dimensional (3D) model and the physical prototype of our experimental bench used to test elbow endoprosthesis at flexion-extension and pronation-supination movements is presented. The measurements were carried out on a group of nine healthy subjects and on the prosthetic corpse elbow, the experimental data being obtained for flexion-extension movement cycles. Experimental data for the two different flexion-extension tests for the nine subjects and for the corpse prosthetic elbow were acquired using SimiMotion video system. Experimental data were processed statistically. The corresponding graphs were obtained for all subjects in the experimental group, and for corpse prosthetic elbow for both flexion-extension tests. The statistical analysis has proved that the flexion angles of healthy elbows were significantly close to the values measured at the prosthetic elbow fixed on the experimental bench. The studied elbow prosthesis manages to re-establish the mobility for the elbow joint as close to the normal one.

  15. Coil embolization of a false aneurysm with aorto-cutaneous fistula after prosthetic graft replacement of the ascending aorta

    International Nuclear Information System (INIS)

    Miguel, Bruno; Camilleri, Lionel; Gabrillargues, Jean; Macheda, Bruno; Kubota, Hiroshi; Ravel, Anne; Riberolles, Charles de; Boyer, Louis

    2000-01-01

    Aim: To report palliative embolization of a false aneurysm over the distal suture line of an ascending aorta graft replacement. Material and Method: A 78-year-old male patient was admitted for increasing bleeding of a chronic Manubrium ulceration, 20 months after coronary artery bypass complicated by perioperative ascending aorta dissection requiring prosthetic graft replacement. One month later, he underwent epiploplasty for a mediastinitis followed by long-term antibiotic therapy. Five months later, he presented with a Manubrium ulceration of the sternotomy. Spiral computerized tomography (CT) and aortography revealed a 20 mm anterior peri-prosthetic false aneurysm with a wide neck. Advanced age, active mediastinitis and patient's objection led us to perform percutaneous occlusion according to the Moret remodeling technique while protecting the coils release with balloon catheter inflation. Results: No post-operative complication was observed and at 1-year follow-up the patient was doing well with no recurrent bleeding. Magnetic resonance imaging (MRI) and spiral CT controls confirmed coils stability without any internal flow. Conclusion: Percutaneous coils embolization of a large false aneurysm in the ascending aorta can be a palliative treatment in a surgically unsuited patient

  16. Healthcare-associated prosthetic heart valve, aortic vascular graft, and disseminated Mycobacterium chimaera infections subsequent to open heart surgery.

    Science.gov (United States)

    Kohler, Philipp; Kuster, Stefan P; Bloemberg, Guido; Schulthess, Bettina; Frank, Michelle; Tanner, Felix C; Rössle, Matthias; Böni, Christian; Falk, Volkmar; Wilhelm, Markus J; Sommerstein, Rami; Achermann, Yvonne; Ten Oever, Jaap; Debast, Sylvia B; Wolfhagen, Maurice J H M; Brandon Bravo Bruinsma, George J; Vos, Margreet C; Bogers, Ad; Serr, Annerose; Beyersdorf, Friedhelm; Sax, Hugo; Böttger, Erik C; Weber, Rainer; van Ingen, Jakko; Wagner, Dirk; Hasse, Barbara

    2015-10-21

    We identified 10 patients with disseminated Mycobacterium chimaera infections subsequent to open-heart surgery at three European Hospitals. Infections originated from the heater-cooler unit of the heart-lung machine. Here we describe clinical aspects and treatment course of this novel clinical entity. Interdisciplinary care and follow-up of all patients was documented by the study team. Patients' characteristics, clinical manifestations, microbiological findings, and therapeutic measures including surgical reinterventions were reviewed and treatment outcomes are described. The 10 patients comprise a 1-year-old child and nine adults with a median age of 61 years (range 36-76 years). The median duration from cardiac surgery to diagnosis was 21 (range 5-40) months. All patients had prosthetic material-associated infections with either prosthetic valve endocarditis, aortic graft infection, myocarditis, or infection of the prosthetic material following banding of the pulmonary artery. Extracardiac manifestations preceded cardiovascular disease in some cases. Despite targeted antimicrobial therapy, M. chimaera infection required cardiosurgical reinterventions in eight patients. Six out of 10 patients experienced breakthrough infections, of which four were fatal. Three patients are in a post-treatment monitoring period. Healthcare-associated infections due to M. chimaera occurred in patients subsequent to cardiac surgery with extracorporeal circulation and implantation of prosthetic material. Infections became clinically apparent after a time lag of months to years. Mycobacterium chimaera infections are easily missed by routine bacterial diagnostics and outcome is poor despite long-term antimycobacterial therapy, probably because biofilm formation hinders eradication of pathogens. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  17. Risk factors and outcomes for nosocomial infection after prosthetic vascular grafts.

    Science.gov (United States)

    Fariñas, María Carmen; Campo, Ana; Duran, Raquel; Sarralde, José Aurelio; Nistal, Juan Francisco; Gutiérrez-Díez, José Francisco; Fariñas-Álvarez, Concepción

    2017-11-01

    The objective of this study was to determine risk factors for nosocomial infections (NIs) and predictors of mortality in patients with prosthetic vascular grafts (PVGs). This was a prospective cohort study of all consecutive patients who underwent PVG of the abdominal aorta with or without iliac-femoral involvement and peripheral PVG from April 2008 to August 2009 at a university hospital. Patients younger than 15 years and those with severe immunodeficiency were excluded. The follow-up period was until 3 years after surgery or until death. There were 261 patients included; 230 (88.12%) were male, and the mean age was 67.57 (standard deviation, 10.82) years. The reason for operation was aortic aneurysm in 49 (18.77%) patients or lower limb arteriopathy in 212 (81.23%) patients. NIs occurred in 71 (27.20%) patients. Of these, 42 were surgical site infections (SSIs), of which 61.9% occurred in the lower extremities (14 superficial, 10 deep, and 2 PVG infections) and 38.1% in the abdomen (7 superficial, 7 deep, and 2 PVG infections); 15 were respiratory tract infections; and 15 were urinary tract infections. Active lower extremity skin and soft tissue infection (SSTI) at the time of surgery was a significant predictor of NI for both types of PVG (abdominal aortic PVG: adjusted odds ratio [OR], 12.6; 95% confidence interval [CI], 1.15-138.19; peripheral PVG: adjusted OR, 2.43; 95% CI, 1.08-5.47). Other independent predictors of NI were mechanical ventilation (adjusted OR, 55.96; 95% CI, 3.9-802.39) for abdominal aortic PVG and low hemoglobin levels on admission (adjusted OR, 0.84; 95% CI, 0.71-0.99) and emergent surgery (adjusted OR, 4.39; 95% CI, 1.51-12.74) for peripheral PVG. The in-hospital mortality rate was 1.92%. The probability of surviving the first month was 0.96, and significant predictors of mortality were active lower extremity SSTI (adjusted risk ratio [RR], 12.07; 95% CI, 1.04-154.75), high postsurgical glucose levels (adjusted RR, 1.02; 95% CI, 1

  18. [An experimental study of the healing of velour grafts].

    Science.gov (United States)

    Kobayashi, O

    1986-02-01

    An experimental study of implantation of velour grafts in the abdominal aorta or the external iliac artery of dogs was conducted with the object of evaluating the type of velour surface best fit for small-caliber artery implantation. Velour grafts measuring 4mm in diameter with differing velour surfaces were used as materials. Velour grafts now available on the market differ not only in velour surface but also in structure, notably in porosity and wall thickness. Hence each of the grafts used was reversed (i.e. inside out) and thus new grafts were prepared. These grafts were considered most suitable for making a comparative study of the effects of velour surface on healing. Macroscopic and histological findings revealed that each graft was good healing with the rate of patency as high as 84 percent. However, like Vasculour-D grafts, crimped grafts which preserve the crimp after implantation was significantly thicker at the internal valley than other grafts. Based on the findings of this experimental study non-crimped velour grafts were considered to be best fit for small-caliber artery implantation.

  19. Less Than Total Excision of Infected Prosthetic PTFE Graft Does Not Increase the Risk of Reinfection.

    Science.gov (United States)

    Sgroi, Michael D; Kirkpatrick, Vincent E; Resnick, Karen A; Williams, Russell A; Wilson, Samuel E; Gordon, Ian L

    2015-01-01

    Traditional treatment of infected polytetrafluoroethylene (PTFE) grafts consist of removal of the entire prosthesis. Closure of the native vessels may compromise vascular patency. We examined the outcomes for patients in whom a PTFE remnant of an infected graft was retained on the vessel. We reviewed the operating room log from 2000 to 2011 and identified all patients who had partial removal of an infected PTFE graft used for hemodialysis or peripheral bypass. These patients were examined for subsequent complications. Twenty-seven patients underwent 30 partial graft excisions with mean follow-up of 27 months. A total of 17% (5 of 30) of the partial graft resection procedures resulted in complications. Of 48 total remnants left behind at the arterial or venous anastomoses, reinfection occurred in 15%. Leaving a well-incorporated small 1-to 5-mm PTFE remnant at the arterial or venous anastomoses can be performed safely with a low risk of complications. © The Author(s) 2015.

  20. A Case Report of Ridge Augmentation using Onlay Interpositional Graft: An Approach to Improve Prosthetic Prognosis of a Deficit Ridge

    Directory of Open Access Journals (Sweden)

    Devanand Shetty

    2014-01-01

    Full Text Available Background: Periodontal therapy has developed beyond the scope of the treatment of periodontal pathoses. Periodontal plastic surgery consists of the reconstructive procedures designed to enhance the both function and esthetics. Deficient ridges pose a severe problem to the restorative dentist in restoring the natural form, function and esthetics of the prosthesis replacing the natural dentition. Depending upon the severity, location of these defects and the prosthetic option chosen, hard and soft tissue ridge augmentation or non-surgical approach or a combination may help to address them. The present clinical report describes a soft tissue ridge augmentation of a localized ridge defect in maxillary aesthetic region using onlay interpositional graft followed by fixed partial denture.

  1. Late prosthetic graft infection after frozen elephant trunk presenting by haemoptysis and positive ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography.

    Science.gov (United States)

    Morjan, Mohammed; Ali, Khaldoun; Harringer, Wolfgang; El-Essawi, Aschraf

    2014-11-01

    In cardiothoracic surgery, prosthetic graft infection represents a diagnostic and therapeutic challenge. Although clinical assessment, imaging techniques and microbiological investigations are helpful, late graft infection can be difficult to identify using classical diagnostic tools. An aggressive surgical approach involving removal and replacement of all prosthetic materials is technically demanding but remains the best strategy to eradicate infection. Herein, we report a case of a late aortic graft infection, after frozen elephant trunk implantation with atypical presentation, diagnosed with (18)F-fluorodeoxyglucose-positron emission tomography and treated successfully through a radical surgical strategy. This case emphasizes the emerging diagnostic role of positron emission tomography and encourages the adoption of an aggressive surgical approach. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  2. Outcomes of Prosthetic Hemodialysis Grafts after Deployment of Bare Metal versus Covered Stents at the Venous Anastomosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Charles Y., E-mail: charles.kim@duke.edu; Tandberg, Daniel J.; Rosenberg, Michael D.; Miller, Michael J.; Suhocki, Paul V.; Smith, Tony P. [Duke University Medical Center, Division of Vascular and Interventional Radiology (United States)

    2012-08-15

    Purpose: To compare postintervention patency rates after deployment of bare metal versus covered stents across the venous anastomosis of prosthetic arteriovenous (AV) grafts. Methods: Review of our procedural database over a 6 year period revealed 377 procedures involving stent deployment in an AV access circuit. After applying strict inclusion criteria, our study group consisted of 61 stent deployments in 58 patients (median age 58 years, 25 men, 33 women) across the venous anastomosis of an upper extremity AV graft circuit that had never been previously stented. Both patent and thrombosed AV access circuits were retrospectively analyzed. Within the bare metal stent group, 20 of 32 AV grafts were thrombosed at initial presentation compared to 18 of 29 AV grafts in the covered stent group. Results: Thirty-two bare metal stents and 29 covered stents were deployed across the venous anastomosis. The 3, 6, and 12 months primary access patency rates for bare metal stents were not significantly different than for covered stents: 50, 41, and 22 % compared to 59, 52, and 29 %, respectively (p = 0.21). The secondary patency rates were also not significantly different: 78, 78, and 68 % for bare metal stents compared to 76, 69, and 61 % for covered stents, respectively (p = 0.85). However, covered stents demonstrated a higher primary stent patency rate than bare metal stents: 100, 85, and 70 % compared to 75, 67, and 49 % at 3, 6, and 12 months (p < 0.01). Conclusion: The primary and secondary access patency rates after deployment of bare metal versus covered stents at the venous anastomosis were not significantly different. However, bare metal stents developed in-stent stenoses significantly sooner.

  3. Outcomes of Prosthetic Hemodialysis Grafts after Deployment of Bare Metal versus Covered Stents at the Venous Anastomosis

    International Nuclear Information System (INIS)

    Kim, Charles Y.; Tandberg, Daniel J.; Rosenberg, Michael D.; Miller, Michael J.; Suhocki, Paul V.; Smith, Tony P.

    2012-01-01

    Purpose: To compare postintervention patency rates after deployment of bare metal versus covered stents across the venous anastomosis of prosthetic arteriovenous (AV) grafts. Methods: Review of our procedural database over a 6 year period revealed 377 procedures involving stent deployment in an AV access circuit. After applying strict inclusion criteria, our study group consisted of 61 stent deployments in 58 patients (median age 58 years, 25 men, 33 women) across the venous anastomosis of an upper extremity AV graft circuit that had never been previously stented. Both patent and thrombosed AV access circuits were retrospectively analyzed. Within the bare metal stent group, 20 of 32 AV grafts were thrombosed at initial presentation compared to 18 of 29 AV grafts in the covered stent group. Results: Thirty-two bare metal stents and 29 covered stents were deployed across the venous anastomosis. The 3, 6, and 12 months primary access patency rates for bare metal stents were not significantly different than for covered stents: 50, 41, and 22 % compared to 59, 52, and 29 %, respectively (p = 0.21). The secondary patency rates were also not significantly different: 78, 78, and 68 % for bare metal stents compared to 76, 69, and 61 % for covered stents, respectively (p = 0.85). However, covered stents demonstrated a higher primary stent patency rate than bare metal stents: 100, 85, and 70 % compared to 75, 67, and 49 % at 3, 6, and 12 months (p < 0.01). Conclusion: The primary and secondary access patency rates after deployment of bare metal versus covered stents at the venous anastomosis were not significantly different. However, bare metal stents developed in-stent stenoses significantly sooner.

  4. Efficacy of a novel strategy for poststernotomy deep sternal infection after thoracic aorta replacement using a prosthetic graft.

    Science.gov (United States)

    Kuriyama, Motone; Yoshida, Yukitaka; Ninomiya, Hitoshi; Yamamoto, Shin; Sasaguri, Shiro; Akita, Shinsuke; Mitsukawa, Nobuyuki

    2018-05-01

    Poststernotomy deep sternal wound infections are persistent and occasionally fatal, especially in cases involving prosthetic grafts, because of their complicated structure and virtual impossibility of removal. We aimed to verify the influence of cooperation with plastic surgeons and our novel strategy for treating deep sternal wound infection after aortic replacement on cardiovascular surgery outcomes. Nine hundred eighty-three consecutive patients were divided into two groups: an early group (2012-2013) and a late group (2014-2015). The late group had received cooperatively improved perioperative wound management: our novel strategy of deep sternal infection based on radical debridement and immediate reconstruction decided by reference to severities of the patient's general condition and widespread infection by early intervention of plastic surgeons. The groups were analysed retrospectively. Binary variables were analysed statistically with the Fisher exact test and continuous variables with the Mann-Whitney U test. Inter-group differences were assessed with the chi-square test. Twenty of 390 cases in the early group and 13 of 593 cases in the late group were associated with deep sternal infection. Morbidity rates of deep sternal wound infection and associated mortality rates 1 year after reconstruction surgery were significantly less (p infection also reduced associated mortality rates. Facilities should consider the early inclusion of plastic surgeons in the treatment of patients undergoing aortic replacement to facilitate better outcomes. Copyright © 2018 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  5. Corynebacterium minutissimum vascular graft infection: case report and review of 281 cases of prosthetic device-related Corynebacterium infection.

    Science.gov (United States)

    Reece, Rebecca M; Cunha, Cheston B; Rich, Josiah D

    2014-09-01

    Corynebacterium spp. have proven their pathogenic potential in causing infections, particularly in the setting of immunosuppression and prosthetic devices. We conducted a PubMed literature review of all cases of Corynebacterium prosthetic device infections published in the English language through December 2013. The majority of cases involved peritoneal dialysis and central venous catheters, but prosthetic joints and central nervous system shunts/drains were also involved. The management of these cases in terms of retention or removal of the device was not uniform; however, the overall mortality remained the same among both groups. All of these prosthetic device infections pose potential problems in management when the device cannot be removed safely for the patient, especially with the lack of data on the pathogenicity of Corynebacterium species. However with better identification of species and sensitivities, successful treatment is possible even with retention of the device.

  6. Sarpogrelate hydrochloride reduced intimal hyperplasia in experimental rabbit vein graft.

    Science.gov (United States)

    Kodama, Akio; Komori, Kimihiro; Hattori, Keisuke; Yamanouchi, Dai; Kajikuri, Junko; Itoh, Takeo

    2009-05-01

    The selective 5-HT(2A) receptor antagonist sarpogrelate has been clinically used for treatment in atherosclerotic diseases. However, it remains unknown whether administration of sarpogrelate inhibits intimal hyperplasia seen in autologous vein grafts. Therefore, we sought to clarify this question using an experimental rabbit vein graft model. Male rabbits were divided into two groups: a control group and a sarpogrelate-treated group. The jugular vein was interposed in the carotid artery in reversed fashion for 4 weeks and intimal hyperplasia of the grafted vein was measured (n = 8, in each group). Acetylcholine (ACh)-induced endothelium-dependent relaxation was tested by precontraction with prostaglandin F(2alpha) (PGF(2alpha), 5 muM) (n = 5, in each). endothelial nitric oxide synthase (eNOS) protein expression and superoxide production of these veins were also assessed. The suppression of intimal hyperplasia was significantly greater in the sarpogrelate-treated group than in the control group. ACh induced an endothelium-dependent relaxation in the sarpogrelate-treated group (but not in the control group). In endothelium-intact strips from the sarpogrelate-treated group, the nitric oxide (NO) synthase inhibitor nitroarginine enhanced the PGF(2alpha)-induced contraction and blocked the ACh-induced relaxation. Immunoreactive eNOS protein expression was similar between the two groups but superoxide production (estimated from ethidium fluorescence) in endothelial cells was significantly smaller in the sarpogrelate-treated group. The present results indicate that in vivo blockade of 5-HT(2A) receptors leads to an inhibition of intimal hyperplasia in rabbit vein graft. It is suggested that an increased function of endothelium-derived NO through a reduction in endothelial superoxide production may be a possible underlying mechanism for this. These novel findings support the clinical usefulness of sarpogrelate for preventing intimal hyperplasia in vein graft after bypass

  7. Efficacy of linezolid, teicoplanin, and vancomycin in prevention of an experimental polytetrafluoroethylene graft infection model caused by methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Mese, Bulent; Bozoglan, Orhan; Elveren, Serdal; Eroglu, Erdinc; Gul, Mustafa; Celik, Ahmet; Ciralik, Harun; Yildirimdemir, Halil Ibrahim; Yasim, Alptekin

    2015-03-27

    The aim of this study was to evaluate the effectiveness of linezolid, teicoplanin, and vancomycin in prevention of prosthetic vascular graft infections in a vascular graft infection model. Fifty rats were divided into 5 groups. A polytetrafluoroethylene graft was implanted on the back of each rat. Methicillin-resistant Staphylococcus aureus (MRSA) strain was inoculated into all rats except Group 1. Group 2 was not given any treatment, Group 3 received linezolid, Group 4 received vancomycin, and Group 5 received teicoplanin. The grafts were removed for microbiological and histological examinations on the 7th day. In addition, C-reactive protein and prealbumin levels and leukocyte counts in obtained blood specimens were determined. Group 1 did not have infection. Group 2 had bacteria 5.7 × 10(4) CFU/cm(2). Group 3 and Group 4 had less bacterial growth. Group 5 had no bacterial growth. The number of bacteria was significantly higher in Group 2 than in the other experimental groups and the control group (pprevention of prosthetic vascular graft infections.

  8. Amniotic membranes as prosthetic material: experimental utilization data of a rat model.

    Science.gov (United States)

    Zachariou, Z

    1997-10-01

    Prosthetic materials are applied for closing big tissue defects, the repair of traumatized organs, or hernias. Because nonabsorbable synthetic materials are rigid, possess a defined and unchangeable size, and foreign body reaction (FBR) may occur, biological materials may be an alternative. In experimental studies in rats the authors implanted the fetal parts of the human amniotic membranes and examined the utilization and FBR induced in a standardized model. In addition amnion (AM) was combined with vicryl-net (VN) for higher implant stability. Fifteen, 30 and 90 days after implantation, macroscopic appearance was examined, and light microscopy and immunohistology testing of the specimens were performed. Adhesions to parenchymal organs and omentum were present irrespective of the side facing the abdominal cavity. AM induced a rapid FBR, which diminished with time. Chorion (CH) and parts of the AM were resorbed within the examined period after infiltration with recipient cells and neovascularisation. The combined implant, AM, and VN showed best results because disadvantages of one material could be compensated for by the advantages of the other. The studies show that AM, in its anatomic definition, combined with VN proves to be a safe and reliable prosthetic material for the use in tissue defects.

  9. Evaluation of a musculoskeletal model with prosthetic knee through six experimental gait trials.

    Science.gov (United States)

    Kia, Mohammad; Stylianou, Antonis P; Guess, Trent M

    2014-03-01

    Knowledge of the forces acting on musculoskeletal joint tissues during movement benefits tissue engineering, artificial joint replacement, and our understanding of ligament and cartilage injury. Computational models can be used to predict these internal forces, but musculoskeletal models that simultaneously calculate muscle force and the resulting loading on joint structures are rare. This study used publicly available gait, skeletal geometry, and instrumented prosthetic knee loading data [1] to evaluate muscle driven forward dynamics simulations of walking. Inputs to the simulation were measured kinematics and outputs included muscle, ground reaction, ligament, and joint contact forces. A full body musculoskeletal model with subject specific lower extremity geometries was developed in the multibody framework. A compliant contact was defined between the prosthetic femoral component and tibia insert geometries. Ligament structures were modeled with a nonlinear force-strain relationship. The model included 45 muscles on the right lower leg. During forward dynamics simulations a feedback control scheme calculated muscle forces using the error signal between the current muscle lengths and the lengths recorded during inverse kinematics simulations. Predicted tibio-femoral contact force, ground reaction forces, and muscle forces were compared to experimental measurements for six different gait trials using three different gait types (normal, trunk sway, and medial thrust). The mean average deviation (MAD) and root mean square deviation (RMSD) over one gait cycle are reported. The muscle driven forward dynamics simulations were computationally efficient and consistently reproduced the inverse kinematics motion. The forward simulations also predicted total knee contact forces (166Nphysiological motor control patterns during gait. Consequently, the simulations did not accurately predict medial/lateral tibio-femoral force distribution and muscle activation timing. Copyright

  10. Experimental evaluation of new chitin-chitosan graft for duraplasty.

    Science.gov (United States)

    Pogorielov, M; Kravtsova, A; Reilly, G C; Deineka, V; Tetteh, G; Kalinkevich, O; Pogorielova, O; Moskalenko, R; Tkach, G

    2017-02-01

    Natural materials such as collagen and alginate have promising applications as dural graft substitutes. These materials are able to restore the dural defect and create optimal conditions for the development of connective tissue at the site of injury. A promising material for biomedical applications is chitosan-a linear polysaccharide obtained by the deacetylation of chitin. It has been found to be nontoxic, biodegradable, biofunctional and biocompatible in addition to having antimicrobial characteristics. In this study we designed new chitin-chitosan substitutes for dura mater closure and evaluated their effectiveness and safety. Chitosan films were produced from 3 % of chitosan (molar mass-200, 500 or 700 kDa, deacetylation rate 80-90%) with addition of 20% of chitin. Antimicrobial effictively and cell viability were analysed for the different molar masses of chitosan. The film containing chitosan of molar mass 200 kDa, had the best antimicrobial and biological activity and was successfully used for experimental duraplasty in an in vivo model. In conclusion the chitin-chitosan membrane designed here met the requirements for a dura matter graft exhibiting the ability to support cell growth, inhibit microbial growth and biodegradade at an appropriate rate. Therefore this is a promising material for clinical duroplasty.

  11. Textural features of 18F-fluorodeoxyglucose positron emission tomography scanning in diagnosing aortic prosthetic graft infection

    NARCIS (Netherlands)

    Saleem, Ben R.; Beukinga, Roelof J.; Boellaard, Ronald; Glaudemans, Andor W.J.M.; Reijnen, Michel M.P.J.; Zeebregts, Clark J.; Slart, Riemer H.J.A.

    2017-01-01

    Background: The clinical problem in suspected aortoiliac graft infection (AGI) is to obtain proof of infection. Although 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography scanning (PET) has been suggested to play a pivotal role, an evidence-based interpretation is lacking. The objective

  12. Textural features of (18)F-fluorodeoxyglucose positron emission tomography scanning in diagnosing aortic prosthetic graft infection

    NARCIS (Netherlands)

    Saleem, Ben R; Beukinga, Roelof J.; Boellaard, Ronald; Glaudemans, Andor W J M; Reijnen, Michel M P J; Zeebregts, Clark J; Slart, Riemer H J A

    BACKGROUND: The clinical problem in suspected aortoiliac graft infection (AGI) is to obtain proof of infection. Although (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography scanning (PET) has been suggested to play a pivotal role, an evidence-based interpretation is lacking. The

  13. Intravascular stent graft with polyurethane and metallic stent: experimental study

    International Nuclear Information System (INIS)

    Do, Young Soo; Lee, Won Jae; Kim, Boo Kyung Han; Park, Jae Hyung; Lee, Hak Jong; Lee, Sang Hyun; Kim, Sung Hyun; Kim, Jong Won; Ha, Jongwon

    1997-01-01

    To evaluate the usefulness of a new model of the stent graft, and of tissue response related to placement of the stent graft. The stent graft was constructed from polyurethane (Pellethane) graft and Hanaro stent(12mm in diameter, 45mm in length, 10 bends). A stent grafts was inserted into the lower thoracic aorta in each of six adult mongrel dogs(body weight, 12-16kg). At one, two, four, and six months, follow-up studies of angiography and spiral CT angiography were preformed to evaluate wascular patency, vascular stenosis, and thrombus formation. Two dogs were sacrificed at 1month, 2months, and 6months after insertion of the stent graft and macroscopic, light microscopic, and scanning electron microscopic examinations of the aortic segment including the stent graft were performed to evaluate intimal hyperplasia, endothelial growth to the graft, and thrombus formation. During follow-up at one, two, four, and six months, angiography or spiral CT angiography showed 20-100% luminal stenosis or occlusion of the lower thoracic aorta by the thrombus and perigraft leaks in three dogs(50%), and collateral vessels caused by occlusion of the aorta in two (33.3%). On gross examination, there were thrombi of 1-5mm thickness at the graft portions in all dogs, and this thickness gradually increased. The mean thickness of intimal hyperplasia at the stent portion gradually increased from 120μm to 227μm and the mean thickness of intimal hyperplasia at the graft portion from 93μm to 914μm. This thickness was greater at the graft portion than at the stent portion. Scanning electron microscopy showed elliptical endothelial lining on the neointimal surfaces at each end of the graft. Thrombi caused stenosis or occlusion of the stent graft. In order for such a graft to be ideal, further study is needed

  14. Grafting

    Energy Technology Data Exchange (ETDEWEB)

    Garnett, J L [New South Wales Univ., Kensington (Australia). School of Chemistry

    1979-01-01

    The unique value of ionizing radiation for the initiation of grafting to backbone polymers is discussed. The principles of the technique are briefly reviewed. The conditions under which free radicals and ions participate in these reactions are examined. Examples of representative grafting processes are considered to illustrate where the technique can be of potential commercial value to a wide range of industries. The general principles of these grafting reactions are shown to be applicable to radiation induced rapid cure technology such as is provided by electron beam processing facilities. Grafting reactions initiated by UV are also treated and shown to be of importance because of the many similarities in properties of the ionizing radiation and UV systems, also the rapid industrial exploitation of EB and sensitized UV processing technology. Possible future trends in radiation grafting are outlined.

  15. Balloon expandable intraluminal grafting of normal and abnormal renal arteries: Experimental study

    International Nuclear Information System (INIS)

    Palmaz, J.C.; Hayashi, H.; Schatz, R.; Hunter, G.; Tio, F.O.; Garcia, O.

    1986-01-01

    Balloon expandable intraluminal grafts were placed in renal arteries of eight adult dogs and 11 minipigs. The renal arteries were normal in the dogs before graft placement. Two grafts were placed in primary division branches and the rest in the main renal artery. Experimental renal artery stenosis was created in the minipigs by subocclusive ligature of the renal artery with absorbable suture material. Six months later significant renal artery stenoses developed in six pigs and were corrected by graft placement. In the remaining pigs grafts were placed in the opposite normal renal artery because the stenosis caused a small, shrunken kidney in two, and severe spasm or anatomic variations prevented graft placement in three. All grafts remained patent on angiographic and pathologic examinations to a maximum follow-up to 24 weeks

  16. Revascularization of femoral head ischemic necrosis with vascularized bone graft: A CT scan experimental study

    International Nuclear Information System (INIS)

    Gonzalez del Pino, J.; Knapp, K.; Gomez Castresana, F.; Benito, M.

    1990-01-01

    An ischemic necrosis of the femoral head was induced in 15 mongrel adult dogs using the technique described by Gartsman et al. Five weeks later, a free vascularized rib graft was transferred into the previously induced ischemic femoral head. High resolution computed tomographic scanning was used to evaluate revascularization 4, 8 and 12 weeks after grafting. The femoral head exhibited new vessel formation throughout the study. Arterial terminal branches arising from the rib graft medullary and periosteal circulations extended beyond the rib graft, entered the head, and reached the subchondral plate. Even where the rib graft did not replenish the central core of the head, there was vascular supply from the grafted bone's vascular tree. These results suggest that a free vascularized bone graft is able to revascularize an experimentally induced ischemic femoral head necrosis. (orig.)

  17. Evaluation of a Musculoskeletal Model with Prosthetic Knee through Six Experimental Gait Trials

    OpenAIRE

    Kia, Mohammad; Stylianou, Antonis P.; Guess, Trent M.

    2014-01-01

    Knowledge of the forces acting on musculoskeletal joint tissues during movement benefits tissue engineering, artificial joint replacement, and our understanding of ligament and cartilage injury. Computational models can be used to predict these internal forces, but musculoskeletal models that simultaneously calculate muscle force and the resulting loading on joint structures are rare. This study used publicly available gait, skeletal geometry, and instrumented prosthetic knee loading data [1]...

  18. Vancomycin-Rifampin Combination Therapy Has Enhanced Efficacy against an Experimental Staphylococcus aureus Prosthetic Joint Infection

    Science.gov (United States)

    Niska, Jared A.; Shahbazian, Jonathan H.; Ramos, Romela Irene; Francis, Kevin P.; Bernthal, Nicholas M.

    2013-01-01

    Treatment of prosthetic joint infections often involves a two-stage exchange, with implant removal and antibiotic spacer placement followed by systemic antibiotic therapy and delayed reimplantation. However, if antibiotic therapy can be improved, one-stage exchange or implant retention may be more feasible, thereby decreasing morbidity and preserving function. In this study, a mouse model of prosthetic joint infection was used in which Staphylococcus aureus was inoculated into a knee joint containing a surgically placed metallic implant extending from the femur. This model was used to evaluate whether combination therapy of vancomycin plus rifampin has increased efficacy compared with vancomycin alone against these infections. On postoperative day 7, vancomycin with or without rifampin was administered for 6 weeks with implant retention. In vivo bioluminescence imaging, ex vivo CFU enumeration, X-ray imaging, and histologic analysis were carried out. We found that there was a marked therapeutic benefit when vancomycin was combined with rifampin compared with vancomycin alone. Taken together, our results suggest that the mouse model used could serve as a valuable in vivo preclinical model system to evaluate and compare efficacies of antibiotics and combinatory therapy for prosthetic joint infections before more extensive studies are carried out in human subjects. PMID:23917317

  19. Textural features of {sup 18}F-fluorodeoxyglucose positron emission tomography scanning in diagnosing aortic prosthetic graft infection

    Energy Technology Data Exchange (ETDEWEB)

    Saleem, Ben R.; Zeebregts, Clark J. [University of Groningen, University Medical Center Groningen, Department of Surgery, Division of Vascular Surgery, P.O. Box 30 001, Groningen (Netherlands); Beukinga, Roelof J.; Slart, Riemer H.J.A. [University of Groningen, University Medical Center Groningen, Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); University of Twente, Department of Biomedical Photonic Imaging (BMPI), Enschede (Netherlands); Boellaard, Ronald; Glaudemans, Andor W.J.M. [University of Groningen, University Medical Center Groningen, Nuclear Medicine and Molecular Imaging, Groningen (Netherlands); Reijnen, Michel M.P.J. [Rijnstate Hospital, Department of Surgery, Arnhem (Netherlands)

    2017-05-15

    The clinical problem in suspected aortoiliac graft infection (AGI) is to obtain proof of infection. Although {sup 18}F-fluorodeoxyglucose ({sup 18}F-FDG) positron emission tomography scanning (PET) has been suggested to play a pivotal role, an evidence-based interpretation is lacking. The objective of this retrospective study was to examine the feasibility and utility of {sup 18}F-FDG uptake heterogeneity characterized by textural features to diagnose AGI. Thirty patients with a history of aortic graft reconstruction who underwent {sup 18}F-FDG PET/CT scanning were included. Sixteen patients were suspected to have an AGI (group I). AGI was considered proven only in the case of a positive bacterial culture. Positive cultures were found in 10 of the 16 patients (group Ia), and in the other six patients, cultures remained negative (group Ib). A control group was formed of 14 patients undergoing {sup 18}F-FDG PET for other reasons (group II). PET images were assessed using conventional maximal standardized uptake value (SUVmax), tissue-to-background ratio (TBR), and visual grading scale (VGS). Additionally, 64 different {sup 18}F-FDG PET based textural features were applied to characterize {sup 18}F-FDG uptake heterogeneity. To select candidate predictors, univariable logistic regression analysis was performed (α = 0.16). The accuracy was satisfactory in case of an AUC > 0.8. The feature selection process yielded the textural features named variance (AUC = 0.88), high grey level zone emphasis (AUC = 0.87), small zone low grey level emphasis (AUC = 0.80), and small zone high grey level emphasis (AUC = 0.81) most optimal for distinguishing between groups I and II. SUVmax, TBR, and VGS were also able to distinguish between these groups with AUCs of 0.87, 0.78, and 0.90, respectively. The textural feature named short run high grey level emphasis was able to distinguish group Ia from Ib (AUC = 0.83), while for the same task the TBR and VGS were not found to be predictive

  20. Textural features of 18F-fluorodeoxyglucose positron emission tomography scanning in diagnosing aortic prosthetic graft infection.

    Science.gov (United States)

    Saleem, Ben R; Beukinga, Roelof J; Boellaard, Ronald; Glaudemans, Andor W J M; Reijnen, Michel M P J; Zeebregts, Clark J; Slart, Riemer H J A

    2017-05-01

    The clinical problem in suspected aortoiliac graft infection (AGI) is to obtain proof of infection. Although 18 F-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography scanning (PET) has been suggested to play a pivotal role, an evidence-based interpretation is lacking. The objective of this retrospective study was to examine the feasibility and utility of 18 F-FDG uptake heterogeneity characterized by textural features to diagnose AGI. Thirty patients with a history of aortic graft reconstruction who underwent 18 F-FDG PET/CT scanning were included. Sixteen patients were suspected to have an AGI (group I). AGI was considered proven only in the case of a positive bacterial culture. Positive cultures were found in 10 of the 16 patients (group Ia), and in the other six patients, cultures remained negative (group Ib). A control group was formed of 14 patients undergoing 18 F-FDG PET for other reasons (group II). PET images were assessed using conventional maximal standardized uptake value (SUVmax), tissue-to-background ratio (TBR), and visual grading scale (VGS). Additionally, 64 different 18 F-FDG PET based textural features were applied to characterize 18 F-FDG uptake heterogeneity. To select candidate predictors, univariable logistic regression analysis was performed (α = 0.16). The accuracy was satisfactory in case of an AUC > 0.8. The feature selection process yielded the textural features named variance (AUC = 0.88), high grey level zone emphasis (AUC = 0.87), small zone low grey level emphasis (AUC = 0.80), and small zone high grey level emphasis (AUC = 0.81) most optimal for distinguishing between groups I and II. SUVmax, TBR, and VGS were also able to distinguish between these groups with AUCs of 0.87, 0.78, and 0.90, respectively. The textural feature named short run high grey level emphasis was able to distinguish group Ia from Ib (AUC = 0.83), while for the same task the TBR and VGS were not found to be predictive. SUVmax

  1. Textural features of "1"8F-fluorodeoxyglucose positron emission tomography scanning in diagnosing aortic prosthetic graft infection

    International Nuclear Information System (INIS)

    Saleem, Ben R.; Zeebregts, Clark J.; Beukinga, Roelof J.; Slart, Riemer H.J.A.; Boellaard, Ronald; Glaudemans, Andor W.J.M.; Reijnen, Michel M.P.J.

    2017-01-01

    The clinical problem in suspected aortoiliac graft infection (AGI) is to obtain proof of infection. Although "1"8F-fluorodeoxyglucose ("1"8F-FDG) positron emission tomography scanning (PET) has been suggested to play a pivotal role, an evidence-based interpretation is lacking. The objective of this retrospective study was to examine the feasibility and utility of "1"8F-FDG uptake heterogeneity characterized by textural features to diagnose AGI. Thirty patients with a history of aortic graft reconstruction who underwent "1"8F-FDG PET/CT scanning were included. Sixteen patients were suspected to have an AGI (group I). AGI was considered proven only in the case of a positive bacterial culture. Positive cultures were found in 10 of the 16 patients (group Ia), and in the other six patients, cultures remained negative (group Ib). A control group was formed of 14 patients undergoing "1"8F-FDG PET for other reasons (group II). PET images were assessed using conventional maximal standardized uptake value (SUVmax), tissue-to-background ratio (TBR), and visual grading scale (VGS). Additionally, 64 different "1"8F-FDG PET based textural features were applied to characterize "1"8F-FDG uptake heterogeneity. To select candidate predictors, univariable logistic regression analysis was performed (α = 0.16). The accuracy was satisfactory in case of an AUC > 0.8. The feature selection process yielded the textural features named variance (AUC = 0.88), high grey level zone emphasis (AUC = 0.87), small zone low grey level emphasis (AUC = 0.80), and small zone high grey level emphasis (AUC = 0.81) most optimal for distinguishing between groups I and II. SUVmax, TBR, and VGS were also able to distinguish between these groups with AUCs of 0.87, 0.78, and 0.90, respectively. The textural feature named short run high grey level emphasis was able to distinguish group Ia from Ib (AUC = 0.83), while for the same task the TBR and VGS were not found to be predictive. SUVmax was found predictive

  2. Rapamycin treatment is associated with an increased apoptosis rate in experimental vein grafts.

    Science.gov (United States)

    Schachner, Thomas; Oberhuber, Alexander; Zou, Yping; Tzankov, Alexandar; Ott, Harald; Laufer, Günther; Bonatti, Johannes

    2005-02-01

    Rapamycin is an immunosuppressive agent with marked antiproliferative properties and is effective in reducing in stent restenosis and vein graft neointimal hyperplasia. Apoptosis is one mechanism counterbalancing cellular proliferation. We therefore investigated the role of apoptosis in rapamycin treated vein grafts in a mouse model. C57BL6J mice underwent interposition of the inferior vena cava from isogenic donor mice into the common carotid artery using a cuff technique. In the treatment group 200 microg of rapamycin were applied locally in pluronic gel. The control group did not receive local treatment. Vein grafts were harvested at 4 weeks postoperatively and underwent morphometric analysis as well as immunohistochemical analysis for apoptosis (TUNEL). In grafted veins without treatment (controls) neointimal thickness was 50 (12-58) microm at 4 weeks postoperatively. In 200 microg rapamycin treated grafts the neointimal thickness was 17 (5-55) microm. Rapamycin treated vein grafts showed a significantly increased rate of apoptosis in the adventitia as compared with controls (P=0.032). In the neointima the apoptosis rate was lower in both groups with no significant difference between rapamycin treated grafts and controls. We conclude that treatment of experimental vein grafts with rapamycin is associated with an increased apoptosis rate in the vascular wall and a trend towards reduction of neointimal hyperplasia. These results suggest that apoptosis may be a beneficial antiproliferative component for the treatment of vein graft disease.

  3. Validation of a numerical 3-D fluid-structure interaction model for a prosthetic valve based on experimental PIV measurements.

    Science.gov (United States)

    Guivier-Curien, Carine; Deplano, Valérie; Bertrand, Eric

    2009-10-01

    A numerical 3-D fluid-structure interaction (FSI) model of a prosthetic aortic valve was developed, based on a commercial computational fluid dynamics (CFD) software program using an Arbitrary Eulerian Lagrangian (ALE) formulation. To make sure of the validity of this numerical model, an equivalent experimental model accounting for both the geometrical features and the hydrodynamic conditions was also developed. The leaflet and the flow behaviours around the bileaflet valve were investigated numerically and experimentally by performing particle image velocimetry (PIV) measurements. Through quantitative and qualitative comparisons, it was shown that the leaflet behaviour and the velocity fields were similar in both models. The present study allows the validation of a fully coupled 3-D FSI numerical model. The promising numerical tool could be therefore used to investigate clinical issues involving the aortic valve.

  4. An experimental apparatus to simulate body-powered prosthetic usage: Development and preliminary evaluation.

    Science.gov (United States)

    Gao, Fan; Rodriguez, Johanan; Kapp, Susan

    2016-06-01

    Harness fitting in the body-powered prosthesis remains more art than science due to a lack of consistent and quantitative evaluation. The aim of this study was to develop a mechanical, human-body-shaped apparatus to simulate body-powered upper limb prosthetic usage and evaluate its capability of quantitative examination of harness configuration. The apparatus was built upon a torso of a wooden mannequin and integrated major mechanical joints to simulate terminal device operation. Sensors were used to register cable tension, cable excursion, and grip force simultaneously. The apparatus allowed the scapula to move up to 127 mm laterally and the load cell can measure the cable tension up to 445 N. Our preliminary evaluation highlighted the needs and importance of investigating harness configurations in a systematic and controllable manner. The apparatus allows objective, systematic, and quantitative evaluation of effects of realistic harness configurations and will provide insightful and working knowledge on harness fitting in upper limb amputees using body-powered prosthesis. © The International Society for Prosthetics and Orthotics 2015.

  5. Cognitive vision system for control of dexterous prosthetic hands: Experimental evaluation

    Directory of Open Access Journals (Sweden)

    Došen Strahinja

    2010-08-01

    Full Text Available Abstract Background Dexterous prosthetic hands that were developed recently, such as SmartHand and i-LIMB, are highly sophisticated; they have individually controllable fingers and the thumb that is able to abduct/adduct. This flexibility allows implementation of many different grasping strategies, but also requires new control algorithms that can exploit the many degrees of freedom available. The current study presents and tests the operation of a new control method for dexterous prosthetic hands. Methods The central component of the proposed method is an autonomous controller comprising a vision system with rule-based reasoning mounted on a dexterous hand (CyberHand. The controller, termed cognitive vision system (CVS, mimics biological control and generates commands for prehension. The CVS was integrated into a hierarchical control structure: 1 the user triggers the system and controls the orientation of the hand; 2 a high-level controller automatically selects the grasp type and size; and 3 an embedded hand controller implements the selected grasp using closed-loop position/force control. The operation of the control system was tested in 13 healthy subjects who used Cyberhand, attached to the forearm, to grasp and transport 18 objects placed at two different distances. Results The system correctly estimated grasp type and size (nine commands in total in about 84% of the trials. In an additional 6% of the trials, the grasp type and/or size were different from the optimal ones, but they were still good enough for the grasp to be successful. If the control task was simplified by decreasing the number of possible commands, the classification accuracy increased (e.g., 93% for guessing the grasp type only. Conclusions The original outcome of this research is a novel controller empowered by vision and reasoning and capable of high-level analysis (i.e., determining object properties and autonomous decision making (i.e., selecting the grasp type and

  6. Scintigraphic follow up of autologous splenic grafts: An experimental and clinical study

    International Nuclear Information System (INIS)

    Reilmann, H.; Creutzig, H.; Pabst, R.; Kamran, D.

    1984-01-01

    The risk of overwhelming sepsis in splenectomized patients is well known and autotransplantation of splenic tissue might be considered as a prophylactic approach. Little is known, however, of the success of grafting in man. In six patients with autologous grafts after emergency splenectomy the ''trapping function'' (TF) was measured by sequential scintigraphy with heat damaged red cells every third month. To correlate TF with blood flow and histology, different experiments were done in pigs: ligation of the splenic artery or partial splenectomy or total splenectomy with grafting of fragments either subfascially or in the greater momentum. TF, blood flow with Rb-86 and immune response was measured at different times after surgery. Remnants left at the main vessels did not grow, while splenic tissue left at smaller vessels increased in size. There were great differences in blood flow per gram splenic tissue, but a significant correlation between TF and blood flow. All experimental grafts showed a normal function both of the white and the red pulp. In patients there was a growth of grafts in four, while in two no TF could be measured. TF is an indicator of relative blood flow to splenic grafts and therefore useful in the follow up of grafted patients

  7. Graft infections after surgical aortic reconstructions

    NARCIS (Netherlands)

    Berger, P.

    2015-01-01

    Prosthetic vascular grafts are frequently used to reconstruct (part) of the aorta. Every surgical procedure caries a certain risk for infection and when a prosthetic aortic graft is implanted, this may lead to an aortic graft infection (AGI). Endovascular techniques have gradually replaced open

  8. The relevance of aortic endograft prosthetic infection

    NARCIS (Netherlands)

    Cernohorsky, Paul; Reijnen, Michel M. P. J.; Tielliu, Ignace F. J.; van Sterkenburg, Steven M. M.; van den Dungen, Jan J. A. M.; Zeebregts, Clark J.

    Background: Vascular prosthetic graft infection is a severe complication after open aortic aneurysm repair. Reports of infected endografts are scarce. General treatment consensus with infected graft material is that it should be removed completely. The objective of this study was to describe the

  9. Polyhydroxybutyrate/valerate/polycaprolactone small-diameter vascular graft: Experimental study of integration into organism

    Energy Technology Data Exchange (ETDEWEB)

    Antonova, L. V., E-mail: antonova.la@mail.ru; Burago, A. Yu.; Matveeva, V. G.; Velikanova, E. A.; Mukhamadiyarov, R. A.; Glushkova, T. V.; Kudryavtseva, Y. A.; Barbarash, O. L.; Barbarash, L. S. [Research Institute for Complex Issues of Cardiovascular Diseases, Kemerovo (Russian Federation); Mironov, A. V. [Kemerovo Cardiology Dispensary, Kemerovo (Russian Federation)

    2015-10-27

    We prepared polyhydroxybutyrate/valerate (PHBV)/polylcaprolactone (PCL) small-diameter vascular grafts using electrospinning. Surface structure was assessed by scanning electron microscopy whilst physicomechanical properties were investigated by longitudinal uniaxial tension testing. Patency of grafts implanted into the rat abdominal aorta was evaluated using a Doppler ultrasonography at 2 week, 1 month and 12 month postimplantation. In addition, we assessed local histological features, along with IL-1β, IL-2, IL-4, IL-10, TNFa, TGF-β1, and VEGF serum levels. We revealed that only 2 (25%) grafts were not thrombosed at 2 week and 1 month postimplantation. However, at 12 month postimplantation a satisfactory histological pattern was observed in 50% of all cases, and we detected a monolayer of endothelial cells on the inner graft surface in half the cases. Regarding other grafts, we revealed minor connective tissue hyperplasia in 41.7% of the grafts and an inflammatory infiltrate in the part of the arterial wall in 8.3% of the grafts. We found that the IL-1β serum level was 3.5-fold higher in the group of experimental rats at 12 month postimplantation (p < 0.01). In addition, the IL-2 and IL-4 serum levels at 12 month postimplantation were 2- and 2.8-fold higher as compared to short-term implantation (2 weeks and 1 month) and control rats (p < 0.05) whilst the IL-10 serum level at 1 and 12 month postimplantation was more than 100-fold higher in comparison with 2 week postimplantation and control rats (p < 0.001). Serum VEGF was detected only at 12 month postimplantation. All in all, we created a biocompatible PHBV/PCL small-diameter vascular graft with a high surface area to volume ratio. A long-term patency of biodegradable vascular grafts after implantation into the rat abdominal aorta and the absence of a considerable immune response confirmed a high biocompatibility of such construct and the possibility of its use as a vascular graft.

  10. Prefabrication of a vascularized nerve graft by vessel implantation: preliminary report of an experimental model.

    Science.gov (United States)

    Cavadas, P C; Vera-Sempere, F J

    1994-01-01

    Regeneration through vascularized nerve grafts (VNG) seems to be better than nonvascularized nerve grafts (NVNG), especially in hostile beds. We report on an experimental technique of prefabrication of VNG by direct vessel implantation. An arteriovenous fistula was created in the groin region with autologous vein grafts in the Wistar rat model, and implanted into the sciatic nerve. Five weeks later the sciatic VNG was elevated on the prefabricated pedicle. The flap was free-transferred orthotopically over a silicone sheet to impede plasmatic imbibition. Flap viability at 3 days was complete. India ink injection of the AV fistula resulted in capillary ink filling within the nerve and surrounding tissues. Histologic sections of the flap were examined, revealing its neovascularity. In an ongoing study, the regeneration through this prefabricated VNG is being compared to native VNG.

  11. Experimental Models Used in Fat Grafting Research for Volume Augmentation in Soft Tissue Reconstruction

    Directory of Open Access Journals (Sweden)

    Jorge Lujan-Hernandez

    2017-09-01

    Full Text Available As the popularity of fat grafting research increases, animal models are being used as the source of pre-clinical experimental information for discovery and to enhance techniques. To date, animal models used in this research have not been compared to provide a standardized model. We analyzed publications from 1968–2015 to compare published accounts of animal models in fat grafting research. Data collected included: species used, graft characteristics (donor tissue, recipient area, amount injected, injection technique, time of sacrifice and quantification methods. Mice were most commonly used (56% of studies, with the “athymic nude” strain utilized most frequently (44%. Autologous fat was the most common source of grafted tissue (52%. Subcutaneous dorsum was the most common recipient site (51%. On average, 0.80±0.60 mL of fat was grafted. A single bolus technique was used in 57% of studies. Fat volume assessment was typically completed at the end of the study, occurring at less than 1 week to one year. Graft volume was quantified by weight (63%, usually in conjunction with another analysis. The results demonstrate the current heterogeneity of animal models in this research. We propose that the research community reach a consensus to allow better comparison of techniques and results. One example is the model used in our laboratory and others; this model is described in detail. Eventually, larger animal models may better translate to the human condition but, given increased financial costs and animal facility capability, should be explored when data obtained from small animal studies is exhausted or inconclusive.

  12. Prosthetic Engineering

    Science.gov (United States)

    ... the household and community environments may lead to falls and injuries. This research aims to develop an ankle that can invert and evert and thereby control the center of pressure under the prosthetic foot; enhancing balance and stability of lower limb amputees. Foot-Ankle ...

  13. Evaluation of {sup 99m}Tc-UBI 29-41 scintigraphy for specific detection of experimental Staphylococcus aureus prosthetic joint infections

    Energy Technology Data Exchange (ETDEWEB)

    Sarda-Mantel, Laure; Meulemans, Alain; Vrigneaud, Jean-Marc; Raguin, Olivier; Lebtahi, Rachida; Guludec, Dominique Le [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); Service de Medecine Nucleaire, AP-HP, Groupe Hospitalier Bichat-Beaujon, Paris (France); INSERM, U773, Paris (France); Saleh-Mghir, Azzam [Universite Versailles-St-Quentin, EA 3647, Garches (France); Welling, Mick M. [Leiden University Medical Center (LUCM), Department of Radiology, Section of Nuclear Medicine, Leiden (Netherlands); Hervatin, Florence [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); CEA, DSV/DRM/SHFJ, Orsay (France); Martet, Genevieve [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); INSERM, U773, Paris (France); Chau, Francoise [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); Universite Denis Diderot Paris 7, EA 3964, Paris (France)

    2007-08-15

    {sup 99m}Tc-UBI 29-41 (UBI), an antimicrobial peptide, specifically targets bacteria. We tested the ability of UBI to discriminate between infected and uninfected prosthetic joints using a rabbit model previously validated. Left knee arthroplasty was performed on 20 New Zealand rabbits, then 10{sup 7} cfu of S. aureus (n = 12) or sterile saline (n = 8) was injected into the joint. On days 9 and 20 after surgery, planar UBI scintigraphy was performed in six infected and four uninfected rabbits, 1 h and 4 h p.i. (150 MBq), on a gamma camera. Operated-to-normal knee activity ratio (ONKR) was calculated on each scintigram. Then, after sacrifice, tissue samples of both knees were counted in a gamma counter. One rabbit injected with sterile saline had cutaneous infection at sacrifice and was excluded from analysis. ONKR was higher in infected than in uninfected animals 4 h p.i. 20 days after surgery: 1.75 {+-} 0.48 vs 1.13 {+-} 0.11, p = 0.04. From 1 h to 4 h p.i., ONKR increased in 9/12 infected and 0/7 uninfected animals. According to UBI uptake intensity and kinetics, scintigraphy was truly positive in all infected cases on day 9 and in four of six infected cases on day 20. It was truly negative in two of three sterile inflamed prosthetic knees on day 9, and in all cases on day 20. Biodistribution studies revealed increased UBI uptake in periprosthetic tissues in all animals 9 days after surgery, and only in infected animals on day 20. In this experimental study, {sup 99m}Tc-UBI 29-41 scintigraphy permitted the early detection of acute prosthetic joint infection, and exclusion of infection in chronic sterile prosthetic joint inflammation. (orig.)

  14. Evaluation of 99mTc-UBI 29-41 scintigraphy for specific detection of experimental Staphylococcus aureus prosthetic joint infections

    International Nuclear Information System (INIS)

    Sarda-Mantel, Laure; Meulemans, Alain; Vrigneaud, Jean-Marc; Raguin, Olivier; Lebtahi, Rachida; Guludec, Dominique Le; Saleh-Mghir, Azzam; Welling, Mick M.; Hervatin, Florence; Martet, Genevieve; Chau, Francoise

    2007-01-01

    99m Tc-UBI 29-41 (UBI), an antimicrobial peptide, specifically targets bacteria. We tested the ability of UBI to discriminate between infected and uninfected prosthetic joints using a rabbit model previously validated. Left knee arthroplasty was performed on 20 New Zealand rabbits, then 10 7 cfu of S. aureus (n = 12) or sterile saline (n = 8) was injected into the joint. On days 9 and 20 after surgery, planar UBI scintigraphy was performed in six infected and four uninfected rabbits, 1 h and 4 h p.i. (150 MBq), on a gamma camera. Operated-to-normal knee activity ratio (ONKR) was calculated on each scintigram. Then, after sacrifice, tissue samples of both knees were counted in a gamma counter. One rabbit injected with sterile saline had cutaneous infection at sacrifice and was excluded from analysis. ONKR was higher in infected than in uninfected animals 4 h p.i. 20 days after surgery: 1.75 ± 0.48 vs 1.13 ± 0.11, p = 0.04. From 1 h to 4 h p.i., ONKR increased in 9/12 infected and 0/7 uninfected animals. According to UBI uptake intensity and kinetics, scintigraphy was truly positive in all infected cases on day 9 and in four of six infected cases on day 20. It was truly negative in two of three sterile inflamed prosthetic knees on day 9, and in all cases on day 20. Biodistribution studies revealed increased UBI uptake in periprosthetic tissues in all animals 9 days after surgery, and only in infected animals on day 20. In this experimental study, 99m Tc-UBI 29-41 scintigraphy permitted the early detection of acute prosthetic joint infection, and exclusion of infection in chronic sterile prosthetic joint inflammation. (orig.)

  15. Long-Term Outcomes of Catheter-Directed Thrombolysis for Acute Lower Extremity Occlusions of Native Arteries and Prosthetic Bypass Grafts

    NARCIS (Netherlands)

    Schrijver, A. Marjolein; de Vries, Jean Paul P M; van den Heuvel, Daniel A F; Moll, Frans L.

    2016-01-01

    Background Catheter-directed thrombolysis is a well-accepted treatment for acute lower extremity occlusions of native arteries and bypass grafts. Several variables that affect outcomes of thrombolysis have been identified. The hypothesis of this study was that the long-term outcome after

  16. Concepts to optimize stent-grafting of abdominal aortic aneurysms based on results of experimental studies

    International Nuclear Information System (INIS)

    Chavan, A.; Kirchhoff, T.; Baus, S.; Galanski, M.; Pichlmaier, M.

    2001-01-01

    Purpose. In the endoluminal therapy of abdominal aortic aneurysms, a short proximal aneurysm neck, endoleaks and the large size and stiffness of the introducer systems are responsible for many of the complications and sub-optimal outcomes. The purpose of the present review article is to to suggest strategies to minimize these complications based on the results of experimental studies in animals. Material and methods. After implanting various types of stents across the renal artery origins, the functional and morphological changes in the kidneys and renal vessels were studied by various authors. In order to prevent progressive widening of the proximal aneurysmal neck and graft dislocation, Sonesson et al. performed a laparoscopic banding around the proximal neck in pigs. To study the effects of endoleaks, Marty, Schurink and Pitton carried out pressure measurements in experimental aneurysms with and without endoleaks. Sakaguchi and Pavcnik developed the 'Twin-tube endografts' (TTEG) and the 'Bifurcated drum occluder endografts' (BDOEG) and tested them in dogs. Results. Up to 3 months after suprarenal stent placement, Chavan et al. detected no significant fall in the mean inulin clearance in sheep (140±46 ml/min before, 137±58 ml/min after). Nasim et al. and Malina et al. reported similar observations with respect to renal function. Suprarenal fixation may result in isolated thrombotic occlusions of the renal arteries and microinfarcts in the kidneys. Mean aortic diameters at the level of banding were significantly smaller in the animals with aortic banding as opposed to those in the control group without banding (8 mm vs 11 mm, p=0.004). The banding caused a secure proximal fixation of the stent-graft. Persistent endoleaks resulted in significantly higher intraaneurysmal pressures. Although the TTEG and the BDOEG stent-grafts required smaller sheaths, occlusions were observed in 8% (TTEG) and 60% (BDOEG) of the graft limbs. (orig.) [de

  17. Experimental substantiation of the design of a prosthetic heart valve for «valve-in-valve» implantation

    Directory of Open Access Journals (Sweden)

    K. Yu. Klyshnikov

    2017-01-01

    Full Text Available The aim of the study was to perform a series of in vitro tests of a prototype of the developing heart valve prosthesis to evaluate its functional characteristics. Materials and methods. In this work we have used the frames and full prototypes of the prosthesis, consisting of a stent-like stainless steel support frame with mounted biological leaflets and cover. The authors evaluated the calculated and experimental forces necessary for the displacement of the sutureless implanted prosthesis using the test machine under uniaxial tension. The risk of defects and damages to the supporting framework as a result of implantation was evaluated by scanning electron microscopy. The hydrodynamic characteristics of the prosthesis were investigated under physiological conditions and «valvein-valve» implantation. Evaluation of the ergonomics and applicability of the proposed construction on the cadaver heart model of cattle was carried out. Results. As a result of the forces assessment, it was found that the force required to shear the prosthesis was 3.12 ± 0.37 N, while the calculated value was 1.7 N, which is significantly lower than the obtained value. The comparison of the images obtained with small and large magnifications demonstrated the absence of critical surface defects. Additional analysis under the super-large magnifications also did not reveal problem areas. During the hydrodynamic study, it was shown that the average transplant gradient increased slightly from 2.8–3.4 to 3.2–4.5 mm Hg for the initial prosthesis and the «valve-in-valve» complex, respectively. The decrease of the effective orifice area was 6–9% relative to the initial one. Evaluation of the implantation technique demonstrated the consistency of the approach: the use of the developed holder in combination with the balloon implantation system made it possible to position the prosthesis throughout the procedure. Conclusion. The series of tests demonstrates the consistency

  18. Experimental Study of Real-Time Classification of 17 Voluntary Movements for Multi-Degree Myoelectric Prosthetic Hand

    Directory of Open Access Journals (Sweden)

    Trongmun Jiralerspong

    2017-11-01

    Full Text Available The myoelectric prosthetic hand is a powerful tool developed to help people with upper limb loss restore the functions of a biological hand. Recognizing multiple hand motions from only a few electromyography (EMG sensors is one of the requirements for the development of prosthetic hands with high level of usability. This task is highly challenging because both classification rate and misclassification rate worsen with additional hand motions. This paper presents a signal processing technique that uses spectral features and an artificial neural network to classify 17 voluntary movements from EMG signals. The main highlight will be on the use of a small set of low-cost EMG sensor for classification of a reasonably large number of hand movements. The aim of this work is to extend the capabilities to recognize and produce multiple movements beyond what is currently feasible. This work will also show and discuss about how tailoring the number of hand motions for a specific task can help develop a more reliable prosthetic hand system. Online classification experiments have been conducted on seven male and five female participants to evaluate the validity of the proposed method. The proposed algorithm achieves an overall correct classification rate of up to 83%, thus, demonstrating the potential to classify 17 movements from 6 EMG sensors. Furthermore, classifying 9 motions using this method could achieve an accuracy of up to 92%. These results show that if the prosthetic hand is intended for a specific task, limiting the number of motions can significantly increase the performance and usability.

  19. Grafted natural polymer as new drag reducing agent: An experimental approach

    Directory of Open Access Journals (Sweden)

    Abdulbari Hayder A.

    2012-01-01

    Full Text Available The present investigation introduces a new natural drag reducing agent which has the ability to improve the flow in pipelines carrying aqueous or hydrocarbon liquids in turbulent flow. Okra (Abelmoschus esculentus mucilage drag reduction performance was tested in water and hydrocarbon (gas-oil media after grafting. The drag reduction test was conducted in a buildup closed loop liquid circulation system consists of two pipes 0.0127 and 0.0381 m Inside Diameter (ID, four testing sections in each pipe (0.5 to 2.0 m, tank, pump and pressure transmitters. Reynolds number (Re, additive concentration and the transported media type (water and gas-oil, were the major drag reduction variables investigated. The experimental results show that, new additive drag reduction ability is high with maximum percentage of drag reduction (%Dr up to 60% was achieved. The experimental results showed that the drag reduction ability increased by increasing the additive concentration. The %Dr was found to increase by increasing the Re by using the water-soluble additive while it was found to decrease by increasing the Re when using the oil-soluble additive. The %Dr was higher in the 0.0381 m ID pipe. Finally, the grafted and natural mucilage showed high resistance to shear forces when circulated continuously for 200 seconds in the closed-loop system.

  20. Graft infections after surgical aortic reconstructions

    OpenAIRE

    Berger, P.

    2015-01-01

    Prosthetic vascular grafts are frequently used to reconstruct (part) of the aorta. Every surgical procedure caries a certain risk for infection and when a prosthetic aortic graft is implanted, this may lead to an aortic graft infection (AGI). Endovascular techniques have gradually replaced open surgical reconstructions as first line of treatment for aorto-iliac diseases. Nowadays, open reconstructions are primarily reserved for patients unsuitable for endovascular reconstructions or for redo ...

  1. The effect of butyric acid with autogenous omental graft on healing of experimental Achilles tendon injury in rabbits.

    Science.gov (United States)

    Jahani, S; Moslemi, H R; Dehghan, M M; Sedaghat, R; Mazaheri Nezhad, R; Rezaee Moghaddam, D

    2015-01-01

    In this study, the role of local injection of butyric acid (BA) with autogenous omental graft was evaluated in healing of experimental Achilles tendon injury in rabbits. Nine adult male New Zealand rabbits were anesthetized and a partial thickness tenotomy was created on both hindlimbs. In treated group, omental graft was secured in place using BA soaked polygalactin 910 suture. In control group, the graft was sutured without BA. Butyric acid and normal saline were injected daily to treatment and control groups for three days, respectively. Based on the findings, on day 15 after injury, the tendon sections showed that healing rate in BA treated group was higher than that in control group. Furthermore, at days 28 and 45, comparison between BA treated and control groups demonstrated that BA increased the healing rate but with no significance. In summary, results of this study show that application of BA with autogenous omental graft can improve healing process of damaged Achilles tendon.

