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Sample records for 10-0 polypropylene suture

  1. 21 CFR 878.5010 - Nonabsorbable polypropylene surgical suture.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 false Nonabsorbable polypropylene surgical suture. 878.5010... § 878.5010 Nonabsorbable polypropylene surgical suture. (a) Identification. Nonabsorbable polypropylene surgical suture is a...

  2. Selective laser vaporization of polypropylene sutures and mesh

    Science.gov (United States)

    Burks, David; Rosenbury, Sarah B.; Kennelly, Michael J.; Fried, Nathaniel M.

    2012-02-01

    Complications from polypropylene mesh after surgery for female stress urinary incontinence (SUI) may require tedious surgical revision and removal of mesh materials with risk of damage to healthy adjacent tissue. This study explores selective laser vaporization of polypropylene suture/mesh materials commonly used in SUI. A compact, 7 Watt, 647-nm, red diode laser was operated with a radiant exposure of 81 J/cm2, pulse duration of 100 ms, and 1.0-mm-diameter laser spot. The 647-nm wavelength was selected because its absorption by water, hemoglobin, and other major tissue chromophores is low, while polypropylene absorption is high. Laser vaporization of ~200-?m-diameter polypropylene suture/mesh strands, in contact with fresh urinary tissue samples, ex vivo, was performed. Non-contact temperature mapping of the suture/mesh samples with a thermal camera was also conducted. Photoselective vaporization of polypropylene suture and mesh using a single laser pulse was achieved with peak temperatures of 180 and 232 °C, respectively. In control (safety) studies, direct laser irradiation of tissue alone resulted in only a 1 °C temperature increase. Selective laser vaporization of polypropylene suture/mesh materials is feasible without significant thermal damage to tissue. This technique may be useful for SUI procedures requiring surgical revision.

  3. Evaluation of endoscopic laser excision of polypropylene mesh/sutures following anti-incontinence procedures.

    LENUS (Irish Health Repository)

    Davis, N F

    2012-11-01

    We reviewed our experience with and outcome of the largest series to our knowledge of patients who underwent endoscopic laser excision of eroded polypropylene mesh or sutures as a complication of previous anti-incontinence procedures.

  4. Polypropylene Suture Versus Skin Staples for Securing Mesh in Lichtenstein Inguinal Hernioplasty

    International Nuclear Information System (INIS)

    Objective: To compare polypropylene suture and skin staples for securing mesh in Lichtenstein inguinal hernioplasty in terms of mean operating time and postoperative pain. Study Design: Randomized clinical trial. Place and Duration of Study: Surgical Ward, Combined Military Hospital, Kharian, from August 2011 to February 2012. Methodology: All individuals fulfilling inclusion criteria underwent elective Lichtenstein inguinal hernioplasty as admitted patients, under spinal anaesthesia and with aseptic measures. In group 1, during the operation, mesh fixation was done with 2/0 polypropylene suture and skin was closed with subcuticular 2/0 polypropylene suture whereas in group 2, the anchorage of mesh was done with skin staples and skin was closed with staples from the same stapler. Mean operative time and postoperative pain, assessed on a visual analog score, were compared between the groups. Results: The overall postoperative pain was lower (p = 0.026) when staples were used to anchor mesh. Moreover, operative time was also lower (37.42 A +- 2.69 minutes) in staple group versus (42.44 A +- 2.55 minutes in polypropylene group). Conclusion: Mean operating time and postoperative pain is less in securing mesh with skin staples as compared to polypropylene suture in Lichtenstein inguinal hernioplasty. (author)

  5. Creep rupture behavior of polypropylene suture material and its applications as a time-release mechanism

    International Nuclear Information System (INIS)

    The controlled failure of polypropylene (PP) sutures is studied via creep rupture tests. From plots of log time (tB) vs. stress (sigma), linear relationships are generated over the failure times of 1-1000 h. Results show that as a function of stress, the time dependence varies with irradiation dose (15, 20, 25, and 50 Mrad), irradiation atmosphere (air and vacuum), suture diameter (7-0, 6-0, 5-0, and 4-0), and test temperature (26 and 37 degrees C). For a given stress, the time to failure is least for the greatest dose in the presence of air and at the highest temperature. When suture loops are wrapped around a small wire sheave, however, failure occurs in the largest suture as much as two decades sooner than the smallest suture studied. Within the limitations stated herein, they are independent of test method, loop diameter, aging, and humidity. Consequently, after irradiation in vacuum and postirradiation heat treatment, the processed material may be stored at room temperature for at least 1 month. Such materials are advocated when the time release of a dental or medical device is required, for example, in the self-activating cleft palate appliance

  6. Polypropylene

    International Nuclear Information System (INIS)

    This book gives description of polypropylene with history, polypropylene chemistry such as polymerization reaction and manufacture method of polypropylene, structure and property of polypropylene like molecular weight, melt flow index and property of inter polymer, property of polypropylene the position of polypropylene among plastic and functional property of polypropylene, ageing resistance of polypropylene, processing of polypropylene like injection molding film and type use of polypropylene with using cases.

  7. Gross and Histologic Evaluation of Abdominal Adhesions Associated with Chromic Catgut and Polypropylene Sutured Enteropexies in Dog Evaluación Macroscópica e Histológica de las Adherencias Abdominales Asociadas a Enteropexias Suturadas con Catgut Crómico y Polipropileno en Perros

    Directory of Open Access Journals (Sweden)

    J. F Akinrinmade

    2010-12-01

    Full Text Available The gross and histologic patterns of abdominal adhesions formed by the use of chromic catgut and polypropylene suture materials were evaluated in dogs. Gross and histologic examinations did not reveal significant difference (p>0.05 in the degree of adhesions observed at enteropexy sites in both suture materials. The use of polypropylene with superior suture qualities should be considered instead of chromic catgut for procedures in which adhesion is desired in the dog.Fueron evaluados los patrones macroscópicos e histológicos de las adherencias abdominales formadas por el uso de catgut crómico y materiales de sutura de polipropileno. Los exámenes macroscópicos e histológicos no revelaron diferencias significativas (p> 0,05 en el grado de adherencias observadas en los sitios de la enteropexia en ambos materiales de sutura. El uso de suturas de polipropileno con mejores cualidades debe ser considerado en lugar del catgut cromado para procedimientos en los que la adherencia en el perro es deseada.

  8. A Prospective Randomized Study Comparing Skin Staples and Polypropylene Sutures for Securing the Mesh in Lichtenstein's Repair

    Directory of Open Access Journals (Sweden)

    Pankaj Shivhare

    2014-06-01

    Results: Mesh fixation with skin staples is as effective as conventional sutures with the added advantage of significant reduction in the operating time and complications. Conclusions: The staples can be applied much more quickly than sutures for fixing the mesh, thus saving the operating time. The infection rate is significantly decreased with staples. The staples are not associated with any significant complications or recurrence. [Arch Clin Exp Surg 2014; 3(3.000: 147-152

  9. Sutura arterial com técnicas contínua e de pontos separados, utilizando-se os fios polipropilene e polidioxanone: estudo experimental em coelhos Arterial suture with continuous and interrupted techniques, using polypropylene and polydioxanone threads: experimental study in rabbits

    Directory of Open Access Journals (Sweden)

    Nelson Leonardo Kerdahi Leite de Campos

    2003-10-01

    Full Text Available OBJETIVO: Observar o comportamento da sutura arterial em aortas abdominais de coelhos em crescimento, comparando-se as técnicas contínua e com pontos separados, empregando-se dois tipos de fios: Polipropilene 7-0 (inabsorvível e Polidioxanone 7-0 (absorvível. MÉTODOS: Grupos: GI - Controle (sem sutura; GII - Polipropilene, Pontos Separados; GIII - Polipropilene, Contínua; GIV - Polidioxanone, Pontos Separados e GV - Polidioxanone, Contínua. Cada grupo foi subdividido em quatro Momentos de Eutanásia: aos 7, 14, 30 e 60 dias de pós-operatório. Foram avaliados: peso dos animais, diâmetros e pulsos arteriais, estenose, trombose, aderências, aortografia, visibilidade do fio, cicatrização e microscopia. RESULTADOS: a após 60 dias, o local da linha de sutura cresceu de forma significativa em todos os grupos; b a técnica de sutura com pontos separados causou menor estenose da linha de sutura, observada tanto no ato cirúrgico, como na eutanásia dos animais; c no exame histopatológico, as diferenças encontradas entre grupos foram transitórias, não persistindo após 60 dias de pós-operatório. CONCLUSÃO: O polidioxanone mostrou ser a melhor opção, entre os dois fios, para sutura de artérias em crescimento, pois causa pouca ou nenhuma restrição ao crescimento arterial na linha de sutura, mesmo quando se emprega a técnica contínua.PURPOSE: To assess the arterial suture, comparing continuous and interrupted techniques, in abdominal aorta of growing rabbbits, using two types of suture material: Polypropylene 7-0 (nonabsorbable and Polydioxanone 7-0 (absorbable. METHODS: Groups: GI - Control, without arterial suture; GII - Polypropylene, Interrupted technique; GIII - Polipropilene, Continuous technique; GIV - Polydioxanone, Interrupted technique and GV - Polydioxanone, Continuous technique. Each group was subdivided in four Moments of Euthanasia , according with the number of days after surgery: 7 , 14 , 30 and 60 days. The following itens were assessed: weight, arterial diameters and pulse, stenosis, thrombosis, tissue adherence at the suture line, aortography, suture material visibility, suture line healling visibility and microscopic study. RESULTS: a after 60 days, the suture line site had a significant growing in all groups; b interrupted technique result less suture line stenosis in surgical act and in euthanasia c the difference between groups showed in the microscopic study, was transitory, not pesisting after 60 days post surgery; CONCLUSION: Polydioxanone is better than polypropylene for suture in growing artery, not causing (or causing little restriction to the growing of the suture line, even though using continuous technique.

  10. Sutura arterial com técnicas contínua e de pontos separados, utilizando-se os fios polipropilene e polidioxanone: estudo experimental em coelhos / Arterial suture with continuous and interrupted techniques, using polypropylene and polydioxanone threads: experimental study in rabbits

    Scientific Electronic Library Online (English)

    Nelson Leonardo Kerdahi Leite de, Campos; Anete Kinumi, Ueda; Marcos Augusto de, Moraes-Silva.

    2003-10-01

    Full Text Available OBJETIVO: Observar o comportamento da sutura arterial em aortas abdominais de coelhos em crescimento, comparando-se as técnicas contínua e com pontos separados, empregando-se dois tipos de fios: Polipropilene 7-0 (inabsorvível) e Polidioxanone 7-0 (absorvível). MÉTODOS: Grupos: GI - Controle (sem su [...] tura); GII - Polipropilene, Pontos Separados; GIII - Polipropilene, Contínua; GIV - Polidioxanone, Pontos Separados e GV - Polidioxanone, Contínua. Cada grupo foi subdividido em quatro Momentos de Eutanásia: aos 7, 14, 30 e 60 dias de pós-operatório. Foram avaliados: peso dos animais, diâmetros e pulsos arteriais, estenose, trombose, aderências, aortografia, visibilidade do fio, cicatrização e microscopia. RESULTADOS: a) após 60 dias, o local da linha de sutura cresceu de forma significativa em todos os grupos; b) a técnica de sutura com pontos separados causou menor estenose da linha de sutura, observada tanto no ato cirúrgico, como na eutanásia dos animais; c) no exame histopatológico, as diferenças encontradas entre grupos foram transitórias, não persistindo após 60 dias de pós-operatório. CONCLUSÃO: O polidioxanone mostrou ser a melhor opção, entre os dois fios, para sutura de artérias em crescimento, pois causa pouca ou nenhuma restrição ao crescimento arterial na linha de sutura, mesmo quando se emprega a técnica contínua. Abstract in english PURPOSE: To assess the arterial suture, comparing continuous and interrupted techniques, in abdominal aorta of growing rabbbits, using two types of suture material: Polypropylene 7-0 (nonabsorbable) and Polydioxanone 7-0 (absorbable). METHODS: Groups: GI - Control, without arterial suture; GII - Pol [...] ypropylene, Interrupted technique; GIII - Polipropilene, Continuous technique; GIV - Polydioxanone, Interrupted technique and GV - Polydioxanone, Continuous technique. Each group was subdivided in four Moments of Euthanasia , according with the number of days after surgery: 7 , 14 , 30 and 60 days. The following itens were assessed: weight, arterial diameters and pulse, stenosis, thrombosis, tissue adherence at the suture line, aortography, suture material visibility, suture line healling visibility and microscopic study. RESULTS: a) after 60 days, the suture line site had a significant growing in all groups; b) interrupted technique result less suture line stenosis in surgical act and in euthanasia c) the difference between groups showed in the microscopic study, was transitory, not pesisting after 60 days post surgery; CONCLUSION: Polydioxanone is better than polypropylene for suture in growing artery, not causing (or causing little) restriction to the growing of the suture line, even though using continuous technique.

  11. Comparison of scar with polypropylene and polyglactin 910 in thyroid incisions

    International Nuclear Information System (INIS)

    To compare quality of scar after subcuticular stitches between Polypropylene (Prolene), a non-absorbable suture, with Polyglactin 910 (Vicryl), an absorbable suture after thyroid surgery. Study Design: Randomized controlled trail (RCT). Place and Duration of Study: Department of Surgery Combined Military Hospital and Military Hospital Rawalpindi from 1 Jan 2007 to 31 Dec 2007. Material and Methods: Sixty patients undergoing elective thyroid surgery were included and randomly divided into two groups using random number tables. Informed written consent was obtained from each patient. The neck wound was closed by subcuticular suturing technique and the suture material was used according to the sampling technique. The patients were followed up in OPD on tenth post operative day and twelve weeks after surgery for the quality of scar. Results: After 10 days, 1 patient in each of the Polypropylene group (3.3%) and Polyglactin 910 group (3.3%) had a bad scar (p = 1.000). After twelve weeks of surgery, 2 patients in the Polypropylene group (6.7%) and 3 patients in the Polyglactin 910 group (10.0%) had bad scars (p = 1.000). Conclusion: There is no significant difference between the frequency of bad scar formation in the Polypropylene and Polyglactin 910 group. It is thus recommended that absorbable Polyglactin 910 sutures should be used for wound closure after thyroid surgery as it does not require suture removal and thus prevents patient anxiety and discomfort and also saves ent anxiety and discomfort and also saves surgeon and staff's time. (author)

  12. Gross and Histologic Evaluation of Abdominal Adhesions Associated with Chromic Catgut and Polypropylene Sutured Enteropexies in Dog / Evaluación Macroscópica e Histológica de las Adherencias Abdominales Asociadas a Enteropexias Suturadas con Catgut Crómico y Polipropileno en Perros

    Scientific Electronic Library Online (English)

    J. F, Akinrinmade; A. O, Lawal.

    1221-12-01

    Full Text Available Fueron evaluados los patrones macroscópicos e histológicos de las adherencias abdominales formadas por el uso de catgut crómico y materiales de sutura de polipropileno. Los exámenes macroscópicos e histológicos no revelaron diferencias significativas (p> 0,05) en el grado de adherencias observadas e [...] n los sitios de la enteropexia en ambos materiales de sutura. El uso de suturas de polipropileno con mejores cualidades debe ser considerado en lugar del catgut cromado para procedimientos en los que la adherencia en el perro es deseada. Abstract in english The gross and histologic patterns of abdominal adhesions formed by the use of chromic catgut and polypropylene suture materials were evaluated in dogs. Gross and histologic examinations did not reveal significant difference (p>0.05) in the degree of adhesions observed at enteropexy sites in both sut [...] ure materials. The use of polypropylene with superior suture qualities should be considered instead of chromic catgut for procedures in which adhesion is desired in the dog.

  13. Deterioration of polypropylene by radiation

    International Nuclear Information System (INIS)

    Radiation sterilization is not applied to the medical implement using polypropylene because of the severe deterioration by gamma ray irradiation. It has been reported that the chain reaction due to oxygen and peroxide radical contributes to the process of deterioration. The authors concluded that by the irradiation of electron beam, the sterilization of the surgical sutures made of polypropylene is feasible, and reported on the correlation of the lowering of the tensile strength by irradiation and the radical formed. However, the ESR spectra of the radical formed in the surgical sutures made of polypropylene irradiated with electron beam and gamma ray were different from the wave form of the peroxide radical of polypropylene reported before, accordingly, the identification was necessary. By this research, the above ESR spectra were proved by the anisotropy of g of peroxide radical, and the second radical other than the above peroxide radical was found. The experimental method and the results are reported. The research on the deterioration of polypropylene by radiation must be forwarded by examining both conventional peroxide radical P and ''S'' radical. (Kako, I.)

  14. Effect of suture material on platelet deposition onto prosthetic material

    International Nuclear Information System (INIS)

    Previous studies have demonstrated the importance of employing prosthetic material with minimal thrombogenicity. However, the role of different suture materials in early thrombotic events on prosthetic materials has not been examined. Experiments were designed to analyze the effects of suture on platelet graft interaction using an in vivo baboon hemocompatability screen. 111Indium labeled, autologous platelet deposition was determined on expanded polytetrafluoroethylene (ePTFE) containing suture lines of polypropylene (Prolene), polybutester (Novafil), and ePTFE (Gore-Tex). A significant increase in platelet deposition was noted not only at the suture line, but proximal and distal to it as well. The results were different for each of the sutures employed and suggest that the suture line may influence early platelet deposition in the perianastomotic region, not only at the suture line, but proximally and distally as well

  15. Electron beam sterilization surgical sutures, 2

    International Nuclear Information System (INIS)

    Possibility of electron beam (1.5 MeV, Van de Graaff accelerator) sterilization of a polypropylene surgical suture was examined from the points of sterilization effect and material degradation by the reason of that ? ray sterilization has not been permitted of its high degree of degradation. The D values of B. pumilus ATCC 27142 dry spores were determined to be 0.11 x 104 Gy in air and 0.18 x 104 Gy under the nitrogen stream irradiation, and the sterilization doses for electron beam were calculated to be 1.6 x 104 Gy in air and 2.7 x 104 Gy under the nitrogen stream, corresponding to ? ray sterilization assurance level of 2.5 x 104 Gy. Tensile strength of the polypropylene suture was 95 % of original strength soon after electron beam irradiation in air and was changed to be 81 % after 6 months storage, this is within the limit of the recommended value of 80 %. Furthermore, heat treatment (85 deg C, 1 hr.) following irradiation reduced degradation of irradiated polypropylene: its tensile strength was 93 % soon after irradiation but 97 % after 6 months. In the case of irradiation under the nitrogen stream, tensile strength after 6 months storage was 73 % without heat treatment, but 93 % with heat treatment. Based on the above results, we concluded that electron beam sterilization is applicable to the polypropylene surgical suture used in this experiment and heat treatment successive irradiation is effective to resccessive irradiation is effective to restrain material degradation. (author)

  16. Sterilization of surgical sutures by electron beam irradiation, (2)

    International Nuclear Information System (INIS)

    For polypropylene threads as surgical sutures as irradiated with electron beam and also with gamma ray for sterilization, the tensile strength, elongation and their variation in course of time, and also the influence of remaining radicals and the effect of heat treatment after irradiation were examined. The index fungus used was the spore of B. pumilus ATCC 27142, and electron beam irradiation was made with a linear accelerator. Gamma ray irradiation was made with cobalt-60. Besides such suture threads as silk, gut, etc., the sterilization of polypropylene sutures, which is impossible by gamma ray, is possible by electron beam irradiation. For polypropylene threads, the heat treatment after irradiation is practically useful. (Mori, K.)

  17. Tension of knotted surgical sutures shows tissue specific rapid loss in a rodent model

    OpenAIRE

    Klink Christian D; Binnebösel Marcel; Alizai Hamid P; Lambertz Andreas; vonTrotha Klaus T; Junker Elmar; Disselhorst-Klug Catherine; Neumann Ulf P; Klinge Uwe

    2011-01-01

    Abstract Background Every surgical suture compresses the enclosed tissue with a tension that depends from the knotting force and the resistance of the tissue. The aim of this study was to identify the dynamic change of applied suture tension with regard to the tissue specific cutting reaction. Methods In rabbits we placed single polypropylene sutures (3/0) in skin, muscle, liver, stomach and small intestine. Six measurements for each single organ were determined by tension sensors for 60 minu...

  18. [Ideal suture methods for skin, subcutaneous tissues and sternum].

    Science.gov (United States)

    Ogawa, Rei

    2012-04-01

    Non-absorbable sternal closure methods such as stainless steel wiring have been widely used, but biocompatibility and osteoconductivity of absorbable materials have advantages in acceleration of wound healing. Combined use of stainless steel wires with absorbable materials may contribute to minimizing sternal complications.Fascial tension reduction sutures, where the tension is placed on the layer of deep fascia and superficial fascia, are recommended for skin/subcutaneous closure. This means that the use of dermal sutures is minimized;indeed, dermal sutures can be avoided altogether if the wound edges can be joined naturally under very small tension. We prefer 0, 2-0 polydioxanone sutures (PDS II) for deep/superficial fascia sutures, 4-0 or 5-0 PDS II for dermal sutures (if they are necessary), and 6-0 or 7-0 polypropylene or nylon sutures (Proline or Ethilon) for superficial sutures. The consequence of such suturing is that the wound edges are elevated smoothly with minimal tension on the dermis that appears to prevent the development of large scars. PMID:22485038

  19. New-Fangled Slowly-Absorbable versus Non-Absorbable Sutures for Abdominal Fascial Closure. Have the Goals towards an Advantageous Suture Been Met?

    Directory of Open Access Journals (Sweden)

    Georgios Anthimidis

    2013-05-01

    Full Text Available Background-Aim: The technique of abdominal closure along with the material to be used is constantly evolving. The aim of the present study is to evaluate differences in midline laparotomy closure with a standard closure technique and new-fangled slow-absorbable versus non-absorbable sutures. Material and Methods: A prospective, comparative study of patients undergoing laparotomy closure with either STARDIOX (Polydioxanone or STARLENE (Polypropylene sutures during a 9 month period was performed. Patients were evaluated and compared in terms of surgical site infection, incisional hernia, burst abdomen, and suture sinus formation. Results: A total of 284 patients were included [141 in the STARDIOX (Polydioxanone group and 143 in the STARLENE (Polypropylene group]. Sinus formation was not noticed and no palpable knots were reported in both groups. Moreover burst abdomen was never encountered. Incisional hernia rates were similar for both suture materials: n = 6 (4.3% for the STARDIOX (Polydioxanone group and n = 5 (3.5% for the STARLENE (Polypropylene group. There was not statistically significant relationship between the type of suture that was used and wound infection: n = 5 (3.5% in the STARDIOX (Polydioxanone group and n = 6 (4.2% in the STARLENE (Polypropylene group. Complications did not occur in 96.1% of all patients. Conclusions: Our study suggests that there are no significant differences between these two new-fangled sutures. It seems that progress of suture materials has led to a step towards the goals of a beneficial suture and from then on complications of surgical wound closure should be merely a matter of operative technique.

  20. A comparison of ultrasonic suture welding and traditional knot tying.

    Science.gov (United States)

    Richmond, J C

    2001-01-01

    The slippage of knots and the technical challenge of tying them securely are potential impediments to certain arthroscopic procedures. Ultrasonic energy delivered at 70 kHz can be used to weld No. 2 polypropylene suture. This method was compared with a traditional knot (surgeon's knot with four alternating half hitches) tied with an open technique to determine whether welding of sutures is comparable, in mechanical properties, to hand-tied knots. Both loops were fashioned around a 0.25-inch mandrel and then tested. The load to reach 3-mm elongation (point of likely biologic failure of a repair) was significantly greater for welded sutures than for knots. The elongation at ultimate failure was significantly less for welded sutures than for knots. The number of cycles to failure and the creep after initial displacement were similar for both welded and knotted suture loops. The ultimate load to failure was significantly greater for the knotted than for the welded suture. The welding of suture for the repair of musculoskeletal soft tissue presents an attractive alternative to traditional knot tying, particularly for arthroscopic applications. PMID:11394598

  1. Suture midface suspension

    Directory of Open Access Journals (Sweden)

    Murthy Rachna

    2006-11-01

    Full Text Available Abstract Objective To describe a simple and effective facelift technique useful as an adjunct to other oculoplastic procedures Methods Retrospective, non-comparative case series. Thirty five patients undergoing suture midface suspension from 1998 to 2000. Suspension sutures were passed from the nasolabial fold to the temporalis fascia to elevate the midface and the corner of the mouth. Results A satisfactory and stable outcome is obtained in 2 years of follow up. Conclusion Suture midface suspension is a safe and effective technique for the management of midface descent.

  2. Trabeculectomy with releasable sutures.

    OpenAIRE

    Kolker, A. E.; Kass, M. A.; Rait, J. L.

    1993-01-01

    We attempted to reduce some of the postoperative complications of trabeculectomy by using releasable scleral flap sutures. This technique allows an initial tight closure of the scleral flap with the option to increase aqueous humor outflow in the early postoperative period. We reviewed our experience with trabeculectomy and releasable sutures in 146 eyes (134 patients) and compared these cases with a prior series of 128 eyes (124 patients) that underwent trabeculectomy with permanent scleral ...

  3. Short- and long-term biomechanical and morphological study of new suture types in abdominal wall closure.

    Science.gov (United States)

    Simón-Allué, R; Pérez-López, P; Sotomayor, S; Peña, E; Pascual, G; Bellón, J M; Calvo, B

    2014-09-01

    To perform an abdominal-wall closure, a continuous suture is the preferred method. The suture materials that are most commonly employed in abdominal surgery are polypropylene and polydioxanone. However, in recent times, new products have been marketed, such as non-absorbable polyurethane with elastic properties (Assuplus(®), Assut Europe, Italy) and absorbable barbed polydioxanone (Filbloc(®), Assut Europe, Italy). The purpose of this study was to compare the ability of those against the standard polypropylene (Surgipro(TM), Covidien, USA) and polydioxanone (Assufil(®), Assut Europe, Italy) to mimic the biomechanical behavior of the abdominal wall closure. Comparison of the sutures was made first with the materials alone and later in a laparotomy closure of a rabbit abdomen, used as an animal model. The biomechanical analysis consisted of uniaxial tensile tests of threads and sutured samples of the animal abdomen. In the latter case, results were analyzed at short- (21days) and long- (180days) term intervals after the surgery. The morphology studies and collagen expression of the samples were also investigated. The results determined that polydioxanone and polypropylene sutures showed a linear elastic behavior, with barbed polydioxanone as the most compliant suture and polyurethane as the stiffest. The sutured samples showed a statistically significant loss of resistance, measured as the load needed to perform a certain stretch, when compared with the corresponding control tissue. Analysis of the stress-stretch curves showed that elastic polyurethane was the only suture able to reproduce the mechanical behavior of healthy tissue in the short term, while the rest of the sutures remained less stiff. This coincides with the expression of type I collagen observed in this group at this point in the study. In the long term, there was no difference among the sutures, and none was able to mimic control behavior. PMID:24859461

  4. Selective suture cutting for control of astigmatism following cataract surgery

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    Bansal R

    1992-01-01

    Full Text Available Use of 10-0 monofilament nylon in ECCE cataract surgery leads to high with the rule astigmatism. Many intraoperative and post operative methods have been used to minimise post operative astigmatism. We did selective suture cutting in 38 consecutive patients. Mean keratometric astigmatism at three and six weeks post operative was 5.76 and 5.42 dioptres (D respectively. 77.5% of eyes had astigmatism above 2 D. Selective suture cutting along the axis of the plus high cylinder was done after six weeks of surgery. Mean post suture cutting keratometric astigmatism was 3.3 D and 70% of the eyes had astigmatism below 2 D. After 3 months of surgery mean keratometric astigmatism was reduced to 1.84 D. Axis of the astigmatism also changed following suture cutting. 40% of the eyes showed improvement in their Snellen acuity following reduction in the cylindrical power.

  5. Radiosterilization of surgical suture materials

    International Nuclear Information System (INIS)

    In addition to a historical survey, the paper deals with basic microbiological aspects of radiation sterilization, especially with regard to absorbable suture materials, and with the radiation effects on the physical, mechanical, chemical and biological properties of suture materials. Experimental and clinical experience with the application of radiosterilized suture materials is presented. The effects of irradiation on nonabsorbable suture materials, some materials for foil packaging and alcoholic preservative solutions are also discussed. (author)

  6. Releasable suture technique for trabeculectomy

    Directory of Open Access Journals (Sweden)

    Jacob Pushpa

    1993-01-01

    Full Text Available We studied the effect of the releasable suture technique on immediate postoperative intraocular pressure (IOP. Nine eyes of nine patients with glaucoma had trabeculectomy with a releasable suture. In the six eyes that did not receive antimitotics, the suture was released by the fifth postoperative day; in the others suture release was delayed up to the fourteenth day. Of the nine patients, one had an acceptable postoperative IOP and did not need suture release; in another the suture broke and could not be released. In the remaining seven patients, the difference between the pre-release and post-release IOP was statistically significant (p < 0.001. The complications of this technique include failed suture release, subconjunctival hematoma and a distinctive "windshield wiper" keratopathy.

  7. Comparative study of trabeculectomy using single sutures versus releasable sutures

    Science.gov (United States)

    Matlach, Juliane; Hoffmann, Niels; Freiberg, Florentina J; Grehn, Franz; Klink, Thomas

    2012-01-01

    Background The purpose of this study was to compare the outcomes of trabeculectomy using single sutures or releasable sutures. Methods This retrospective study analyzed the medical records of 61 patients who had undergone trabeculectomy using single sutures (n = 33, 54.1%) or releasable sutures (n = 28, 45.9%). The scleral flap was secured with a mean 3.9 (range 3–5) single sutures in 33 patients and with three releasable sutures in 28 patients. Primary outcomes were the success rate, based on intraocular pressure and medication usage, and the frequency of complications and post-surgical interventions. The criteria used to determine complete success were, first, intraocular pressure < 18 mmHg and, second, ?21 mmHg and ?20% intraocular pressure reduction without glaucoma medication. Results All patients had an intraocular pressure ? 21 mmHg; 87.5% in the single suture group and 92.6% in the releasable suture group had an intraocular pressure < 18 mmHg at 24 months. There was a highly significant reduction in intraocular pressure to baseline values in both groups at the last visit. Applying the first criterion, complete success was achieved in 57.6% of patients with single sutures and 71.4% with releasable sutures, and based on the second criterion, 66.7% and 71.4%, respectively. No significant difference was found between the groups with regard to intraocular pressure, or success or complication rates. Conclusion The results of trabeculectomy using single sutures or releasable sutures are equivalent. Therefore, the choice of suture technique should be based on individual patient requirements and surgeon experience. PMID:22848142

  8. First investigation of spider silk as a braided microsurgical suture.

    Science.gov (United States)

    Kuhbier, Joern W; Reimers, Kerstin; Kasper, Cornelia; Allmeling, Christina; Hillmer, Anja; Menger, Björn; Vogt, Peter M; Radtke, Christine

    2011-05-01

    Inhibition of axonal outgrowth accompanied by neuroma formation appears in microsurgical nerve repair as reaction to common microsuture materials like silk, nylon, or polyglycolic acid. In contrast, recent findings revealed advantages of spider silk fibers in guiding Schwann cells in nerve regeneration. Here, we asked if we could braid microsutures from native spider silk fibers. Microsutures braided of native spider dragline silk were manufactured, containing either 2 × 15 or 3 × 10 single fibres strands. Morphologic appearance was studied and tensile strength and stress-strain ratio (SSR) were calculated. The constructed spider silk sutures showed a median thickness of 25 ?m, matching the USP definition of 10-0. Maximum load and tensile strength for both spider silk microsutures were significantly more than 2-fold higher than for nylon suture; SSR was 1.5-fold higher. All values except elasticity were higher in 3 × 10 strand sutures compared to 2 × 15 strand sutures, but not significantly. In this pilot study, we demonstrate the successful manufacture of microsutures from spider silk. With regards to the mechanical properties, these sutures were superior to nylon sutures. As spider silk displays high biocompatibility in nerve regeneration, its usage in microsurgical nerve repair should be considered. PMID:21432995

  9. Suturas mecânicas Mechanic sutures

    Directory of Open Access Journals (Sweden)

    Alexandre Miranda Duarte

    2002-10-01

    Full Text Available The authors review the use of staplers in General Surgery, mainly in Gastroenterological Surgery highlighting safety and effectiveness. They emphasize that the mechanic anastomosis are a viable technique and in some conditions, the best way to perform the anastomosis. The use of staplers makes surgery faster and easier and complications are, generally related to surgeon's experience in using them. Although its costs are higher compared to handsewn suture, it can make the patient total cost lower.

  10. Radiation treatment of polypropylene

    International Nuclear Information System (INIS)

    Structural changes in polypropylene resulting from high energy electron beam irradiation have been examined. Polymer irradiated in a nitrogen atmosphere is characterized as containing long chain branch structures. A branching index, defined as the ratio of intrinsic viscosity of irradiated polymer to the intrinsic viscosity of linear polymer of equivalent molecular weight, is used to quantify the extent of branching. Polymer crystallization and solution properties undergo significant changes as a result of radiation treatment. Treated polypropylene is highly nucleated. Nucleation density is several orders of magnitude greater than linear polypropylene. Temperature rising elution fractionation (TREF) indicates that the long-chain branched structure contributes to increasing the solubility of polypropylene without greatly reducing the crystallizability and melting point of the solubilized fractions. The presence of long chain branching has a pronounced effect on the polymers extensional rheology in the molten state. Radiation treated polymer exhibits strain hardening elongational viscosity

  11. Ag??ZnO(10 0??????????

    Directory of Open Access Journals (Sweden)

    ???

    2014-08-01

    Full Text Available ???????????????????Ag??ZnO(10 0????????????????????Ag??ZnO(10 0?????????Ag??ZnO (10 0????????????????????ZnO(10 0???Ag??ZnO(10 0?????????????????Ag??ZnO(10 0?????????????Ag????????????????Ag??????????????????????????????????????????Ag??ZnO(10 0?????p???????p????????Ag??ZnO(10 0?????????????p????Based on the density function theory, we have performed first principles calculations of energetic stability and conductive properties and electronic structure of Ag incorporation on ZnO (10 0 surface, and after calculations, we have analyzed the relaxation of the structure and formation energy of Ag incorporation on ZnO (10 0 surface at different layers. Our results show that com-pared with pure ZnO (10 0, there is an obvious effect on the relaxation of the structure for Ag incorporation on ZnO (10 0 surface. Simultaneously, we found that the formation energy of the Ag incorporation on the first layer is the lowest in all cases. Therefore, Ag incorporation on the first layer is the most stable, which indicates that Ag atom prefers to collect in the surface layer instead of the bulk. And we found that the system for Ag incorporation on ZnO (10 0 surface demonstrates as p-type, which is in favors of fabricating p-type material. However, the ionization of Ag incorporation on ZnO (10 0 surface is much higher, which hinders the electronic ionize.

  12. Influence of suture regularity on corneal astigmatism after penetrating keratoplasty

    DEFF Research Database (Denmark)

    Hjortdal, Jesper; SØndergaard, Anders

    2011-01-01

    Abstract. Purpose: To investigate whether suture regularity affects corneal astigmatism after keratoplasty. Methods: Twenty-one patients undergoing penetrating keratoplasty for various corneal diseases were included in the study. The grafts were sutured in place using a single-running Nylon 10-0 suture, taking 24 bites. Immediately after surgery, standard calibrated images of the grafted eye were captured and stored. Using a dedicated image analysis programme, stitches and needle points were identified, and a number of suture regularity variables were calculated. Corneal topographic images were obtained before suture removal (12 months after surgery) and 3 months after suture removal (18 months after surgery). Topographic measures of astigmatism [surface regularity (SRI), surface asymmetry index (SAI) and simulated keratometric astigmatism] were calculated and correlated with the computed suture regularity variables. Results: The average stitch length was 3.04 +/- 0.28 mm and the distance between the outer needle points was 2.53 +/- 0.09 mm. The SRI was 1.26 +/- 0.36 and the SAI was 1.59 +/- 0.67 after 12 months; these decreased to 1.03 +/- 0.48 and 0.92 +/- 0.46 after 18 months, respectively. Corneal astigmatism was 6.38 +/- 2.99 and 5.87 +/- 3.13 dioptres after 12 and 18 months, respectively. Suture regularity did not affect SAI, SRI or corneal astigmatism significantly 12 months after surgery. Eighteen months after surgery (3 months after suture removal), the standard deviation on the original stitch length was found to significantly increase corneal astigmatism. In addition, the size of the counter-clockwise angle between stitch and graft radian was correlated significantly with a lower SRI. Conclusion: The origin of corneal astigmatism after penetrating keratoplasty is multifaceted. Regular stitch length and stitch advancement on the surface appears to improve the optical quality of the graft after suture removal. Factors such as stitch depth, suture tension and variations in wound construction might also beimportant predictors of corneal astigmatism after penetrating keratoplasty.

  13. Biodegradation of Polypropylene Nonwovens

    Science.gov (United States)

    Keene, Brandi Nechelle

    The primary aim of the current research is to document the biodegradation of polypropylene nonwovens and filament under composting environments. To accelerate the biodegradat ion, pre-treatments and additives were incorporated into polypropylene filaments and nonwovens. The initial phase (Chapter 2) of the project studied the biodegradation of untreated polypropylene with/without pro-oxidants in two types of composting systems. Normal composting, which involved incubation of samples in food waste, had little effect on the mechanical properties of additive-free spunbond nonwovens in to comparison prooxidant containing spunbond nonwovens which were affected significantly. Modified composting which includes the burial of samples with food and compressed air, the polypropylene spunbond nonwovens with/without pro-oxidants displayed an extreme loss in mechanical properties and cracking on the surface cracking. Because the untreated spunbond nonwovens did not completely decompose, the next phase of the project examined the pre-treatment of gamma-irradiation or thermal aging prior to composting. After exposure to gamma-irradiation and thermal aging, polypropylene is subjected to oxidative degradation in the presence of air and during storage after irradiat ion. Similar to photo-oxidation, the mechanism of gamma radiation and thermal oxidative degradation is fundamentally free radical in nature. In Chapter 3, the compostability of thermal aged spunbond polypropylene nonwovens with/without pro-oxidant additives. The FTIR spectrum confirmed oxidat ion of the polypropylene nonwovens with/without additives. Cracking on both the pro-oxidant and control spunbond nonwovens was showed by SEM imaging. Spunbond polypropylene nonwovens with/without pro-oxidants were also preirradiated by gamma rays followed by composting. Nonwovens with/without pro-oxidants were severely degraded by gamma-irradiation after up to 20 kGy exposure as explained in Chapter 4. Furthermore (Chapter 5), gamma-irradiated polypropylene nonwovens with pro-oxidants were invisible to the naked eye after 30 days of composting suggesting microbial attack was achieved. The final phase of the project encompasses the extrusion of bicomponent fibers. Because microorganisms desire to feed on hydrophilic molecules, commercially available starch-based polymers were spun with polypropylene resins in a sheath/core configuration. Similar to the previously discussed nonwovens studies, the bicomponent filaments were pretreated with heat (Chapter 6) and gamma-rays (Chapter 7) before evaluating the biodegradability under composting studies. The results from these chapters were reviewed to determine if bicomponent nonwovens under the same conditions could be manufactured.

  14. Lip suture with isobutyl cyanoacrylate.

    Science.gov (United States)

    de Blanco, L P

    1994-02-01

    Reported are two cases of dental trauma with lip lesions and a deep wound through the muscular structures. The aim of this paper was to show that using an easy method with isobutyl cyanoacrylate that suturing small to deep lip wounds can be achieved without conventional sutures that require more time, and possibly may cause cheloid healing. PMID:8005074

  15. Releasable suture technique for trabeculectomy

    Directory of Open Access Journals (Sweden)

    Thomas Ravi

    1997-01-01

    Full Text Available A retrospective review of 154 trabeculectomies with releasable sutures was performed to assess the effect of suture release on intraocular pressure (IOP at various postoperative periods. Release of the suture was necessary in 38% of cases. The immediate reduction in IOP was significant (p <0.01 when the suture was released during the first three postoperative weeks. Seventy percent of eyes had a reduction in IOP more than 5 mmHg if released within the first week compared to 20% after the third week. With suture release after the third postoperative week, there was no clinically significant decrease in IOP. The decrease in IOP was similar in eyes undergoing trabeculectomy alone or when cataract extraction through a separate corneal incision was undertaken simultaneously. The period during which release of suture was effective was not prolonged by use of antimetabolites. Complications included a typical windshield-wiper keratopathy (18 eyes, failure to release the suture (13 eyes, epithelial abrasion (6 eyes and a sub-conjunctival bleed (1 eye.

  16. Force sensing in surgical sutures:

    OpenAIRE

    Horeman, T.; Meijer, E. J.; Harlaar, J. J.; Lange, J. F.; Den Dobbelsteen, J. J.; Dankelman, J.

    2013-01-01

    The tension in a suture is an important factor in the process of wound healing. If there is too much tension in the suture, the blood flow is restricted and necrosis can occur. If the tension is too low, the incision opens up and cannot heal properly. The purpose of this paper is to describe the design and evaluation of the Stitch Force (SF) sensor and the Hook-In Force (HIF) sensor. These sensors were developed to measure the force on a tensioned suture inside a closed incision and to measur...

  17. Craniosynostosis of the lambdoid suture.

    Science.gov (United States)

    Rhodes, Jennifer L; Tye, Gary W; Fearon, Jeffrey A

    2014-08-01

    Craniosynostosis affecting the lambdoid suture is uncommon. The definition of lambdoid craniosynostosis solely applies to those cases demonstrating true suture obliteration, similar to other forms of craniosynostosis. In patients presenting with posterior plagiocephaly, true lambdoid craniosynostosis must be differentiated from the much more common positional molding. It can occur in a unilateral form, a bilateral form, or as part of a complex craniosynostosis. In children with craniofacial syndromes, synostosis of the lambdoid suture most often is seen within the context of a pansynostotic picture. Chiari malformations are commonly seen in multisutural and syndromic types of craniosynostosis that affect the lambdoid sutures. Posterior cranial vault remodeling is recommended to provide adequate intracranial volume to allow for brain growth and to normalize the skull shape. Although many techniques have been described for the correction of lambdoid synostosis, optimal outcomes may result from those techniques based on the concept of occipital advancement. PMID:25210507

  18. Advances in polypropylene based materials

    International Nuclear Information System (INIS)

    Polypropylene is an extremely versatile thermoplastic polymer known for its good performance/price ratio, excellent heat, moisture and chemical resistance, favorable processing characteristics and recyclability. Due to its universal properties, polypropylene is applied in numerous industrial fields such as electronic and electrical, automobile, textile, pipeline, etc. Furthermore, the progress in its synthesis and property modification in the last decade has contributed to the development of new polypropylene based materials with advanced performance. This review aims at reporting on some recent developments in polypropylene based materials, such as nano fibers, natural fiber reinforced composites, self-reinforced polypropylene and polypropylene/clay hybrids, that have replaced many types of engineering thermoplastics in high-performance applications. (Author)

  19. 21 CFR 878.5020 - Nonabsorbable polyamide surgical suture.

    Science.gov (United States)

    2010-04-01

    ...false Nonabsorbable polyamide surgical suture. 878.5020 Section 878...5020 Nonabsorbable polyamide surgical suture. (a) Identification. Nonabsorbable polyamide surgical suture is a nonabsorbable,...

  20. 21 CFR 878.5030 - Natural nonabsorbable silk surgical suture.

    Science.gov (United States)

    2010-04-01

    ... Natural nonabsorbable silk surgical suture. 878.5030 Section 878... Natural nonabsorbable silk surgical suture. (a) Identification. Natural nonabsorbable silk surgical suture is a nonabsorbable,...

  1. 21 CFR 878.5035 - Nonabsorbable expanded polytetrafluoroethylene surgical suture.

    Science.gov (United States)

    2010-04-01

    ...expanded polytetrafluoroethylene surgical suture. 878.5035 Section 878...expanded polytetrafluoroethylene surgical suture. (a) Identification. ...polytetrafluoroethylene (ePTFE) surgical suture is a monofilament,...

  2. 21 CFR 878.4840 - Absorbable polydioxanone surgical suture.

    Science.gov (United States)

    2010-04-01

    ...false Absorbable polydioxanone surgical suture. 878.4840 Section 878...4840 Absorbable polydioxanone surgical suture. (a) Identification. An absorbable polydioxanone surgical suture is an absorbable,...