  2. Comprehensive Comparison of the Performance of Autogenous Brachial-Basilic Transposition Arteriovenous Fistula and Prosthetic Forearm Loop Arteriovenous Graft in a Multiethnic Asian Hemodialysis Population

    Directory of Open Access Journals (Sweden)

    Koy Min Chue

    2016-01-01

    Full Text Available Aim. For patients who have exhausted cephalic vein arteriovenous fistula (AVF options, controversy exists on whether brachial-basilic AVF with transposition (BBTAVF or a forearm arteriovenous graft (AVG should be the next vascular access of choice. This study compared the outcomes of these two modalities. Methods. A retrospective study of 122 Asian multiethnic patients who underwent either a BBTAVF (81 or an AVG (41. Maturation time and intervention rates were analyzed. Functional primary, secondary, and overall patency rates were evaluated. Results. The maturation time for BBTAVFs was significantly longer than AVGs. There was also a longer deliberation time before surgeons abandon a failing BBTAVF compared to an AVG. Both functional primary and secondary patency rates were significantly higher in the BBTAVF group at 1-year follow-up: 73.2% versus 34.1% (p<0.001 and 71.8% versus 54.3% (p=0.022, respectively. AVGs also required more interventions to maintain patency. When maturation rates were considered, the overall patency of AVGs was initially superior in the first 25 weeks after creation and then became inferior afterwards. Conclusion. BBTAVFs had superior primary and functional patency and required less salvage interventions. The forearm AVG might have a role in patients who require early vascular access due to complications from central venous catheters or with limited life expectancy.

  3. Current Role of Imaging in Diagnosing Aortic Graft Infections

    NARCIS (Netherlands)

    Bruggink, Janneke L. M.; Slart, Riemer H. J. A.; Pol, Jillis A.; Reijnen, Michel M. P. J.; Zeebregts, Clark J.

    2011-01-01

    Vascular prosthetic graft infection is a rare but serious complication after aortic graft replacement, with high morbidity and mortality rates. Therefore, adequate diagnostics are needed to detect and treat these infections as early as possible. Several imaging modalities provide different

  4. Ceacam1 separates graft-versus-host-disease from graft-versus-tumor activity after experimental allogeneic bone marrow transplantation.

    Directory of Open Access Journals (Sweden)

    Sydney X Lu

    Full Text Available Allogeneic bone marrow transplantation (allo-BMT is a potentially curative therapy for a variety of hematologic diseases, but benefits, including graft-versus-tumor (GVT activity are limited by graft-versus-host-disease (GVHD. Carcinoembryonic antigen related cell adhesion molecule 1 (Ceacam1 is a transmembrane glycoprotein found on epithelium, T cells, and many tumors. It regulates a variety of physiologic and pathological processes such as tumor biology, leukocyte activation, and energy homeostasis. Previous studies suggest that Ceacam1 negatively regulates inflammation in inflammatory bowel disease models.We studied Ceacam1 as a regulator of GVHD and GVT after allogeneic bone marrow transplantation (allo-BMT in mouse models. In vivo, Ceacam1(-/- T cells caused increased GVHD mortality and GVHD of the colon, and greater numbers of donor T cells were positive for activation markers (CD25(hi, CD62L(lo. Additionally, Ceacam1(-/- CD8 T cells had greater expression of the gut-trafficking integrin α(4β(7, though both CD4 and CD8 T cells were found increased numbers in the gut post-transplant. Ceacam1(-/- recipients also experienced increased GVHD mortality and GVHD of the colon, and alloreactive T cells displayed increased activation. Additionally, Ceacam1(-/- mice had increased mortality and decreased numbers of regenerating small intestinal crypts upon radiation exposure. Conversely, Ceacam1-overexpressing T cells caused attenuated target-organ and systemic GVHD, which correlated with decreased donor T cell numbers in target tissues, and mortality. Finally, graft-versus-tumor survival in a Ceacam1(+ lymphoma model was improved in animals receiving Ceacam1(-/- vs. control T cells.We conclude that Ceacam1 regulates T cell activation, GVHD target organ damage, and numbers of donor T cells in lymphoid organs and GVHD target tissues. In recipients of allo-BMT, Ceacam1 may also regulate tissue radiosensitivity. Because of its expression on both the

  5. The implantation of separating aortic stent-graft into the canine thoracic aorta: an experimental study

    International Nuclear Information System (INIS)

    Xia Jinguo; Shi Haibin; Yang Zhengqiang; Li Chao; Liu Sheng; Zu Qingquan; Li Linsun

    2011-01-01

    Objective: to assess the technical feasibility of implanting separating stent-graft into the canine thoracic aorta and to study its biocompatibility. Methods: Twelve adult dogs were randomly and equally divided into three groups. The right femoral artery was cut open, through which the separating stent-graft was inserted and deployed in the canine thoracic aorta, with the proximal end of the graft being quite close to the origin of the left subclavian artery. the technical feasibility of the deployment process was assessed. Angiography was performed at 4, 8 and 12 weeks after stent-graft placement to evaluate the position and patency of the stent-graft. Then the dogs were sacrificed and the specimens were collected for pathologic study. Both gross and microscopic examinations were made to evaluate the fixation of the stent-graft with the vessel wall, the endothelialization of stent-graft surface and the pathologic changes of the vascular wall. Results: A total of ten separating stent-grafts were successfully deployed in the canine thoracic aorta, no migration or deformation occurred. One dog died of massive bleeding due to the rupture of the right femoral artery which occurred when the delivery system containing the inner bare stent was inserted through the right femoral artery. Death occurred in another dog as a result of the ascending aorta rupture caused by the migration of outer-layer stent-graft. Angiography was conducted at 4, 8 and 12 weeks after stent-graft placement. No migration, deformation, rupture or stenosis of the implanted stent-grafts were observed. The formation of intima on the inner surface of the bare stent appeared at 4 weeks, which became more and more obvious with the time passing, and at 12 weeks complete endothelialization of stent-graft surface was observed. Conclusion: Technically, it is feasible to deploy the separating aortic stent-graft into the canine thoracic aorta. Moreover, the separating aortic stent-graft carries excellent

  6. Theoretical and experimental studies for selective removal of antimony from zircaloy using thiourea grafted polystyrene adsorbent. Contributed Paper MS-01

    International Nuclear Information System (INIS)

    Arora, Jyotsna S.; Gaikar, Vilas G.

    2014-01-01

    During the dissolution step in nuclear fuel reprocessing, hulls consisting of essentially zircaloy clad are produced as high active solid waste. For recovery and reuse of zircaloy from this solid waste, 58 Co and 125 Sb which are present as the activation products of cobalt and tin in zircaloy tubes need to be separated. The present work involves selective sorption of antimony on thiourea grafted polymeric adsorbent in the presence of cobalt and zirconium. The effect of pH for the optimum uptake of antimony ions was studied. Since the variation in pH influences the antimony species formed in the solution, density functional theoretical (DFT) studies were performed in order to understand the complexation of the metal species with the grafted adsorbent at the molecular level. The highest occupied molecular orbital (HOMO) of the adsorbent which is located on S atom of loaded thiourea interacts with lowest unoccupied molecular orbital (LUMO) of Sb(V). The grafted adsorbent exhibits higher interaction with antimony species as compared to cobalt and zirconium. The metal-S bond distances are in good agreement with the XRD values for similar systems. Including the effect of solvation model helps in validation of simulation results with experimental adsorption data suggesting the application of thiourea grafted adsorbent for antimony separation. (author)

  7. Effects of Hydroxyapatite on Bone Graft Resorption in an Experimental Model of Maxillary Alveolar Arch Defects

    Directory of Open Access Journals (Sweden)

    Ozgur Pilanci

    2013-06-01

    Full Text Available Most commonly used treatments use autologous bone grafts to address bony defects in patients with cleft palate. Major disadvantages of autogenous bone grafts include donor site morbidity and resorption. Suggestions to overcome such problems include biomaterials that can be used alone or in combination with bone. We examined the effect of hydroxyapatite cement on bone graft resorption in a rabbit maxillary alveolar defect model. We divided 16 young adult albino New Zealand rabbits into two groups. A defect 1 cm wide was created in each rabbit's maxillary arch. In Group 1, the removed bone was disrupted, and the pieces were replaced in the defect. In the other group, the pieces were replaced after mixing (1:1 with hydroxyapatite cement. Quantitative computed tomographic evaluation of these grafts was performed in axial and coronal planes for each rabbit at 2 and 12 weeks. In axial images at 12 weeks, the group without cement showed mean bone resorption of 15%. In the cement group, a mean volumetric increase of 68% was seen. No resorption occurred when bone grafts were mixed with hydroxyapatite cement. [Arch Clin Exp Surg 2013; 2(3.000: 170-175

  8. Repair of bile duct injuries with Gore-Tex vascular grafts: experimental study in dogs.

    Science.gov (United States)

    Gómez, Néstor A; Alvarez, Ludwig R; Mite, Alfredo; Andrade, Jean P; Alvarez, José R; Vargas, Paola E; Tomalá, Nancy E; Vivas, Alex F; Zapatier, Jorge A

    2002-01-01

    Bile duct injury is the most feared complication related to biliary tract operations. The goal of this investigation was to offer an alternative treatment that might prevent this complication. Twelve mongrel dogs, thin-walled FEP-ringed Gore-Tex vascular grafts, and Gore-Tex sutures were used in this study. The dogs were randomized into three groups of four according to the length of time of graft implantation: group 1 = 1 month; group 2 = 2 months; and group 3 = 3 months. During the first part of the study, a biliary injury was induced by ligating the middle choledocus after performing a conventional cholecystectomy. During the second part of the study, biliodigestive and biliobiliary anastomosis were performed using Gore-Tex vascular grafts prior to resection of the stenotic area. Initially, an increase in serum bilirubin and alkaline phosphatase levels was noted. Two weeks later, after implantation of the grafts, these values returned to normal. Thin-walled FEP-ringed Gore-Tex vascular grafts were found to be useful in the repair of bile duct injuries, especially in complete transections of the common bile duct. The ductility and flexibility of the material allows any type of anastomosis to be performed, especially when bile duct-gut anastomosis is technically difficult.

  9. Can a graft be placed over a flap in complex hypospadias surgery? An experimental study in rabbits

    Directory of Open Access Journals (Sweden)

    Ricardo Marcondes de Mattos

    Full Text Available ABSTRACT Purpose: To develop a rabbit experimental study to test the hypothesis that surgical repair of hypospadias with severe ventral curvatures might be completed in one stage, if a graft, such as buccal mucosa, could be placed over the tunica vaginalis flap used in corporoplasty for ventral lengthening, with the addition of an onlay preputial island flap to complete the urethroplasty. Materials and methods: The experimental procedure with rabbits included a tunica vaginalis flap for reconstruction of the corpora after corporotomy, simulating a ventral lengthening operation. A buccal mucosa graft was placed directly on top of the flap, and the urethroplasty was completed with an onlay preputial island flap. Eight rabbits were divided into 4 groups, sacrificed at 2, 4, 8 and 12 weeks postoperatively, and submitted to histological evaluation. Results: We observed a large number of complications, such as fistula (75%, urinary retention (50% and stenosis (50%. There were two deaths related to the procedure. Histological evaluation demonstrated a severe and persistent inflammatory reaction. No viable tunica vaginalis or buccal mucosa was identified. Conclusions: In this animal model, the association of a buccal mucosa graft over the tunica vaginalis flap was not successful, and resulted in complete loss of both tissues.

  10. Prevention of Prosthetic Dentistry

    Directory of Open Access Journals (Sweden)

    Eremin O.V.

    2011-03-01

    Full Text Available Prevention in prosthetic dentistry is not just a regular oral hygiene and the prevention of caries in the early stages of its development. The initial goal of orthopedic and dental should be the ability to convey to the patient's sense of pros-thetics that proteziruya one saved more. An example is included prosthetic dental arch defects with bridges or single artificial crowns on implants that will prevent movement of teeth and the continuity of the dentition

  11. Morphological experimental study of bone stress at the interface acetabular bone/prosthetic cup in the bipolar hip prosthesis.

    Science.gov (United States)

    Anuşca, D; Pleşea, I E; Iliescu, N; Tomescu, P; Poenaru, F; Dascălu, V; Pop, O T

    2006-01-01

    By calculating the tension and distortion of the elements composing the bipolar prosthesis under extreme conditions encountered in real life using a special post-processing program, we established the variation curves of the contact pressure at the hip bone-cup, armor-cup and cup-femoral head interface. By comparing the data obtained from all the examined cases, important conclusions were drawn regarding the influence of tension and pressure distribution on the structural integrity and biomechanics of the prosthesis, as well as the acetabular wear and tear, in order to assess its reliability. The experimentally determined tension and distortion status at the acetabular bone-metal armour interface, lead to the wear and tear phenomenon, which can be explained by three mechanisms and theories incompletely reflecting the overall process. The histopathologic study of the acetabular bone tissue using FEM (finite elements method) on surgically removed specimens will probably lead to the identification of a series of factors that could reduce the rate of the wear and tear process.

  12. The processing of sheepskin for use as a dermal collagen graft--an experimental study

    NARCIS (Netherlands)

    van Gulik, T. M.; Klopper, P. J.

    1987-01-01

    In search of a biological mesh-prosthesis, sheepskin was processed according to established methods in the manufacture of leather. The dermal collagen fibre-mesh of sheepskin was purified by a proteolytic enzyme treatment after which the skins were split, providing a split-skin graft corresponding

  13. Application of a vascular graft material (Solcograft-P) in experimental surgery.

    Science.gov (United States)

    Nemes, A; Acsády, G; Fraefel, W; Lichti, H; Monos, E; Oertli, R; Somogyi, E; Sótonyi, P

    1985-09-01

    The implantation and post-implantation behaviour of a Solcograft-P vascular prosthesis in the aortic, aorto-iliac, carotid and vena caval positions in dogs was studied up to 100 d post-surgery in order to assess the suitability of this vascular material for use in man. Solcograft-P is prepared from the carotid arteries of calves by crosslinking the collagen stroma using adipyl dichloride. During the postoperative follow-up period of 3 month, 100% of the aortal grafts, 80% of the aorto-iliac bypasses, 60% of the vena caval grafts and 35% of the carotid implants remained patent. The biochemical properties of the Solcograft-P are better than those of Solcograft, its predecessor. The intimal lining was consistently smooth and homogeneous in grafts of biological origin, and no aneurysm was observed. Infection and early thrombosis occured no more frequently than with other grafts. The new Solcograft-P, crosslinked via ester and amide groups, seems to represent a real improvement over Solcograft. Our results suggest that Solcograft-P should prove valuable in various cases of reconstructive vascular surgery of the lower limb, especially when the autologous vena saphena magna is not available, and its mechanical properties may well prove suitable for both arterial and venous replacement.

  14. Preparation of laser micropore porcine acellular dermal matrix for skin graft: an experimental study.

    Science.gov (United States)

    Chai, Jia-Ke; Liang, Li-Ming; Yang, Hong-Ming; Feng, Rui; Yin, Hui-Nan; Li, Feng-Yu; Sheng, Zhi-Yong

    2007-09-01

    In our previous study, we used composite grafts consisting of meshed porcine acellular dermal matrix (PADM) and thin split-thickness autologous epidermis to cover full thickness burn wounds in clinical practice. However, a certain degree of contraction might occur because the distribution of dermal matrix was not uniform in burn wound. In this study, we prepare a composite skin graft consisting of PADM with the aid of laser to improve the quality of healing of burn wound. PADM was prepared by the trypsin/Triton X-100 method. Micropores were produced on the PADM with a laser punch. The distance between micropores varied from 0.8, 1.0, 1.2 to 1.5mm. Full thickness defect wounds were created on the back of 144 SD rats. The rats were randomly divided into six groups: micropore groups I-IV in which the wound were grafted with PADM with micropores, in four different distances, respectively and split-thickness autograft; mesh group rats received meshed PADM graft and split-thickness autograft; control group received simple split-thickness autografting. The status of wound healing was histologically observed at regular time points after surgery. The wound healing rate and contraction rate were calculated. The wound healing rate in micropore groups I and II was not statistically different from that in control group, but was significantly higher than that in mesh group 6 weeks after grafting. The wound healing rate in micropore groups III and IV was lower than that in mesh and control groups 4 and 6 weeks after grafting. The wound contraction rate in micropore groups I and II was remarkably lower than that in control group 4 and 6 weeks after surgery and it was significantly much lower than that in mesh group 6 weeks after surgery. Histological examination revealed good epithelization, regularly arranged collagenous fibers and integral structure of basement membrane. Laser micropore PADM (0.8 or 1.0mm in distance) grafting in combination with split-thickness autografting can

  15. Graft survival and cytokine production profile after limbal transplantation in the experimental mouse model

    Czech Academy of Sciences Publication Activity Database

    Lenčová, Anna; Pokorná, Kateřina; Zajícová, Alena; Krulová, Magdalena; Filipec, M.; Holáň, Vladimír

    2011-01-01

    Roč. 24, č. 3 (2011), s. 189-194 ISSN 0966-3274 R&D Projects: GA AV ČR KAN200520804; GA MŠk 1M0506; GA ČR GD310/08/H077 Institutional research plan: CEZ:AV0Z50520514 Keywords : limbal transplantation * graft survival * cytokine response Subject RIV: EC - Immunology Impact factor: 1.459, year: 2011

  16. Laxity of the elbow after experimental excision of the radial head and division of the medial collateral ligament. Efficacy of ligament repair and radial head prosthetic replacement

    DEFF Research Database (Denmark)

    Jensen, S.L.; Deutch, S.R.; Olsen, B.S.

    2003-01-01

    We studied the stabilising effect of prosthetic replacement of the radial head and repair of the medial collateral ligament (MCL) after excision of the radial head and section of the MCL in five cadaver elbows. Division of the MCL increased valgus angulation (mean 3.9 +/- 1.5 degrees) and internal...

  17. GIANT PROSTHETIC VALVE THROMBUS

    Directory of Open Access Journals (Sweden)

    Prashanth Kumar

    2015-04-01

    Full Text Available Mechanical prosthetic valves are predisposed to bleeding, thrombosis & thromboembolic complications. Overall incidence of thromboembolic complications is 1% per year who are on oral anticoagulants, whereas bleeding complications incidence is 0.5% to 6.6% per year. 1, 2 Minimization of Scylla of thromboembolic & Charybdis of bleeding complication needs a balancing act of optimal antithrombotic therapy. We are reporting a case of middle aged male patient with prosthetic mitral valve presenting in heart failure. Patient had discontinued anticoagulants, as he had subdural hematoma in the past. He presented to our institute with a giant prosthetic valve thrombus.

  18. Chest wall reconstruction with autologas rib grafts in dogs and report of a clinic case.

    Science.gov (United States)

    Tunçözgür, B; Elbeyli, L; Güngör, A; Işik, F; Akay, H

    1999-09-01

    Nowadays, in chest wall reconstruction prosthetic materials are generally used. However, the rejections of prosthetic materials and infections frequently occur in chest wall reconstruction, especially after radiotherapy or resection that is performed due to infections. We used 10 mongrel dogs and performed resections of 8 cm diameter on their chest walls. In the reconstruction of these defects, in five of the subjects, we used two free rib grafts with periosteum to be resected from the contralateral side and in other five subjects, we used free rib grafts without periosteum. After this experimental study, sternal resection was performed in a 24-year-old man because of sternal osteomyelitis. First to obtain rib grafts with periosteum, partial resection was performed to 5th, 7th, and 9th ribs of the lateral left side. After, total sternal resection, end to end anastomosis was performed to the 2nd, 3rd, 4th and 5th anterior ends of the ribs. Autogeneous rib grafts were found to be enough to provide chest wall stabilization. The contralateral autogeneous free rib grafts can successfully be used in reconstruction of wide chest wall defects. This method is found to be effective and sufficient to prevent infection, rejection and to provide stabilization.

  19. Experimental high-frequency ultrasound can detect graft rejection after small bowel transplantation.

    Science.gov (United States)

    Yang, R; Liu, Q; Wu, E X; Pescovitz, M D; Collins, M H; Kopecky, K K; Grosfeld, J L

    1994-02-01

    Early diagnosis of graft rejection after small bowel transplantation (SBT) can allow prompt institution of vigorous immunosuppressive therapy, with resultant reversal of the rejection process. The current method for graft monitoring is random mucosal biopsy from a stomal site or through an endoscope. However, because early rejection often has a patchy distribution, it could be missed by random biopsy. We hypothesized that the pathological process of rejection would alter acoustic impedance of the tissue and thus change the ultrasonic patterns of the graft intestinal wall. If this hypothesis is correct, then high-frequency endoscopic ultrasound (US) could be used to monitor the entire transplanted bowel and guide the biopsy, with improved yields. This hypothesis was tested in a rat orthotopic SBT model. Sixty-two intestinal specimens (9 isografts, 12 allografts treated with cyclosporine A [CsA], 22 untreated allografts, and 19 intestines from normal rats) were collected for in vitro transluminal US imaging (30 MHz) and histopathologic study. The echo pattern of normal rat intestinal wall consisted of five echo layers that correlated spatially with the histological layers: the innermost hyperechoic layer 1, plus hypoechoic layer 2, corresponded to the mucosa; hyperechoic layer 3, the submucosa; anechoic layer 4, the muscularis propria; and hyperechoic layer 5, the serosa. The isografts and CsA-treated allografts were identical histologically and ultrasonically to normal intestine. However, the echo patterns of the untreated allografts had progressive loss of architectural stratification, with worsening rejection. The change began with patchy indistinctness and disruption of hyperechoic layers 1, 3 and 5, and progressed to total obliteration of the layers, with the intestinal wall becoming a nonstratified hypoechoic structure.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Experimental study of vascularized nerve graft: evaluation of nerve regeneration using choline acetyltransferase activity.

    Science.gov (United States)

    Iwai, M; Tamai, S; Yajima, H; Kawanishi, K

    2001-01-01

    A comparative study of nerve regeneration was performed on vascularized nerve graft (VNG) and free nerve graft (FNG) in Fischer strain rats. A segment of the sciatic nerve with vascular pedicle of the femoral artery and vein was harvested from syngeneic donor rat for the VNG group and the sciatic nerve in the same length without vascular pedicle was harvested for the FNG group. They were transplanted to a nerve defect in the sciatic nerve of syngeneic recipient rats. At 2, 4, 6, 8, 12, 16, and 24 weeks after operation, the sciatic nerves were biopsied and processed for evaluation of choline acetyltransferase (CAT) activity, histological studies, and measurement of wet weight of the muscle innervated by the sciatic nerve. Electrophysiological evaluation of the grafted nerve was also performed before sacrifice. The average CAT activity in the distal to the distal suture site was 383 cpm in VNG and 361 cpm in FNG at 2 weeks; 6,189 cpm in VNG and 2,264 cpm in FNG at 4 weeks; and 11,299 cpm in VNG and 9,424 cpm in FNG at 6 weeks postoperatively. The value of the VNG group was statistically higher than that of the FNG group at 4 weeks postoperatively. Electrophysiological and histological findings also suggested that nerve regeneration in the VNG group was superior to that in the FNG group during the same period. However, there was no significant difference between the two groups after 6 weeks postoperatively in any of the evaluations. The CAT measurement was useful in the experiments, because it was highly sensitive and reproducible. Copyright 2001 Wiley-Liss, Inc.

  1. Rehabilitation and Prosthetic Services

    Science.gov (United States)

    ... Review Resources AT Education Blind Rehab Chiropractic Service Polytrauma/TBI Prosthetics & Sensory Aids Recreation Therapy More Health ... Military Sexual Trauma PTSD Research (MIRECC) Military Exposures Polytrauma Rehabilitation Spinal Cord Injury Telehealth Womens Health Issues ...

  2. Prosthetics / Limb Loss

    Science.gov (United States)

    ... implant to encourage the sealing process. Implanting titanium prosthetic components avoids the need for a socket. But preventing bacterial invasion and infection is a key challenge, one that this research ...

  3. Prosthetic Joint Infections

    Science.gov (United States)

    Aslam, Saima; Darouiche, Rabih O.

    2012-01-01

    Prosthetic joint infections represent a major therapeutic challenge for both healthcare providers and patients. This paper reviews the predisposing factors, pathogenesis, microbiology, diagnosis, treatment and prophylaxis of prosthetic joint infection. The most optimal management strategy should be identified based on a number of considerations including type and duration of infection, antimicrobial susceptibility of the infecting pathogen, condition of infected tissues and bone stock, patient wishes and functional status. PMID:22847032

  4. Observations on human smooth muscle cell cultures from hyperplastic lesions of prosthetic bypass grafts: Production of a platelet-derived growth factor-like mitogen and expression of a gene for a platelet-derived growth factor receptor--a preliminary study

    International Nuclear Information System (INIS)

    Birinyi, L.K.; Warner, S.J.; Salomon, R.N.; Callow, A.D.; Libby, P.

    1989-01-01

    Prosthetic bypass grafts placed to the distal lower extremity often fail because of an occlusive tissue response in the perianastomotic region. The origin of the cells that comprise this occlusive lesion and the causes of the cellular proliferation are not known. To increase our understanding of this process we cultured cells from hyperplastic lesions obtained from patients at the time of reexploration for lower extremity graft failure, and we studied their identity and growth factor production in tissue culture. These cultures contain cells that express muscle-specific actin isoforms, shown by immunohistochemical staining, consistent with vascular smooth muscle origin. These cultures also released material that stimulated smooth muscle cell growth. A portion of this activity was similar to platelet-derived growth factor, since preincubation with antibody-to-human platelet-derived growth factor partially blocked the mitogenic effect of medium conditioned by human anastomotic hyperplastic cells. These conditioned media also contained material that competed with platelet-derived growth factor for its receptor, as measured in a radioreceptor assay. Northern blot analysis showed that these cells contain messenger RNA that encodes the A chain but not the B chain of platelet-derived growth factor. In addition, these cells contain messenger RNA that encodes a platelet-derived growth factor receptor. We conclude that cultured smooth muscle cells from human anastomotic hyperplastic lesions express genes for platelet-derived growth factor A chain and a platelet-derived growth factor receptor and secrete biologically active molecules similar to platelet-derived growth factor

  5. Prosthetic replacement of the infrahepatic inferior vena cava for leiomyosarcoma.

    Science.gov (United States)

    Illuminati, Giulio; Calio', Francesco G; D'Urso, Antonio; Giacobbi, Daniela; Papaspyropoulos, Vassilios; Ceccanei, Gianluca

    2006-09-01

    Resection of the infrahepatic inferior vena cava associated with prosthetic graft replacement for caval leiomyosarcoma is an acceptable procedure to obtain prolonged and good-quality survival. A consecutive sample clinical study with a mean follow-up of 40 months. The surgical department of an academic tertiary center and an affiliated secondary care center. Eleven patients, with a mean age of 51 years, who have primary leiomyosarcoma of the infrahepatic inferior vena cava. All of the patients underwent radical resection of the tumor en bloc with the affected segment of the vena cava. Reconstruction consisted of 10 cavocaval polytetrafluoroethylene grafts and 1 cavobiliac graft. An associated right nephrectomy was performed in 2 cases. The left renal vein was reimplanted in the graft in 3 cases. Cumulative disease-specific survival, disease-free survival, and graft patency rates expressed by standard life-table analysis. No patients died in the postoperative period. The cumulative (SE) disease-specific survival rate was 53% (21%) at 5 years. The cumulative (SE) disease-free survival rate was 44% (19%) at 5 years. The cumulative (SE) graft patency rate was 67% (22%) at 5 years. Radical resection followed by prosthetic graft reconstruction is a valuable method for treating primary leiomyosarcoma of the infrahepatic inferior vena cava.

  6. Skin graft

    Science.gov (United States)

    Skin transplant; Skin autografting; FTSG; STSG; Split thickness skin graft; Full thickness skin graft ... donor site. Most people who are having a skin graft have a split-thickness skin graft. This takes ...

  7. The Prosthetic Experience Between Body and Technology

    DEFF Research Database (Denmark)

    Søndergaard, Morten

    2018-01-01

    In this paper, I argue that a prosthetic aesthetic instigated by experimental art practices operate with and within a ‘second nature’ – in-between science and art. Drawing on theories from Dewey and Edelman and examples from Da Vinci, Brancusi, Man Ray, Dali and Stelarc, I am calling...

  8. Graft copolymerization of acrylic acid to cassava starch-Evaluation of the influences of process parameters by an experimental design method

    NARCIS (Netherlands)

    Witono, J. R.; Noordergraaf, I. W.; Heeres, H. J.; Janssen, L. P. B. M.

    2012-01-01

    The graft copolymerization of cassava starch with acrylic acid was investigated using a free radical initiator system (Fe2+/H2O2 redox system) in water. A comprehensive understanding of the important variables and their interaction has been obtained by applying an experimental design method. In this

  9. Biomechanical and histologic comparison of Achilles tendon ruptures reinforced with intratendinous and peritendinous plantaris tendon grafts in rabbits: an experimental study.

    Science.gov (United States)

    Ilhami, Kuru; Gokhan, Maralcan; Ulukan, Inan; Eray, Bozan M; Levent, Altinel; Ciğdem, Tokyol

    2004-11-01

    We hypothesized that the closer the reinforcing graft was to the repair zone, the more strength the healed tendon would achieved. Therefore, we compared the ruptured rabbit Achilles tendons reinforced with intratendinous and peritendinous plantaris grafts. The experimental study was performed on Achilles tendons of 20 rabbits. First, they were divided into two groups: group I (n=10) underwent intratendinous graft and end-to-end tenorraphy, and group P (n=10) were repaired end-to-end and then reinforced with a peritendinous plantaris graft. An above-knee cast was applied during 6 weeks postoperatively. The two groups were compared to each other biomechanically and histologically. Seven randomly selected rabbits from each group were used for biomechanical evaluation. The remaining six rabbits (three from each group) were used for histologic comparison. Non-operated sides (n=20) served as the control group. The mean maximum load at rupture of the repaired and control groups was 159.9+/-31 N, 83+/-7.5 N, and 207.5+/-35 N for group I, group P, and the control group, respectively. Values between groups were significantly different considering maximum load and absorbed energy to rupture. There was no significant difference between groups I and P in respect to strain. Control group tendons (groups I-C and P-C) had significantly more lengthening capability than operated tendons. Macroscopically, group I tendons were thicker and stiffer than group P tendons. Histologically, differences between the group I and group P specimens revealed that the healing process was faster in tendons augmented intratendinously. In reinforcing Achilles tendon repair, the site of the tendon graft affected the result. When the graft was used intratendinously, the healed tendon was more similar biomechanically to normal tendon and had more graft-tendon orientation histologically than the tendon augmented peritendinously.

  10. Gonococcal Prosthetic Joint Infection.

    Science.gov (United States)

    Gassiep, Ian; Gilpin, Bradley; Douglas, Joel; Siebert, David

    2017-01-01

    Neisseria gonorrhoea is a common sexually transmitted infection worldwide. Disseminated gonococcal infection is an infrequent presentation and rarely can be associated with septic arthritis. Incidence of this infection is rising, both internationally and in older age groups. We present the first documented case of N. gonorrhoea prosthetic joint infection which was successfully treated with laparoscopic debridement and antimicrobial therapy.

  11. Amputation and Prosthetics

    Science.gov (United States)

    ... All Topics A-Z Videos Infographics Symptom Picker Anatomy Bones Joints Muscles Nerves Vessels Tendons About Hand Surgery What is a Hand Surgeon? What is a Hand Therapist? Media Find a Hand Surgeon Home Anatomy Amputation and Prosthetics Email to a friend * required ...

  12. A new procedure for processing extracted teeth for immediate grafting in post-extraction sockets. An experimental study in American Fox Hound dogs.

    Science.gov (United States)

    Calvo-Guirado, José Luis; Cegarra Del Pino, Pilar; Sapoznikov, Lari; Delgado Ruiz, Rafael Arcesio; Fernández-Domínguez, Manuel; Gehrke, Sérgio Alexandre

    2018-05-01

    To investigate freshly extracted dental particulate used to graft post-extraction sockets in dogs, comparing new bone formation at experimental and control sites. Bilateral premolars P2, P3, P4 and first mandibular molars were extracted atraumatically from six American Fox Hound dogs. The teeth were ground immediately using a 'Smart Dentin Grinder'. The dentin particulate was sieved to ensure a grain size of 300-1200μm and immersed in an alcohol cleanser to dissolve organic debris and bacteria, followed by washing in sterile saline buffer solution. The animals were divided into two groups randomly: group 'A' (control) samples were left to heal without any extraction socket grafting procedure; group 'B' (experimental) sockets were filled with the autogenous dentin particulate graft. The rate of tissue healing and the quantity of bone formation were evaluated using histological and histomorphometric analyses at 60 and 90 days post-grafting. The type of bone generated was categorized as woven (immature bone) or lamellar bone (mature bone). Substantially more bone formation was found in Group B (experimental) than Group A (control) at 60 and 90 days (psocket preservation, protecting both buccal and lingual plates, generating large amounts of new woven bone formation after 60 days, and small amounts of lamellar bone after 90 days healing. Copyright © 2018 Elsevier GmbH. All rights reserved.

  13. Histological comparison of autograft, allograft-DBM, xenograft, and synthetic grafts in a trabecular bone defect: an experimental study in rabbits.

    Science.gov (United States)

    Athanasiou, Vasilis T; Papachristou, Dionysios J; Panagopoulos, Andreas; Saridis, Alkis; Scopa, Chrisoula D; Megas, Panagiotis

    2010-01-01

    Different types of bone-graft substitutes have been developed and are on the market worldwide to eliminate the drawbacks of autogenous grafting. This experimental animal study was undertaken to evaluate the different histological properties of various bone graft substitutes utilized in this hospital. Ninety New Zealand white rabbits were divided into six groups of 15 animals. Under general anesthesia, a 4.5 mm-wide hole was drilled into both the lateral femoral condyles of each rabbit, for a total of 180 condyles for analysis. The bone defects were filled with various grafts, these being 1) autograft, 2) DBM crunch allograft (Grafton), 3) bovine cancellous bone xenograft (Lubboc), 4) calcium phosphate hydroxyapatite substitute (Ceraform), 5) calcium sulfate substitute (Osteoset), and 6) no filling (control). The animals were sacrificed at 1, 3, and 6 months after implantation and tissue samples from the implanted areas were processed for histological evaluation. A histological grading scale was designed to determine the different histological parameters of bone healing. The highest histological grades were achieved with the use of cancellous bone autograft. Bovine xenograft (Lubboc) was the second best in the histological scale grading. The other substitutes (Grafton, Ceraform, Osteoset) had similar scores but were inferior to both allograft and xenograft. Bovine xenograft showed better biological response than the other bone graft substitutes; however, more clinical studies are necessary to determine its overall effectiveness.

  14. Dilatation of aortic grafts over time: what to expect and when to be concerned

    DEFF Research Database (Denmark)

    Schroeder, Torben V; Eldrup, Nikolaj; Just, Sven

    2009-01-01

    Dilatation of aortic prosthetic grafts is commonly reported, but most reports are anecdotal, with little objective data in the literature. We performed a prospective trial of 303 patients who underwent prosthetic graft repair for aortic aneurysm or occlusive disease, randomizing patients between...... insertion of a woven polyester or expanded polytetrafluoroethylene (ePTFE) graft. Patients were followed with computed tomography and ultrasonography for up to 5 years in order to assess the frequency and magnitude of postoperative dilatation. Graft dilatation was documented in patients with polyester...... grafts at 12 months. Thereafter and up to 60 months, polyester grafts did not dilate further. After 5 years, polyester prostheses had dilated by 25% and ePTFE by 12.5%, as determined by computed tomography imaging. These observations suggest that dilatation of prosthetic grafts is more frequent...

  15. An experimental study on inhibiting graft rejection following high-risk penetrating keratoplasty by CD25 siRNA nanocarrier in rats

    Directory of Open Access Journals (Sweden)

    Yun-jie SHI

    2015-06-01

    RNA in the experimental group was significantly lower at every single time points. Conclusions CD25siRNA gene transfer could successfully down-regulate CD25 expression, inhibit graft rejection and prolong the survival time of allogeneic corneal graft. DOI: 10.11855/j.issn.0577-7402.2015.04.09

  16. Protection of intestinal anastomoses in septic environment with peritoneal graft and polyglycolic acid mesh: an experimental study.

    Science.gov (United States)

    Dilek, O N; Bakir, B; Dilek, F H; Demirel, H; Yiğit, M F

    1996-01-01

    We carried out an experimental study in dogs to evaluate the outcome of large bowel anastomosis with 6 stitches (Group C, n : 6) in a septic environment with protection by a polyglycolic acid (PGA) mesh (Group M, n : 12) or peritoneal graft (Group P, n : 12). Thirty dogs were used to compare the techniques. Two dogs in each group were re-operated after 3, 5, 7, 14, 28 and 90 days. They were evaluated for adhesion formation, lumen diameter (anastomotic index), clinical features, histologic appearance and quality of healing at the anastomotic sites. All dogs in group P and group M survived, whereas 2 dogs in the control group died of anastomotic leakage and 3 dogs were re-operated for anastomotic leakage and peritonitis. In group M, one dog was reoperated because of the anastomotic leakage and two dogs were reoperated because of the anastomotic stenosis. Also, 4 anastomoses showed evidence of moderate stenosis. In group P, three anastomoses were graded as minimal stenosis. Histopathologic evaluation showed more complete epithelization, less inflammation, and less adhesion in group P than group M. We could not find any study in the literature that described and compared both techniques. We report here the results of such a study.

  17. Prosthetics in Paediatric Dentistry

    Directory of Open Access Journals (Sweden)

    Vulićević Zoran

    2017-07-01

    Full Text Available Premature loss of teeth in children may lead to both functional and esthetic problems. Missing teeth in both anterior and posterior regions may cause malfunctions in mastication and proper pronunciation. If the missing teeth are not replaced, further complications may occur, including adjacent tooth migration, loss of alveolar bone, and irregular occlusion. Considering the sensitive nature of children, loss of teeth may cause the development of insecurities and low self esteem problems. Due to dynamic nature of growth in children and adolescents, prosthetic appliances must not hinder development of orofacial system, and must meet adequate esthetic and functional standards. Dental prosthetic appliances in paediatrics must be planned with respect to the special conditions that led to tooth loss or damage. Multi-disciplinary approach is needed, under constant supervision of paediatric dentist and orthodontist, as well as regular checkups with clinical and radiographical examinations.

  18. Welding of Prosthetic Alloys

    Directory of Open Access Journals (Sweden)

    Wojciechowska M.

    2015-04-01

    Full Text Available This paper presents the techniques of joining metal denture elements, used in prosthetic dentistry: the traditional soldering technique with a gas burner and a new technique of welding with a laser beam; the aim of the study was to make a comparative assessment of the quality of the joints in view of the possibility of applying them in prosthetic structures. Fractographic examinations were conducted along with tensile strength and impact strength tests, and the quality of the joints was assessed compared to the solid metal. The experiments have shown that the metal elements used to make dentures, joined by the technique which employs a laser beam, have better strength properties than those achieved with a gas burner.

  19. Topical application of sodium hyaluronate for preventing perivascular adhesion of the vein grafts in rabbits: An experimental study

    Directory of Open Access Journals (Sweden)

    Ming-ke GUO

    2017-10-01

    Full Text Available Objective To explore the effect of topical application of sodium hyaluronate on preventing perivascular adhesion of the vein grafts in rabbits. Methods Thirty-six male New Zealand white rabbits, aged 5 months, were randomly and equally divided into 2 groups: groups A and B. Arterial defect model was established by cutting about 1cm artery from the middle part of the dissected left common carotid artery. A section about 3cm was cut from the right external jugular vein, and the harvested vein was inverted and anastomosed end-to-end to the artery defect. After the anastomosis, the adventitia and two anastomoses of the grafted veins in group A were coated locally with 0.2ml sodium hyaluronate. The grafted veins were obtained 1, 2 and 4 weeks after the operation, with the perivascular adhesion of the vein grafts being examined macroscopically before the resection. HE staining and Masson staining were preformed for histological changes of grafted vein wall and the perivascular adhesion of the vein grafts. At 2, 4 weeks postoperation, the perivascular adhesions of the vein grafts were graded by the grading criteria of adhesion in macroscopic evaluation and histological evaluation. Results At 1, 2 and 4 weeks postoperatively, the macroscopic and histological observation found that the perivascular adhesions in group A were looser than those in group B. The macroscopic grade and histological grade were lower in group A than in group B, there was a significant difference between the two groups at 2 and 4 weeks postoperation (P<0.05. Conclusion Topical application of sodium hyaluronate can reduce the perivascular adhesion and is an ideal treatment strategy for preventing perivascular adhesion of vein grafts. DOI: 10.11855/j.issn.0577-7402.2017.08.14

  20. An Evaluation of Dental Prosthetic Status and Prosthetic Needs ...

    African Journals Online (AJOL)

    present cross‑sectional study aimed to evaluate the dental prosthetic status and prosthetic needs among eunuchs .... who consented to become part of the study guided us to the .... to the reason that our study population comprised of adults with low SES. ... Arora M, Schwarz E, Sivaneswaran S, Banks E. Cigarette smoking.

  1. Anaerobic prosthetic joint infection.

    Science.gov (United States)

    Shah, Neel B; Tande, Aaron J; Patel, Robin; Berbari, Elie F

    2015-12-01

    In an effort to improve mobility and alleviate pain from degenerative and connective tissue joint disease, an increasing number of individuals are undergoing prosthetic joint replacement in the United States. Joint replacement is a highly effective intervention, resulting in improved quality of life and increased independence [1]. By 2030, it is predicted that approximately 4 million total hip and knee arthroplasties will be performed yearly in the United States [2]. One of the major complications associated with this procedure is prosthetic joint infection (PJI), occurring at a rate of 1-2% [3-7]. In 2011, the Musculoskeletal Infectious Society created a unifying definition for prosthetic joint infection [8]. The following year, the Infectious Disease Society of America published practice guidelines that focused on the diagnosis and management of PJI. These guidelines focused on the management of commonly encountered organisms associated with PJI, including staphylococci, streptococci and select aerobic Gram-negative bacteria. However, with the exception of Propionibacterium acnes, management of other anaerobic organisms was not addressed in these guidelines [1]. Although making up approximately 3-6% of PJI [9,10], anaerobic microorganisms cause devastating complications, and similar to the more common organisms associated with PJI, these bacteria also result in significant morbidity, poor outcomes and increased health-care costs. Data on diagnosis and management of anaerobic PJI is mostly derived from case reports, along with a few cohort studies [3]. There is a paucity of published data outlining factors associated with risks, diagnosis and management of anaerobic PJI. We therefore reviewed available literature on anaerobic PJI by systematically searching the PubMed database, and collected data from secondary searches to determine information on pathogenesis, demographic data, clinical features, diagnosis and management. We focused our search on five commonly

  2. Prosthetic Joint Infection

    Science.gov (United States)

    Tande, Aaron J.

    2014-01-01

    SUMMARY Prosthetic joint infection (PJI) is a tremendous burden for individual patients as well as the global health care industry. While a small minority of joint arthroplasties will become infected, appropriate recognition and management are critical to preserve or restore adequate function and prevent excess morbidity. In this review, we describe the reported risk factors for and clinical manifestations of PJI. We discuss the pathogenesis of PJI and the numerous microorganisms that can cause this devastating infection. The recently proposed consensus definitions of PJI and approaches to accurate diagnosis are reviewed in detail. An overview of the treatment and prevention of this challenging condition is provided. PMID:24696437

  3. Guide to prosthetic cardiac valves

    International Nuclear Information System (INIS)

    Morse, D.; Steiner, R.M.; Fernandez, J.

    1985-01-01

    This book contains 10 chapters. Some of the chapter titles are: The development of artificial heart valves: Introduction and historical perspective; The radiology of prosthetic heart valves; The evaluation of patients for prosthetic valve implantation; Pathology of cardiac valve replacement; and Bioengineering of mechanical and biological heart valve substitutes

  4. Reconstruction of mandibular defects after radiation, using a free, living bone, graft transferred by microvascular anastomoses. An experimental study

    International Nuclear Information System (INIS)

    Ostrup, L.T.; Fredrickson, J.M.

    1975-01-01

    The replacement of a mandibular defect by a free, composite rib graft, transferred by microvascular anastomoses of the posterior intercostal vessels to donor vessels in the neck was described previously. We now present data which demonstrate that successful results can be achieved even after radical mandibular radiation. This technique, done in dogs, has obvious implications in the management of oral cancer in man

  5. Transplantation and microsurgical anastomosis of free omental grafts: experimental animal model of a new operative technique in dogs.

    Science.gov (United States)

    Pap-Szekeres, Jozsef; Cserni, Gabor; Furka, Istvan; Svebis, Mihaly; Cserni, Tamas; Brath, Endre; Nemeth, Norbert; Miko, Iren

    2003-01-01

    Our objective was the elaboration of a new animal model for the free transplantation of an omental flap and the examination of its viability in dogs. The cooled omental flap from the abdomen was freely transplanted to the lateral cervical region, and its blood supply was established with microsurgical anastomoses. The technique was developed in 5 dogs, and short-term survival examinations were later carried out in 3 cases by means of this method. Postoperative viability was assessed by angiography, methylene blue testing, and histology. Of the 3 transplanted grafts, 2 still survived 1 week after the operation. For technical reasons, 1 flap thrombotized. For determination of the viability of the transplanted graft, histology proved best. Vital reactions, including granulation tissue and angiogenesis, were present on the histological slides. The short-term survival of an omental flap can be ensured with microsurgical transplantation in dogs. Copyright 2003 Wiley-Liss, Inc.

  6. Management of Prosthetic Joint Infection.

    Science.gov (United States)

    Tande, Aaron J; Gomez-Urena, Eric O; Berbari, Elie F; Osmon, Douglas R

    2017-06-01

    Although uncommon, prosthetic joint infection is a devastating complication. This challenging condition requires a coordinated management approach to achieve good patient outcomes. This review details the general principles to consider when managing patients with prosthetic joint infection. The different medical/surgical treatment strategies and how to appropriately select a strategy are discussed. The data to support each strategy are presented, along with discussion of antimicrobial strategies in specific situations. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Advanced Prosthetic Gait Training Tool

    Science.gov (United States)

    2015-12-01

    modules to train individuals to distinguish gait deviations (trunk motion and lower-limb motion). Each of these modules help trainers improve their...AWARD NUMBER: W81XWH-10-1-0870 TITLE: Advanced Prosthetic Gait Training Tool PRINCIPAL INVESTIGATOR: Dr. Karim Abdel-Malek CONTRACTING...study is to produce a computer-based Advanced Prosthetic Gait Training Tool to aid in the training of clinicians at military treatment facilities

  8. Which prosthetic foot to prescribe?

    OpenAIRE

    De Asha, AR; Barnett, CT; Struchkov, V; Buckley, JG

    2017-01-01

    Introduction: \\ud Clinicians typically use findings from cohort studies to objectively inform judgements regarding the potential (dis)advantages of prescribing a new prosthetic device. However, before finalising prescription a clinician will typically ask a patient to 'try out' a change of prosthetic device while the patient is at the clinic. Observed differences in gait when using the new device should be the result of the device’s mechanical function, but could also conceivably be due to pa...

  9. Pre-prosthetic surgery: Mandible

    Directory of Open Access Journals (Sweden)

    Veeramalai Naidu Devaki

    2012-01-01

    Full Text Available Pre-prosthetic surgery is that part of oral and maxillofacial surgery which restores oral function and facial form. This is concerned with surgical modification of the alveolar process and its surrounding structures to enable the fabrication of a well-fitting, comfortable, and esthetic dental prosthesis. The ultimate goal of pre-prosthetic surgery is to prepare a mouth to receive a dental prosthesis by redesigning and smoothening bony edges.

  10. Experimental Evaluation of the Effectiveness of Demineralized Bone Matrix and Collagenated Heterologous Bone Grafts Used Alone or in Combination with Platelet-Rich Fibrin on Bone Healing in Sinus Floor Augmentation.

    Science.gov (United States)

    Peker, Elif; Karaca, Inci Rana; Yildirim, Benay

    2016-01-01

    The aim of this study was an experimental evaluation of the effectiveness of demineralized bone matrix (DBM) and collagenated heterologous bone graft (CHBG) used alone or in combination with platelet-rich fibrin on bone healing in sinus floor augmentation procedures. In this study, 36 New Zealand rabbits were used. The bilateral sinus elevation was performed, and 72 defects were obtained. The rabbit maxillary sinuses were divided into four groups according to the augmentation biomaterials obtained: demineralized bone matrix (Grafton DBM Putty, Osteotech; DBM group), DBM combined with platelet-rich fibrin (PRF; DBM + PRF group), collagenated heterologous bone graft (CHBG; Apatos Mix, OsteoBiol, Tecnoss; CHBG group), CHBG combined with PRF (CHBG + PRF group). All groups were sacrificed at 2, 4, and 8 weeks after surgery for histologic, histomorphometric, and immunohistochemical analyses. The inflammatory reaction was moderate to intense at the second week in all groups and declined from 2 to 8 weeks. New bone formation was started at the second week and increased from 2 to 8 weeks in all groups. There was no significant difference in bone formation between the experimental groups that used PRF mixed graft material and control groups that used only graft material. The percentage of new bone formation showed a significant difference in DBM groups and DBM + PRF groups compared with other groups. There were osteoclasts around all the bone graft materials used, but the percentage of residual graft particles was significantly higher in CHBG groups and CHBG + PRF groups at the eighth week. There is no beneficial effect of the application of PRF in combination with demineralized bone matrix or collagenated heterologous bone graft on bone formation in sinus floor augmentation. The results of this study showed that both collagenated heterologous bone graft and demineralized bone matrix have osteoconductive properties, but demineralized bone matrix showed more bone formation

  11. Skin Graft

    OpenAIRE

    Shimizu, Ruka; Kishi, Kazuo

    2012-01-01

    Skin graft is one of the most indispensable techniques in plastic surgery and dermatology. Skin grafts are used in a variety of clinical situations, such as traumatic wounds, defects after oncologic resection, burn reconstruction, scar contracture release, congenital skin deficiencies, hair restoration, vitiligo, and nipple-areola reconstruction. Skin grafts are generally avoided in the management of more complex wounds. Conditions with deep spaces and exposed bones normally require the use o...

  12. 100 top-cited scientific papers in limb prosthetics.

    Science.gov (United States)

    Eshraghi, Arezoo; Osman, Noor Azuan Abu; Gholizadeh, Hossein; Ali, Sadeeq; Shadgan, Babak

    2013-11-17

    Research has tremendously contributed to the developments in both practical and fundamental aspects of limb prosthetics. These advancements are reflected in scientific articles, particularly in the most cited papers. This article aimed to identify the 100 top-cited articles in the field of limb prosthetics and to investigate their main characteristics. Articles related to the field of limb prosthetics and published in the Web of Knowledge database of the Institute for Scientific Information (ISI) from the period of 1980 to 2012. The 100 most cited articles in limb prosthetics were selected based on the citation index report. All types of articles except for proceedings and letters were included in the study. The study design and level of evidence were determined using Sackett's initial rules of evidence. The level of evidence was categorized either as a systematic review or meta-analysis, randomized controlled trial, cohort study, case-control study, case series, expert opinion, or design and development. The top cited articles in prosthetics were published from 1980 to 2012 with a citation range of 11 to 90 times since publication. The mean citation rate was 24.43 (SD 16.7) times. Eighty-four percent of the articles were original publications and were most commonly prospective (76%) and case series studies (67%) that used human subjects (96%) providing level 4 evidence. Among the various fields, rehabilitation (47%), orthopedics (29%), and sport sciences (28%) were the most common fields of study. The study established that studies conducted in North America and were written in English had the highest citations. Top cited articles primarily dealt with lower limb prosthetics, specifically, on transtibial and transradial prosthetic limbs. Majority of the articles were experimental studies.

  13. Systemic thioridazine in combination with dicloxacillin against early aortic graft infections caused by Staphylococcus aureus in a porcine model

    DEFF Research Database (Denmark)

    Stenger, Michael; Behr-Rasmussen, Carsten; Klein, Kasper

    2017-01-01

    INTRODUCTION: Conservative treatment solutions against aortic prosthetic vascular graft infection (APVGI) for inoperable patients are limited. The combination of antibiotics with antibacterial helper compounds, such as the neuroleptic drug thioridazine (TDZ), should be explored. AIM: To investigate...

  14. Evaluation of healing potential of autogenous, macroscopic fat deposited or fat free, omental graft in experimental radius bone defect in rabbit: Radiological study

    International Nuclear Information System (INIS)

    Masouleh, M.N.; Haghdoost, I.S.; Heydari, G.A.C.; Raissi, A.; Mohitmafi, S.

    2011-01-01

    This study was designed for evaluation of the difference between the ability of greater omentum graft with or without macroscopic fat deposition in acceleration of bone healing process. Adult female New Zealand white rabbits (n=15) were randomly divided into three equal groups. In groups A and B, the drilled hole on the left radius was filled by the omentum without and with macroscopic fat deposition, respectively while drilled hole on the right radius left intact for consideration as control. In group C, the drilled hole on the left and right radius was filled by the omentum sample with and without macroscopic fat deposition, respectively. Experimental bone defects on the radiuses were secured by the pieces of greater omentum, with or without macroscopic fat deposition, which obtained as an autogenous graft from each rabbit in accompany with control samples. Standardized serial radiography for evaluation of bone healing was performed and the difference in bone healing process in three groups of study was determined. According to the obtained data, the radius bones which filled by omentum without macroscopic fat deposition showed faster healing process than the radius bones which filled by omentum with macroscopic fat deposition (P<0.05). (author)

  15. Bacterial adherence to vascular grafts after in vitro bacteremia

    International Nuclear Information System (INIS)

    Rosenman, J.E.; Pearce, W.H.; Kempczinski, R.F.

    1985-01-01

    All currently used arterial prosthetics have a greater susceptibility to infection following bacteremia than does autogenous tissue. This experiment compares quantitative bacterial adherence to various prosthetic materials after bacteremia carried out in a tightly controlled and quantitative fashion. Ten centimeters long, 4 mm i.d. Dacron, umbilical vein (HUV), and polytetrafluoroethylene (PTFE) grafts, as well as PTFE grafts with a running suture line at the midportion were tested. Each graft was interposed into a pulsatile perfusion system modified from a Waters MOX 100 TM renal transplant pump. Indium-111-labeled Staphylococcus aureus were added to heparinized canine blood to give a mean concentration of 4.7 X 10(6) bacteria/cc. This infected blood was recirculated through each graft for 30 min at a rate of 125 cc/m, 100 Torr (sys), 60 beats/min. The gamma counts/graft were used to calculate the number of bacteria/cm2 of graft surface. After nine experiments, a mean of 9.63 X 10(5) bacteria/cm2 were adherent to the Dacron, 1.04 X 10(5) bacteria/cm2 to the HUV, and 2.15 X 10(4) bacteria/cm2 to the PTFE. These differences were all significant at the 0.05 level. The addition of a suture line increased bacterial adherence to the PTFE graft by 50%. These results suggest that PTFE is the vascular graft material of choice when a prosthetic graft must be implanted despite a high risk of subsequent clinical bacteremia. An in vitro, pulsatile perfusion model gave accurate and reproducible results, and appears well suited for further studies of bacterial, or platelet adherence to grafts, as well as the biomechanics of vascular conduits

  16. Improving diagnostic accuracy in aortic prosthetic graft infection

    NARCIS (Netherlands)

    Saleem, Rani

    2017-01-01

    Vaatprothese infecties (VPI) komen relatief weinig voor, echter het klinisch beloop ervan kent hoge morbiditeit en mortaliteit. Derhalve worden bij de implantatie van vaatprotheses diverse preventieve maatregelen genomen om VPI te voorkomen. Ondanks preventieve maatregelen blijft prothesemateriaal

  17. Biomechanical properties of patellar and hamstring graft tibial fixation techniques in anterior cruciate ligament reconstruction: experimental study with roentgen stereometric analysis.

    Science.gov (United States)

    Adam, Frank; Pape, Dietrich; Schiel, Karin; Steimer, Oliver; Kohn, Dieter; Rupp, Stefan

    2004-01-01

    Reliable fixation of the soft hamstring grafts in ACL reconstruction has been reported as problematic. The biomechanical properties of patellar tendon (PT) grafts fixed with biodegradable screws (PTBS) are superior compared to quadrupled hamstring grafts fixed with BioScrew (HBS) or Suture-Disc fixation (HSD). Controlled laboratory study with roentgen stereometric analysis (RSA). Ten porcine specimens were prepared for each group. In the PT group, the bone plugs were fixed with a 7 x 25 mm BioScrew. In the hamstring group, four-stranded tendon grafts were anchored within a tibial tunnel of 8 mm diameter either with a 7 x 25 mm BioScrew or eight polyester sutures knotted over a Suture-Disc. The grafts were loaded stepwise, and micromotion of the graft inside the tibial tunnel was measured with RSA. Hamstring grafts failed at lower loads (HBS: 536 N, HSD 445 N) than the PTBS grafts (658 N). Stiffness in the PTBS group was much greater compared to the hamstring groups (3500 N/mm versus HBS = 517 N/mm and HSD = 111 N/mm). Irreversible graft motion after graft loading with 200 N was measured at 0.03 mm (PTBS), 0.38mm (HBS), and 1.85mm (HSD). Elasticity for the HSD fixation was measured at 0.67 mm at 100 N and 1.32 mm at 200 N load. Hamstring graft fixation with BioScrew and Suture-Disc displayed less stiffness and early graft motion compared to PTBS fixation. Screw fixation of tendon grafts is superior to Suture-Disc fixation with linkage material since it offers greater stiffness and less graft motion inside the tibial tunnel. Our results revealed graft motion for hamstring fixation with screw or linkage material at loads that occur during rehabilitation. This, in turn, may lead to graft laxity.

  18. Candida infection of a prosthetic shoulder joint

    Energy Technology Data Exchange (ETDEWEB)

    Lichtman, E.A.

    1983-09-01

    A heroin addict developed a Candida parapsilosis infection in a prosthetic shoulder joint. Radiographs showed loose fragments of cement with prosthetic loosening. The patient was treated with removal of the prosthesis and intravenous amphotericin B followed by oral ketoconazole.

  19. Candida infection of a prosthetic shoulder joint

    International Nuclear Information System (INIS)

    Lichtman, E.A.; Veterans Administration Medical Center, New York

    1983-01-01

    A heroin addict developed a Candida parapsilosis infection in a prosthetic shoulder joint. Radiographs showed loose fragments of cement with prosthetic loosening. The patient was treated with removal of the prosthesis and intravenous amphotericin B followed by oral ketoconazole. (orig.)

  20. Prosthetic management of deciduous teeth

    OpenAIRE

    Bassil, Jean

    2015-01-01

    Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Medicina Dentária Introduction: Situations of single or multiple edentulous are not an exception during childhood. Prosthetic management is necessary in case of absence of replacing tooth or when its eruption is planned too far in time. Indications of prosthetic rehabilitation for children are multiple and rise from the etiologic factors caus...

  1. Autologous grafting of extraocular muscles: experimental study in rabbits Transplante autólogo de musculatura ocular extrínseca: estudo experimental em coelhos

    Directory of Open Access Journals (Sweden)

    Jorge Meireles-Teixeira

    2005-06-01

    Full Text Available PURPOSE: To evaluate the feasibility of autologous extraocular muscle grafting as a type of muscle expansion surgery. METHODS: The left superior rectus muscle of twenty-nine rabbits was resected and this fragment was attached to the endpoint of the respective right superior rectus (test group. Thereafter, the superior rectus of the left eye was reattached to the sclera (control group. Both groups were examined during different postoperative periods in order to assess their outcomes. RESULTS: The presence of hyperemia was slightly more frequent in the grafted group. Secretion and muscle atrophy were negligible in both groups. Fibrosis was greater in grafted animals. These muscles were weaker than the control muscles, although the force required to split muscular parts was always greater than the physiological one. CONCLUSIONS: This surgical technique was reliable and useful if one intends to achieve muscle expansion without the intrinsic risks of dealing with heterologous/artificial materials.OBJETIVO: Avaliar a viabilidade do uso de segmentos de músculos oculares extrínsecos como expansores de tendões musculares. MÉTODOS: Vinte e nove coelhos tiveram seu músculo reto superior esquerdo ressecado e o fragmento de cada um foi transplantado para o reto superior contralateral (grupo-teste. Então, o reto superior esquerdo foi reinserido na esclera (grupo-controle. Os animais foram então examinados em diversos períodos pós-operatórios, até os seus sacrifícios, para que se avaliasse o desenrolar dessa técnica cirúrgica. RESULTADOS: A hiperemia foi maior entre os testes. A secreção e a atrofia muscular foram mínimas nos dois grupos. Houve maior presença de fibrose no grupo-teste, mas não tão expressiva a ponto de inviabilizar os efeitos da cirurgia. Esses músculos também se romperam mais facilmente do que os do grupo-controle, porém, a força de rompimento foi sempre bem maior do que aquela presente numa contração muscular normal

  2. The effect of cartilage and bone density of mushroom-shaped, photooxidized, osteochondral transplants: an experimental study on graft performance in sheep using transplants originating from different species

    Directory of Open Access Journals (Sweden)

    Hilbe Monika

    2005-12-01

    Full Text Available Abstract Background Differences in overall performance of osteochondral photooxidized grafts were studied in accordance of their species origin and a new, more rigorous cleansing procedure using alcohol during preparation. Methods Photooxidized mushroom-shaped grafts of bovine, ovine, human and equine origin were implanted in the femoral condyles of 32 sheep (condyles: n = 64. No viable chondrocytes were present at the time of implantation. Grafts were evaluated at 6 months using plastic embedded sections of non-decalcified bone and cartilage specimens. Graft incorporation, the formation of cyst-like lesions at the base of the cartilage junction as well as cartilage morphology was studied qualitatively, semi-quantitatively using a score system and quantitatively by performing histomorphometrical measurements of percentage of bone and fibrous tissue of the original defects. For statistical analysis a factorial analysis of variance (ANOVA- test was applied. Results Differences of graft performance were found according to species origin and cleansing process during graft preparation. According to the score system cartilage surface integrity was best for equine grafts, as well as dislocation or mechanical stability. The equine grafts showed the highest percentage for bone and lowest for fibrous tissue, resp. cystic lesions. The new, more rigorous cleansing process decreased cartilage persistence and overall graft performance. Conclusion Performance of grafts from equine origin was better compared to bovine, ovine and human grafts. The exact reason for this difference was not proven in the current study, but could be related to differences in density of cartilage and subchondral bone between species.

  3. Pancreas grafts

    International Nuclear Information System (INIS)

    Hahn, D.; Buell, U.; Land, W.; Unertl, K.

    1981-01-01

    Perfusion studies with sup(99m)Tc-DTPA, which has hitherto been used routinely to investigate renal grafts, have also proved useful for monitoring the perfusion of pancreas grafts. A total perfusion failure is equally reliably demonstrable as in renal grafts. Quantitatively smaller perfusion alterations can be demonstrated by monitoring the course. It seems possible to differentiate the salivary edema of a rejection reaction, well known from animal experiments, with the help of other paramters (e.g. creatinine). Further clinical studies are however necessary to confirm these results. (orig.) [de

  4. Control method for prosthetic devices

    Science.gov (United States)

    Bozeman, Richard J., Jr. (Inventor)

    1995-01-01

    A control system and method for prosthetic devices is provided. The control system comprises a transducer for receiving movement from a body part for generating a sensing signal associated with that movement. The sensing signal is processed by a linearizer for linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part. The linearized sensing signal is normalized to be a function of the entire range of body part movement from the no-shrug position of the moveable body part. The normalized signal is divided into a plurality of discrete command signals. The discrete command signals are used by typical converter devices which are in operational association with the prosthetic device. The converter device uses the discrete command signals for driving the moveable portions of the prosthetic device and its sub-prosthesis. The method for controlling a prosthetic device associated with the present invention comprises the steps of receiving the movement from the body part, generating a sensing signal in association with the movement of the body part, linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part, normalizing the linear signal to be a function of the entire range of the body part movement, dividing the normalized signal into a plurality of discrete command signals, and implementing the plurality of discrete command signals for driving the respective moveable prosthesis device and its sub-prosthesis.