  3. Sutured Floer homology and hypergraphs

    CERN Document Server

    Juhász, András; Rasmussen, Jacob

    2011-01-01

    By applying Seifert's algorithm to a special alternating diagram of a link L, one obtains a Seifert surface F of L. We show that the support of the sutured Floer homology of the sutured manifold complementary to F is affine isomorphic to the set of lattice points given as hypertrees in a certain hypergraph that is naturally associated to the diagram. This implies that the Floer groups in question are supported in a set of Spin^c structures that are the integer lattice points of a convex polytope. This property has an immediate extension to Seifert surfaces arising from homogeneous link diagrams (including all alternating and positive diagrams). In another direction, together with work in progress of the second author and others, our correspondence suggests a method for computing the "top" coefficients of the HOMFLY polynomial of a special alternating link from the sutured Floer homology of a Seifert surface complement for a certain dual link.

  4. Comparison of two techniques: interrupted mass closure and continuous mass closure with polypropylene in laparotomy

    International Nuclear Information System (INIS)

    Wound dehiscence is an acute wound failure. It commonly presents about one week after surgery and may be preceded by a serosanguinuous discharge. Wound dehiscence is an important cause of postoperative morbidity and mortality. To compare the early postoperative complications of closure of laparotomy wound by interrupted mass closure and continuous mass closure techniques. Sixty patients were included in this study and divided in two groups; group A and group B. Closure of laparotomy wound with monofilament polypropylene No.1 suture by interrupted mass closure technique for group A and continuous mass closure technique with same suture material in group B was done. In group A, 2 patients developed wound infection and 1 patient was found with wound dehiscence, while in group B, 3 patients suffered wound infection and 2 patients developed wound dehiscence. The closure of laparotomy wound by interrupted mass closure technique with polypropylene No.1 is better closure technique with low rate of wound infection and wound dehiscence as compared to continuous suturing technique with same suture material. (author)

  5. Torsion of monofilament and polyfilament sutures under tension decreases suture strength and increases risk of suture fracture.

    LENUS (Irish Health Repository)

    Hennessey, D B

    2012-08-01

    A continuous running suture is the preferential method for abdominal closure. In this technique the suture is secured with an initial knot and successive tissue bites are taken. At each tissue bite, the needle is rotated through the tissue; in doing so, the suture can twist around the knot which acts as an anchor.

  6. Unusual sutural bones at pterion

    OpenAIRE

    Nayak SB; Kv, S

    2008-01-01

    The existence of Wormian (sutural) bones in the skull is well known. We found three unusual Wormian bones at the right pterion in an adult Indian skull. The variation noted was unilateral. This type of variation has not been reported yet.

  7. Geometrically controlled tensile response of braided sutures.

    Science.gov (United States)

    Rawal, Amit; Sibal, Apurv; Saraswat, Harshvardhan; Kumar, Vijay

    2015-03-01

    Sutures are the materials used for wound closure that are caused by surgery or trauma. The main pre-requisite to the success of the suture is to obtain ultimate level of tensile properties with defined geometrical constraints. In this communication, the model for tensile properties of braided sutures has been proposed by elucidating the most important geometrical and material parameters. The model has accounted for the kinematical changes occurring in the braid and constituent strand geometries under defined level of strain. A comparison has been made between the theoretical and experimental results of stress-strain characteristics of braided sutures. PMID:25579946

  8. Influence of surgical sutures on wound healing

    Directory of Open Access Journals (Sweden)

    Mirkovi? Siniša

    2010-01-01

    Full Text Available Historical data on closing and suturing of surgical wounds describe a wide range of various suture materials. The choice of the surgical catgut, i.e. the type and diameter, depends on the locality, characteristics and condition of the tissue to be treated. From the standpoint of oral-surgical practice the following clinical parameters are of outstanding importance with respect to the selection of suture material: accumulation of soft deposits on the sutures, score of the adjacent soft tissues and dehiscence of the operative wound. Our prospective clinical study included 150 patients distributed into three groups of 50 subjects. The surgical procedure performed on each patient involved resection (apicotomy of the tooth root end in the intercanine sector of the upper jaw. The following suture materials were applied: Black Silc 5-0, Nylon 5-0 and Vicryl 5-0. The effects of the selected sutures were evaluated according to the wound dehiscence. The effects of the applied sutures were recorded on Days 2, 5 and 7 after the surgery. The comparison of cited parameters of the investigated materials after suturing the oral mucosa revealed that none of the used material was ideal; however, a certain advantage might be given to the synthetic monofilament suture materials.

  9. Radiation effect on stabilized polypropylene

    International Nuclear Information System (INIS)

    Radiation-induced oxidative degradation of stabilized polypropylene films using Co-60 ? irradiation at room temperature under different irradiation conditions (vacuum and oxygen) was investigated. Gas evolution, oxygen consumption, and mechanical properties were studied and analyzed quantitatively. The G values for the evolved gases during irradiation of stabilized polypropylene films under vacuum and in presence of oxygen are given. The stabilized polypropylene, irradiated at low doses under different conditions (air, oxygen, and vacuum), shows mechanical properties almost similar to those of the unirradiated one. However, at higher doses the mechanical properties were sharply decreased and deterioration was enhanced in the presence of oxygen due to the oxidative degradation. On the other hand, post-irradiation effect on the stabilized polypropylene irradiated up to 0.02 MGy under vacuum, was studied at various annealing temperatures and different storage time at room temperature. Molecular weight distribution curves for polypropylene samples irradiated in air atmosphere show that degradation of the high molecular weight chains is the predominant process in the range of irradiation doses under investigation. (author)

  10. Anastomose arterial com fio de polidioxanona e fio de polipropileno. Estudo comparativo em cães Arterial anastomose with polydioxanone and polypropilene suture. Comparative study in dogs

    Directory of Open Access Journals (Sweden)

    Eloísa de Brida Tormena

    2002-03-01

    Full Text Available Este estudo teve por objetivo comparar os efeitos do fio absorvível de polidioxanona com o fio inabsorvível de polipropileno, em anastomoses término-terminais, em artérias femorais de cães. Foram utilizados 20 cães, separados em dois grupos, para observação no 7º e no 30º dia de pós-operatório. Cada cão teve suas artérias femorais seccionadas e aproximadas em um lado com pontos separados de fio de polidioxanona 6-0, e no lado contralateral com o fio de polipropileno 6-0. A escolha do fio foi feita por sorteio, totalizando 40 anastomoses. Para análise estatística dos resultados aplicaram-se os testes de Fisher, Mac Nemar, Wilcoxon, Mann-Witney e o teste T de Student (a ? 0,05. Nas avaliações clínicas não foram observadas diferenças significantes entre os fios utilizados. Os resultados obtidos nas avaliações arteriográfica e macroscópica dos segmentos arteriais foram semelhantes, assim como na análise histológica morfológica. Na análise histológica morfométrica o fio de polipropileno apresentou número de células gigantes de corpo estranho significativamente maior que o fio de polidioxanona aos 7 e 30 dias de pós-operatório. Os resultados nos permitem concluir que, apesar da maior reação de corpo estranho observada com o fio de polipropileno, o fio de polidioxanona apresentou resultados semelhantes ao fio de polipropileno, em anastomoses arteriais em cães.The objetive of this study was to compare the effects of the absorbable polidioxanone suture to the nonabsorbable polypropylene suture, in end-to-end anastomoses, using dog’s femoral arteries. Twenty dogs were separated in two groups for observation on the 7th and 30th post-operatory day. Each dog had its femoral arteries seccioned and then aproximated one side with separate stitches of polidioxanone 6-0 suture, and the other side with polypropylene 6-0 suture. For the statistical studies Fisher, Mac nemar, Wilsoxon, Mann-Witney and T of Student tests (a ? 0,05 were carried out. No significant differences were observed between the sutures employed in clinical evolution. The results obtained in the arteriographic and macroscopic avaliation were similar, as well as the morphological histologic analysis. In the morfometric histologic analysis the polypropylene suture showed a significantly higher number of foreign body giant cells reaction, comparing to the polydioxanone suture on the 7th or 30th post-operatory day. The results allow us to conclude that, in spit of the higher reaction of foreign body observed with the polypropilene suture, the polydioxanone suture showed similar results in dog’s arterial anastomoses.

  11. Carbon dioxide laser-assisted nerve repair: effect of solder and suture material on nerve regeneration in rat sciatic nerve.

    Science.gov (United States)

    Menovsky, Tomas; Beek, Johan F

    2003-01-01

    In order to further improve and explore the role of lasers for nerve reconstruction, this study was designed to investigate regeneration of sharply transected peripheral nerves repaired with a CO(2) milliwatt laser in combination with three different suture materials and a bovine albumin protein solder as an adjunct to the welding process. Unilateral sciatic nerve repair was performed in 44 rats. In the laser group, nerves were gently apposed, and two stay sutures (10-0 nylon, 10-0 polyglycolic acid, or 25 microm stainless steel) were placed epi/perineurially. Thereafter, the repair site was fused at 100 mW with pulses of 1.0 s. In the subgroup of laser-assisted nerve repair (LANR), albumen was used as a soldering agent to further reinforce the repair site. The control group consisted of nerves repaired by conventional microsurgical suture repair (CMSR), using 4-6 10-0 nylon sutures. Evaluation was performed at 1 and 6 weeks after surgery, and included qualitative and semiquantitative light microscopy. LANR performed with a protein solder results in a good early peripheral nerve regeneration, with an optimal alignment of nerve fibers and minimal connective tissue proliferation at the repair site. All three suture materials produced a foreign body reaction; the least severe was with polyglycolic acid sutures. CMSR resulted in more pronounced foreign-body granulomas at the repair site, with more connective-tissue proliferation and axonal misalignment. Furthermore, axonal regeneration in the distal nerve segment was better in the laser groups. Based on these results, CO(2) laser-assisted nerve repair with soldering in combination with absorbable sutures has the potential of allowing healing to occur with the least foreign-body reaction at the repair site. Further experiments using this combination are in progress. PMID:12740882

  12. 21 CFR 878.4495 - Stainless steel suture.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 2010-04-01 false Stainless steel suture. 878.4495 Section 878.4495...Surgical Devices § 878.4495 Stainless steel suture. (a) Identification. A stainless steel suture is a needled or unneedled...

  13. 21 CFR 878.4930 - Suture retention device.

    Science.gov (United States)

    2010-04-01

    ...PLASTIC SURGERY DEVICES Surgical Devices § 878.4930 Suture retention device. (a) Identification. A suture retention device is a device...as a retention bridge, a surgical button, or a suture bolster, intended to...

  14. 21 CFR 882.4650 - Neurosurgical suture needle.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 false Neurosurgical suture needle. 882.4650 Section...NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4650 Neurosurgical suture needle. (a) Identification. A neurosurgical suture needle is a needle used...

  15. 21 CFR 878.4830 - Absorbable surgical gut suture.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 false Absorbable surgical gut suture. 878.4830 Section 878... § 878.4830 Absorbable surgical gut suture. (a) Identification...Controls Guidance Document: Surgical Sutures; Guidance for Industry...

  16. Surgical sutures: MR artifacts and sequence dependence.

    Science.gov (United States)

    Haramati, N; Penrod, B; Staron, R B; Barax, C N

    1994-01-01

    Artifact reduction is fundamental to the daily clinical application of magnetic resonance (MR) imaging. Imaging of the postoperative patient may be difficult because of surgically introduced materials that result in artifacts. The authors tested some commonly used types of surgical suture for MR susceptibility artifact with various imaging sequences. Ten different suture types were studied. Suture was immersed in vegetable oil in separate plastic test tubes. The sutures were also studied embedded in meat. All samples were studied with T1-weighted and T2-weighted spin-echo, STIR (short-inversion-time inversion-recovery), and two-dimensional and three-dimensional gradient-echo sequences. Silk suture produced the most artifact. PMID:8180462

  17. Mechanical similarities observed between polypropylene gels and molten polypropylenes

    Science.gov (United States)

    Oyer, A. J.; Carrillo, J.-M. Y.; Dobrynin, A. V.; Mackintosh, F. C.

    2013-03-01

    The gelation of syndiotactic and isotactic polypropylenes (sPP and iPP) was found when PPs were dissolved in 1,2,3,4-tetrahydronaphthalene (tetralin). Interestingly, it was found that the storage modulus of sPP-gel became higher than that of iPP-gel when PPs were dissolved in tetralin at low PP concentration (40 wt%).

  18. Preliminary stress/strain analysis of laser-soldered and -sutured vascular tissue

    Science.gov (United States)

    Ashton, Robert C., Jr.; Oz, Mehmet C.; Lontz, John F.; Lemole, Gerald M.

    1991-06-01

    Stress-strain profiles of welded tissue provide additional means of analysing and comparing laser soldering to alternative anastoinosing techniques. Three groups were created in a rabbit model: (1) nonincised control aortic tissue, (2) longitudinal aortotomies repaired with a 808 nm diodelaser (power density 4.8 watts/cm2) after topical application of fibrinogen mixed with indocyanine green dye (peak absorption 805 nm) , and (3) aortotomies repaired with 6-0 polypropylene suture in a running fashion. The rabbits were sacrificed on 0,l,7,and 28 postoperative days and the fresh aortic specimens were strained until disruption in order to produce a stress-strain profile graph. No significant differences were noted between sutured and bonded aorta at any time interval. Nonincised (which served as a control) aortic tissuewithstood significantly higher stress (plaser bonded anastoinoses are weaker than control aorta initially; however, after an early critical period, both treatments achieve the strength of control aorta. By one nionth post-operatively, sutured anastomoses have the disadvantage of creating a less distensible anastomosis.

  19. One stage adjustable sutures: practical aspects.

    OpenAIRE

    Ruben, S. T.; Elston, J. S.

    1992-01-01

    Strabismus surgery using one stage adjustable sutures was carried out under local anaesthesia in six patients with good results. The criteria for patient selection and the surgical technique are discussed.

  20. Chronic complaints after simple sutured repair for umbilical or epigastric hernias may be related to recurrence

    DEFF Research Database (Denmark)

    Westen, Mikkel; Christoffersen, Mette W

    2014-01-01

    PURPOSE: Umbilical and epigastric hernia repairs are minor, but are commonly conducted surgical procedures. Long-term results have only been sparsely investigated. Our objective was to investigate the risk of chronic complaints after a simple sutured repair for small umbilical and epigastric hernias. METHODS: A retrospective cohort study with a 5-year questionnaire and clinical follow-up was conducted. Patients undergoing primary elective, open non-mesh umbilical or epigastric sutured hernia repair were included. Patients completed a structured questionnaire regarding chronic complaints during work and leisure activities using a verbal rating scale. The primary outcome was chronic complaints. RESULTS: A total of 295 patients were included for analysis after a median of 5.0-year (range 2.8-8.0) follow-up period. Follow-up results were achieved from 262 of the included patients (90 % response rate). Up till 5.8 % of the patients reported moderate or severe pain and discomfort. Work and leisure activities wererestricted in 8.5 and 10.0 % of patients, respectively. Patients with chronic complaints had a higher incidence of recurrence (clinical and reoperation), than patients with none or mild complaints (78.6 vs. 22.2 % (P?suture (20.1 %) compared with non-absorbable suture repair (4.2 %) (P?sutured umbilical or epigastric repair was in the level of 5.5 % and could in part be explained by recurrence. Furthermore, absorbable suture should be omitted to reduce risk of recurrence.

  1. A Suture Model for Surgical Simulation

    OpenAIRE

    Lenoir, Julien; Meseure, Philippe; Grisoni, Laurent; Chaillou, Christophe

    2004-01-01

    In this paper, we propose a surgical thread model in order for surgeons to practice a suturing task. We first model the thread as a spline animated by continuous mechanics. The suture is simulated via socalled "sliding point" constraints, which allow the spline to move freely while constrained to pass through specific piercing points. The direction of the spline at these points can also be imposed. Moreover, to enhance realism, an adapted model of friction is proposed, which allows the thread...

  2. Review of the sterilization of surgical sutures

    International Nuclear Information System (INIS)

    The sterilization of surgical sutures by ionizing radiation was the first commercial application of this process to the sterilizing of medical products. The history of the sterilization of sutures goes back 100 years to Lord Lister and the developments parallel those of other medical reports. The evolution of such products is the result of ever improving technology in microbiological techniques, evaluation of physical properties. (author)

  3. Fracture Toughness Studies of Polypropylene- Clay Nanocomposites and Glass Fibre Reinfoerced Polypropylene Composites

    OpenAIRE

    A Ramsaroop; K. Kanny; T. P. Mohan

    2010-01-01

    In this paper, a comparative study on the fracture toughness of woven glass fibre reinforced polypropylene, chopped glass fibre reinforced polypropylene and nanoclay filled polypropylene composites is presented. Nanoclays (Cloisite 15A) of 1 wt. % to 5 wt. % were filled in polypropylene (PP) matrix and they were subjected to fracture toughness stu-dies. The specimen with 5 wt. % nanoclay showed 1.75 times and 3 times improvement in critical stress intensity factor (KIC) and strain energy rele...

  4. Massive obstetric haemorrhage following removal of a cervical suture

    OpenAIRE

    Howarth, Louise Ann; Sherliker, Sarah

    2011-01-01

    The authors present an unusual case of massive ante partum haemorrhage following removal of a cervical suture. This patient was admitted for routine removal of a McDonald’s cervical suture at 37 weeks gestation. The suture was densely adherent and after removal she suffered a haemorrhage of 2500 ml from where the suture was removed which led to fetal distress and an emergency caesarean section. The cervix was sutured and a vaginal pack inserted. During the procedure she developed hypovolaem...

  5. Woodflour as Reinforcement of Polypropylene

    Directory of Open Access Journals (Sweden)

    José Cláudio Caraschi

    2002-10-01

    Full Text Available The effect of the filler content and size, as well as accelerated aging on the mechanical properties of polypropylene composites reinforced with woodflour (WF/PP were evaluated. The composites were prepared by the extrusion of polypropylene with woodflour (Pinus elliotti based on following ratios: 15, 25 and 40 wt% with two different granulometries. The specimens were injection molded according to ASTM standards. The composite properties did not show significant differences as a function of the filler granulometry. We also observed that by increasing the filler content, both the mechanical properties and the melt flow index (MFI decreased, and the elasticity modulus, hardness and density increased. Concerning the accelerated aging, the composite presented a reduction in tensile properties. The results showed that the composite properties are extremely favorable when compared to other commercial systems reinforced by inorganic fillers.

  6. 21 CFR 878.5000 - Nonabsorbable poly(ethylene terephthalate) surgical suture.

    Science.gov (United States)

    2010-04-01

    ...poly(ethylene terephthalate) surgical suture. 878.5000 Section 878...poly(ethylene terephthalate) surgical suture. (a) Identification. ...poly(ethylene terephthalate) surgical suture is a multifilament,...

  7. Mechanical performance of gamma irradiated surgical sutures

    International Nuclear Information System (INIS)

    Surgical sutures are medical devices made of natural or synthetic polymeric materials that, due to its end-use, have to be sterilized. Historically, the sterilization by heat or using ethylene oxide had presented so numerous drawbacks that today the non-pollutant radiation sterilization has become a well established sterilization process, that brings, environmental, technical, and economical advantages. The amount of irradiation doses required for sterilization of health care products is 25 kGy in most instances to achieve the necessary sterility assurance level. As high energy radiation produces modifications in the molecular structure of organic materials with changes in its mechanical properties, the aim of this work was to evaluate the mechanical behavior of surgical sutures under irradiation. Silk, polyamide and catgut sutures were gamma irradiated up to doses of 50 kGy in an industrial irradiation sterilization plant. Afterwards, these sutures were mechanical tested for tensile strength under knot following the specifications of the NBR13904 draft standard, using the CTRD-INSTRON at IPEN. The mechanical lab results show that sutures made of Silk and Polyamide do not present any change in their mechanical performance up to the dose of 50 kGy. On the other hand, Catgut present mechanical stability up to 30 kGy and afterwards, a slight decrease in its tensile strength was detected. (author)

  8. Mechanical performance of gamma irradiated surgical sutures

    Energy Technology Data Exchange (ETDEWEB)

    Pino, Eddy S.; Rela, Paulo P. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

    2000-07-01

    Surgical sutures are medical devices made of natural or synthetic polymeric materials that, due to its end-use, have to be sterilized. Historically, the sterilization by heat or using ethylene oxide had presented so numerous drawbacks that today the non-pollutant radiation sterilization has become a well established sterilization process, that brings, environmental, technical, and economical advantages. The amount of irradiation doses required for sterilization of health care products is 25 kGy in most instances to achieve the necessary sterility assurance level. As high energy radiation produces modifications in the molecular structure of organic materials with changes in its mechanical properties, the aim of this work was to evaluate the mechanical behavior of surgical sutures under irradiation. Silk, polyamide and catgut sutures were gamma irradiated up to doses of 50 kGy in an industrial irradiation sterilization plant. Afterwards, these sutures were mechanical tested for tensile strength under knot following the specifications of the NBR13904 draft standard, using the CTRD-INSTRON at IPEN. The mechanical lab results show that sutures made of Silk and Polyamide do not present any change in their mechanical performance up to the dose of 50 kGy. On the other hand, Catgut present mechanical stability up to 30 kGy and afterwards, a slight decrease in its tensile strength was detected. (author)

  9. Welded polypropylene liners for large descaling tanks

    Science.gov (United States)

    Abel, H. P.

    1971-01-01

    Liners for nitric and hydrofluoric acid tanks show no sign of deterioration after 18 months of continuous use. Each side of each edge of the polypropylene sheets is chamfered, and sheets are welded from both sides with polypropylene filler rod and a special hot-air welding torch.

  10. Laparoscopic fascial suture repair of parastomal hernia.

    Science.gov (United States)

    Zia, Khawaja; McGowan, David Ross; Moore, Etienne

    2013-01-01

    Parastomal hernia is a recognised complication following stoma formation, representing a challenging problem to surgeons. At least three approaches for parastomal hernia repair have been described: fascial suture repair, relocation of stoma and local repair with use of mesh. In simple fascial suture repair only open techniques have been described. Relocation of stoma can be complicated with another parastomal hernia at the new site and risk of incisional hernia at the site of previous stoma. Mesh repair can be either open or laparoscopic. The recurrence rate and complications of parastomal hernia repair remain very high. We have invented a simple fascial suture laparoscopic repair of parastomal hernia with the use of the Crochet hook needle (EndoClose). This new technique may result in reduced pain, earlier discharge from hospital and reduced risk of infection as there is no mesh used as well as reduced risk of seroma formation. PMID:23780775

  11. Acute Airway Obstruction from a Suture Granuloma

    Directory of Open Access Journals (Sweden)

    Jawad Khan

    2010-03-01

    Full Text Available The complications of tracheotomy are routinely categorized from the time of operation to the onset of the complication and are thus divided into intraoperative, early, and late postoperative. A very common late complication is the development of granulation tissue. We describe a case of granulation tissue that formed around a retained silk suture obscuring about 40% of the lumen at exhalation and about 80% of the lumen with inspiration. The patient clinically experienced stridor, poor exercise tolerance, and difficulty in clearing tracheobronchial secretions. As a result, the patient required CO2 laser excision of the suture granuloma using a rigid ventilating bronchoscope and removal of the suture. We present an unusual but serious case of progressive airway obstruction.

  12. Patellar tendon repair with suture anchors using a combined suture technique of a Krackow-Bunnell weave.

    Science.gov (United States)

    Gaines, Robert J; Grabill, Scott E; DeMaio, Marlene; Carr, Donald

    2009-01-01

    Suture repair of the ruptured patellar tendon is the treatment of choice for patients requiring operative management. This standard technique includes fixation through transosseous tunnels in the patella. The use of suture anchor fixation has several advantages over the standard approach, including less dissection, decreased surgical time, more accurate suture placement, and a low-profile construct. Additionally, the pullout strength of suture anchors warrants consideration of this technique in these repairs. This article describes using suture anchors for repair of the acute ruptured patellar tendon with a combination of Krackow and Bunnell sutures. PMID:19104306

  13. Argon plasma irradiation of polypropylene.

    Czech Academy of Sciences Publication Activity Database

    Slepi?ka, P.; Vasina, A.; Kolská, Z.; Luxbacher, T.; Malinský, Petr; Macková, Anna; Švor?ík, V.

    2010-01-01

    Ro?. 268, 11-12 (2010), s. 2111-2114. ISSN 0168-583X. [19th International conference on Ion beam analysis. Cambridge, 07.09.2009-11.09.2009] R&D Projects: GA ?R GA106/09/0125; GA MŠk(CZ) LC06041; GA AV ?R(CZ) KAN400480701 Institutional research plan: CEZ:AV0Z10480505 Keywords : Polypropylene * Plasma treatment * RBS Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.042, year: 2010

  14. Optimal Suturing Technique and Number of Sutures for Surgical Implantation of Acoustic Transmitters in Juvenile Salmonids

    Energy Technology Data Exchange (ETDEWEB)

    Deters, Katherine A.; Brown, Richard S.; Boyd, James W.; Eppard, M. B.; Seaburg, Adam

    2012-01-02

    The size reduction of acoustic transmitters has led to a reduction in the length of incision needed to implant a transmitter. Smaller suture knot profiles and fewer sutures may be adequate for closing an incision used to surgically implant an acoustic microtransmitter. As a result, faster surgery times and reduced tissue trauma could lead to increased survival and decreased infection for implanted fish. The objective of this study was to assess the effects of five suturing techniques on mortality, tag and suture retention, incision openness, ulceration, and redness in juvenile Chinook salmon Oncorhynchus tshawytscha implanted with acoustic microtransmitters. Suturing was performed by three surgeons, and study fish were held at two water temperatures (12°C and 17°C). Mortality was low and tag retention was high for all treatments on all examination days (7, 14, 21, and 28 days post-surgery). Because there was surgeon variation in suture retention among treatments, further analyses included only the one surgeon who received feedback training in all suturing techniques. Incision openness and tissue redness did not differ among treatments. The only difference observed among treatments was in tissue ulceration. Incisions closed with a horizontal mattress pattern had more ulceration than other treatments among fish held for 28 days at 17°C. Results from this study suggest that one simple interrupted 1 × 1 × 1 × 1 suture is adequate for closing incisions on fish under most circumstances. However, in dynamic environments, two simple interrupted 1 × 1 × 1 × 1 sutures should provide adequate incision closure. Reducing bias in survival and behavior tagging studies is important when making comparisons to the migrating salmon population. Therefore, by minimizing the effects of tagging on juvenile salmon (reduced tissue trauma and reduced surgery time), researchers can more accurately estimate survival and behavior.

  15. Prolene monofilament suture in Boston Keratoprosthesis surgery

    Science.gov (United States)

    Kyrillos,, Ralph; Harissi-Dagher, Mona

    2011-01-01

    Summary Toxic reaction to nylon following uncomplicated cataract surgery and vitrectomy has been documented in the literature. We report the case of an aniridic patient with a known adverse reaction to nylon in whom Prolene suture was used in Boston Keratoprosthesis type 1 (KPro) surgery. During follow-up the cornea was checked for signs of inflammation and toxic reaction; at last follow-up (18 months) the patient showed no signs of complications due to Prolene. Our study suggests that Prolene suture may be used as an alternative to nylon in Boston KPro surgery in patients with a history of nylon toxicity. PMID:23362386

  16. Sutures versus staples in skin flap operations.

    OpenAIRE

    Coupland, R. M.

    1986-01-01

    Apposition of skin edges in plastic surgical procedures can be achieved by sutures or stainless steel staples. This retrospective study reviews 45 skin falp operations and finds that 20.6% of sutured flaps are complicated by partial necrosis or slow healing. These complications occur in 62.5% of stapled flaps. It is proposed that crimping of the skin edges by the staples results in tension across the flap. This mechanism is demonstrated on cadaver skin. The efficacy of staples in closure of s...

  17. Nanostructured medical sutures with antibacterial properties.

    Science.gov (United States)

    Serrano, Cristina; García-Fernández, Luis; Fernández-Blázquez, Juan Pedro; Barbeck, Mike; Ghanaati, Shahram; Unger, Ron; Kirkpatrick, James; Arzt, Eduard; Funk, Lutz; Turón, Pau; del Campo, Aránzazu

    2015-06-01

    Bacterial repellence in suture materials is a desirable property that can potentially improve the healing process by preventing infection. We describe a method for generating nanostructures at the surface of commercial sutures of different composition, and their potential for preventing biofilm formation. We show how bacteria attachment is altered in the presence of nanosized topographies and identify optimum designs for preventing it without compromising biocompatibility and applicability in terms of nanostructure robustness or tissue friction. These studies open new possibilities for flexible and cost-effective realization of topography-based antibacterial coatings for absorbable biomedical textiles. PMID:25818435

  18. The history and evolution of sutures in pelvic surgery

    OpenAIRE

    Muffly, Tyler M.; Tizzano, Anthony P.; Walters, Mark D.

    2011-01-01

    The purpose of the study is to review the history and innovations of sutures used in pelvic surgery. Based on a review of the literature using electronic- and hand-searched databases we identified appropriate articles and gynaecology surgical textbooks regarding suture for wound closure. The first documented uses of suture are explored and then the article focuses on the use of knotted materials in pelvic surgery. The development of suture of natural materials is followed chronologically unti...

  19. Electrospun Drug-Eluting Sutures for Local Anesthesia

    OpenAIRE

    Weldon, Christopher B.; Tsui, Jonathan H.; Shankarappa, Sahadev A.; Nguyen, Vy T.; Ma, Minglin; Anderson, Daniel G.; Kohane, Daniel S.

    2012-01-01

    We have developed a local anesthetic-eluting suture system which would combine the function and ubiquity of the suture for surgical repair with the controlled release properties of a biodegradable polymeric matrix. Drug-free and drug-loaded poly(lactic-co-glycolic acid) (PLGA) sutures were fabricated by electrospinning, with or without the local anesthetic bupivacaine. The tensile strength of the electrospun sutures decreased as drug content increased, but strains remained relatively similar ...

  20. Bidirectional Barbed Sutures for Wound Closure: Evolution and Applications

    OpenAIRE

    Paul, Malcolm D.

    2009-01-01

    Traditionally, wound closure sutures have in common the need to tie knots with the inherent risk of extrusion, palpability, microinfarcts, breakage, and slippage. Bidirectional barbed sutures have barbs arrayed in a helical fashion in opposing directions on either side of an unbarbed midsegment. This suture is inserted at the midpoint of a wound and pulled through till resistance is encountered from the opposing barbs; each half of the suture is then advanced to the lateral ends of the wound....

  1. Comparison of suture types in the closure of scalp wounds.

    LENUS (Irish Health Repository)

    Bonham, Joseph

    2011-06-01

    Innovation in practice can benefit patients and healthcare providers but must be evidence based. This article describes a quantitative study of whether absorbable sutures are as beneficial as non-absorbable sutures in the management of simple scalp lacerations in adults. The results suggest that absorbable sutures can provide the same cosmetic and functional results as non-absorbable sutures. Their use can also reduce patient returns and save money and resources.

  2. Natural Nanotubes Reinforcing Heterophasic Polypropylene

    Scientific Electronic Library Online (English)

    Suellem Barbosa, Cordeiro; Maria de Fátima Vieira, Marques.

    2015-04-01

    Full Text Available Nanocomposites of high-impact polypropylene resin and organosilane-functionalized nanotubes in halloysite clay were prepared with the introduction of peroxide to promote selective incorporation of the filler into the polypropylene phase of the matrix, with minor insertion into the EPR elastomeric ph [...] ase, thus improving the stiffness while preserving the high toughness of the material. Silica composites were also prepared as standard filler. The effect of increasing load content on the morphological and mechanical properties of this material was evaluated by SEM and DMA. The content of the hexane-extracted fraction of these composites after processing was evaluated. Halloysite was well-dispersed in the matrix. Composites with 10% of filler and 0.5% w/w of dicumyl peroxide had increased stiffness and higher loss factor. An increase of the E’ was generated by halloysite addition, but there was a higher decrease in Tan delta. Studies using experimental planning as a tool enabled choosing appropriate amounts of DCP to obtain a high performance composite.

  3. The contact invariant in sutured Floer homology

    OpenAIRE

    Honda, Ko; Kazez, William H; Matic, Gordana

    2007-01-01

    We describe an invariant of a contact 3-manifold with convex boundary as an element of Juh\\'asz's sutured Floer homology. Our invariant generalizes the contact invariant in Heegaard Floer homology in the closed case, due to Ozsv\\'ath and Szab\\'o. This version has some clarifications and new figures.

  4. Influence of the elastomeric polypropylene addition on the properties of commercial metallocenic polypropylene

    OpenAIRE

    Maria de Fátima V. Marques; Mariana Poloponsky; Érica Gervasoni Chaves

    2001-01-01

    Polypropylene with special properties can be obtained by metallocenic catalysts. These catalytic systems represent the beginning of a new age in polyolefins technology. In this work, the influence of the addition of a syndiotactic polypropylene (s-PP) on the processability and mechanical properties of a commercial isotactic polypropylene (i-PP) obtained by metallocenic catalysts was evaluated. Increasing addition of s-PP promoted better processability, with an increase in the impact strength ...

  5. Transfascial suture in laparoscopic ventral hernia repair; friend or foe?

    Science.gov (United States)

    Sahu, Diwakar; Das, Somak; Wani, Majid Rasool; Reddy, Prasanna Kumar

    2015-01-01

    'Suture hernia' is fairly a new and rare type of ventral hernia. It occurs at the site of transfascial suture, following laparoscopic ventral hernia repair (LVHR). Employment of transfascial sutures in LVHR is still debatable in contrast to tackers. Prevention of mesh migration and significant post-operative pain are the pros and cons with the use of transfascial sutures, respectively. We report an unusual case of suture hernia or transfascial hernia, which can further intensify this dispute, but at the same time will provide insight for future consensus. PMID:25883460

  6. Do Absorbable Sutures Exacerbate Presternal Scarring?

    OpenAIRE

    Durkaya, Suat; Kaptanoglu, Melih; Nadir, Aydin; Yilmaz, Sarper; Cinar, Ziynet; Dogan, Kasim

    2005-01-01

    We investigated cosmetic outcomes of the midline sternotomy incision. A randomized clinical trial was conducted in 60 patients who underwent surgery through a midline sternotomy incision. Patients were divided into groups A (n=30) and B (n=30). In addition, the incision line was also divided into 2 regions (upper and lower halves) in each group. In group A, the upper half of the skin was closed with absorbable 4-0 braided polyglycolic acid sutures (Sentesor®, Boz; Ankara, Turkey), and the lo...

  7. Acute Airway Obstruction from a Suture Granuloma

    OpenAIRE

    Jawad Khan; Razi Jafri; Maher Abu-Hamdan

    2010-01-01

    The complications of tracheotomy are routinely categorized from the time of operation to the onset of the complication and are thus divided into intraoperative, early, and late postoperative. A very common late complication is the development of granulation tissue. We describe a case of granulation tissue that formed around a retained silk suture obscuring about 40% of the lumen at exhalation and about 80% of the lumen with inspiration. The patient clinically experienced stridor, poor exercis...

  8. Sutural simplification in Physodoceratinae (Aspidoceratidae, Ammonitina

    Directory of Open Access Journals (Sweden)

    Checa, A.

    1987-08-01

    Full Text Available The estructural analysis of the shell septum interrelationship in sorne Jurassic ammonites allows us to conclude that sutural simplifications occurred throughout the phylogeny, were originated by alterations in the external morphology of the shell. In the case of Physodoceratinae the simplification observed in the morphology of the septal suture may have a double origin. First, an increase in the size of periumbilical tubercles may determine a shallowing of sutural elements and a shortening of saddle and lobe frilling. In other cases, shallowing is determined by a decrease in the whorl expansion rate, an apparent shortening of secondary branching not being observed.El análisis estructural de la interrelación concha-septo en algunos ammonites del Jurásico superior lleva a concluir que las simplificaciones suturales aparecidas a lo largo de la filogenia fueron originadas por alteraciones ocurridas en la morfología externa de la concha. En el caso concreto de la subfamilia Physodoceratinae, la simplificación observada en la morfología de la sutura puede tener un doble origen. En primer lugar, un incremento en el tamaño de los tubérculos periumbilicales puede determinar una pérdida de profundidad de los elementos de la sutura. siempre acompañada de una disminución en las indentaciones (frilling de sillas y lóbulos. En otros casos el acortamiento en profundidad está determinado por una disminución de la tasa de expansión de la espira, sin que se observe un acortamiento aparente de las ramificaciones secundarias.

  9. Automatic Detection of Wild-type Mouse Cranial Sutures

    DEFF Research Database (Denmark)

    Ólafsdóttir, Hildur; Darvann, Tron Andre

    In the study of craniofacial malformations, the cranial sutures are often of interest. The premature fusion of sutures occurring in e.g. Crouzon and Apert syndrome can lead to asymmetric head shape, enlarged intracranial pressure and blindness. In large population studies of such syndromes, automatic detection of the cranial sutures becomes important. We have previously built a craniofacial, wild-type mouse atlas from a set of 10 Micro CT scans using a B-spline-based nonrigid registration method by Rueckert et al. Subsequently, all volumes were registered nonrigidly to the atlas. Using these transformations, any annotation on the atlas can automatically be transformed back to all cases. For this study, two rounds of tracing seven of the cranial sutures, were performed on the atlas by one observer. The average of the two rounds was automatically propagated to all the cases. For validation, the observer traced the sutures on each of the mouse volumes as well. The observer outperforms the automatic approach by approximately 0.1 mm. All mice have similar errors while the suture error plots reveal that suture 1 and 2 are cumbersome, both for the observer and the automatic approach. These sutures can be hard to detect with the eye. We still believe that overall, the errors are not considerable and by qualitatively estimating the accuracy, the automatic sutures are very close to the observer sutures. Our plan is to improve the results by local feature detection methods.

  10. Twist is required for establishment of the mouse coronal suture.

    Science.gov (United States)

    Yoshida, Toshiyuki; Phylactou, Leonidas A; Uney, James B; Ishikawa, Isao; Eto, Kazuhiro; Iseki, Sachiko

    2005-05-01

    Cranial sutures are the growth centres of the skull, enabling expansion of the skull to accommodate rapid growth of the brain. Haploinsufficiency of the human TWIST gene function causes the craniosynostosis syndrome, Saethre-Chotzen syndrome (SCS), in which premature fusion of the coronal suture is a characteristic feature. Previous studies have indicated that Twist is expressed in the coronal suture during development, and therefore that it may play an important role in development and maintenance of the suture. The Twist-null mouse is lethal before the onset of osteogenesis, and the heterozygote exhibits coronal suture synostosis postnatally. In this study we investigated the function of Twist in the development of the mouse coronal suture, by inhibiting Twist synthesis using morpholino antisense oligonucleotides in calvarial organ culture. Decreased Twist production resulted in a narrow sutural space and fusion of bone domains within 48 h after the addition of the morpholino oligonucleotides. Proliferation activity in the sutural cells was decreased, and the expression of osteogenic marker genes such as Runx2 and Fgfr2 was up-regulated in the developing bone domain within 4 h. These results suggest that during establishment of the suture area, Twist is required for the regulation of sutural cell proliferation and osteoblast differentiation. PMID:15857364

  11. U10.0 Undulator conceptual design report

    International Nuclear Information System (INIS)

    The U10.0 Undulator described here is a 43 period, 10 cm period, 4.5 meter long insertion device. Designed for the Advanced Light Source (ALS) storage ring at the Lawrence Berkeley Laboratory. This insertion device will provide high brightness, quasi-monochromatic radiation in the 5-950 eV energy range. This conceptual design report includes sections on: parameter development, spectral performance, and accelerator requirements, physics specifications and the detailed conceptual design of the magnetic structure, the support/drive systems, the insertion device control system, the vacuum system, and installation for the U10.0 Undulator

  12. Mobility as a mechanism for radiation stabilization of polypropylene

    International Nuclear Information System (INIS)

    Termination rates of radiation induced primary alkyl radicals are studied with ESR in polypropylene formulations containing additives that increase main chain mobility. The incorporation of mobilizing additives into polypropylene significantly improves radiation induced mechanical property degradation. (author)

  13. The complication and management of suturing femoral arteries with suture mediated closure system

    International Nuclear Information System (INIS)

    Objective: To discuss the femoral vascular complications and management in the patients with coronary angiography (CAG) and percutaneous coronary intervention (PCI) after applying the Suture Mediated Closure System (SMCS). Methods: The authors observed the successful rate and the vascular complications in patients treated with the SMCS. Results: Two hundreds and eighteen patients were treated with the SMCS, obtaining the success rate of 91.3%. Complication involved only one hematoma with femoral arterial infection (0.5%), but no pseudoaneurysm, no embolus formation and embolization. Conclusions: The suture closure system used in coronary angiography and PCI has high successful rate and less vascular complications. (authors)

  14. The frontosphenoidal suture: fetal development and phenotype of its synostosis

    International Nuclear Information System (INIS)

    Isolated synostosis of the frontosphenoidal suture is very rare and difficult to diagnose. Little has been reported on the clinical presentation and fetal development of this suture. To understand the development of the frontosphenoidal suture and the outcome of its synostosis. We studied the normal fetal development of the frontosphenoidal suture in dry human skulls and the clinical features of four patients with isolated synostosis of the frontosphenoidal suture. The frontosphenoidal suture develops relatively late during the second trimester of pregnancy, which explains the mild phenotype when there is synostosis. This rare craniosynostosis results in a deformity that causes recession of the lateral part of the frontal bone and supraorbital rim, with minimal facial asymmetry. Three-dimensional CT is the best examination to confirm the diagnosis. Isolated frontosphenoidal synostosis should be considered in patients with unilateral flattening of the forehead at birth that does not improve within the first few months of life. (orig.)

  15. A technique for introducing looped sutures in flexor tendon repair

    Directory of Open Access Journals (Sweden)

    Kamath B

    2006-01-01

    Full Text Available Stronger flexor tendon repairs facilitate early active motion therapy protocols. Core sutures using looped suture material provide 1 ½ to twice the strength of Kessler?s technique (with four strand and six strand Tsuge technique respectively. The technique is well-described and uses preformed looped sutures (supramid. This is not available in many countries and we describe a technique whereby looped sutures can be introduced in flexor tendon repair by the use of 23 G hypodermic needle and conventional 4.0 or 5.0 sutures. This is an alternative when the custom made preformed sutures are not available. This can be practiced in zone 3 to zone 5 repairs. Technical difficulties limit its use in zone 2 repairs.

  16. Polypropylene nanogel: “Myth or reality”

    International Nuclear Information System (INIS)

    The objective of this work is the investigation of the nanogel and microgel formation in modified PP. The modified PP in pellets was synthesized by gamma irradiation of pristine PP under a crosslinking atmosphere of acetylene in dose of 5, 12.5 and 20 kGy, followed by thermal treatment for radical recombination and annihilation of the remaining radicals. The thin film gel of the polypropylenes was obtained by extraction in boiling xylene for period of 12 h at 138 °C, followed by decantation in beaker at room temperature of 25 °C with the total volatilization of the xylene and deposition of dried material film on glass substrate under agitation by Settling process. The thin film gel formed of pristine PP and modified PP (i.e., irradiated) was characterized using scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) and differential scanning calorimetry (DSC). The PP morphology indicated the nanogels and microgel formation with increase of spherulitic concentration and crystallinity at dose of 12.5 kGy. - Highlights: ? The formation of nanogels comes from irradiated sites prior to crosslink bonds. ? Evolution of nanogels in size creates domains with lower crosslink density and defects. ? In conclusion nanogel is present in the irradiated PP and has crystallinity.

  17. Aksa plans polypropylene joint venture

    International Nuclear Information System (INIS)

    Turkish acrylic fiber maker Aksa (Yalova), part of the Akkok textile conglomerate, is studying construction of a world-scale polypropylene (PP) plant as part of its diversification plans. The company says it is engaged in discussions with three 'multinations in the PP business' on the possibility of a joint venture. One of the firms is understood to be Amoco. Aksa is looking at three possible locations for the 100,000 m.t.-150,000 m.t./year plant: Yalova, near Istanbul, where its existing plants are located; Zonguldak, on the Black Sea coast; and within one of the existing complexes or a new site belonging to state-owned Petkim. Aksa has not yet discussed that option with Petkim, which recently received approval to build a $2.5-billion petrochemical complex. The Aksa PP plant would cost about $100 million and would use propylene from world markets. The onstream date depends on Aksa's ability to link up with a foreign partner, but it hopes to complete the unit within three years. Turkey has only one PP plant, a 65,000-m.t./year Petkim unit at Aliaga. The domestic market is currently two to three times that amount and is growing. Petkim also plans a 200,000-m.t./year PP plant as part of its new complex

  18. Adjustable sutures in eyelid surgery for ptosis and lid retraction.

    OpenAIRE

    Collin, J. R.; O Donnell, B. A.

    1994-01-01

    New techniques are described and illustrated for ptosis and lid retraction surgery in which the sutures holding the upper eyelid position are adjustable postoperatively. In the anterior approach, the sutures pass from the levator muscle through the anterior surface of the tarsal plate at the position of the skin crease and are tied at the skin crease incision. In the posterior approach, the sutures pass from the levator muscle through the cut upper edge of the tarsal plate and are tied at the...