  5. The effect of monomer molecular weight on grafting reaction

    International Nuclear Information System (INIS)

    Wu Minghong; Ding Zhongli; Ma Zueteh

    1995-01-01

    In this paper, some condensed ethylene glycol acrylate monomers with different molecular weight being grafted to the PE film by means of pre-irradiation is reported. The effect of molecular weight of monomer on grafting reaction and the hydrophilicity of grafting sample have been discussed. The experimental results show: molar degrees of grafting decreased non-linearly with the increasement of molecular weight of monomer, the grafting reaction of polymer is greater effected by the swelling degree of PE film, the greater the swelling degree of grafting material, the higher the grating degree grafting is, the initial rate of grafting reaction decreased with the increasement of molecular weight of monomer. (author)

  6. Concepts to optimize stent-grafting of abdominal aortic aneurysms based on results of experimental studies; Konzepte zur Optimierung der Stentgraftversorgung von Bauchaortenaneurysmen auf der Basis tierexperimenteller Ergebnisse

    Energy Technology Data Exchange (ETDEWEB)

    Chavan, A.; Kirchhoff, T.; Baus, S.; Galanski, M. [Medizinische Hochschule Hannover (Germany). Abt. Diagnostische Radiologie 1; Pichlmaier, M. [Medizinische Hochschule Hannover (Germany). Leibniz Forschungslab. fuer Biotechnologie und Kuenstliche Organe an der Klinik fuer Thorax-, Herz- und Gefaesschirurgie

    2001-08-01

    Purpose. In the endoluminal therapy of abdominal aortic aneurysms, a short proximal aneurysm neck, endoleaks and the large size and stiffness of the introducer systems are responsible for many of the complications and sub-optimal outcomes. The purpose of the present review article is to to suggest strategies to minimize these complications based on the results of experimental studies in animals. Material and methods. After implanting various types of stents across the renal artery origins, the functional and morphological changes in the kidneys and renal vessels were studied by various authors. In order to prevent progressive widening of the proximal aneurysmal neck and graft dislocation, Sonesson et al. performed a laparoscopic banding around the proximal neck in pigs. To study the effects of endoleaks, Marty, Schurink and Pitton carried out pressure measurements in experimental aneurysms with and without endoleaks. Sakaguchi and Pavcnik developed the 'Twin-tube endografts' (TTEG) and the 'Bifurcated drum occluder endografts' (BDOEG) and tested them in dogs. Results. Up to 3 months after suprarenal stent placement, Chavan et al. detected no significant fall in the mean inulin clearance in sheep (140{+-}46 ml/min before, 137{+-}58 ml/min after). Nasim et al. and Malina et al. reported similar observations with respect to renal function. Suprarenal fixation may result in isolated thrombotic occlusions of the renal arteries and microinfarcts in the kidneys. Mean aortic diameters at the level of banding were significantly smaller in the animals with aortic banding as opposed to those in the control group without banding (8 mm vs 11 mm, p=0.004). The banding caused a secure proximal fixation of the stent-graft. Persistent endoleaks resulted in significantly higher intraaneurysmal pressures. Although the TTEG and the BDOEG stent-grafts required smaller sheaths, occlusions were observed in 8% (TTEG) and 60% (BDOEG) of the graft limbs. (orig.) [German

  7. Cadaveric aorta implantation for aortic graft infection.

    Science.gov (United States)

    Ali, Asad; Bahia, Sandeep S S; Ali, Tahir

    2016-01-01

    This case report describes a 73-year-old gentleman who underwent explantation of an infected prosthetic aorto-iliac graft and replacement with a cryopreserved thoracic and aorto-iliac allograft. The patient has been followed up a for more than a year after surgery and remains well. After elective tube graft repair of his abdominal aortic aneurysm (AAA) in 2003, he presented to our unit in 2012 in cardiac arrest as a result of a rupture of the distal graft suture line due to infection. After resuscitation he underwent aorto-bifemoral grafting using a cuff of the original aortic graft proximally. Distally the new graft was anastomosed to his common femoral arteries, with gentamicin beads left in situ. Post discharge the patient was kept under close surveillance with serial investigations including nuclear scanning, however it became apparent that his new graft was infected and that he would require aortic graft replacement, an operation with a mortality of at least 50%. The patient underwent the operation and findings confirmed a synthetic graft infection. This tube graft was explanted and a cryopreserved aorta was used to the refashion the abdominal aorta and its bifurcation. The operation required a return to theatre day one post operatively for a bleeding side branch, which was repaired. The patient went on to make a full recovery stepping down from the intensive therapy unit day 6 post operatively and went on to be discharged 32 days after his cryopreserved aorta implantation. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  8. Animal experimental model of a graft-versus-host (GVH) reaction after allogenic transplantation of bone marrow in lethally irradiated mice

    International Nuclear Information System (INIS)

    Schwenke, H.; Muench, S.; Haubold, S.; Weber, B.

    1977-01-01

    The graft-versus-host (GVH) disease represents a serious still unsolved problem in the human allogenic transplantation of bone marrow. An experimental model of GVH reaction after an allogenic transplantation of bone marrow in the adult mouse has been worked out as a prerequisite for further studies on the therapeutic influence of this syndrome. 3 groups have been formed out of 82 lethally X-irradiated C57 Bl mice. The non-transplanted control group died to a hundred per cent within 12 days. While out of the 2nd group treated with syngenic bone marrow 55 per cent survived from the 22nd day, 30 per cent of the third animal group, allogenicly transplanted with histoincompatible AKR donor marrow developed a chronic GVH syndrome. The following symptoms were observed: retardation, alterations of the skin, diarrhea, edemas of the legs, failing increase of leukocytes in blood and proliferation of lymphocytes in bone marrow of about 60 per cent (18 per cent in syngenically transplanted animals), in lacking proliferation of hematopoiesis. The increase of liver and especially spleen index is not characteristic in comparison with the syngenically transplanted group, since in the latter there is also an increase of the values on account of a strong hematopoetic proliferation. The model is suitable and sufficiently well characterized for the performance of further experimental studies. (author)

  9. Prosthetic Mitral Valve Leaflet Escape

    Science.gov (United States)

    Kim, Darae; Hun, Sin Sang; Cho, In-Jeong; Shim, Chi-Young; Ha, Jong-Won; Chung, Namsik; Ju, Hyun Chul; Sohn, Jang Won

    2013-01-01

    Leaflet escape of prosthetic valve is rare but potentially life threatening. It is essential to make timely diagnosis in order to avoid mortality. Transesophageal echocardiography and cinefluoroscopy is usually diagnostic and the location of the missing leaflet can be identified by computed tomography (CT). Emergent surgical correction is mandatory. We report a case of fractured escape of Edward-Duromedics mitral valve 27 years after the surgery. The patient presented with symptoms of acute decompensated heart failure and cardiogenic shock. She was instantly intubated and mechanically ventilated. After prompt evaluation including transthoracic echocardiography and CT, the escape of the leaflet was confirmed. The patient underwent emergent surgery for replacement of the damaged prosthetic valves immediately. Eleven days after the surgery, the dislodged leaflet in iliac artery was removed safely and the patient recovered well. PMID:23837121

  10. Does treatment of split-thickness skin grafts with negative-pressure wound therapy improve tissue markers of wound healing in a porcine experimental model?

    Science.gov (United States)

    Ward, Christopher; Ciraulo, David; Coulter, Michael; Desjardins, Steven; Liaw, Lucy; Peterson, Sarah

    2012-08-01

    Negative-pressure wound therapy (NPWT) has been used for to treat wounds for more than 15 years and, more recently, has been used to secure split-thickness skin grafts. There are some data to support this use of NPWT, but the actual mechanism by which NPWT speeds healing or improves skin graft take is not entirely known. The purpose of this project was to assess whether NPWT improved angiogenesis, wound healing, or graft survival when compared with traditional bolster dressings securing split-thickness skin grafts in a porcine model. We performed two split-thickness skin grafts on each of eight 30 kg Yorkshire pigs. We took graft biopsies on postoperative days 2, 4, 6, 8, and 10 and submitted the samples for immunohistochemical staining, as well as standard hematoxylin and eosin staining. We measured the degree of vascular ingrowth via immunohistochemical staining for von Willenbrand's factor to better identify blood vessel epithelium. We determined the mean cross-sectional area of blood vessels present for each representative specimen, and then compared the bolster and NPWT samples. We also assessed each graft for incorporation and survival at postoperative day 10. Our analysis of the data revealed that there was no statistically significant difference in the degree of vascular ingrowth as measured by mean cross-sectional capillary area (p = 0.23). We did not note any difference in graft survival or apparent incorporation on a macroscopic level, although standard hematoxylin and eosin staining indicated that microscopically, there seemed to be better subjective graft incorporation in the NPWT samples and a nonsignificant trend toward improved graft survival in the NPWT group. We were unable to demonstrate a significant difference in vessel ingrowth when comparing NPWT and traditional bolster methods for split-thickness skin graft fixation. More studies are needed to elucidate the manner by which NPWT exerts its effects and the true clinical magnitude of these

  11. Control System for Prosthetic Devices

    Science.gov (United States)

    Bozeman, Richard J. (Inventor)

    1996-01-01

    A control system and method for prosthetic devices is provided. The control system comprises a transducer for receiving movement from a body part for generating a sensing signal associated with that of movement. The sensing signal is processed by a linearizer for linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part. The linearized sensing signal is normalized to be a function of the entire range of body part movement from the no-shrug position of the moveable body part through the full-shrg position of the moveable body part. The normalized signal is divided into a plurality of discrete command signals. The discrete command signals are used by typical converter devices which are in operational association with the prosthetic device. The converter device uses the discrete command signals for driving the moveable portions of the prosthetic device and its sub-prosthesis. The method for controlling a prosthetic device associated with the present invention comprises the steps of receiving the movement from the body part, generating a sensing signal in association with the movement of the body part, linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part, normalizing the linear signal to be a function of the entire range of the body part movement, dividing the normalized signal into a plurality of discrete command signals, and implementing the plurality of discrete command signals for driving the respective moveable prosthesis device and its sub-prosthesis.

  12. Prosthetics & Orthotics Manufacturing Initiative (POMI)

    Science.gov (United States)

    2012-12-21

    suspension system, socket- ankle /knee interface, etc.) associated with a complete prosthetic system. More specific, the purpose of these deliverables was...strap. The waist belt consists of an adjustable belt utilizing polypropylene buckles and a 2‖ elastic suspension strap which descends to the anchor ...Superior View. Step 8: The suspension component consists of a 1’ anchor strap with a buckle and a 5’ – 6’ long shoulder strap with hook and

  13. The mechanical properties of infrainguinal vascular bypass grafts: their role in influencing patency.

    Science.gov (United States)

    Sarkar, S; Salacinski, H J; Hamilton, G; Seifalian, A M

    2006-06-01

    When autologous vein is unavailable, prosthetic graft materials, particularly expanded polytetrafluoroethylene are used for peripheral arterial revascularisation. Poor long term patency of prosthetic materials is due to distal anastomotic intimal hyperplasia. Intimal hyperplasia is directly linked to shear stress abnormalities at the vessel wall. Compliance and calibre mismatch between native vessel and graft, as well as anastomotic line stress concentration contribute towards unnatural wall shear stress. High porosity reduces graft compliance by causing fibrovascular infiltration, whereas low porosity discourages the development of an endothelial lining and hence effective antithrombogenicity. Therefore, consideration of mechanical properties is necessary in graft development. Current research into synthetic vascular grafts concentrates on simulating the mechanical properties of native arteries and tissue engineering aims to construct a new biological arterial conduit.

  14. Histologic and histomorphometric evaluation of bone regeneration using nanocrystalline hydroxyapatite and human freeze-dried bone graft : An experimental study in rabbit.

    Science.gov (United States)

    Sadeghi, Rokhsareh; Najafi, Mohammad; Semyari, Hassan; Mashhadiabbas, Fatemeh

    2017-03-01

    Bone regeneration is an important concern in periodontal treatment and implant dentistry. Different biomaterials and surgical techniques have been used for this purpose. The aim of the present study was to compare the effect of nanocrystalline hydroxyapatite and human freeze-dried bone graft (FDBG) in regeneration of rabbit calvarium bony defects by histologic and histomorphometric evaluation. In this experimental study, three similar defects, measuring 8 mm in diameter, were created in the calvaria of 16 white New Zealand rabbits. Two defects were filled with FDBG and nanocrystalline hydroxyapatite silica gel, while the other one remained unfilled to be considered as control. All the defects were covered with collagen membranes. During the healing period, two animals perished; so 14 rabbits were divided into two groups: half of them were euthanized after 6 weeks of healing and the other half after 12 weeks. The specimens were subjected to histologic and histomorphometric examinations for assessment of the following variables: percentage of bone formation and residual graft material, inflammation scores, patterns of bone formation and type of newly formed bone. The percentages of new bone formation after 6 weeks were 14.22 ± 7.85, 21.57 ± 6.91, and 20.54 ± 10.07% in FDBG, NanoBone, and control defects. These values were 27.54 ± 20.19, 23.86 ± 6.27, and 26.48 ± 14.18% in 12-week specimens, respectively. No significant differences were found in the amount of bone formation between the groups. With regard to inflammation, the control and NanoBone groups showed significantly less inflammation compared to FDBG at the 6-week healing phase (P = 0.04); this difference was not significant in the 12-week specimens. Based on the results of this experimental study, both NanoBone and FDBG exhibited a similar effect on bone formation.

  15. Bone response to collagenized xenografts of porcine origin (mp3(®) ) and a bovine bone mineral grafting (4BONE(™) XBM) grafts in tibia defects: experimental study in rabbits.

    Science.gov (United States)

    Calvo-Guirado, José Luis; Aguilar-Salvatierra, Antonio; Ramírez-Fernández, Maria P; Maté Sánchez de Val, José E; Delgado-Ruiz, Rafael Arcesio; Gómez-Moreno, Gerardo

    2016-08-01

    This study aimed to carry out the evaluation of bone response of new bone formation to two different xenografts (bovine and porcine) biomaterials inserted in rabbit tibiae. The study used a total of 20 male New Zealand albino rabbits. They received a total of 40 grafts in the proximal metaphyseal areas of both tibiae. Two biomaterials were evaluated: 20 porcine xenografts, as a bone granulate (OsteoBiol(®) MP3(®) ; Tecnoss srl, Giaveno, Italy), were placed in the proximal metaphyseal area of the right tibia, 20 anorganic bovine bone mineral grafting (4BONE(™) XBM, MIS Implants Inc., BARLEV, Israel) were placed in the left tibia. Following graft insertion, the animals were sacrificed in two groups of 10 animals, after 1 and 4 months, respectively. For each group, biomaterials were analyzed: newly formed bone, residual graft materials and the connective tissue. Histomorphometric, EDX analysis and element mapping were performed at 1 and 4 months after graft insertion. At 4 months after treatment, the bone defects displayed radiological images that showed complete repair of osseous defects. Histomorphometric evaluation showed that for the porcine xenograft, the study averages for newly formed bone represented 84.23 ± 2.9%, while bovine matrix was 79.34 ± 2.1%. For residual graft material, the porcine biomaterial had 11.23 ± 1.7% and the bovine graft 31.56 ± 2.3%. Finally, the connective tissue for MP3 was 10.33 ± 1.8%, while for the 4BONE(™) XBM we obtained 14.34 ± 2.9%. Element analysis revealed higher percentages of Ca (54 ± 9%) and P (35 ± 6%) in the group B than group A and control group (P MP3 material; this supports new bone formation, creates a bridge between borders, and facilitates bone ingrowth in both biomaterials. Furthermore, this study observed partial dissolution of the mineral phase of four bone graft and complete resorption of porcine MP3 biomaterial and its incorporation into the surrounding bone. Depending on

  16. Calcification of a Synthetic Renovascular Graft in a Child

    Directory of Open Access Journals (Sweden)

    D.S.T. Chong

    Full Text Available : Introduction: Vascular grafts, especially in paediatric cases, need to be durable. Common failures such as thrombosis are well documented with research efforts directed towards them. However, there are lesser known causes of graft failure, such as graft calcification, and these also require further research focus. Report: A paediatric case is described in which a synthetic renovascular graft, implanted for mid-aortic syndrome, became calcified, necessitating surgical intervention to resolve graft malfunction. Significant calcification in the limb of a bifurcated polyethylene terephthalate graft was found to be the cause of resistant stenosis and refractory hypertension. Histology conducted on the explanted limb showed the presence of multinuclear giant cells, indicating a chronic foreign body response. Discussion: Calcification of vascular grafts is probably more common than previously recognised. Stenosis typically resistant to angioplasty may result in the long term and thus leading to surgical intervention. In young children, this is suboptimal as these grafts need to last throughout adulthood. Explanted prosthetic grafts should be sent to specialist registries such as that in Strasbourg to be optimally assessed so that contributory factors can be identified. Keywords: Renovascular graft, Paediatric, Calcification

  17. Fifteen years of follow-up of a removable prosthetic design to maintain two remaining molars in a patient with mandibular reconstruction

    Directory of Open Access Journals (Sweden)

    Ming-Lun Hsu

    2012-06-01

    Full Text Available This clinical report describes a long-term prosthetic solution for a patient who had undergone mandibular reconstruction with a fibular graft, leaving only two right molars. The only retention device for the removable prosthesis design included a telescoping system with an O-ring application, but without fibula graft involvement. This prosthesis design was motivated by the altered bony and muscular architecture resulting in an increased maxillomandibular space and thick soft tissue in the denture-bearing area. This case demonstrates that appropriate denture design, consistent recall maintenance, and oral hygiene motivation minimized periodontal destruction and maximized prosthetic use for the patient despite the unfavorable loading conditions.

  18. Computer Aided Facial Prosthetics Manufacturing System

    Directory of Open Access Journals (Sweden)

    Peng H.K.

    2016-01-01

    Full Text Available Facial deformities can impose burden to the patient. There are many solutions for facial deformities such as plastic surgery and facial prosthetics. However, current fabrication method of facial prosthetics is high-cost and time consuming. This study aimed to identify a new method to construct a customized facial prosthetic. A 3D scanner, computer software and 3D printer were used in this study. Results showed that the new developed method can be used to produce a customized facial prosthetics. The advantages of the developed method over the conventional process are low cost, reduce waste of material and pollution in order to meet the green concept.

  19. Circuit For Control Of Electromechanical Prosthetic Hand

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1995-01-01

    Proposed circuit for control of electromechanical prosthetic hand derives electrical control signals from shoulder movements. Updated, electronic version of prosthesis, that includes two hooklike fingers actuated via cables from shoulder harness. Circuit built around favored shoulder harness, provides more dexterous movement, without incurring complexity of computer-controlled "bionic" or hydraulically actuated devices. Additional harness and potentiometer connected to similar control circuit mounted on other shoulder. Used to control stepping motor rotating hand about prosthetic wrist to one of number of angles consistent with number of digital outputs. Finger-control signals developed by circuit connected to first shoulder harness transmitted to prosthetic hand via sliprings at prosthetic wrist joint.

  20. Distal anastomotic vein adjunct usage in infrainguinal prosthetic bypasses.

    Science.gov (United States)

    McPhee, James T; Goodney, Philip P; Schanzer, Andres; Shaykevich, Shimon; Belkin, Michael; Menard, Matthew T

    2013-04-01

    Single-segment saphenous vein remains the optimal conduit for infrainguinal revascularization. In its absence, prosthetic conduit may be used. Existing data regarding the significance of anastomotic distal vein adjunct (DVA) usage with prosthetic grafts are based on small series. This is a retrospective cohort analysis derived from the regional Vascular Study Group of New England as well as the Brigham and Women's hospital database. A total of 1018 infrainguinal prosthetic bypass grafts were captured in the dataset from 73 surgeons at 15 participating institutions. Propensity scoring and 3:1 matching was performed to create similar exposure groups for analysis. Outcome measures of interest included: primary patency, freedom from major adverse limb events (MALEs), and amputation free survival at 1 year as a function of vein patch utilization. Time to event data were compared with the log-rank test; multivariable Cox proportional hazard models were used to evaluate the adjusted association between vein cuff usage and the primary end points. DVA was defined as a vein patch, cuff, or boot in any configuration. Of the 1018 bypass operations, 94 (9.2%) had a DVA whereas 924 (90.8%) did not (no DVA). After propensity score matching, 88 DVAs (25%) and 264 no DVAs (75%) were analyzed. On univariate analysis of the matched cohort, the DVA and no DVA groups were similar in terms of mean age (70.0 vs 69.0; P = .55), male sex (58.0% vs 58.3%; P > .99), and preoperative characteristics such as living at home (93.2% vs 94.3%; P = .79) and independent ambulatory status (72.7% vs 75.7%; P = .64). The DVA and no DVA groups had similar rates of major comorbidities such as hypertension chronic obstructive pulmonary disease, diabetes mellitus, coronary artery disease, and dialysis dependence (P > .05 for all). Likewise, they had similar rates of distal origin grafts (13.6% vs 12.5%; P = .85), critical limb ischemia indications (P = .53), and prior arterial bypass (58% vs 47%; P = .08

  1. Stent graft placement for dysfunctional arteriovenous grafts

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Gyeong Sik [Dept. of Radiology, CHA Bundang Medical Center, College of Medicine, CHA University, Seongnam (Korea, Republic of); Shin, Byung Seok; Ohm, Joon Young; Ahn, Moon Sang [Chungnam National University Hospital, Daejeon (Korea, Republic of)

    2015-07-15

    This study aimed to evaluate the usefulness and outcomes of stent graft use in dysfunctional arteriovenous grafts. Eleven patients who underwent stent graft placement for a dysfunctional hemodialysis graft were included in this retrospective study. Expanded polytetrafluoroethylene covered stent grafts were placed at the venous anastomosis site in case of pseudoaneurysm, venous laceration, elastic recoil or residual restenosis despite the repeated angioplasty. The patency of the arteriovenous graft was evaluated using Kaplan-Meier analysis. Primary and secondary mean patency was 363 days and 741 days. Primary patency at 3, 6, and 12 months was 82%, 73%, and 32%, respectively. Secondary patency at the 3, 6, 12, 24, and 36 months was improved to 91%, 82%, 82%, 50%, and 25%, respectively. Fractures of the stent graft were observed in 2 patients, but had no effect on the patency. Stent graft placement in dysfunctional arteriovenous graft is useful and effective in prolonging graft patency.

  2. Hypertrophic osteoarthropathy of one leg - a sign of aortic graft infection

    Energy Technology Data Exchange (ETDEWEB)

    Spruijt, S.; Krijgsman, A.A. [Department of Orthopaedic and Trauma Surgery, Elkerliek Hospital, Helmond (Netherlands); Broek, J.A.C. van den [Department of Radiology, Elkerliek Hospital, Helmond (Netherlands); Tutein Nolthenius-Puylaert, M.C.B.J.E. [Department of Pathology, Elkerliek Hospital, Helmond (Netherlands)

    1999-04-01

    We report a rare case of hypertrophic osteoarthropathy (HOA) confined to the right leg secondary to aortic graft infection. The development of HOA exclusively localized to areas distal to a vascular prosthesis may be the presenting manifestation of graft infection and a crucial diagnostic clue in the early detection of vascular graft infection. HOA is diagnosed by its characteristic radiographic and scintigraphic pattern. Most prosthetic, especially aortic, graft infections are uniformly fatal if not treated by aggressive surgical and antibiotic therapy. Recognition of this uncommon association may facilitate an early diagnosis, which usually requires immediate surgical therapy. (orig.) With 6 figs., 28 refs.

  3. Hypertrophic osteoarthropathy of one leg - a sign of aortic graft infection

    International Nuclear Information System (INIS)

    Spruijt, S.; Krijgsman, A.A.; Broek, J.A.C. van den; Tutein Nolthenius-Puylaert, M.C.B.J.E.

    1999-01-01

    We report a rare case of hypertrophic osteoarthropathy (HOA) confined to the right leg secondary to aortic graft infection. The development of HOA exclusively localized to areas distal to a vascular prosthesis may be the presenting manifestation of graft infection and a crucial diagnostic clue in the early detection of vascular graft infection. HOA is diagnosed by its characteristic radiographic and scintigraphic pattern. Most prosthetic, especially aortic, graft infections are uniformly fatal if not treated by aggressive surgical and antibiotic therapy. Recognition of this uncommon association may facilitate an early diagnosis, which usually requires immediate surgical therapy. (orig.)

  4. Update on Bioactive Prosthetic Material for the Treatment of Hernias.

    Science.gov (United States)

    Edelman, David S; Hodde, Jason P

    2011-12-01

    The use of mesh in the repair of hernias is commonplace. Synthetic mesh, like polypropylene, has been the workhorse for hernia repairs since the 1980s. Surgisis® mesh (Cook Surgical, Bloomington, IN), a biologic hernia graft material composed of purified porcine small intestinal submucosa (SIS), was first introduced to the United States in 1998 as an alternative to synthetic mesh materials. This mesh, composed of extracellular matrix collagen, fibronectin and associated glycosaminoglycans and growth factors, has been extensively investigated in animal models and used clinically in many types of surgical procedures. SIS acts as a scaffold for natural growth and strength. We reported our initial results in this publication in July 2006. Since then, there have been many more reports and numerous other bioactive prosthetic materials (BPMs) released. The object of this article is to briefly review some of the current literature on the use of BPM for inguinal hernias, sports hernias, and umbilical hernias.

  5. Fifteen years of follow-up of a removable prosthetic design to maintain two remaining molars in a patient with mandibular reconstruction

    OpenAIRE

    Ming-Lun Hsu; Jacqueline Chia-Hsuan Wu; Ling-Ming Yu

    2012-01-01

    This clinical report describes a long-term prosthetic solution for a patient who had undergone mandibular reconstruction with a fibular graft, leaving only two right molars. The only retention device for the removable prosthesis design included a telescoping system with an O-ring application, but without fibula graft involvement. This prosthesis design was motivated by the altered bony and muscular architecture resulting in an increased maxillomandibular space and thick soft tissue in the den...

  6. Prosthetic

    Directory of Open Access Journals (Sweden)

    Pokpong Amornvit

    2014-01-01

    Full Text Available Ocular trauma can be caused by road traffic accidents, falls, assaults, or work-related accidents. Enucleation is often indicated after ocular injury or for the treatment of intraocular tumors, severe ocular infections, and painful blind eyes. Rehabilitation of an enucleated socket without an intraocular implant or with an inappropriately sized implant can result in superior sulcus deepening, enophthalmos, ptosis, ectropion, and lower lid laxity, which are collectively known as post-enucleation socket syndrome. This clinical report describes the rehabilitation of post-enucleation socket syndrome with a modified ocular prosthesis. Modifications to the ocular prosthesis were performed to correct the ptosis, superior sulcus deepening, and enophthalmos. The rehabilitation procedure produced satisfactory results.

  7. Open Repair of Mycotic Abdominal Aortic Aneurysms With Biological Grafts

    DEFF Research Database (Denmark)

    Heinola, Ivika; Sörelius, Karl; Wyss, Thomas R

    2018-01-01

    BACKGROUND: The treatment of mycotic abdominal aortic aneurysm requires surgery and antimicrobial therapy. Since prosthetic reconstructions carry a considerable risk of reinfection, biological grafts are noteworthy alternatives. The current study evaluated the durability, infection resistance......, and midterm outcome of biological grafts in treatment of mycotic abdominal aortic aneurysm. METHODS AND RESULTS: All patients treated with biological graft in 6 countries between 2006 and 2016 were included. Primary outcome measures were 30- and 90-day survival, treatment-related mortality, and reinfection...... rate. Secondary outcome measures were overall mortality and graft patency. Fifty-six patients (46 males) with median age of 69 years (range 35-85) were included. Sixteen patients were immunocompromised (29%), 24 (43%) had concomitant infection, and 12 (21%) presented with rupture. Bacterial culture...

  8. Fully 3-dimensional digitally planned reconstruction of a mandible with a free vascularized fibula and immediate placement of an implant-supported prosthetic construction

    NARCIS (Netherlands)

    Schepers, Rutger H.; Raghoebar, Gerry M.; Vissink, Arjan; Lahoda, Lars U.; Van der Meer, W. Joerd; Roodenburg, Jan L.; Reintsema, Harry; Witjes, Max J.

    Background Reconstruction of craniofacial defects becomes complex when dental implants are included for functional rehabilitation. We describe a fully 3-dimensional (3D) digitally planned reconstruction of a mandible and immediate prosthetic loading with a fibula graft in a 2-step surgical approach.

  9. Bone Graft Alternatives

    Science.gov (United States)

    ... Spine Treatment Spondylolisthesis BLOG FIND A SPECIALIST Treatments Bone Graft Alternatives Patient Education Committee Patient Education Committee ... procedure such as spinal fusion. What Types of Bone Grafts are There? Bone grafts that are transplanted ...

  10. Effects of a flat prosthetic foot rocker section on balance and mobility.

    Science.gov (United States)

    Hansen, Andrew; Nickel, Eric; Medvec, Joseph; Brielmaier, Steven; Pike, Alvin; Weber, Marilyn

    2014-01-01

    Previous studies have shown that the effective rocker shape of the physiologic ankle-foot system during standing and fore-aft swaying is much flatter than that used during walking, which indicates a more stable base of support for the standing/swaying activity. Previous work suggests that flat regions within the effective rocker shapes of prosthetic ankle-foot systems could provide enhanced stability for standing balance tasks. An experimental prosthetic foot was altered to provide three different flat region lengths within its effective rocker shape. It was hypothesized that longer flat regions of the effective rocker shape would lead to improved standing balance outcomes and reduced walking performance for unilateral transtibial prosthesis users. However, no significant changes were seen in the balance and mobility outcomes of 12 unilateral transtibial prosthesis users when using the three prosthetic foot conditions. Subjects in the study significantly preferred prosthetic feet with relatively low to moderate flat regions over those with long flat regions. All the subjects without loss of light touch or vibratory sensation selected the prosthetic foot with the shortest flat region. More work is needed to investigate the effects of prosthetic foot properties on balance and mobility of prosthesis users.

  11. Ruptured peroneal aneurysm after infrapopliteal prosthetic bypass with Taylor patch

    Directory of Open Access Journals (Sweden)

    Florian Enzmann

    Full Text Available Introduction: A 45-year-old mailman underwent an implantation of a femoro-peroneal polytetrafluoroethylene (PTFE bypass with a distal Taylor patch six years prior to admission after two failed autologous reconstructions and extensive fasciotomy. The initial pathology was an acute ischemia due to popliteal entrapment with subsequent popliteal thrombectomy. Report: The patient was examined because of pain, reduction of walking distance and development of a palpable mass at the medial fasciotomy site. A 6-cm pseudoaneurysm with complete disruption of the suture line of the vein patch was discovered and resected. Arterial continuity with a vein interposition graft was established using non-reversed cephalic vein. Conclusion: The etiology of the aneurysm is not entirely clear. One may argue that the fourth revascularization could have been performed with an arm vein instead of a prosthetic graft with the probability of a better long term patency in a young patient. 15 months after the procedure the bypass is patent and the patient is without any symptoms. This complication of a Taylor patch has not been reported before. Keywords: Taylor patch, Pseudoaneurysm, Infrapopliteal bypass

  12. EEG Mind Controlled Smart Prosthetic Arm – A Comprehensive Study

    Directory of Open Access Journals (Sweden)

    Taha Beyrouthy

    2017-06-01

    Full Text Available Recently, the field of prosthetics has seen many accomplishments especially with the integration of technological advancements. In this paper, different arm types (robotic, surgical, bionic, prosthetic and static are analyzed in terms of resistance, usage, flexibility, cost and potential. Most of these techniques have some problems; they are extremely expensive, hard to install and maintain and may require surgery. Therefore, our work introduces the initial design of an EEG mind controlled smart prosthetic arm. The arm is controlled by the brain commands, obtained from an electroencephalography (EEG headset, and equipped with a network of smart sensors and actuators that give the patient intelligent feedback about the surrounding environment and the object in contact. This network provides the arm with normal hand functionality, smart reflexes and smooth movements. Various types of sensors are used including temperature, pressure, ultrasonic proximity sensors, accelerometers, potentiometers, strain gauges and gyroscopes. The arm is completely 3D printed built from various lightweight and high strength materials that can handle high impacts and fragile elements as well. Our project requires the use of nine servomotors installed at different places in the arm. Therefore, the static and dynamic modes of servomotors are analyzed. The total cost of the project is estimated to be relatively cheap compared to other previously built arms. Many scenarios are analyzed corresponding to the actions that the prosthetic arm can perform, and an algorithm is created to match these scenarios. Experimental results show that the proposed EEG Mind-controlled Arm is a promising alternative for current solutions that require invasive and expensive surgical procedures.

  13. Advanced upper limb prosthetic devices: implications for upper limb prosthetic rehabilitation.

    Science.gov (United States)

    Resnik, Linda; Meucci, Marissa R; Lieberman-Klinger, Shana; Fantini, Christopher; Kelty, Debra L; Disla, Roxanne; Sasson, Nicole

    2012-04-01

    The number of catastrophic injuries caused by improvised explosive devices in the Afghanistan and Iraq Wars has increased public, legislative, and research attention to upper limb amputation. The Department of Veterans Affairs (VA) has partnered with the Defense Advanced Research Projects Agency and DEKA Integrated Solutions to optimize the function of an advanced prosthetic arm system that will enable greater independence and function. In this special communication, we examine current practices in prosthetic rehabilitation including trends in adoption and use of prosthetic devices, financial considerations, and the role of rehabilitation team members in light of our experiences with a prototype advanced upper limb prosthesis during a VA study to optimize the device. We discuss key challenges in the adoption of advanced prosthetic technology and make recommendations for service provision and use of advanced upper limb prosthetics. Rates of prosthetic rejection are high among upper limb amputees. However, these rates may be reduced with sufficient training by a highly specialized, multidisciplinary team of clinicians, and a focus on patient education and empowerment throughout the rehabilitation process. There are significant challenges emerging that are unique to implementing the use of advanced upper limb prosthetic technology, and a lack of evidence to establish clinical guidelines regarding prosthetic prescription and treatment. Finally, we make recommendations for future research to aid in the identification of best practices and development of policy decisions regarding insurance coverage of prosthetic rehabilitation. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  14. Echocardiographic evaluation of heart valve prosthetic dysfunction

    Directory of Open Access Journals (Sweden)

    Yuriy Ivaniv

    2018-02-01

    Full Text Available Patients with replaced heart valve submitted to echocardiographic examination may have symptoms related either to valvular malfunction or ventricular dysfunction from different causes. Clinical examination is not reliable in a prosthetic valve evaluation and the main information regarding its function could be obtained using different cardiac ultrasound modalities. This review provides a description of echocardiographic and Doppler techniques useful in evaluation of prosthetic heart valves. For the interpretation of echocardiography there is a need in special knowledge of prosthesis types and possible reasons of prosthetic function deterioration. Echocardiography allows to reveal valve thrombosis, pannus formation, vegetation and such complications of infective endocarditis as valve ring abscess or dehiscence. Transthoracic echocardiography requires different section plane angles and unconventional views. Transesophageal echocardiography is more often used than in native valve examination due to better visualization of prosthetic valve structure and function. Three-dimensional echocardiography could provide more detailed visual information especially in the assessment of paravalvular regurgitation or valve obstruction.

  15. DME Prosthetics Orthotics, and Supplies Fee Schedule

    Data.gov (United States)

    U.S. Department of Health & Human Services — Durable Medical Equipment, Prosthetics-Orthotics, and Supplies Fee Schedule. The list contains the fee schedule amounts, floors, and ceilings for all procedure codes...

  16. Computed Tomography of Prosthetic Heart Valves

    NARCIS (Netherlands)

    Habets, J.

    2012-01-01

    Prosthetic heart valve (PHV) dysfunction is an infrequent but potentially life-threatening disease with a heterogeneous clinical presentation. Patients with PHV dysfunction clinically can present with symptoms of congestive heart failure (dyspnea, fatigue, edema), fever, angina pectoris, dizziness

  17. Peri-prosthetic fracture vibration testing

    Energy Technology Data Exchange (ETDEWEB)

    Cruce, Jesse R [Los Alamos National Laboratory; Erwin, Jenny R [Los Alamos National Laboratory; Remick, Kevin R [Los Alamos National Laboratory; Cornwell, Phillip J [Los Alamos National Laboratory; Menegini, R. Michael [INDIANA UNIV.; Racanelli, Joe [STRYKER ORTHOPARDICS

    2010-11-08

    The purpose of this study was to establish a test setup and vibration analysis method to predict femoral stem seating and prevent bone fracture using accelerometer and force response data from an instrumented stem and impactor. This study builds upon earlier studies to identify a means to supplement a surgeon's tactile and auditory senses by using damage identification techniques normally used for civil and mechanical structures. Testing was conducted using foam cortical shell sawbones prepared for stems of different geometries. Each stem was instrumented with an accelerometer. Two impactor designs were compared: a monolithic impactor and a two-piece impactor, each with an integrated load cell and accelerometer. Acceleration and force measurements were taken in the direction of impaction. Comparisons between different methods of applying an impacting force were made, including a drop tower and a surgical hammer. The effect of varying compliance on the data was also investigated. The ultimate goal of this study was to assist in the design of an integrated portable data acquisition system capable of being used in future cadaveric testing. This paper will discuss the experimental setup and the subsequent results of the comparisons made between impactors, prosthetic geometries, compliances, and impact methods. The results of this study can be used for both future replicate testing as well as in a cadaveric environment.

  18. Isolated Lactobacillus chronic prosthetic knee infection.

    Science.gov (United States)

    Bennett, David M; Shekhel, Tatyana; Radelet, Matt; Miller, Michael D

    2014-01-01

    Lactobacillus is a gram-positive rod bacteria found primarily in the gastrointestinal and female genital tracts. Prosthetic infections in implants are being increasingly reported. The authors present a case of a 58-year-old patient with Lactobacillus septic prosthetic knee joint infection. To the authors’ knowledge, this is the first reported case of chronic prosthetic knee infection with isolated Lactobacillus species. Lactobacillus has been most commonly implicated with bacteremia and endocarditis and rarely with pneumonia, meningitis, and endovascular infection, and a vast majority of the cases are reported in immunocompromised patients. In the current case, diabetes mellitus, hepatitis, malnutrition, anemia, and liver failure were comorbid conditions, placing the patient at increased risk of infection. The findings suggest that further case series are necessary to establish the significance of Lactobacillus as an etiologic agent in chronic low-virulence, and potentially vancomycin-resistant, prosthetic joint infection. The need also exists for further research aimed at the risk of prosthetic joint infection with oral intake of certain probiotic foods and supplements. The goal of this case report is to bring to light the potential of this organism to be a cause of subtle chronic prosthetic joint infection.

  19. [Treatment of the infected wound with exposed silver-ring vascular graft and delayed Thiersch method of skin transplant covering ].

    Science.gov (United States)

    Nenezić, Dragoslav; Pandaitan, Simon; Ilijevski, Nenad; Matić, Predrag; Gajin, Predag; Radak, Dorde

    2005-01-01

    Although the incidence of prosthetic infection is low (1%-6%), the consequences (limb loss or death) are dramatic for a patient, with high mortality rate (25%-75%) and limb loss in 40%-75% of cases. In case of Szilagyi's grade III infection, standard procedure consists of the excision of prosthesis and wound debridement. Alternative method is medical treatment. This is a case report of a patient with prosthetic infection of Silver-ring graft, used for femoropopliteal reconstruction, in whom an extreme skin necrosis developed in early postoperative period. This complication was successfully treated medically. After repeated debridement and wound-packing, the wound was covered using Thiersch skin graft.

  20. Cetacean Swimming with Prosthetic Limbs

    Science.gov (United States)

    Bode-Oke, Ayodeji; Ren, Yan; Dong, Haibo; Fish, Frank

    2016-11-01

    During entanglement in fishing gear, dolphins can suffer abrasions and amputations of flukes and fins. As a result, if the dolphin survives the ordeal, swimming performance is altered. Current rehabilitation technques is the use of prosthesis to regain swimming ability. In this work, analyses are focused on two dolphins with locomotive impairment; Winter (currently living in Clearwater Marine Aquarium in Florida) and Fuji (lived in Okinawa Churaumi Aquarium in Japan). Fuji lost about 75% of its fluke surface to necrosis (death of cells) and Winter lost its tail due to amputation. Both dolphins are aided by prosthetic tails that mimic the shape of a real dolphin tail. Using 3D surface reconstruction techniques and a high fidelity Computational Fluid Dynamics (CFD) flow solver, we were able to elucidate the kinematics and hydrodynamics and fluke deformation of these swimmers to clarify the effectiveness of prostheses in helping the dolphins regain their swimming ability. Associated with the performance, we identified distinct features in the wake structures that can explain this gap in the performance compared to a healthy dolphin. This work was supported by ONR MURI Grant Number N00014-14-1-0533.

  1. Computed tomography evaluation of autogenous graft in sinus lift surgery

    International Nuclear Information System (INIS)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro; Alves, Maria Teresa de Seixas

    2001-01-01

    The objective was to quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from apheresis or centrifugation using computed tomography. This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by apheresis. The results showed that computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. It was concluded that clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants. (author)

  2. Autologous fat graft in irradiated orbit postenucleation for retinoblastoma.

    Science.gov (United States)

    Klinger, Francesco; Maione, Luca; Vinci, Valeriano; Lisa, Andrea; Barbera, Federico; Balia, Laura; Caviggioli, Fabio; Di Maria, Alessandra

    2018-01-05

    Autologous fat grafting has been extensively and successfully adopted in a number of pathologic conditions in regenerative surgery especially on irradiated fields in order to improve pain symptoms and tissue trophism promoting scar release. In the present study, we report our experience with autologous fat grafting for the treatment of postirradiation fibrosis and pain on three consecutive patients undergoing orbital enucleation for locally advanced retinoblastoma (RB) and subsequent radiotherapy. We selected three consecutive patients who underwent orbital enucleation for locally advanced RB and subsequent local radiotherapy showing severe reduction in orbital volume and eyelid length and retraction due to fibrosis, spontaneous local pain exacerbated after digital pressure with no possibility to place an ocular implant. They underwent autologous fat grafting in the orbital cavity and results were evaluated by clinical examination at 5 and 14 days, and 1, 3, 6 months, and 1 year after surgery. A significant release of scar retraction, reduction of fibrosis and orbital rim contraction together with an important improvement of pain symptoms was observed in all patients. The local changes observed enabled an ease placement of an ocular prosthetic implant (implant). No local or systemic complication occurred. Fat grafting is a promising treatment for patients showing radiotherapy related complication in the orbital area and it should be adopted by all oculoplastic surgeon in order to improve pain syndrome creating the ideal local conditions for the placement of an ocular prosthetic implant.

  3. Bone grafting: An overview

    Directory of Open Access Journals (Sweden)

    D. O. Joshi

    2010-08-01

    Full Text Available Bone grafting is the process by which bone is transferred from a source (donor to site (recipient. Due to trauma from accidents by speedy vehicles, falling down from height or gunshot injury particularly in human being, acquired or developmental diseases like rickets, congenital defects like abnormal bone development, wearing out because of age and overuse; lead to bone loss and to replace the loss we need the bone grafting. Osteogenesis, osteoinduction, osteoconduction, mechanical supports are the four basic mechanisms of bone graft. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. An ideal bone graft material is biologically inert, source of osteogenic, act as a mechanical support, readily available, easily adaptable in terms of size, shape, length and replaced by the host bone. Except blood, bone is grafted with greater frequency. Bone graft indicated for variety of orthopedic abnormalities, comminuted fractures, delayed unions, non-unions, arthrodesis and osteomyelitis. Bone graft can be harvested from the iliac crest, proximal tibia, proximal humerus, proximal femur, ribs and sternum. By adopting different procedure of graft preservation its antigenicity can be minimized. The concept of bone banking for obtaining bone grafts and implants is very useful for clinical application. Absolute stability require for successful incorporation. Ideal bone graft must possess osteogenic, osteoinductive and osteocon-ductive properties. Cancellous bone graft is superior to cortical bone graft. Usually autologous cancellous bone graft are used as fresh grafts where as allografts are employed as an alloimplant. None of the available type of bone grafts possesses all these properties therefore, a single type of graft cannot be recomm-ended for all types of orthopedic abnormalities. Bone grafts and implants can be selected as per clinical problems, the equipments available and preference of

  4. Determination of the distribution of graft yields following a radiation-induced graft copolymerization

    International Nuclear Information System (INIS)

    Schipschack, K.; Wagner, H.; Sawtschenko, L.

    1976-01-01

    In the radiation-induced graft copolymerization on solid initial polymers a distribution of graft yields takes place along the cross-sections of samples. Methods for determining this distribution, which are described in the literature, are reviewed. In our own investigations boards made of ethylene-vinyl acetate copolymers and grafted with vinyl chloride were used. Distributions of the grafted component obtained by infrared analysis of microtome cuts parallel to the surface are partly rather inhomogeneous, and are interpreted as dependent on the experimental parameters. (author)

  5. Validation of the prosthetic esthetic index

    DEFF Research Database (Denmark)

    Özhayat, Esben B; Dannemand, Katrine

    2014-01-01

    OBJECTIVES: In order to diagnose impaired esthetics and evaluate treatments for these, it is crucial to evaluate all aspects of oral and prosthetic esthetics. No professionally administered index currently exists that sufficiently encompasses comprehensive prosthetic esthetics. This study aimed...... to validate a new comprehensive index, the Prosthetic Esthetic Index (PEI), for professional evaluation of esthetics in prosthodontic patients. MATERIAL AND METHODS: The content, criterion, and construct validity; the test-retest, inter-rater, and internal consistency reliability; and the sensitivity...... furthermore distinguish between participants and controls, indicating sufficient sensitivity. CONCLUSION: The PEI is considered a valid and reliable instrument involving sufficient aspects for assessment of the professionally evaluated esthetics in prosthodontic patients. CLINICAL RELEVANCE...

  6. Responsiveness of the Prosthetic Esthetic Scale

    DEFF Research Database (Denmark)

    Øzhayat, Esben Boeskov

    2017-01-01

    Objectives The aim of the study was to evaluate the responsiveness of the Prosthetic Esthetic Index (PEI) in a population who received prosthetic replacements. Materials and methods Fifty-seven patients who received prosthetic replacement of at least one tooth by means of fixed or removable...... prosthesis were professionally esthetically evaluated using the PEI and the Dental Aesthetic Index (DAI) before and after treatment. The participants further evaluated their oral esthetics using the Oral Health Impact Profile Aesthetic (OHIP-Aes) and Orofacial Esthetic Index (OES). Responsiveness......-Aes and OES scores. The PEI was more consistent in responsiveness than the DAI. Conclusions The PEI shows sufficient responsiveness for use in longitudinal studies and for use as a follow-up measure in clinical practice. Clinical relevance The PEI can in a standardized manner monitor and document esthetic...

  7. Ten questions on prosthetic shoulder infection.

    Science.gov (United States)

    Pinder, Elizabeth M; Ong, Joshua Cy; Bale, R Stephen; Trail, Ian A

    2016-07-01

    Prosthetic shoulder infection can cause significant morbidity secondary to pain and stiffness. Symptoms may be present for years before diagnosis because clinical signs are often absent and inflammatory markers may be normal. An emerging common culprit, Propionibacterium acnes, is hard to culture and so prolonged incubation is necessary. A negative culture result does not always exclude infection and new synovial fluid biochemical markers such as α defensin are less sensitive than for lower limb arthroplasty. A structured approach is necessary when assessing patients for prosthetic shoulder joint infection. This includes history, examination, serum inflammatory markers, plain radiology and aspiration and/or biopsy. A classification for the likelihood of prosthetic shoulder infection has been described based on culture, pre-operative and intra-operative findings. Treatment options include antibiotic suppression, debridement with component retention, one-stage revision, two-stage revision and excision arthroplasty. Revision arthroplasty is associated with the best outcomes.

  8. Utilização da veia glicerolada na regeneração neural: Estudo experimental em ratos The use of glycerol-treated venous graft in damaged nerves repair: an experimental study in rats

    Directory of Open Access Journals (Sweden)

    Armando dos Santos Cunha

    2007-01-01

    Full Text Available A auto-enxertia de nervo é o tratamento de escolha para grandes perdas de tecido neural que não podem ser reparadas por meio de rafia primária. A utilização do enxerto venoso previamente conservado em glicerol seria uma alternativa para diminuir o tempo operatório e a morbidade cirúrgica nesses casos. Os vasos preservados em glicerol não apresentam destruição de sua estrutura, o que permite seu uso na microcirurgia vascular, tendo a vantagem de diminuir a imunogenicidade do enxerto. O objetivo deste trabalho experimental foi comparar o grau de reparação nervosa, utilizando análise histológica, contagem do número de axônios mielinizados regenerados e análise funcional, obtida com a interposição de enxerto autógeno (grupo A e de tubo de veia glicerolada (grupo B em defeitos de 5 mm no nervo fibular de ratos Wistar. Somente no grupo A foi observado a formação de neuroma. O grupo B apresentou padrões histológicos compatíveis com diminuição quantitativa do número de axônios mielinizados regenerados em menor número em relação ao grupo A (controle. Na recuperação funcional, não houve diferença estatisticamente significativa entre os dois grupos.Autografting is the treatment of choice for cases of major nervous tissue loss where the ruptured nerve ends cannot be reduced. The use of a venous autograft previously treated with glycerol may be an alternative treatment, as it reduces surgery time duration and level of morbidity. Blood vessel explants, used in vascular microsurgery, kept in glycerol maintain their original biological structure, and when used in autografting, present reduced levels of patient's immune response. The aim of this study was to compare the level of nervous tissue regeneration by using histological analysis, regenerated myelinized axons counts, and functional analysis, obtained with the interposition of autologous graft (group A and glycerol-treated vein tube (group B in 5-mm defects on Wistar

  9. Bruxism and prosthetic treatment: a critical review.

    Science.gov (United States)

    Johansson, Anders; Omar, Ridwaan; Carlsson, Gunnar E

    2011-07-01

    Based on the findings from available research on bruxism and prosthetic treatment published in the dental literature, an attempt was made to draw conclusions about the existence of a possible relationship between the two, and its clinical relevance. MEDLINE/PubMed searches were conducted using the terms 'bruxism' and 'prosthetic treatment', as well as combinations of these and related terms. The few studies judged to be relevant were critically reviewed, in addition to papers found during an additional manual search of reference lists within selected articles. Bruxism is a common parafunctional habit, occurring both during sleep and wakefulness. Usually it causes few serious effects, but can do so in some patients. The etiology is multifactorial. There is no known treatment to stop bruxism, including prosthetic treatment. The role of bruxism in the process of tooth wear is unclear, but it is not considered a major cause. As informed by the present critical review, the relationship between bruxism and prosthetic treatment is one that relates mainly to the effect of the former on the latter. Bruxism may be included among the risk factors, and is associated with increased mechanical and/or technical complications in prosthodontic rehabilitation, although it seems not to affect implant survival. When prosthetic intervention is indicated in a patient with bruxism, efforts should be made to reduce the effects of likely heavy occlusal loading on all the components that contribute to prosthetic structural integrity. Failure to do so may indicate earlier failure than is the norm. Copyright © 2011 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  10. Optimising the prescription of prosthetic technologies (opptec): Outcome measures for evidence based prosthetic practice and use

    LENUS (Irish Health Repository)

    Ryall, Dr Nicola

    2010-01-01

    This study provided a forum for patients and service providers to voice their opinions in what they believe to be the important predictors and outcomes involved in successful rehabilitation following limb loss. To develop a consensus on the most important outcomes and factors to address for both the lower limb and upper limb prosthetic prescription process, the above data relating to lower limb and upper prosthetics were subsequently used in the next phase of the research involving two Delphi surveys of 23 and 53 experts within the lower limb and upper limb amputation and prosthetic field respectively, including users, service providers and researchers.\\r\

  11. [Multiple agenesis and prosthetic restoration].

    Science.gov (United States)

    Renault, P

    1990-03-01

    Cases of multiple agenesia present some difficulties in the treatment planing. Three situations may be encountered: limited agenesia, restored by a fixed, bonded or cemented prosthesis, multiple uni- or bimaxillary agenesia without remaining of deciduous teeth, restored by a fixed, bonded or cemented prosthesis or the partial adjacent prosthesis, multiple uni- or bimaxillary agenesia with remaining of deciduous teeth, restored by means of a supra-dental prosthesis. The first two situations have been described in dental literature and are relatively easy to treat. The same is not true for the third situation, where the decision to keep the temporary teeth considerably increases the difficulty of prosthetic restoration. This subject will be illustrated by the presentation of a clinical case of multiple bi-maxillary agenesia. The patient has: on the maxilla: an absence of 9 permanent teeth (18, 15, 14, 12, 22, 23, 24, 25, 28) and the presence of 4 deciduous teeth (62, 63, 64, 65), on the mandible: an absence of all permanent teeth, with the exception of 36 and 46, and the remaining of 4 deciduous teeth (75, 73, 83, 84). The remaining of deciduous teeth and the presence of a very high inter-arch space led to opting for dental coverage so as to keep the deciduous teeth and a proper vertical dimension. The patient wished to solve his "problem" in the maxilla first, and is not wanting to undergo the extraction of his deciduous teeth. The following therapeutic proposal was adapted: On the maxilla, a three-step procedure: first step: building of metal copings on 13, 16 and 26 and metal-ceramic crowns on 11 and 21, second step: building of telescop crowns on 16 and 26 and clasps on 13, 11 and 21, third step: casting of the removable partial denture framework and soldering to the telescop crowns and clasps. On the mandible, a provisional restoration using a supra-dental resin removable partial denture with ceramic occlusal surfaces was adopted. The aesthetic and functional

  12. Mesofluidic controlled robotic or prosthetic finger

    Science.gov (United States)

    Lind, Randall F; Jansen, John F; Love, Lonnie J

    2013-11-19

    A mesofluidic powered robotic and/or prosthetic finger joint includes a first finger section having at least one mesofluidic actuator in fluid communication with a first actuator, a second mesofluidic actuator in fluid communication with a second actuator and a second prosthetic finger section pivotally connected to the first finger section by a joint pivot, wherein the first actuator pivotally cooperates with the second finger to provide a first mechanical advantage relative to the joint point and wherein the second actuator pivotally cooperates with the second finger section to provide a second mechanical advantage relative to the joint point.

  13. Computed Tomography of the complications of prosthetic surgery of the abdominal aorta

    International Nuclear Information System (INIS)

    Giovagnorio, Francesco; Andreoli, Chiara; De Cicco, Maria Luisa

    1997-01-01

    Computerized Tomography has gained an important role in the diagnosis of the complications of prosthetic surgery of the abdominal aorta: the importance of such complications come from their frequency, which is proportional to the increasing number of interventions, and their severity. The authors investigated the CT patterns of the most frequent complications. 24 patients referred for strongly suspected postoperative complications were examined in 2 years: fever and leukocytosis (20 cases) and progressive anemia (4 cases) were the most frequent findings. The operation had been performed 7± 12 weeks before (2 patients were excluded because surgery dated less than 3 weeks. 14 patients had infective complications: thickening (57%) and inhomogeneity (43%) of the periprosthetic wrap and ectopic gas bubble (78%) were the most frequent Computerized Tomography findings. The authors also observed 2 periprosthetic hematomas, 1 aneurysm relapse and 1 prosthetic graft rupture. In conclusion, CT confirmed its important role in the study of the complications of prosthetic aortic surgery, despite its know poor specificity in the demonstration of the aorta in the first 2-3 months postoperatively, in the initial stages of infection and in the diagnosis of aorta-enteric fistulas

  14. Reconstruction of irradiated bone segmental defects with a biomaterial associating MBCP+(R), microstructured collagen membrane and total bone marrow grafting: an experimental study in rabbits.

    Science.gov (United States)

    Jégoux, Franck; Goyenvalle, Eric; Cognet, Ronan; Malard, Olivier; Moreau, Francoise; Daculsi, Guy; Aguado, Eric

    2009-12-15

    The bone tissue engineering models used today are still a long way from any oncologic application as immediate postimplantation irradiation would decrease their osteoinductive potential. The aim of this study was to reconstruct a segmental critical size defect in a weight-bearing bone irradiated after implantation. Six white New Zealand rabbits were immediately implanted with a biomaterial associating resorbable collagen membrane EZ(R) filled and micro-macroporous biphasic calcium phosphate granules (MBCP+(R)). After a daily schedule of radiation delivery, and within 4 weeks, a total autologous bone marrow (BM) graft was injected percutaneously into the center of the implant. All the animals were sacrificed at 16 weeks. Successful osseous colonization was found to have bridged the entire length of the defects. Identical distribution of bone ingrowth and residual ceramics at the different levels of the implant suggests that the BM graft plays an osteoinductive role in the center of the defect. Periosteum-like formation was observed at the periphery, with the collagen membrane most likely playing a role. This model succeeded in bridging a large segmental defect in weight-bearing bone with immediate postimplantation fractionated radiation delivery. This has significant implications for the bone tissue engineering approach to patients with cancer-related bone defects.

  15. Grafting and curing

    International Nuclear Information System (INIS)

    Garnett, J.L.; Loo-Teck Ng; Visay Viengkhou

    1998-01-01

    Progress in radiation grafting and curing is briefly reviewed. The two processes are shown to be mechanistically related. The parameters influencing yields are examined particularly for grafting. For ionising radiation grafting systems (EB and gamma ray) these include solvents, substrate and monomer structure, dose and dose-rate, temperature and more recently role of additives. In addition, for UV grafting, the significance of photoinitiators is discussed. Current applications of radiation grafting and curing are outlined. The recent development of photoinitiator free grafting and curing is examined as well as the potential for the new excimer laser sources. The future application of both grafting and curing is considered, especially the significance of the occurrence of concurrent grafting during cure and its relevance in environmental considerations

  16. Skin graft - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100100.htm Skin graft - series—Normal anatomy To use the sharing features ... entire body, and acts as a protective barrier. Skin grafts may be recommended for: Extensive wounds Burns Specific ...

  17. Autologous alternative veins may not provide better outcomes than prosthetic conduits for below-knee bypass when great saphenous vein is unavailable.

    Science.gov (United States)

    Avgerinos, Efthymios D; Sachdev, Ulka; Naddaf, Abdallah; Doucet, Dannielle R; Mohapatra, Abhisekh; Leers, Steven A; Chaer, Rabih A; Makaroun, Michel S

    2015-08-01

    There is a need to better define the role of alternative autologous vein (AAV) segments over contemporary prosthetic conduits in patients with critical limb ischemia when great saphenous vein (GSV) is not available for use as the bypass conduit. Consecutive patients who underwent bypass to infrageniculate targets between 2007 and 2011 were categorized in three groups: GSV, AAV, and prosthetic. The primary outcome was graft patency. The secondary outcome was limb salvage. Cox proportional hazards regression was used to adjust for baseline confounding variables. A total of 407 infrainguinal bypasses to below-knee targets were analyzed; 255 patients (63%) received a single-segment GSV, 106 patients (26%) received an AAV, and 46 patients (11%) received a prosthetic conduit. Baseline characteristics were similar among groups, with the exception of popliteal targets and anticoagulation use being more frequent in the prosthetic group. Primary patency at 2 and 5 years was estimated at 47% and 32%, respectively, for the GSV group; 24% and 23% for the AAV group; and 43% and 38% for the prosthetic group. Primary assisted patency at 2 and 5 years was estimated at 71% and 55%, respectively, for the GSV group; 53% and 51% for the AAV group; and 45% and 40% for the prosthetic group. Secondary patency at 2 and 5 years was estimated at 75% and 60%, respectively, for the GSV group; 57% and 55% for the AAV group; and 46% and 41% for the prosthetic group. In Cox analysis, primary patency (hazard ratio [HR], 0.55; P < .001; 95% confidence interval [CI], 0.404-0.758), primary assisted patency (HR, 0.57; P = .004; 95% CI, 0.388-0.831), and secondary patency (HR, 0.56; P = .005; 95% CI, 0.372-0.840) were predicted by GSV compared with AAV, but there was no difference between AAV and prosthetic grafts except for the primary patency, for which prosthetic was protective (HR, 0.38; P < .001; 95% CI, 0.224-0.629). Limb salvage was similar among groups. AAV conduits may not offer a significant

  18. Tomographic and echocardiographic diagnosis of mitral prosthetic valve thrombosis

    International Nuclear Information System (INIS)

    Sainz Gonzalez de la Penna, Benito; Ramos Gutierrez, Luis Benito; Gonzalez Artiles, Iovank

    2010-01-01

    Despite the progress achieved in the design of mechanical prosthetic valves, prosthetic valve thrombosis remains a frequent cause of morbidity, usually due to incorrect anticoagulation. A patient was presented with mitral prosthetic thrombosis one year after implantation, who had been diagnosed by transthoracic transesophageal echocardiography imaging and 64-slice computed tomography. Thrombolytic therapy was successful and led to the satisfactory evolution of the patient

  19. Effect of flow on vascular endothelial cells grown in tissue culture on polytetrafluoroethylene grafts

    International Nuclear Information System (INIS)

    Sentissi, J.M.; Ramberg, K.; O'Donnell, T.F. Jr.; Connolly, R.J.; Callow, A.D.

    1986-01-01

    Vascular grafts lined with endothelial cells (EC) grown to confluence in culture before implantation may provide a thromboresistant flow surface. Growth of EC on and their adherence to currently available prosthetic materials under conditions of flow are two impediments remaining in the development of such a graft. To address these problems, 22 polytetrafluoroethylene grafts (PTFE) (5 cm by 4 mm inside diameter) were pretreated with collagen and fibronectin, seeded with 2 to 3 X 10(6) bovine aortic EC per graft, and placed in tissue culture (seeded grafts). Twenty-two grafts pretreated with collagen and fibronectin alone served as controls. After 2 weeks morphologic studies revealed that 20/22 seeded grafts were lined with a confluent endothelial layer. Indium 111-oxine was then used to label the EC-seeded grafts. After exposure to either low (25 ml/min) or high (200 ml/min) flow rates for 60 minutes in an in vitro circuit, examination of the luminal surface of the graft by light microscopy and scanning electron microscopy revealed minimal loss of EC. These findings were corroborated by radionuclide scans that showed an insignificant loss of the EC-associated indium label during exposure to flow (7% low flow, 11% high flow). Pretreatment of PTFE grafts with collagen and fibronectin thus promotes both attachment and adherence of EC even under flow conditions

  20. Transluminal endovascular stent-graft for the treatment of aortic aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Do Yun; Chang, Byung Chul; Shim, Won Heum; Cho, Seung Yun; Chung, Nam Sik; Kwon, Hyuk Moon; Lee, Young Joon; Lee, Jong Tae [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1995-09-15

    The standard treatment for aortic aneurysms is surgical replacement with a prosthetic graft. Currently there is great interest in endoluminal intervention for treatment of aortic aneurysm. The purpose of this study was to evaluate the safety and effectiveness of endoluminally placed Stent-graft for the treatment of aortic aneurysms. Transluminal endovascular Stent-graft placements were attempted in 9 patients with infra-renal aortic aneurysms(n 6), thoracic aortic aneurysm(n = 1), and aortic dissection(n = 2). The endovascular Stent-grafts were custom-designed for each patient and were constructed of self-expandable modified Gianturco Stents covered with polytetrafluroethylene. The Stent-grafts were introduced through a 16-18 French sheath and expanded to 17-30 mm in diameter. The endovascular therapy was performed using a common femoral artery cutdown with local anesthesia. The endovascular Stent-graft deployment was achieved in 7 of 9 patients. Two cases failed deployment of the Stent-graft due to iliac artery stenosis and tortousity. There were complete thrombosis of the thoracic and infra-renal aortic aneurysm surround the Stent-graft in 3 patients, and persistent leak with partial thrombosis in 2. Two patients with aortic dissection were successfully treated by obliteration of entry tears. There were no major complication associated with Stent-graft placement. These preliminary results show that transluminal endovascular Stent-grafts offer great promise and good results. Further investigation is needed to establish its long-term safety and efficacy.