  19. The Effect of Anchoring Sutures on Medicinal Leech Mortality

    OpenAIRE

    Davila, Victor J.; Hoppe, Ian C.; Landi, Rocco; Ciminello, Frank S.

    2009-01-01

    Objective: The implementation of leech therapy for surgical flaps is not always logistically easy or comfortable for patients or healthcare providers. We examine different methods of placing sutures in the medicinal leech, Hirudo medicinalis, to make the implementation of leech therapy easier. Methods: Sixteen leeches were randomly divided into 3 groups: a control group, a deep anchoring suture group, and a superficial anchoring suture group. The leeches were observed to determine if either o...

  20. Mechanics of cranial sutures during simulated cyclic loading.

    Science.gov (United States)

    Jasinoski, S C; Reddy, B D

    2012-07-26

    Previous computational and experimental analyses revealed that cranial sutures, fibrous joints between the bones, can reduce the strain experienced by the surrounding skull bones during mastication. This damping effect reflects the importance of including sutures in finite element (FE) analyses of the skull. Using the FE method, the behaviour of three suture morphologies of increasing complexity (butt-ended, moderate interdigitated, and complex interdigitated) during static loading was recently investigated, and the sutures were assumed to have linear elastic properties. In the current study, viscoelastic properties, derived from published experimental results of the nasofrontal suture of young pigs (Sus scrofa), are applied to the three idealised bone-suture models. The effects of suture viscoelasticity on the stress, strain, and strain energy in the models were computed for three different frequencies (corresponding to periods of 1, 10, and 100s) and compared to the results of a static, linear elastic analysis. The range of applied frequencies broadly represents different physiological activities, with the highest frequency simulating mastication and the lowest frequency simulating growth and pressure of the surrounding tissues. Comparing across all three suture morphologies, strain energy and strain in the suture decreased with the increase in suture complexity. For each suture model, the magnitude of strain decreased with an increase in frequency, and the magnitudes were similar for both the elastic and 1s frequency analyses. In addition, a viscous response is less apparent in the higher frequency analyses, indicating that viscous properties are less important to the behaviour of the suture during those analyses. The FE results suggest that implementation of viscoelastic properties may not be necessary for computational studies of skull behaviour during masticatory loading but instead might be more relevant for studies examining lower frequency physiological activities. PMID:22703899

  1. Effect of Braiding and Hot Stretching Conditions on Sutures Performances

    OpenAIRE

    Faten Debbabi; Saber Ben Abdessalem

    2011-01-01

    The success of wound healing depends on suture performances, such as slippage ratio, deformation recovery, knot performance and tensile properties. The main objective of this study is to determine the effect of manufacturing parameters related to braiding and hot stretching steps on suture performances. Obtained results showed that hot stretching contributes to macromolecular chains arrangement as well as suture performances and structural properties improving. The percentage of crystallinity...

  2. Radioactive suture in the treatment of head and neck cancer

    International Nuclear Information System (INIS)

    125I seeds in Vicryl suture have been used as a radioactive suture in 24 cases of advanced malignancy of the head and neck. Twelve cases had metastatic carcinoma attached to the internal or common carotid artery. The goal was to excise surgically as much tumor as possible, then implant any residual tumor with this radioactive suture which remains as a permanent implant (half-life of 60 days). This preliminary study shows that use of 125I impregnated Vicryl suture in this manner appears to produce improved long-term palliation and may increase local cure rates

  3. Flammability of polypropylene/organoclay nanocomposites

    International Nuclear Information System (INIS)

    The flammabilities of nanocomposites made with three polypropylene grades (homo and copolymers) with 5 wt % of organoclay (Cloisite 20A), 5 or 15 wt % of maleated polypropylene as compatibilizer, and 0, 0.5 or 1 wt % of cis-13-docosenamide (Erucamide) as co-intercalant, were studied using the horizontal burning test UL94HB. Masterbatches prepared in an internal mixer were diluted in the polypropylene matrix using a corotating twin-screw extruder, with different screw configurations and operating at 240 or 480 rpm. Results indicate that the high burning rate of the composites was not affected by the processing conditions. For all formulations was observed a significant reduction in smoke release, lack of dripping and the formation of a char surface layer, that protected the core of the samples. (author)

  4. Suture locking of isolated internal locking knotless suture anchors is not affected by bone quality

    Science.gov (United States)

    Woodmass, Jarret M; Matthewson, Graeme; Ono, Yohei; Bois, Aaron J; Boorman, Richard S; Lo, Ian KY; Thornton, Gail M

    2015-01-01

    Purpose The purpose of this study was to evaluate the mechanical performance of different suture locking mechanisms including: i) interference fit between the anchor and the bone (eg, 4.5 mm PushLock, 5.5 mm SwiveLock), ii) internal locking mechanism within the anchor itself (eg, 5.5 mm SpeedScrew), or iii) a combination of interference fit and internal locking (eg, 4.5 mm MultiFIX P, 5.5 mm MultiFIX S). Methods Anchors were tested in foam blocks representing normal (20/8 foam) or osteopenic (8/8 foam) bone, using standard suture loops pulled in-line with the anchor to isolate suture locking. Mechanical testing included cyclic testing for 500 cycles from 10 N to 60 N at 60 mm/min, followed by failure testing at 60 mm/min. Displacement after 500 cycles at 60 N, number of cycles at 3 mm displacement, load at 3 mm displacement, and maximum load were evaluated. Results Comparing 8/8 foam to 20/8 foam, load at 3 mm displacement and maximum load were significantly decreased (Pbone quality for anchors that, even in part, relied on an interference fit suture locking mechanism (ie, 4.5 mm PushLock, 5.5 mm SwiveLock, 4.5 mm MultiFIX P, 5.5 mm MultiFIX S). Bone quality did not affect the mechanical performance of 5.5 mm SpeedScrew anchors which have an isolated internal locking mechanism. Conclusion The mechanical performance of anchors that relied, even in part, on interference fit were affected by bone quality. Isolated internal locking knotless suture anchors functioned independently of bone quality. Anchors with a combined type (interference fit and internal locking) suture locking mechanism demonstrated similar mechanical performance to isolated internal locking anchors in osteopenic foam comparing similar sized anchors. Clinical relevance In osteopenic bone, knotless suture anchors that have an internal locking mechanism (isolated or combined type) may be advantageous for secure tendon fixation to bone. PMID:26124683

  5. Does UV disinfection compromise sutures? An evaluation of tissue response and suture retention in salmon surgically implanted with transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Ricardo W.; Brown, Richard S.; Deters, Katherine A.; Eppard, M. B.; Cooke, Steven J.

    2013-10-01

    Ultraviolet radiation (UVR) can be used as a tool to disinfect surgery tools used for implanting transmitters into fish. However, the use of UVR could possibly degrade monofilament suture material used to close surgical incisions. This research examined the effect of UVR on monofilament sutures to determine if they were compromised and negatively influenced tag and suture retention, incision openness, or tissue reaction. Eighty juvenile Chinook salmon Oncorhynchus tshawytscha were surgically implanted with an acoustic transmitter and a passive integrated transponder. The incision was closed with a single stitch of either a suture exposed to 20 doses of UV radiation (5 minute duration per dose) or a new, sterile suture. Fish were then held for 28 d and examined under a microscope at day 7, 14, 21 and 28 for incision openness, ulceration, redness, and the presence of water mold. There was no significant difference between treatments for incision openness, redness, ulceration or the presence of water mold on any examination day. On day 28 post-surgery, there were no lost sutures; however, 2 fish lost their transmitters (one from each treatment). The results of this study do not show any differences in negative influences such as tissue response, suture retention or tag retention between a new sterile suture and a suture disinfected with UVR.

  6. Polypropylene mesh repair of incisional hernia

    International Nuclear Information System (INIS)

    Objective: The purpose of this study is to report the results of tension-free repair of primary and recurrent incisional hernias using polypropylene (Prolene) mesh. Results: The mean age was 43.7 years. The only death occurred in a known cirrhotic presenting with obstructed hernia. Another patient was seen developing seroma and wound infection in one case. No recurrence was seen during the mean follow-up period of 2.2 years. Conclusion: the tension-free repair of incisional hernia, with polypropylene mesh in extra facial position, is safe and easy procedure with acceptable morbidity and no recurrence. (author)

  7. 21 CFR 878.4494 - Absorbable poly(hydroxybutyrate) surgical suture produced by recombinant DNA technology.

    Science.gov (United States)

    2010-04-01

    ...Absorbable poly(hydroxybutyrate) surgical suture produced by recombinant DNA technology...Absorbable poly(hydroxybutyrate) surgical suture produced by recombinant DNA technology...absorbable poly(hydroxybutyrate) surgical suture is an absorbable...

  8. Reacción tisular a materiales de sutura no absorbibles en piel de equinos Tissue reaction to nonabsorbable suture materials in horse skin

    Directory of Open Access Journals (Sweden)

    F Maldonado

    2006-01-01

    Full Text Available Se evaluó clínica e histológicamente el grado de reacción tisular frente a cuatro materiales de sutura no absorbibles (lino, nylon, caprolactam polimerizado y polipropileno, implantados en la piel de 8 equinos. Se determinó clínicamente el edema provocado y la ausencia o presencia de exudado a los 5 y 10 días de haber sido implantados los materiales de sutura, además al 10º día se realizó una biopsia para determinar histológicamente el grado de reacción tisular. Los resultados obtenidos mostraron que el lino causó un mayor edema al día 5, mientras que al día 10 el nylon y caprolactam provocaron un menor de edema. Con respecto a la presencia o ausencia de exudado, al día 5 la sutura de nylon fue la única que no presentó exudado en ninguno de los 8 ejemplares, sin embargo, al día 10, salvo un ejemplar que presentó exudado en todos los materiales, el nylon, caprolactam y polipropileno no presentaron exudado. En cuanto a la evaluación histológica tanto el nylon como el caprolactam mostraron menor grado de reacción tisular. En conclusión, el lino resultó tener el mayor grado de reacción tisular durante el presente estudio, y el nylon si bien es similar al caprolactam y polipropileno respecto a la reacción tisular, causó una menor cantidad de equinos con presencia de exudado que los otros materiales utilizados.The degree of tissue reaction of 4 nonabsorbable suture materials (linen, nylon, polymerized caprolactum and polypropylene implanted into health skin of 8 horses was clinically and histologically evaluated. Cutaneous oedema and absence or presence of the exudation were clinically evaluated 5 and 10 days following suture material implantation. Biopsies were taken to histologically evaluate tissue reaction at 10 days. The results obtained showed that linen caused more oedema by the 5th day, whereas the nylon and caprolactum had less oedema on the 10th day. With respect to the presence or absence of exudation, nylon was the only material which did not show exudation by the 5th day in any of the 8 samples, but on the 10th day, neither the nylon, caprolactum or polypropylene showed exudation, except one horse that showed exudation for all suture materials. The histological evaluation showed that nylon and caprolactum caused less tissue reaction. In conclusion, linen was found to have a higher degree of tissue reaction in the present study, and nylon although similar to caprolactum and polypropylene in terms of tissue reaction, caused less cases of exudate than the other suture materials used.

  9. Antibacterial-Coated Suture in Reducing Surgical Site Infection in Breast Surgery: A Prospective Study

    OpenAIRE

    Enora Laas; Amp Xe Cile Poilroux, C.; Amp Xe Zu, Corinne B.; Charles Coutant; Serge Uzan; Roman Rouzier; Elisabeth Chéreau

    2012-01-01

    Background. To reduce the incidence of microbial colonization of suture material, Triclosan- (TC-)coated suture materials have been developed. The aim of this study was to assess the incidence of suture-related complications (SRC) in breast surgery with and without the use of TC-coated sutures. Methods. We performed a study on two consecutive periods: 92 patients underwent breast surgery with conventional sutures (Group 1) and 98 with TC-coated sutures (Group 2). We performed subgroups analys...

  10. Degradation study of polypropylene (PP) and bioriented polypropylene (BOPP) in the environment

    OpenAIRE

    Carina Longo; Michele Savaris; Mára Zeni; Rosmary Nichele Brandalise; Ana Maria Coulon Grisa

    2011-01-01

    Polymers are vastly employed for numerous purposes in different industrial segments and generate soaring quantities of discarding in the environment. This research analyzed the degradability/biodegradability of polypropylene films (PP) and Bioriented polypropylene (BOPP) polymers after 11 months interred in the São Giácomo landfill in Caxias do Sul. Comparing the buried PP film to a sample of virgin PP, two peaks of degrading activity appeared at the TG curve as well as structure modificati...

  11. Nose tip refinement using interdomal suture in caucasian nose

    Directory of Open Access Journals (Sweden)

    Pasinato, Rogério

    2012-01-01

    Full Text Available Introduction: Refinement of the nose tip can be accomplished by a variety of techniques, but currently, the use of sutures in the nasal tip with conservative resection of the alar cartilage is the most frequently recommended approach. Objective: To classify the nasal tip and to demonstrate the interdomal suture applied to nasal tip refinement in the Caucasian nose, as well as to provide a simple and practical presentation of the surgical steps. Method: Development of surgical algorithm for nasal tip surgery: 1. Interdomal suture (double binding suture, 2. Interdomal suture with alar cartilage weakening (cross-hatching, 3. Interdomal suture with cephalic removal of the alar cartilage (McIndoe technique based on the nasal tip type classification. This classification assesses the interdomal distance (angle of domal divergence and intercrural distance, domal arch width, cartilage consistency, and skin type. Interdomal suture is performed through endonasal rhinoplasty by basic technique without delivery (Converse-Diamond technique under local anesthesia Conclusion: This classification is simple and facilitates the approach of surgical treatment of the nasal tip through interdomal suture, systematizing and standardizing surgical maneuvers for better refinement of the Caucasian nose.

  12. High-resolution sonography of the abnormal cranial suture

    International Nuclear Information System (INIS)

    Objective. The purpose of this investigation is to elucidate the sonographic features of abnormal major cranial sutures. Materials and methods. Eight excised synostosed suture specimens were evaluated. The high-resolution sonographic appearance was correlated with the histological section, plain radiographs, CT and MRI. Diastatic and molded sutures were also evaluated with sonography and compared with the normal cranial suture appearance. Results. Synostosed sutures demonstrated one or more of the following features: (a) loss of echo-poor fibrous gap between bony plates (five sagittal and coronal synostoses); (b) irregular thickened inner sutural margin (three lambdoid synostoses); (c) loss of bevelled edge (one lambdoid synostosis); (d) asymmetric anterior fontanelle (one coronal synostosis). Cranial molding results in an overlap of echogenic bony plates. Sutural width (the distance between bony plates) is increased in cases of elevated intracranial pressure. Conclusion. Sonography is an inexpensive, radiation-free modality which can confirm synostosis versus molding versus an underlying intracranial lesion as a cause of plagiocephaly. The high-resolution sonographic images also provide a relatively easy means to assess sutural width and may provide information in regard to increased intracranial pressure. (orig.)

  13. Radiodiagnosis of incompetent sutures of various anastomoses and diodenal stump

    International Nuclear Information System (INIS)

    A retrospective analysis of X-ray findings of 72 patients who early after different operations on the organs of the peritoneal cavity developed the incompetence of sutures of anastomoses or the sutured colon, is presented. The frequency of detection of direct signs in the development of incompetence of sutures of diffrent site has been shown. Four groups of patients have been singled out proceeding from the difference of X-ray symptoms revealed on examination of patients at varying time after opearation. The use of a multimodality X-ray study (a straight X-ray of the chest and retroperitoneal cavity, various contrast methods of examination) at early time after operation beginning from the 3d-4th day, makes it possible to reveal in time the incompetence of sutures of various anastomoses or the sutured colon in 2/3 of the patients examined and to reveal developing purulent complications - peritoneal cavity abscess, diffuse peritonitis

  14. Effect of Braiding and Hot Stretching Conditions on Sutures Performances

    Directory of Open Access Journals (Sweden)

    Faten Debbabi

    2011-01-01

    Full Text Available The success of wound healing depends on suture performances, such as slippage ratio, deformation recovery, knot performance and tensile properties. The main objective of this study is to determine the effect of manufacturing parameters related to braiding and hot stretching steps on suture performances. Obtained results showed that hot stretching contributes to macromolecular chains arrangement as well as suture performances and structural properties improving. The percentage of crystallinity of fabricated suture was ameliorated by hot stretching suture and reaches 25.51% under temperature of 170C and during 3 min. An increase of hot stretching load to 15 N reduces slippage ratio and improves percentage of deformation recovery as a consequence of the improving of macromolecular chains arrangement.

  15. Vlastnosti nových nanokompozit? titanové nanotrubky / polypropylen.

    Czech Academy of Sciences Publication Activity Database

    Mikešová, Jana; Šlouf, Miroslav; Gohs, U.; Popelková, Daniela; Vacková, Ta?ana; Vu, Ngoc Húng; Kratochvíl, Jaroslav; Zhigunov, Alexander

    Praha : ?eská spole?nost chemického inženýrství, 2013, D1.3-0057. [Konference chemického a procesního inženýrství /60./ - CHISA 2013. Srní (CZ), 14.10.2013-17.10.2013] R&D Projects: GA ?R GAP205/10/0348 Institutional support: RVO:61389013 Keywords : titanate nanotubes * polypropylene nanaocomposites * mechanical and thermal properties Subject RIV: CF - Physical ; Theoretical Chemistry

  16. Plant growth responses to polypropylene--biocontainers

    Science.gov (United States)

    The influence of bio-fillers incorporated into polypropylene (PP) on the growth of plants was evaluated. Biocontainers were created by injection molding of PP with 25-40% by weight of Osage orange tree, Paulownia tree, coffee tree wood or dried distillers grain and 5% by weight of maleated polypropy...

  17. Polypropylene/aspen/liquid polybutadienes composites.

    Czech Academy of Sciences Publication Activity Database

    Kokta, B. V.; Fortelný, Ivan; Kruliš, Zden?k; Michálková, Danuše

    Erfurt : Thüringisches Institut für Textil - und Kunststoff-Forschung e.V, 2005, S1-03/1-S1-03/7. [International Symposium on Materials /5./. Erfurt (DE), 01.09.2005-02.09.2005] Institutional research plan: CEZ:AV0Z40500505 Keywords : Polymer composites * cellulose fibers * polypropylene Subject RIV: CD - Macromolecular Chemistry

  18. Toxicity of pyrolysis gases from polypropylene

    Science.gov (United States)

    Hilado, C. J.; Schneider, J. E.; Brauer, D. F.

    1979-01-01

    A sample of polypropylene was evaluated for toxicity of pyrolysis gases, using the toxicity screening test method developed at the University of San Francisco. The gases from this sample appeared to be equivalent or less toxic than the gases from a sample of polyethylene under these particular test conditions. Carbon monoxide appeared to be the principal toxicant.

  19. Materiales de sutura quirúrgico / Surgical suture materials

    Scientific Electronic Library Online (English)

    Karina, Armas Moredo; Bárbaro A, Armas Pérez; Leandro, Segura Pujal; Joaquín, Márquez Hernández; Katia, Armas Moredo.

    2009-10-01

    Full Text Available Se realizó una revisión bibliográfica sobre el tema Materiales de sutura quirúrgica, tanto nacional como internacionalmente, tratando de encontrar la información más actualizada posible, tomando como base un trabajo publicado en una revista nacional en el año 1990 y una revisión bibliográfica nuestr [...] a presentada en el hospital Amalia Simoni en 1995. Se revisaron los materiales informativos de algunas casas comerciales y a partir de aquí, se expusieron las clasificaciones conocidas con los productos que la conforman y se ofrecieron las características del producto comercial y del fabricante. Se señalaron las ventajas de los materiales de sutura de origen sintético sobre los naturales que van siendo desplazados en su utilización y preferencia. Existe el interés de ayudar a mejorar el conocimiento sobre este tema a los profesionales de la salud, personal paramédico y en formación al igual que a médicos veterinarios. Abstract in english A bibliographical review on the topic of surgical suture material, so much national as internationally, trying to find the most up-to-date possible information, taking as base a work published in a national magazine in the year 1990 and a bibliographical review of ours presented in Amalia Simoni hos [...] pital in 1995. The informative materials of some business houses are reviewed and starting from here, the well-known classifications are exposed with the products that compose it and offering the characteristics of the commercial product and the manufacturer. The advantages of the suture materials of synthetic origin are pointed out on the natural ones that are displaced in their use and preference. It encourages us the interest of helping to improve the knowledge on this topic to the health professionals and in formation, paramedic personnel as well as to veterinary doctors.

  20. Suture-related pseudoinfection after total hip arthroplasty.

    Science.gov (United States)

    Pierannunzii, Luca; Fossali, Andrea; De Lucia, Orazio; Guarino, Arturo

    2015-03-01

    Absorbable sutures are widely used for wound closure after total hip replacement. Here we present two cases of suture-related foreign-body reaction that perfectly mimicked a periprosthetic joint infection, with sterile abscess formation and physical and laboratory signs of inflammation acutely presenting 7-8 weeks after surgery, at the time of suture absorption. Both recurred with analogous timing after irrigation and debridement, likely due to re-using the same suture material. Multiple negative microbiological samples and positive histological samples showing a foreign-body reaction are the fundamental steps towards the diagnosis of a suture-related pseudoinfection (SRPI). Only three other cases have been reported to date, but the recurrence, together with the self-healing course after relapse, represents a completely novel feature and possibly the strongest demonstration of the supposed aetiopathogenesis. The knowledge of this possible complication leads to some clinical implications: all potential periprosthetic joint infections should routinely undergo not only microbiological but also histological sampling; caution should be used when recommending prosthesis exchange for potential infections occurring in the time range of suture absorption; lastly, if SRPI is suspected, a suture with low propensity to induce foreign-body reactions should be chosen after irrigation and debridement and the volume of absorbable material left in the wound should be as small as possible. PMID:24916148

  1. Complications with mechanical suture use in colorectal surgery

    International Nuclear Information System (INIS)

    The great development of mechanical suture and its qualitative impact in colorectal surgery has not been able to avoid persistent mortality due to suture failure which is still about 5% and rectal stenosis, which is significantly higher than with manual sutures.The present paper analyses 63 cases of colorrectal anastomosis performed of coordination with mechanical suture at CASMU, in a period of four years (1991-1995).There were 51 rectum resections and colorrectal anastomosis and 12 reconstruction of intestinal transit.There were 28 females and 35 males with and average age of 66 years.Three patients died (4,7%), 20 (31,7%) suffered various complications among which some are pointed out in relation to mechanical suture to suture failures(3,1%) who died and 8 rectal stenosis(12,9%)with favourable evolution after dilations.The authors analyse the issues that incide on the production of complications in colorrectal surgery and conclude that the incidence of global complications in their series is elevated, although mortality, suture failure and rectal stenosis figures are comparable to those in international literature analysed.The incidence of machine width proximal ostomies and radiotherapy on the development of stenosis in our milieu require a multicentric studie with a greater number of patients

  2. Development of braided drug-loaded nanofiber sutures

    International Nuclear Information System (INIS)

    The objectives of this work are twofold. Firstly, while most work on electrospinning is limited to the development of only functional materials, a structural application of electrospun nanofibers is explored. Secondly, a drug-loaded tissue suture is fabricated and its various properties are characterized. Braided drug-loaded nanofiber sutures are obtained by combining an electrospinning process with a braiding technique followed by a coating procedure. Two different electrospinning techniques, i.e. blend and coaxial electrospinning, to incorporate a model drug cefotaxime sodium (CFX-Na) into poly(L-lactic acid) (PLLA) nanofibers have been applied and compared with each other. Properties of the braided drug-loaded sutures are characterized through a variety of methods including SEM, TEM and tensile testing. The results show that the nanofibers had a preferable micromorphology. The drug was incorporated into the polymer nanofibers homogeneously, with no cross-linking. The nanofibers maintained their fibrous structures. An in vitro release study indicates that the drug-loaded nanofibers fabricated by blend electrospinning and coaxial electrospinning had a different drug release behavior. An inhibition zone experiment shows that both sutures obtained from the nanofibers of the different electrospinning techniques had favorable antibacterial properties. The drug-loaded sutures had preferable histological compatibility performance compared with commercial silk sutures in anompared with commercial silk sutures in an in vivo comparative study.

  3. Crystallization and mechanical properties of the ultrafine ferric oxide-filled polypropylene and rheology of the filled polypropylene melt

    International Nuclear Information System (INIS)

    Full text: Polypropylene was first blended with a series of ultrafine powder of ferric oxide with average diameters 16.1 nm, 41.3 nm, 73.0 nm, 184.0 nm, and 660.6 nm. The rheological property of the filled polypropylene melt was accessed in terms of equilibrium torques by using a Brabender plasticoder. The stress-strain behaviour was examined by using an Instron tensile tester. The crystallizing and melting processes of the filled polypropylene were followed by a Perkin-Elmer differential scanning calorimeter. And the degree of crystallinity was determined by the WAXD analysis. The data showed that the filled polypropylene had crystallized at higher temperature than the unfilled polypropylene. Whereas the ? form crystallinity of the polypropylene remained unchanged after it had been filled with ultrafine ferric oxide. Young's modulus of the filled polypropylene at room temperature decreased with decreasing of the filler's average diameter. But tensile strength of the filled polypropylene increased, approaching to that of unfilled polypropylene as the filler's average diameter getting smaller. Elongation at break remained constant during changing of the filler size. Better fluidity was found for smaller filler filled polypropylene melt. All the results manifest more researches to be done into the promising ultrafine filler

  4. 21 CFR 870.3470 - Intracardiac patch or pledget made of polypropylene, polyethylene terephthalate, or...

    Science.gov (United States)

    2010-04-01

    ...Intracardiac patch or pledget made of polypropylene, polyethylene terephthalate, or polytetrafluoroethylene...Intracardiac patch or pledget made of polypropylene, polyethylene terephthalate, or polytetrafluoroethylene...intracardiac patch or pledget made of polypropylene, polyethylene terephthalate,...

  5. Radiation stability of polypropylene/lead zirconate composites

    International Nuclear Information System (INIS)

    The effects of PbZrO3 filler in polypropylene were studied by isothermal and nonisothermal chemiluminescence and FT-IR spectroscopy after ?(137Cs)-irradiation at 20, 50, 100 and 250 kGy relative to neat material. For the two filler concentrations (2 and 5 wt%) the improvement in radiation stability can be noticed. The increase in the filler concentration stabilizes polypropylene matrix, whose oxidation rate decreases sharply even at 250 kGy. The interaction of polypropylene matrix with filler is discussed based on the adsorption of free radicals on zirconate particles and the electronic coupling of radiolysis intermediates and filler cations. - Highlights: • Polypropylene is more stable under gamma irradiation in the presence of lead zirconate. • Intermediate temperatures around 100 °C reveal a partial oxidation of polypropylene substrate. • Radiation stability of polypropylene compounded with lead zirconate is remarkable, leading to different applications in the manufacture of membranes

  6. Effect of stabilizers on polypropylene composition resistance to ioniozing radiation

    International Nuclear Information System (INIS)

    Full text: Polypropylene is widely used for the manufacture of medical devices and pharmaceutical packaging that is in those areas where the products are usually sterilized. Radiation emanation is used for sterilization of such products, as it is the most efficient and environmentally friendly inducstrial method. Ionizing radiation significantly affects the physical and mechanical properties of polypropylene. Study of the influence of stabilizers on radiation resistance of polypropylene-based compositions was the aim of this work

  7. Validation of material model for polypropylene (PP)

    OpenAIRE

    Sælen, Kristin

    2012-01-01

    A hyperelastic-viscoplastic material model intended for thermoplastics has been developed by SIMLab at NTNU. This model formed the basis of the thesis, where a material model for the polymer polypropylene was calibrated and validated. Four rounds of material testing were carried out. Tension and compression tests formed the basis for a calibration of the material model. Two different component tests were used for validation; stretching of a plate with a hole and plate impact tests.The calibra...

  8. Polypropylene : Morphology, defects and electrical breakdown

    OpenAIRE

    Laihonen, Sari J.

    2005-01-01

    Crystal structure, morphology and crystallization kinetics of melt-crystallized polypropylene and poly(propylene-stat-ethylene) fractions with 2.7 to 11.0 mol% of ethylene were studied by differential scanning calorimeter, wide- and small-angle X-ray scattering, polarized light microscopy, transmission electron microscopy and infrared spectroscopy. With increasing ethylene content the poly(propylene-stat-ethylene) fractions showed unchanged crystallinity, increased unit cell volume and consta...

  9. The nonlinear viscoelastic behavior of polypropylene

    OpenAIRE

    Drozdov, A. D.; Christiansen, J. deC.

    2002-01-01

    A series of tensile relaxation tests is performed on isotactic polypropylene in the sub-yield and post-yield regions at room temperature. Constitutive equations are derived for the time-dependent response of a semicrystalline polymer at isothermal loading with small strains. Adjustable parameters in the stress-strain relations are found by fitting experimental data. It is demonstrated that the growth of the longitudinal strain results in an increase in the relaxation rate in...

  10. Synthesis of Poly(Propylene Fumarate)

    OpenAIRE

    Kasper, F. Kurtis; Tanahashi, Kazuhiro; Fisher, John P.; Mikos, Antonios G.

    2009-01-01

    This protocol describes the synthesis of 500 – 4000 Da poly(propylene fumarate) by a two-step reaction of diethyl fumarate and propylene glycol through a bis(hydroxypropyl) fumarate diester intermediate. Purified PPF can be covalently crosslinked to form degradable polymer networks, which have been widely explored for biomedical applications. The properties of crosslinked PPF networks depend upon the molecular properties of the constituent polymer, such as the molecular weight. The purity o...

  11. Residual stress distribution in extruded polypropylene pipes.

    Czech Academy of Sciences Publication Activity Database

    Poduška, Jan; Ku?era, J.; Huta?, Pavel; Šev?ík, Martin; K?ivánek, J.; Sadílek, J.; Náhlík, Luboš

    2014-01-01

    Ro?. 2014, ?. 40 (2014), s. 88-98. ISSN 0142-9418 R&D Projects: GA ?R(CZ) GAP108/12/1560 Institutional support: RVO:68081723 Keywords : polypropylene * extruded polymer pipe * residual stress * curved beam methodology * numerical simulations Subject RIV: JL - Materials Fatigue , Friction Mechanics Impact factor: 2.240, year: 2014 http://www.sciencedirect.com/science/article/pii/S0142941814001809

  12. Radiation cross-linking of montmorillonite/polypropylene composite

    International Nuclear Information System (INIS)

    Polypropylene/montmorillonite composite was prepared via melt compounding process. The dispersion of montmorillonite in the composite was analyzed by XRD (X Ray Diffraction) and TEM (Transmission Electron Microscope). Electronic radiation was applied to the composite in air. The effects of cross-linking agent and montmorillonite on polypropylene cross-linking was studied. The results indicated that cross-linking did not take place in absence of cross-linking agent, while in presence of both cross-linking agent and montmorillonite polypropylene cross-lining occurred in certain radiation dose range. The cross-linked polypropylene/montmorillonite composite exhibited improved mechanical properties. (authors)

  13. High strain rate behaviour of polypropylene microfoams

    Directory of Open Access Journals (Sweden)

    Martínez A.B.

    2012-08-01

    Full Text Available Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc. or personal safety (helmets, knee-pads, etc.. In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000?s?1 in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB. Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  14. Cyclic viscoelastoplasticity of polypropylene/nanoclay composites

    DEFF Research Database (Denmark)

    Drozdov, A.; Christiansen, Jesper de Claville

    2012-01-01

    Observations are reported on isotactic polypropylene/organically modified nanoclay hybrids with concentrations of filler ranging from 0 to 5 wt.% in cyclic tensile tests with a stress–controlled program (oscillations between various maximum stresses and the zero minimum stress). A pronounced effect of nanofiller is demonstrated: reinforcement with 2 wt.% of clay results in strong reduction of maximum and minimum strains per cycle and growth of number of cycles to failure compared with neat polypropylene. To rationalize these findings, a constitutive model is developed in cyclic viscoelasticity and viscoplasticity of polymer nanocomposites. Adjustable parameters in the stress–strain relations are found by fitting experimental data. The model correctly describes the growth of the ratcheting strain and shows that fatigue failure is driven by a pronounced increase in plastic strain in the crystalline phase. To assess the influence of loading conditions on the changes in the material parameters, experimental data on polypropylene are studied in cyclic tests with a strain–controlled program (oscillations between fixed maximum and minimum strains) and a mixed program (oscillations between various maximum strains and the zero minimum stress). Numerical simulation confirms the ability of the model to predict the evolution of stress–strain diagrams with the number of cycles.

  15. Utilização do laser de argônio na remoção de sutura corneana Use of argon laser in corneal suture removal

    Directory of Open Access Journals (Sweden)

    Edélcio Vieira

    2004-12-01

    Full Text Available OBJETIVO: Descrever a técnica da retirada de sutura em córnea clara, evitando-se o contato da parte externa do fio com o meio intra-ocular e avaliar se esse procedimento evitaria infecções. MÉTODOS: Foi realizado estudo retrospectivo de 1.233 casos de retirada de sutura de mononylon 10.0 em córnea clara, utilizando-se laser de argônio para cortar o fio, no qual se avaliou a incidência de infecções. RESULTADOS: Em 1.071 olhos, um tiro foi suficiente para cortar o ponto. Em 162 olhos, o tiro do laser atingiu a parte epitelial da sutura, sendo necessários disparos extras para cortar a parte intra-estromal e, assim, retirá-la sem que a parte externa do fio passasse pelo interior da córnea. Não ocorreram complicações após a retirada da sutura. CONCLUSÕES: A técnica utilizada mostrou-se eficaz na remoção das suturas e possivelmente apresenta risco menor de infecção, uma vez que a parte do fio sobrejacente ao epitélio não entra em contato com as camadas mais internas da córnea, nem com a câmara anterior, não tendo sido observado nenhum caso de infecção nesta pesquisa.PURPOSE: To describe the technique of clear-cornea suture removal, that avoids the contact of the external part of the thread with the intraocular medium, and to evaluate whether this procedure would prevent infections. METHODS: A retrospective study of 1.233 cases of clear-cornea mononylon 10.0 suture removal, by the use of an argon laser to cut the thread, was performed. Incidence of infection was then assessed. RESULTS: In 1.071 eyes, one shot was enough to cut the stitch. In 162 eyes, the laser shot hit the epithelial part of the suture, making new shots necessary to cut the intrastromal part, and thus to remove it assuring that the outer part of the stitch would not come in to contact with the interior of the cornea. There were no complications after suture removal. CONCLUSIONS: The technique has shown to be effective in suture removal. And, possibly, presents a lower risk for infection, since the external part of the thread does not come in to contact with the innermost parts of the cornea, or with the anterior chamber. No cases of infection have been observed during this research.

  16. SUTURE NON-SUTSRE CIRCUMFERENTIAL REPAIR OF CAROTID ARTERY

    Directory of Open Access Journals (Sweden)

    Jafar Nader

    1969-01-01

    Full Text Available plastic adhesives, normal butyl cyanoacrylate monomer, isobutyl cyanoacrylate monomer and methyl 2 _ cyaooacrylate monomer, have been utilized in a comparative study with 5-{ silk suture in the repair of transected carotid arteries. Follow _ up arteriog ramS indicate isobutyl cyanoacrylate monomer and normal butyl cyanoacrylate monomer as having the most impressive rerults with only tWO thrombosis each. The silk suture had three thromboses and the adhesive methyl 2 _ cyanoacrylate monomer had nine, one of which a delayed

  17. ADJUSTABLE SUTURE STRABISMUS SURGERY: A REVIEW OF 850 CASES

    OpenAIRE

    M.E. Latronico; A. Moramarco; L. Russo; G. Lasorella

    2010-01-01

    Purpose. The aim of the study is to investigate the relationship between the different kinds of squint and the adjustament re- quired in post-op. Methods. Our personal case histories concerns 850 patients that underwent adjustable suture strabismus surgery during the last ten years, examinated in our Department of Ophtalmology over the period 2000-2009. The same surgeon (G.L.) performed adjustable suture strabismus surgery as routine duties, whether on horizontal or vertical rectus muscles, b...

  18. Suturing technique for control of postkeratoplasty astigmatism and myopia.

    OpenAIRE

    Dursun, Dilek; Forster, Richard K.; Feuer, William J.

    2002-01-01

    PURPOSE: We previously demonstrated that selective suture removal reduces keratoplasty astigmatism; however, a myopic shift was induced with increasing number of interrupted sutures removed. This study is an attempt to determine the effects of a modified surgical technique on postkeratoplasty myopia, astigmatism, and anisometropia. METHODS: Optical penetrating keratoplasties were performed on 92 eyes of 84 patients. The study group consisted of 92 consecutive penetrating keratoplasties perfor...

  19. A transducer for measuring force on surgical sutures

    OpenAIRE

    Witte, Thomas H.; Cheetham, Jonathan; Rawlinson, Jeremy J.; Soderholm, L. Vince; Ducharme, Norm G.

    2010-01-01

    The objective of this study was to validate, both in vitro and in an ex vivo model, a technique for the measurement of forces exerted on surgical sutures. For this purpose, a stainless steel E-type buckle force transducer was designed and constructed. A strain gauge was mounted on the central beam of the transducer to measure transducer deformation. The transducer was tested and calibrated on a single strand of surgical suture during cyclic loading. Further validation was performed using a pr...

  20. Early Experience With Barbed Sutures for Abdominal Closure in Deep Inferior Epigastric Perforator Flap Breast Reconstruction

    OpenAIRE

    Blacam, Catherine; Colakoglu, Salih; Momoh, Adeyiza O.; Lin, Samuel J.; Tobias, Adam M.; Lee, Bernard T.

    2012-01-01

    Objective: Barbed sutures have recently been introduced for closure of surgical incisions. These self-anchoring sutures incorporate evenly spaced barbs in a circumferential distribution along their length, facilitating knotless wound closure and even distribution of tension along the suture line. In this study, we evaluated postoperative complications associated with the use of unidirectional barbed sutures compared with standard sutures for closure of the abdominal incision in deep inferior ...

  1. Cierre de la pared abdominal: qué técnica y qué sutura se deben usar / Closing the abdominal wall: what technique and type of suture to use

    Scientific Electronic Library Online (English)

    Carlos, Lehmann; Álvaro, Sanabria; Eduardo, Valdivieso; Gabriel, Gómez.

    2007-06-01

    Full Text Available Introducción: El cierre de la pared abdominal es un procedimiento frecuente en la práctica de los cirujanos generales. El tipo de cierre y el material de sutura en la mayoría de los casos se realizan y escogen en forma empírica. El presente estudio valora la mejor evidencia disponible sobre la técni [...] ca para el cierre de la fascia abdominal y el tipo de sutura. Métodos: Se realizó una búsqueda sistemática de la literatura y se evaluaron los artículos de más alta calidad (revisiones sistemáticas). Los resultados se analizaron particularmente. Resultados: La mejor técnica de sutura de la fascia abdominal es aquella con puntos continuos con material de absorción lenta (polidioxanona) o no absorbible (polipropileno), los cuales tienen índices de hernia incisional menores que las suturas de absorción rápida. Conclusiones: Es recomendable utilizar sutura de material de absorción lenta o no absorbible para el cierre de la pared abdominal. Abstract in english Introduction: Closure of the abdominal wall is a frequently performed procedure in general surgical practice. The type of closure and the suture material are often chosen on empirical bases. The present study evaluates the best evidence available regarding the technique of closure of the abdominal w [...] all and the best suture material to be used. Methods: A systematic literature search was undertaken and the best quality articles (systematic reviews) were analyzed. Results: The best technique appears to be the closure with interrupted sutures of slow absorption (polydioxanone) or non absorbable (polypropylene) material, which exhibit lower recurrence rates that those observed with materials of rapid absorption. Conclusions: It is recommended to utilize interrupted sutures of slow absorption or non absorbable material for closing the abdominal wall.

  2. Iatrogenic Ulnar Nerve Injury post Laceration Suturing – An Unusual Presentation

    Directory of Open Access Journals (Sweden)

    Murali Mothilal

    2013-07-01

    Full Text Available Introduction: Nerve entrapment while suturing a lacerated wound is a complication that is easily avoidable. We report a case low ulnar nerve palsy due to nerve entrapment while suturing a lacerated wound. Case Report: A 48 year old lady came with complaints of pain and a lacerated wound over the dorsomedial aspect of lower third of the left forearm. The lacerated wound was sutured elsewhere one week back. She had fracture of lower third of the ulna which was stabilised with plates and screws using a separate dorsal incision. She developed ulnar claw hand on the third postoperative day. Strength duration curve revealed neurotmesis of ulnar nerve. Ulnar nerve exploration was done and the nerve was found to be ligated at the site of original laceration. The ligature was released and nerve was found to be thinned out at the site. There was no neurological recovery at 5 months follow up and reconstruction procedures in form of tendon tranfer are planned for the patient. Conclusion: This is a case of iatrogenic ulnar nerve palsy which is very rare in our literature. This can be easily avoided if proper care is taken while suturing the primary laceration. A nerve can be mistakenly sutured for a bleeding vein and proper exposure while suturing will be necessary especially at areas where nerves are superficial. Keywords: Iatrogenic, ulnar nerve palsy

  3. Development of braided drug-loaded nanofiber sutures

    Energy Technology Data Exchange (ETDEWEB)

    Hu Wen [School of Materials Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China); Huang Zhengming [School of Aerospace Engineering and Applied Mechanics, Tongji University, 1239 Siping Road, Shanghai 200092 (China); Liu Xiangyang, E-mail: huangzm@tongji.edu.cn [Department of Physics, National University of Singapore, 2 Science Drive 3, 117542 (Singapore)

    2010-08-06

    The objectives of this work are twofold. Firstly, while most work on electrospinning is limited to the development of only functional materials, a structural application of electrospun nanofibers is explored. Secondly, a drug-loaded tissue suture is fabricated and its various properties are characterized. Braided drug-loaded nanofiber sutures are obtained by combining an electrospinning process with a braiding technique followed by a coating procedure. Two different electrospinning techniques, i.e. blend and coaxial electrospinning, to incorporate a model drug cefotaxime sodium (CFX-Na) into poly(L-lactic acid) (PLLA) nanofibers have been applied and compared with each other. Properties of the braided drug-loaded sutures are characterized through a variety of methods including SEM, TEM and tensile testing. The results show that the nanofibers had a preferable micromorphology. The drug was incorporated into the polymer nanofibers homogeneously, with no cross-linking. The nanofibers maintained their fibrous structures. An in vitro release study indicates that the drug-loaded nanofibers fabricated by blend electrospinning and coaxial electrospinning had a different drug release behavior. An inhibition zone experiment shows that both sutures obtained from the nanofibers of the different electrospinning techniques had favorable antibacterial properties. The drug-loaded sutures had preferable histological compatibility performance compared with commercial silk sutures in an in vivo comparative study.

  4. The fire resistance of concrete with polypropylene fibers

    OpenAIRE

    Corpas F.A.; González B; Gómez L.; Rosa F.; Figueroa J.M

    2013-01-01

    This paper presents the results and conclusions of an experimental study characterization performed on the polypropylene fibers for use in concretes (NPC, Normal Performance Concrete) to produce an improvement in the durability against exposure to high temperatures. It was used only one type of polypropylene fiber with two different lengths, 6?mm and 12?mm, to evaluate the effect of the length.

  5. Properties of antibacterial polypropylene/nanometal composite fibers

    Science.gov (United States)

    Melt spinning of polypropylene fibers containing silver and zinc nanoparticles was investigated. The nanometals were generally uniformly dispersed in polypropylene, but aggregation of these materials was observed on fiber surface and in fiber cross-sections. The mechanical properties of the resulted...

  6. Fracture Toughness Studies of Polypropylene- Clay Nanocomposites and Glass Fibre Reinfoerced Polypropylene Composites

    Directory of Open Access Journals (Sweden)

    A. Ramsaroop

    2010-12-01

    Full Text Available In this paper, a comparative study on the fracture toughness of woven glass fibre reinforced polypropylene, chopped glass fibre reinforced polypropylene and nanoclay filled polypropylene composites is presented. Nanoclays (Cloisite 15A of 1 wt. % to 5 wt. % were filled in polypropylene (PP matrix and they were subjected to fracture toughness stu-dies. The specimen with 5 wt. % nanoclay showed 1.75 times and 3 times improvement in critical stress intensity factor (KIC and strain energy release rate (GIC, respectively, over virgin PP. On the other hand, 3 wt. % nanoclay PP composites showed superior crack containment properties. These structural changes of composite specimens were examined using Transmission Electron Microscopy (TEM and X-ray diffraction (XRD methods. It showed that exfoli-ated nanocomposite structures were formed up to 3 wt. % nanoclay, whereas, intercalated nanocomposite structures formed above 3 wt. % nanoclay in the PP matrix. Furthermore, the woven fibre reinforced PP composites demonstrated superior crack resistant properties than that of clay filled nanocomposites and chopped fibre PP composites. However, KIC and GIC values for woven fibre composites were lesser than that of chopped fibre composites. Moreover, KIC and GIC values for both nanoclay filled PP composites and woven fibre composites are comparable even though the clay filled PP demonstrated catastrophic failure. Also, the crack propagation rate of PP-nanoclay composites is comparable to that of chopped fibre composites.