  1. Transluminal endovascular stent-graft for the treatment of aortic aneurysms

    International Nuclear Information System (INIS)

    Lee, Do Yun; Chang, Byung Chul; Shim, Won Heum; Cho, Seung Yun; Chung, Nam Sik; Kwon, Hyuk Moon; Lee, Young Joon; Lee, Jong Tae

    1995-01-01

    The standard treatment for aortic aneurysms is surgical replacement with a prosthetic graft. Currently there is great interest in endoluminal intervention for treatment of aortic aneurysm. The purpose of this study was to evaluate the safety and effectiveness of endoluminally placed Stent-graft for the treatment of aortic aneurysms. Transluminal endovascular Stent-graft placements were attempted in 9 patients with infra-renal aortic aneurysms(n 6), thoracic aortic aneurysm(n = 1), and aortic dissection(n = 2). The endovascular Stent-grafts were custom-designed for each patient and were constructed of self-expandable modified Gianturco Stents covered with polytetrafluroethylene. The Stent-grafts were introduced through a 16-18 French sheath and expanded to 17-30 mm in diameter. The endovascular therapy was performed using a common femoral artery cutdown with local anesthesia. The endovascular Stent-graft deployment was achieved in 7 of 9 patients. Two cases failed deployment of the Stent-graft due to iliac artery stenosis and tortousity. There were complete thrombosis of the thoracic and infra-renal aortic aneurysm surround the Stent-graft in 3 patients, and persistent leak with partial thrombosis in 2. Two patients with aortic dissection were successfully treated by obliteration of entry tears. There were no major complication associated with Stent-graft placement. These preliminary results show that transluminal endovascular Stent-grafts offer great promise and good results. Further investigation is needed to establish its long-term safety and efficacy

  2. Electrospun polydioxanone-elastin blends: potential for bioresorbable vascular grafts

    Energy Technology Data Exchange (ETDEWEB)

    Sell, S A [Virginia Commonwealth University, Richmond, VA 23298 (United States); McClure, M J [Virginia Commonwealth University, Richmond, VA 23298 (United States); Barnes, C P [Virginia Commonwealth University, Richmond, VA 23298 (United States); Knapp, D C [Virginia Commonwealth University, Richmond, VA 23298 (United States); Walpoth, B H [University Hospital, 1211 Geneva 14 (Switzerland); Simpson, D G [Virginia Commonwealth University, Richmond, VA 23298 (United States); Bowlin, G L [Virginia Commonwealth University, Richmond, VA 23298 (United States)

    2006-06-15

    An electrospun cardiovascular graft composed of polydioxanone (PDO) and elastin has been designed and fabricated with mechanical properties to more closely match those of native arterial tissue, while remaining conducive to tissue regeneration. PDO was chosen to provide mechanical integrity to the prosthetic, while elastin provides elasticity and bioactivity (to promote regeneration in vitro/in situ). It is the elastic nature of elastin that dominates the low-strain mechanical response of the vessel to blood flow and prevents pulsatile energy from being dissipated as heat. Uniaxial tensile and suture retention tests were performed on the electrospun grafts to demonstrate the similarities of the mechanical properties between the grafts and native vessel. Dynamic compliance measurements produced values that ranged from 1.2 to 5.6%/100 mmHg for a set of three different mean arterial pressures. Results showed the 50:50 ratio to closely mimic the compliance of native femoral artery, while grafts that contained less elastin exceeded the suture retention strength of native vessel. Preliminary cell culture studies showed the elastin-containing grafts to be bioactive as cells migrated through their full thickness within 7 days, but failed to migrate into pure PDO scaffolds. Electrospinning of the PDO and elastin-blended composite into a conduit for use as a small diameter vascular graft has extreme potential and warrants further investigation as it thus far compares favorably to native vessel.

  3. Alveolar Ridge Contouring with Free Connective Tissue Graft at Implant Placement: A 5-Year Consecutive Clinical Study.

    Science.gov (United States)

    Hanser, Thomas; Khoury, Fouad

    2016-01-01

    This study evaluated volume stability after alveolar ridge contouring with free connective tissue grafts at implant placement in single-tooth gaps. A total of 52 single-tooth gaps with labial volume deficiencies in the maxilla (incisors, canines, and premolars) were consecutively treated with implants and concomitant free palatal connective tissue grafts in 46 patients between 2006 and 2009. Implants had to be covered with at least 2 mm peri-implant local bone after insertion. At implant placement, a free connective tissue graft from the palate was fixed inside a labial split-thickness flap to form an existing concave buccal alveolar ridge contour due to tissue volume deficiency into a convex shape. Standardized volumetric measurements of the labial alveolar contour using a template were evaluated before connective tissue grafting and at 2 weeks, 1 year, and 5 years after implantprosthetic incorporation. Tissue volume had increased significantly (P tissue contour of the implant before connective tissue grafting to baseline (2 weeks after implant-prosthetic incorporation). Statistically, 50% of the reference points (P > .05) kept their volume from baseline to 1 year after prosthetic incorporation and from baseline to 5 years after prosthetic incorporation, respectively, whereas reference points located within the area of the implant sulcus showed a significant (P connective tissue grafting appears to be an appropriate long-term means to contour preexisting buccal alveolar volume deficiencies in single implants.

  4. Bone grafts in dentistry

    Directory of Open Access Journals (Sweden)

    Prasanna Kumar

    2013-01-01

    Full Text Available Bone grafts are used as a filler and scaffold to facilitate bone formation and promote wound healing. These grafts are bioresorbable and have no antigen-antibody reaction. These bone grafts act as a mineral reservoir which induces new bone formation.

  5. Hamster (Mesocricetus auratus cheek pouch as an experimental model to investigate human skin and keloid heterologous graft Bolsa jugal no hamster (Mesocricetus auratus como modelo experimental de investigação de enxertos heterólogos de pele humana e quelóide

    Directory of Open Access Journals (Sweden)

    Bernardo Hochman

    2004-12-01

    Full Text Available To describe the integration process of grafts of total human skin and keloid in hamster (Mesocricetus auratus cheek pouch, whose sub-epithelium is naturally an "Immunologically Privileged Site". Fragments of human normal skin and keloid from the breast region of mulatto female patients were transplanted into the cheek pouch subepithelium in situ. Surgical procedure and grafted pouches for microscopic exam at several time points of the transplantation were standardized. The integration of grafted fragments of human skin and keloid was seen in late periods (84 days since the microscopic assessment showed the presence of blood vases within the conjunctive tissue of grafted fragments. It was also possible to see among the grafted fragments the epithelium, the appearing of early cellular infiltrated, epithelial secretion of keratin, the presence of melanocytes, and delayed changes on the aspect of collagen fibers of conjunctive tissue. Pooled results allow to define hamster cheek pouch sub-epithelium as an experimental model to investigating heterologous graft physiology of human total skin and keloid with epithelium.Descrever a integração dos enxertos de pele total humana e quelóide na bolsa jugal do hamster (Mesocricetus auratus, cujo subepitélio é, naturalmente, um "Local de Privilégio Imunológico". Foram transplantados fragmentos, de pele humana normal e de quelóide, obtidos da região mamária de pacientes pardas, no subepitélio da bolsa jugal in situ. O procedimento operatório, e de preparo das bolsas enxertadas para exame microscópico em vários períodos de transplante, foi padronizado. Verificou-se a integração dos fragmentos enxertados de pele humana e de quelóide em períodos tardios (84 dias, uma vez que a avaliação microscópica revelou a presença de vasos sangüíneos no tecido conjuntivo dos fragmentos enxertados. Foi também possível observar, nos fragmentos enxertados, o epitélio, o aparecimento de infiltrado

  6. Tactile Sensing Reflexes for Advanced Prosthetic Hands

    Science.gov (United States)

    2016-10-01

    Jeremy A. Fishel, Member, IEEE Figure 1. A) Custom NumaTac prosthetic fingertip sensor core and foam; B) Ottobock VariPlus Speed hand installed with two...oal – H ardw are P rototype D evelopm ent R   Identify alternatives for outcom e m easures R   E xplore sensor design param eters C Y16 G oals – C

  7. Prosthetic Management of Patients Presenting with Juvenile ...

    African Journals Online (AJOL)

    Eighteen were referred for prosthetic replacement. Their age ranged between 18 and 36 years. A total of 24 removable partial dentures were fabricated, 17[70.8%] were kennedy class III type, of which 11[64.7%] had the bounded saddle located in the anterior segment. Majority 8[44.4%] of the patients had 2-4 teeth replaced ...

  8. Successful Thrombolysis of Aortic Prosthetic Valve Thrombosis ...

    African Journals Online (AJOL)

    Arun Kumar Agnihotri

    patients with valvular heart disease). Endorsed by the Society of Cardiovascular. Anesthesiologists, Society for Cardiovascular. Angiography and Interventions, and Society of. Thoracic Surgeons. J Am Coll Cardiol. 2008;52(13):e1-142. 5. Elkayam U, Bitar F. Valvular heart disease and pregnancy. Part II: prosthetic valves.

  9. Multimodality Imaging Assessment of Prosthetic Heart Valves

    NARCIS (Netherlands)

    Suchá, D.; Symersky, Petr; Tanis, W; Mali, Willem P Th M; Leiner, Tim; van Herwerden, LA; Budde, Ricardo P J

    Echocardiography and fluoroscopy are the main techniques for prosthetic heart valve (PHV) evaluation, but because of specific limitations they may not identify the morphological substrate or the extent of PHV pathology. Cardiac computed tomography (CT) and magnetic resonance imaging (MRI) have

  10. Consumer satisfaction in prosthetics and orthotics facilities

    NARCIS (Netherlands)

    Geertzen, J.H.B.; Gankema, H.G.J.; Groothoff, J.W.; Dijkstra, P.U.

    The aim of this study was to assess consumer/patient satisfaction with the services of the prosthetics and orthotics (P&O) facilities in the north of the Netherlands, using a modified SERVQUAL questionnaire. In this questionnaire, consumer interests and experiences are assessed on a 5-point Likert

  11. The mechanism of mediated oxidation of carboxylates with ferrocene as redox catalyst in absence of grafting effects. An experimental and theoretical approach

    International Nuclear Information System (INIS)

    Hernández-Muñoz, Lindsay S.; Galano, Annia; Astudillo-Sánchez, Pablo D.; Abu-Omar, Mahdi M.; González, Felipe J.

    2014-01-01

    Graphical abstract: - Highlights: • The mechanism of mediated oxidation of carboxylates. • Thermodynamics of the mediated Kolbe and Non-Kolbe mechanisms. • The oxidation of acetate and diphenylacetate ions by using ferrocene as redox catalyst. • Simulation and DFT calculations of the mediated oxidation of carboxylates. • Radical and carbocationic pathways in the carboxylate oxidation in acetonitrile. - Abstract: The oxidation of tetrabutylammonium carboxylates by using ferrocene derivatives as redox mediators has been recently used to perform the covalent grafting of carbon surfaces with organic and organometallic groups. Due to the intervention of this surface process, a partial description of the reaction mechanism has only been stated. Therefore, this article concerns about two features of the oxidation of carboxylates mediated by ferrocene. In the first part, it is discussed that in the oxidation of acetate ions by using ferrocene as redox catalyst, the gap between both oxidation potentials is very high, which means that the homogeneous electron transfer between the acetate ion and the electrochemically generated ferrocenium ion is energetically unfavorable. However, by using density functional theory calculations, it has been shown that the whole set of coupled chemical reactions involved either in a Kolbe or Non-Kolbe pathway drive the overall mechanisms towards a thermodynamically favorable situation. In order to avoid the strong covalent grafting process that occurs during the mediated oxidation of acetate ions, the second part of this work deals with the oxidation of tetrabutylammonium diphenylacetate by using ferrocene as a redox mediator in acetonitrile on glassy carbon electrodes. With this carboxylate, no electrode inhibition process occurs and, therefore cyclic voltammetry simulation was done to propose the electrochemical and chemical steps that are present when a carboxylate oxidation is performed in the presence of ferrocene derivatives

  12. Pregnancy after Prosthetic Aortic Valve Replacement: How Do We Monitor Prosthetic Valvular Function during Pregnancy?

    Directory of Open Access Journals (Sweden)

    Nicole Sahasrabudhe

    2018-01-01

    Full Text Available Background. With modern medicine, many women after structural heart repair are deciding to experience pregnancy. There is a need for further study to identify normal echocardiographic parameters to better assess prosthetic valvular function in pregnancy. In addition, a multidisciplinary approach is essential in managing pregnant patients with complex cardiac conditions. Case. A 22-year-old nulliparous woman with an aortic valve replacement 18 months prior to her pregnancy presented to prenatal care at 20-week gestation. During her prenatal care, serial echocardiography showed a significant increase in the mean gradient across the prosthetic aortic valve. Multidisciplinary management and a serial echocardiography played an integral role in her care that resulted in a successful spontaneous vaginal delivery without complications. Conclusion. Further characterization of the normal echocardiographic parameters in pregnant patients with prosthetic valves is critical to optimize prenatal care for this patient population. This case report is novel in that serial echocardiograms were obtained throughout prenatal care, which showed significant changes across the prosthetic aortic valve. Teaching Points. (1 Further study is needed to identify normal echocardiographic parameters to best assess prosthetic valvular function in pregnancy. (2 Multidisciplinary management is encouraged to optimize prenatal care for women with prosthetic aortic valve replacements.

  13. Concepção de bancada e montagem de experimento para a análise in vitro de próteses cardíacas mitrais Design conception and experimental setup for in vitro evaluation of mitral prosthetic valves

    Directory of Open Access Journals (Sweden)

    Ovandir Bazan

    2011-06-01

    prosthetic heart valves is due to disturbances of flow, its hydrodynamic characterization is a useful aid in the design of new prostheses. Simulations of pulsatile flow in cardiac prostheses began nearly 40 years ago, through the development of different mock human circulatory systems, improving the clinical results interpretation. A new design of a pulse duplicator system was developed at Polytechnic School of USP to study prosthetic heart valves. OBJECTIVE: To present the conception of a new mock circulatory system for hydrodynamic simulations of cardiac prosthetic valves and the assembly plan of an experiment whose focus is the test of mitral prosthesis. METHODS: Its conception is based on the state-of-art's review of these studies and the experience got with the previous mock circulatory systems, particularly the one used in the Instituto Dante Pazzanese de Cardiologia, São Paulo, SP, Brazil. RESULTS: In this design, an electric servomotor controlled by computer emits, through a hydraulic piston, a pulse to the left ventricular chamber model, where the heart valves are accomodated. To characterize, in the future, the dynamic operation of mitral prosthetic valves, an experimental setup was mounted to provide measurements of volumetric flow, instantaneous pressure and velocity fields on these valves. Optical access is conveniently provided on the design, making possible the use, in the future, of a LDA system. CONCLUSIONS: In order to improve the analysis of hydrodynamic shear stress and prediction of haemolysis, the experimental results may be used to regulate a numerical model using 'Computational Fluid Dynamics' (CFD.

  14. Prosthetic vision: devices, patient outcomes and retinal research.

    Science.gov (United States)

    Hadjinicolaou, Alex E; Meffin, Hamish; Maturana, Matias I; Cloherty, Shaun L; Ibbotson, Michael R

    2015-09-01

    Retinal disease and its associated retinal degeneration can lead to the loss of photoreceptors and therefore, profound blindness. While retinal degeneration destroys the photoreceptors, the neural circuits that convey information from the eye to the brain are sufficiently preserved to make it possible to restore sight using prosthetic devices. Typically, these devices consist of a digital camera and an implantable neurostimulator. The image sensor in a digital camera has the same spatiotopic arrangement as the photoreceptors of the retina. Therefore, it is possible to extract meaningful spatial information from an image and deliver it via an array of stimulating electrodes directly to the surviving retinal circuits. Here, we review the structure and function of normal and degenerate retina. The different approaches to prosthetic implant design are described in the context of human and preclinical trials. In the last section, we review studies of electrical properties of the retina and its response to electrical stimulation. These types of investigation are currently assessing a number of key challenges identified in human trials, including stimulation efficacy, spatial localisation, desensitisation to repetitive stimulation and selective activation of retinal cell populations. © 2015 The Authors. Clinical and Experimental Optometry © 2015 Optometry Australia.

  15. Magnetic Oculomotor Prosthetics for Acquired Nystagmus.

    Science.gov (United States)

    Nachev, Parashkev; Rose, Geoff E; Verity, David H; Manohar, Sanjay G; MacKenzie, Kelly; Adams, Gill; Theodorou, Maria; Pankhurst, Quentin A; Kennard, Christopher

    2017-10-01

    Acquired nystagmus, a highly symptomatic consequence of damage to the substrates of oculomotor control, often is resistant to pharmacotherapy. Although heterogeneous in its neural cause, its expression is unified at the effector-the eye muscles themselves-where physical damping of the oscillation offers an alternative approach. Because direct surgical fixation would immobilize the globe, action at a distance is required to damp the oscillation at the point of fixation, allowing unhindered gaze shifts at other times. Implementing this idea magnetically, herein we describe the successful implantation of a novel magnetic oculomotor prosthesis in a patient. Case report of a pilot, experimental intervention. A 49-year-old man with longstanding, medication-resistant, upbeat nystagmus resulting from a paraneoplastic syndrome caused by stage 2A, grade I, nodular sclerosing Hodgkin's lymphoma. We designed a 2-part, titanium-encased, rare-earth magnet oculomotor prosthesis, powered to damp nystagmus without interfering with the larger forces involved in saccades. Its damping effects were confirmed when applied externally. We proceeded to implant the device in the patient, comparing visual functions and high-resolution oculography before and after implantation and monitoring the patient for more than 4 years after surgery. We recorded Snellen visual acuity before and after intervention, as well as the amplitude, drift velocity, frequency, and intensity of the nystagmus in each eye. The patient reported a clinically significant improvement of 1 line of Snellen acuity (from 6/9 bilaterally to 6/6 on the left and 6/5-2 on the right), reflecting an objectively measured reduction in the amplitude, drift velocity, frequency, and intensity of the nystagmus. These improvements were maintained throughout a follow-up of 4 years and enabled him to return to paid employment. This work opens a new field of implantable therapeutic devices-oculomotor prosthetics-designed to modify eye

  16. Distal vein patch as a form of autologus modification for infragenicular prosthetic bypass.

    Science.gov (United States)

    Totic, Dragan; Rustempasic, Nedzad; Djedovic, Muhamed; Solakovic, Sid; Vukas, Haris; Aslani, Ilijas; Krvavac, Alma; Rudalija, Dzejra; Ahmetasevic, Alen

    2013-01-01

    Preferred graft for infragenicular bypass is autologus vein. The problem is when there is not available autologus vein. Literature suggest that in these situations, prosthetic graft with some form of modification of distal anastomosis with autogenic tissue is valuable adjunctive. Frequently used modifications are Miller's cuff, Taylor's patch and St. Mary's boot. Recently, there are reports on "Distal vein patch" as a form of autologus modification which, due to its simplicity and patency rate, attracted attention. The aim of this study was to evaluate benefits of this novel modification by comparing its patencies with other autologus modification of distal anastomosis. Study was performed on 60 patients, diabetics, with critical limb ischemia (CLI). Patients were divided in two groups: Group with distal vein patch modification; and group with some other form modification - control group. Patients were followed at least 22 months. We examined patency of grafts by physical examination or using Color Doppler. For statistical purposes we used KIaplan Meier analysis and curve. Significance was determined by Mann-Whitney, Fisher's exact, Pearsons chi square or Student T test as appropriate. P value less than 0,05 was considered significant. Groups were fairly matched relative to demographics, risk factors, operative intervention and distal anastomosis site. There was not statistical difference in two year primary patency between distal vein patch and control group--50% vs 53% respectivly (X2 = 0,08; p = 0,773). Also, there was not statistically significant difference in extremity survival (77% vs 77%) and patient survival between groups (89% vs 93%; X2 = 2,458; p = 0,117). This study proved equivalent patencies of infragenicular prosthetic bypasses performed using distal vein patch technique as with any other modification of distal anastomosis.

  17. Mitral Prosthetic Valve Obstruction and Its Complications

    Directory of Open Access Journals (Sweden)

    Rajesh Rajan

    2015-12-01

    Full Text Available Prosthetic Valve Obstruction (PVO is a serious complication which is associated with increased morbidity and mortality. This could result from thrombus formation, development of pannus, or a combination of both. Patients with this complication often present with symptoms and signs of heart failure, systemic embolism, acute cardiovascular collapse, and sudden death. Transesophageal echocardiography and cine fluoroscopy play a vital role in diagnosis of this potentially lethal condition. Herein, we reported a 56-year-old male patient who presented with severe heart failure and was found to have obstructed ATS27 bileaflet mitral prosthetic valve. Thrombolysis and redo surgery are two important options for treating this condition although guidelines for choosing between the two are not very definite.

  18. Prosthetic valve obstruction: Redo surgery or fibrinolysis?

    Directory of Open Access Journals (Sweden)

    Avinash Inamdar

    2017-01-01

    Full Text Available Objective: The aim of this study was to compare the efficacy and safety of surgery versus fibrinolytic therapy in patients with prosthetic valve obstruction. Materials and Methods: We compared 15 patients of prosthetic valve thrombosis treated by surgical line of management and another 15 patients treated by thrombolysis. All patients were initially assessed by clinical evaluation and diagnosis confirmed by transthoracic and transesophageal two-dimensional echocardiography. Depending on hemodynamic stability, pannus, or thrombus on transesophageal echocardiography, the patients were assigned surgical or medical line of management. Results: Patients mortality rate was 40% in fibrinolytic group and 13.33% in surgical group. Recurrence was 40% in fibrinolytic group while there was no recurrence till date in surgery group. Complications were more in fibrinolytic group as opposed to surgery group patient. Conclusion: From our experience, we conclude that redo surgery is effective and definitive treatment, especially in patients with stable hemodynamic conditions.

  19. The radiology of prosthetic heart valves

    International Nuclear Information System (INIS)

    Steiner, R.M.; Flicker, S.

    1985-01-01

    The development of prosthetic heart valves in the late 1950s ushered in a new era in the treatment of heart disease. The radiologist has an important role to play preoperatively in the diagnosis of valvular heart disease. Radiology is valuable in identification of the implanted prosthetic valve and recognition of complications associated with valve implantation. Radiologists must be familiar with the imaging techniques best suited to evaluate the function of the valve prosthesis in question. In this chapter the authors discuss the radiographic approach to the evaluation of the status of patients for valve replacement and the imaging problems peculiar to the types of valves in current use. The relative value of plain-film radiography, fluoroscopy, videorecording and cinerecording, and aortography is addressed, as well as the potential value of magnetic resonance imaging and subsecond dynamic computed tomography

  20. Prosthetic management of an ocular defect

    Directory of Open Access Journals (Sweden)

    Siddesh Kumar Chintal

    2010-01-01

    Full Text Available The disfigurement associated with the loss of an eye can cause significant physical and emotional problems. Various treatment modalities are available, one of which is implants. Although implant has a superior outcome, it may not be advisable in all patients due to economic factors. The present article describes the prosthetic management of an ocular defect with a custom-made ocular prosthesis.

  1. New developments in prosthetic arm systems

    Directory of Open Access Journals (Sweden)

    Vujaklija I

    2016-07-01

    Full Text Available Ivan Vujaklija,1 Dario Farina,1 Oskar C Aszmann2 1Institute of Neurorehabilitation Systems, Bernstein Focus Neurotechnology Göttingen, University Medical Center Göttingen, Georg-August University, Göttingen, Germany; 2Christian Doppler Laboratory for Restoration of Extremity Function, Division of Plastic and Reconstructive Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria Abstract: Absence of an upper limb leads to severe impairments in everyday life, which can further influence the social and mental state. For these reasons, early developments in cosmetic and body-driven prostheses date some centuries ago, and they have been evolving ever since. Following the end of the Second World War, rapid developments in technology resulted in powered myoelectric hand prosthetics. In the years to come, these devices were common on the market, though they still suffered high user abandonment rates. The reasons for rejection were trifold – insufficient functionality of the hardware, fragile design, and cumbersome control. In the last decade, both academia and industry have reached major improvements concerning technical features of upper limb prosthetics and methods for their interfacing and control. Advanced robotic hands are offered by several vendors and research groups, with a variety of active and passive wrist options that can be articulated across several degrees of freedom. Nowadays, elbow joint designs include active solutions with different weight and power options. Control features are getting progressively more sophisticated, offering options for multiple sensor integration and multi-joint articulation. Latest developments in socket designs are capable of facilitating implantable and multiple surface electromyography sensors in both traditional and osseointegration-based systems. Novel surgical techniques in combination with modern, sophisticated hardware are enabling restoration of dexterous upper limb

  2. Control system and method for prosthetic devices

    Science.gov (United States)

    Bozeman, Richard J., Jr. (Inventor)

    1992-01-01

    A control system and method for prosthetic devices is provided. The control system comprises a transducer for receiving movement from a body part for generating a sensing signal associated with that movement. The sensing signal is processed by a linearizer for linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part. The linearized sensing signal is normalized to be a function of the entire range of body part movement from the no-shrug position of the movable body part through the full-shrug position of the movable body part. The normalized signal is divided into a plurality of discrete command signals. The discrete command signals are used by typical converter devices which are in operational association with the prosthetic device. The converter device uses the discrete command signals for driving the movable portions of the prosthetic device and its sub-prosthesis. The method for controlling a prosthetic device associated with the present invention comprises the steps of receiving the movement from the body part, generating a sensing signal in association with the movement of the body part, linearizing the sensing signal to be a linear function of the magnitude of the distance moved by the body part, normalizing the linear signal to be a function of the entire range of the body part movement, dividing the normalized signal into a plurality of discrete command signals, and implementing the plurality of discrete command signals for driving the respective movable prosthesis device and its sub-prosthesis.

  3. Smart Prosthetic Hand Technology - Phase 2

    Science.gov (United States)

    2011-05-01

    functional magnetic resonance imaging (f- MRI ) was used to analyze the reciprocal adaptation between the human brain and the prosthetic hand by the...Schmidt PC. Influence of compacted hydrophobic and hydrophilic colloidal silicon dioxide on tableting properties of pharmaceutical excipients. Drug Dev...nanoparticles, and manganese nanoparticles) in magnetic resonance imaging ( MRI ) in the detection and staging of cancer [2]. 2.1 Iron Oxide

  4. The effect of carbon dioxide therapy on composite graft survival

    OpenAIRE

    Durães, Eliana Ferreira Ribeiro; Durães, Leonardo de Castro; Carneiro, Fabiana Pirani; Lino Júnior, Ruy de Souza; Sousa, João Batista de

    2013-01-01

    PURPOSE: To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. METHODS: An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbon dioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, h...

  5. PVDF multifilament yarns grafted with polystyrene induced by γ-irradiation: Influence of the grafting parameters on the mechanical properties

    International Nuclear Information System (INIS)

    Marmey, P.; Porte, M.C.; Baquey, Ch.

    2003-01-01

    The development of alternative prosthetic materials for cardiovascular applications has found growing interest due to the failure to date to be able to implement functional patent small diameter vascular grafts (diameter <5 mm). For instance, the successful implantation of small diameter polyester (PET) and expanded polytetrafluoroethylene (PTFEe) vascular grafts has not been achieved in humans. Our strategy is to work with a new multifilament yarns biomaterial, produced from polyvinylidene fluoride (PVDF), which shows suitable mechanical properties, such as a lower tensile modulus than PET and PTFEe. The required biological properties sought for (i.e. low thrombogenicity) could be achieved by 'heparin-like' surface modification treatments in order to modify the thrombogenicity levels of the polymeric materials [Ann. Biomed. Eng. 7 (1979) 429]. A four step method is necessary to achieve this 'heparin-like' surface transformation [J. Biomed. Mater. Res. 52 (2000) 119]. The first step consists in grafting polystyrene onto the PVDF surface by γ irradiation. The purpose of this study was to evaluate the influence of grafting parameters on the mechanical properties: (i) γ-ray irradiation time and (ii) grafting time of styrene monomers, which polymerize and form polystyrene bound to the PVDF surface

  6. Mechanical design of a shape memory alloy actuated prosthetic hand.

    Science.gov (United States)

    De Laurentis, Kathryn J; Mavroidis, Constantinos

    2002-01-01

    This paper presents the mechanical design for a new five fingered, twenty degree-of-freedom dexterous hand patterned after human anatomy and actuated by Shape Memory Alloy artificial muscles. Two experimental prototypes of a finger, one fabricated by traditional means and another fabricated by rapid prototyping techniques, are described and used to evaluate the design. An important aspect of the Rapid Prototype technique used here is that this multi-articulated hand will be fabricated in one step, without requiring assembly, while maintaining its desired mobility. The use of Shape Memory Alloy actuators combined with the rapid fabrication of the non-assembly type hand, reduce considerably its weight and fabrication time. Therefore, the focus of this paper is the mechanical design of a dexterous hand that combines Rapid Prototype techniques and smart actuators. The type of robotic hand described in this paper can be utilized for applications requiring low weight, compactness, and dexterity such as prosthetic devices, space and planetary exploration.

  7. Gradual Hunterian ligation for infected prosthetic bypass.

    Science.gov (United States)

    Egun, A; Slade, D; McCollum, C N

    2000-04-01

    To review gradual snare occlusion for the management of complex or recurrent graft infection. Medical records of patients treated with gradual snare occlusion following graft infection were reviewed for indication for operation, type of bypass and graft material used. In addition, infecting organism, grade of infection (Szilágyi) and outcome were recorded. Four femoropopliteal, two extra-anatomic (axillofemoral) and aortobifemoral bypasses were included in this study. All had chronic infection (Szilágyi grade III) with onset of 4 to 24 months and two of which were recurrent. The causative organisms were coagulase-negative staphylococci, Staphylococcus epidermidis and methicillin-resistant Staphylococcus aureus in three patients, with no organism isolated in the remaining cases. There was no loss of limb following gradual snare occlusion but there was only one death due to aortic stump rupture 2 weeks later. Gradual snare occlusion is an alternative for the management of chronic or recurrent graft infection. Copyright 1999 Harcourt Publishers Ltd.

  8. Dynamic elasticity measurement for prosthetic socket design.

    Science.gov (United States)

    Kim, Yujin; Kim, Junghoon; Son, Hyeryon; Choi, Youngjin

    2017-07-01

    The paper proposes a novel apparatus to measure the dynamic elasticity of human limb in order to help the design and fabrication of the personalized prosthetic socket. To take measurements of the dynamic elasticity, the desired force generated as an exponential chirp signal in which the frequency increases and amplitude is maintained according to time progress is applied to human limb and then the skin deformation is recorded, ultimately, to obtain the frequency response of its elasticity. It is referred to as a Dynamic Elasticity Measurement Apparatus (DEMA) in the paper. It has three core components such as linear motor to provide the desired force, loadcell to implement the force feedback control, and potentiometer to record the skin deformation. After measuring the force/deformation and calculating the dynamic elasticity of the limb, it is visualized as 3D color map model of the limb so that the entire dynamic elasticity can be shown at a glance according to the locations and frequencies. For the visualization, the dynamic elasticities measured at specific locations and frequencies are embodied using the color map into 3D limb model acquired by using 3D scanner. To demonstrate the effectiveness, the visualized dynamic elasticities are suggested as outcome of the proposed system, although we do not have any opportunity to apply the proposed system to the amputees. Ultimately, it is expected that the proposed system can be utilized to design and fabricate the personalized prosthetic socket in order for releasing the wearing pain caused by the conventional prosthetic socket.

  9. Adaptive sports technology and biomechanics: prosthetics.

    Science.gov (United States)

    De Luigi, Arthur Jason; Cooper, Rory A

    2014-08-01

    With the technologic advances in medicine and an emphasis on maintaining physical fitness, the population of athletes with impairments is growing. It is incumbent upon health care practitioners to make every effort to inform these individuals of growing and diverse opportunities and to encourage safe exercise and athletic participation through counseling and education. Given the opportunities for participation in sports for persons with a limb deficiency, the demand for new, innovative prosthetic designs is challenging the clinical and technical expertise of the physician and prosthetist. When generating a prosthetic prescription, physicians and prosthetists should consider the needs and preferences of the athlete with limb deficiency, as well as the functional demands of the chosen sporting activity. The intent of this article is to provide information regarding the current advancements in the adaptive sports technology and biomechanics in the field of prosthetics, and to assist clinicians and their patients in facilitating participation in sporting activities. Copyright © 2014 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  10. Long-term engraftment, graft-vs.-host disease, and immunologic reconstitution after experimental transplantation of allogeneic peripheral blood cells from G-CSF-treated donors.

    Science.gov (United States)

    Pan, L; Bressler, S; Cooke, K R; Krenger, W; Karandikar, M; Ferrara, J L

    1996-10-01

    Peripheral blood cells (PBPC) are an alternative source of bone marrow for allogeneic transplantation. Reports from recent clinical trials granulocyte colony-stimulating factor (G-CSF)-mobilized PBPC for allogeneic transplantation show incidence and severity of graft-vs.-host disease (GVHD) similar to those observed in conventional bone marrow transplantation (BMT), despite the presence of 10- to 20-fold more T cell in the PBPC inoculum. In the present study, we examined the effects of pretreatment of donors with G-CSF on GVHD, long-term engraftment, and lymphocyte reconstitution in a murine parent-->F1 model (B6.Ly-5a-->B6d2F1) using splenocytes as a source of peripheral progenitor cells. Recipients of splenocytes from G-CSF-treated donors experienced less mortality from acute GVHD and showed sustained weight gain by day 100 after transplantation. At that time, there was no histological evidence od GVHD in either liver or gut. Recipients of splenocytes from G-CSF-treated donors showed complete donor engraftment within 1 month, which was sustained until the end of the observation period. In contrast, recipients of T cell-depleted splenocytes showed slower donor engraftment and persistent donor/host chimerism. In addition, lymphocyte phenotype and function in mice receiving splenocytes from G-CSF-treated donors was significantly restored by day 100 after transplantation. Thus, the use of G-CSF-mobilized PBPC may provide significant advantages to conventional BMT by reducing GVHD without impairing long-term engraftment and immunologic reconstruction.

  11. Sustained Thromboresistant Bioactivity with Reduced Intimal Hyperplasia of Heparin-Bonded Polytetrafluoroethylene Propaten Graft in a Chronic Canine Femoral Artery Bypass Model.

    Science.gov (United States)

    Freeman, John; Chen, Aaron; Weinberg, Roy J; Okada, Tamuru; Chen, Changyi; Lin, Peter H

    2018-05-01

    Bypass graft thrombosis remains a significant mode of failure in prosthetic graft revascularization. The purpose of this investigation was to evaluate the long-term thromboresistant effect of heparin-bonded expanded polytetrafluoroethylene (ePTFE) graft using Carmeda BioActive Surface technology in a canine model. Bilateral femorofemoral artery bypass grafts with ePTFE grafts were performed in 25 adult grayhound dogs. In each animal, a heparin-bonded ePTFE graft (Propaten, WL Gore) was placed on one side, whereas a control nonheparin graft was placed on the contralateral side. The graft patency was assessed at 1, 6, 12, 18, and 24 months (n = 5 per group) following the bypass. Heparin bioactivity of the graft material was analyzed. The effect of intimal hyperplasia was also assessed. All bypass grafts were patent at 1 month. Significantly greater patency rates were noted in the Propaten group compared to the control group at 12, 18, and 24 months, which were 84%, 80%, and 80% vs. 55%, 35%, and 20%, respectively (P  0.05). Heparin-bonded ePTFE graft provides a thromboresistant surface and reduced anastomotic intimal hyperplasia at 2 years. The stable heparin bioactivity of the Propaten graft confers an advantage in long-term graft patency. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  12. 111In leukocyte scintigraphy in the diagnosis of vascular graft infection

    International Nuclear Information System (INIS)

    Royen, E.A. van; Roevekamp, M.H.; Dongen, R.J.A.M. van; Schoot, J.B. van der; Hardeman, M.R.

    1982-01-01

    Infection at the site of a vascular graft is a serious complication in vascular surgery especially when synthetic materials have been used. Prosthetic grafts are widely employed in aorto-iliac, aorto-femoral and femoro-popliteal bypasses. X-ray investigation, angiography, ultrasound and computer tomography are of limited value in the diagnosis of graft infection. Delay in diagnosis and treatment of this complication results in a high morbidity and mortality. Some reports are available on the use of gallium-67 citrate scintigraphy. However, its accumulation in normal intestinal structures is a serious drawback. The authors investigated the effectiveness of indium-111 leukocytes scintigraphy in the diagnosis of vascular graft infection. The possible accumulation of labelled leukocytes was assessed both subjectively by visual interpretation and quantitatively by computer evaluation. (Auth.)

  13. Osseous scintigraphy and auxiliary graft

    International Nuclear Information System (INIS)

    Khelifa, F.; Siles, S.; Puech, B.

    1992-01-01

    The scintigraphy could be a good way to survey the osseous graft: three cases are studied in which were recognized the presence of a graft, surinfection, graft lysis, pseudo-arthrosis, algodystrophy. 8 refs., 5 figs

  14. Meniscal allograft transplantation. Part 1: systematic review of graft biology, graft shrinkage, graft extrusion, graft sizing, and graft fixation.

    Science.gov (United States)

    Samitier, Gonzalo; Alentorn-Geli, Eduard; Taylor, Dean C; Rill, Brian; Lock, Terrence; Moutzouros, Vasilius; Kolowich, Patricia

    2015-01-01

    To provide a systematic review of the literature regarding five topics in meniscal allograft transplantation: graft biology, shrinkage, extrusion, sizing, and fixation. A systematic literature search was conducted using the PubMed (MEDLINE), ScienceDirect, and EBSCO-CINAHL databases. Articles were classified only in one topic, but information contained could be reported into other topics. Information was classified according to type of study (animal, in vitro human, and in vivo human) and level of evidence (for in vivo human studies). Sixty-two studies were finally included: 30 biology, 3 graft shrinkage, 11 graft extrusion, 17 graft size, and 6 graft fixation (some studies were categorized in more than one topic). These studies corresponded to 22 animal studies, 22 in vitro human studies, and 23 in vivo human studies (7 level II, 10 level III, and 6 level IV). The principal conclusions were as follows: (a) Donor cells decrease after MAT and grafts are repopulated with host cells form synovium; (b) graft preservation alters collagen network (deep freezing) and causes cell apoptosis with loss of viable cells (cryopreservation); (c) graft shrinkage occurs mainly in lyophilized and gamma-irradiated grafts (less with cryopreservation); (d) graft extrusion is common but has no clinical/functional implications; (e) overall, MRI is not superior to plain radiograph for graft sizing; (f) graft width size matching is more important than length size matching; (g) height appears to be the most important factor influencing meniscal size; (h) bone fixation better restores contact mechanics than suture fixation, but there are no differences for pullout strength or functional results; and (i) suture fixation has more risk of graft extrusion compared to bone fixation. Systematic review of level II-IV studies, Level IV.

  15. Vascular complications of prosthetic inter-vertebral discs

    OpenAIRE

    Daly, Kevin J.; Ross, E. Raymond S.; Norris, Heather; McCollum, Charles N.

    2006-01-01

    Five consecutive cases of prosthetic inter-vertebral disc displacement with severe vascular complications on revisional surgery are described. The objective of this case report is to warn spinal surgeons that major vascular complications are likely with anterior displacement of inter-vertebral discs. We have not been able to find a previous report on vascular complications associated with anterior displacement of prosthetic inter-vertebral discs. In all five patients the prosthetic disc had e...

  16. Stiffness and hysteresis properties of some prosthetic feet

    OpenAIRE

    van Jaarsveld, H.W.L.; Grootenboer, H.J.; de Vries, J.; Koopman, Hubertus F.J.M.

    1990-01-01

    A prosthetic foot is an important element of a prosthesis, although it is not always fully recognized that the properties of the foot, along with the prosthetic knee joint and the socket, are in part responsible for the stability and metabolic energy cost during walking. The stiffness and the hysteresis, which are the topics of this paper, are not properly prescribed, but could be adapted to improve the prosthetic walking performance. The shape is strongly related to the cosmetic appearance a...

  17. Improved endothelial cell seeding with cultured cells and fibronectin-coated grafts

    International Nuclear Information System (INIS)

    Seeger, J.M.; Klingman, N.

    1985-01-01

    A possible approach to the low seeding efficiency of endothelial cells into prosthetic grafts is to increase the number of cells to be seeded in cell culture and improve seeding efficiency by graft precoating with fibronectin. The effect of cell culture on cell adhesion is unknown, however, and fibronectin also binds fibrin, which may increase the thrombogenicity of the graft luminal surface. To investigate these questions, freshly harvested canine jugular vein endothelial cells from six animals and similar cells harvested from six primary and eight secondary cell cultures were labeled with 111 Indium and seeded into 5 cm, 4 mm PTFE grafts coated with fibronectin, using similar uncoated PTFE grafts as controls. Platelet accumulation and distribution on six similar coated and uncoated grafts placed in canine carotid, external jugular arterial venous shunts for 2 hr were also determined using autogenous 111 Indium-labeled platelets. Significant differences between group means were determined using the paired Student's t test. Results reveal that seeding efficiency is significantly better in all groups of coated grafts compared to uncoated grafts (P less than 0.01). Cells derived from cell culture also had significantly higher seeding efficiencies than freshly harvested cells when seeded into coated grafts (P less than 0.05) and tended to have higher seeding efficiencies than harvested cells when seeded into uncoated grafts (P = 0.53). Fibronectin coating increased mean platelet accumulation on the entire graft luminal surface, but not to a statistically significant degree (P greater than 0.1). Whether this increased seeding efficiency will improve graft endothelialization remains to be investigated

  18. Fused Filament Fabrication of Prosthetic Components for Trans-Humeral Upper Limb Prosthetics

    Science.gov (United States)

    Lathers, Steven M.

    Presented below is the design and fabrication of prosthetic components consisting of an attachment, tactile sensing, and actuator systems with Fused Filament Fabrication (FFF) technique. The attachment system is a thermoplastic osseointegrated upper limb prosthesis for average adult trans-humeral amputation with mechanical properties greater than upper limb skeletal bone. The prosthetic designed has: a one-step surgical process, large cavities for bone tissue ingrowth, uses a material that has an elastic modulus less than skeletal bone, and can be fabricated on one system. FFF osseointegration screw is an improvement upon the current two-part osseointegrated prosthetics that are composed of a fixture and abutment. The current prosthetic design requires two invasive surgeries for implantation and are made of titanium, which has an elastic modulus greater than bone. An elastic modulus greater than bone causes stress shielding and overtime can cause loosening of the prosthetic. The tactile sensor is a thermoplastic piezo-resistive sensor for daily activities for a prosthetic's feedback system. The tactile sensor is manufactured from a low elastic modulus composite comprising of a compressible thermoplastic elastomer and conductive carbon. Carbon is in graphite form and added in high filler ratios. The printed sensors were compared to sensors that were fabricated in a gravity mold to highlight the difference in FFF sensors to molded sensors. The 3D printed tactile sensor has a thickness and feel similar to human skin, has a simple fabrication technique, can detect forces needed for daily activities, and can be manufactured in to user specific geometries. Lastly, a biomimicking skeletal muscle actuator for prosthetics was developed. The actuator developed is manufactured with Fuse Filament Fabrication using a shape memory polymer composite that has non-linear contractile and passive forces, contractile forces and strains comparable to mammalian skeletal muscle, reaction

  19. Infrascrotal, perineal, femorofemoral bypass for arterial graft infection at the groin.

    Science.gov (United States)

    Illuminati, Giulo; Caliò, Francesco G; D'Urso, Antonio; Giacobbi, Daniela; Papaspyropoulos, Vassilios; Ceccanei, Gianluca

    2004-12-01

    Infrascrotal, perineal, femorofemoral bypass is an acceptable procedure for treating infection of a prosthetic arterial graft limited to a unilateral groin. A consecutive sample clinical study with a mean follow-up of 29 months. The surgical department of an academic tertiary care center and an affiliated secondary care center. Nineteen patients with a mean age of 68 years with prosthetic graft infection at the outflow anastomosis on a femoral artery at the Scarpa triangle underwent an infrascrotal, perineal, femorofemoral bypass, with excision of the graft material limited at the groin. The recipient artery was the profunda femoris artery in 12 cases, the superficial femoral in 5, and the distal common femoral artery in 2. Cumulative survival, recurrence of sepsis, primary graft patency, and limb salvage rates expressed by standard life-table analysis. Postoperative mortality rate was 5%. Cumulative (SE) survival rate was 65% (11.6%) at 3 years. Cumulative (SE) rate of freedom from recurrent sepsis was 88% (8.6%) at 3 years. Cumulative (SE) primary patency and limb salvage rates were 86% (9.4%) and 91% (7.9%), respectively, at 3 years. Femorofemoral bypass with an infrascrotal perineal approach is a valuable procedure for the treatment of femoral arterial graft infection limited at a unilateral groin.

  20. Factors Associated with Prosthetic Looseness in Lower Limb Amputees.

    Science.gov (United States)

    Phonghanyudh, Thong; Sutpasanon, Taweesak; Hathaiareerug, Chanasak; Devakula, M L Buddhibongsa; Kumnerddee, Wipoo

    2015-12-01

    To determine the factors associated with prosthetic looseness in lower limb amputees in Sisaket province. The present was a cross-sectional descriptive study. Subjects were lower limb amputees who previously obtained prostheses and required prosthetic replacements at the mobile prosthetic laboratory unit under the Prostheses Foundation of H.R.H. the Princess Mother at Khun Han Hospital, Sisaket province, in February 2013. Data including participant characteristics, prosthetic looseness data, and various variables were collected by direct semi-structured interview. Energy expenditures in physical activities were measured using the Thai version of the short format international physical activity questionnaire. Data between participants with and without prosthetic looseness were compared to determine prosthetic loosening associated factors. Among 101 participants enrolled, 33 (32.7%) had prosthetic looseness with average onset of 1.76 ± 1.67 years. Diabetes mellitus was the only significant factor associated with prosthetic looseness from both univariate and multivariate analyses (HR = 7.05, p = 0.002 and HR = 5.93, p = 0.007 respectively). Among the lower limb amputees in Sisaket province, diabetes mellitus was the only factor associated with prosthetic looseness. Therefore, diabetic screening should be supplemented in lower limb amputee assessment protocol. In addition, we recommend that amputees with diabetes mellitus should receive prosthesis check out at approximately

  1. Echocardiographic Evaluation of Tricuspid Prosthetic Valves: An Update

    Directory of Open Access Journals (Sweden)

    Dimitrios Maragiannis, MD, FASE, FACC

    2016-05-01

    Full Text Available This review focuses on the diagnostic value of novel echocardiographic techniques and the clinical application of recently described algorithms to assess tricuspid prosthetic valve function.

  2. The role of osteoblasts in peri-prosthetic osteolysis.

    LENUS (Irish Health Repository)

    O'Neill, S C

    2013-08-01

    Peri-prosthetic osteolysis and subsequent aseptic loosening is the most common reason for revising total hip replacements. Wear particles originating from the prosthetic components interact with multiple cell types in the peri-prosthetic region resulting in an inflammatory process that ultimately leads to peri-prosthetic bone loss. These cells include macrophages, osteoclasts, osteoblasts and fibroblasts. The majority of research in peri-prosthetic osteolysis has concentrated on the role played by osteoclasts and macrophages. The purpose of this review is to assess the role of the osteoblast in peri-prosthetic osteolysis. In peri-prosthetic osteolysis, wear particles may affect osteoblasts and contribute to the osteolytic process by two mechanisms. First, particles and metallic ions have been shown to inhibit the osteoblast in terms of its ability to secrete mineralised bone matrix, by reducing calcium deposition, alkaline phosphatase activity and its ability to proliferate. Secondly, particles and metallic ions have been shown to stimulate osteoblasts to produce pro inflammatory mediators in vitro. In vivo, these mediators have the potential to attract pro-inflammatory cells to the peri-prosthetic area and stimulate osteoclasts to absorb bone. Further research is needed to fully define the role of the osteoblast in peri-prosthetic osteolysis and to explore its potential role as a therapeutic target in this condition.

  3. Prosthetic hip joint infection due to Campylobacter fetus.

    OpenAIRE

    Bates, C J; Clarke, T C; Spencer, R C

    1994-01-01

    A case of postoperative prosthetic hip joint infection due to Campylobacter fetus subsp. fetus is described. Difficulties in isolation and antimicrobial susceptibility testing of this organism are discussed.

  4. Successful Management of Prosthetic Valve Brucella Endocarditis with Antibiotherapy Alone

    Directory of Open Access Journals (Sweden)

    José Pedro Fonseca

    2018-01-01

    Full Text Available Objectives: To report a case of mechanical aortic prosthesis Brucella endocarditis successfully treated with antibiotics alone. Materials and methods: We describe a clinical case and present a review of the literature. Results: A 60-year-old female farmer with a mechanical aortic prosthetic valve presented with low back pain and fever. She was diagnosed with prosthetic valve Brucella mellitensis endocarditis and was cured with antibiotic therapy alone. Few cases of successfully treated prosthetic valve Brucella endocarditis without surgery have been reported. Conclusion: Prosthetic valve Brucella endocarditis usually requires surgical valve replacement. However, selected patients may be successfully treated with antibiotic therapy alone.

  5. An experimental model for the surgical correction of tracheomalacia.

    Science.gov (United States)

    Shaha, A R; Burnett, C; DiMaio, T; Jaffe, B M

    1991-10-01

    Tracheomalacia may result from large intrathoracic goiters. Due to the chronic compression, particularly within the confines of the thoracic inlet, the tracheal wall weakens, with disintegration of some of the cartilaginous rings. Tracheomalacia can cause acute airway distress, particularly during the post-operative period, and may occasionally result in death. The other major cause of tracheomalacia is related to either prolonged endotracheal intubation or over-inflation of the tracheostomy cuff. While various techniques such as internal stenting, external support devices, tracheostomy, and tracheal resection have been used based on individual circumstances, no one method appears to be perfect. To further study this difficult problem, an experimental model of tracheomalacia was created in eight dogs. Six to seven rings of the tracheal cartilages were dissected submucosally. More than half of the circumference of the tracheal rings was resected. The tracheal walls were reconstructed with polytetrafluoroethylene (PTFE) grafts. The grafts strengthened the tracheal wall without causing luminal constriction. Tracheostomy was not performed on any of the dogs. All dogs tolerated the procedure well and were extubated at the conclusion of the experiment. The dogs were followed for 4 to 6 months and then sacrificed so that the tracheal wall could be examined histologically. There was considerable fibrosis leading to stiff neotrachea. The results of this experimental technique for prosthetic reconstruction to counteract problems simulating tracheomalacia are very encouraging.

  6. Advances in radiation grafting

    International Nuclear Information System (INIS)

    Hegazy, El-Sayed A.; AbdEl-Rehim, H.A.; Kamal, H.; Kandeel, K.A.

    2001-01-01

    Graft copolymerization is an attractive means for modifying base polymers because grafting frequently results in the superposition of properties relating to the backbone and pendent chains. Among the various methods for initiating the grafting reaction, ionizing radiation is the cleanest and most versatile method of grafting available. Ion-exchange membranes play an important role in modern technology, especially in separation and purification of materials. The search for improved membrane composition has considered almost every available polymeric material because of its great practical importance. Grafting of polymers with a mixture of monomers is important since different types of chains containing different functional groups are included. A great deal is focused on the waste treatment of heavy and toxic metals from wastewater because of the severe problems of environmental pollution. Functionalized polymers suitable for metal adsorption with their reactive functional groups such as carboxylic and pyridine groups suitable for waste treatment were prepared by radiation grafting method. More reactive chelating groups were further introduced to the grafted copolymer through its functional groups by chemical treatments with suitable reagents. The advances of radiation grafting and possible uses are briefly discussed

  7. Bone graft revascularization strategies

    NARCIS (Netherlands)

    Willems, W.F.

    2014-01-01

    Reconstruction of avascular necrotic bone by pedicled bone grafting is a well-known treatment with little basic research supporting its application. A new canine model was used to simulate carpal bone avascular necrosis. Pedicled bone grafting proved to increase bone remodeling and bone blood flow,

  8. The effect of carbon dioxide therapy on composite graft survival.

    Science.gov (United States)

    Durães, Eliana Ferreira Ribeiro; Durães, Leonardo de Castro; Carneiro, Fabiana Pirani; Lino, Ruy de Souza; Sousa, João Batista de

    2013-08-01

    To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbon dioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, histopathology features and histomorphometry of collagen. The treated group had a significantly lower weight gain (p=0.038). Histopathology was not significantly different between groups. There was an increase in amount of collagen in 2 cm grafts submitted to carbon dioxide therapy (p=0.003). Carboxytherapy didn't influence graft survival rate for 1.5 cm grafts or 2 cm grafts (p=0.567 and p=0.777, respectively). Carbon dioxide therapy increased the amount of collagen in 2 cm grafts. CO2 was not significantly different from saline infusion on composite grafts survival, but this study suggests that there is a mechanical effect caused by distension which favored graft survival.

  9. GRAFT TAKES OF TOMATO ON OTHER SOLANACEOUS PLANTS

    Directory of Open Access Journals (Sweden)

    ANDRÉ RICARDO ZEIST

    2017-01-01

    Full Text Available This paper aimed to assess tomato grafting on different solanaceous species through two grafting methods. Scions were cut from cultivar Santa Cruz Kada seedlings. A fully randomized experimental design was carried out with treatments in a 9 x 2 factorial scheme. As rootstocks, four accessions of mini - tomatoes (0224 - 53, RVTC 57, RVTC 20 and 6889 - 50 - Solanum lycopersicum L; two species of wild tomato ( Solanum habrochaites var hirsutum ‘PI - 127826’ and Solanum pennellii ‘LA716’; other two tomato species [ Solanum, cocona ( Solanum sessiliflorum and physalis ( Physalis peruviana ] and a control with cultivar Santa Cruz Kada (auto - graft rootstocks were used. In addition, two grafting methods were evaluated full cleft and approach graft. Fifteen days after grafting, plants were assessed for graft - take percentage; root length; plant height; leaf number; foliar area; root, stem and leaf dry matter; and ratio between shoot and root dry matter. Based on the results, we may state rootstock and grafting interaction had effect on both graft - take rate and plant development. Overall, the studied plants should be recommended as rootstock, except for 6889 - 50 mini - tomato ( S. lycopersicum L. and S. pennellii . Full cleft grafting was most suitable for cocona and physalis, while the approach method showed better results for the mini - tomato accessions 0224 - 53, RVTC 57 and RVTC 20, as well as for S. habrochaites .

  10. Pre prosthetic reconstruction of alveolar ridge

    Directory of Open Access Journals (Sweden)

    Prabhuji Munivenkatappa Lakshmaiahenkatesh

    2011-01-01

    Full Text Available Dento-alveolar bony defects are common and occur due to a variety of causes, such as, pulpal pathology, traumatic tooth extraction, advanced periodontal disease, implant failure, tumor or congenital anomalies. These defects often cause a significant problem in dental treatment and rehabilitation. Many techniques exist for effective soft and hard tissue augmentation. The approach is largely based on the extent of the defect and specific procedures to be performed for the implant or prosthetic rehabilitation. This article presents case reports of soft and hard tissue ridge augmentation.

  11. Prevention of Infection in Orthopedic Prosthetic Surgery.

    Science.gov (United States)

    Chirca, Ioana; Marculescu, Camelia

    2017-06-01

    Total joint arthroplasty is a generally safe orthopedic procedure; however, infection is a potentially devastating complication. Multiple risk factors have been identified for development of prosthetic joint infections. Identification of patients at risk and preoperative correction of known risk factors, such as smoking, diabetes mellitus, anemia, malnutrition, and decolonization of Staphylococcus carriers, represent well-established actions to decrease the infection risk. Careful operative technique, proper draping and skin preparation, and appropriate selection and dosing of antimicrobials for perioperative prophylaxis are also very important in prevention of infection. Published by Elsevier Inc.

  12. GRAFT COPOLYMERIZATION OF OLYGOESTERACRYLATES WITH LIQUID RUBBER AND COPOLYMER’S CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    Y. A. Anisimov

    2015-02-01

    Full Text Available The kinetic of graft copolymerization of threeethyleneglicoldimethacrylate and di threeethyleneglicolftalatedimethacrylate with liquid buthadiene rubber have been studied as a function of the olygomers composition. The experimental constants of copolymerization rate and efficiency olygoesteracrylates graft to liquid rubber were determined. The ihfluence of olygoesteracrylates’ nature on the grafting efficiency to olygomer rubber is determined and the strength characteristics are found.

  13. Prosthetic Rehabilitation in Children: An Alternative Clinical Technique

    Directory of Open Access Journals (Sweden)

    Nádia Carolina Teixeira Marques

    2013-01-01

    Full Text Available Complete and partial removable dentures have been used successfully in numerous patients with oligodontia and/or anodontia. However, there is little information in the literature regarding the principles and guidelines to prosthetic rehabilitation for growing children. This case report describes the management of a young child with oligodontia as well as the treatment planning and the prosthetic rehabilitation technique.

  14. 21 CFR 890.3025 - Prosthetic and orthotic accessory.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3025... intended for medical purposes to support, protect, or aid in the use of a cast, orthosis (brace), or prosthesis. Examples of prosthetic and orthotic accessories include the following: A pelvic support band and...

  15. Successful thrombolysis of aortic prosthetic valve thrombosis during ...

    African Journals Online (AJOL)

    Successful thrombolysis of aortic prosthetic valve thrombosis during first trimester of pregnancy. A Shukla, AP Raval, R Shah. Abstract. Prosthetic heart valve thrombosis during pregnancy is life-threatening. Standard surgical treatment using cardiopulmonary bypass carries high maternal and fetal complications. Here we ...

  16. Stiffness and hysteresis properties of some prosthetic feet

    NARCIS (Netherlands)

    van Jaarsveld, H.W.L.; Grootenboer, H.J.; de Vries, J.; Koopman, Hubertus F.J.M.

    1990-01-01

    A prosthetic foot is an important element of a prosthesis, although it is not always fully recognized that the properties of the foot, along with the prosthetic knee joint and the socket, are in part responsible for the stability and metabolic energy cost during walking. The stiffness and the

  17. Prosthetic prescription in the Netherlands: An interview with clinical experts

    NARCIS (Netherlands)

    Van Der Linde, H.; Geertzen, J.H.B.; Hofstad, C.J.; Van Limbeek, Jacques; Postema, K.

    2004-01-01

    In the process of guideline development for prosthetic prescription in the Netherlands the authors made a study of the daily clinical practice of lower limb prosthetics. Besides the evidence-based knowledge from literature the more implicit knowledge from clinical experts is of importance for

  18. 38 CFR 17.150 - Prosthetic and similar appliances.

    Science.gov (United States)

    2010-07-01

    ... appliances. 17.150 Section 17.150 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS MEDICAL Prosthetic, Sensory, and Rehabilitative Aids § 17.150 Prosthetic and similar appliances... appliances including invalid lifts and therapeutic and rehabilitative devices, and special clothing made...

  19. Expression of bone morphogenic protein 2/4, transforming growth factor-β1, and bone matrix protein expression in healing area between vascular tibia grafts and irradiated bone-experimental model of osteonecrosis

    International Nuclear Information System (INIS)

    Schultze-Mosgau, Stefan; Lehner, Bernhard; Roedel, Franz; Wehrhan, Falk; Amann, Kerstin; Kopp, Juergen; Thorwarth, Michael; Nkenke, Emeka; Grabenbauer, Gerhard

    2005-01-01

    Purpose: For the surgical treatment of osteoradionecrosis after multimodal therapy of head-and-neck cancers, free vascular bone grafts are used to reconstruct osseous structures in the previously irradiated graft bed. Reduced, or even absent osseous healing in the transition area between the vascular graft and the irradiated graft bed represents a clinical problem. Inflammatory changes and fibrosis lead to delayed healing, triggered by bone morphogentic protein 2/4 (BMP2/4) and transforming growth factor (TGF)-β 1 . Given the well-known fibrosis-inducing activity of TGF-β 1 , an osteoinductive effect has been reported for BMP2/4. However, the influence of irradiation (RT) on this cytokine expression remains elusive. Therefore, the aim of the present in vivo study was to analyze the expression of BMP2/4, TGF-β 1 , collagen I, and osteocalcin in the transition area between the bone graft and the graft bed after RT. Methods and materials: Twenty Wistar rats (male, weight 300-500 g) were used in this study. A free vascular tibia graft was removed in all rats and maintained pedicled in the groin region. Ten rats underwent RT with 5 x 10 Gy to the right tibia, the remainder served as controls. After 4 weeks, the previously removed tibia grafts were regrafted into the irradiated (Group 1) and nonirradiated (Group 2) graft beds. The interval between RT and grafting was 4 weeks. After a 4-week osseous healing period, the bone grafts were removed, and the transition area between the nonirradiated graft and the irradiated osseous graft bed was examined histomorphometrically (National Institutes of Health imaging program) and immunohistochemically (avidin-biotin-peroxidase complex) for the expression of BMP2/4, TGF-β 1 , collagen I, and osteocalcin. Results: Absent or incomplete osseous healing of the graft was found in 9 of 10 rats after RT with 50 Gy and in 1 of 10 of the rats with nonirradiated osseous grafts. Histomorphometrically, the proportion of osseous healing in

  20. Review of Prosthetic Joint Infection from Listeria monocytogenes.

    Science.gov (United States)

    Bader, Gilbert; Al-Tarawneh, Mohammed; Myers, James

    2016-12-01

    Prosthetic joint infection from Listeria monocytogenes is rare. We decided to shed light on this illness and review the reported cases to better understand its characteristics. We conducted a comprehensive review of the English literature using PubMed. We also included one case that we had managed. We found 25 cases of prosthetic joint infection from L. monocytogenes reported individually and a retrospective study of 43 cases of joint and bone listerial infection, including 34 with prosthetic joint infection, conducted in France. We have described their clinical and para-clinical features and tried to elaborate on the pathophysiology, treatment, and prevention. Prosthetic joint infection from L. monocytogenes is mainly late. Systemic inflammation may be absent. Although rare, it must be suspected in patients at high risk for both prosthetic joint and listerial infections. In addition, those patients must be instructed on appropriate preventive measures.

  1. Nitinol for Prosthetic and Orthotic Applications

    Science.gov (United States)

    Henderson, Emma; Buis, Arjan

    2011-07-01

    As global populations age, conditions such as stroke and diabetes require individuals to use rehabilitation technology for many years to come due to chronic musculoskeletal, sensory, and other physical impairments. One in four males currently aged 45 will experience a stroke within 40 years and will often require access to prolonged rehabilitation. In addition, worldwide, one individual loses a limb every 30 s due to the complications of diabetes. As a result, innovative ideas are required to devise more effective prosthetic and orthotic devices to enhance quality of life. While Nitinol has already found much favor within the biomedical industry, one area, which has not yet exploited its unique properties, is in the field of physical rehabilitation, ranging from prosthetic and orthotic devices to assistive technology such as wheelchairs. Improved intervention capabilities based on materials such as Nitinol have the potential to vastly improve patients' quality of life and in the case of orthoses, may even reduce the severity of the condition over time. It is hoped that this study will spark discussion and interest for the materials community in a field which has yet to be fully exploited.

  2. Is the Prosthetic Homologue Necessary for Embodiment?

    Science.gov (United States)

    Dornfeld, Chelsea; Swanston, Michelle; Cassella, Joseph; Beasley, Casey; Green, Jacob; Moshayev, Yonatan; Wininger, Michael

    2016-01-01

    Embodiment is the process by which patients with limb loss come to accept their peripheral device as a natural extension of self. However, there is little guidance as to how exacting the prosthesis must be in order for embodiment to take place: is it necessary for the prosthetic hand to look just like the absent hand? Here, we describe a protocol for testing whether an individual would select a hand that looks like their own from among a selection of five hands, and whether the hand selection (regardless of homology) is consistent across multiple exposures to the same (but reordered) set of candidate hands. Pilot results using healthy volunteers reveals that hand selection is only modestly consistent, and that selection of the prosthetic homologue is atypical (61 of 192 total exposures). Our protocol can be executed in minutes, and makes use of readily available equipment and softwares. We present both a face-to-face and a virtual protocol, for maximum flexibility of implementation.

  3. The Prosthetic Workflow in the Digital Era

    Directory of Open Access Journals (Sweden)

    Lidia Tordiglione

    2016-01-01

    Full Text Available The purpose of this retrospective study was to clinically evaluate the benefits of adopting a full digital workflow for the implementation of fixed prosthetic restorations on natural teeth. To evaluate the effectiveness of these protocols, treatment plans were drawn up for 15 patients requiring rehabilitation of one or more natural teeth. All the dental impressions were taken using a Planmeca PlanScan® (Planmeca OY, Helsinki, Finland intraoral scanner, which provided digital casts on which the restorations were digitally designed using Exocad® (Exocad GmbH, Germany, 2010 software and fabricated by CAM processing on 5-axis milling machines. A total of 28 single crowns were made from monolithic zirconia, 12 vestibular veneers from lithium disilicate, and 4 three-quarter vestibular veneers with palatal extension. While the restorations were applied, the authors could clinically appreciate the excellent match between the digitally produced prosthetic design and the cemented prostheses, which never required any occlusal or proximal adjustment. Out of all the restorations applied, only one exhibited premature failure and was replaced with no other complications or need for further scanning. From the clinical experience gained using a full digital workflow, the authors can confirm that these work processes enable the fabrication of clinically reliable restorations, with all the benefits that digital methods bring to the dentist, the dental laboratory, and the patient.