  7. Disposable circumcision suture device: clinical effect and patient satisfaction

    Directory of Open Access Journals (Sweden)

    Bo-Dong Lv

    2014-06-01

    Full Text Available In our experience patients undergoing circumcision are mostly concerned about pain and penile appearances. We conducted a prospective randomized trial to assess the benefits of a new disposable circumcision suture device (DCSD. A total of 942 patients were equally divided into three groups (conventional circumcision, Shang ring and disposable suture device group. Patients in the DCSD group were anesthetized with compound 5% lidocaine cream, the others with a 2% lidocaine penile block. Operation time, intra-operative blood loss, incision healing time, intra-operative and post-operative pain, the penile appearance and overall satisfaction degree were measured. Operation time and intra-operative blood loss were significantly lower in the Shang ring and suture device groups compared to the conventional group (P < 0.001. Intra-operative pain was less in the suture device group compared with the other two groups (P < 0.001; whereas post-operative pain was higher in the conventional group compared to the other two groups (P < 0.001. Patients in the suture device (80.57% and Shang ring (73.57% groups were more satisfied with penile appearances compared with the conventional circumcision group (20.06%, P < 0.05. Patients in suture device group also healed markedly faster than the conventional group (P < 0.01. The overall satisfaction rate was better in the suture device group (78.66% compared with the conventional (47.13% and Shang ring (50.00% groups (P < 0.05. The combination of DCSD and lidocaine cream resulted in shorter operation and incision healing times, reduced intra-operative and post-operative pain and improved patient satisfaction with the cosmetic appearances.

  8. Midwives conducting perineal repair: The Danish Suture Trial

    DEFF Research Database (Denmark)

    Kindberg, Sara

    2007-01-01

    Midwives conducting perineal repair: The Danish Suture Trial.     Background Suture techniques and materials for repair of 2nd degree perineal lacerations and episiotomies have been tested in several clinical trials. Danish midwives and obstetricians have developed a new, simple and time-efficient suture technique which needed systematic evaluation. Objective To compare two standardized suture techniques for perineal repair of 2nd degree perineal lacerations or episiotomies. Design and setting A double-blind randomised clinical trial conducted in Aarhus University Hospital, Denmark. Initiated August 2004, enrolment of patients finished October 2005. Sample size: 400. Inclusion: Healthy primipara sustaining a 2nd degree perineal laceration or an episiotomy following vaginal birth. Perineal repair was carried out by a midwife. Exclusion: Lacerations involving the sphincter ani, post partum haemorrhage >1000 ml, Diabetes, mental disorders. Both suture techniques were 2-layered using a polyglactin910 multifilament suture (Vicryl Rapid or Vicryl). Treatment A was a continuous suture technique and treatment B was interrupted, inverted stitches. Primary outcomes: Perineal pain and wound healing assessed day 1-2 and 10 post partum. Secondary outcomes: patient satisfaction with wound healing, need for secondary repair, superficial pain during intercourse.   Data management: Double entry of all data and intention-to-treat analysis.   Results The follow up rate was 97%. Baseline data were evenly distributed between the two treatment groups. Major difference in pain and healing was observed between spontaneous lacerations and episiotomies. Follow up 6 months post partum will be finished by April 2006.   Conclusion Primary results will be presented on the NFOG Congress in Göteborg, May 2006.

  9. Study of insertion force and deformation for suturing with precurved NiTi guidewire.

    Science.gov (United States)

    Wang, Yancheng; Chen, Roland K; Tai, Bruce L; Xu, Kai; Shih, Albert J

    2015-04-01

    This research presents an experimental study evaluating stomach suturing using a precurved nickel-titanium (NiTi) guidewire for an endoscopic minimally invasive obesity treatment. Precise path planning is critical for accurate and effective suturing. A position measurement system utilizing a hand-held magnetic sensor was used to measure the shape of a precurved guidewire and to determine the radius of curvature before and after suturing. Ex vivo stomach suturing experiments using four different guidewire tip designs varying the radius of curvature and bevel angles were conducted. The changes in radius of curvature and suturing force during suturing were measured. A model was developed to predict the guidewire radius of curvature based on the measured suturing force. Results show that a small bevel angle and a large radius of curvature reduce the suturing force and the combination of small bevel angle and small radius of curvature can maintain the shape of guidewire for accurate suturing. PMID:25480363

  10. Improvement in the thermal performance of polypropylene

    International Nuclear Information System (INIS)

    In the framework of the CRP our contribution consists of the two directions of investigation on the stabilization of polypropylene: one way follows the compatibilization of the blends of polypropylene with ethylene-propylene terpolymer in the presence of divinylbenzene, and the second way is represented by the nanocomposites polypropylene/calcium carbonate. The irradiation of ethylene-propylene diene terpolymer/polypropylene blends in the presence of divinylbenzene is an alternative procedure, which improves material lifetime and may be applied to material recycling. The selection of these systems is justified on the basis of their capacity on the providing free radicals. The two polymer components, EPDM and PP, can be degraded with various rates because of the different contents of methyl groups. The polymer samples consisted of both materials under various ratios (20:80, 40:60, 60:40 and 80:20); individual materials were also subjected to the action of (137Cs) ?-rays. Divinylbenzene, a hydrocarbon which plays the role of radical source was added iat the level of 5% (w/w). The stabilization effect was tested by two methods: oxygen uptake and IR spectroscopy at the characteristic bands (1720 cm-1 and 3350 cm-1) for carbonyl and hydroxyl groups, respectively. The ?-exposure induced a slower oxidative degradation in the presence of DVB. The carbonyl and hydroxyl indexes were calculated for all formulations. From oxidability investigatirmulations. From oxidability investigation the kinetic parameters for thermal oxidation of irradiated samples were calculated. Their modification depicts the radiochemical stability, which is an important feature in the long term applications. The ability of divinylbenzene in the radiation stabilization of studied polyolefin blends is discussed in relation with the modification of exposure dose and sample composition. The irradiation performed in air represents a proper test for the qualification of this polymeric system. Thermal and ? radiation stability of iPP containing CaCO3 nanoparticles were investigated by oxygen uptake procedure at 160oC. The loading of iPP matrix was maximum 25% (w/w). The behaviour on thermal oxidation was investigated for two formulations of iPP compounds differing by the surface characteristics of nanoparticles (i.e. uncoated and stearic acid-coated filler). Three irradiation doses (5, 15 and 25 kGy) were applied. The efficient protection of stabilizers that are present in the as-prepared formulations was emphasized by proper values of the kinetic parameters obtained for oxidation. The contribution of CaCO3 nanoparticles to the oxidative process of iPP is discussed. (author)

  11. The nonlinear viscoelastic behavior of polypropylene

    CERN Document Server

    Drozdov, A D

    2002-01-01

    A series of tensile relaxation tests is performed on isotactic polypropylene in the sub-yield and post-yield regions at room temperature. Constitutive equations are derived for the time-dependent response of a semicrystalline polymer at isothermal loading with small strains. Adjustable parameters in the stress-strain relations are found by fitting experimental data. It is demonstrated that the growth of the longitudinal strain results in an increase in the relaxation rate in a small interval of strains in the sub-yield domain. When the strain exceeds some critical value which is substantially less than the apparent yield strain, the relaxation process becomes strain-independent.

  12. Large Vertical Axis Rotations along Neotethyan Sutures in TURKEY

    Science.gov (United States)

    Ozkaptan, M.; Gulyuz, E.; Kaymakci, N.; Langereis, C. G.; Ozacar, A. A.; Lefebvre, C.

    2014-12-01

    Two Neotethyan Sutures,Izmir-Ankara and Intra-Tauride suture zones meet around Ankara region appx. at right angles.The northerly located Izmir-Ankara Suture zone follows approximately E-W trend and it makes a sharp approximately 90° bend at the east along the western margin of the Çankiri Basin.The Intra-Tauride suture follows approximately the Tuzgölü Fault Zone and trends NW-SE and seems to be overprinted by the structures related to the Izmir-Ankara suture zone. These two sutures meet southeastern corner of the Haymana Basin where the basin makes major eastwards counterclockwise bend.From west to East, the Haymana, Tuzgölü and Çankiri Basins straddle these suture zones and are developed in relation to the subduction and collision processes in the region, making them the perfect sites to unravel deformation history and paleogeography of the Neotethyan suture zones in the region. In order to accomplish this, the tectono-stratigraphic evolution of the basin and its paleogeographical positions, in different time slices, constructed by conducting a very detailed study on the Late Cretaceous to Recent infill of the Haymana, Tuzgölü, and Çankiri Basins. We collected more than 4500 sedimentary paleomagnetic samples for paleomagnetic purposes from 112 different locations within 250 km diameter area.Before the demagnetization process, nearly 3000 core specimens were measured for anisotropy of magnetic susceptibility (AMS) in order to understand deformation amounts and kinematics.The paleomagnetic results show that the region underwent strong clockwise and counterclockwise rotations more than 90° in places, resulting in the present geometry of the suture zones. The central part of the Haymana basin rotated as high as 90° counterclockwise while its northern part together with the southwestern part of the Çankiri basin and northern part of the Tuzgölü basin rotated approximately 30° clockwise contrary to almost all published paleomagnetic data from the region.The restored orientations based on this new paleomagnetic data indicate that Haymana, Tuzgölü Basin and the SW margin of the Çankiri basins were initially oriented N-S prior to Eocene.These results indicate that the most of the paleogeographical maps and evolutionary scenarios and models of the region requires major re-thinking and serious revisions.

  13. Mechanical Behavior of Bio-inspired Model Suture Joints

    Science.gov (United States)

    Li, Yaning; Lin, Erica; Ortiz, Christine; Boyce, Mary

    2012-02-01

    Suture joints of varying degrees of geometric complexity are prevalent throughout nature as a means of joining structural elements while providing locally tailored mechanical performance. Here, micromechanical models of general trapezoidal waveforms of varying hierarchy are formulated to reveal the role of geometric complexity in governing stiffness, strength, toughness and corresponding deformation and failure mechanisms. Physical constructs of model composite suture systems are fabricated via multi-material 3D printing (Object Connex500). Tensile tests are conducted on samples covering a range in geometry, thus providing quantitative measures of stiffness, strength, and failure. The experiments include direct visualization of the deformation and failure mechanisms and their progression, as well as their dependence on suture geometry, showing the interplay between shear and tension/compression of the interfacial layers and tension of the skeletal teeth and the transition in failure modes with geometry. The results provide quantitative guidelines for the design and tailoring of suture geometry to achieve the desired mechanical properties and also facilitate understanding of suture growth and fusion, and evolutionary phenotype.

  14. Recognizing surgeon's actions during suture operations from video sequences

    Science.gov (United States)

    Li, Ye; Ohya, Jun; Chiba, Toshio; Xu, Rong; Yamashita, Hiromasa

    2014-03-01

    Because of the shortage of nurses in the world, the realization of a robotic nurse that can support surgeries autonomously is very important. More specifically, the robotic nurse should be able to autonomously recognize different situations of surgeries so that the robotic nurse can pass necessary surgical tools to the medical doctors in a timely manner. This paper proposes and explores methods that can classify suture and tying actions during suture operations from the video sequence that observes the surgery scene that includes the surgeon's hands. First, the proposed method uses skin pixel detection and foreground extraction to detect the hand area. Then, interest points are randomly chosen from the hand area so that their 3D SIFT descriptors are computed. A word vocabulary is built by applying hierarchical K-means to these descriptors, and the words' frequency histogram, which corresponds to the feature space, is computed. Finally, to classify the actions, either SVM (Support Vector Machine), Nearest Neighbor rule (NN) for the feature space or a method that combines "sliding window" with NN is performed. We collect 53 suture videos and 53 tying videos to build the training set and to test the proposed method experimentally. It turns out that the NN gives higher than 90% accuracies, which are better recognition than SVM. Negative actions, which are different from either suture or tying action, are recognized with quite good accuracies, while "Sliding window" did not show significant improvements for suture and tying and cannot recognize negative actions.

  15. 2-hydroxyethyl methacrylate composite - polypropylene mesh for preventing peritoneal adhesions in female dogs Compósito 2-hidroxietil dimetacrilato-tela de polipropileno para prevenção de aderências peritoneais em cadelas

    Directory of Open Access Journals (Sweden)

    Marcelo Seixo de Brito e Silva

    2010-08-01

    Full Text Available PURPOSE: To evaluate whether the lining facing the visceral side of polypropylene mesh made with 2-hydroxyethyl methacrylate (p(HEMA hydrogel could avoid peritoneal adhesion in female dogs. METHODS: Eight animals (group PP had a polypropylene mesh implanted to correct a defect in the rectal abdominal muscle, whereas in the other group (group PH the polypropylene mesh was coated with p(HEMA composite on the surface facing the peritoneal area. RESULTS: Adhesions were observed on the mesh in 62.5% of the PP group. In the PH group adhesions were present only on the suture lines. CONCLUSION: p(HEMA hydrogel was well tolerated and effective in avoiding visceral and omental adhesions on the surface of the polypropylene mesh.OBJETIVO: Avaliar se o revestimento da face visceral de uma tela de polipropileno com 2-hidroxietil dimetacrilato (p(HEMA poderia evitar aderências peritoniais em cadelas. MÉTODOS: Em oito animais (Grupo PP foram implantadas telas de polipropileno para correção de um defeito do músculo reto abdominal, enquanto em outro grupo (Grupo PH fez-se a implantação de uma tela de polipropileno cuja face peritonial foi revestida por 2-hidroxietil dimetacrilato (p(HEMA. RESULTADOS: Foram observados 62,5% de aderências peritoniais sobre a tela nos animais do Grupo PP, enquanto que no Grupo PH estas não ocorreram, exceto sobre a linha se sutura. CONCLUSÃO: O hidrogel de p(HEMA foi bem tolerado pelos animais e mostrou-se efetivo na prevenção das aderências viscerais e omentais sobre a tela de polipropileno.

  16. 2-hydroxyethyl methacrylate composite - polypropylene mesh for preventing peritoneal adhesions in female dogs / Compósito 2-hidroxietil dimetacrilato-tela de polipropileno para prevenção de aderências peritoneais em cadelas

    Scientific Electronic Library Online (English)

    Marcelo Seixo de Brito e, Silva; Renato Miranda de, Melo; Liliana Borges de, Menezes; Sonia Maria, Malmonge; Leandro Guimarães, Franco; Neusa Margarida, Paulo.

    2010-08-01

    Full Text Available OBJETIVO: Avaliar se o revestimento da face visceral de uma tela de polipropileno com 2-hidroxietil dimetacrilato (p(HEMA)) poderia evitar aderências peritoniais em cadelas. MÉTODOS: Em oito animais (Grupo PP) foram implantadas telas de polipropileno para correção de um defeito do músculo reto abdom [...] inal, enquanto em outro grupo (Grupo PH) fez-se a implantação de uma tela de polipropileno cuja face peritonial foi revestida por 2-hidroxietil dimetacrilato (p(HEMA)). RESULTADOS: Foram observados 62,5% de aderências peritoniais sobre a tela nos animais do Grupo PP, enquanto que no Grupo PH estas não ocorreram, exceto sobre a linha se sutura. CONCLUSÃO: O hidrogel de p(HEMA) foi bem tolerado pelos animais e mostrou-se efetivo na prevenção das aderências viscerais e omentais sobre a tela de polipropileno. Abstract in english PURPOSE: To evaluate whether the lining facing the visceral side of polypropylene mesh made with 2-hydroxyethyl methacrylate (p(HEMA)) hydrogel could avoid peritoneal adhesion in female dogs. METHODS: Eight animals (group PP) had a polypropylene mesh implanted to correct a defect in the rectal abdom [...] inal muscle, whereas in the other group (group PH) the polypropylene mesh was coated with p(HEMA) composite on the surface facing the peritoneal area. RESULTS: Adhesions were observed on the mesh in 62.5% of the PP group. In the PH group adhesions were present only on the suture lines. CONCLUSION: p(HEMA) hydrogel was well tolerated and effective in avoiding visceral and omental adhesions on the surface of the polypropylene mesh.

  17. Management of equine skull fractures using fixation with polydioxanone sutures.

    Science.gov (United States)

    Schaaf, K L; Kannegieter, N J; Lovell, D K

    2008-12-01

    Ten horses presented with severe distortion of the facial contour, crepitus on palpation and mild to moderate epistaxis. Individual horses also showed ocular damage, ptosis, severe dyspnoea and movement of the facial bones concurrent with respiration. The fracture fragments were exposed using a large curvilinear incision and elevated using a retractor, periosteal elevator, chisel or Steinmann pin. The fracture fragments were unstable following reduction and fixation was necessary. Stabilisation was achieved with polydioxanone sutures placed through holes drilled in opposing sides of the fracture lines. Polydioxanone sutures provided good stability and had better handling properties than wire. There was good apposition of fracture edges and minimal complications. Use of polydioxanone sutures can also avoid the expense and complexity of plate fixation in selected cases, and should be considered as an alternative to fixation with stainless steel wire in any facial fracture that adjoins stable bone. PMID:19076771

  18. Interrupted or continuous-intradermal suturing? Statistical analysis of postoperative scars

    Directory of Open Access Journals (Sweden)

    Elif Sar?

    2014-12-01

    Full Text Available Background and Design: Postoperative scar development is an important problem for patients treated in plastic surgery clinics. Most patients think that continuous intradermal suturing is superior to interrupted suturing because they assume that it creates less scarring. We evaluated scars that form following intradermal and interrupted suturing. This article presents our controlled study that objectively compared the scars on patients' faces using a wound evaluation scale. Materials and Methods: Thirty-five patients, who had undergone operations on the bilateral cheeks, were included in this study. Thirty patients were female; five patients were male. Their mean age was 40.05 years. The average scar evaluation time after surgery was 9.05 months. Elliptical excisions were made on the lesions under local anesthesia. The incisions on the right cheeks were sutured with 6/0 monofilament nonabsorbable sutures using the continuous intradermal suturing technique. The left cheek incisions were sutured with same sutures using the interrupted suturing method. Results: The patients were evaluated 7–11 months after operation (mean: 9.05 months using the Stony Brook Scar Evaluation Scale. A Related Samples T-test was used for statistical evaluation of the differences between the suturing techniques. No significant differences were noted in scar formation between the two suturing methods (p>0.05. Conclusion: We found no differences in scar formation between the two frequently used suturing techniques studied here. We believe that the suturing technique is a less important determinant of scar formation than are other factors.

  19. Nanoparticle effects during pressure-induced crystallization of polypropylene

    International Nuclear Information System (INIS)

    We describe here phase and morphological changes that are induced when polypropylene containing dispersion of nanoclay is isothermally crystallized in the pressure range of 0.1-200 MPa. To delineate and separate the effects of applied crystallization pressure from nanoparticle effects, a relative comparison is made between neat polypropylene and polypropylene containing dispersion of nanoclay under similar experimental conditions. The significant finding is that nanoparticles of clay interact with the host polypropylene in a manner such that they alter the structural morphology of ?- and ?-crystals of polypropylene presumably via nanoparticle interface driven evolution. Interestingly, nanoclay promotes the formation of ?-phase at low pressure, which is expected to have significant bearing on physico-chemical and mechanical properties. The equilibrium melting point measurements point to thermodynamic interaction between nanoclay and polypropylene, which is supported by the change in glass transition temperature and modification of absorption bands of polypropylene between 995 and 973 cm-1 corresponding to tertiary methyl skeletal in Fourier transform infrared spectrum

  20. Early skin reaction of polydioxanone suture material following septorhinoplasty.

    Science.gov (United States)

    Kuduban, Ozan; Denkta? Kuduban, Selma

    2015-01-01

    BACKGROUND Septorhinoplasty is a frequent surgical procedure used for both cosmetic and functional purposes. The technique varies from surgeon to surgeon and according to which suture material is used. While some surgeons prefer non-absorbable sutures, others prefer sutures with delayed absorption. These materials sometimes protrude from the skin and they may cause skin reactions. While these reactions are common in the late period, a skin reaction in the early period because of polydioxanone suture is extremely rare and to the best of our knowledge, this is the first such reported case in the literature. CASE REPORT A 25-year-old male patient underwent endonasal septorhinoplasty procedure with endo-tracheal general anesthesia. We hereby present the skin reaction because of frequently used polydioxanone suture on the 24th postoperative day and the management of this patient. We cut the suture at skin level and prescribed antibiotherapy, and we scheduled a follow-up for 10 days afterwards. The patient had no complaint and the control examination result was normal. CONCLUSIONS When performing septorhinoplasty operations, very rare complications of the procedure shouldn't be ignored and an informed consent must be obtained after explaining possible complications before the operation. This approach is important for increasing the patient compliance and proper follow-up for the patient. This way, especially post-operative early complications as our case will be able to be solved with close follow-up and intervention, before causing permanent damage. The relationship between patient who underwent rhinoplasty and the physician also has an important role on these follow-up visits. PMID:25951921

  1. Utilização do laser de argônio na remoção de sutura corneana / Use of argon laser in corneal suture removal

    Scientific Electronic Library Online (English)

    Edélcio, Vieira; Vinícius dos Santos Watzl Costa, Lima; Mírian da Silva, Azevedo; Wantuil Ferreira de, Souza Júnior; Roberto Reis Xavier dos, Santos; Ruiz Simonato, Alonso.