  4. Comparison of FLIXENE™ and standard PTFE arteriovenous graft for early haemodialysis.

    Science.gov (United States)

    Chiang, Nathaniel; Hulme, Katherine Ria; Haggart, Paul Charles; Vasudevan, Thodur

    2014-01-01

    The purpose is to compare the outcomes of FLIXENE™ arteriovenous graft (AVG) to standard polytetrafluoroethylene (PTFE) AVG for early haemodialysis. This is a prospective observational study of all AVGs placed over a 40-month period between 2008 and 2011 at our vascular unit. Primary outcome was to examine early cannulation rates for FLIXENE™. Secondary outcomes included patency rates, usability of grafts, complications in particular infections, interventions and death in comparison to standard PTFE grafts. Forty-five FLIXENE™ and 19 standard PTFE AVGs were placed in the study period; 89% of FLIXENE™ grafts were used for dialysis, with 78% cannulated within 3 days. At 18 months, primary patency (FLIXENE™ 34% vs standard PTFE 24%), primary assisted patency (35% vs 36%) and secondary patency rate (51% vs 48%) were not statistically different; 20.2% of FLIXENE™ grafts were infected at 18 months requiring explantation compared with 40.3% of standard PTFE grafts (p=0.14). FLIXENE™ can be cannulated for dialysis within 3 days. It has similar patency and complication rates as other prosthetic grafts in the market. In patients who have no access and require urgent dialysis, FLIXENE™ is a viable option.

  5. Aging and its impact onthe quality of grafts: an experimental study in rats livers O impacto do envelhecimento na qualidade do enxerto: estudo experimental em fígados de ratos

    Directory of Open Access Journals (Sweden)

    Stela Maria Mota

    2010-09-01

    Full Text Available CONTEXT: There are consistent clues of worse results with grafts from older donors, especially in hepatitis C. University of Wisconsin (UW solution is adopted for liver preservation, but other solutions are being studied, as fructose-1,6-bisphosphate (FBP. OBJECTIVE: To determinate the impact of aging of the donor on the cold ischemia injury in rat livers and compare UW and FBP. METHODS: Twenty male Wistar rats were studied - 10, aging 20 weeks: 5 to preservation with UW (C-UW and 5, FBP (C-FBP; and other 10, aging 50 weeks: 5 to UW (E-UW and 5 to FBP (E-FBP. Rats were anesthesized, submitted to hepatectomy, and graft was kept under 2-4ºC for 8 hours. Liquid samples were taken at 2, 4, 6, and 8 hours, to determine AST and LDH. At the end, in the liver tissue thiobarbituric acid reactive substances and catalase were determined. RESULTS: Average liver weight was similar between controls and the others (12.5 g ± 1.8 and 13.4 g ± 2.0. AST and LDH levels were higher in C-UW group (PCONTEXTO: Dados da literatura atual sugerem piores resultados quando os transplantes hepáticos são realizados com enxertos provenientes de doadores idosos. O uso da solução Universidade de Wisconsin (UW é universal; entretanto alternativas como a fructose-1,6-bisfosfato (FBP vêm sendo estudadas. OBJETIVOS: Determinar o impacto do envelhecimento do doador no dano de isquemia a frio em fígados de ratos, comparando as soluções de FBP e UW. MÉTODOS: Vinte ratos Wistar foram estudados - 10 com 20 semanas: 5 preservados com UW (C-UW e 5 com FBP (C-FBP; e outros 10, com 50 semanas: 5 com UW (E-UW e 5 com FBP (E-FBP. A preservação durou 8 horas. Foram dosadas AST e LDH nas alíquotas do líquido de preservação a cada 2 horas. RESULTADOS: Os níveis de AST e LDH foram superiores no grupo (C-UW (P<0.05. Quando comparadas UW x FBP no grupo de idosos houve diferença quanto à LDH, mas não com a AST. CONCLUSÃO: A preservação dos fígados de ratos idosos foi

  6. Tissue response and wound healing after placement of two types of bioengineered grafts containing vital cells in submucosal maxillary pouches: an experimental pilot study in rabbits.

    Science.gov (United States)

    Bornstein, Michael M; Reichart, Peter A; Buser, Daniel; Bosshardt, Dieter D

    2011-01-01

    This pilot study evaluated the wound healing and tissue response after placement of two different skin substitutes in subgingival mucosal pouches in rabbits. Four rabbits were selected to receive a commercially available skin substitute consisting of a collagen matrix with fibroblasts and an epithelial layer (test membrane 1) and a prototype device consisting of a collagen matrix with fibroblasts only (test membrane 2). In each rabbit, two horizontal incisions were made in the buccal alveolar mucosa of the maxilla bilaterally to create submucosal pouches. Three pouches in each animal were filled with either the test 1 or test 2 membranes, and one pouch was left without a membrane (sham-operated control). All rabbits were sacrificed after a healing period of 4 weeks, and histologic samples were prepared and examined. After a healing period of 1 month, both tested membranes were still visible in the sections. Test membrane 1 was still bilayered, contained inflammatory cells in its center, and was encapsulated by a thick fibrous tissue. Numerous ectopic calcifications were evident in the collagenous part of the membrane and in association with some basal epithelial cells. Test membrane 2 was also encapsulated in fibrous tissue, with inflammatory cells present only between the fibrous encapsulation and the remnants of the membrane. For test membrane 2, no calcifications were visible. Test membrane 1 seemed to be more resistant to degradation, but there was also a more pronounced inflammatory reaction in comparison to test membrane 2, especially in the vicinity of the keratinocytes. The significance of the ectopic calcifications, along with that of the resorption or degradation processes of both tested membranes, must be evaluated in future experimental studies, with different time points after implantation examined.

  7. Prosthetic finger phalanges with lifelike skin compliance for low-force social touching interactions

    Directory of Open Access Journals (Sweden)

    Ge Shuzhi

    2011-03-01

    Full Text Available Abstract Background Prosthetic arms and hands that can be controlled by the user's electromyography (EMG signals are emerging. Eventually, these advanced prosthetic devices will be expected to touch and be touched by other people. As realistic as they may look, the currently available prosthetic hands have physical properties that are still far from the characteristics of human skins because they are much stiffer. In this paper, different configurations of synthetic finger phalanges have been investigated for their skin compliance behaviour and have been compared with the phalanges of the human fingers and a phalanx from a commercially available prosthetic hand. Methods Handshake tests were performed to identify which areas on the human hand experience high contact forces. After these areas were determined, experiments were done on selected areas using an indenting probe to obtain the force-displacement curves. Finite element simulations were used to compare the force-displacement results of the synthetic finger phalanx designs with that of the experimental results from the human and prosthetic finger phalanges. The simulation models were used to investigate the effects of (a varying the internal topology of the finger phalanx and (b varying different materials for the internal and external layers. Results and Conclusions During handshake, the high magnitudes of contact forces were observed at the areas where the full grasping enclosure of the other person's hand can be achieved. From these areas, the middle phalanges of the (a little, (b ring, and (c middle fingers were selected. The indentation experiments on these areas showed that a 2 N force corresponds to skin tissue displacements of more than 2 mm. The results from the simulation model show that introducing an open pocket with 2 mm height on the internal structure of synthetic finger phalanges increased the skin compliance of the silicone material to 235% and the polyurethane material to

  8. Passive prosthetic hands and tools: A literature review.

    Science.gov (United States)

    Maat, Bartjan; Smit, Gerwin; Plettenburg, Dick; Breedveld, Paul

    2018-02-01

    The group of passive prostheses consists of prosthetic hands and prosthetic tools. These can either be static or adjustable. Limited research and development on passive prostheses has been performed although many people use these prosthesis types. Although some publications describe passive prostheses, no recent review of the peer-reviewed literature on passive prostheses is available. Review the peer-reviewed literature on passive prostheses for replacement of the hand. Literature review. Four electronic databases were searched using a Boolean combination of relevant keywords. English-language articles relevant to the objective were selected. In all, 38 papers were included in the review. Publications on passive prosthetic hands describe their users, usage, functionality, and problems in activities of daily living. Publications on prosthetic tools mostly focus on sport, recreation, and vehicle driving. Passive hand prostheses receive little attention in prosthetic research and literature. Yet one out of three people with a limb deficiency uses this type of prosthesis. Literature indicates that passive prostheses can be improved on pulling and grasping functions. In the literature, ambiguous names are used for different types of passive prostheses. This causes confusion. We present a new and clear classification of passive prostheses. Clinical relevance This review provides information on the users of passive prosthetic hands and tools, their usage and the functionality. Passive prostheses receive very little attention and low appreciation in literature. Passive prosthetic hands and tools show to be useful to many unilateral amputees and should receive more attention and higher acceptance.

  9. Viability of Controlling Prosthetic Hand Utilizing Electroencephalograph (EEG) Dataset Signal

    Science.gov (United States)

    Miskon, Azizi; A/L Thanakodi, Suresh; Raihan Mazlan, Mohd; Mohd Haziq Azhar, Satria; Nooraya Mohd Tawil, Siti

    2016-11-01

    This project presents the development of an artificial hand controlled by Electroencephalograph (EEG) signal datasets for the prosthetic application. The EEG signal datasets were used as to improvise the way to control the prosthetic hand compared to the Electromyograph (EMG). The EMG has disadvantages to a person, who has not used the muscle for a long time and also to person with degenerative issues due to age factor. Thus, the EEG datasets found to be an alternative for EMG. The datasets used in this work were taken from Brain Computer Interface (BCI) Project. The datasets were already classified for open, close and combined movement operations. It served the purpose as an input to control the prosthetic hand by using an Interface system between Microsoft Visual Studio and Arduino. The obtained results reveal the prosthetic hand to be more efficient and faster in response to the EEG datasets with an additional LiPo (Lithium Polymer) battery attached to the prosthetic. Some limitations were also identified in terms of the hand movements, weight of the prosthetic, and the suggestions to improve were concluded in this paper. Overall, the objective of this paper were achieved when the prosthetic hand found to be feasible in operation utilizing the EEG datasets.

  10. Second-site prosthetic joint infection in patients with multiple prosthetic joints.

    Science.gov (United States)

    Clesham, Kevin; Hughes, Andrew J; O' hEireamhoin, Sven; Fleming, Catherine; Murphy, Colin G

    2018-04-10

    Prosthetic joint infections (PJIs) are among the most serious complications in arthroplasty. A second-site PJI in patients with multiple prosthetic joints increases morbidity, with many requiring further revision procedures. We aimed to establish why some patients with multiple joints develop second-site infections. Our institution's arthroplasty database was reviewed from 2004 to 2017. All PJIs were identified, and all patients with more than one prosthetic joint in situ were included. We recorded risk factors, causative organisms, number of procedures and length of stay. Forty-four patients meeting the criteria were identified. Four patients (9.1%) developed second-site infection. Eight patients (18.2%) developed re-infection of the primary PJI. Positive MRSA carrier status and PJI of a total knee replacement were associated with an increased risk of a second episode of infection. Patients who developed further infection had more frequent admission and longer lengths of stay than isolated PJIs. Higher morbidity and use of hospital resources are associated with this cohort of patients. PJIs in total knee replacements and positive MRSA status are associated with higher rates of second infection. Identifying this vulnerable cohort of patients at an early stage is critical to ensure measures are taken to reduce the risks of further infection.

  11. Sensory feedback in upper limb prosthetics.

    Science.gov (United States)

    Antfolk, Christian; D'Alonzo, Marco; Rosén, Birgitta; Lundborg, Göran; Sebelius, Fredrik; Cipriani, Christian

    2013-01-01

    One of the challenges facing prosthetic designers and engineers is to restore the missing sensory function inherit to hand amputation. Several different techniques can be employed to provide amputees with sensory feedback: sensory substitution methods where the recorded stimulus is not only transferred to the amputee, but also translated to a different modality (modality-matched feedback), which transfers the stimulus without translation and direct neural stimulation, which interacts directly with peripheral afferent nerves. This paper presents an overview of the principal works and devices employed to provide upper limb amputees with sensory feedback. The focus is on sensory substitution and modality matched feedback; the principal features, advantages and disadvantages of the different methods are presented.

  12. Prosthetic joint infection caused by Trueperella bernardiae.

    Science.gov (United States)

    Gilarranz, Raul; Chamizo, Francisco; Horcajada, Iballa; Bordes-Benítez, Ana

    2016-09-01

    Trueperella bernardiae is a Gram-positive coryneform bacilli which role as human pathogen is unknown because it has been usually considered a contaminant. Furthermore its identification by biochemical test was difficult. We describe a prosthetic joint infection in a women who years ago underwent a total knee replacement with superinfection and necrosis of the patellar tendon as major complications. In the sample of synovial fluid collected grew a gram-positive bacilli which was identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) as T. bernardiae. The patient was treated with ciprofloxacin and currently preserves the prosthesis without signs of infection. Copyright © 2016 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  13. The noncovalent bonding of antibiotics to a polytetrafluoroethylene-benzalkonium graft

    International Nuclear Information System (INIS)

    Harvey, R.A.; Greco, R.S.

    1981-01-01

    This study evaluates the noncovalent bonding of anionic antibiotics to polytetrafluoroethylene grafts using benzalkonium chloride as a cationic anchor. The binding of radiolabeled surfactants and antibiotics was evaluated by liquid scintillation and in an in vitro microbiologic assay against Staphylococcus aureus. Significant quantities of antibiotic were bound when the grafts were pretreated with benzalkonium in ethanol or aqueous solution at elevated temperature. Bound antibiotic is stable in aqueous salt solutions, but slowly dissociates in the presence of blood or serum. The ionic nature of the bonding process is clarified by the use of a variety of antibiotics and surfactants with complementary charges. The ability of the benzalkonium treated grafts to adsorb antibiotic from blood is, likewise, demonstrated and the possibility of concomitantly binding heparin and antibiotic simultaneously is evaluated. These studies support the ability to noncovalently bond antibiotics to polytetrafluoroethylene surfaces and form the basis of eventually utilizing these surfaces in the prevention of vascular prosthetic infections

  14. Rectus femoris muscle flap based on proximal insertion mobilization to cover a groin infected vascular graft.

    Science.gov (United States)

    Silvestre, Luís; Pedro, Luís Mendes; Fernandes e Fernandes, Ruy; Silva, Emanuel; Fernandes e Fernandes, José

    2015-10-01

    The rectus femoris (RF) muscle flap, which is widely used to cover groin infected vascular grafts, is usually harvested through distal tendon division and an extensive muscle elevation and transposition into the groin wound defect. A case of a vascular prosthetic graft infection in the groin was successfully controlled after coverage with an RF flap that was harvested based on proximal portion mobilization instead of the conventional distal one. This case suggests that the RF muscle flap based on proximal insertion mobilization is a feasible, effective, technically simpler, and less invasive alternative to cover infected vascular grafts in the groin. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  15. Endovascular aortic graft infection resulting in retroperitoneal abscess: report of a case

    Directory of Open Access Journals (Sweden)

    Salvatore Di Somma

    2010-06-01

    Full Text Available Infection is a rare complication of aortoiliac endovascular procedures, with an incidence inferior to 0.5%, and it may result in a retroperitoneal abscess potentially evolving to sepsis and gastrointestinal bleeding. In more than 50% of cases endovascular aortoiliac prosthetic grafts infection occur months or years after the procedure. The growing number of endovascular procedures, and as the actually midterm follow up in most cases, septic sequelae will no doubt continue to occur with increased frequency and may represent an emerging problem in the ED for the emergency physician. Endovascular graft infection begins with unspecific clinical manifestations. An high index of suspicion in any patient with an aortic stent graft presenting prolonged or recurrent fever and or abdominal or back pain and a low threshold for obtaining CT scan should increase the clinician’s ability to make a timely diagnosis in the ED setting.

  16. Prosthetic status and prosthetic need among the patients attending various dental institutes of ahmedabad and gandhinagar district, gujarat.

    Science.gov (United States)

    Shah, Vrinda R; Shah, Darshana N; Parmar, Chaitanya H

    2012-09-01

    The oral health being an integral part for the healthy living, necessity of disability limitation and rehabilitation in oral health has taken a paramount role. To assess the prosthetic status and to evaluate the prosthetic needs of the patients attending various institutes of Ahmedabad and Gandhinagar district. A total of 510 (264 males and 246 females) subjects at various dental institutes were examined in the study. A survey proforma was prepared with the help of WHO oral health assessment form (1997). Prosthetic status and prosthetic treatment need was recorded. Out of 510, any type of Edentulousness was 322 (63 %). Among them, 254 (49.8 %) were partially edentulous while 68 (13.3 %) were completely edentulous. Only 69 (13 %) were having any prosthesis in upper arch while only 80 (16 %) were having any prosthesis in lower arch. Need for any type of prosthesis in upper and lower arch was 55 and 60 % in males and females, respectively. In lower social class group need of prosthesis in upper and lower arch was 62 and 63 %, respectively. It was found that prosthetic status and prosthetic treatment need increased with increase in age. Steps should be taken to overcome this disparity and more emphasis should be given to meet the felt need of the people through government and non government organizations to improve the oral health. The unmet prosthetic treatment need should be met to rehabilitate needy people so that their disability may be limited.

  17. Studies on the properties of poly (ethylene oxide) R-150 hydrogel films formed by irradiation graft

    International Nuclear Information System (INIS)

    Yang Zhanshan; Zhu Nankang; Yang Shuqin; Qiang Yizhong

    1999-01-01

    In order to improve the mechanical properties of poly (ethylene oxide) (PEO) hydrogel film was used as wound dressing. The chemical and physical properties of the PEO R-150 graft hydrogel film formed by blends of electron beam irradiated-PEO R-150 and poly(vinyl alcohol) (PVA) were studied. The experimental results showed that the crosslinking densities of the PEO R-150 graft hydrogel increased along with the increasing of the irradiation doses and decreased with the increasing of the blend concentrations. While the PVA graft proportions did not produce obvious effects on the crosslinking density of the graft hydrogel. The crosslinking density of the graft hydrogel were obviously lower than that of the pure PVA hydrogel. The equilibrium water content of the graft hydrogel decrease as the irradiation dose and the PVA graft proportion increased; but they increased as the blend concentration increased. The equilibrium water content of the graft hydrogel was obviously higher than those of the pure PVA hydrogel. The hardness of the PVA hydrogel film increased with the irradiation dose. The hardness of the graft hydrogel decreased with the blend concentration, whereas it increased with the PVA graft proportion. The results suggest the PVA produces a main effect on the crosslinking density of the graft hydrogel, the PEO R-150 produces a main effect on the equilibrium water content of the graft hydrogel, and the both polymers have double effects on the hardness of the graft hydrogel

  18. Indium-111-labeled leukocyte scan in detection of synthetic vascular graft infection: The effect of antibiotic treatment

    International Nuclear Information System (INIS)

    Chung, C.J.; Hicklin, O.A.; Payan, J.M.; Gordon, L.

    1991-01-01

    To determine the sensitivity and specificity of the indium-111-( 111 In) labeled leukocyte scan for prosthetic vascular graft infection in patients treated with antibiotic therapy, a retrospective study was performed. Of 41 consecutive 111 In-labeled leukocyte scans performed to evaluate possible vascular graft infection, 23 scans were performed in patients treated with antibiotics. The average duration of antibiotic therapy was 21 days. Twelve positive and 11 negative scans for graft infection were found. By surgical and autopsy correlation of all positive cases, and clinical correlation (of all negative cases), there were 10 true-positive, 11 true-negative, 2 false-positive, and no false-negative scans for graft infections, for an overall sensitivity of 100% and specificity of 85%

  19. A Comparative Outcome Study of Hamstring Versus Tibialis Anterior and Synthetic Grafts for Deltoid to Triceps Transfers.

    Science.gov (United States)

    Dunn, Jennifer A; Mohammed, Khalid D; Beadel, Gordon P; Rothwell, Alastair G; Simcock, Jeremy W

    2017-10-01

    To assess elbow extension strength and complications after deltoid-triceps transfers using hamstring tendon graft compared with tibialis anterior and synthetic tendon grafts. A retrospective review of deltoid-triceps transfers in patients with tetraplegia performed between 1983 and 2014. Seventy-five people (136 arms) had surgery performed, with the majority undergoing simultaneous bilateral surgery (n = 61; 81%). Tibialis anterior tendon grafts were used in 68 arms, synthetic grafts in 23 arms, and hamstring tendon grafts in 45 arms. The average age at surgery was 31 years. Sixty-three arms (46%) were assessed between 12 and 24 months after surgery. Seventy percent of the group (n = 54) were able to extend their elbow against gravity (grade 3 of 5 or greater) following surgery. Seventy-nine percent of those with hamstring grafts achieved grade 3 of 5 or more compared with 77% with tibialis anterior and 33% with synthetic grafts. There was a statistically significant difference in postsurgery elbow extension between the tibialis anterior group and the synthetic graft group and the hamstring and the synthetic graft group but not between the tibialis anterior and the hamstring group. Complications occurred in 19 arms (14%), the majority occurring immediately after surgery and associated with the wounds. The remaining complications were with the synthetic graft group in which dehiscence of the proximal attachment occurred in 30% of the arms. Autologous tendon grafting is associated with achievement of antigravity elbow extension in a greater proportion of individuals than with prosthetic grafting. Therapeutic IV. Copyright © 2017 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  20. Arteriovenous shunt graft ulceration with sinus and graft epithelialization

    Directory of Open Access Journals (Sweden)

    Pooja Singhal

    2015-03-01

    Full Text Available Arteriovenous fistula and grafts are used as access sites for patients with chronic kidney disease and are prone for complications. Stent grafts are used to treat access site complications. We report a rare and unusual finding of epithelialization of the sinus tract and the lumen of a polytetrafluoroethylene graft, following ulceration of the overlying skin.

  1. Fixed prosthetic treatment in patients with cleft lip and palate

    Directory of Open Access Journals (Sweden)

    Bajevska Jagoda

    2017-01-01

    Full Text Available Introduction. The prosthetic treatment of patients with cleft palate includes various treatment options such as fixed partial dentures, removable partial prosthesis, etc. The type of prosthetic appliance is determined by the oral health of each individual and the circumstances. We presented three adult patients with the cleft lip and palate subjected to prosthetic treatment. Case report. From the possible prosthetic solutions according to the conditions in the oral cavity and the circumstances, fixed partial dentures veneered with composite or ceramic were chosen. A proper relationship between the teeth was reached with the fixed partial dentures, and function established, the phonetics improved and satisfying aesthetics effect accomplished improving the profile appearance of the patient’s face. Plastic surgery of the nose was performed after that. Conclusion. Multidisclipinary treatment is necessary for favourable long-term outcome in cleft lip and palate patients.

  2. The role of vision processing in prosthetic vision.

    Science.gov (United States)

    Barnes, Nick; He, Xuming; McCarthy, Chris; Horne, Lachlan; Kim, Junae; Scott, Adele; Lieby, Paulette

    2012-01-01

    Prosthetic vision provides vision which is reduced in resolution and dynamic range compared to normal human vision. This comes about both due to residual damage to the visual system from the condition that caused vision loss, and due to limitations of current technology. However, even with limitations, prosthetic vision may still be able to support functional performance which is sufficient for tasks which are key to restoring independent living and quality of life. Here vision processing can play a key role, ensuring that information which is critical to the performance of key tasks is available within the capability of the available prosthetic vision. In this paper, we frame vision processing for prosthetic vision, highlight some key areas which present problems in terms of quality of life, and present examples where vision processing can help achieve better outcomes.

  3. LEUKOCYTE AND BACTERIA IMAGING IN PROSTHETIC JOINT INFECTION

    NARCIS (Netherlands)

    Glaudemans, Andor W. J. M.; Galli, Filippo; Pacilio, Marta; Signore, Alberto

    2013-01-01

    There has been a significant increase in the number of joint prosthesis replacements worldwide. Although relatively uncommon, complications can occur with the most serious being an infection. Various radiological and nuclear imaging techniques are available to diagnose prosthetic joint infections

  4. Antithrombotic Therapy in Patients with Prosthetic Heart Valves

    Directory of Open Access Journals (Sweden)

    Mohamed HA

    2009-01-01

    Full Text Available Patients with mechanical valve prostheses require a lifelong anticoagulant treatment. The combined use of Warfarin and low-dose aspirin appears to reduce the risk of valve thrombosis and systemic embolism at a low risk of bleeding. The management of women with prosthetic heart valves during pregnancy poses a particular challenge, as there are no available controlled clinical trials to provide guidelines for effective antithrombotic therapy. Oral anticoagulants, such as Warfarin, cause foetal embryopathy; unfractionated heparin and low-molecular-weight heparin have been reported to be ineffective in preventing thromboembolic complications.This article discusses the available data and the most recent guidelines in the antithrombotic management of patients with prosthetic valves, and antithrombotic therapy in various clinical situations such as pregnant women with prosthetic heart valves, and patients with prosthetic heart valves undergoing noncardiac surgery.

  5. Mechanical performance of pyrolytic carbon in prosthetic heart valve applications.

    Science.gov (United States)

    Cao, H

    1996-06-01

    An experimental procedure has been developed for rigorous characterization of the fracture resistance and fatigue crack extension in pyrolytic carbon for prosthetic heart valve application. Experiments were conducted under sustained and cyclic loading in a simulated biological environment using Carbomedics Pyrolite carbon. While the material was shown to have modest fracture toughness, it exhibited excellent resistance to subcritical crack growth. The crack growth kinetics in pyrolytic carbon were formulated using a phenomenological description. A fatigue threshold was observed below which the crack growth rate diminishes. A damage tolerance concept based on fracture mechanics was used to develop an engineering design approach for mechanical heart valve prostheses. In particular, a new quantity, referred to as the safe-life index, was introduced to assess the design adequacy against subcritical crack growth in brittle materials. In addition, a weakest-link statistical description of the fracture strength is provided and used in the design of component proof-tests. It is shown that the structural reliability of mechanical heart valves can be assured by combining effective flaw detection and manufacturing quality control with adequate damage tolerance design.

  6. Amputation rehabilitation and prosthetic restoration. From surgery to community reintegration.

    Science.gov (United States)

    Esquenazi, Alberto

    The purpose of this review is to summarize the literature related to the advances that have taken place in the management and rehabilitation care of limb amputation. Prostheses for the lower and upper limb amputee have changed greatly over the past several years, with advances in components, socket fabrication and fitting techniques, suspension systems and sources of power and electronic controls. Higher levels of limb amputation can now be fitted with functional prostheses, which allow more patients to achieve independent life styles. This is of particular importance for the multi-limb amputee. The rehabilitation of more traditional lower limb levels of amputation have also greatly benefited from the technological advances including energy storing feet, electronic control hydraulic knees, ankle rotators and shock absorbers to mention a few. For the upper limb amputee, myoelectric and proportional controlled terminal devices and elbow joints are now used routinely in some rehabilitation facilities. Experimental prosthetic fitting techniques and devices such as the use of osseo-implantation for suspension of the prosthesis, tension control hands or electromagnetic fluids for knee movement control will also be briefly discussed in this paper. It is possible to conclude from this review that many advances have occurred that have greatly impacted the functional outcomes of patients with limb amputation.

  7. Impact Response for Two Designs of Athletic Prosthetic Feet

    Directory of Open Access Journals (Sweden)

    Mohsin N. Hamzah

    2018-03-01

    Full Text Available The present work evaluated the differences in mechanical properties of two athletic prosthetic feet samples when subjected to impact while running. Two feet samples designated as design A and B were manufactured using layers of different orientations of woven glass fiber reinforced with unsaturated polyester resin as bonding epoxy. The samples’ layers were fabricated with hand lay-up method. A theoretical study was carried out to calculate the mechanical properties of the composite material used in feet manufacturing, then experimental load-deflection test was applied at 0 degree position and 25 degree dorsiflexion feet position and impact test were applied for both feet designs to observe the behavior of the feet under static and impact loading and compare properties like stiffness, efficiency, rigidity, and shock absorption at different drop angles range from 25 degrees to 60 degrees which perform the foot positions while running. The load-deflection test result shows that the maximum deflection of the proposed design B was 32.2 mm at 0° and 38.45mm at 25°. While it was 41mm at 0˚ and 39mm at 25˚ for design A. Impact test result shows that design B foot gives peak load of 128 .7 kg with a peak time of 0.06 sec, while design Afoot gives 125.32 kg peak load with a time of 0.069 sec.

  8. Custom-made laser-welded titanium implant prosthetic abutment.

    Science.gov (United States)

    Iglesia-Puig, Miguel A

    2005-10-01

    A technique to create an individually modified implant prosthetic abutment is described. An overcasting is waxed onto a machined titanium abutment, cast in titanium, and joined to it with laser welding. With the proposed technique, a custom-made titanium implant prosthetic abutment is created with adequate volume and contour of metal to support a screw-retained, metal-ceramic implant-supported crown.

  9. ORAL HYGIENE OF PROSTHETIC DENTURE USER IN KODINGARENG ISLAND

    OpenAIRE

    NUR, NURUL KUSUMADEWI S.KG

    2008-01-01

    Objectives:to determine the level of oral hygiene for prosthetic denture user, especially for full-denture in Kodingareng Island. This researchincluded the distribution level of prosthetic denture user based on age and education.Methods: the method that used in this research is observational descriptive withcross sectional-studyas the research design. Variable result of the research determined in to 3, those are bad, middle, and good. Result:the highest percentage o...

  10. Graft Copolymerization Of Methyl Methacrylate Onto Agave Cellulose

    International Nuclear Information System (INIS)

    Noor Afizah Rosli; Ishak Ahmad; Ibrahim Abdullah; Farah Hannan Anuar

    2014-01-01

    The grafting polymerization of methyl methacrylate (MMA) and Agave cellulose was prepared and the grafting reaction conditions were optimized by varying the reaction time and temperature, and ratio of monomer to cellulose. The resulting graft copolymers were characterized by Fourier transform infrared, X-ray diffraction analysis, thermogravimetric analysis, and scanning electron microscopy (SEM). The experimental results showed that the optimal conditions were at a temperature of 45 degree Celsius for 90 min with ratio monomer to cellulose at 1:1 (g/ g). An additional peak at 1738 cm -1 which was attributed to the C=O of ester stretching vibration of poly(methyl methacrylate), appeared in the spectrum of grafted Agave cellulose. A slight decrease of crystallinity index upon grafting was found from 0.74 to 0.68 for cellulose and grafted cellulose, respectively. Grafting of MMA onto cellulose enhanced its thermal stability and SEM observation further furnished evidence of grafting MMA onto Agave cellulose with increasing cellulose diameter and surface roughness. (author)

  11. Maxillary sinus augmentation using sinus membrane elevation without grafts - A Systematic Review

    Directory of Open Access Journals (Sweden)

    Rakshith Hegde

    2016-01-01

    Full Text Available Implants have a predictable outcome and are the foremost treatment modality for prosthetic rehabilitation of edentulous patients. Due to loss of bone after extraction and pneumatization of maxillary sinus, there is insufficient bone volume for implant placement. The direct maxillary sinus lift procedure has been performed with different grafting materials (autogenous bone grafts, alloplasts, allografts, and xenografts and without grafting material, having new bone formation around the implant. There is no evidence to prove the need for grafting material in all direct sinus lift procedures, hence the need for this review. Previous meta-analysis showed that survival rates of implants placed in grafted maxillary sinuses had similar survival rates whether autogenous, allogenous, or alloplastic grafts were used. This paper aims to review scientific data on the direct sinus elevation technique without use of any grafting material, volume of new bone formed, and also mechanism behind this technique. Articles were searched from 1997 to October 2014 in PubMed, Google Scholar, and Cochrane CENTRAL. The study eligibility criteria were (1 direct sinus lift procedure without any graft material during implant placement and (2 human or animal studies with a minimum follow-up of 6 months or more. Two authors independently scrutinized the literature and if any controversy was raised, third author's opinion was sought to arrive at a mutual consensus for including the study in the review. Due to the heterogeneity across all studies in all study designs, the data were not pooled and a meta-analysis was not performed. Taking into consideration all factors reviewed in this regard along with the outcomes, the direct sinus lift technique without grafting can be suggested as a viable treatment option keeping in mind the limitations involved. The average bone gain was seen across all studies ranging from 2.37 to 10 mm and with an implant survival rate ranging from 79

  12. Graft type for femoro-popliteal bypass surgery.

    Science.gov (United States)

    Ambler, Graeme K; Twine, Christopher P

    2018-02-11

    Femoro-popliteal bypass is implemented to save limbs that might otherwise require amputation, in patients with ischaemic rest pain or tissue loss; and to improve walking distance in patients with severe life-limiting claudication. Contemporary practice involves grafts using autologous vein, polytetrafluoroethylene (PTFE) or Dacron as a bypass conduit. This is the second update of a Cochrane review first published in 1999 and last updated in 2010. To assess the effects of bypass graft type in the treatment of stenosis or occlusion of the femoro-popliteal arterial segment, for above- and below-knee femoro-popliteal bypass grafts. For this update, the Cochrane Vascular Information Specialist searched the Vascular Specialised Register (13 March 2017) and CENTRAL (2017, Issue 2). Trial registries were also searched. We included randomised trials comparing at least two different types of femoro-popliteal grafts for arterial reconstruction in patients with femoro-popliteal ischaemia. Randomised controlled trials comparing bypass grafting to angioplasty or to other interventions were not included. Both review authors (GKA and CPT) independently screened studies, extracted data, assessed trials for risk of bias and graded the quality of the evidence using GRADE criteria. We included nineteen randomised controlled trials, with a total of 3123 patients (2547 above-knee, 576 below-knee bypass surgery). In total, nine graft types were compared (autologous vein, polytetrafluoroethylene (PTFE) with and without vein cuff, human umbilical vein (HUV), polyurethane (PUR), Dacron and heparin bonded Dacron (HBD); FUSION BIOLINE and Dacron with external support). Studies differed in which graft types they compared and follow-up ranged from six months to 10 years.Above-knee bypassFor above-knee bypass, there was moderate-quality evidence that autologous vein grafts improve primary patency compared to prosthetic grafts by 60 months (Peto odds ratio (OR) 0.47, 95% confidence interval (CI

  13. Rotationplasty with vascular reconstruction for prosthetic knee joint infection.

    Science.gov (United States)

    Fujiki, Masahide; Miyamoto, Shimpei; Nakatani, Fumihiko; Kawai, Akira; Sakuraba, Minoru

    2015-01-01

    Rotationplasty is used most often as a function-preserving salvage procedure after resection of sarcomas of the lower extremity; however, it is also used after infection of prosthetic knee joints. Conventional vascular management during rotationplasty is to preserve and coil major vessels, but recently, transection and reanastomosis of the major vessels has been widely performed. However, there has been little discussion regarding the optimal vascular management of rotationplasty after infection of prosthetic knee joints because rotationplasty is rarely performed for this indication. We reviewed four patients who had undergone resection of osteosarcomas of the femur, placement of a prosthetic knee joint, and rotationplasty with vascular reconstruction from 2010 to 2013. The mean interval between prosthetic joint replacement and rotationplasty was 10.4 years and the mean interval between the diagnosis of prosthesis infection and rotationplasty was 7.9 years. Rotationplasty was successful in all patients; however, in one patient, arterial thrombosis developed and necessitated urgent surgical removal and arterial reconstruction. All patients were able to walk independently with a prosthetic limb after rehabilitation. Although there is no consensus regarding the most appropriate method of vascular management during rotationplasty for revision of infected prosthetic joints, vascular transection and reanastomosis is a useful option.

  14. Haemodynamics in axillobifemoral bypass grafts

    NARCIS (Netherlands)

    C.H. Wittens

    1992-01-01

    textabstractThis thesis is based on four publications on the subject of graft configuration and haemodynamics in axillobifemoral bypass grafts: 1. A clinical evaluation of 17 patients with axillobifemoral bypass graft operations, performed for various indications. Two important observations were

  15. A comparative study of the regenerative effect of sinus bone grafting with platelet-rich fibrin-mixed Bio-Oss® and commercial fibrin-mixed Bio-Oss®: an experimental study.

    Science.gov (United States)

    Xuan, Feng; Lee, Chun-Ui; Son, Jeong-Seog; Jeong, Seung-Mi; Choi, Byung-Ho

    2014-06-01

    Anorganic bovine bone (Bio-Oss®) particles are one of the most popular grafting materials. The particles are often mixed with platelet-rich fibrin (PRF) or a commercial fibrin (Tisseel®) to form a mouldable graft material. The objective of this study was to compare the potentials of PRF-mixed Bio-Oss® and Tisseel®-mixed Bio-Oss® to enhance bone regeneration in a canine sinus model. Six mongrel dogs were used in this study. After elevating the sinus membrane in both maxillary sinus cavities, an implant was placed into the sinus cavity. In one of the sinus cavities, the PRF/Bio-Oss® composite was grafted, and the Tisseel®/Bio-Oss® composite was grafted in the other sinus cavity. After a 6 month healing period, bone formation in the graft sites and bone-implant contact were evaluated. The mean osseointegration rate was 43.5 ± 12.4% and new bone formation rate 41.8 ± 5.9% in the PRF/Bio-Oss® composite sites. In the Tisseel®/Bio-Oss® composite sites they were 30.7 ± 7.9% and 31.3 ± 6.4%. There were statistically significant differences between the groups. The findings from this study suggest that when platelet-rich fibrin is used as an adjunct to Bio-Oss® particles for bone augmentation in the maxillary sinus, bone formation in the graft sites is significantly greater than when Tisseel® is used. Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  16. Prosthetic Status and Prosthetic Need Among the Patients Attending Various Dental Institutes of Ahmedabad and Gandhinagar District, Gujarat

    OpenAIRE

    Shah, Vrinda R.; Shah, Darshana N.; Parmar, Chaitanya H.

    2012-01-01

    The oral health being an integral part for the healthy living, necessity of disability limitation and rehabilitation in oral health has taken a paramount role. To assess the prosthetic status and to evaluate the prosthetic needs of the patients attending various institutes of Ahmedabad and Gandhinagar district. A total of 510 (264 males and 246 females) subjects at various dental institutes were examined in the study. A survey proforma was prepared with the help of WHO oral health assessment ...

  17. Primary renal graft thrombosis

    NARCIS (Netherlands)

    Bakir, N; Sluiter, WJ; Ploeg, RJ; van Son, WJ; Tegzess, Adam

    Background. Renal allograft thrombosis is a serious complication of kidney transplantation that ultimately leads to graft loss. Its association with acute and hyperacute rejection is well documented; however, in a large proportion of patients the precise cause remains obscure. The exact incidence

  18. Aortic Graft Infection Secondary to Iatrogenic Transcolonic Graft Malposition.

    Science.gov (United States)

    Blank, Jacqueline J; Rothstein, Abby E; Lee, Cheong Jun; Malinowski, Michael J; Lewis, Brian D; Ridolfi, Timothy J; Otterson, Mary F

    2018-01-01

    Aortic graft infections are a rare but devastating complication of aortic revascularization. Often infections occur due to contamination at the time of surgery. Iatrogenic misplacement of the limbs of an aortobifemoral graft is exceedingly rare, and principles of evaluation and treatment are not well defined. We report 2 cases of aortobifemoral bypass graft malposition through the colon. Case 1 is a 54-year-old male who underwent aortobifemoral bypass grafting for acute limb ischemia. He had previously undergone a partial sigmoid colectomy for diverticulitis. Approximately 6 months after vascular surgery, he presented with an occult graft infection. Preoperative imaging and intraoperative findings were consistent with graft placement through the sigmoid colon. Case 2 is a 60-year-old male who underwent aortobifemoral bypass grafting due to a nonhealing wound after toe amputation. His postoperative course was complicated by pneumonia, bacteremia thought to be secondary to the pneumonia, general malaise, and persistent fevers. Approximately 10 weeks after the vascular surgery, he presented with imaging and intraoperative findings of graft malposition through the cecum. Aortic graft infection is usually caused by surgical contamination and presents as an indolent infection. Case 1 presented as such; Case 2 presented more acutely. Both grafts were iatrogenically misplaced through the colon at the index operation. The patients underwent extra-anatomic bypass and graft explantation and subsequently recovered.

  19. Influences of irradiation on the anastomotic sites of artificial graft

    International Nuclear Information System (INIS)

    Ogawa, Junichi; Inoue, Hiroshi; Koide, Shirosaku; Kawada, Shimei; Shotsu, Akira

    1989-01-01

    To examine the acute influences of irradiation on the anastomotic sites of EPTFE vascular grafts, experimental study was performed using canine dogs. After replacement of superior vena cava and bilateral femoral arteries with EPTFE grafts, a total of 20 to 100 Gy doses were given at the anastomotic sites of superior vena cava and right femoral artery. There were no degradation of grafts themselves or rupture in the anastomoses at cumulative anastomotic sites of superior vena cava, stenoses and/or overgrowth of granulation tissues were observed, although at those of right femoral artery, no remarkable differences were observed between dogs which received irradiation and those which did not receive. (author)

  20. Consumer design priorities for upper limb prosthetics.

    Science.gov (United States)

    Biddiss, Elaine; Beaton, Dorcas; Chau, Tom

    2007-11-01

    To measure consumer satisfaction with upper limb prosthetics and provide an enumerated list of design priorities for future developments. A self-administered, anonymous survey collected information on participant demographics, history of and goals for prosthesis use, satisfaction, and design priorities. The questionnaire was available online and in paper format and was distributed through healthcare providers, community support groups, and one prosthesis manufacturer; 242 participants of all ages and levels of upper limb absence completed the survey. Rates of rejection for myoelectric hands, passive hands, and body-powered hooks were 39%, 53%, and 50%, respectively. Prosthesis wearers were generally satisfied with their devices while prosthesis rejecters were dissatisfied. Reduced prosthesis weight emerged as the highest priority design concern of consumers. Lower cost ranked within the top five design priorities for adult wearers of all device types. Life-like appearance is a priority for passive/cosmetic prostheses, while improved harness comfort, wrist movement, grip control and strength are required for body-powered devices. Glove durability, lack of sensory feedback, and poor dexterity were also identified as design priorities for electric devices. Design priorities reflect consumer goals for prosthesis use and vary depending on the type of prosthesis used and age. Future design efforts should focus on the development of more light-weight, comfortable prostheses.

  1. Analytical Study of Active Prosthetic Legs

    Science.gov (United States)

    Ono, Kyosuke; Katsumata, Mie

    Walking with prosthesis has not been well analyzed mathematically and it seems that the design of powered prosthesis has been done empirically so far. This paper presents a dynamic simulation of a normal human walking and walking with an active prosthesis. We also studied the two controlling methods of a powered thigh prosthesis based on multi-body simulation of human walking. First we measured the normal human walking gait, then, we showed that a 3-DOF human walking model can walk on level ground by applying tracking control to the measured walking gait within a certain range of tuned walking period. Next, we applied the tracking control and self-excited control to the powered thigh prosthesis and compared the robustness and efficiency of the two control methods by numerical simulation. As a result, we found that the self-excited control can significantly decrease the hip joint torque and specific cost to 1/3 compared with the tracking control. Moreover, the self-excited control is superior to the tracking control because tuning for the walking period is not needed for the active prosthetic leg.

  2. Surface EMG in advanced hand prosthetics.

    Science.gov (United States)

    Castellini, Claudio; van der Smagt, Patrick

    2009-01-01

    One of the major problems when dealing with highly dexterous, active hand prostheses is their control by the patient wearing them. With the advances in mechatronics, building prosthetic hands with multiple active degrees of freedom is realisable, but actively controlling the position and especially the exerted force of each finger cannot yet be done naturally. This paper deals with advanced robotic hand control via surface electromyography. Building upon recent results, we show that machine learning, together with a simple downsampling algorithm, can be effectively used to control on-line, in real time, finger position as well as finger force of a highly dexterous robotic hand. The system determines the type of grasp a human subject is willing to use, and the required amount of force involved, with a high degree of accuracy. This represents a remarkable improvement with respect to the state-of-the-art of feed-forward control of dexterous mechanical hands, and opens up a scenario in which amputees will be able to control hand prostheses in a much finer way than it has so far been possible.

  3. A rare case of acyanotic congenital heart disease, large patent ductus arteriosus with pre-ductal coarctation of descending thoracic aorta with patent ductus arteriosus closure and extra anatomical bypass grafting

    Directory of Open Access Journals (Sweden)

    Zara Wani

    2017-01-01

    Full Text Available We report a case of 18-year-old female patient with large patent ductus arteriosus (PDA-preductal coarctation of descending thoracic aorta. She underwent large PDA closure with a prosthetic graft from ascending aorta to descending thoracic aorta by mid-sternotomy on cardiopulmonary bypass machine under total hypothermic circulatory arrest.

  4. A rare case of acyanotic congenital heart disease, large patent ductus arteriosus with pre-ductal coarctation of descending thoracic aorta with patent ductus arteriosus closure and extra anatomical bypass grafting.

    Science.gov (United States)

    Wani, Zara; Tiwari, Deepak; Gehlot, Rajeev; Kumar, Deepak; Chhabra, Sushil; Sharma, Meenaxi

    2017-01-01

    We report a case of 18-year-old female patient with large patent ductus arteriosus (PDA)-preductal coarctation of descending thoracic aorta. She underwent large PDA closure with a prosthetic graft from ascending aorta to descending thoracic aorta by mid-sternotomy on cardiopulmonary bypass machine under total hypothermic circulatory arrest.

  5. “In vitro” Implantation Technique Based on 3D Printed Prosthetic Prototypes

    Science.gov (United States)

    Tarnita, D.; Boborelu, C.; Geonea, I.; Malciu, R.; Grigorie, L.; Tarnita, D. N.

    2018-06-01

    In this paper, Rapid Prototyping ZCorp 310 system, based on high-performance composite powder and on resin-high strength infiltration system and three-dimensional printing as a manufacturing method are used to obtain physical prototypes of orthopaedic implants and prototypes of complex functional prosthetic systems directly from the 3D CAD data. These prototypes are useful for in vitro experimental tests and measurements to optimize and obtain final physical prototypes. Using a new elbow prosthesis model prototype obtained by 3D printing, the surgical technique of implantation is established. Surgical implantation was performed on male corpse elbow joint.

  6. Characterization of materials for prosthetic implants using the BEAMnrc Monte Carlo code

    International Nuclear Information System (INIS)

    Spezi, E; Palleri, F; Angelini, A L; Ferri, A; Baruffaldi, F

    2007-01-01

    Metallic implants degrade image quality and perturb severely the patient dose distribution in external beam radiotherapy. Furthermore, conventional treatment planning systems (TPS) do not accurately account for tissue heterogeneities, especially at the interfaces where high Z gradients are present. This work deals with the accurate and systematic characterization of materials used for prosthetic implants. The dose calculation engine used in this investigation is the BEAMnrc Monte Carlo code. A detailed comparison versus experimental data was carried out for two clinical photon beam energies (6MV and 18MV). Our results show that in both cases a very good agreement (within ± 2%) between calculations and experiments was achieved

  7. Improvement of grafting procedures for the ornamental species: II. Abies concolor [(Gord. & Glend. Lindl

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2012-06-01

    Full Text Available The achieved results concerning the grafting silver-fir - Abies concolor [(Gord. & Glend. Lindl] scions on white-fir (Abies alba Mill. rootstocks are reporting in this article. The double-side-veneer grafting method and the plastic tape and the ecological CeraltinŽ wax were applied in four experimental variants. The side-veneer-grafting method and the classic materials, such as raffia and the hot wax were used at the two controls involved in this experiment. The grafting success expressed in percents, were transformed in arcsin square root of percent values, and a two-way analysis of variance was performed. Highly significant (p < 0.001 statistical differences were found between grafting variants, including controls. The Duncan Multiple Range Test showed that the four experimental grafting variants were highly significantly (p < 0.01 be-tter than the two controls. The grafting success of the best experimental variant has surpassed the two controls by 129 and 153%, respectively. Consequently, the double-side-veneer grafting method, the new developed plastic tape and the ecological CeraltinŽ wax have contributed to this grafting success owing to which they are recommended to be used for grafting silver-fir ornamental trees.

  8. Hydrogen, a potential safeguard for graft-versus-host disease and graft ischemia-reperfusion injury?

    Science.gov (United States)

    Yuan, Lijuan; Shen, Jianliang

    2016-01-01

    Post-transplant complications such as graft-versus-host disease and graft ischemia-reperfusion injury are crucial challenges in transplantation. Hydrogen can act as a potential antioxidant, playing a preventive role against post-transplant complications in animal models of multiple organ transplantation. Herein, the authors review the current literature regarding the effects of hydrogen on graft ischemia-reperfusion injury and graft-versus-host disease. Existing data on the effects of hydrogen on ischemia-reperfusion injury related to organ transplantation are specifically reviewed and coupled with further suggestions for future work. The reviewed studies showed that hydrogen (inhaled or dissolved in saline) improved the outcomes of organ transplantation by decreasing oxidative stress and inflammation at both the transplanted organ and the systemic levels. In conclusion, a substantial body of experimental evidence suggests that hydrogen can significantly alleviate transplantation-related ischemia-reperfusion injury and have a therapeutic effect on graft-versus-host disease, mainly via inhibition of inflammatory cytokine secretion and reduction of oxidative stress through several underlying mechanisms. Further animal experiments and preliminary human clinical trials will lay the foundation for hydrogen use as a drug in the clinic. PMID:27652837

  9. Prosthetic ankle push-off work reduces metabolic rate but not collision work in non-amputee walking

    OpenAIRE

    Caputo, Joshua M.; Collins, Steven H.

    2014-01-01

    Individuals with unilateral below-knee amputation expend more energy than non-amputees during walking and exhibit reduced push-off work and increased hip work in the affected limb. Simple dynamic models of walking suggest a possible solution, predicting that increasing prosthetic ankle push-off should decrease leading limb collision, thereby reducing overall energy requirements. We conducted a rigorous experimental test of this idea wherein ankle-foot prosthesis push-off work was incrementall...

  10. The γ-radiation induced grafting of unsaturated segmented polyurethanes with N-vinyl pyrrolidone

    International Nuclear Information System (INIS)

    Egboh, S.H.; George, M.H.; Barrie, J.A.

    1984-01-01

    Linear unsaturated segmented polyurethanes have been modified by hydrophilic grafting at 40 deg C with N-vinyl pyrrolidone, in N,N-dimethylformamide as solvent, using 60 Cobalt γ-irradiation. Graft copolymers were isolated from homopolymers by selective solvent extraction using a Soxhlet apparatus. The effects of reaction time, total dose, temperature and monomer concentration, on the graft yields have been examined. Relatively high irradiation doses were avoided during the grafting experiments to prevent possible degradation of the segmented polyurethanes and gelation of the homopolymer, poly(N-vinyl pyrrolidone). The ungrafted and grafted copolymers were characterized, and the graft copolymers were shown to be more thermally stable than the original polyurethanes, by thermogravimetric analysis. An explanation for the observed variation of the graft yields with some of the experimental variables is suggested. (author)

  11. In vivo quantitation of platelet deposition on human peripheral arterial bypass grafts using indium-111-labeled platelets. Effect of dipyridamole and aspirin

    International Nuclear Information System (INIS)

    Pumphrey, C.W.; Chesebro, J.H.; Dewanjee, M.K.; Wahner, H.W.; Hollier, L.H.; Pairolero, P.C.; Fuster, V.

    1983-01-01

    Indium-111-labeled autologous platelets, injected 48 hours after operation, were used to evaluate the thrombogenicity of prosthetic material and the effect of platelet inhibitor therapy in vivo. Dacron double-velour (Microvel) aortofemoral artery bifurcation grafts were placed in 16 patients and unilateral polytetrafluoroethylene femoropopliteal grafts were placed in 10 patients. Half the patients in each group received platelet inhibitors before operation (dipyridamole, 100 mg 4 times a day) and after operation (dipyridamole, 75 mg, and acetylsalicylic acid, 325 mg 3 times a day); the rest of the patients served as control subjects. Five-minute scintigrams of the graft region were taken with a gamma camera interfaced with a computer 48, 72, and 96 hours after injection of the labeled platelets. Platelet deposition was estimated from the radioactivities of the grafts and expressed as counts per 100 pixels per microcurie injected. Dipyridamole and aspirin therapy significantly reduced the number of platelets deposited on Dacron grafts and prevented platelet accumulation over 3 days. With the small amount of platelet deposition on polytetrafluoroethylene femoropopliteal artery grafts even in control patients, platelet inhibitor therapy had no demonstrable effect on platelet deposition on these grafts. It is concluded that (1) platelet deposition on vascular grafts in vivo can be quantitated by noninvasive methods, and (2) dipyridamole and aspirin therapy reduced platelet deposition on Dacron aortofemoral artery grafts

  12. Pannus-related prosthetic valve dysfunction. Case report.

    Science.gov (United States)

    Moldovan, Maria-Sînziana; Bedeleanu, Daniela; Kovacs, Emese; Ciumărnean, Lorena; Molnar, Adrian

    2016-01-01

    Pannus-related prosthetic valve dysfunction, a complication of mechanical prosthetic valve replacement, is rare, with a slowly progressive evolution, but it can be acute, severe, requiring surgical reintervention. We present the case of a patient with a mechanical single disc aortic prosthesis, with moderate prosthesis-patient mismatch, minor pannus found on previous ultrasound examinations, who presented to our service with angina pain with a duration of 1 hour, subsequently interpreted as non-ST segment elevation myocardial infarction (NSTEMI) syndrome. Coronarography showed normal epicardial coronary arteries, an ample movement of the prosthetic disc, without evidence of coronary thromboembolism, and Gated Single-Photon Emission Computerized Tomography (SPECT) with Technetium (Tc)-99m detected no perfusion defects. Transthoracic echocardiography (TTE) evidenced a dysfunctional prosthesis due to a subvalvular mass; transesophageal echocardiography (TOE) showed the interference of this mass, with a pannus appearance, with the closure of the prosthetic disc. Under conditions of repeated angina episodes, under anticoagulant treatment, surgery was performed, with the intraoperative confirmation of pannus and its removal. Postoperative evolution was favorable. This case reflects the diagnostic and therapeutic management problems of pannus-related prosthetic valve dysfunction.

  13. Prosthetic implant treatment of the edentulous maxilla with overdenture.

    Science.gov (United States)

    Inversini, M

    2006-10-01

    The literature concerning the success of prosthetic implant treatment with maxillary overdenture is reviewed, and variables affecting treatment from the implant and prosthetic standpoint are analysed. Guidelines for the fabrication of maxillary overimplants comparable to those for mandibular overimplants are still lacking, as are evidence-based prosthetic design concepts. Individual methods and techniques have been described, but evaluation standards for the outcome of maxillary prosthetic-implant treatment are lacking or individually interpreted. The biomechanics involved in the proposed system are described, together with the advantages of telescopic crowns for the retention of removable partial prosthesis supported by maxillary implants. The positive influence, in terms of long-term prognosis, of the perio-protective design of removable partial prostheses supported by maxillary overimplants is also discussed. The proposed system not only provides stability, support and retention for removable partial prostheses supported by maxillary implants, but also enables implant survival rates to be improved, both for biomechanical reasons and due to improved oral hygiene. The simplification of fabrication procedures, repair, rebasing and re-operating also reduce the cost of follow-up and improve the cost/benefit ratio. However, additional studies are needed to clarify the number and most appropriate distribution of implants, as well as the most favourable prosthetic designs for maxillary overimplants.

  14. Provision of Prosthetic Services Following Lower Limb Amputation in Malaysia

    Science.gov (United States)

    Arifin, Nooranida; Hasbollah, Hasif Rafidee; Hanafi, Muhammad Hafiz; Ibrahim, Al Hafiz; Rahman, Wan Afezah Wan Abdul; Aziz, Roslizawati Che

    2017-01-01

    The incidence of lower limb amputation is high across the globe and continues to be a major threat to morbidity and mortality. Consequently, the provision of high quality and effective prosthetics services have been known as an essential component for a successful rehabilitation outcome. In Malaysia, amputation prevalence has been increasing in which several main components of service delivering aspects (such as service intervention, prosthetic personnel) should be anticipated to accommodate for the increasing demand. This article highlights the hurdles experienced in providing prosthetic services in Malaysia from multiple aspects such as financial burden to acquire the prosthesis and lack of expertise to produce quality prosthesis. This paramount issues consequently justify for the urgency to carry out national level survey on the current statistics of lower limb amputation and to ascertain the available workforce to provide a quality prosthetics services. Only with accurate and current information from the national survey, strategies and policies aimed at enhancing the outcome from prosthetics services can be achieved. PMID:29386978

  15. Vein grafting in fingertip replantations.

    Science.gov (United States)

    Yan, Hede; Jackson, William D; Songcharoen, Somjade; Akdemir, Ovunc; Li, Zhijie; Chen, Xinglong; Jiang, Liangfu; Gao, Weiyang

    2009-01-01

    In this retrospective study, the survival rates of fingertip replantation with and without vein grafting were evaluated along with their postoperative functional and cosmetic results. One hundred twenty-one-fingertip amputations were performed in 103 patients between September 2002 and July 2007. Thirty-four amputated fingertips were replanted without vein grafting, while 87 amputated fingertips were replanted with vein grafting for arterial and/or venous repairs. The overall survival rates of the replantations with and without vein grafting were 90% (78/87) and 85% (29/34), respectively. The survival rates were 88% (36/41) with venous repair, 93% (25/27) with arterial repair, and 89% (17/19) with both. Nineteen patients without vein grafting and 48 patients with vein grafting had a follow-up period of more than one year. Good cosmetic and functional outcomes were observed in both groups of patients. The results show that vein grafting is a reliable technique in fingertip replantations, showing no significant difference (P > 0.05) in survival between those with and without vein grafting. Furthermore, no significant difference (P > 0.05) in survival was found between cases with vein grafts for arterial and/or venous repairs. In fingertip replantations with vein grafting, favorable functional and esthetic results can be achieved without sacrificing replantation survival. (c) 2009 Wiley-Liss, Inc.

  16. Prosthetic bypass for restenosis after endarterectomy or stenting of the carotid artery.

    Science.gov (United States)

    Illuminati, Giulio; Belmonte, Romain; Schneider, Fabrice; Pizzardi, Giulia; Calió, Francesco G; Ricco, Jean-Baptiste

    2017-06-01

    The objective of this study was to evaluate the results of prosthetic carotid bypass (PCB) with polytetrafluoroethylene (PTFE) grafts as an alternative to carotid endarterectomy (CEA) in treatment of restenosis after CEA or carotid artery stenting (CAS). From January 2000 to December 2014, 66 patients (57 men and 9 women; mean age, 71 years) presenting with recurrent carotid artery stenosis ≥70% (North American Symptomatic Carotid Endarterectomy Trial [NASCET] criteria) were enrolled in a prospective study in three centers. The study was approved by an Institutional Review Board. Informed consent was obtained from all patients. During the same period, a total of 4321 CEAs were completed in the three centers. In these 66 patients, the primary treatment of the initial carotid artery stenosis was CEA in 57 patients (86%) and CAS in nine patients (14%). The median delay between primary and redo revascularization was 32 months. Carotid restenosis was symptomatic in 38 patients (58%) with transient ischemic attack (n = 20) or stroke (n = 18). In this series, all patients received statins; 28 patients (42%) received dual antiplatelet therapy, and 38 patients (58%) received single antiplatelet therapy. All PCBs were performed under general anesthesia. No shunt was used in this series. Nasal intubation to improve distal control of the internal carotid artery was performed in 33 patients (50%), including those with intrastent restenosis. A PTFE graft of 6 or 7 mm in diameter was used in 6 and 60 patients, respectively. Distal anastomosis was end to end in 22 patients and end to side with a clip distal to the atherosclerotic lesions in 44 patients. Completion angiography was performed in all cases. The patients were discharged under statin and antiplatelet treatment. After discharge, all of the patients underwent clinical and Doppler ultrasound follow-up every 6 months. Median length of follow-up was 5 years. No patient died, sustained a stroke, or presented with a

  17. [Value of preserved saphenous vein graft for the creation of access ports in hemodialyzed patients: report of 309 cases].

    Science.gov (United States)

    Schneider, Marc; Barrou, Benoît; Cluzel, Philippe; Hamani, Aziz; Bitker, Marc-Olivier; Richard, François

    2003-09-01

    Biological grafts are rarely used for the creation of vascular access, despite their many advantages. Our group prefers to use distal vascular accesses with interposition of a biological graft when direct access cannot be achieved. The objective of this study was to determine the long-term patency and the complication rate of a series of 309 vascular access procedures using a preserved saphenous (PS) vein homograft. 410 (27%) of the 1,500 vascular access procedures performed by our group required the use of a graft, including 376 PS vein homografts (25%). This retrospective study comprised complete data collection for 309 arteriovenous fistulas (AVF) using preserved saphenous (PS) vein graft in the forearm performed in 267 patients between 1985 and 2000. Primary patency was defined as the interval between creation of the vascular access and the first complication requiring surgical or radiological correction; secondary patency was defined as the interval between creation and loss of the graft, with or without revision of the fistula. Survival rates were calculated according to the Kaplan-Meier method. Inter-group comparison was performed by the Logrank test and analysis of variance was performed by logistic regression. Primary patency rates were 77%, 40% and 27% at 1,2 and 5 years, respectively. Secondary patency rates were 79% and 47% at 1 year and 5 years, respectively. The thrombosis rate was 42%. Two episodes of thrombosis occurred in 25% of grafts and 3 episodes were observed in 10% of cases. Infection rates were 1.9% postoperatively and 5% after dialysis, respectively. An aneurysm occurred on 10% of grafts. The operator's experience (RR = 1.58; p creation of vascular accesses with similar patency rates to those of prosthetic grafts. Vein grafts present a number of advantages, particularly a greater ease of use facilitating distal implantation of the graft and a low infection rate.

  18. Image segmentation for enhancing symbol recognition in prosthetic vision.

    Science.gov (United States)

    Horne, Lachlan; Barnes, Nick; McCarthy, Chris; He, Xuming

    2012-01-01

    Current and near-term implantable prosthetic vision systems offer the potential to restore some visual function, but suffer from poor resolution and dynamic range of induced phosphenes. This can make it difficult for users of prosthetic vision systems to identify symbolic information (such as signs) except in controlled conditions. Using image segmentation techniques from computer vision, we show it is possible to improve the clarity of such symbolic information for users of prosthetic vision implants in uncontrolled conditions. We use image segmentation to automatically divide a natural image into regions, and using a fixation point controlled by the user, select a region to phosphenize. This technique improves the apparent contrast and clarity of symbolic information over traditional phosphenization approaches.

  19. Obtention of a prosthetic group for labelling of radioiodinated proteins

    International Nuclear Information System (INIS)

    Santos, Josefina da S.; Colturato, Maria Tereza; Araujo, Elaine B. de

    2000-01-01

    Antibodies and peptides labeled with radionuclides has been extensively used in radioimmunotherapy and radioimmunodetection. The principal problem with the use of radioiodinated proteins is the in vivo dehalogenation. The use of prosthetic groups for indirect labeling of proteins with radioiodine has showed to be useful on labeling proteins with greater in vivo stability. A procedure is described for the preparation of an radioiodinated prosthetic group (N-succinimidyl 4-radioiodine-benzoate-SIB), using procedure described by Stocklin et al, with the iodination of p-bromo-benzoic acid and subsequent reaction with TSTU. Preliminary labeling results showed that the prosthetic group can be obtained in a good yield. The coupling of the SIB to the protein will be studied using human IgG as protein model. (author)

  20. Surgical-prosthetic treatment of large mandibular cysts

    Directory of Open Access Journals (Sweden)

    Džambas Ljubiša D.

    2003-01-01

    Full Text Available This paper presents a combined surgical-prosthetic procedure of reconstructing mandibular bone defect in a 53 year old patient, following enucleation of a mandibular cyst (Cystectomy Partsch II. After a thorough diagnostic evaluation, a surgical procedure was planned with the particular attention to the nature of the disease, patient’s condition, size and extension of the cyst, tissue loss, and the possibilities of prosthetic management of a mandibular bone defect with partial postresection dental prosthesis. It is of great importance to point to the significance of teamwork of a maxillofacial surgeon and a specialist in prosthodontics. This kind of cooperation provided very effective and less risky soft tissue, as well as bone tissue regeneration (osteogenesis. The patient’s recovery was fast, and he could return to his daily activities and work without significant changes regarding quality of life after surgery and prosthetic treatment.

  1. Granulicatella adiacens prosthetic hip joint infection after dental treatment.

    Science.gov (United States)

    Aweid, Osama; Sundararajan, Sabapathy; Teferi, Abraham

    2016-06-01

    Granulicatella adiacens is a Gram-positive bacteria and a normal component of oral flora. It is also found in dental plaques, endodontic abscesses and can rarely cause more serious infections. We describe a prosthetic hip joint infection in an 81-year-old fit and healthy man due to Granulicatella adiacens who underwent a prolonged dental intervention two days earlier without antibiotic prophylaxis. The infection was successfully treated with surgical intervention and a combination of antibiotics. The patient eventually succumbed to severe community-acquired pneumonia two months later. Current guidelines recommend avoidance of antibiotic prophylaxis prior to dental treatment in patients who have no co-morbidities and no prior operation on the index prosthetic joint. This case report indicates that infections of prosthetic joints may be associated with dental procedures even in fit and healthy patients without the recognized risk factors.

  2. Future Research Opportunities in Peri-Prosthetic Joint Infection Prevention.

    Science.gov (United States)

    Berbari, Elie; Segreti, John; Parvizi, Javad; Berríos-Torres, Sandra I

    Peri-prosthetic joint infection (PJI) is a serious complication of prosthetic joint arthroplasty. A better understanding and reversal of modifiable risk factors may lead to a reduction in the incidence of incisional (superficial and deep) and organ/space (e.g., PJI) surgical site infections (SSI). Recently, the Centers for Disease Control and Prevention (CDC) and the Healthcare Infection Control Practices Advisory Committee (HICPAC) published the Guideline for Prevention of Surgical Site Infection. This targeted update applies evidence-based methodology in drafting recommendations for potential strategies to reduce the risk of SSI both across surgical procedures and specifically in prosthetic joint arthroplasty. A panel of PJI content experts identified nine PJI prevention research opportunities based on both evidence gaps identified through the guideline development process (transfusion, immunosuppressive therapy, anticoagulation, orthopedic space suit, and biofilm) and expert opinion (anesthesia, operative room environment, glycemic control, and Staphylococcus aureus nasal screening and decolonization. This article offers a road map for PJI prevention research.

  3. Calculations for reproducible autologous skin cell-spray grafting.

    Science.gov (United States)

    Esteban-Vives, Roger; Young, Matthew T; Zhu, Toby; Beiriger, Justin; Pekor, Chris; Ziembicki, Jenny; Corcos, Alain; Rubin, Peter; Gerlach, Jörg C

    2016-12-01

    Non-cultured, autologous cell-spray grafting is an alternative to mesh grafting for larger partial- and deep partial-thickness burn wounds. The treatment uses a suspension of isolated cells, from a patient's donor site skin tissue, and cell-spray deposition onto the wound that facilitates re-epithelialization. Existing protocols for therapeutic autologous skin cell isolation and cell-spray grafting have defined the donor site area to treatment area ratio of 1:80, substantially exceeding the coverage of conventional mesh grafting. However, ratios of 1:100 are possible by maximizing the wound treatment area with harvested cells from a given donor site skin tissue according to a given burn area. Although cell isolation methods are very well described in the literature, a rational approach addressing critical aspects of these techniques are of interest in planning clinical study protocols. We considered in an experimental study the cell yield as a function of the donor site skin tissue, the cell density for spray grafting, the liquid spray volume, the sprayed distribution area, and the percentage of surface coverage. The experimental data was then used for the development of constants and mathematical equations to give a rationale for the cell isolation and cell-spray grafting processes and in planning for clinical studies. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  4. Uncemented allograft-prosthetic composite reconstruction of the proximal femur

    Directory of Open Access Journals (Sweden)

    Li Min

    2014-01-01

    Full Text Available Background: Allograft-prosthetic composite can be divided into three groups names cemented, uncemented, and partially cemented. Previous studies have mainly reported outcomes in cemented and partially cemented allograft-prosthetic composites, but have rarely focused on the uncemented allograft-prosthetic composites. The objectives of our study were to describe a surgical technique for using proximal femoral uncemented allograft-prosthetic composite and to present the radiographic and clinical results. Materials and Methods: Twelve patients who underwent uncemented allograft-prosthetic composite reconstruction of the proximal femur after bone tumor resection were retrospectively evaluated at an average followup of 24.0 months. Clinical records and radiographs were evaluated. Results: In our series, union occurred in all the patients (100%; range 5-9 months. Until the most recent followup, there were no cases with infection, nonunion of the greater trochanter, junctional bone resorption, dislocation, allergic reaction, wear of acetabulum socket, recurrence, and metastasis. But there were three periprosthetic fractures which were fixed using cerclage wire during surgery. Five cases had bone resorption in and around the greater trochanter. The average Musculoskeletal Tumor Society (MSTS score and Harris hip score (HHS were 26.2 points (range 24-29 points and 80.6 points (range 66.2-92.7 points, respectively. Conclusions: These results showed that uncemented allograft-prosthetic composite could promote bone union through compression at the host-allograft junction and is a good choice for proximal femoral resection. Although this technology has its own merits, long term outcomes are yet not validated.

  5. Vascular graft infections with Mycoplasma

    DEFF Research Database (Denmark)

    Levi-Mazloum, Niels Donald; Skov Jensen, J; Prag, J

    1995-01-01

    laboratory techniques, the percentage of culture-negative yet grossly infected vascular grafts seems to be increasing and is not adequately explained by the prior use of antibiotics. We have recently reported the first case of aortic graft infection with Mycoplasma. We therefore suggest the hypothesis...... that the large number of culture-negative yet grossly infected vascular grafts may be due to Mycoplasma infection not detected with conventional laboratory technique....

  6. Prosthetic Mesh Repair for Incarcerated Inguinal Hernia

    Directory of Open Access Journals (Sweden)

    Cihad Tatar

    2016-08-01

    Full Text Available Background: Incarcerated inguinal hernia is a commonly encountered urgent surgical condition, and tension-free repair is a well-established method for the treatment of noncomplicated cases. However, due to the risk of prosthetic material-related infections, the use of mesh in the repair of strangulated or incarcerated hernia has often been subject to debate. Recent studies have demonstrated that biomaterials represent suitable materials for performing urgent hernia repair. Certain studies recommend mesh repair only for cases where no bowel resection is required; other studies, however, recommend mesh repair for patients requiring bowel resection as well. Aim: The aim of this study was to compare the outcomes of different surgical techniques performed for strangulated hernia, and to evaluate the effect of mesh use on postoperative complications. Study Design: Retrospective cross-sectional study. Methods: This retrospective study was performed with 151 patients who had been admitted to our hospital’s emergency department to undergo surgery for a diagnosis of incarcerated inguinal hernia. The patients were divided into two groups based on the applied surgical technique. Group 1 consisted of 112 patients treated with mesh-based repair techniques, while Group 2 consisted of 39 patients treated with tissue repair techniques. Patients in Group 1 were further divided into two sub-groups: one consisting of patients undergoing bowel resection (Group 3, and the other consisting of patients not undergoing bowel resection (Group 4. Results: In Group 1, it was observed that eight (7.14% of the patients had wound infections, while two (1.78% had hematomas, four (3.57% had seromas, and one (0.89% had relapse. In Group 2, one (2.56% of the patients had a wound infection, while three (7.69% had hematomas, one (2.56% had seroma, and none had relapses. There were no statistically significant differences between the two groups with respect to wound infection

  7. Re-operation for aortic and mitral prosthetic dysfunctions.

    Science.gov (United States)

    Kaul, T K; Sastry, M R; Mercer, J L; Meade, J B

    1985-01-01

    The overall incidence of re-operation and prosthetic valve endocarditis was low in the present series as mechanical prostheses were used predominantly. The prosthetic dysfunctions were less frequent following the primary implantation with Bjork Shiley prostheses, but high operative risk was associated with the clotted Bjork Shiley prostheses. We also had unusual experience of strut fracture and sticking of Bjork Shiley discs in the closed position in both aortic and mitral positions. The early deaths were nil since the use of cardioplegic protection. Intra-operative bleeding due to adhesions can be minimised by using synthetic or heterologous pericardium during the primary operation.

  8. Diagnostic flowcharts in osteomyelitis, spondylodiscitis and prosthetic joint infection

    International Nuclear Information System (INIS)

    Jutte, P.; Lazzeri, E.; Sconfienza, L. M.; Cassar-Pullicino, V.; Trampuz, A.; Petrosillo, N.; Signore, A.

    2014-01-01

    Infections of the bone, spine and prosthetic joints are serious and complex conditions to diagnose and to treat. Structured diagnostic workup may very well improve the accuracy and speed of diagnosis, thereby improving the outcome since treatment may very well be more successful and less harmful if timely management is started. Literature shows no uniform advise on diagnosis. The EANM organized a consensus meeting with representatives from the involved disciplines in order to develop common flowcharts for the diagnosis of osteomyelitis, spondylodiscitis and prosthetic joint infections. In this report the proceedings of this consensus meeting, including the proposed flowcharts for diagnosis, are published.

  9. The Effect of Platelet-Rich Plasma on Survival of the Composite Graft and the Proper Time of Injection in a Rabbit Ear Composite Graft Model

    Directory of Open Access Journals (Sweden)

    Hyun Nam Choi

    2014-11-01

    Full Text Available BackgroundAdministration of growth factors has been associated with increased viability of composite grafts greater than 1-cm in diameter. Platelet-rich plasma (PRP contains many of the growth factors studied. In this study, we evaluate the effect of PRP injection on composite graft viability and the proper time for injection.MethodsA total of 24 New Zealand White rabbits were divided into four groups. Autologous PRP was injected into the recipient sites three days before grafting in group 1, on the day of grafting in group 2, and three days after grafting in group 3. Group 4 served as control without PRP administration. Auricular composite grafts of 3-cm diameter were harvested and grafted back into place after being rotated 180 degrees. Median graft viability and microvessel density were evaluated at day 21 of graft via macroscopic photographs and immunofluorescent staining, respectively.ResultsThe median graft survival rate was 97.8% in group 1, 69.2% in group 2, 55.7% in group 3, and 40.8% in the control group. The median vessel counts were 34 (per ×200 HPF in group 1, 24.5 in group 2, 19.5 in group 3, and 10.5 in the control group.ConclusionsThis study demonstrates that PRP administration is associated with increased composite graft viability. All experimental groups showed a significantly higher survival rate and microvessel density, compared with the control group. Pre-administration of PRP was followed by the highest graft survival rate and revascularization. PRP treatments are minimally invasive, fast, easily applicable, and inexpensive, and offer a potential clinical pathway to larger composite grafts.

  10. Environmental application of radiation grafting

    International Nuclear Information System (INIS)

    Tamada, Masao

    2007-01-01

    Adsorbent having high selectivity against a certain metal ion was synthesized by means of radiation-induced graft polymerization for the purpose of environmental application. The resulting adsorbents were utilized for the removal of toxic metal from scallop waste and the collection of uranium from seawater. As a novel application of grafting, the biodegradability of poly-hydroxybutylate was controlled by grafting. The biodegradability could be depressed by the graft chain and then recovered by external stimuli such as thermal and chemical treatments. (author)

  11. Effects of prosthetic foot forefoot flexibility on oxygen cost and subjective preference rankings of unilateral transtibial prosthesis users.

    Science.gov (United States)

    Klodd, Elizabeth; Hansen, Andrew; Fatone, Stefania; Edwards, Mark

    2010-01-01

    The investigators conducted a double-blind randomized crossover study to determine the effects of prosthetic foot forefoot flexibility on oxygen cost and subjective preference rankings of 13 unilateral transtibial prosthesis users. Five experimental feet were fabricated for use in the study: F1, F2, F3, F4, and F5. F1 was most flexible, F5 was least flexible, and F3 was designed to conform to a biomimetic ankle-foot roll-over shape. The experimental feet were modeled after the Shape&Roll prosthetic foot (originally produced by Northwestern University, Chicago, Illinois; now in public domain) but had different numbers of saw cuts within the forefoot members, allowing more or less flexibility during walking. Participants walked at the same comfortable, freely selected speed on the treadmill for 7 min with each foot while energy expenditure was measured. No significant difference was found in oxygen cost (mL O(2)/kg/m) between the different feet (p = 0.17), and the order of use was also not significant (p = 0.94). However, the preference ranking was significantly affected by the flexibility of the feet (p = 0.002), with the most flexible foot (F1) ranking significantly poorer than feet F3 (p = 0.003) and F4 (p = 0.004). Users may prefer prosthetic feet that match the flexibility of an intact ankle-foot system, even though we did not detect an energetic benefit at freely selected speeds.

  12. Adapting to change: influence of a microprocessor-controlled prosthetic knee on gait adaptations

    NARCIS (Netherlands)

    Prinsen, Erik Christiaan

    2016-01-01

    Advancement in prosthetic knee design have led to the introduction of microprocessor-controlled prosthetic knees (MPKs). MPKs incorporate sensors that are able to measure prosthetic loading, the knee angle, and knee angular velocity. Based on the sensor information, MPKs determine the optimal level

  13. Pre-prosthetic surgical alterations in maxillectomy to enhance the prosthetic prognoses as part of rehabilitation of oral cancer patient.

    Science.gov (United States)

    El Fattah, H; Zaghloul, A; Pedemonte, E; Escuin, T

    2012-03-01

    After maxillectomy, prosthetic restoration of the resulting defect is an essential step because it signals the beginning of patient's rehabilitation. The obturator used to restore the defect should be comfortable, restore adequate speech, deglutition, mastication, and be cosmetically acceptable, success will depend on the size and location of the defect and the quantity and integrity of the remaining structures, in addition to pre-prosthetic surgical preparation of defect site. Preoperative cooperation between the oncologist surgeon and the maxillofacial surgeon may allow obturation of a resultant defect by preservation of the premaxilla or the tuberosity on the defect side and maintaining the alveolar bone or teeth adjacent to the defect. This study evaluates the importance of pre-prosthetic surgical alterations at the time maxillectomy on the enhancement of the prosthetic prognoses as part of the rehabilitation of oral cancer patient. The study was carried out between 2003- 2008, on 66 cancer patients(41 male-25 female) age ranged from 33 to 72 years, at National Cancer Institute, Cairo University, whom underwent maxillectomy surgery to remove malignant tumor as a part of cancer treatment. Patients were divided in two groups. Group A: Resection of maxilla followed by preprosthetic surgical preparation. Twenty-four cancer patients (13 male - 11 female). Group B: Resection of maxilla without any preprosthetic surgical preparation. Forty-two cancer patients (28 male-14 female). Outcome variables measured included facial contour and aesthetic results, speech understandability, ability to eat solid foods, oronasal separation, socializing outside the home, and return-to-work status. Flap success and donor site morbidity were also studied. To improve the prosthetic restoration of maxillary defect resulting maxillary resection as part treatment of maxillofacial tumor depends on the close cooperation between prosthodontist and surgeon, by combination of pre-prosthetic

  14. Grafting the alar rim: application as anatomical graft.

    Science.gov (United States)

    Gruber, Ronald P; Fox, Paige; Peled, Anne; Belek, Kyle A

    2014-12-01

    Alar rim contour and alar rim grafts have become essential components of rhinoplasty. Ideally, grafts of the nose should be anatomical in shape. So doing might make grafts of the alar rim more robust. The authors considered doing that by applying the graft as a continuous extension of the lateral crus. Twelve patients (two men and 10 women) constituted the study group (seven primary and five secondary cases). Of those, there were five concave rims, two concave rims with rim retraction, two boxy tips, and three cephalically oriented lateral crura. Surgical technique included the following: (1) an open approach was used; (2) a marginal incision that ignored the caudal margin of the lateral crus (the incision went straight posteriorly to a point 5 to 6 mm from the rim margin) was used; (3) a triangular graft was made to cover the exposed vestibular skin; (4) it was secured end to end to the caudal border of the lateral crus; and (5) the poster end was allowed to sit in a small subcutaneous pocket. Follow-up was 11 to 19 months. All 12 patients exhibited good rims as judged by a blinded panel. Rim retraction was not fully corrected in one patient, but no further treatment was required. One patient did require a secondary small rim graft for residual rim concavity. The concept of grafting the alar rim is strongly supported by the authors' results. The modifications the authors applied by designing the graft to be anatomical in shape has been a technical help.

  15. A dynamic model-based approach to motion and deformation tracking of prosthetic valves from biplane x-ray images.

    Science.gov (United States)

    Wagner, Martin G; Hatt, Charles R; Dunkerley, David A P; Bodart, Lindsay E; Raval, Amish N; Speidel, Michael A

    2018-04-16

    Transcatheter aortic valve replacement (TAVR) is a minimally invasive procedure in which a prosthetic heart valve is placed and expanded within a defective aortic valve. The device placement is commonly performed using two-dimensional (2D) fluoroscopic imaging. Within this work, we propose a novel technique to track the motion and deformation of the prosthetic valve in three dimensions based on biplane fluoroscopic image sequences. The tracking approach uses a parameterized point cloud model of the valve stent which can undergo rigid three-dimensional (3D) transformation and different modes of expansion. Rigid elements of the model are individually rotated and translated in three dimensions to approximate the motions of the stent. Tracking is performed using an iterative 2D-3D registration procedure which estimates the model parameters by minimizing the mean-squared image values at the positions of the forward-projected model points. Additionally, an initialization technique is proposed, which locates clusters of salient features to determine the initial position and orientation of the model. The proposed algorithms were evaluated based on simulations using a digital 4D CT phantom as well as experimentally acquired images of a prosthetic valve inside a chest phantom with anatomical background features. The target registration error was 0.12 ± 0.04 mm in the simulations and 0.64 ± 0.09 mm in the experimental data. The proposed algorithm could be used to generate 3D visualization of the prosthetic valve from two projections. In combination with soft-tissue sensitive-imaging techniques like transesophageal echocardiography, this technique could enable 3D image guidance during TAVR procedures. © 2018 American Association of Physicists in Medicine.

  16. Suction blister grafting - Modifications for easy harvesting and grafting

    Directory of Open Access Journals (Sweden)

    2012-01-01

    Full Text Available Suction blister grafting is a simple modality of treatment of patients with resistant and stable vitiligo. But raising the blisters may be time consuming and transferring to the recipient site may be difficult as the graft is ultrathin. By doing some modifications we can make the technique simpler and easier. We can decrease the blister induction time by intradermal injection of saline, exposure to Wood′s lamp, intrablister injection of saline. By these methods we can decrease the blister induction time from 2-3 hrs to 45-90 minutes. After harvesting the graft, it can be transferred to the recipient area by taking the graft on a sterile glass slide, on the gloved finger, rolling the graft over a sterile syringe and then spreading on the recipient area, or taking on the sterile wrapper of paraffin dressing and then placing over the recipient area.

  17. [Vacuum sealing drainage combined with free skin graft in repairing cutaneous deficiency of traumatic shank amputation stump].

    Science.gov (United States)

    Zhao, Xiao-fei; Li, Chun-you; Jin, Guo-qiang; Ming, Xiao-feng; Wang, Guo-jie

    2014-12-01

    To observe clinical efficacy in treating cutaneous deficiency of traumatic shank amputation stump with full-thickness skin graft combined with vacuum sealing drainage. From September 2009 to December 2012, 15 patients with cutaneous deficiency of traumatic shank amputation stump were treated with full-thickness skin graft combined with vacuum sealing drainage. Among patients, there were 11 males and 4 females with an average age of 41.5 (ranged from 25 to 62) years old. Ten cases were caused by traffic accident and 5 cases were caused by heavy object, 9 cases on left and 6 cases on right. Six patients with smashed wound were treated with debridement and amputation, combined with vacuum aspiration in-emergency; 9 patients caused by infection and necrosis were treated with debridement and amputation, combined with vacuum aspiration, and full-thickness skin graft were performed at stage II. The skin defect area of residual limbs ranged from 40 cm x 20 cm to 25 cm x 15 cm. All patients were followed up from 3 months to 1 year. Full-thickness skin graft of residual limbs were survived,and obtained satisfactory walking function with prosthetic. Residual skin increased thicken, wearproof without rupture and pain. Full-thickness skin graft combined with vacuum sealing drainage in treating cutaneous deficiency of traumatic shank amputation stump could reserve the length of residual limbs, increase survival rate of skin graft with less scar of survival skin, get good wearability and it is conducive to prosthetic wear. It is a simple and easy treatment method.

  18. Early prosthetic valve endocarditis caused by Corynebacterium kroppenstedtii.

    Science.gov (United States)

    Hagemann, Jürgen Benjamin; Essig, Andreas; Herrmann, Manuel; Liebold, Andreas; Quader, Mohamed Abo

    2015-12-01

    Corynebacterium (C.) kroppenstedtii is a rarely detected agent of bacterial infections in humans. Here, we describe the first case of prosthetic valve endocarditis caused by C. kroppenstedtii. Application of molecular methods using surgically excised valve tissue was a cornerstone for the establishment of the microbiological diagnosis, which is crucial for targeted antimicrobial treatment. Copyright © 2015 Elsevier GmbH. All rights reserved.

  19. Development of a 3D-Printed Robotic Prosthetic Arm

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Martinez, M.; Garcia-Miquel, A.; Vidal Martinez, N.

    2016-07-01

    Current prostheses are not affordable to the general public. 3D printing technology may allow low-cost production of such devices, making them more readily accessible to people in need. This contribution presents the set-up and the considerations that have to be taken into account to develop a functional artificial upper limb prototype. The robotic prosthetic arm reported herein was produced entirely using 3D printing technology to demonstrate its feasibility on a limited budget. The project was developed to integrate two different functional modes: a prosthetic application and a remote application. The prosthetic application is intended to emulate existing prosthetic devices using myoelectric sensors. The remote application is conceived as a tool for prevention, by providing the general public with a device that could carry out activities that entail a risk of severe physical injury. This is achieved using a hand-tracking system that allows the robotic arm to copy the user’s movements remotely and in real time. The outcome of the validation tests has been considerably successful for both applications and the total costs are on target. (Author)

  20. Consumer satisfaction with the services of prosthetics and orthotics facilities

    NARCIS (Netherlands)

    Bosmans, Joline; Geertzen, Jan; Dijkstra, Pieter U.

    2009-01-01

    Consumer satisfaction with the services provided in a prosthetics and orthotics (PO) facility has seldom been studied. The aim of this study was to analyze consumer satisfaction regarding the services provided by 15 PO facilities in The Netherlands. Consumers (n=1,364) of these PO facilities who

  1. Role of CT in patients with prosthetic heart valves

    NARCIS (Netherlands)

    Suchá, D.

    2016-01-01

    Valvular heart disease accounts for a substantial part of the cardiovascular disease worldwide with an estimated prevalence of 2.5% in the Western population aged <65 years and over 13% in the population aged >75 years. Surgical prosthetic heart valve (PHV) replacement is the indicated therapy for

  2. Esthetics with prosthetics in case of maxillary canine transposition: A ...

    African Journals Online (AJOL)

    Esthetics with prosthetics in case of maxillary canine transposition: A clinical report. ... provides a helpful Frequently Asked Questions about PDFs. Alternatively, you can download the PDF file directly to your computer, from where it can be opened using a PDF reader. To download the PDF, click the Download link above.

  3. Determining asymmetry of roll-over shapes in prosthetic walking

    NARCIS (Netherlands)

    Curtze, C.; Otten, Bert; Hof, A.L.; Postema, K.

    2011-01-01

    How does the inherent asymmetry of the locomotor system in people with lower-limb amputation affect the ankle-foot roll-over shape of prosthetic walking? In a single-case design, we evaluated the walking patterns of six people with lower-limb amputation (3 transtibial and 3 transfemoral) and three

  4. Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

    NARCIS (Netherlands)

    Habets, Jesse; Budde, Ricardo P.; Symersky, Petr; van den Brink, Renee B.; de Mol, Bas A.; Mali, Willem P.; van Herwerden, Lex A.; Chamuleau, Steven A.

    Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these

  5. Diagnostic evaluation of left-sided prosthetic heart valve dysfunction

    NARCIS (Netherlands)

    Habets, Jesse; Budde, Ricardo P.; Symersky, Petr; van den Brink, Renee B.; de Mol, Bas A.; Mali, Willem P.; van Herwerden, Lex A.; Chamuleau, Steven A.

    2011-01-01

    Prosthetic heart valve (PHV) dysfunction is a rare, but potentially life-threatening, complication. In clinical practice, PHV dysfunction poses a diagnostic dilemma. Echocardiography and fluoroscopy are the imaging techniques of choice and are routinely used in daily practice. However, these

  6. Development of a prototype over-actuated biomimetic prosthetic hand.

    Directory of Open Access Journals (Sweden)

    Matthew R Williams

    Full Text Available The loss of a hand can greatly affect quality of life. A prosthetic device that can mimic normal hand function is very important to physical and mental recuperation after hand amputation, but the currently available prosthetics do not fully meet the needs of the amputee community. Most prosthetic hands are not dexterous enough to grasp a variety of shaped objects, and those that are tend to be heavy, leading to discomfort while wearing the device. In order to attempt to better simulate human hand function, a dexterous hand was developed that uses an over-actuated mechanism to form grasp shape using intrinsic joint mounted motors in addition to a finger tendon to produce large flexion force for a tight grip. This novel actuation method allows the hand to use small actuators for grip shape formation, and the tendon to produce high grip strength. The hand was capable of producing fingertip flexion force suitable for most activities of daily living. In addition, it was able to produce a range of grasp shapes with natural, independent finger motion, and appearance similar to that of a human hand. The hand also had a mass distribution more similar to a natural forearm and hand compared to contemporary prosthetics due to the more proximal location of the heavier components of the system. This paper describes the design of the hand and controller, as well as the test results.

  7. Diagnostic flowcharts in osteomyelitis, spondylodiscitis and prosthetic joint infection

    NARCIS (Netherlands)

    Jutte, P.; Lazzeri, E.; Sconfienza, L. M.; Cassar-Pullicino, V.; Trampuz, A.; Petrosillo, N.; Signore, A.

    Infections of the bone, spine and prosthetic joints are serious and complex conditions to diagnose and to treat. Structured diagnostic workup may very well improve the accuracy and speed of diagnosis, thereby improving the outcome since treatment may very well be more successful and less harmful if

  8. Effect of Modifying Prosthetic Socket Base Materials by Adding Nanodiamonds

    Directory of Open Access Journals (Sweden)

    Lifang Ma

    2015-01-01

    Full Text Available The curing process of prosthetic socket base materials requires attention owing to a series of associated problems that are yet to be addressed and solved. However, to date, few relevant studies have been reported. In this paper, nanodiamonds modified with a silane coupling agent were dispersed into a prosthetic socket base material, and the performance of the modified base materials was investigated. Adding a predetermined amount of nanodiamonds to the prosthetic socket base material increased the glass transition temperature, improved the mechanical properties of the cured base material, and reduced the influence of the volatile gas formed during the curing process on the environment. With increasing nanodiamond contents, the glass transition temperature increased and the mechanical properties improved slightly. Owing to the high thermal conductivity of the nanodiamonds, the localized heat, as a result of the curing process, could be dissipated and released. Thus, adding nanodiamonds led to a more uniform temperature field forming in the curing system. This improved the curing process and reduced the formation of volatile monomers, thereby decreasing the adverse impact of the generated volatile gases on the environment. All of these provide a potential strategy for modifying prosthetic socket base materials.

  9. Prosthetic prescription in the Netherlands : an observational study

    NARCIS (Netherlands)

    van der Linde, H; Geertzen, JHB; Hofstad, CJ; Postema, K; Van Limbeek, Jacques

    2003-01-01

    Prosthetic prescription for lower limb amputees and the methodology used are primarily based on empirical knowledge. Clinical expertise plays an important role that can lead to an adequate prescription; however, a clear evidence based motivation for the choices made cannot be given. This can lead to

  10. SOME TECHNIQUES IN CORNEAL GRAFTING

    African Journals Online (AJOL)

    1971-04-10

    Apr 10, 1971 ... current herpes corneae. The visual acuity was less than. 6/60. The left eye had had a central nebula since child- hood and was deemed amblyopic. Six weeks after a 7 x 0·3 mm lamellar graft in the right eye was placed, ulceration occurred in the graft junction. A total thin conjunctival flap was sutured over.

  11. Polyether/Polyester Graft Copolymers

    Science.gov (United States)

    Bell, Vernon L., Jr.; Wakelyn, N.; Stoakley, D. M.; Proctor, K. M.

    1986-01-01

    Higher solvent resistance achieved along with lower melting temperature. New technique provides method of preparing copolymers with polypivalolactone segments grafted onto poly (2,6-dimethyl-phenylene oxide) backbone. Process makes strong materials with improved solvent resistance and crystalline, thermally-reversible crosslinks. Resulting graft copolymers easier to fabricate into useful articles, including thin films, sheets, fibers, foams, laminates, and moldings.

  12. A comparison of patency and interventions in thigh versus Hemodialysis Reliable Outflow grafts for chronic hemodialysis vascular access.

    Science.gov (United States)

    Brownie, Evan R; Kensinger, Clark D; Feurer, Irene D; Moore, Derek E; Shaffer, David

    2016-11-01

    With improvements in medical management and survival of patients with end-stage renal disease, maintaining durable vascular access is increasingly challenging. This study compared primary, assisted primary, and secondary patency, and procedure-specific complications, and evaluated whether the number of interventions to maintain or restore patency differed between prosthetic femoral-femoral looped inguinal access (thigh) grafts and Hemodialysis Reliable Outflow (HeRO; Hemosphere Inc, Minneapolis, Minn) grafts. A single-center, retrospective, intention-to-treat analysis was conducted of consecutive thigh and HeRO grafts placed between May 2004 and June 2015. Medical history, interventions to maintain or restore patency, and complications were abstracted from the electronic medical record. Data were analyzed using parametric and nonparametric statistical tests, Kaplan-Meier survival methods, and multivariable proportional hazards regression and logistic regression. Seventy-six (43 thigh, 33 HeRO) grafts were placed in 61 patients (54% male; age 53 [standard deviation, 13] years). Median follow-up time in the intention-to-treat analysis was 21.2 months (min, 0.0; max, 85.3 months) for thigh grafts and 6.7 months (min, 0.0; max, 56.3 months) for HeRO grafts (P = .02). The groups were comparable for sex, age, coronary artery disease, diabetes mellitus, peripheral vascular disease, and smoking history (all P ≥ .12). One thigh graft (2%) and five HeRO (15%) grafts failed primarily. In the intention-to-treat analysis, patency durations were significantly longer in the thigh grafts (all log-rank P ≤ .01). Point estimates of primary patency at 6 months, 1 year, and 3 years were 61%, 46%, and 4% for the thigh grafts and 25%, 15%, and 6% for the HeRO grafts. Point estimates of assisted primary patency at 6 months, 1 year, and 3 years were 75%, 66%, and 54% for the thigh grafts and 41%, 30%, and 10% for the HeRO grafts. Point estimates of secondary patency at 6

  13. Effects of prosthetic foot forefoot flexibility on oxygen cost and subjective preference rankings of unilateral transtibial prosthesis users

    OpenAIRE

    Mark Edwards, MHPE, CP; Stefania Fatone, PhD; Andrew Hansen, PhD; Elizabeth Klodd, MS

    2010-01-01

    The investigators conducted a double-blind randomized crossover study to determine the effects of prosthetic foot forefoot flexibility on oxygen cost and subjective preference rankings of 13 unilateral transtibial prosthesis users. Five experimental feet were fabricated for use in the study: F1, F2, F3, F4, and F5. F1 was most flexible, F5 was least flexible, and F3 was designed to conform to a biomimetic ankle-foot roll-over shape. The experimental feet were modeled after the Shape&Roll pros...

  14. Quality Assessment of Prosthetic Rehabilitation Using Aesthetic Fixed Restorations

    Directory of Open Access Journals (Sweden)

    Zinovii Ozhohan

    2018-04-01

    Full Text Available The objective of the research was to study and assess the quality of prosthetic treatment using aesthetic fixed restorations. Materials and methods. The study included 79 patients without a comorbidity who underwent prosthetic rehabilitation. All the patients were divided into 3 groups: Group I included 25 patients with metal-plastic restorations; Group II comprised 34 patients with porcelain-fused-to-metal restorations; Group III consisted of 20 patients with a combined occlusal surface of prosthetic restorations. The patients were observed 6 months after prosthetic repair. Only patients with single molar and premolar crowns were examined. Bridge prostheses were not taken into account in order to eliminate the effect of masticatory force redistribution on the abutment crowns. Results. In Group I, 11 (44% patients were satisfied with the results of prosthetic treatment. In Group II, 25 (78.12% patients reported that they were satisfied with their treatment. In Group III, there were 17 (85% patients satisfied with their outcome. However, the patients’ complaints are often subjective and do not fully reflect the objective state of the dentoalveolar system. An objective examination revealed that in indirect restorations, marginal periodontium pathology is typical. Conclusions. Aesthetic fixed restorations with a combined occlusal surface have demonstrated good clinical results, even at long-term follow-up. Combining positive properties of two different construction materials, namely zirconium dioxide and ceramics, they reduce the risk of complications such as marginal periodontium pathology and chipping along the occlusal surface as well as contribute to minimal abrasion of the occlusal surfaces of the antagonistic teeth. We cannot recommend metal-plastic restorations due to their low clinical effectiveness, poor aesthetic qualities as well as a high level of marginal periodontium pathology.

  15. Evaluation of 3D printed anatomically scalable transfemoral prosthetic knee.

    Science.gov (United States)

    Ramakrishnan, Tyagi; Schlafly, Millicent; Reed, Kyle B

    2017-07-01

    This case study compares a transfemoral amputee's gait while using the existing Ossur Total Knee 2000 and our novel 3D printed anatomically scalable transfemoral prosthetic knee. The anatomically scalable transfemoral prosthetic knee is 3D printed out of a carbon-fiber and nylon composite that has a gear-mesh coupling with a hard-stop weight-actuated locking mechanism aided by a cross-linked four-bar spring mechanism. This design can be scaled using anatomical dimensions of a human femur and tibia to have a unique fit for each user. The transfemoral amputee who was tested is high functioning and walked on the Computer Assisted Rehabilitation Environment (CAREN) at a self-selected pace. The motion capture and force data that was collected showed that there were distinct differences in the gait dynamics. The data was used to perform the Combined Gait Asymmetry Metric (CGAM), where the scores revealed that the overall asymmetry of the gait on the Ossur Total Knee was more asymmetric than the anatomically scalable transfemoral prosthetic knee. The anatomically scalable transfemoral prosthetic knee had higher peak knee flexion that caused a large step time asymmetry. This made walking on the anatomically scalable transfemoral prosthetic knee more strenuous due to the compensatory movements in adapting to the different dynamics. This can be overcome by tuning the cross-linked spring mechanism to emulate the dynamics of the subject better. The subject stated that the knee would be good for daily use and has the potential to be adapted as a running knee.

  16. Radiation grafting on natural films

    Science.gov (United States)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37-40 N mm-1) and puncture deformation (PD=6.5-9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282-296 N mm-1 and PD of 5.0-5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films.

  17. Robotic hand with locking mechanism using TCP muscles for applications in prosthetic hand and humanoids

    Science.gov (United States)

    Saharan, Lokesh; Tadesse, Yonas

    2016-04-01

    This paper presents a biomimetic, lightweight, 3D printed and customizable robotic hand with locking mechanism consisting of Twisted and Coiled Polymer (TCP) muscles based on nylon precursor fibers as artificial muscles. Previously, we have presented a small-sized biomimetic hand using nylon based artificial muscles and fishing line muscles as actuators. The current study focuses on an adult-sized prosthetic hand with improved design and a position/force locking system. Energy efficiency is always a matter of concern to make compact, lightweight, durable and cost effective devices. In natural human hand, if we keep holding objects for long time, we get tired because of continuous use of energy for keeping the fingers in certain positions. Similarly, in prosthetic hands we also need to provide energy continuously to artificial muscles to hold the object for a certain period of time, which is certainly not energy efficient. In this work we, describe the design of the robotic hand and locking mechanism along with the experimental results on the performance of the locking mechanism.

  18. Design, Sensing and Control of a Robotic Prosthetic Eye for Natural Eye Movement

    Directory of Open Access Journals (Sweden)

    J. J. Gu

    2006-01-01

    Full Text Available Loss of an eye is a tragedy for a person, who may suffer psychologically and physically. This paper is concerned with the design, sensing and control of a robotic prosthetic eye that moves horizontally in synchronization with the movement of the natural eye. Two generations of robotic prosthetic eye models have been developed. The first generation model uses an external infrared sensor array mounted on the frame of a pair of eyeglasses to detect the natural eye movement and to feed the control system to drive the artificial eye to move with the natural eye. The second generation model removes the impractical usage of the eye glass frame and uses the human brain EOG (electro-ocular-graph signal picked up by electrodes placed on the sides of a person's temple to carry out the same eye movement detection and control tasks as mentioned above. Theoretical issues on sensor failure detection and recovery, and signal processing techniques used in sensor data fusion, are studied using statistical methods and artificial neural network based techniques. In addition, practical control system design and implementation using micro-controllers are studied and implemented to carry out the natural eye movement detection and artificial robotic eye control tasks. Simulation and experimental studies are performed, and the results are included to demonstrate the effectiveness of the research project reported in this paper.

  19. Virtual Constraint Control of a Powered Prosthetic Leg: From Simulation to Experiments with Transfemoral Amputees.

    Science.gov (United States)

    Gregg, Robert D; Lenzi, Tommaso; Hargrove, Levi J; Sensinger, Jonathon W

    2014-12-01

    Recent powered (or robotic) prosthetic legs independently control different joints and time periods of the gait cycle, resulting in control parameters and switching rules that can be difficult to tune by clinicians. This challenge might be addressed by a unifying control model used by recent bipedal robots, in which virtual constraints define joint patterns as functions of a monotonic variable that continuously represents the gait cycle phase. In the first application of virtual constraints to amputee locomotion, this paper derives exact and approximate control laws for a partial feedback linearization to enforce virtual constraints on a prosthetic leg. We then encode a human-inspired invariance property called effective shape into virtual constraints for the stance period. After simulating the robustness of the partial feedback linearization to clinically meaningful conditions, we experimentally implement this control strategy on a powered transfemoral leg. We report the results of three amputee subjects walking overground and at variable cadences on a treadmill, demonstrating the clinical viability of this novel control approach.

  20. Allogeneic bone marrow grafts in genotyped swine

    International Nuclear Information System (INIS)

    Vaiman, M.

    1974-01-01

    The proof of a major histocompatibility complex (MHC) called SL-A enabled to promote bone marrow allografts. A study of the response to that kind of graft in irradiated pig states a number of interesting points. Bone marrow allografting complies with the rule of tissular compatibility with the major histocompatibility complex. The taking of SL-A incompatible bone marrow allografts could not be achieved under the experimental conditions. In spite of the high doses of radiation, 950 to 1050 rads, higher than 1.5 LD 100%, recipients were capable of rejecting their grafts, regularly. SL-A identify ensured 100%, initial achievement. However, animals developed regular fatal disease within a fairly short time. This development could by no means, be ascribed to the sole sequealae of radiation sickness since autografted animals at equal or even higher doses, showed none of the symptome. Assumption of a chronic graft-vs-host reactions, induced by the minor histocompatible systems, was put foreward, but should be confirmed histopathologically [fr

  1. Dutch evidence-based guidelines for amputation and prosthetics of the lower extremity : Rehabilitation process and prosthetics. Part 2

    NARCIS (Netherlands)

    Geertzen, Jan; van der Linde, Harmen; Rosenbrand, Kitty; Conradi, Marcel; Deckers, Jos; Koning, Jan; Rietman, Hans S.; van der Schaaf, Dick; van der Ploeg, Rein; Schapendonk, Johannes; Schrier, Ernst; Duijzentkunst, Rob Smit; Spruit-van Eijk, Monica; Versteegen, Gerbrig; Voesten, Harrie

    2015-01-01

    Background: A structured, multidisciplinary approach in the rehabilitation process after amputation is needed that includes a greater focus on the involvement of both (para)medics and prosthetists. There is considerable variation in prosthetic prescription concerning the moment of initial prosthesis

  2. Neointima development in externally stented saphenous vein grafts

    Directory of Open Access Journals (Sweden)

    Przemysław Węglarz

    2016-11-01

    Full Text Available Introduction : The main limitation of coronary artery bypass grafting (CABG is rapid neointimal hyperplasia leading to graft failure. Aim : To assess plaque formation in saphenous vein grafts (SVG covered by an external Dacron stent in comparison with the classical technique. Material and methods : In the study group vein grafts covered by external stent mesh made of Dacron were implanted. An intravascular ultrasonography (IVUS study was performed in 35 aorto-coronary SVG covered by an external Dacron stent and in 64 normal SVG during the first year after CABG. In each SVG 25 mm of good quality IVUS image, volumes of lumen, plaque (neointima, outer border of the vein graft (external SVG and adventitia were calculated in three time periods: 0–130 days, 130–260 days and 260–390 days. Results : Between the first and second time period, lumen volume (mm3 was reduced from 10.33 ±4.4, to 6.80 ±2.23 in the second period and 5.69 ±1.26 in the third one. This effect was much less marked in normal grafts. The corresponding lumen volume (mm3 was: 10.90 ±3.9, 9.15 ±2.94 and 8.92 ±2.93 in consecutive time periods. Plaque volume (mm3 did not change in control grafts during the course of the study, but it increased very significantly in stented grafts from 0.86 ±1.24 in the first period to 2.70 ±1.58 in the second and 3.29 ±2.66 in the third one. Conclusions : The experimental technique of implanting SVG covered with an external elastic Dacron stent seems to be inferior to traditional ones. This is probably due to the more complicated process of vein implantation and higher micro-injury occurrence during the surgery.

  3. Graft intolerance syndrome requiring graft nephrectomy after late kidney graft failure: can it be predicted? A retrospective cohort study.

    Science.gov (United States)

    Bunthof, Kim L W; Verhoeks, Carmen M; van den Brand, Jan A J G; Hilbrands, Luuk B

    2018-02-01

    Graft nephrectomy is recommended in case of early graft failure. When the graft fails more than 3-6 months after transplantation, it is current practice to follow a wait-and-see policy. A common indication for graft removal is the graft intolerance syndrome. We aimed to create a risk prediction model for the occurrence of graft intolerance resulting in graft nephrectomy. We collected data of kidney transplantations performed in our center between 1980 and 2010 that failed at least 6 months after transplantation. We evaluated the association between baseline characteristics and the occurrence of graft nephrectomy because of graft intolerance using a competing risk regression model. Prognostic factors were included in a multivariate prediction model. In- and exclusion criteria were met in 288 cases. In 48 patients, the graft was removed because of graft intolerance. Donor age, the number of rejections, and shorter graft survival were predictive factors for graft nephrectomy because of the graft intolerance syndrome. These factors were included in a prediction rule. Using donor age, graft survival, and the number of rejections, clinicians can predict the need for graft nephrectomy with a reasonable accuracy. © 2017 Steunstichting ESOT.

  4. Initial Clinical Evaluation of the Modular Prosthetic Limb

    Directory of Open Access Journals (Sweden)

    Briana N. Perry

    2018-03-01

    Full Text Available The Modular Prosthetic Limb (MPL was examined for its feasibility and usability as an advanced, dexterous upper extremity prosthesis with surface electromyography (sEMG control in with two individuals with below-elbow amputations. Compared to currently marketed prostheses, the MPL has a greater number of sequential and simultaneous degrees of motion, as well as wrist modularity, haptic feedback, and individual digit control. The MPL was successfully fit to a 33-year-old with a trans-radial amputation (TR01 and a 30-year-old with a wrist disarticulation amputation (TR02. To preserve anatomical limb length, we adjusted the powered degrees of freedom of wrist motion between users. Motor training began with practicing sEMG and pattern recognition control within the virtual integration environment (VIE. Prosthetic training sessions then allowed participants to complete a variety of activities of daily living with the MPL. Training and Motion Control Accuracy scores quantified their ability to consistently train and execute unique muscle-to-motion contraction patterns. Each user also completed one prosthetic functional metric—the Southampton Hand Assessment Procedure (SHAP for TR01 and the Jebsen-Taylor Hand Function Test (JHFT for TR02. Haptic feedback capabilities were integrated for TR01. TR01 achieved 95% accuracy at 84% of his VIE sessions. He demonstrated improved scores over a year of prosthetic training sessions, ultimately achieving simultaneous control of 13 of the 17 (76% attempted motions. His performance on the SHAP improved from baseline to final assessment with an increase in number of tasks achieved. TR01 also used vibrotactile sensors to successfully discriminate between hard and soft objects being grasped by the MPL hand. TR02 demonstrated 95% accuracy at 79% of his VIE sessions. He demonstrated improved scores over months of prosthetic training sessions, however there was a significant drop in scores initially following a mid

  5. Cartilage grafting in nasal reconstruction.

    Science.gov (United States)

    Immerman, Sara; White, W Matthew; Constantinides, Minas

    2011-02-01

    Nasal reconstruction after resection for cutaneous malignancies poses a unique challenge to facial plastic surgeons. The nose, a unique 3-D structure, not only must remain functional but also be aesthetically pleasing to patients. A complete understanding of all the layers of the nose and knowledge of available cartilage grafting material is necessary. Autogenous material, namely septal, auricular, and costal cartilage, is the most favored material in a free cartilage graft or a composite cartilage graft. All types of material have advantages and disadvantages that should guide the most appropriate selection to maximize the functional and cosmetic outcomes for patients. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. Inheritance of graft compatibility in Douglas fir.

    Science.gov (United States)

    D.L. Copes

    1973-01-01

    Graft compatibility of genetically related and unrelated rootstock-scion combinations was compared. Scion clones were 75% compatible when grafted on half-related rootstocks but only 56% compatible when grafted on unrelated rootstocks. Most variance associated with graft incompatibility in Douglas-fir appears to be caused by multiple genes.

  7. Graft union formation in Douglas-fir.

    Science.gov (United States)

    D.L. Copes

    1969-01-01

    Greenhouse-grown Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) graft unions were examined between 2 and 84 days after grafting. Room temperature was maintained at 60-70 F throughout the growing season. In most respects grafts of Douglas-fir followed development patterns previously reported for spruce and pine grafts, but specific differences...

  8. Vascularized bone grafting in a canine carpal avascular necrosis model

    NARCIS (Netherlands)

    Willems, Wouter F.; Alberton, Gregory M.; Bishop, Allen T.; Kremer, Thomas

    2011-01-01

    Limited experimental research has been performed on the treatment of avascular necrosis (AVN) by vascularized bone grafting. A new model simulating carpal AVN was created to investigate surgical revascularization of necrotic bone. In seven mongrel dogs, AVN was induced by removal of the radial

  9. Fat Grafting for Facial Filling and Regeneration.

    Science.gov (United States)

    Coleman, Sydney R; Katzel, Evan B

    2015-07-01

    Plastic surgeons have come to realize that fat grafting can rejuvenate an aging face by restoring or creating fullness. However, fat grafting does much more than simply add volume. Grafted fat can transform or repair the tissues into which it is placed. Historically, surgeons have hesitated to embrace the rejuvenating potential of fat grafting because of poor graft take, fat necrosis, and inconsistent outcomes. This article describes fat grafting techniques and practices to assist readers in successful harvesting, processing, and placement of fat for optimal graft retention and facial esthetic outcomes. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Design of a Sapling Branch Grafting Robot

    Directory of Open Access Journals (Sweden)

    Qun Sun

    2014-01-01

    Full Text Available The automatic sapling grafting methods and grafting robot technologies are not comprehensively studied despite the fact that they are urgently required in practice. For this reason, a sapling grafting robot is developed to implement automatic grafting for saplings. The developed grafting robot includes clipping mechanism, moving mechanism, cutting mechanism, binding mechanism, and Arduino MCU based control system, which is capable of clipping, moving, positioning, cutting, grafting, and binding saplings. Experiments show that the stock cutting efficiency is 98.4%, the scion cutting efficiency is 98.9%, the grafting efficiency is 87.3%, and the binding efficiency is 68.9%.

  11. Reconstruction of the maxilla following hemimaxillectomy defects with scapular tip grafts and dental implants.

    Science.gov (United States)

    Mertens, Christian; Freudlsperger, Christian; Bodem, Jens; Engel, Michael; Hoffmann, Jürgen; Freier, Kolja

    2016-11-01

    Treatment of post-resective defects of the maxilla can be challenging and usually requires dental obturation or microvascular reconstruction. As compared to soft-tissue microvascular grafts, bone reconstruction can additionally allow for facial support and retention of dental implants. The aim of this study was to evaluate scapular tip grafts with respect to their applicability for maxillary reconstruction and their potential to retain dental implants for later dental rehabilitation. In this retrospective study, 14 patients with hemimaxillectomy defects were reconstructed with free scapular tip grafts, oriented horizontally, to rebuild the palate and alveolar ridge. After bone healing, three-dimensional virtual implant planning was performed, and a radiographic guide was fabricated to enable implant placement in the optimal anatomic and prosthetic position. All patients' mastication and speech were evaluated, along with the extent of defect closure, suitability of the graft sites for implant placement, and soft-tissue stability. Pre- and postsurgical radiographs were also evaluated. A good postoperative outcome was achieved in all patients, with complete closure of maxillary defects that were class II, according to the system of Brown and Shaw. Additional bone augmentation was necessary in two patients in order to increase vertical bone height. Patients were subsequently treated with 50 dental implants to retain dental prostheses. In all cases, additional soft-tissue surgery was necessary to achieve a long-term stable periimplant situation. No implants were lost during the mean observation period of 34 months. Due to its specific form, the scapular tip graft is well suited to reconstruct the palate and maxillary alveolar ridge and to enable subsequent implant-retained rehabilitation. Due to the limited bone volume, an accurate three-dimensional graft orientation is essential. Furthermore, most cases require additional soft-tissue surgery to achieve a long

  12. A highly selective sorbent for removal of Cr(VI) from aqueous solutions based on Fe{sub 3}O{sub 4}/poly(methyl methacrylate) grafted Tragacanth gum nanocomposite: Optimization by experimental design

    Energy Technology Data Exchange (ETDEWEB)

    Sadeghi, Susan, E-mail: ssadeghi@birjand.ac.ir; Rad, Fatemeh Alavi; Moghaddam, Ali Zeraatkar

    2014-12-01

    In this work, poly(methyl methacrylate) grafted Tragacanth gum modified Fe{sub 3}O{sub 4} magnetic nanoparticles (P(MMA)-g-TG-MNs) were developed for the selective removal of Cr(VI) species from aqueous solutions in the presence of Cr(III). The sorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), a vibrating sample magnetometer (VSM), and thermo-gravimetric analysis (TGA). A screening study on operational variables was performed using a two-level full factorial design. Based on the analysis of variance (ANOVA) with 95% confidence limit, the significant variables were found. The central composite design (CCD) has also been employed for statistical modeling and analysis of the effects and interactions of significant variables dealing with the Cr(VI) uptake process by the developed sorbent. The predicted optimal conditions were situated at a pH of 5.5, contact time of 3.4 h, and 3.0 g L{sup −1} dose. The Langmuir, Freundlich, and Temkin isotherm models were used to describe the equilibrium sorption of Cr(VI) by the absorbent, and the Langmuir isotherm showed the best concordance as an equilibrium model. The adsorption process was followed by a pseudo-second-order kinetic model. Thermodynamic investigations showed that the biosorption process was spontaneous and exothermic. - Highlights: • Fe3O4 nanoparticles were modified with Poly(methyl methacrylate) grafted Tragacanth gum • P(MMA)-g-TG -MNPs can preferentially adsorb Cr(VI) in the presence of Cr(III) • The effects of operational parameters on Cr(VI) removal were evaluated by RSM • Adsorption mechanism, kinetics, and isotherm have been explored • The sorbent was successfully used to remove Cr(VI) from different water samples.

  13. A highly selective sorbent for removal of Cr(VI) from aqueous solutions based on Fe3O4/poly(methyl methacrylate) grafted Tragacanth gum nanocomposite: Optimization by experimental design

    International Nuclear Information System (INIS)

    Sadeghi, Susan; Rad, Fatemeh Alavi; Moghaddam, Ali Zeraatkar

    2014-01-01

    In this work, poly(methyl methacrylate) grafted Tragacanth gum modified Fe 3 O 4 magnetic nanoparticles (P(MMA)-g-TG-MNs) were developed for the selective removal of Cr(VI) species from aqueous solutions in the presence of Cr(III). The sorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), a vibrating sample magnetometer (VSM), and thermo-gravimetric analysis (TGA). A screening study on operational variables was performed using a two-level full factorial design. Based on the analysis of variance (ANOVA) with 95% confidence limit, the significant variables were found. The central composite design (CCD) has also been employed for statistical modeling and analysis of the effects and interactions of significant variables dealing with the Cr(VI) uptake process by the developed sorbent. The predicted optimal conditions were situated at a pH of 5.5, contact time of 3.4 h, and 3.0 g L −1 dose. The Langmuir, Freundlich, and Temkin isotherm models were used to describe the equilibrium sorption of Cr(VI) by the absorbent, and the Langmuir isotherm showed the best concordance as an equilibrium model. The adsorption process was followed by a pseudo-second-order kinetic model. Thermodynamic investigations showed that the biosorption process was spontaneous and exothermic. - Highlights: • Fe3O4 nanoparticles were modified with Poly(methyl methacrylate) grafted Tragacanth gum • P(MMA)-g-TG -MNPs can preferentially adsorb Cr(VI) in the presence of Cr(III) • The effects of operational parameters on Cr(VI) removal were evaluated by RSM • Adsorption mechanism, kinetics, and isotherm have been explored • The sorbent was successfully used to remove Cr(VI) from different water samples

  14. Radiological visualization of prosthetic heart valves in situ

    International Nuclear Information System (INIS)

    Hoffmeister, H.M.; Pirschel, J.

    1986-01-01

    To determine the radiographic appearance of prosthetic heart valves 15 different models were investigated in situ. Fluoroscopy with detail radiographs and standard chest-radiographs were used for identification of the specific type of the prosthesis, for determination of details of the valve apparatus and for evaluation of the motion of the valve disc/ball. - Fluoroscopy and routine radiographs provided sufficient information to identify all prosthetic heart valves with exception of the Xenomedica bioprosthesis. If radiopaque material was used for the valve disc/ball, fluoroscopic assessment of the function of the valve was possible. Thus, in most types of disc or ball valves the opening/closing of the valve can be visualized, whereas in bioprosthesis a radiological determination of the mechanical function is not possible. (orig.) [de

  15. Customized mold radiotherapy with prosthetic apparatus for oral cancers

    International Nuclear Information System (INIS)

    Noguchi, Tadahide; Tsuchiya, Yoshiyuki; Hayasaka, Junichi; Itoh, Hiroto; Jinbu, Yoshinori; Kusama, Mikio; Takahashi, Satoru; Nakazawa, Masanori

    2014-01-01

    Eight patients (6 males, 2 females; median age, 78 years; age range, 31-94 years) were treated by mold radiotherapy with a prosthetic apparatus for oral cancers between October 2006 and March 2013. The primary sites were the tongue in 3 cases, hard palate and buccal mucosa in 2 cases each, and oral floor in 1 case. The type of treatment consisted of radical radiotherapy and palliative radiotherapy in 2 cases each, and preoperative radiotherapy, postoperative radiotherapy, additional radiotherapy after external beam radiotherapy and systemic chemotherapy in 1 case each. Patients received 40-50 Gy in 8-10 fractions with mold radiotherapy. Two patients who received radical radiotherapy showed no signs of recurrence or metastasis. The present therapy contributed to patients' palliative, postoperative, and preoperative therapy. Mold radiotherapy with a prosthetic appliance was performed safely and was a useful treatment for several types of oral cancer. (author)

  16. Self-cleaning skin-like prosthetic polymer surfaces

    Science.gov (United States)

    Simpson, John T [Clinton, TN; Ivanov, Ilia N [Knoxville, TN; Shibata, Jason [Manhattan Beach, CA

    2012-03-27

    An external covering and method of making an external covering for hiding the internal endoskeleton of a mechanical (e.g., prosthetic) device that exhibits skin-like qualities is provided. The external covering generally comprises an internal bulk layer in contact with the endoskeleton of the prosthetic device and an external skin layer disposed about the internal bulk layer. The external skin layer is comprised of a polymer composite with carbon nanotubes embedded therein. The outer surface of the skin layer has multiple cone-shaped projections that provide the external skin layer with superhydrophobicity. The carbon nanotubes are preferably vertically aligned between the inner surface and outer surface of the external skin layer in order to provide the skin layer with the ability to transmit heat. Superhydrophobic powders may optionally be used as part of the polymer composite or applied as a coating to the surface of the skin layer to enhance superhydrophobicity.

  17. Illusory movement perception improves motor control for prosthetic hands

    Science.gov (United States)

    Marasco, Paul D.; Hebert, Jacqueline S.; Sensinger, Jon W.; Shell, Courtney E.; Schofield, Jonathon S.; Thumser, Zachary C.; Nataraj, Raviraj; Beckler, Dylan T.; Dawson, Michael R.; Blustein, Dan H.; Gill, Satinder; Mensh, Brett D.; Granja-Vazquez, Rafael; Newcomb, Madeline D.; Carey, Jason P.; Orzell, Beth M.

    2018-01-01

    To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement’s progress. This largely non-conscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. Here we report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. PMID:29540617

  18. Can we close large prosthetic space with orthodontics?

    Science.gov (United States)

    Mesko, Mauro Elias; Skupien, Jovito Adiel; Valentini, Fernanda; Pereira-Cenci, Tatiana

    2013-01-01

    For years, the treatment for the replacement of a missing tooth was a fixed dental prosthesis. Currently, implants are indicated to replace missing teeth due to high clinical success and with the advantage of not performing preparations in the adjacent tooth. Another option for space closure is the use of orthodontics associated to miniscrews for anchorage allowing better control of the orthodontic biomechanics and especially making possible closure of larger prosthetic spaces. Thus, this article describes two cases with indications and discussion of the advantages and disadvantages of using orthodontics for prosthetic spaces closure. The cases herein presented show that it is possible to close an space when there are available teeth in the adjacent area. It can be concluded that when a malocclusion is present there will be a strong trend to indicate space closure by orthodontic movement as it preserves natural teeth and seems a more physiological approach.

  19. Pseudotumor of the Hip due to Fungal Prosthetic Joint Infection

    Directory of Open Access Journals (Sweden)

    Stefano Artiaco

    2013-01-01

    Full Text Available Pseudotumors associated with total hip arthroplasty have been associated with metal-on-metal and metal-on-polyethylene total hip arthroplasties due to a granulomatous foreign-body reaction to methyl methacrylate, polyethylene, or metal ion release, but they have not been related to prosthetic joint infections. In this paper, we report an unusual case of Candida albicans total hip arthroplasty infection, causing a large inflammatory pseudotumor of the hip joint. Fungal periprosthetic joint infections are a rare clinical entity and difficult to diagnose, and a pseudotumor may be part of their clinical presentation. They should be suspected in immunodeficient host patients when clinical symptoms of prosthetic joint infections are observed.

  20. Evaluation of a xenogeneic acellular collagen matrix as a small-diameter vascular graft in dogs--preliminary observations.

    Science.gov (United States)

    Nemcova, S; Noel, A A; Jost, C J; Gloviczki, P; Miller, V M; Brockbank, K G

    2001-01-01

    Autogenous veins are the materials of choice for arterial reconstruction. In the absence of autogenous material, prosthetic materials are used. However, vascular prostheses of less than 0.4 cm in diameter have low long-term patency. This study was designed to determine if cells would infiltrate an engineered xenogeneic biomaterial used as a small diameter arterial graft in dogs and, if so, to determine the phenotype of the infiltrating cells. Nine acellular xenogeneic grafts (0.4 cm in diameter, 5 cm long), composed of porcine collagen derived from the submucosa of the small intestine and type I bovine collagen, were implanted as end to-end interposition grafts in femoral arteries of five male mongrel dogs (total of nine grafts). All dogs received daily aspirin (325 mg). Patency of implanted grafts was monitored weekly by Duplex ultrasonography. After 9 weeks, or earlier in case of blood flow reduction by at least 75%, grafts were explanted and prepared for light or electron microscopy to evaluate cellularization. Eight of nine grafts remained patent up to 9 weeks. At explant, diameters were 0.31 +/- 0.02 cm at the midgraft, and 0.14 +/- 0.01 and 0.19 +/- 0.01 cm at the proximal and distal anastomoses. At explant, cells of mesenchymal origin (endothelial cells, smooth muscle cells, myofibroblasts) were embedded in the extracellular matrix of the graft scaffold. Minimal evidence of cellular inflammatory reaction and no aneurysmal dilatation or thrombus formation was detected. Variable degrees of hyperplasia were present at proximal and distal anastomoses. This preliminary study demonstrates that a collagen-based xenogeneic biomaterial provides a scaffold for cellularization when used for arterial reconstruction in dogs.

  1. Hydrophilic/hydrophobic character of grafted cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Takacs, E., E-mail: takacs@iki.kfki.h [Institute of Isotopes, Hungarian Academy of Sciences, Budapest (Hungary); Wojnarovits, L. [Institute of Isotopes, Hungarian Academy of Sciences, Budapest (Hungary); Borsa, J. [Budapest University of Technology and Economics (Hungary); Racz, I. [Bay Zoltan Institute for Materials Science and Technology, Budapest (Hungary)

    2010-04-15

    Vinyl monomers with long paraffin chains were grafted onto two kinds of cellulose (cotton and cotton linter) by direct irradiation grafting technique. The effect of dose, monomer structure and concentration, as well as homopolymer suppressor (styrene) concentration on the grafting yield was studied and the optimal grafting conditions were established. Grafting decreased the swelling of the samples in water and increased their polymer compatibility in polypropylene matrix.

  2. Computed tomography evaluation of autogenous graft in sinus lift surgery; Analise por tomografia computadorizada do enxerto autogeno na cirurgia de 'sinus lift'

    Energy Technology Data Exchange (ETDEWEB)

    Ajzen, Sergio Aron; Moscatiello, Rafael Andrade; Lima, Aida Maria Custodio de; Moscatiello, Vitoria Aparecida Muglia; Helio Kiitiro Yamashita [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Dept. de Diagnostico por Imagem; Mosacatiello, Rafael Muglia; Nishiguchi, Celso Itiro [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Tecnica Operatoria e Cirurgia Experimental; Alves, Maria Teresa de Seixas [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Disciplina de Anatomia Patologica

    2001-02-01

    The objective was to quantify bone formation within autogenous bone grafts and autogenous bone grafts in combination with platelet-rich plasma obtained either from apheresis or centrifugation using computed tomography. This prospective, double-blind study was conducted in 34 male and female adult patients (mean age of 28 years and 8 months), with either unilateral or bilateral pneumatization of the maxillary sinuses, requiring bone graft for dental implant. All patients were submitted to computed tomography examinations prior and six months after sinus lift surgery. Fifty-three maxillary sinuses were operated and divided into three distinct groups: autogenous bone graft, autogenous bone graft in combination with platelet-rich plasma obtained by centrifugation, and autogenous bone graft in combination with platelet-rich plasma obtained by apheresis. The results showed that computed tomography demonstrated bone growth in height and width between the initial and the follow-up computed tomography scans in all three groups. However, no statistical difference was found either for bone height or width. It was concluded that clinical evidence demonstrates the effectiveness of autogenous bone grafts, particularly when used in combination with bone growth factors such as platelet-rich plasma, which allow prosthetic and functional restoration of maxillofacial structures through fixation of dental implants. (author)

  3. Lactococcus garvieae Endocarditis on a Prosthetic Biological Aortic Valve.

    Science.gov (United States)

    Tsur, A; Slutzki, T; Flusser, D

    2015-09-01

    Lactococcus garvieae (LG) endocarditis is a rare disease in humans. There are only about 16 reported cases in the world. We report a 76-year-old male patient with LG endocarditis. In depth interview with the patient revealed that 2 weeks prior to admission, he had eaten sushi containing raw fish. Unlike many of the other infections reported, which were on a native mitral valve, our patient's vegetation was on a prosthetic aortic valve. © 2014 Blackwell Verlag GmbH.

  4. Neural-Network Control Of Prosthetic And Robotic Hands

    Science.gov (United States)

    Buckley, Theresa M.

    1991-01-01

    Electronic neural networks proposed for use in controlling robotic and prosthetic hands and exoskeletal or glovelike electromechanical devices aiding intact but nonfunctional hands. Specific to patient, who activates grasping motion by voice command, by mechanical switch, or by myoelectric impulse. Patient retains higher-level control, while lower-level control provided by neural network analogous to that of miniature brain. During training, patient teaches miniature brain to perform specialized, anthropomorphic movements unique to himself or herself.

  5. A novel polymeric prosthetic heart valve: design, manufacture, and testing

    OpenAIRE

    Brubert, Jacob

    2016-01-01

    In this thesis a flexible leaflet polymeric prosthetic aortic heart valve was designed, manufactured, and tested. The prosthesis was designed with the aim of overcoming the need for anticoagulant therapy, which is required for current mechanical prostheses; while also having lifelong durability, which current bioprosthetic heart valves are not able to achieve. Inspired by the anisotropic architecture of collagen in the natural valve, a shortlist of polystyrene based block copolymers (BCPs), w...

  6. Quality of life after maxillectomy and prosthetic obturator rehabilitation.

    Science.gov (United States)

    Chigurupati, Radhika; Aloor, Neelam; Salas, Richard; Schmidt, Brian L

    2013-08-01

    Surgical resection of midface neoplasms and subsequent reconstruction have been shown to have significant negative effects on quality of life (QOL). The purpose of this pilot study was to assess individuals' health-related QOL after maxillectomy and reconstruction with a prosthetic obturator. The QOL of 25 of 43 patients who underwent maxillectomy and prosthetic obturator reconstruction at the University of California-San Francisco was assessed using 3 questionnaires: University of Washington Quality of Life version 4 (UWQOL), Obturator Functioning Scale (OFS), and Mental Health Inventory (MHI). The response rate to the QOL questionnaires was 92% (23 of 25 patients). Time elapsed from maxillectomy and prosthetic obturator reconstruction to the QOL survey response ranged from 0.3 to 6.6 years (mean, 2.7 years; standard deviation [SD], 1.9 years). The post-treatment mean QOL scores were 77.3 (SD, 13.6) for UWQOL, 72.0 (SD, 12.6) for OFS, and 4.5 (SD, 0.9) for Mental Health Inventory. Individuals who received adjuvant radiation scored lower for speech and appearance (OFS, P = .05, P = .03, respectively) as well as for saliva and overall QOL (UWQOL, P = .02, P = .08, respectively). There was a strong correlation between QOL scores in OFS and UWQOL questionnaires (r = 0.78, P maxillectomy and prosthetic obturator reconstruction. There is further need for a multicenter trial with a larger sample to identify how factors affecting QOL of patients after maxillectomy might influence the choice of reconstruction. Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Prosthetic rehabilitation for a patient with microstomia: a case report

    Directory of Open Access Journals (Sweden)

    Moslehifard E

    2011-04-01

    Full Text Available "nFabrication of dental prosthesis for patients with microstomia has long been a problem for dentists. Microstomia is defined as an abnormally small oral orifice. Prosthetic rehabilitation of microstomia patients presents difficulties at all stages, from the preliminary impressions to fabrication of prosthesis. This study described a method for making impressions for patients with limited opening of the oral cavity which the use of a full-size impression tray was not possible.

  8. Simplified Prosthetic Rehabilitation of a Patient after Oral Cancer Removal

    OpenAIRE

    Nikola Džakula; Josip Kranjčić; Denis Vojvodić

    2016-01-01

    The treatment of patients with oral cancer is complex: a multidisciplinary approach needs to be taken and maxillofacial and oral surgeons, an oncologist, a prosthodontist should be included, and a psychologist is often needed. This case report describes the prosthetic rehabilitation of a patient after surgical removal of oral cancer with obturator prosthesis. Resection cavity was located in central part of the hard palate and the condition belonged to Aramany class 3 maxillary defects. The tw...

  9. Factors influencing the cost of prosthetic joint infection treatment.

    Science.gov (United States)

    Peel, T N; Cheng, A C; Lorenzo, Y P; Kong, D C M; Buising, K L; Choong, P F M

    2013-11-01

    Prosthetic joint infection (PJI) is associated with significant costs to the healthcare system. Current literature examines the cost of specific treatment modalities without assessing other cost drivers for PJI. To examine the overall cost of the treatment of PJI and to identify factors associated with management costs. The costs of treatment of prosthetic joint infections were examined in 139 patients across 10 hospitals over a 3-year period (January 2006 to December 2008). Cost calculations included hospitalization costs, surgical costs, hospital-in-the-home costs and antibiotic therapy costs. Negative binomial regression analysis was performed to model factors associated with total cost. The median cost of treating prosthetic joint infection per patient was Australian $34,800 (interquartile range: 20,305, 56,929). The following factors were associated with increased treatment costs: septic revision arthroplasty (67% increase in treatment cost; P = 0.02), hypotension at presentation (70% increase; P = 0.03), polymicrobial infections (41% increase; P = 0.009), surgical treatment with one-stage exchange (100% increase; P = 0.002) or resection arthroplasty (48% increase; P = 0.001) were independently associated with increased treatment costs. Culture-negative prosthetic joint infections were associated with decreased costs (29% decrease in treatment cost; P = 0.047). Treatment failure was associated with 156% increase in treatment costs. This study identifies clinically important factors influencing treatment costs that may be of relevance to policy-makers, particularly in the setting of hospital reimbursement and guiding future research into cost-effective preventive strategies. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  10. Structural Transitions of Solvent-Free Oligomer-Grafted Nanoparticles

    KAUST Repository

    Chremos, Alexandros

    2011-09-01

    Novel structural transitions of solvent-free oligomer-grafted nanoparticles are investigated by using molecular dynamics simulations of a coarse-grained bead-spring model. Variations in core size and grafting density lead to self-assembly of the nanoparticles into a variety of distinct structures. At the boundaries between different structures, the nanoparticle systems undergo thermoreversible transitions. This structural behavior, which has not been previously reported, deviates significantly from that of simple liquids. The reversible nature of these transitions in solvent-free conditions offers new ways to control self-assembly of nanoparticles at experimentally accessible conditions. © 2011 American Physical Society.

  11. Air Pump-Assisted Graft Centration, Graft Edge Unfolding, and Graft Uncreasing in Young Donor Graft Pre-Descemet Endothelial Keratoplasty.

    Science.gov (United States)

    Jacob, Soosan; Narasimhan, Smita; Agarwal, Amar; Agarwal, Athiya; A I, Saijimol

    2017-08-01

    To assess an air pump-assisted technique for graft centration, graft edge unfolding, and graft uncreasing while performing pre-Descemet endothelial keratoplasty (PDEK) using young donor grafts. Continuous pressurized air infusion was used for graft centration, graft edge unfolding, and graft unwrinkling. Ten eyes of 10 patients underwent PDEK with donors aged below 40 years. In all eyes, the donor scrolled into tight scrolls. In all cases, the air pump-assisted technique was effective in positioning and centering the graft accurately and in straightening infolded graft edges and smoothing out graft creases and wrinkles. Endothelial cell loss was 38.6%. Postoperative best-corrected visual acuity at 6 months was 0.66 ± 0.25 in decimal equivalent. Continuous pressurized air infusion acted as a third hand providing a continuous pressure head that supported the graft and prevented graft dislocation as well as anterior chamber collapse during intraocular maneuvering. Adequate maneuvering space was available in all cases, and bleeding, if any, was tamponaded successfully in all cases. Although very young donor grafts may be used for PDEK, they are difficult to center and unroll completely before floating against host stroma. An air pump-assisted technique using continuous pressurized air infusion allows successful final graft positioning even with very young donor corneas. It thus makes surgery easier as several key steps are made easier to handle. It additionally helps in tamponading hemorrhage during peripheral iridectomy, increasing surgical space, preventing fluctuations in the anterior chamber depth, and promoting graft adherence.

  12. Vascular complications of prosthetic inter-vertebral discs.

    Science.gov (United States)

    Daly, Kevin J; Ross, E Raymond S; Norris, Heather; McCollum, Charles N

    2006-10-01

    Five consecutive cases of prosthetic inter-vertebral disc displacement with severe vascular complications on revisional surgery are described. The objective of this case report is to warn spinal surgeons that major vascular complications are likely with anterior displacement of inter-vertebral discs. We have not been able to find a previous report on vascular complications associated with anterior displacement of prosthetic inter-vertebral discs. In all five patients the prosthetic disc had eroded into the bifurcation of the inferior vena cava and the left common iliac vein. In three cases the aortic bifurcation was also involved. The fibrosis was so severe that dissecting out the arteries and veins to provide access to the relevant disc proved impossible. Formal division of the left common iliac vein and artery with subsequent repair was our solution. Anterior inter-vertebral disc displacement was associated with severe vascular injury. Preventing anterior disc displacement is essential in disc design. In the event of anterior displacement, disc removal should be planned with a Vascular Surgeon.

  13. Iodine-125 orbital brachytherapy with a prosthetic implant in situ

    Energy Technology Data Exchange (ETDEWEB)

    Stannard, Clare [Groote Schuur Hospital and Cape Town Univ. (South Africa). Dept. of Radiation Oncology; Maree, Gert; Munro, Roger [Groote Schuur Hospital and Cape Town Univ. (South Africa). Dept. of Medical Physics; Lecuona, Karin [Groote Schuur Hospital and Cape Town Univ. (South Africa). Dept. of Ophthalmology; Sauerwein, Wolfgang [Universitaetsklinikum Essen (Germany). Strahlenklinik, NCTeam

    2011-05-15

    Purpose: Brachytherapy is one method of irradiating the orbit after enucleation of an eye with a malignant tumor that has a potential to recur. It consists of 6 trains of I-125 seeds placed around the periphery of the orbit, a shorter central train, and a metal disc, loaded with seeds, placed beneath the eyelids. The presence of a prosthetic orbital implant requires omission of the central train and adjustment of the activity of the seeds in the anterior orbit around the prosthesis. Patients and Methods: This is a retrospective review of the technical modifications and outcome of 12 patients treated in this manner: 6 with retinoblastoma, 5 with malignant melanoma, and 1 with an intraocular rhabdomyosarcoma. The median dose was 35.5 Gy in 73 hours for retinoblastoma and 56 Gy in 141 hours for malignant melanoma. Patients with retinoblastoma and rhabdomyosarcoma also received chemotherapy. Results: The tubes can be placed satisfactorily around the prosthesis. The increased activity in the anterior half of the tubes produced comparable dose distributions. There have been no orbital recurrences, no extrusion of the prosthesis, and cosmesis is good. Conclusion: Insertion of a prosthetic implant at the time of enucleation greatly enhances the subsequent cosmetic appearance. This should be encouraged unless there is frank tumor in the orbit. Orbital brachytherapy without the central train continues to give excellent local control. The short treatment time and good cosmesis are added advantages. The patient is spared the expense and inconvenience of removing and replacing the prosthetic implant. (orig.)

  14. Overview: Mechanism and Control of a Prosthetic Arm.

    Science.gov (United States)

    Kulkarni, Tushar; Uddanwadiker, Rashmi

    2015-09-01

    Continuous growth in industrialization and lack of awareness in safety parameters the cases of amputations are growing. The search of safer, simpler and automated prosthetic arms for managing upper limbs is expected. Continuous efforts have been made to design and develop prosthetic arms ranging from simple harness actuated to automated mechanisms with various control options. However due the cost constraints, the automated prosthetic arms are still out of the reach of needy people. Recent data have shown that there is a wide scope to develop a low cost and light weight upper limb prosthesis. This review summarizes the various designs methodologies, mechanisms and control system developed by the researchers and the advances therein. Educating the patient to develop acceptability to prosthesis and using the same for the most basic desired functions of human hand, post amputation care and to improve patient's independent life is equally important. In conclusion it can be interpreted that there is a wide scope in design in an adaptive mechanism for opening and closing of the fingers using other methods of path and position synthesis. Simple mechanisms and less parts may optimize the cost factor. Reduction in the weight of the prosthesis may be achieved using polymers used for engineering applications. Control system will remain never ending challenge for the researchers, but it is essential to maintain the simplicity from the patients perspective.

  15. [Virtual Planning of Prosthetic Treatment of the Orbit].

    Science.gov (United States)

    Veit, Johannes A; Thierauf, Julia; Egner, Kornelius; Wiggenhauser, Paul Severin; Friedrich, Daniel; Greve, Jens; Schuler, Patrick J; Hoffmann, Thomas K; Schramm, Alexander

    2017-06-01

    Optimal positioning of bone-anchored implants in the treatment of patients with orbital prosthesis is challenging. The definition of implant axis as well as the positioning of the implants is important to prevent failures in prosthetic rehabilitation in these patients. We performed virtual planning of enossal implants at a base of a standard fan beam CT scan using the software CoDiagnostiX™ (DentalWings, Montréal, Canada). By 3D-printing a surgical guide for drilling and implant insertion was manufactured (Med-610™, Stratasys, Rehovot, Israel). An orbital exenteration was performed in a patient after shrinkage of the eyelids 20 years after enucleation and radiation of the orbit due to rhabdomyosarcoma. 4 Vistafix-3 implants (Cochlear™, Cochlea, Centennial, USA) were primarily inserted after resection with the help of the 3D-surgical guide. Prosthetic rehabilitation could be achieved as preplanned to a predictable result. The individual prosthesis of the orbit showed good functional and esthetic outcome. The virtual 3D-planning of endosseous implants for prosthetic orbital and periorbital reconstruction is easy to use and facilitates optimal placement of implants especially in posttherapeutically altered anatomic situations. © Georg Thieme Verlag KG Stuttgart · New York.

  16. A smartphone photogrammetry method for digitizing prosthetic socket interiors.

    Science.gov (United States)

    Hernandez, Amaia; Lemaire, Edward

    2017-04-01

    Prosthetic CAD/CAM systems require accurate 3D limb models; however, difficulties arise when working from the person's socket since current 3D scanners have difficulties scanning socket interiors. While dedicated scanners exist, they are expensive and the cost may be prohibitive for a limited number of scans per year. A low-cost and accessible photogrammetry method for socket interior digitization is proposed, using a smartphone camera and cloud-based photogrammetry services. 15 two-dimensional images of the socket's interior are captured using a smartphone camera. A 3D model is generated using cloud-based software. Linear measurements were comparing between sockets and the related 3D models. 3D reconstruction accuracy averaged 2.6 ± 2.0 mm and 0.086 ± 0.078 L, which was less accurate than models obtained by high quality 3D scanners. However, this method would provide a viable 3D digital socket reproduction that is accessible and low-cost, after processing in prosthetic CAD software. Clinical relevance The described method provides a low-cost and accessible means to digitize a socket interior for use in prosthetic CAD/CAM systems, employing a smartphone camera and cloud-based photogrammetry software.

  17. Novel implant for peri-prosthetic proximal tibia fractures.

    Science.gov (United States)

    Tran, Ton; Chen, Bernard K; Wu, Xinhua; Pun, Chung Lun

    2018-03-01

    Repair of peri-prosthetic proximal tibia fractures is very challenging in patients with a total knee replacement or arthroplasty. The tibial component of the knee implant severely restricts the fixation points of the tibial implant to repair peri-prosthetic fractures. A novel implant has been designed with an extended flange over the anterior of tibial condyle to provide additional points of fixation, overcoming limitations of existing generic locking plates used for proximal tibia fractures. Furthermore, the screws fixed through the extended flange provide additional support to prevent the problem of subsidence of tibial component of knee implant. The design methodology involved extraction of bone data from CT scans into a flexible CAD format, implant design and structural evaluation and optimisation using FEM as well as prototype development and manufacture by selective laser melting 3D printing technology with Ti6Al4 V powder. A prototype tibia implant was developed based on a patient-specific bone structure, which was regenerated from the CT images of patient's tibia. The design is described in detail and being applied to fit up to 80% of patients, for both left and right sides based on the average dimensions and shape of the bone structure from a wide range of CT images. A novel tibial implant has been developed to repair peri-prosthetic proximal tibia fractures which overcomes significant constraints from the tibial component of existing knee implant. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Prosthetic design directives: Low-cost hands within reach.

    Science.gov (United States)

    Jones, G K; Rosendo, A; Stopforth, R

    2017-07-01

    Although three million people around the world suffer from the lack of one or both upper limbs 80% of this number is located within developing countries. While prosthetic prices soar with technology 3D printing and low cost electronics present a sensible solution for those that cannot afford expensive prosthetics. The electronic and control design of a low-cost prosthetic hand, the Touch Hand II, is discussed. This paper shows that sensorless techniques can be used to reduce design complexities, costs, and provide easier access to the electronics. A closing and opening finite state machine (COFSM) was developed to handle the actuated digit joint control state and a supervisory switching control scheme, used for speed and grip strength control. Three torque and speed settings were created to be preset for specific grasps. The hand was able to replicate ten frequently used grasps and grip some common objects. Future work is necessary to enable a user to control it with myoelectric signals (MESs) and to solve operational problems related to electromagnetic interference (EMI).

  19. Ergonomic workplace assessment in orthotic and prosthetic workshops.

    Science.gov (United States)

    Salmani Nodooshan, H; Koohi Booshehri, S; Daneshmandi, H; Choobineh, A R

    2016-10-17

    In Iranian orthotic and prosthetic workshops, the majority of activities are carried out by manpower and the tasks are labor-intensive. In these workshops, ergonomic aspects of working conditions are seldom considered. This study was conducted in orthotic and prosthetic workshops with the objectives of determination of prevalence rate of MSDs among employees and assessment of ergonomics working conditions. In this cross-sectional study, all employees (n = 42; 29 males and 13 females) in 11 active orthotic and prosthetic production centers of Shiraz city participated. Data were collected using Nordic Musculoskeletal disorders Questionnaire (NMQ) and observational technique by an ergonomics checklist for assessment of working conditions. The means (SD) of age and job tenure (years) in the study individuals were 37.26 (10.21) and 12.8 (9.39), respectively. The most prevalent MSD symptoms in the past 12 months were reported in the lower back (42.9%), shoulders (40.5%) and knees (40.5%). Working conditions assessment showed that the main ergonomic problems in the workshops studied originated from awkward working posture, improper workstation design, poorly designed hand tools and incorrect manual material handling. Any interventional program for working conditions improvement should, therefore, focus on these areas.

  20. Prosthetic Leg Control in the Nullspace of Human Interaction.

    Science.gov (United States)

    Gregg, Robert D; Martin, Anne E

    2016-07-01

    Recent work has extended the control method of virtual constraints, originally developed for autonomous walking robots, to powered prosthetic legs for lower-limb amputees. Virtual constraints define desired joint patterns as functions of a mechanical phasing variable, which are typically enforced by torque control laws that linearize the output dynamics associated with the virtual constraints. However, the output dynamics of a powered prosthetic leg generally depend on the human interaction forces, which must be measured and canceled by the feedback linearizing control law. This feedback requires expensive multi-axis load cells, and actively canceling the interaction forces may minimize the human's influence over the prosthesis. To address these limitations, this paper proposes a method for projecting virtual constraints into the nullspace of the human interaction terms in the output dynamics. The projected virtual constraints naturally render the output dynamics invariant with respect to the human interaction forces, which instead enter into the internal dynamics of the partially linearized prosthetic system. This method is illustrated with simulations of a transfemoral amputee model walking with a powered knee-ankle prosthesis that is controlled via virtual constraints with and without the proposed projection.

  1. Nuclear Medicine in Diagnosis of Prosthetic Valve Endocarditis: An Update

    Science.gov (United States)

    Musso, Maria; Petrosillo, Nicola

    2015-01-01

    Over the past decades cardiovascular disease management has been substantially improved by the increasing introduction of medical devices as prosthetic valves. The yearly rate of infective endocarditis (IE) in patient with a prosthetic valve is approximately 3 cases per 1,000 patients. The fatality rate of prosthetic valve endocarditis (PVE) remains stable over the years, in part due to the aging of the population. The diagnostic value of echocardiography in diagnosis is operator-dependent and its sensitivity can decrease in presence of intracardiac devices and valvular prosthesis. The modified Duke criteria are considered the gold standard for diagnosing IE; their sensibility is 80%, but in clinical practice their diagnostic accuracy in PVE is lower, resulting inconclusively in nearly 30% of cases. In the last years, these new imaging modalities have gained an increasing attention because they make it possible to diagnose an IE earlier than the structural alterations occurring. Several studies have been conducted in order to assess the diagnostic accuracy of various nuclear medicine techniques in diagnosis of PVE. We performed a review of the literature to assess the available evidence on the role of nuclear medicine techniques in the diagnosis of PVE. PMID:25695043

  2. Smartphones as image processing systems for prosthetic vision.

    Science.gov (United States)

    Zapf, Marc P; Matteucci, Paul B; Lovell, Nigel H; Suaning, Gregg J

    2013-01-01

    The feasibility of implants for prosthetic vision has been demonstrated by research and commercial organizations. In most devices, an essential forerunner to the internal stimulation circuit is an external electronics solution for capturing, processing and relaying image information as well as extracting useful features from the scene surrounding the patient. The capabilities and multitude of image processing algorithms that can be performed by the device in real-time plays a major part in the final quality of the prosthetic vision. It is therefore optimal to use powerful hardware yet to avoid bulky, straining solutions. Recent publications have reported of portable single-board computers fast enough for computationally intensive image processing. Following the rapid evolution of commercial, ultra-portable ARM (Advanced RISC machine) mobile devices, the authors investigated the feasibility of modern smartphones running complex face detection as external processing devices for vision implants. The role of dedicated graphics processors in speeding up computation was evaluated while performing a demanding noise reduction algorithm (image denoising). The time required for face detection was found to decrease by 95% from 2.5 year old to recent devices. In denoising, graphics acceleration played a major role, speeding up denoising by a factor of 18. These results demonstrate that the technology has matured sufficiently to be considered as a valid external electronics platform for visual prosthetic research.

  3. ARM-based visual processing system for prosthetic vision.

    Science.gov (United States)

    Matteucci, Paul B; Byrnes-Preston, Philip; Chen, Spencer C; Lovell, Nigel H; Suaning, Gregg J

    2011-01-01

    A growing number of prosthetic devices have been shown to provide visual perception to the profoundly blind through electrical neural stimulation. These first-generation devices offer promising outcomes to those affected by degenerative disorders such as retinitis pigmentosa. Although prosthetic approaches vary in their placement of the stimulating array (visual cortex, optic-nerve, epi-retinal surface, sub-retinal surface, supra-choroidal space, etc.), most of the solutions incorporate an externally-worn device to acquire and process video to provide the implant with instructions on how to deliver electrical stimulation to the patient, in order to elicit phosphenized vision. With the significant increase in availability and performance of low power-consumption smart phone and personal device processors, the authors investigated the use of a commercially available ARM (Advanced RISC Machine) device as an externally-worn processing unit for a prosthetic neural stimulator for the retina. A 400 MHz Samsung S3C2440A ARM920T single-board computer was programmed to extract 98 values from a 1.3 Megapixel OV9650 CMOS camera using impulse, regional averaging and Gaussian sampling algorithms. Power consumption and speed of video processing were compared to results obtained to similar reported devices. The results show that by using code optimization, the system is capable of driving a 98 channel implantable device for the restoration of visual percepts to the blind.

  4. FAS grafted superhydrophobic ceramic membrane

    Energy Technology Data Exchange (ETDEWEB)

    Lu Jun [School of Material Science and Engineering, Jingdezhen Ceramic Institute, 333001 Jingdezhen (China); Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, CAS, 1295 DingXi Road, Shanghai 200050 (China); Yu Yun, E-mail: yunyush@mail.sic.ac.cn [Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, CAS, 1295 DingXi Road, Shanghai 200050 (China); Zhou Jianer [School of Material Science and Engineering, Jingdezhen Ceramic Institute, 333001 Jingdezhen (China); Song Lixin; Hu Xingfang [Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, CAS, 1295 DingXi Road, Shanghai 200050 (China); Larbot, Andre [Institut Europeen des Membranes, UMR 5635-CNRS, ENSCM, UMII, 1919 Route de Mende 34293, Montpellier Cedex 5 (France)

    2009-08-30

    The hydrophobic properties of {gamma}-Al{sub 2}O{sub 3} membrane have been obtained by grafting fluoroalkylsilane (FAS) on the surface of the membrane. The following grafting parameters were studied: the eroding time of the original membrane, the grafting time, the concentration of FAS solution and the multiplicity of grafting. Hydrophobicity of the membranes was characterized by contact angle (CA) measurement. The thermogravimetric analysis (TGA) was used to investigate the weight loss process (25-800 deg. C) of the fluoroalkylsilane grafted on Al{sub 2}O{sub 3} powders under different grafting conditions. The morphologies of the membranes modified under different parameters were examined by field emission scanning electron microscopy (FE-SEM) and the surface roughness (Ra) was measured using white light interferometers. A needle-like structure was observed on the membrane surface after modification, which causes the change of Ra. On the results above, we speculated a model to describe the reaction between FAS and {gamma}-Al{sub 2}O{sub 3} membrane surface as well as the formed surface morphology.

  5. FAS grafted superhydrophobic ceramic membrane

    Science.gov (United States)

    Lu, Jun; Yu, Yun; Zhou, Jianer; Song, Lixin; Hu, Xingfang; Larbot, Andre

    2009-08-01

    The hydrophobic properties of γ-Al 2O 3 membrane have been obtained by grafting fluoroalkylsilane (FAS) on the surface of the membrane. The following grafting parameters were studied: the eroding time of the original membrane, the grafting time, the concentration of FAS solution and the multiplicity of grafting. Hydrophobicity of the membranes was characterized by contact angle (CA) measurement. The thermogravimetric analysis (TGA) was used to investigate the weight loss process (25-800 °C) of the fluoroalkylsilane grafted on Al 2O 3 powders under different grafting conditions. The morphologies of the membranes modified under different parameters were examined by field emission scanning electron microscopy (FE-SEM) and the surface roughness (Ra) was measured using white light interferometers. A needle-like structure was observed on the membrane surface after modification, which causes the change of Ra. On the results above, we speculated a model to describe the reaction between FAS and γ-Al 2O 3 membrane surface as well as the formed surface morphology.

  6. Interventions in Infrainguinal Bypass Grafts

    International Nuclear Information System (INIS)

    Mueller-Huelsbeck, S.; Order, B.-M.; Jahnke, T.

    2006-01-01

    The interventional radiologist plays an important role in the detection and prevention of infrainguinal bypass failure. Early detection and evaluation of flow-limiting lesions effectively preserve graft (venous bypass and polyester or expanded polytetrafluoroethylene bypass) patency by identifying stenoses before occlusion occurs. Delay in treatment of the at-risk graft may result in graft failure and a reduced chance of successful revascularization. For this reason, surveillance protocols form an important part of follow-up after infrainguinal bypass surgery. As well as having an understanding of the application of imaging techniques including ultrasound, MR angiography, CT angiography and digital subtraction angiography, the interventional radiologist should have detailed knowledge of the minimally invasive therapeutic options. Percutaneous transluminal angioplasty (PTA), or alternatively cutting balloon angioplasty, is the interventional treatment of choice in prevention of graft failure and occlusion. Further alternatives include metallic stent placement, fibrinolysis, and mechanical thrombectomy. Primary assisted patency rates following PTA can be up to 65% at 5 years. When the endovascular approach is unsuccessful, these therapeutic options are complemented by surgical procedures including vein patch revision, jump grafting, or placement of a new graft

  7. Development of EPDM based thermoplastic elastomers for oil resistant applications: optimization of radiation grafting parameters

    International Nuclear Information System (INIS)

    Chaudhari, C.V.; Dubey, K.A.; Bhardwaj, Y.K.; Sabharwal, S.

    2008-01-01

    Full text: Ethylene-propylene diene terpolymer (EPDM) is currently among the most industrially useful elastomers because of its certain unique properties like excellent heat resistance, resistance towards ozone deterioration, high impact strength. However EPDM has a serious drawback of weak adhesion properties and tendency to swell in contact with paraffin oil and aromatic hydrocarbons. Blending EPDM with suitable polar elastomers or grafting polar polymer chains onto EPDM is an easy method to overcome this drawback. Radiation grafting of Acrylonitrile (ACN) on EPDM provides an easy and effective method of incorporating ACN uniformly on the EPDM backbone. Grafting of ACN on EPDM is expected to result grafted copolymer with better oil resistance, hardness and better compatibility with polar polymer matrices. In the present study radiation induced grafting of ACN onto EPDM rubber film was investigated by mutual radiation grafting technique. Effect of experimental variables viz. radiation dose, dose rate, types of solvents and monomer content on extent of grafting was studied. The solvent composition of Acetone:CCl 4 (20:80) was found to be the optimum mixture which resulted in highest degree of grafting. It was found that the degree of grafting increases with radiation dose, monomer content and decreases with dose rate

  8. Improvement of grafting procedures for the ornmental species: I. Picea pungens Engelm. var. glauca Regel

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2011-11-01

    Full Text Available In order to get ornamental trees for landscaping, Colorado blue spuce (Picea pungens Engelm. var. glauca Regel scions were grafted on Norway spruce (Picea abies (L. Karst. rootstocks.An original double-side-veneer grafting method was applied in five experimental or basic variants. The plastic tapes and the ecological Ceraltin® wax developed by the Research and Development of Bio-stimulators (CCDB BIOS Cluj were tested. In addition, two controls in which the classic raffia and the traditional hot wax and the classic side-veneer-grafting method were used. The obtained results, expressed in percents, were transformed in arcsin square root of percent values, and then a two-way analysis of variance (ANOVA was used. Highly significant (p < 0.001 statistical differences were found between all grafting variants, including controls. The Duncan test proved that original double-side-veneer grafting method and the new developed materials, i.e. plastic tapes and the ecological Ceraltin® wax have contributed in getting a better grafting success compared to the controls.Thus, the double-side-veneer grafting method and the two grafting materials are highly recommended to be used in getting grafted Colorado blue spuce ornamental trees.

  9. Improvement of grafting procedures for the ornamental species: I. Picea pungens Engelm. var. glauca Regel

    Directory of Open Access Journals (Sweden)

    Ioan Blada

    2013-12-01

    Full Text Available In order to get ornamental trees for landscaping, Colorado blue spuce (Picea pungens Engelm. var.glauca Regel scions were grafted on Norway spruce (Picea abies (L. Karst. rootstocks. An original double-side-veneer grafting method was applied in five experimental or basic variants. The plastic tapes and the ecological Ceraltin wax developed by the Research and Development of Bio-stimulators (CCDB BIOS Cluj were tested. In addition, two controls in which the classic raffia and the traditional hot wax and the classic side-veneer-grafting method were used. The obtained results, expressed in percents, were transformed in arcsin square root of percent values, and then a two-way analysis of variance (ANOVA was used. Highly significant (p < 0.001 statistical differences were found between all grafting variants, including controls. The Duncan test proved that original double-side-veneer grafting method and the new developed materials, i.e. plastic tapes and the ecological Ceraltin wax have contributed in getting a better grafting success compared to the controls.Thus, the double-side-veneer grafting method and the two grafting materials are highly recommended to be used in getting grafted Colorado blue spuce ornamental trees.

  10. Comparison of the efficiency, side effects and complications of the synthetic dural grafts: Beriplast and Tissudura

    OpenAIRE

    HAMZAOĞLU, Vural; ÖZALP, Hakan; KARKUCAK, Ahmet; ÇOKLUK, Cengiz

    2015-01-01

    The purpose of this study was to compare human fibrinogen-thrombin-based liquid dural graft; Beriplast® (Behring, Malburg, Germany) and collagen-based dural graft; Tissudura® (Baxter, Heidelberg, Germany) in terms of efficiency, side effects and complications. Thirty Spraque Dawley rats were used in this experimental study. A burrhole was opened on the left parietal bone of each subject and experimental dural defect was created. While 10 subjects were in sham group without any dural defect re...

  11. Surface Modifications of Polymers Induced by Heavy Ions Grafting

    Energy Technology Data Exchange (ETDEWEB)

    Mazzei, R O; Lombardo, J; Camporotondi, D; Tadey, D; Bermudez, G G [National Atomic Energy Commission, Ezeiza Atomic Centre, Ezeiza (Argentina)

    2012-09-15

    Polymer surfaces are modified by the application of swift heavy ions etching and grafting procedures. The residual active sites produced by heavy ion beams, remaining after the etching process, were used to start the grafting process. In order to produce tracks on foils of poly(vinylidene fluoride) (PVDF) they were irradiated with {sup 208}Pb of 25.62 MeV/n or with 115 MeV Cl ions. Moreover, foils of polypropylene (PP) were irradiated with {sup 208}Pb of 25.62 MeV/n. Then, they were etched and grafted with N-isopropylacrylamide (NIPAAm) monomers or with acrylic acid (AAc) monomers, respectively. The replica method allowed the observation of the shape of the grafted tracks using transmission electron microscopy (TEM). In addition NIPAAm grafted foils were analyzed using Fourier transform infrared spectroscopy (FTIR). The sulfonation procedure (methodology previously described for perfluorated polymers) was applied on grafted PVDF. A new method is described to produce a thin layer of poly-acrylic-acid (membranes) that grows on the surface of PVDF foils implanted by an Ar{sup +} beam with energies between 30-150 keV. Different combinations of monomers in water solutions were used such as: acrylic acid (AAc); acrylic acid-glycidyl methacrylate (AAc-GMA); acrylic acid-styrene (AAc-S); acrylic acid-N-isopropyl acrylamide (AAc-NIPAAm) and acrylic acid-N-isopropyl acrylamide - glycidyl methacrylate (AAc-NIPAAm-GMA). The experimental results show that for particular values of: ion fluence and energy, AAc concentration, sulphuric acid and PVDF polymorphous (alpha or beta) a huge percentage of grafting was obtained. At certain point of the grafting process the development of the PolyAAc-Xmonomer produce a detachment from the irradiated substrate and continue its grafting outside it. This method produces a membrane that is an increased replica of the original implanted surface. Finally, PVDF films implanted by an Ar{sup +} beam with energies about 100 keV and a fluence of 10

  12. Internal Prosthetic Replacement of Skeletal Segments Lost in Combat Injuries.

    Science.gov (United States)

    1973-08-31

    osteo- articular bone grafts. Clin. Ortho., 87: 156, 1972. 8. Tuli, S. M.: Bridging of bone defects by massive bone grafts in tumorous conditions. Clin...fashion in its proximal one-third to "prevent distractic ,n of the fragments. The fiber metal segment was then placed in the appropriate defect and the...defect slightly oversized and also osteotomizing the fibula to delete any possible distracting forces or angulating forces. The only complication in

  13. Non- invasive in vivo analysis of a murine aortic graft using high resolution ultrasound microimaging

    International Nuclear Information System (INIS)

    Rowinska, Zuzanna; Zander, Simone; Zernecke, Alma; Jacobs, Michael; Langer, Stephan; Weber, Christian; Merx, Marc W.; Koeppel, Thomas A.

    2012-01-01

    Introduction: As yet, murine aortic grafts have merely been monitored histopathologically. The aim of our study was to examine how these grafts can be monitored in vivo and non-invasively by using high-resolution ultrasound microimaging to evaluate function and morphology. A further aim was to prove if this in vivo monitoring can be correlated to immunohistological data that indicates graft integrity. Methods: Murine infrarenal aortic isografts were orthotopically transplanted into 14 female mice (C57BL/6-Background) whereas a group of sham-operated animals (n = 10) served as controls. To assess the graft morphology and hemodynamics, we examined the mice over a post-operative period of 8 weeks with a sophisticated ultrasound system (Vevo 770, Visual Sonics). Results: The non-invasive graft monitoring was feasible in all transplanted mice. We could demonstrate a regular post-transplant graft function and morphology, such as anterior/posterior wall displacement and wall thickness. Mild alterations of anterior wall motion dynamics could only be observed at the site of distal graft anastomosis (8 weeks after grafting (transplant vs. sham mice: 0.02 mm ± 0.01 vs. 0.03 mm ± 0.01, p < 0.05). However, the integrity of the entire graft wall could be confirmed by histopathological evaluation of the grafts. Conclusions: With regard to graft patency, function and morphology, high resolution ultrasound microimaging has proven to be a valuable tool for longitudinal, non-invasive, in vivo graft monitoring in this murine aortic transplantation model. Consequently, this experimental animal model provides an excellent basis for molecular and pharmacological studies using genetically engineered mice.

  14. Histological fate of abdominal dermis-fat grafts implanted in the temporomandibular joint of the rabbit following condylectomy.

    Science.gov (United States)

    Dimitroulis, G; Slavin, J; Morrison, W

    2011-02-01

    The histological fate of abdominal dermis-fat grafts implanted into the temporomandibular joint (TMJ) following condylectomy was studied. 21 rabbits underwent left TMJ discectomies and condylectomies; 6 were controls (Group A; no graft used); 15 (Group B) had autogenous abdominal grafts transplanted into the left TMJ. Animals were killed after 4, 12 and 20 weeks. Specimens of the TMJ were histologically and histomorphometrically evaluated. At 4 weeks, fat necrosis was clear in all specimens. The dermis component survived and formed cysts with no necrosis. By 12 weeks, viable fat deposits appeared with no evidence of necrotic fat. At 20 weeks, large amounts of viable fat were present in Group B specimens. Group A had no fat, although the missing condyles regenerated. In the presence of viable fat, Group B showed little condyle regeneration 20 weeks after condylectomy. Non-vascularised fat grafts do not survive transplantation, but stimulate neoadipogenesis. The fate of the dermis component of the graft is independent of the fat component. Fat in the joint space disrupts the regeneration of a new condylar head. Neoadipogensis inhibits growth of new bone and cartilage. This has clinical implications for TMJ ankylosis management and preventing heterotopic bone formation around prosthetic joints. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  15. A Prosthetic Foot Emulator to Optimize Prescription of Prosthetic Feet in Veterans and Service Members with Leg Amputations

    Science.gov (United States)

    2017-09-01

    mobility, prosthetic foot preference and walking ability after two weeks of use in the home and community setting. No exclusions based on sex , race...2012 Page 17 of 33 Data collection Photos and video recording With the participant’s explicit consent, we may take video and photos during portions of...this study, for documentation and use in research publications. All videos and photos will exclue the participant’s face and identifying marks will

  16. Radiation grafting on natural films

    International Nuclear Information System (INIS)

    Lacroix, M.; Khan, R.; Senna, M.; Sharmin, N.; Salmieri, S.; Safrany, A.

    2014-01-01

    Different methods of polymer grafting using gamma irradiation are reported in the present study for the preparation of newly functionalized biodegradable films, and some important properties related to their mechanical and barrier properties are described. Biodegradable films composed of zein and poly(vinyl alcohol) (PVA) were gamma-irradiated in presence of different ratios of acrylic acid (AAc) monomer for compatibilization purpose. Resulting grafted films (zein/PVA-g-AAc) had their puncture strength (PS=37–40 N mm −1 ) and puncture deformation (PD=6.5–9.8 mm) improved for 30% and 50% PVA in blend, with 5% AAc under 20 kGy. Methylcellulose (MC)-based films were irradiated in the presence of 2-hydroxyethyl methacrylate (HEMA) or silane, in order to determine the effect of monomer grafting on the mechanical properties of films. It was found that grafted films (MC-g-HEMA and MC-g-silane) using 35% monomer performed higher mechanical properties with PS values of 282–296 N mm −1 and PD of 5.0–5.5 mm under 10 kGy. Compatibilized polycaprolactone (PCL)/chitosan composites were developed via grafting silane in chitosan films. Resulting trilayer grafted composite film (PCL/chitosan-g-silane/PCL) presented superior tensile strength (TS=22 MPa) via possible improvement of interfacial adhesion (PCL/chitosan) when using 25% silane under 10 kGy. Finally, MC-based films containing crystalline nanocellulose (CNC) as a filling agent were prepared and irradiated in presence of trimethylolpropane trimethacrylate (TMPTMA) as a grafted plasticizer. Grafted films (MC-g-TMPTMA) presented superior mechanical properties with a TS of 47.9 MPa and a tensile modulus (TM) of 1792 MPa, possibly due to high yield formation of radicals to promote TMPTMA grafting during irradiation. The addition of CNC led to an additional improvement of the barrier properties, with a significant 25% reduction of water vapor permeability (WVP) of grafted films. - Highlights: • Irradiation of zein

  17. A survey of prosthetic eye wearers to investigate mucoid discharge

    Directory of Open Access Journals (Sweden)

    Pine K

    2012-05-01

    Full Text Available Keith Pine1, Brian Sloan2, Joanna Stewart3, Robert J Jacobs11Department of Optometry and Vision Science, 2Department of Ophthalmology, New Zealand National Eye Centre, 3Section of Epidemiology and Biostatistics, School of Population Health, University of Auckland, Auckland, New ZealandBackground: This study aimed to better understand the causes and treatments of mucoid discharge associated with prosthetic eye wear by reviewing the literature and surveying anophthalmic patients.Methods: An anonymous questionnaire was completed by 429 prosthetic eye wearers who used visual analog scales to self-measure their discharge experience for four discharge characteristics: frequency, color, volume, and viscosity. These characteristics were analyzed with age, ethnicity, years wearing a prosthesis, eye loss cause, removal and cleaning regimes, hand-washing behavior, age of current prosthesis, and professional repolishing regimes as explanatory variables. Eighteen ocularists’ Web sites containing comments on the cause and treatment of discharge were surveyed.Results: Associations were found between discharge frequency and cleaning regimes with more frequent cleaning accompanying more frequent discharge. Color was associated with years of wearing and age, with more years of wearing and older people having less colored discharge. Volume was associated with cleaning regimes with more frequent cleaners having more volume. Viscosity was associated with cleaning regimes and years of wearing with more frequent cleaning and shorter wearing time accompanying more viscous discharge. No associations were found between discharge characteristics and ethnicity, eye loss cause, hand washing, age of current prosthesis, or repolishing regimes. Forty-seven percent of ocularists’ Web sites advised that discharge was caused by surface deposits on the prosthesis, 29% by excessive handling of the prosthesis, and 24% by other causes.Conclusions: A standardized treatment

  18. [Intra-prosthetic dislocation of the Bousquet dual mobility socket].

    Science.gov (United States)

    Lecuire, F; Benareau, I; Rubini, J; Basso, M

    2004-05-01

    The Bousquet system is a dual mobility head-polyethylene polyethylene-metal cup socket. The polyethylene insert retaining the femoral head moves in the noncemented metal cup, increasing both mobility and stability. Between 1989 and 1997, seven cases of intra-prosthetic dislocation (six patients) were observed. The femoral head escaped from the polyethylene insert due to wear. On the average, this complication occurred ten Years after implantation. Risk of dislocation was high in six of the seven hips. All patients had a large sized stem screwed into the femoral neck. There was a characteristic radiological aspect with loss of the concentric head metal cup configuration. The head was applied against the upper wall of the metal cup. Surgical replacement was undertaken early in six patients by simply changing the insert without modifying the other stable components. Outcome remained good at three to eight Years. One patient underwent late surgery. The insert and the cup were replaced with a classical implant. Functional outcome was good but recurrent dislocation occurred. At mid-term, intra-prosthetic dislocation of dual mobility sockets appears to be exceptional. Dislocation results from polyethylene wear leading to failure of the insert to retain the prosthetic head. Wear is favored by direct phenomena (direct contact between neck and insert which can occur early if there is a small difference in the head and neck diameters) or indirect phenomena (factors limiting polyethylene metal-cup mobility). Surgical treatment is necessary. If undertaken early, replacement with a modular head and insert can be sufficient if the prosthesis has not loosened but the metal cup may have to be replaced in the event of metal-metal contact between the head and the cup. Prosthesis loosening, wear of the metal cup, or an identified cause of dislocation imply replacing the failing implants. Implantation of the dual mobility system is particularly interesting for patients with a high risk

  19. Production of radioiodinated prosthetic group for indirect protein labeling

    International Nuclear Information System (INIS)

    Santos, Josefina da Silva

    2001-01-01

    Monoclonal antibodies and their fragments and, more recently, radiolabeled peptides have been extensively studied in order to develop radiopharmaceuticals for diagnostic and therapy in Nuclear Medicine. The radioiodination of proteins can be done by a direct method, with radioiodine being incorporated in to a tyrosine residue of the protein by electrophilic substitution. The main problem in the use of radioiodinated proteins, is that they are often dehalogenated in vivo by the action of specific enzymes, probably because of the structural similarity between iodophenyl groups and thyroid hormones. Several protein radioiodination methods have been developed in order to minimize this in vivo dehalogenation using prosthetic groups for indirect labeling. In this case, the radioiodine is first incorporated in to the prosthetic group that is subsequently attached to a terminal amino group or to a ε-amino group of lysine residue. The aim of this work is to obtain a radioiodinated prosthetic group for indirect labeling of proteins. The prosthetic group selected was the N-succinimidyl-4-radioiodine benzoate (SIB), obtained by the iodination of the p-bromobenzoic acid followed by the reaction with TSTU (0-(N-succinimidyl)-N,N,N',N'-tetramethyl uronium tetrafluoroborate) The results of these studies showed that the p-radio iodobenzoic acid was obtained with a radiochemical purity greater than 92% and a labeling yield of about 65%. Some reaction parameters were studied like temperature, time and Cu Cl mass (cataliser). The SIB was quantitatively obtained from p-radio iodobenzoic acid, using basic medium and after removing the water from the reaction using an nitrogen stream. The kinetic of this reaction is very fast with complete consumption of the p-radioiodebenzoic acid after 5 minutes. The coupling of the SIB prosthetic group to the protein was studied using Human Immunoglobulin (IgG) as a protein model. In a comparative way, the same protein was used on direct labeling

  20. Prostanoids modulate inflammation and alloimmune responses during graft rejection

    Directory of Open Access Journals (Sweden)

    P.N. Rocha

    2005-12-01

    Full Text Available Acute rejection of a transplanted organ is characterized by intense inflammation within the graft. Yet, for many years transplant researchers have overlooked the role of classic mediators of inflammation such as prostaglandins and thromboxane (prostanoids in alloimmune responses. It has been demonstrated that local production of prostanoids within the allograft is increased during an episode of acute rejection and that these molecules are able to interfere with graft function by modulating vascular tone, capillary permeability, and platelet aggregation. Experimental data also suggest that prostanoids may participate in alloimmune responses by directly modulating T lymphocyte and antigen-presenting cell function. In the present paper, we provide a brief overview of the alloimmune response, of prostanoid biology, and discuss the available evidence for the role of prostaglandin E2 and thromboxane A2 in graft rejection.

  1. Study of radiation induced grafting of [(methacryloylamino)-propyl] trimethyl ammonium chlorite (MPTAC) on to cotton fabrics and its application

    International Nuclear Information System (INIS)

    Selambakkannu, S.

    2014-01-01

    Quaternary ammonium salt, [(methacryloylamino)-propyl] trimethyl ammonium chlorite (MPTAC) had been used as monomer in mutual radiation grafting process on cotton fabrics with the aid of high energy gamma radiation source. The polymer chains of MPTAC were successfully grafted covalently onto cotton fabrics. Effect of selected experimental variables such as irradiation dose, monomer concentration, and ambient conditions and effect of inhibitors on extent of grafting had been analyzed. Grafting yield increases steadily with monomer concentration. The highest grafting yield obtained at 2 kGy and reduces thereafter then become almost constant at higher dose range. The grafted samples characterized for its surface morphology. Finally the grafted cotton subjected to its dye uptake capacity and antibacterial efficacy. The grafted cotton fiber was used in absorption studies of aqueous basic dye solution, namely AB74. The grafted cotton posses very good dye uptake capacity. The maximum dye uptake capacity of the grafted cotton sample was 150 mg/g. Antibacterial efficacy has been tested by qualitative and quantitative methods against model bacteria S. aureus and E. coli from gram positive and gram negative respectively. 20 % grafted cotton was found to be responsible of 2 log cycle reductions for the E.coli and S.aureus colonies. (author)

  2. Novel Suicide by Division of a Chronically Infected, Externalised Axillofemoral Graft Presenting Challenges in Prehospital Assessment of Mental Capacity

    Directory of Open Access Journals (Sweden)

    Lewis G. Stevens

    2012-01-01

    Full Text Available Assessing a patient's competence to give informed consent in pre-hospital care is difficult. In the presented case an elderly patient attempted suicide by division of a chronically infected and externalised prosthetic arterial graft. He was able to comprehend his situation and understand the consequences of declining treatment. Without prior knowledge of his medical care and psychological state, however, we did not believe we could fully assess the patient's ability to act in his own best interest. After sedation and resuscitation he was transferred to hospital. This case report discusses a unique method of suicide and the challenge of obtaining valid consent in prehospital care.

  3. Clinical Effectiveness of Using Aesthetic Fixed Prosthetic Appliances with Combined Occlusal Surface

    OpenAIRE

    Andrii Biben; Zinovii Ozhohan

    2017-01-01

    The objective of the research was to evaluate the clinical effectiveness of using aesthetic fixed prosthetic appliances with combined occlusal surface. Materials and methods. The study included 30 patients who were divided into 2 groups: Group I included 20 patients with combined occlusal surface of the crowns; Group II included 22 patients with ceramic occlusal surface of the crowns. The patients were observed 3, 6 and 12 months after prosthetic repair. Results. 6 months after prosthet...

  4. LOW-MOLECULAR-WEIGHT HEPARIN TREATMENT FAILURE IN PREVENTION OF PROSTHETIC MITRAL VALVE THROMBOSIS

    OpenAIRE

    David Šuran; Vojko Kanič; Tatjana Golob Gulič; Husam Franjo Naji; Robert Lipovec

    2009-01-01

    Background Prosthetic heart valve thrombosis (PHVT) represents a dangerous postoperative complication following prosthetic heart valve replacement. Incidence varies according to different data from 0.5–4 % per year following mitral or aortic valve replacement in spite of adequate oral anticoagulation with coumarins. Case report We are presenting a case of prosthetic mitral valve thrombosis as a result of 6-month lowmolecular-weight heparin (LMWH) (nadroparine) treatment failure. Our pat...

  5. In vivo outcomes of tissue-engineered osteochondral grafts.

    Science.gov (United States)

    Bal, B Sonny; Rahaman, Mohamed N; Jayabalan, Prakash; Kuroki, Keiichi; Cockrell, Mary K; Yao, Jian Q; Cook, James L

    2010-04-01

    Tissue-engineered osteochondral grafts have been synthesized from a variety of materials, with some success at repairing chondral defects in animal models. We hypothesized that in tissue-engineered osteochondral grafts synthesized by bonding mesenchymal stem cell-loaded hydrogels to a porous material, the choice of the porous scaffold would affect graft healing to host bone, and the quality of cell restoration at the hyaline cartilage surface. Bone marrow-derived allogeneic mesenchymal stem cells were suspended in hydrogels that were attached to cylinders of porous tantalum metal, allograft bone, or a bioactive glass. The tissue-engineered osteochondral grafts, thus created were implanted into experimental defects in rabbit knees. Subchondral bone restoration, defect fill, bone ingrowth-implant integration, and articular tissue quality were compared between the three subchondral materials at 6 and 12 weeks. Bioactive glass and porous tantalum were superior to bone allograft in integrating to adjacent host bone, regenerating hyaline-like tissue at the graft surface, and expressing type II collagen in the articular cartilage.

  6. A highly selective sorbent for removal of Cr(VI) from aqueous solutions based on Fe₃O₄/poly(methyl methacrylate) grafted Tragacanth gum nanocomposite: optimization by experimental design.

    Science.gov (United States)

    Sadeghi, Susan; Rad, Fatemeh Alavi; Moghaddam, Ali Zeraatkar

    2014-12-01

    In this work, poly(methyl methacrylate) grafted Tragacanth gum modified Fe3O4 magnetic nanoparticles (P(MMA)-g-TG-MNs) were developed for the selective removal of Cr(VI) species from aqueous solutions in the presence of Cr(III). The sorbent was characterized by Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), a vibrating sample magnetometer (VSM), and thermo-gravimetric analysis (TGA). A screening study on operational variables was performed using a two-level full factorial design. Based on the analysis of variance (ANOVA) with 95% confidence limit, the significant variables were found. The central composite design (CCD) has also been employed for statistical modeling and analysis of the effects and interactions of significant variables dealing with the Cr(VI) uptake process by the developed sorbent. The predicted optimal conditions were situated at a pH of 5.5, contact time of 3.4 h, and 3.0 g L(-1) dose. The Langmuir, Freundlich, and Temkin isotherm models were used to describe the equilibrium sorption of Cr(VI) by the absorbent, and the Langmuir isotherm showed the best concordance as an equilibrium model. The adsorption process was followed by a pseudo-second-order kinetic model. Thermodynamic investigations showed that the biosorption process was spontaneous and exothermic. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Complete oral rehabilitation of a deep bite patient with Ewing’s sarcoma; surgical and prosthetic phases: A clinical report

    Directory of Open Access Journals (Sweden)

    Mehran Bahrami

    2017-01-01

    Full Text Available Introduction: Ewings sarcoma (ES is an unusual, aggressive malignant neoplasm occurring primarily in the long bones of the lower and upper extremities followed by pelvis, ribs, vertebrae, skull, and jaws-bones. Patients with ES tumor need long-term complete oral reconstruction. The location of the primary tumor in the face is predominantly in the mandible, and usually in the posterior mandible. Case Report: Here, both surgical procedures and prosthetic reconstruction in three stages of a 10-year-old childs life presented. Definitive prosthetic reconstruction is extremely challenging in such patients after previous excessive surgical resection, especially when the patient has complex dental abnormality. Fixed dental prostheses and implant-supported fixed restorations have been selected as the preferred treatment option in this case after increasing occlusal vertical dimension (OVD to create sufficient interocclusal space (IOS. Discussion: In this case, ES patient treated in three phases. In the first-stage, only surgical resection of tumor and bone graft reconstruction with titanium plate fixation was performed. In the second-stage, Lefort I surgery for maxilla with dental implants insertion in mandible was done simultaneously. For definitive restorations fabrication, it was mandatory to increase occlusal vertical dimension (OVD to create sufficient inter-occlusal space (IOS for the restorations. OVD has been altered to achieve more stable relationship of mandibular teeth with maxillary teeth, and to obtain an optimum esthetic and functional result. Several factors should be considered as determinants for increasing the OVD such as remaining tooth structure, the space available for the restorations such as the current situation, occlusal variables, and esthetics.

  8. Prosthetic Consideration in Implant-supported Prosthesis: A Review of Literature.

    Science.gov (United States)

    Gowd, Manga Snigdha; Shankar, Thatapudi; Ranjan, Rajeev; Singh, Arpita

    2017-06-01

    Modern dentistry has changed tremendously with implant therapy. For the successful implant therapy, making a proper treatment plan considering both surgical and prosthetic part in mind is the key of success. Often practitioners tend to create a treatment plan overlooking the basic principles of prosthetic part. This present review has discussed various prosthetic consideration of implant-supported prosthesis. A step-by-step detailed prosthetic option with their indications has been discussed to help all dental implant practitioners in making of an optimal treatment plan for each case.

  9. Cost analysis of debridement and retention for management of prosthetic joint infection.

    Science.gov (United States)

    Peel, T N; Dowsey, M M; Buising, K L; Liew, D; Choong, P F M

    2013-02-01

    Prosthetic joint infection remains one of the most devastating complications of arthroplasty. Debridement and retention of the prosthesis is an attractive management option in carefully selected patients. Despite this, there are no data investigating the cost of this management modality for prosthetic joint infections. The aim of this case-control study was to calculate the cost associated with debridement and retention for management of prosthetic joint infection compared with primary joint replacement surgery without prosthetic joint infection. From 1 January 2008 to 30 June 2010, there were 21 prosthetic joint infections matched to 42 control patients. Controls were matched to cases according to the arthroplasty site, age and sex. Cases had a greater number of unplanned readmissions (100% vs. 7.1%; p prosthetic joint infection the total cost, including index operation and costs of management of the prosthetic joint infection, was 3.1 times the cost of primary arthoplasty; the mean cost for cases was Australian dollars (AUD) $69,414 (±29,869) compared with $22,085 (±8147) (p prosthetic joint infections will also increase, placing significant burden on the health system. Our study adds significantly to the growing body of evidence highlighting the substantial costs associated with prosthetic joint infection. © 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

  10. Evolution of skin grafting for treatment of burns: Reverdin pinch grafting to Tanner mesh grafting and beyond.

    Science.gov (United States)

    Singh, Mansher; Nuutila, Kristo; Collins, K C; Huang, Anne

    2017-09-01

    Skin grafting is the current standard care in the treatment of full thickness burns. It was first described around 1500 BC but the vast majority of advancements have been achieved over the past 200 years. An extensive literature review was conducted on Pubmed, Medline and Google Scholar researching the evolution of skin grafting techniques. The authors concentrated on the major landmarks of skin grafting and also provide an overview of ongoing research efforts in this field. The major innovations of skin grafting include Reverdin pinch grafting, Ollier grafting, Thiersch grafting, Wolfe grafting, Padgett dermatome and modifications, Meek-wall microdermatome and Tanner mesh grafting. A brief description of the usage, advantages and limitations of each technique is included in the manuscript. Skin grafting technique have evolved significantly over past 200 years from Reverdin pinch grafting to modern day meshed skin grafts using powered dermatome. Increasing the expansion ratio and improving the cosmetic and functional outcome are the main focus of ongoing skin grafting research and emerging techniques (such as Integra ® , Recell ® , Xpansion ® ) are showing promise. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

  11. Kinetics of vein graft hyperplasia

    International Nuclear Information System (INIS)

    Zwolak, R.M.; Adams, M.C.; Clowes, A.W.

    1986-01-01

    Human aortocoronary vein grafts fail due to accelerated occlusive disease. The possibility that this is related to cellular hyperplasia was investigated in a rabbit model where kinetics of vein graft thickening, endothelial (EC) repair, and smooth muscle cell (SMC) proliferation were measured from 2 days to 24 weeks after implanting jugular vein segments in the carotid artery. Immediately after graft placement focal EC denudation was observed. These defects were repaired within 1 week and did not recur. By 4 weeks intimal area had increased 30 fold from 0.028 +/- 0.004 to 0.705 +/- 0.021 mm 2 , and a 24 weeks was 0.93 +/- 0.21 mm 2 . This response did not produce a reduction in graft lumen area. EC and SMC thymidine-labeling index were measured by en face and cross-section autoradiography after injection of 3 H-thymidine and perfusion fixation. Despite rapid EC surface repair EC labeling index remained elevated and only returned to normal levels at 12 weeks; SMC labeling was 10 fold greater than baseline even at 24 weeks (0.22% vs 0.02%). SMC mass demonstrated morphometrically increased between 2 and 12 weeks. Intimal thickening in vein grafts is due to SMC proliferation and develops after the EC layer has been restored. In contrast, intimal SMC proliferate in damaged arteries when the EC layer is absent and cease when the EC layer is regenerated

  12. Perfluorinated polymer grafting: influence of preirradiation conditions

    International Nuclear Information System (INIS)

    Moura, E.; Somessari, E.S.R.; Silveira, C.G.; Paes, H.A.; Sousa, C.A.; Fernandes, W.; Manzoli, J.E; Geraldo, A.B.; Cardozo, P.

    2009-01-01

    The technological interest of perfluorinated polymers is related to its specific properties like low chemical reactivity and high mechanical and temperature resistance. The development of polymeric membranes for PEM fuel cell dispositives requires beyond these characteristics, a long-life time performance and low cost compared to Nafion membranes. By these material have high crystallinity, the radiation grafting indeed occurs but this process generate a low mechanical resistance aggregate. In this way, it is necessary to render the polymer with a low crystallinity or even amorphous. Generally, irradiation under polymer melt temperatures makes the crystallinity breaking and polymer crosslinking. The main objective of this work was promoting the crosslinking process into perfluorinated polymers by pre-irradiation method and to precede styrene grafting by electron beam irradiation in a second step. The experimental methodology consists in pre-irradiate perfluorinated polymers films like PTFE and PFA under high temperature (> 300 deg C) and vacuum conditions by electron beam irradiation at 5 kGy to 30 kGy doses and 2,85 kGy/s to 22,4 kGy/s dose rates. To obtain temperatures above 300 deg C, it was necessary construct a vacuum chamber with a heating system where temperature process could be follow up in real time. Some molecular alterations in polymeric matrix were analyzed by Mid-ATR-FTIR spectroscopy; macroscopic changes are verified by gravimetry. The styrene grafting onto these samples is realized by electron beam irradiation at doses between 30 and 100 kGy. These results are discussed. (author)

  13. Histological evaluation of the influence of magnetic field application in autogenous bone grafts in rats

    Directory of Open Access Journals (Sweden)

    Ponzoni Deise

    2009-01-01

    Full Text Available Abstract Background Bone grafts are widely used in oral and maxillofacial reconstruction. The influence of electromagnetic fields and magnets on the endogenous stimulation of target tissues has been investigated. This work aimed to assess the quality of bone healing in surgical cavities filled with autogenous bone grafts, under the influence of a permanent magnetic field produced by in vivo buried devices. Methods Metal devices consisting of commercially pure martensitic stainless steel washers and titanium screws were employed. Thirty male Wistar rats were divided into 3 experimental and 3 control groups. A surgical bone cavity was produced on the right femur, and a bone graft was collected and placed in each hole. Two metallic washers, magnetized in the experimental group but not in the control group, were attached on the borders of the cavity. Results The animals were sacrificed on postoperative days 15, 45 and 60. The histological analysis of control and experimental samples showed adequate integration of the bone grafts, with intense bone neoformation. On days 45 and 60, a continued influence of the magnetic field on the surgical cavity and on the bone graft was observed in samples from the experimental group. Conclusion The results showed intense bone neoformation in the experimental group as compared to control animals. The intense extra-cortical bone neoformation observed suggests that the osteoconductor condition of the graft may be more susceptible to stimulation, when submitted to a magnetic field.

  14. [Redo ascending aorta replacement using a homograft for graft infection caused by methicillin-resistant Staphylococcus aureus; report of an emergently air-transferred case just after Great East Japan Earthquake].

    Science.gov (United States)

    Nakamura, Ken; Uchida, Tetsuro; Yoshimura, Yukihiro; Kim, Cholsu; Maekawa, Yoshiyuki; Minagawa, Tadanori; Mizumoto, Masahiro; Yamashita, Atsushi; Sadahiro, Mitsuaki; Saiki, Yoshikatsu; Kawamoto, Shunsuke

    2012-10-01

    We describe a case of replacement with a cryopreserved homograft for graft infection. A 48-year-old man had been performed ascending aorta replacement using woven dacron graft for type A aortic dissection. Two months ago, methicillin-resistant Staphylococcus aureus infection was suspected because of high-grade fever. Computed tomography (CT) scan revealed abscess formation around the prosthetic graft and redo operation using cryopreserved homograft was scheduled to avoid re-infection into mediastinum at Tohoku University Hospital, an institute cooperating with University of Tokyo tissue bank. However, Catastrophic Great East Japan Earthquake occurred the day before the scheduled date, and the patient could not have an operation at the institution. He was transferred to our hospital by helicopter. Then homograft was successfully implanted in ascending aorta after complete excision of infectious graft.

  15. Grafting of acrylic acid on etched latent tracks induced by swift heavy ions on polypropylene films

    International Nuclear Information System (INIS)

    Mazzei, R.; Fernandez, A.; Garcia Bermudez, G.; Torres, A.; Gutierrez, M.C.; Magni, M.; Celma, G.; Tadey, D.

    2008-01-01

    In order to continue with a systematic study that include different polymers and monomers, the residual active sites produced by heavy ion beams, that remain after the etching process, were used to start the grafting process. To produce tracks, foils of polypropylene (PP) were irradiated with 208 Pb of 25.62 MeV/n. Then, these were etched and grafted with acrylic acid (AA) monomers. Experimental curves of grafting yield as a function of grafting time with the etching time as a parameter were measured. Also, the grating yield as a function of the fluence and etching time was obtained. In addition, the permeation of solutions, with different pH, through PP grafted foils was measured

  16. Avaliação da integração de enxerto de pele com a utilização do 2-octilcianoacrilato: estudo experimental em ratos Evaluation of skin graft integration using 2-octil-cyanocrylate: experimental study in rats

    Directory of Open Access Journals (Sweden)

    Gilvani Azor de Oliveira e Cruz

    2000-01-01

    Full Text Available A fixação dos enxertos de pele total através da sutura demanda tempo cirúrgico relativamente longo. O surgimento de adesivos teciduais tem se apresentado com várias aplicações clínicas, constituindo alternativa à sutura convencional. O objetivo deste estudo é avaliar a eficácia do adesivo 2-octilcianoacrilato, quando comparado à sutura simples, na fixação de enxertos de pele total, analisando-se a integração do enxerto. Foram retirados enxertos de pele total de 1 cm², bilateralmente, do dorso de nove ratos machos, com peso médio de 150 gramas. A pele retirada para a enxertia foi recolocada sobre o defeito, a fixação foi realizada através de sutura contínua com fio monofilamentar de náilon 4-0 no lado esquerdo e adesivo de 2-octilcianoacrilato no lado direito. Os aspectos clínico e histológico da integração do enxerto foram analisados no 7º e 14º dia de pós operatório. Utilizou-se o software Sens-a-Ray para comparação de resultados. Evidenciamos maior integração do enxerto de pele total no lado do adesivo de 2-octilcianoacrilato (80% em comparação ao lado da sutura contínua (44%, sendo que houve perda total do enxerto do lado da cola de 2-octilcianoacrilato em 11,1% do casos comparado a 33,3% da sutura contínua. O tempo médio da fixação do enxerto no grupo da cola de 2-octilcianoacrilato foi de 23 segundos, contra 4 minutos da sutura convencional. Foi demonstrado uma maior integração e um menor tempo de fixação do enxerto no grupo do adesivo 2- octilcianoacrilato.Fixation of full thickness skin grafts by suture takes a long operative time. The development of tissue adhesives became an alternative for conventional suture. The aim of this study is to evaluate the efficacy of octyl-2-cyanocrylate in graft integration, compared to conventional suture in full thickness skin grafting. Two 1 cm² skin grafts were obtained billaterally from the back of 9 male rats, and then fixated over the defect, with nylon

  17. Coating of Dacron vascular grafts with an ionic polyurethane: a novel sealant with protein binding properties.

    Science.gov (United States)

    Phaneuf, M D; Dempsey, D J; Bide, M J; Quist, W C; LoGerfo, F W

    2001-03-01

    The purpose of this study was to develop a novel sealant that would seal prosthetic vascular graft interstices and be accessible for protein binding. Crimped knitted Dacron vascular grafts were cleaned (CNTRL) and hydrolyzed in boiling sodium hydroxide (HYD). These HYD grafts were sealed using an 11% solids solution of a polyether-based urethane with carboxylic acid groups (PEU-D) via a novel technique that employs both trans-wall and luminal perfusion. Carboxylic acid content, determined via methylene blue dye uptake, was 2.3- and 4.2-fold greater in PEU-D segments (1.0+/-0.27 nmol/mg) as compared to HYD and CNTRL segments, respectively. Water permeation through PEU-D graft (1.1+/-2 ml/cm2 min(-1)) was comparable to collagen-impregnated Dacron (9.8+/-10 ml/cm2 min(-1)). Non-specific 125I-albumin (125I-Alb) binding to PEU-D segments (18+/-3 ng/mg) was significantly lower than HYD and CNTRL segments. 125I-Alb linkage to PEU-D using the crosslinker EDC resulted in 5.7-fold greater binding (103+/-2 ng/mg) than non-specific PEU-D controls. However, covalent linkage of 125I-Alb to PEU-D was 4.9- and 5.9-fold less than CNTRL and HYD segments with EDC, respectively. Thus, ionic polyurethane can be applied to a pre-formed vascular graft, seal the interstices and create "anchor" sites for protein attachment.

  18. Vascularized osseous graft for scaphoid

    International Nuclear Information System (INIS)

    Mendez Daza, Carlos Hernan; Mathoulin, Cristophe

    2004-01-01

    The most commonly used technique for treatment of pseudo-arthrosis of the scaphoid is osteo-synthesis with Kirschnet wires and cortical sponge grafts. Results reported by different teams using this procedure show no more than 90% osseous consolidation, especially in cases where vascularisation of the proximal fragment of the scaphoid is compromised. Here we present a series of ten cases of pseudo-arthrosis of the scaphoid, treated using a new surgical technique involving a vascularized osseous graft of the distal radius. Using this procedure we obtained 100% consolidation, with no complications either during the procedure or immediately post-operatively. Patients returned to work in week 15 on average. In 4 cases we observed discomfort in the area of the scar, which was successfully treated using local cortisone injection. The results obtained are very similar to those seen in the literature on the different techniques for vascularized osseous grafts for pseudo-arthrosis of the scaphoid

  19. RADIOCHEMICAL YIELDS OF GRAFT POLYMERIZATION REACTIONS OF CELLULOSE

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Jr, J C; Blouin, F A

    1963-12-15

    The preparation of radioinduced graft polymers of cotton cellulose, while retaining the fibrous nature and high molecular weight of the cellulose, depended primarily on the radiochemical yields of cellulose reactions and of graft polymerization reactions. Yields of the initial major molecular changes in cellulosic polymer indicated that, in the case of scission of the molecule and carboxyl group formation, chain reactions were not initiated by radiation; however, in the case of carbonyl group formation chain reactions were initiated but quickly terminated. Generally, experimental procedures, used in graft polymerization reactions, were: simultaneous irradiation reactions, that is, application of monomers or solutions of monomers to cellulose or chemically modified celluloses, then irradiation; and post-irradiation reactions, that is, irradiation of cellulose or chemically modified celluloses, then after removal from the field of radiation, contacting the irradiated cellulose with monomer. Some of the most important factors influencing the radiochemical yields of graft polymerization reactions, of styrene and acrylonitrile onto cellulose were: concentration of monomer in treating solution; solvent; ratio of monomer solution to cellulose; prior chemical modification of cellulose; and absence of oxygen, particularly in post-irradiation reactions. Experimental data are presented, and the direct and indirect effects of Co/sup 60/ gamma radiation on these reactions are discussed. (auth)

  20. METHODOLOGY OF PROSTHETIC TREATMENT IN PATIENTS WITH MAXILLECTOMY

    Directory of Open Access Journals (Sweden)

    Ivan Gerdzhikov

    2018-06-01

    Full Text Available Aim: The aim of the described method is to present the main stages in the prosthetic treatment with hollow bulb obturator, which provides optimum defect hermetization and restoration of the damaged functions. Materials and methods: The clinical case, described is on a 70-years-old patient with edentulous jaws and maxillary defect in the right half of the upper jaw. The preliminary impressions were taken with irreversible hydrocolloid impression material, and the final impressions were taken with additive silicone material. The occlusion height and the centric relations were registered as the classical technique. After the successful trial denture appointment, the surface of the plaster master model was covered by isolation polish. After this procedure, the master model was covered by even wax layer with 5mm thickness. It was designed to be thinner in the area of the resection line. The designed cavity was filled in with silicone impression material and covered with the folio. The base plate with the arranged teeth was fixed to the model, packed in the cuvette and finished from heat-cured acrylic resin with low quantity of residual monomer. After the polymerization process, the silicone material was removed, and the obturators cap was fixed to the denture’s base plate with cold cured acrylic resin. The obturator and the complete denture of the mandible were adjusted and articulated in patient’s mouth in the final clinical stage. Results: The applied prosthetic method allowed successful defect hermetization and helped for the restoration of the speech, feeding and patient’s self-esteem. Conclusion: Prosthetic rehabilitation of patients with maxillary resection is possible only with the application of specific treatment methods.

  1. Fiber-array based optogenetic prosthetic system for stimulation therapy

    Science.gov (United States)

    Gu, Ling; Cote, Chris; Tejeda, Hector; Mohanty, Samarendra

    2012-02-01

    Recent advent of optogenetics has enabled activation of genetically-targeted neuronal cells using low intensity blue light with high temporal precision. Since blue light is attenuated rapidly due to scattering and absorption in neural tissue, optogenetic treatment of neurological disorders may require stimulation of specific cell types in multiple regions of the brain. Further, restoration of certain neural functions (vision, and auditory etc) requires accurate spatio-temporal stimulation patterns rather than just precise temporal stimulation. In order to activate multiple regions of the central nervous system in 3D, here, we report development of an optogenetic prosthetic comprising of array of fibers coupled to independently-controllable LEDs. This design avoids direct contact of LEDs with the brain tissue and thus does not require electrical and heat isolation, which can non-specifically stimulate and damage the local brain regions. The intensity, frequency, and duty cycle of light pulses from each fiber in the array was controlled independently using an inhouse developed LabView based program interfaced with a microcontroller driving the individual LEDs. While the temporal profile of the light pulses was controlled by varying the current driving the LED, the beam profile emanating from each fiber tip could be sculpted by microfabrication of the fiber tip. The fiber array was used to stimulate neurons, expressing channelrhodopsin-2, in different locations within the brain or retina. Control of neural activity in the mice cortex, using the fiber-array based prosthetic, is evaluated from recordings made with multi-electrode array (MEA). We also report construction of a μLED array based prosthetic for spatio-temporal stimulation of cortex.

  2. Dynamic Facial Prosthetics for Sufferers of Facial Paralysis

    Directory of Open Access Journals (Sweden)

    Fergal Coulter

    2011-10-01

    Full Text Available BackgroundThis paper discusses the various methods and the materialsfor the fabrication of active artificial facial muscles. Theprimary use for these will be the reanimation of paralysedor atrophied muscles in sufferers of non-recoverableunilateral facial paralysis.MethodThe prosthetic solution described in this paper is based onsensing muscle motion of the contralateral healthy musclesand replicating that motion across a patient’s paralysed sideof the face, via solid state and thin film actuators. Thedevelopment of this facial prosthetic device focused onrecreating a varying intensity smile, with emphasis ontiming, displacement and the appearance of the wrinklesand folds that commonly appear around the nose and eyesduring the expression.An animatronic face was constructed with actuations beingmade to a silicone representation musculature, usingmultiple shape-memory alloy cascades. Alongside theartificial muscle physical prototype, a facial expressionrecognition software system was constructed. This formsthe basis of an automated calibration and reconfigurationsystem for the artificial muscles following implantation, soas to suit the implantee’s unique physiognomy.ResultsAn animatronic model face with silicone musculature wasdesigned and built to evaluate the performance of ShapeMemory Alloy artificial muscles, their power controlcircuitry and software control systems. A dual facial motionsensing system was designed to allow real time control overmodel – a piezoresistive flex sensor to measure physicalmotion, and a computer vision system to evaluate real toartificial muscle performance.Analysis of various facial expressions in real subjects wasmade, which give useful data upon which to base thesystems parameter limits.ConclusionThe system performed well, and the various strengths andshortcomings of the materials and methods are reviewedand considered for the next research phase, when newpolymer based artificial muscles are constructed

  3. Grafted SiC nanocrystals

    DEFF Research Database (Denmark)

    Saini, Isha; Sharma, Annu; Dhiman, Rajnish

    2017-01-01

    ), raman spectroscopy and X-ray diffraction (XRD) measurements. UV–Visible absorption spectroscopy was used to study optical properties such as optical energy gap (Eg), Urbach's energy (Eu), refractive index (n), real (ε1) and imaginary (ε2) parts of dielectric constant of PVA as well as PVA......Polyvinyl alcohol (PVA) grafted SiC (PVA-g-SiC)/PVA nanocomposite was synthesized by incorporating PVA grafted silicon carbide (SiC) nanocrystals inside PVA matrix. In-depth structural characterization of resulting nanocomposite was carried out using fourier transform infrared spectroscopy (FTIR...

  4. Xeroderma Pigmentosum with Melanoma of Face and Its Prosthetic Management

    International Nuclear Information System (INIS)

    Sadaf, A.; Yazdanie, N.

    2013-01-01

    Xeroderma pigmentosum is a rare genetic disorder, characterized by cutaneous, ocular and neurological symptoms. Squamous cell carcinoma and melanoma are also its secondary characters. This case report is about maxillofacial prosthetic management of a 10 years old child presented with xeroderma pigmentosum. The nose of the patient was excised surgically due to melanoma. This case report elaborates the role of prosthodontist and the whole procedure of constructing the nasal prosthesis via conventional technique by using the patient's sibling nasal form as template. Regular follow up revealed marked improvement in esthetics, function and ultimately patient's quality of life. (author)

  5. Cinema and Prosthetic Memory: The Case of the Korean War

    OpenAIRE

    Keene, Judith

    2010-01-01

    This paper assesses the explanatory possibilities of the concept of prosthetic memory, with cinema as the enabler of popular understanding, when applied to the Korean War. The essay examines why it was that the conflict in Korea for many decades occupied a memory void and whether the explanations that have been offered for other similar “forgotten “wars are useful in relation to Korea. The analysis sugggests that cinema may be important in the formation of popular understanding but that th...

  6. Cinema and Prosthetic Memory: The Case of the Korean War

    Directory of Open Access Journals (Sweden)

    Judith Keene

    2010-04-01

    Full Text Available This paper assesses the explanatory possibilities of the concept of prosthetic memory, with cinema as the enabler of popular understanding, when applied to the Korean War. The essay examines why it was that the conflict in Korea for many decades occupied a memory void and whether the explanations that have been offered for other similar “forgotten “wars are useful in relation to Korea. The analysis sugggests that cinema may be important in the formation of popular understanding but that there are serious analytical drawbacks in assuming that cinema can provide a window into popular mentalities.

  7. The Role of Virtual Articulator in Prosthetic and Restorative Dentistry

    Science.gov (United States)

    Aljanakh, Mohammad

    2014-01-01

    Virtual reality is a computer based technology linked with the future of dentistry and dental practice. The virtual articulator is one such application in prosthetic and restorative dentistry based on virtual reality that will significantly reduce the limitations of the mechanical articulator, and by simulation of real patient data, allow analyses with regard to static and dynamic occlusion as well as to jaw relation. It is the purpose of this article to present the concepts and strategies for a future replacement of the mechanical articulator by a virtual one. Also, a brief note on virtual reality haptic system has been highlighted along with newly developed touch enabled virtual articulator. PMID:25177664

  8. Maxillofacial prosthetic rehalibilation of the oral cancer patient

    International Nuclear Information System (INIS)

    Wolfaardt, J.F.; Monteith, B.D.

    1982-01-01

    The victim of orofacial cancer is frequently subjected to severe morphological and functional disturbance: a condition which the maxillofacial prosthetist can do much to alleviate through the use of various prosthetic devices. The successful rehabilitation of these patients, however, is often compromised by the presence of psychosocial and other problems, the solution of which extends beyond the limits of a single clinical discipline. The modern approach to orofacial cancer, therefore, is organised within the context of interdisciplinary co-operation: each phase of patient management being planed and executed according to the co-ordinated efforts of the various members of a head and neck cancer team

  9. Development and marketing of a prosthetic urinary control valve system

    Science.gov (United States)

    Tenney, J. B., Jr.; Rabinowitz, R.; Rogers, D. W.; Harrison, H. N.

    1983-01-01

    An implantable prosthetic for the control of urinary incontinence was developed and marketed. Three phases are presented: bench development studies, animal trials, and human clinical trials. This work was performed under the direction of a Research Team at Rochester General Hospital (RGH). Bench trials were completed on prototype hardware and provided early verification of the device's ability to withstand repeated cyclic testing. Configurational variants were evaluated and a preferred design concept was established. Silicone rubber (medical grade) was selected as the preferred material for the prosthesis.

  10. Prosthetic Valve Endocarditis - Successful Management With Antimicrobial Treatment

    Directory of Open Access Journals (Sweden)

    Ashokan Nambiar C

    2015-07-01

    Full Text Available Middle aged male was admitted with high fever, rigor and chills of 2 days duration. He was seen in the clinic two years back for syncope. He gave history of Mitral (Starr-Edward and Aortic (Medtronic valve replacement ten years earlier from another center and was on regular anticoagulation with dose-adjusted acenocoumarol. On evaluation he had normal prosthetic valve function by trans-thoracic echo, but Holter monitoring showed Paroxysmal Atrial Fibrillation. He had mild wall motion abnormalities and left ventricular dysfunction suggestive of coronary artery disease also and was put on additional Metoprolol.

  11. Prosthetic valve endocarditis after transcatheter aortic valve implantation

    DEFF Research Database (Denmark)

    Olsen, Niels Thue; De Backer, Ole; Thyregod, Hans G H

    2015-01-01

    BACKGROUND: Transcatheter aortic valve implantation (TAVI) is an advancing mode of treatment for inoperable or high-risk patients with aortic stenosis. Prosthetic valve endocarditis (PVE) after TAVI is a serious complication, but only limited data exist on its incidence, outcome, and procedural......%) were treated conservatively and 1 with surgery. Four patients (22%) died from endocarditis or complications to treatment, 2 of those (11%) during initial hospitalization for PVE. An increased risk of TAVI-PVE was seen in patients with low implanted valve position (hazard ratio, 2.8 [1.1-7.2]), moderate...

  12. Xeroderma pigmentosum with melanoma of face and its prosthetic management.

    Science.gov (United States)

    Sadaf, Ayesha; Yazdanie, Nazia

    2013-10-01

    Xeroderma pigmentosum is a rare genetic disorder, characterized by cutaneous, ocular and neurological symptoms. Squamous cell carcinoma and melanoma are also its secondary characters. This case report is about maxillofacial prosthetic management of a 10 years old child presented with xeroderma pigmentosum. The nose of the patient was excised surgically due to melanoma. This case report elaborates the role of prosthodontist and the whole procedure of constructing the nasal prosthesis via conventional technique by using the patient's sibling nasal form as template. Regular follow up revealed marked improvement in esthetics, function and ultimately patient's quality of life.

  13. Transparent biocompatible sensor patches for touch sensitive prosthetic limbs

    KAUST Repository

    Nag, Anindya

    2016-12-26

    The paper presents the fabrication of transparent, flexible sensor patches developed using a casting technique with polydimethylsiloxane (PDMS) as substrate and a nanocomposite of carbon nanotubes (CNTs) and PDMS as interdigital electrodes. The electrodes act as strain sensitive capacitor. The prototypes were used as touch sensitive sensors attached to the limbs. Experiments results show the sensitivity of the patches towards tactile sensing. The results are very promising and can play a key role in the development of a cost efficient sensing system attached to prosthetic limbs.

  14. Transparent biocompatible sensor patches for touch sensitive prosthetic limbs

    KAUST Repository

    Nag, Anindya; Mukhopadhyay, Subhas; Kosel, Jü rgen

    2016-01-01

    The paper presents the fabrication of transparent, flexible sensor patches developed using a casting technique with polydimethylsiloxane (PDMS) as substrate and a nanocomposite of carbon nanotubes (CNTs) and PDMS as interdigital electrodes. The electrodes act as strain sensitive capacitor. The prototypes were used as touch sensitive sensors attached to the limbs. Experiments results show the sensitivity of the patches towards tactile sensing. The results are very promising and can play a key role in the development of a cost efficient sensing system attached to prosthetic limbs.

  15. Oral mucosa grafts for urethral reconstruction

    African Journals Online (AJOL)

    reports reveal that split and full thickness skin grafts from the scrotum, penis, extragenital sites (ureter, saphenous .... Table 1: Summary of the history of oral mucosa grafts for urethroplasty .... advised that care should be taken when suturing the.

  16. Postoperative radiographic evaluation of vascularized fibular grafts

    International Nuclear Information System (INIS)

    Manaster, B.J.; Coleman, D.A.; Bell, D.A.

    1989-01-01

    This paper reports on thirty-five patients with free vascularized fibular grafts examined postoperatively with plain radiography. Early graft incorporation is seen as a fuzziness of the cortex at the site of its insertion into the host bone. Causes of failure in grafting for bone defects include graft fracture, hardware failure, and infection. A high percentage of complications or at least delayed unions occurred when vascularized fibular grafts were used to fill defects in the lower extremity. Conversely, upper extremity defects bridged by vascularized grafts heal quickly and hypertrophy. Vascularized grafts placed in the femoral head and neck for a vascular necrosis incorporate early on their superior aspect. The osseous tunnel in which they are placed is normally wider than the graft and often becomes sclerotic; this appearance does not represent nonunion

  17. Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

    Science.gov (United States)

    Zhang, Huanxia; Li, Wei

    2015-11-01

    Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid-base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as Csbnd O, Cdbnd O, and Osbnd Cdbnd O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the plasma-grafting treatments.

  18. Triple-Layer Vascular Grafts Fabricated by Combined E-Jet 3D Printing and Electrospinning.

    Science.gov (United States)

    Huang, Ruiying; Gao, Xiangkai; Wang, Jian; Chen, Haoxiang; Tong, Chunyi; Tan, Yongjun; Tan, Zhikai

    2018-05-29

    Small-diameter tissue-engineered vascular grafts are urgently needed for clinic arterial substitute. To simulate the structures and functions of natural blood vessels, we designed a novel triple-layer poly(ε-caprolactone) (PCL) fibrous vascular graft by combining E-jet 3D printing and electrospinning techniques. The resultant vascular graft consisted of an interior layer comprising 3D-printed highly aligned strong fibers, a middle layer made by electrospun densely fibers, and an exterior structure composed of mixed fibers fabricated by co-electrospraying. The biocompatible triple-layer graft was used for in vivo implantation, and results demonstrated that the longitudinally-aligned fibers within the lumen of the graft could enhance the proliferation and migration of endothelial cells, while maintained good mechanical properties. The exterior layer provided a pathway that encouraged cells to migrate into the scaffold after implantation. This experimental graft overcame the limitations of conventionally electrospun vascular grafts of inadequate porosity and lowly cell penetration. The unique structure of the triple-layer vascular graft promoted cell growth and infiltration in vivo, thus provided an encouraging substitute for in situ tissue engineering.

  19. In Vivo Evaluation of Short-Term Performance of New Three-Layer Collagen-Based Vascular Graft Designed for Low-Flow Peripheral Vascular Reconstructions

    Directory of Open Access Journals (Sweden)

    Tomas Grus

    2018-01-01

    Full Text Available Aim. The aim of this study was to evaluate short-term patency of the new prosthetic graft and its structural changes after explantation. Methods. The study team developed a three-layer conduit composed of a scaffold made from polyester coated with collagen from the inner and outer side with an internal diameter of 6 mm. The conduit was implanted as a bilateral bypass to the carotid artery in 7 sheep and stenosis was created in selected animals. After a period of 161 days, the explants were evaluated as gross and microscopic specimens. Results. The initial flow rate (median ± IQR in grafts with and without artificial stenosis was 120±79 ml/min and 255±255 ml/min, respectively. Graft occlusion occurred after 99 days in one of 13 conduits (patency rate: 92%. Wall-adherent thrombi occurred only in sharp curvatures in two grafts. Microscopic evaluation showed good engraftment and preserved structure in seven conduits; inflammatory changes with foci of bleeding, necrosis, and disintegration in four conduits; and narrowing of the graft due to thickening of the wall with multifocal separation of the outer layer in two conduits. Conclusions. This study demonstrates good short-term patency rates of a newly designed three-layer vascular graft even in low-flow conditions in a sheep model.

  20. Prevention of primary vascular graft infection with silver-coated polyester graft in a porcine model

    DEFF Research Database (Denmark)

    Gao, H; Sandermann, J; Prag, J

    2010-01-01

    To evaluate the efficacy of a silver-coated vascular polyester graft in the prevention of graft infection after inoculation with Staphylococcus aureus in a porcine model.......To evaluate the efficacy of a silver-coated vascular polyester graft in the prevention of graft infection after inoculation with Staphylococcus aureus in a porcine model....

  1. Evaluation of Replacement Grafts and Punch Grafts in the Treatment of Vitiligo

    Directory of Open Access Journals (Sweden)

    Singh Ajit Kumar

    1980-01-01

    Full Text Available Thirtycasesof vitiligo eachwithminimum of two lesions undent replacement graft and multiple punch grafts in one lesion each. Complications observed at the recipient site like infection and raised nigosed surface were significantly more in replacement grafts. Hypopigmentation of the graft was significantly more when the disease was progressive.

  2. Osteotome-Mediated Sinus Lift without Grafting Material: A Review of Literature and a Technique Proposal

    Science.gov (United States)

    Taschieri, Silvio; Corbella, Stefano; Saita, Massimo; Tsesis, Igor; Del Fabbro, Massimo

    2012-01-01

    Implant rehabilitation of the edentulous posterior maxilla may be a challenging procedure in the presence of insufficient bone volume for implant placement. Maxillary sinus augmentation with or without using grafting materials aims to provide adequate bone volume. The aim of the present study was to systematically review the existing literature on transalveolar maxillary sinus augmentation without grafting materials and to propose and describe an osteotome-mediated approach in postextraction sites in combination with platelet derivative. The systematic review showed that high implant survival rate (more than 96% after 5 years) can be achieved even without grafting the site, with a low rate of complications. Available alveolar bone height before surgery was not correlated to survival rate. In the described case report, three implants were placed in posterior maxilla after extraction of two teeth. An osteotome-mediated sinus lifting technique was performed with the use of platelet derivative (PRGF); a synthetic bone substitute was used to fill the gaps between implant and socket walls. No complications occurred, and implants were successfully in site after 1 year from prosthetic loading. The presented technique might represent a viable alternative for the treatment of edentulous posterior maxilla with atrophy of the alveolar bone though it needs to be validated by studies with a large sample size. PMID:22792108

  3. Osteotome-Mediated Sinus Lift without Grafting Material: A Review of Literature and a Technique Proposal

    Directory of Open Access Journals (Sweden)

    Silvio Taschieri

    2012-01-01

    Full Text Available Implant rehabilitation of the edentulous posterior maxilla may be a challenging procedure in the presence of insufficient bone volume for implant placement. Maxillary sinus augmentation with or without using grafting materials aims to provide adequate bone volume. The aim of the present study was to systematically review the existing literature on transalveolar maxillary sinus augmentation without grafting materials and to propose and describe an osteotome-mediated approach in postextraction sites in combination with platelet derivative. The systematic review showed that high implant survival rate (more than 96% after 5 years can be achieved even without grafting the site, with a low rate of complications. Available alveolar bone height before surgery was not correlated to survival rate. In the described case report, three implants were placed in posterior maxilla after extraction of two teeth. An osteotome-mediated sinus lifting technique was performed with the use of platelet derivative (PRGF; a synthetic bone substitute was used to fill the gaps between implant and socket walls. No complications occurred, and implants were successfully in site after 1 year from prosthetic loading. The presented technique might represent a viable alternative for the treatment of edentulous posterior maxilla with atrophy of the alveolar bone though it needs to be validated by studies with a large sample size.

  4. [Revascularization surgery of an anuric solitary kidney using the left colic artery as a free graft].

    Science.gov (United States)

    da Gama, A Dinis; Nunes, J Silva; Cunha e Sá, Diogo; Pedro, Luís Mendes

    2003-01-01

    The thrombotic occlusion of one renal artery may become completely asymptomatic, due to the functionality of the contralateral kidney. However, in rare circumstances, such is the case of individuals with a solitary kidney, a situation of anuria and acute renal failure may constitute the main presentation of the condition. The authors report the clinical case of a 43 year old male patient, with the previous diagnosis of an infrarenal aortic occlusion and a single left kidney, who developed a thrombotic occlusion of the renal artery, with anuria and acute renal failure. The patient underwent an emergency revascularization procedure, consisting in the implantation of a prosthetic bypass graft from the superceliac aorta to the renal artery, with immediate recovery of the diuresis and renal function. Seventeen months later as a consequence of an anastomotic hyperplasia, an occlusion of the bypass graft occurred, again with anuria and acute renal failure. The patient was reoperated on and due to the inadequacy of both saphenous veins to be used as the material of choice for the revascularization procedure, a redundant segment of the left colic artery (Riolan's arcade) was removed and used as an interposition graft, from the middle colic artery to the renal artery, followed by an immediate restoration of diuresis and renal function. The singular and recurrent character of this clinical condition and the utilization of an original, eventually unique and well succeeded revascularization procedure, prompted its presentation and divulgation.

  5. [Bone graft reconstruction for posterior mandibular segment using the formwork technique].

    Science.gov (United States)

    Pascual, D; Roig, R; Chossegros, C

    2014-04-01

    Pre-implant bone graft in posterior mandibular segments is difficult because of masticatory and lingual mechanical constraints, because of the limited bone vascularization, and because of the difficulty to cover it with the mucosa. The formwork technique is especially well adapted to this topography. The recipient site is abraded with a drill. Grooves are created to receive and stabilize the grafts. The bone grafts were harvested from the ramus. The thinned cortices are assembled in a formwork and synthesized by mini-plates. The gaps are filled by bone powder collected during bone harvesting. The bone volume reconstructed with the formwork technique allows anchoring implants more than 8mm long. The proximity of the inferior alveolar nerve does not contra indicate this technique. The formwork size and its positioning on the alveolar crest can be adapted to prosthetic requirements by using osteosynthesis plates. The lateral implant walls are supported by the formwork cortices; the implant apex is anchored on the native alveolar crest. The primary stability of implants is high, and the torque is important. The ramus harvesting decreases operative risks. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  6. Spontaneous grafting of diazonium salts: chemical mechanism on metallic surfaces.

    Science.gov (United States)

    Mesnage, Alice; Lefèvre, Xavier; Jégou, Pascale; Deniau, Guy; Palacin, Serge

    2012-08-14

    The spontaneous reaction of diazonium salts on various substrates has been widely employed since it consists of a simple immersion of the substrate in the diazonium salt solution. As electrochemical processes involving the same diazonium salts, the spontaneous grafting is assumed to give covalently poly(phenylene)-like bonded films. Resistance to solvents and to ultrasonication is commonly accepted as indirect proof of the existence of a covalent bond. However, the most relevant attempts to demonstrate a metal-C interface bond have been obtained by an XPS investigation of spontaneously grafted films on copper. Similarly, our experiments give evidence of such a bond in spontaneously grafted films on nickel substrates in acetonitrile. In the case of gold substrates, the formation of a spontaneous film was unexpected but reported in the literature in parallel to our observations. Even if no interfacial bond was observed, formation of the films was explained by grafting of aryl cations or radicals on the surface arising from dediazoniation, the film growing later by azo coupling, radical addition, or cationic addition on the grafted phenyl layer. Nevertheless, none of these mechanisms fits our experimental results showing the presence of an Au-N bond. In this work, we present a fine spectroscopic analysis of the coatings obtained on gold and nickel substrates that allow us to propose a chemical structure of such films, in particular, their interface with the substrates. After testing the most probable mechanisms, we have concluded in favor of the involvement of two complementary mechanisms which are the direct reaction of diazonium salts with the gold surface that accounts for the observed Au-N interfacial bonds as well as the formation of aryl cations able to graft on the substrate through Au-C linkages.

  7. Evaluation of prosthetic heart valves by transesophageal echocardiography: problems, pitfalls, and timing of echocardiography

    NARCIS (Netherlands)

    van den Brink, Renee B. A.

    2006-01-01

    Transesophageal echocardiography (TEE) is especially suitable for examination of prosthetic valves because of the proximity of the esophagus to the heart and absence of interference with lungs and ribs. This article reviews normal and abnormal morphologic characteristics of prosthetic valves such as

  8. Utilization of penile prosthesis and male incontinence prosthetics in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Amjad Alwaal

    2017-01-01

    Conclusions: There is an increased utilization of penile prosthetics in Saudi Arabia. The private sector performs the majority of penile prosthesis procedures, and most of them are of the semirigid type. The governmental sector is more likely to perform inflatable penile prosthesis and male incontinence device procedures. Male incontinence prosthetics' use is very limited in Saudi Arabia.

  9. Prosthetic joint infection due to Lysobacter thermophilus diagnosed by 16S rRNA gene sequencing

    OpenAIRE

    B Dhawan; S Sebastian; R Malhotra; A Kapil; D Gautam

    2016-01-01

    We report the first case of prosthetic joint infection caused by Lysobacter thermophilus which was identified by 16S rRNA gene sequencing. Removal of prosthesis followed by antibiotic treatment resulted in good clinical outcome. This case illustrates the use of molecular diagnostics to detect uncommon organisms in suspected prosthetic infections.

  10. Prosthetic joint infection due to Lysobacter thermophilus diagnosed by 16S rRNA gene sequencing

    Directory of Open Access Journals (Sweden)

    B Dhawan

    2016-01-01

    Full Text Available We report the first case of prosthetic joint infection caused by Lysobacter thermophilus which was identified by 16S rRNA gene sequencing. Removal of prosthesis followed by antibiotic treatment resulted in good clinical outcome. This case illustrates the use of molecular diagnostics to detect uncommon organisms in suspected prosthetic infections.

  11. A mechanism to compensate undesired stiffness in joints of prosthetic hands

    NARCIS (Netherlands)

    Smit, G.; Plettenbrug, D.H.; Van der Helm, F.C.T.

    2014-01-01

    Background: Cosmetic gloves that cover a prosthetic hand have a parasitic positive stiffness that counteracts the flexion of a finger joint. Objectives: Reducing the required input torque to move a finger of a prosthetic hand by compensating the parasitic stiffness of the cosmetic glove. Study

  12. Reduced prosthetic stiffness lowers the metabolic cost of running for athletes with bilateral transtibial amputations.

    Science.gov (United States)

    Beck, Owen N; Taboga, Paolo; Grabowski, Alena M

    2017-04-01

    Inspired by the springlike action of biological legs, running-specific prostheses are designed to enable athletes with lower-limb amputations to run. However, manufacturer's recommendations for prosthetic stiffness and height may not optimize running performance. Therefore, we investigated the effects of using different prosthetic configurations on the metabolic cost and biomechanics of running. Five athletes with bilateral transtibial amputations each performed 15 trials on a force-measuring treadmill at 2.5 or 3.0 m/s. Athletes ran using each of 3 different prosthetic models (Freedom Innovations Catapult FX6, Össur Flex-Run, and Ottobock 1E90 Sprinter) with 5 combinations of stiffness categories (manufacturer's recommended and ± 1) and heights (International Paralympic Committee's maximum competition height and ± 2 cm) while we measured metabolic rates and ground reaction forces. Overall, prosthetic stiffness [fixed effect (β) = 0.036; P = 0.008] but not height ( P ≥ 0.089) affected the net metabolic cost of transport; less stiff prostheses reduced metabolic cost. While controlling for prosthetic stiffness (in kilonewtons per meter), using the Flex-Run (β = -0.139; P = 0.044) and 1E90 Sprinter prostheses (β = -0.176; P = 0.009) reduced net metabolic costs by 4.3-4.9% compared with using the Catapult prostheses. The metabolic cost of running improved when athletes used prosthetic configurations that decreased peak horizontal braking ground reaction forces (β = 2.786; P = 0.001), stride frequencies (β = 0.911; P < 0.001), and leg stiffness values (β = 0.053; P = 0.009). Remarkably, athletes did not maintain overall leg stiffness across prosthetic stiffness conditions. Rather, the in-series prosthetic stiffness governed overall leg stiffness. The metabolic cost of running in athletes with bilateral transtibial amputations is influenced by prosthetic model and stiffness but not height. NEW & NOTEWORTHY We measured the

  13. A computational method for comparing the behavior and possible failure of prosthetic implants

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, C.; Hollerbach, K.; Perfect, S.; Underhill, K.

    1995-05-01

    Prosthetic joint implants currently in use exhibit high Realistic computer modeling of prosthetic implants provides an opportunity for orthopedic biomechanics researchers and physicians to understand possible in vivo failure modes, without having to resort to lengthy and costly clinical trials. The research presented here is part of a larger effort to develop realistic models of implanted joint prostheses. The example used here is the thumb carpo-metacarpal (cmc) joint. The work, however, can be applied to any other human joints for which prosthetic implants have been designed. Preliminary results of prosthetic joint loading, without surrounding human tissue (i.e., simulating conditions under which the prosthetic joint has not yet been implanted into the human joint), are presented, based on a three-dimensional, nonlinear finite element analysis of three different joint implant designs.

  14. Mechanical design and performance specifications of anthropomorphic prosthetic hands: a review.

    Science.gov (United States)

    Belter, Joseph T; Segil, Jacob L; Dollar, Aaron M; Weir, Richard F

    2013-01-01

    In this article, we set forth a detailed analysis of the mechanical characteristics of anthropomorphic prosthetic hands. We report on an empirical study concerning the performance of several commercially available myoelectric prosthetic hands, including the Vincent, iLimb, iLimb Pulse, Bebionic, Bebionic v2, and Michelangelo hands. We investigated the finger design and kinematics, mechanical joint coupling, and actuation methods of these commercial prosthetic hands. The empirical findings are supplemented with a compilation of published data on both commercial and prototype research prosthetic hands. We discuss numerous mechanical design parameters by referencing examples in the literature. Crucial design trade-offs are highlighted, including number of actuators and hand complexity, hand weight, and grasp force. Finally, we offer a set of rules of thumb regarding the mechanical design of anthropomorphic prosthetic hands.

  15. Periprosthetic joint infection: are patients with multiple prosthetic joints at risk?

    Science.gov (United States)

    Jafari, S Mehdi; Casper, David S; Restrepo, Camilo; Zmistowski, Benjamin; Parvizi, Javad; Sharkey, Peter F

    2012-06-01

    Patients who present with a periprosthetic joint infection in a single joint may have multiple prosthetic joints. The risk of these patients developing a subsequent infection in another prosthetic joint is unknown. Our purposes were (1) to identify the risk of developing a subsequent infection in another prosthetic joint and (2) to describe the time span and organism profile to the second prosthetic infection. We retrospectively identified 55 patients with periprosthetic joint infection who had another prosthetic joint in place at the time of presentation. Of the 55 patients, 11 (20%) developed a periprosthetic joint infection in a second joint. The type of organism was the same as the first infection in 4 (36%) of 11 patients. The time to developing a second infection averaged 2.0 years (range, 0-6.9 years). Copyright © 2012 Elsevier Inc. All rights reserved.

  16. The caudal septum replacement graft.

    Science.gov (United States)

    Foda, Hossam M T

    2008-01-01

    To describe a technique for reconstructing the lost tip support in cases involving caudal septal and premaxillary deficiencies. The study included 120 patients with aesthetic and functional nasal problems resulting from the loss of caudal septal and premaxillary support. An external rhinoplasty approach was performed to reconstruct the lost support using a cartilaginous caudal septum replacement graft and premaxillary augmentation with Mersilene mesh. The majority of cases (75%) involved revisions in patients who had previously undergone 1 or more nasal surgical procedures. A caudal septum replacement graft was combined with premaxillary augmentation in 93 patients (77.5%). The mean follow-up period was 3 years (range, 1-12 years). The technique succeeded in correcting the external nasal deformities in all patients and resulted in a significant improvement in breathing in 74 patients (86%) with preoperative nasal obstruction. There were no cases of infection, displacement, or extrusion. The caudal septum replacement graft proved to be very effective in restoring the lost tip support in patients with caudal septal deficiency. Combining the graft with premaxillary augmentation using Mersilene mesh helped increase support and stability over long-term follow-up.

  17. ACL Graft Healing and Biologics

    NARCIS (Netherlands)

    Muller, Bart; Bowman, Karl F.; Bedi, Asheesh

    2013-01-01

    Operative reconstruction of a torn anterior cruciate ligament (ACL) has become the most broadly accepted treatment. An important, but underreported, outcome of ACL reconstruction is graft failure, which poses a challenge for the orthopedic surgeon. An understanding of the tendon-bone healing and the

  18. Polyether-polyester graft copolymer

    Science.gov (United States)

    Bell, Vernon L. (Inventor)

    1987-01-01

    Described is a polyether graft polymer having improved solvent resistance and crystalline thermally reversible crosslinks. The copolymer is prepared by a novel process of anionic copolymerization. These polymers exhibit good solvent resistance and are well suited for aircraft parts. Previous aromatic polyethers, also known as polyphenylene oxides, have certain deficiencies which detract from their usefulness. These commercial polymers are often soluble in common solvents including the halocarbon and aromatic hydrocarbon types of paint thinners and removers. This limitation prevents the use of these polyethers in structural articles requiring frequent painting. In addition, the most popular commercially available polyether is a very high melting plastic. This makes it considerably more difficult to fabricate finished parts from this material. These problems are solved by providing an aromatic polyether graft copolymer with improved solvent resistance and crystalline thermally reversible crosslinks. The graft copolymer is formed by converting the carboxyl groups of a carboxylated polyphenylene oxide polymer to ionic carbonyl groups in a suitable solvent, reacting pivalolactone with the dissolved polymer, and adding acid to the solution to produce the graft copolymer.

  19. Improvement of disintegrable properties of bone prosthetic phosphate cements

    International Nuclear Information System (INIS)

    Kaneda, Mitsumasa

    2007-01-01

    The author added a viscoelastic binder or bio-disintegrable polymer filler in αDT-cement (DTC) base, which consisting of α-tricalcium phosphate, tetracalcium phosphate and dicalcium phosphate anhydrous, in order to examine whether disintegrable properties of the bone prosthetic materials could be improved. The additive for the former binder was hydroxypropyl-cellulose and the latter filler, poly-(DL-lactide-co-glycolide) and they were mixed in various proportions with the base. At both sides of the cranial coronary suture of Japanese white rabbit, cavities (4 in total) were made at anteroposterior sites where those prosthetic cements were filled. At 1, 2 and 4 weeks later, the operated bone region was dissected out, its soft X-ray image was taken by the machine OMC603 (OHMICRON), and three-dimensional (3D) micro-focused XCT images, by Shimadzu SMX-130CT-SV. The trabecular thickness, bone volume and tissue volume ratio were calculated from the latter images by the trabecular structural measure software TRI/3Dbon (ROTAC). Disintegration rate of the cements was tested in water. Disintegrable properties were found to affect osteogenesis by giving the space for it, and thereby the choice of the ratio of the binder and disintegrable filler in the DTC makes it possible to design the most suitable cement needed. (R.T.)

  20. Illusory movement perception improves motor control for prosthetic hands.

    Science.gov (United States)

    Marasco, Paul D; Hebert, Jacqueline S; Sensinger, Jon W; Shell, Courtney E; Schofield, Jonathon S; Thumser, Zachary C; Nataraj, Raviraj; Beckler, Dylan T; Dawson, Michael R; Blustein, Dan H; Gill, Satinder; Mensh, Brett D; Granja-Vazquez, Rafael; Newcomb, Madeline D; Carey, Jason P; Orzell, Beth M

    2018-03-14

    To effortlessly complete an intentional movement, the brain needs feedback from the body regarding the movement's progress. This largely nonconscious kinesthetic sense helps the brain to learn relationships between motor commands and outcomes to correct movement errors. Prosthetic systems for restoring function have predominantly focused on controlling motorized joint movement. Without the kinesthetic sense, however, these devices do not become intuitively controllable. We report a method for endowing human amputees with a kinesthetic perception of dexterous robotic hands. Vibrating the muscles used for prosthetic control via a neural-machine interface produced the illusory perception of complex grip movements. Within minutes, three amputees integrated this kinesthetic feedback and improved movement control. Combining intent, kinesthesia, and vision instilled participants with a sense of agency over the robotic movements. This feedback approach for closed-loop control opens a pathway to seamless integration of minds and machines. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  1. Fungal prosthetic valve endocarditis with mycotic aneurysm: Case report.

    Science.gov (United States)

    Brandão, Mariana; Almeida, Jorge; Ferraz, Rita; Santos, Lurdes; Pinho, Paulo; Casanova, Jorge

    2016-09-01

    Fungal prosthetic valve endocarditis is an extremely severe form of infective endocarditis, with poor prognosis and high mortality despite treatment. Candida albicans is the most common etiological agent for this rare but increasingly frequent condition. We present a case of fungal prosthetic valve endocarditis due to C. albicans following aortic and pulmonary valve replacement in a 38-year-old woman with a history of surgically corrected tetralogy of Fallot, prior infective endocarditis and acute renal failure with need for catheter-based hemodialysis. Antifungal therapy with liposomal amphotericin B was initiated prior to cardiac surgery, in which the bioprostheses were replaced by homografts, providing greater resistance to recurrent infection. During hospitalization, a mycotic aneurysm was diagnosed following an episode of acute arterial ischemia, requiring two vascular surgical interventions. Despite the complications, the patient's outcome was good and she was discharged on suppressive antifungal therapy with oral fluconazole for at least a year. The reported case illustrates multiple risk factors for fungal endocarditis, as well as complications and predictors of poor prognosis, demonstrating its complexity. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. Candida Prosthetic Joint Infection. A Review of Treatment Methods.

    Science.gov (United States)

    Cobo, Fernando; Rodríguez-Granger, Javier; Sampedro, Antonio; Aliaga-Martínez, Luis; Navarro-Marí, José María

    2017-01-01

    Fungal microorganisms are still a rare cause of bone and joint infections. We report a new case of knee prosthetic joint infection due to Candida albicans in a patient with a previous two-stage right knee arthroplasty for septic arthritis due to S. epidermidis occurred several months ago. Moreover, the treatment in 76 cases of Candida prosthetic joint infection has been discussed. Forty patients were female and mean age at diagnosis was 65.7 (± SD 18) yrs. No risk factors for candidal infection were found in 25 patients. Infection site was the knee in 38 patients and hip in 36; pain was present in 44 patients and swelling in 24. The most frequent species was C. albicans , followed by C. parapsilosis . Eleven patients were only treated with antifungal drugs being the outcome favourable in all of them. Two-stage exchange arthroplasty was performed in 30 patients, and resection arthroplasty in other 30; in three patients one-stage exchange arthroplasty was done. A favourable outcome was found in 58 patients after antifungal plus surgical treatment, in 11 after antifungal treatment alone and in one after surgery alone. The type of treatment is still not clearly defined and an algorithm for treatment in fungal PJI should be established, but various types of surgical procedures may be applied.

  3. Rapid Molecular Microbiologic Diagnosis of Prosthetic Joint Infection

    Science.gov (United States)

    Cazanave, Charles; Greenwood-Quaintance, Kerryl E.; Hanssen, Arlen D.; Karau, Melissa J.; Schmidt, Suzannah M.; Gomez Urena, Eric O.; Mandrekar, Jayawant N.; Osmon, Douglas R.; Lough, Lindsay E.; Pritt, Bobbi S.; Steckelberg, James M.

    2013-01-01

    We previously showed that culture of samples obtained by prosthesis vortexing and sonication was more sensitive than tissue culture for prosthetic joint infection (PJI) diagnosis. Despite improved sensitivity, culture-negative cases remained; furthermore, culture has a long turnaround time. We designed a genus-/group-specific rapid PCR assay panel targeting PJI bacteria and applied it to samples obtained by vortexing and sonicating explanted hip and knee prostheses, and we compared the results to those with sonicate fluid and periprosthetic tissue culture obtained at revision or resection arthroplasty. We studied 434 subjects with knee (n = 272) or hip (n = 162) prostheses; using a standardized definition, 144 had PJI. Sensitivities of tissue culture, of sonicate fluid culture, and of PCR were 70.1, 72.9, and 77.1%, respectively. Specificities were 97.9, 98.3, and 97.9%, respectively. Sonicate fluid PCR was more sensitive than tissue culture (P = 0.04). PCR of prosthesis sonication samples is more sensitive than tissue culture for the microbiologic diagnosis of prosthetic hip and knee infection and provides same-day PJI diagnosis with definition of microbiology. The high assay specificity suggests that typical PJI bacteria may not cause aseptic implant failure. PMID:23658273

  4. Leukocyte and bacteria imaging in prosthetic joint infection

    Directory of Open Access Journals (Sweden)

    AWJM Glaudemans

    2013-01-01

    Full Text Available There has been a significant increase in the number of joint prosthesis replacements worldwide. Although relatively uncommon, complications can occur with the most serious being an infection. Various radiological and nuclear imaging techniques are available to diagnose prosthetic joint infections (PJI. In this review article, we describe the pathophysiology of PJI, the principles of nuclear medicine imaging and the differences between Single Photon Emission Computed Tomography (SPECT and Positron Emission Tomography (PET. The value of nuclear medicine techniques for clinical practice is also discussed.Then we provide an overview of the most often used radionuclide imaging techniques that may be helpful in diagnosing prosthetic joint infection: the 67Ga-citrate, labelled white blood cells in vitro and in vivo (monoclonal antibodies directed against specific targets on the leukocytes, and 18F-fluorodeoxyglucose (18F-FDG. We describe their working methods, the pitfalls, and the interpretation criteria. Furthermore, we review recent advances in imaging bacteria, a molecular imaging method that holds promises for the detection of occult infections. We conclude proposing two diagnostic flow-charts, based on data in the literature, that could help the clinicians to choose the best nuclear imaging method when they have a patient with suspicion of or with proven PJI.

  5. Indium-granulocyte scanning in the painful prosthetic joint

    International Nuclear Information System (INIS)

    Pring, D.J.; Henderson, R.G.; Keshavarzian, A.; Rivett, A.G.; Krausz, T.; Coombs, R.R.; Lavender, J.P.

    1986-01-01

    The value of indium-111-labeled granulocyte scanning to determine the presence of infection was assessed in 50 prosthetic joints (41 of which were painful) in 40 patients. Granulocytes were obtained from the patients' blood and labeled in plasma with indium 111 tropolonate. Abnormal accumulation of indium 111 in the region of the prosthesis was noted. Proven infection occurred in 11 prostheses, and all of the infections were detected by indium-111-labeled granulocyte scanning. Nineteen were not infected (including nine asymptomatic controls) and only two produced false-positive scans. This represents a specificity of 89.5%, sensitivity of 100%, and overall accuracy of 93.2%. These results compare favorably with plain radiography. There was no radiologic evidence of infection in three of the infected prostheses, and 10 of the noninfected prostheses had some radiologic features that suggested sepsis. We conclude that indium-granulocyte scanning can reliably detect or exclude infection in painful prosthetic joints and should prove useful in clinical management

  6. Ureaplasma parvum prosthetic joint infection detected by PCR.

    Science.gov (United States)

    Farrell, John J; Larson, Joshua A; Akeson, Jeffrey W; Lowery, Kristin S; Rounds, Megan A; Sampath, Rangarajan; Bonomo, Robert A; Patel, Robin

    2014-06-01

    We describe the first reported case of Ureaplasma parvum prosthetic joint infection (PJI) detected by PCR. Ureaplasma species do not possess a cell wall and are usually associated with colonization and infection of mucosal surfaces (not prosthetic material). U. parvum is a relatively new species name for certain serovars of Ureaplasma urealyticum, and PCR is useful for species determination. Our patient presented with late infection of his right total knee arthroplasty. Intraoperative fluid and tissue cultures and pre- and postoperative synovial fluid cultures were all negative. To discern the pathogen, we employed PCR coupled with electrospray ionization mass spectrometry (PCR/ESI-MS). Our patient's failure to respond to empirical antimicrobial treatment and our previous experience with PCR/ESI-MS in culture-negative cases of infection prompted us to use this approach over other diagnostic modalities. PCR/ESI-MS detected U. parvum in all samples. U. parvum-specific PCR testing was performed on all synovial fluid samples to confirm the U. parvum detection. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  7. Consumer satisfaction with the services of prosthetics and orthotics facilities.

    Science.gov (United States)

    Bosmans, Joline; Geertzen, Jan; Dijkstra, Pieter U

    2009-03-01

    Consumer satisfaction with the services provided in a prosthetics and orthotics (P&O) facility has seldom been studied. The aim of this study was to analyze consumer satisfaction regarding the services provided by 15 P&O facilities in The Netherlands. Consumers (n = 1,364) of these P&O facilities who were fitted with a prosthesis, orthopaedic shoes, an orthosis, or another device, were asked to rate the overall services provided and whether they were satisfied with the device provided and its delivery time. Additionally, they filled in a modified SERVQUAL questionnaire (see Appendix). Consumers gave the service provided by P&O facilities a mean overall rating of 8.1. The highest ratings were given by consumers fitted with a prosthesis (mean overall rating of services: 8.4). In total, 78% of the consumers were satisfied with the device provided and 93% with the delivery time. The results of our study showed that, on the SERVQUAL, 50% of the statements fulfilled the criteria for a satisfactory quality of the services. The overall consumer rating of the service provided by P&O facilities is high and depends on the device provided. The outcomes on the SERVQUAL were moderate. In future, it is important to study consumer satisfaction more extensively in order to improve the quality of P&O services in daily practice. Additionally, specific questionnaires need to be developed to measure all aspects of prosthetic and orthotic care, with the aim to improve the services.

  8. Endovascular repair of an innominate artery pseudoaneurysm using the Valiant Mona LSA branched graft device

    Directory of Open Access Journals (Sweden)

    Josh A. Sibille, MD

    2017-03-01

    Full Text Available A 60-year-old woman involved in a motor vehicle collision presented with a traumatic pseudoaneurysm of the innominate artery origin in addition to multiple concomitant injuries. She was classified as a high-risk candidate for open repair. An experimental thoracic branched graft device was used for coverage of the injury with the addition of a right carotid-to-left carotid-to-left subclavian artery bypass. Follow-up imaging showed resolution of the pseudoaneurysm and patency of her bypass grafts. This is the first described use of the Mona LSA Branch Thoracic Stent Graft System (Medtronic, Minneapolis, Minn in the innominate artery.

  9. Prosthetic valves in adult patients with congenital heart disease : Rationale and design of the Dutch PROSTAVA study

    NARCIS (Netherlands)

    Freling, H. G.; van Slooten, Y. J.; van Melle, J. P.; Mulder, B. J. M.; van Dijk, A. P. J.; Hillege, H. L.; Post, M. C.; Sieswerda, G. Tj; Jongbloed, M. R. M.; Willems, T. P.; Pieper, P. G.

    2012-01-01

    Data on long-term complications in adult patients with congenital heart disease (ACHD) and a prosthetic valve are scarce. Moreover, the influence of prosthetic valves on quality of life (QoL) and functional outcome in ACHD patients with prosthetic valves has not been studied. The primary objective

  10. 38 CFR 17.122 - Payment or reimbursement of the expenses of repairs to prosthetic appliances and similar devices...

    Science.gov (United States)

    2010-07-01

    ... of the expenses of repairs to prosthetic appliances and similar devices furnished without prior... Payment or reimbursement of the expenses of repairs to prosthetic appliances and similar devices furnished without prior authorization. The expenses of repairs to prosthetic appliances, or similar appliances...

  11. A qualitative study of the challenges of providing pre-prosthetic rehabilitation in rural South Africa.

    Science.gov (United States)

    Ennion, Liezel; Johannesson, Anton

    2018-04-01

    There is a known shortage of rehabilitation staff in rural settings and a sharp increase in the number of lower limb amputations being performed. A lack of adequate pre-prosthetic rehabilitation will result in worse physical and psychological outcomes for a person with a lower limb amputation, and they will not be eligible to be fitted with a prosthesis. To explore therapists' experiences with providing pre-prosthetic rehabilitation in a rural setting. A qualitative descriptive approach was used to collect and analyse data. Data were collected from 17 purposively sampled therapists in five district hospitals in a rural community in South Africa. Data were collected in two rounds of focus groups to explore the challenges of providing pre-prosthetic rehabilitation in rural South Africa. The main themes identified in the study were (1) a lack of government health system support, (2) poor socioeconomic circumstances of patients and (3) cultural factors that influence rehabilitation. These themes all negatively influence the therapists' ability to follow up patients for pre-prosthetic rehabilitation after discharge from hospital. A lack of adequate pre-prosthetic rehabilitation is a substantial barrier to prosthetic fitting in rural South Africa. Patients who do not receive pre-prosthetic rehabilitation have a poorly shaped residuum or other complications such as knee or hip joint contractures which disqualifies them from being referred to prosthetic services. Therapists involved in this study identified the most important barriers to patients having access to prosthetic services. Clinical relevance Pre-prosthetic rehabilitation provides care of the residuum; maintenance or improvement of physical strength, joint range of motion and referral to a prosthetist. By exploring the challenges known to exist in this service, we can identify potential ways to reduce these barriers and improve the lives of those who use it.

  12. Increasing the Thermal Conductivity of Graphene-Polyamide-6,6 Nanocomposites by Surface-Grafted Polymer Chains: Calculation with Molecular Dynamics and Effective-Medium Approximation.

    Science.gov (United States)

    Gao, Yangyang; Müller-Plathe, Florian

    2016-02-25

    By employing reverse nonequilibrium molecular dynamics simulations in a full atomistic resolution, the effect of surface-grafted chains on the thermal conductivity of graphene-polyamide-6.6 (PA) nanocomposites has been investigated. The interfacial thermal conductivity perpendicular to the graphene plane is proportional to the grafting density, while it first increases and then saturates with the grafting length. Meanwhile, the intrinsic in-plane thermal conductivity of graphene drops sharply as the grafting density increases. The maximum overall thermal conductivity of nanocomposites appears at an intermediate grafting density because of these two competing effects. The thermal conductivity of the composite parallel to the graphene plane increases with the grafting density and grafting length which is attributed to better interfacial coupling between graphene and PA. There exists an optimal balance between grafting density and grafting length to obtain the highest interfacial and parallel thermal conductivity. Two empirical formulas are suggested, which quantitatively account for the effects of grafting length and density on the interfacial and parallel thermal conductivity. Combined with effective medium approximation, for ungrafted graphene in random orientation, the model overestimates the thermal conductivity at low graphene volume fraction (f 10%). For unoriented grafted graphene, the model matches the experimental results well. In short, this work provides some valuable guides to obtain the nanocomposites with high thermal conductivity by grafting chain on the surface of graphene.

  13. Homogeneous cation exchange membrane by radiation grafting

    International Nuclear Information System (INIS)

    Kolhe, Shailesh M.; G, Agathian; Ashok Kumar

    2001-01-01

    Preparation of a strong cation exchange membrane by radiation grafting of styrene on to polyethylene (LDPE) film by mutual irradiation technique in the presence of air followed by sulfonation is described. The grafting has been carried out in the presence of air and without any additive. Low dose rate has been seen to facilitate the grafting. Further higher the grafting percentage more is the exchange capacity. The addition of a swelling agent during the sulfonation helped in achieving the high exchange capacity. The TGA-MASS analysis confirmed the grafting and the sulfonation. (author)

  14. Fluxional behavior of molecular WMe6 and of silica grafted WMe6

    KAUST Repository

    Credendino, Raffaele; Vignola, Emanuele; Poater, Albert; Callens, Emmanuel; Basset, Jean-Marie; Cavallo, Luigi

    2015-01-01

    Using DFT methods we describe the fluxional behavior of mono-, bi-, and tripodal W(CH3)6 species grafted on partially dehydroxylated silica. Our results show that the umbrella inversion mechanism described to explain the fluxionality of the parent W(CH3)6 molecule is not operative after grafting on silica. Low-energy turnstile rotations are instead operative for all considered species, correlating the experimental values found in solid-state NMR.

  15. Fluxional behavior of molecular WMe6 and of silica grafted WMe6

    KAUST Repository

    Credendino, Raffaele

    2015-02-09

    Using DFT methods we describe the fluxional behavior of mono-, bi-, and tripodal W(CH3)6 species grafted on partially dehydroxylated silica. Our results show that the umbrella inversion mechanism described to explain the fluxionality of the parent W(CH3)6 molecule is not operative after grafting on silica. Low-energy turnstile rotations are instead operative for all considered species, correlating the experimental values found in solid-state NMR.

  16. Daptomycin treatment in Gram-positive vascular graft infections

    Directory of Open Access Journals (Sweden)

    Francisco Arnaiz de las Revillas

    2018-03-01

    Full Text Available Background: Daptomycin is a bactericidal antibiotic approved for the treatment of skin and soft tissue infections and right-side endocarditis. However, there is a lack of published data outlining its usefulness in vascular graft infections (VGI. The aim of this study was to describe the clinical experience of daptomycin use in the treatment of VGI caused by Gram-positive bacteria. Methods: This was a retrospective cohort study of patients diagnosed with VGI receiving daptomycin at a tertiary care hospital during the period January 2010 to December 2012. Results: Of a total 1066 consecutive patients who had undergone vascular grafts (VG, 25 were diagnosed with VGI. Fifteen of these patients (11 prosthetic VG, three autologous VG, one both types received daptomycin (median dose 6.7 mg/kg/day, range 4.1–7.1 mg/kg/day; median age 69 years, range 45–83 years; 80% male. The infected bypass was removed in 13 cases. The most common reason for selecting daptomycin was kidney failure (53%. The Gram-positive organisms isolated were coagulase-negative Staphylococcus (n = 10, Staphylococcus aureus (n = 3 (two methicillin-resistant S. aureus, Enterococcus faecium (n = 2, and Enterococcus faecalis (n = 1. The mean follow-up was 69 months (interquartile range 48–72 months. Ten patients (66.7% achieved complete healing of the VGI. A recurrence of the infection was observed in 100% of patients in whom the bypass was not removed. Among patients who did not achieve complete healing, one needed a supracondylar amputation and one died as a consequence of infection. Five patients received treatment with rifampicin in addition to daptomycin and they were all cured. Conclusions: The use of daptomycin and surgery for Gram-positive VGI was effective and well tolerated, and this may be a good alternative for the treatment of VGI in patients with peripheral arterial disease in whom renal insufficiency is common. Keywords: Daptomycin, Gram-positive, Vascular

  17. Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Huanxia, E-mail: zhanghuanxia818@163.com [College of Materials and Textile Engineering, Jiaxing University, Jiaxing 314001, Zhejiang (China); Li, Wei [College of Textile Engineering, Donghua University, Shanghai 201620 (China); Key Laboratory of Textile Science and Technology, Ministry of Education, Shanghai 201620 (China)

    2015-11-30

    Graphical abstract: - Highlights: • A simple method to improve surface properties is applied to carbon fibers. • The maleic anhydride was grafted onto the carbon fiber with the FTIR spectra. • The plasma treatment time and polymerization condition affected on the grafting rate. • The carbon fibers exhibited excellent surface hydrophilicity and IFSS properties. - Abstract: Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid–base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR–ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as C−O, C=O, and O−C=O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the

  18. Plasma-grafting polymerization on carbon fibers and its effect on their composite properties

    International Nuclear Information System (INIS)

    Zhang, Huanxia; Li, Wei

    2015-01-01

    Graphical abstract: - Highlights: • A simple method to improve surface properties is applied to carbon fibers. • The maleic anhydride was grafted onto the carbon fiber with the FTIR spectra. • The plasma treatment time and polymerization condition affected on the grafting rate. • The carbon fibers exhibited excellent surface hydrophilicity and IFSS properties. - Abstract: Interfacial adhesion between matrix and fibers plays a crucial role in controlling the performance of composites. Carbon fibers have the major constraint of chemical interness and hence have limited adhesion with the matrix. Surface treatment of fibers is the best solution to this problem. In this work, carbon fibers were activated by plasma and grafting polymerization. The grafting ratio of polymerization was obtained by acid–base titration. The chemical and physical changes induced by the treatments on carbon fiber surface was examined using contact angle measurements, X-ray photoelectron spectroscopy (XPS), and Fourier-transform infrared spectroscopy-attenuated total reflectance (FTIR–ATR) technique. The interfacial adhesion of CF/EP (carbon fiber/epoxy) composites were analyzed by a single fiber composite (SFC) for filament fragmentation test. Experimental results show that the grafting rate was not only the function of the plasma-treat time but also the concentration of the grafting polymerization. The oxygen-containing groups (such as C−O, C=O, and O−C=O) and the interfacial shear strength (IFSS) of the plasma-grafting carbon fiber increased more significantly than the carbon fiber without plasma treatment grafted with MAH. This demonstrates that the surfaces of the carbon fiber samples are more active, hydrophilic, and rough after plasma-grafting treatments using a DBD operating in ambient argon mixture with oxygen. With DBD (dielectric barrier discharges) operating in ambient argon mixture with oxygen, the more active, hydrophilic, and rough surface was obtained by the

  19. The effect of platelet-rich plasma on composite graft survival.

    Science.gov (United States)

    Jeon, Yeo Reum; Kang, Eun Hye; Yang, Chae Eun; Yun, In Sik; Lee, Won Jai; Lew, Dae Hyun

    2014-08-01

    Composite grafts are suitable for facial reconstruction because of good color matching, low donor-site morbidity, acceptable texture, and easy surgical techniques. However, their use is limited to small defects and by unpredictable survival rates. As platelet-rich plasma contains large numbers of growth factors and has been widely used for tissue regeneration, this study aimed to investigate platelet-rich plasma as an adjuvant to enhance composite graft survival. Twenty New Zealand White rabbits were used, and chondrocutaneous composite grafts were applied to their ears. The grafts were then returned to their original positions after rotation to block the original circulation from the base of the graft. Each of the individual ears was assigned randomly into one of two groups: experimental (n=20; platelet-rich plasma group) or control (n=20; control group). The surrounding skin of the composite graft was injected with either 1.0 ml of platelet-rich plasma derived from autologous whole blood in the platelet-rich plasma group or normal saline in the control group. Graft survival, cutaneous blood flow, CD31-stained vessels, and vascular endothelial growth factor protein levels were examined. Twelve days after surgery, graft viability in the platelet-rich plasma group was higher than in the control group. Blood perfusion was also higher in the platelet-rich plasma group. Compared with the control group, the number of CD31 blood vessels and vascular endothelial growth factor expression levels were significantly increased in the platelet-rich plasma group. The authors' results suggest that platelet-rich plasma restores the perfusion of composite grafts by enhancing revascularization and may exert therapeutic effects on the survival of composite grafts.

  20. Studies on radiation-induced graft polymerization

    International Nuclear Information System (INIS)

    Omichi, Hideki

    1978-09-01

    Radiation-induced graft polymerization is used extensively to improve physical properties of polymers, but few processes are now commercialized. The reason for this is partly inadequate basic research on the reaction and partly the difficulty in developing the grafting process with large radiation source. Firstly, new techniques are proposed of studying kinetics of the graft polymerization in heterogeneous system. Based on the grafting yield, the molecular weight of graft chains, and the amount of radicals given by ESR and activation analysis, kinetic parameters are obtained and the reaction mechanism of grafting process is discussed. Secondly, the development of grafting process of poly (vinyl chloride)-butadiene is described. By study of the reaction, process design, construction and operation of the pilot plant, and economic analysis of the process, this process with 60 Co gamma ray sources is shown to be industrially promising. (author)