    2004-12-01

    Full Text Available OBJETIVO: Descrever a técnica da retirada de sutura em córnea clara, evitando-se o contato da parte externa do fio com o meio intra-ocular e avaliar se esse procedimento evitaria infecções. MÉTODOS: Foi realizado estudo retrospectivo de 1.233 casos de retirada de sutura de mononylon 10.0 em córnea c [...] lara, utilizando-se laser de argônio para cortar o fio, no qual se avaliou a incidência de infecções. RESULTADOS: Em 1.071 olhos, um tiro foi suficiente para cortar o ponto. Em 162 olhos, o tiro do laser atingiu a parte epitelial da sutura, sendo necessários disparos extras para cortar a parte intra-estromal e, assim, retirá-la sem que a parte externa do fio passasse pelo interior da córnea. Não ocorreram complicações após a retirada da sutura. CONCLUSÕES: A técnica utilizada mostrou-se eficaz na remoção das suturas e possivelmente apresenta risco menor de infecção, uma vez que a parte do fio sobrejacente ao epitélio não entra em contato com as camadas mais internas da córnea, nem com a câmara anterior, não tendo sido observado nenhum caso de infecção nesta pesquisa. Abstract in english PURPOSE: To describe the technique of clear-cornea suture removal, that avoids the contact of the external part of the thread with the intraocular medium, and to evaluate whether this procedure would prevent infections. METHODS: A retrospective study of 1.233 cases of clear-cornea mononylon 10.0 sut [...] ure removal, by the use of an argon laser to cut the thread, was performed. Incidence of infection was then assessed. RESULTS: In 1.071 eyes, one shot was enough to cut the stitch. In 162 eyes, the laser shot hit the epithelial part of the suture, making new shots necessary to cut the intrastromal part, and thus to remove it assuring that the outer part of the stitch would not come in to contact with the interior of the cornea. There were no complications after suture removal. CONCLUSIONS: The technique has shown to be effective in suture removal. And, possibly, presents a lower risk for infection, since the external part of the thread does not come in to contact with the innermost parts of the cornea, or with the anterior chamber. No cases of infection have been observed during this research.

  2. Polypropylene and polycarbonate radiosterilization: effects on the stress resistance

    International Nuclear Information System (INIS)

    The gamma radiation effect on polymer sterilization used in the fabrication of medical supplies, national polycarbonate and polypropylene, was studied in function of the tensile strength. During the polycarbonate irradiation occur the scission of polymer chain and the crosslinking/scission of the polypropylene, but in the sterilization dose, 25 kGy, does not occur expressive changes in the tensile strength. After the polypropylene sterilization the tensile strength continues increasing as consequence of the crosslinking. Since the sixth day the oxidation reaction predominates as consequence of the radical migration to the amorphous region. (author). 7 refs, 6 figs

  3. Filament Winding of Co-Extruded Polypropylene Tapes for Fully Recyclable All-Polypropylene Composite Products

    Science.gov (United States)

    Cabrera, N. O.; Alcock, B.; Klompen, E. T. J.; Peijs, T.

    2008-01-01

    The creation of high-strength co-extruded polypropylene (PP) tapes allows the production of recyclable “all-polypropylene” (all-PP) composite products, with a large temperature processing window and a high fibre volume fraction. Available technologies for all-PP composites are mostly based on manufacturing processes such as thermoforming of pre-consolidated sheets. The objective of this research is to assess the potential of filament winding as a manufacturing process for all-PP composites made directly from co-extruded tapes or woven fabric. Filament wound pipes or rings were tested either by the split-disk method or a hydrostatic pressure test in order to determine the hoop properties, while an optical strain mapping system was used to measure the deformation of the pipe surfaces.

  4. Degradation study of polypropylene (PP and bioriented polypropylene (BOPP in the environment

    Directory of Open Access Journals (Sweden)

    Carina Longo

    2011-12-01

    Full Text Available Polymers are vastly employed for numerous purposes in different industrial segments and generate soaring quantities of discarding in the environment. This research analyzed the degradability/biodegradability of polypropylene films (PP and Bioriented polypropylene (BOPP polymers after 11 months interred in the São Giácomo landfill in Caxias do Sul. Comparing the buried PP film to a sample of virgin PP, two peaks of degrading activity appeared at the TG curve as well as structure modification typified by occurrence of new absorption bands at FTIR, which can be credited to changes in crystallinity. Thermal analysis carried out on the buried PP and BOPP showed decreases in the percentage of crystallinity due to chain scission. The major reduction was observed in the PP, since its crystallinity is a consequence of polymerization instead of chain orientation processes, as in BOPP. Cracks and erosion of the polymer surface were detected in both PP and BOPP, indicating degrading processes by microorganisms.

  5. Degradation study of polypropylene (PP) and bioriented polypropylene (BOPP) in the environment

    Scientific Electronic Library Online (English)

    Carina, Longo; Michele, Savaris; Mára, Zeni; Rosmary Nichele, Brandalise; Ana Maria Coulon, Grisa.

    2011-12-01

    Full Text Available Polymers are vastly employed for numerous purposes in different industrial segments and generate soaring quantities of discarding in the environment. This research analyzed the degradability/biodegradability of polypropylene films (PP) and Bioriented polypropylene (BOPP) polymers after 11 months int [...] erred in the São Giácomo landfill in Caxias do Sul. Comparing the buried PP film to a sample of virgin PP, two peaks of degrading activity appeared at the TG curve as well as structure modification typified by occurrence of new absorption bands at FTIR, which can be credited to changes in crystallinity. Thermal analysis carried out on the buried PP and BOPP showed decreases in the percentage of crystallinity due to chain scission. The major reduction was observed in the PP, since its crystallinity is a consequence of polymerization instead of chain orientation processes, as in BOPP. Cracks and erosion of the polymer surface were detected in both PP and BOPP, indicating degrading processes by microorganisms.

  6. Endotracheal tube fixation methods for optimal stability: a comparison of adhesive tape, suture, and tape-suture fixation.

    Science.gov (United States)

    Farbod, Frank; Tuli, Puneet; Robertson, Bernard F; Jackson, Ian T

    2010-07-01

    Accidental extubation of an intubated patient is a serious consideration in the surgical patient. Adequate fixation in the intubated patient is essential to prevent potentially life-threatening complications. Several methods of endotracheal tube fixation have been described in the literature. In this study, we examine 3 common methods of fixation: adhesive tape alone, suture, and tape-suture. Testing occurred in a laboratory setting with 2 fresh cadavers. Endotracheal tubes were inserted, using the methods of fixation in question. We subjected each fixation technique to progressively increasing weight to determine which technique is most resistant to accidental removal. We found that fixation of the tube by combining tape around the tube with a suture through the tape is the best noninvasive technique of the 3 methods evaluated in cases where movement of the head is anticipated. PMID:20613600

  7. Prospective randomized controlled trial investigating the type of sutures used during hepatectomy

    OpenAIRE

    Norifumi Harimoto; Ken Shirabe; Tomoyuki Abe; Takafumi Yukaya; Eiji Tsujita; Tomonobu Gion; Kiyoshi Kajiyama; Takashi Nagaie

    2011-01-01

    AIM: To determine whether absorbable sutures or non-absorbable sutures are better in preventing surgical site infection (SSI), in this paper we discuss the results of a randomized clinical trial which examined the type of sutures used during hepatectomy. METHODS: All hepatic resections performed from January 2007 to November 2008 at the Department of Surgery at Iizuka Hospital in Japan were included in this study. There were 125 patients randomly assigned to an absorbable sutures (Vicryl) gro...

  8. A Study of the Efficacy of Antibacterial Sutures for Surgical Site Infection: A Retrospective Controlled Trial

    OpenAIRE

    Hoshino, Seiichiro; Yoshida, Yoichiro; Tanimura, Syu; Yamauchi, Yasushi; Noritomi, Tomoaki; Yamashita, Yuichi

    2013-01-01

    To reduce bacterial adherence to surgical sutures, triclosan-coated polyglactin 910 suture materials with antiseptic activity were developed. The aim of this study was to evaluate whether the incidence of surgical site infections can be reduced when triclosan-coated sutures are used. Until December 2009, we used conventional polyglactin 910 sutures (VICRYL, Ethicon) for the closure of the fascia in digestive tract surgery. Therefore, for the control group we retrospectively collected surveill...

  9. Comparison between Silk Sutures and Cyanoacrylate Adhesive in Human Mucosa- A Clinical and Histological Study

    OpenAIRE

    Kumar, M. Suresh; Natta, Sreelakshmi; Shankar, Gowri; Reddy, S. Hari Krishna; Visalakshi, D.; Seshiah, G. V.

    2013-01-01

    Background: Closing the surgical incision is an important step in the surgical procedures, the success of surgery is sometimes compromised by the defective suturing techniques or improper suturing materials, black silk sutures are more or less most often used materials in the day today surgical procedures, but these suture materials demand more time and effort from the surgeon and there is a need to substitute these materials with more user friendly and more successful wound closing materials...

  10. In Vivo Modulation of FGF Biological Activity Alters Cranial Suture Fate

    OpenAIRE

    Greenwald, Joshua A.; Mehrara, Babak J; Spector, Jason A.; Warren, Stephen M.; Fagenholz, Peter J; Smith, Lee P.; Bouletreau, Pierre J.; Crisera, Francesca E.; Ueno, Hikaru; Longaker, Michael T

    2001-01-01

    Gain-of-function mutations in fibroblast growth factor receptors have been identified in numerous syndromes associated with premature cranial suture fusion. Murine models in which the posterior frontal suture undergoes programmed fusion after birth while all other sutures remain patent provide an ideal model to study the biomolecular mechanisms that govern cranial suture fusion. Using adenoviral vectors and targeted in utero injections in rats, we demonstrate that physiological posterior fron...

  11. POLYPROPYLENE/CLAY NANOCOMPOSITES: SYNTHESIS AND CHARACTERIZATION

    Scientific Electronic Library Online (English)

    MÓNICA A, PÉREZ; BERNABÉ L, RIVAS; SADDYS M, RODRÍGUEZ; ÁLVARO, MALDONADO; CAROLA, VENEGAS.

    2010-12-01

    Full Text Available Polypropylene nanocomposites were synthesized by using the method of mixing in the molten state. Nanocomposites were obtained in twin-screw co-rotating extruders and the nanocomposites were prepared with percentage of nanoclay (C2) from 5 wt-%, with and without compatibilizer agent (PP-g-MA). The th [...] ermal (DSC, TGA), morphology (XRD, TEM), and dynamical mechanical (DMA) properties of the nanocomposites were characterized. All nanocomposites prepared are in intercalated state as corroborated by XRD and TEM. The Tm and Xc were not affected by the presence of clay, PP-g-MA, or processing support. The incorporation of clay and compatibilizer agent increases the thermal stability and heat deflection temperature (HDT).

  12. Development of radiation-resistant medical polypropylene

    International Nuclear Information System (INIS)

    In order to develop a radiation resistant polypropylene (PP) which can be sterilized by gamma radiation for medical use, optimal concentrations of various additives in PP were determined by observing the synergistic effect. The radiation durability of the disposable PP syringes prepared by the formulations was investigated. Their chemical and biological safety was also examined in accordance with the test method on the medical appliances stipulated by the Ministry of Health and Social Welfare. The samples with 0.01 % AO and 0.5 % PL showed sufficient radiation durability to maintain the mechanical strength even after 63 day aging at 60 deg C. The results of the chemical tests and the biological safety tests met the requirements of Korean and US pharmacopoeia. The PP medical products manufactured in accordance with the formulations could be sterilizable by radiation. (author)

  13. Mechanical Properties of Nanofilled Polypropylene Composites

    Directory of Open Access Journals (Sweden)

    Cristina-Elisabeta PELIN

    2015-06-01

    Full Text Available The paper presents a study concerning mechanical performance of thermoplastic nanocomposites based on isotactic polypropylene matrix, nanofilled with montmorillonite modified with quaternary ammonium salt and carboxyl functionalized carbon nanotubes, respectively, added in the same concentration relative to the matrix. The nanofilled and single polymer materials were obtained by simple melt compounding through extrusion process followed by injection molding into specific shape specimens for mechanical testing of the samples. Mechanical properties were evaluated by tensile and 3 point bending tests. In terms of modulus of elasticity, the results showed overall positive effects concerning the effect of nanofiller addition to the thermoplastic polymer. The fracture cross section of the tested specimens was characterized by FT-IR spectroscopy and SEM microscopy.

  14. Penile torsion correction by diagonal corporal plication sutures

    Directory of Open Access Journals (Sweden)

    Brent W. Snow

    2009-02-01

    Full Text Available Penile torsion is commonly encountered. It can be caused by skin and dartos adherence or Buck’s fascia attachments. The authors suggest a new surgical approach to solve both problems. If Buck’s fascia involvement is demonstrated by artificial erection then a new diagonal corporal plication suture is described to effectively solve this problem.

  15. Angiogenesis and osteogenesis in an orthopedically expanded suture

    Science.gov (United States)

    Chang, H. N.; Garetto, L. P.; Potter, R. H.; Katona, T. R.; Lee, C. H.; Roberts, W. E.

    1997-01-01

    The purpose of this study was to examine the angiogenic and the subsequent osteogenic responses during a 96-hour time-course after sutural expansion. Fifty rats were divided into: (1) a control group that received only angiogenic induction through injection of 5 ng/gm recombinant human endothelial cell growth factor (rhECGF); (2) an experimental group that received orthopedic expansion and rhECGF; (3) a sham group that received expansion and sodium chloride (NaCl) injection; and (4) a baseline group that received no expansion or injection. All rats were injected with 3H-thymidine (1.0 microCi/gm) 1 hour before death to label the DNA of S-phase cells. Demineralized sections (4 microm thick) were stained with hematoxylin and eosin. Angiogenesis and cell migration were analyzed with a previously established cell kinetics model. Analysis of variance was used to test the hypothesis that enhancement of angiogenesis stimulates reestablishment of osteogenic capability. Blood vessel number, area, and endothelial cell-labeled index significantly increased in experimental groups, but no difference was found between control and baseline groups. Labeled-pericyte index and activated pericyte numbers in the experimental group were also higher than in the sham groups. These results show that supplemental rhECGF enhances angiogenesis in expanded sutures but not in nonexpanded sutures. Data also suggest that pericytes are the source of osteoblasts in an orthopedically expanded suture.

  16. Penile torsion correction by diagonal corporal plication sutures

    Scientific Electronic Library Online (English)

    Brent W., Snow.

    2009-02-01

    Full Text Available Penile torsion is commonly encountered. It can be caused by skin and dartos adherence or Buck’s fascia attachments. The authors suggest a new surgical approach to solve both problems. If Buck’s fascia involvement is demonstrated by artificial erection then a new diagonal corporal plication suture is [...] described to effectively solve this problem.

  17. Penile torsion correction by diagonal corporal plication sutures

    OpenAIRE

    Snow, Brent W.

    2009-01-01

    Penile torsion is commonly encountered. It can be caused by skin and dartos adherence or Buck’s fascia attachments. The authors suggest a new surgical approach to solve both problems. If Buck’s fascia involvement is demonstrated by artificial erection then a new diagonal corporal plication suture is described to effectively solve this problem.

  18. Mechanical Properties of Recycled Compounds of Polypropylene for Building Products

    Directory of Open Access Journals (Sweden)

    Glaucea Warmeling Duarte

    2013-10-01

    Full Text Available The recycling of polymeric materials has been highly discussed due to economic and environmental factors. It is well known that, polypropylene can be used for many applications and, depending on the final characteristics that are necessary, they use different additives. So, this study aims to evaluate the mechanical properties of compositions containing recyclable polypropylene from different sources and with different composition and define the best composition using the maximum percentage of polypropylene with lower mechanical properties, which is a material considered difficult to incorporate in the process due to the high percentage of gas and impurities and the one with lowest cost. For the evaluation of mechanical properties, tensile and flexion tests were performed and, also, optical microscopy, which proved to be possible to use this kind of polypropylene in high percentages, since the conditions of mixture are guaranteed.

  19. Radiation cross-linking of montmorillonite/polypropylene composite

    International Nuclear Information System (INIS)

    Polypropylene/montmorillonite composite was prepared via melt compounding process. The dispersion of montmorillonite in the composite was analyzed by XRD (X-ray diffraction) and TEM (Transmission electron microscope). Electronic radiation was applied to make the composite radiation cross-linked in air. The effect of cross-linking agent and montmorillonite on the properties of polypropylene cross-linking was studied. The results indicated that cross-linking did not take place in absence of cross-linking agent, while in presence of both cross-linking agent and montmorillonite polypropylene cross-linking occurred in certain absorbed dose range. The cross-linked polypropylene/montmorillonite composite exhibited improved mechanical properties. (authors)

  20. Graft copolimerization of hydrophilic monomers onto irradiated polypropylene fibers

    International Nuclear Information System (INIS)

    A method of graft copolymerization of hydrophilic monomers, such as 1-vinyl-2-pyrrolidone, acrylonitrile, acrylic acid, and acrylamide, onto irradiated polypropylene fibers has been studied. ? ray as well as electron beam were employed for the irradiation processes. Graft-copolymerization kinetics and the properties of grafted fibers have been investigated. Moisture regain, dyes absorption, and melting point of the grafted fibers were found to increase with the increasing of the degree of grafting. Polypropylene for 1-vinyl-2-pyrrolidone grafted fibers showed excellent dye absorption for almost all kinds of dyes such as direct, basic, acid, reactive, disper, and naphthol dyes. However, for polypropylene acrylic acid grafted fibers, the colorfastness to washing was found to be unsatisfactory. The colorfastness to washing for polypropylene 1-vinyl-2-pyrrolidone grafted fibers was found to be fairly good for certain types of dyes such as vat and naphthol dyes. (author)

  1. Thermal conductivity of polypropylene filled with inorganic particles

    International Nuclear Information System (INIS)

    Highlights: ? Better thermal conductivity in PP samples filled with h-BN. ? Filler particle size affect composite thermal conductivity. ? Thermal conductivity was measured for different filler amount. -- Abstract: Boron and aluminium nitride, as well as carbon materials, were used as fillers for polypropylene to increase its thermal conductivity. Better thermal conductivity was observed for samples filled with nanosized BN. All composites show thermal stability up to 250 °C. Filling of polypropylene was shown to affect crystallinity degree, adding of BN and carbon nanotubes results in the increase in crystallinity of polypropylene. It was observed that BN forms chemical bonds with polymer matrix, whereas no evidence of such bonds was found in case of polypropylene filled with AlN particles

  2. Synthesis and Modification of Polypropylene by Radiation-induced Grafting

    OpenAIRE

    Feng Yuan; Junfu Wei; En-qi Tang; Kong-yin Zhao; Yang Xue

    2009-01-01

    Polypropylene fiber (PP) was radiation-induced graft polymerization of lauryl acrylate (LA) and butyl acrylate (BA)using a 60Co gamma radiation source. Then the grafted polypropylene fiber was characterized by a Fourier transforminfrared (FT-IR) spectrometer, Scanning Electron Microscopy (SEM), differential scanning calorimetry (DSC) andthermogravimetry (TG), which indicated that LA and BA have been grafted onto PP. The article focused on somefactors that influenced on the graft degree, such ...

  3. Environmental and Cost Assessment of a Polypropylene Nanocomposite

    OpenAIRE

    Roes, A. L.; Marsili, E.; Nieuwlaar, E.; Patel, Martin Kumar

    2007-01-01

    This paper describes a study on the use of a polypropylene (PP)/layered silicate nanocomposite as packaging film, agricultural film, and automotive panels. The study’s main question was ‘‘Are the environmental impacts and costs throughout the life cycle of nanocomposite products lower than those of products manufactured from conventional materials?’’ The conventional (benchmark) materials studied were pure polypropylene as packaging film, pure polyethylene as agricultural film, and ...

  4. Radiation resistant modified polypropylene; Polipropylen modyfikowany odporny radiacyjnie

    Energy Technology Data Exchange (ETDEWEB)

    Bojarski, J.; Zimek, Z. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)

    1997-10-01

    Radiation technology for production of radiation resistant polypropylene for medical use has been presented. The method consists in radiation induced copolymerization of polypropylene with ethylene and addition of small amount of copolymer of polyethylene and vinyl acetate. The material of proposed composition has a very good mechanical properties and elevated radiation resistivity decided on possibility of radiosterilization of products made of this material and designed for medical use. 3 figs, 3 tabs.

  5. Compounds made of aluminium and irradiation grafted polypropylene

    International Nuclear Information System (INIS)

    Radiation induced grafting of acrylic acid onto polypropylene surfaces by mutual radiation technique yields products which are especially suitable for making compounds with aluminium. Polypropylene can be used, for instance, as plates or foils, onto which grafting may be performed by a continuous or a discontinuous process. From these grafted plates or foils compounds have been made with aluminium, and their properties have been investigated in various tests. (author)

  6. Graft copolymerization of acrylonitrile onto polypropylene membrane by preirradiation

    International Nuclear Information System (INIS)

    A porous, graft copolymer and amidoxime group containing membrane were prepared by radiation graft copolymerization of acrylonitrile onto porous polypropylene. In order to calculate the grafting and amidoxime ratios of porous polypropylene-acrylonitrile graft copolymer. We have done CHN elemental analysis. It is obtained the result that grafting rate is increased to linear and value was about 75 percent at 20 Mrad dose rate. (Author)

  7. Application of gas chromatography to the investigations on polypropylene radiolysis

    International Nuclear Information System (INIS)

    Refinement of the gas chromatography (GC) instrumental approach permitted not only improvement of investigation in basic research, but also development of a new kind of polypropylene blends, more suitable for the production of medical devices and radiation sterilization. It has been shown, that using the GC method not only methane and carbon dioxide can be measured, but also the consumption of oxygen which reacts with free radicals on the polypropylene chain

  8. Polypropylene/graphite nanocomposites by in situ polymerization

    International Nuclear Information System (INIS)

    This work presents the synthesis of nanocomposites of polypropylene/graphite by in situ polymerization using metallocene catalyst and graphene nanosheets. Initially was analyzed which of the metallocene catalysts rac-Et(Ind)2ZrCl2 or rac-Me2Si(Ind)2ZrCl2 produces polypropylene with mechanical properties more relevant. Then it were performed the in situ polymerization reactions to obtain the nanocomposites. The polymeric materials were characterized by XRD, DSC, GPC and DMTA. (author)

  9. Investigation of bactericide systems using a microfiber polypropylene carrier

    Science.gov (United States)

    Petrova, A. Yu.; Chaikovskaya, O. N.; Plotnikova, I. V.

    2015-04-01

    The influence of pH of a medium on the attachment of TiO2 particles to the surface of a polypropylene microfiber is studied. The phototransformation of phenol in the presence of polypropylene microfibers is investigated by the fluorescence method and the method of electron absorption spectroscopy. After UV irradiation by excilamps, the photodecomposition of the toxicant proceeds in accordance with the molecular structure.

  10. Study on the Dynamic Performance of Polypropylene Fiber Reinforced Concrete

    OpenAIRE

    Zhang Ying; Zheng Chunhang; Wu Rujun; Chen Xi; Guoping Jiang

    2013-01-01

    The dynamic performance of polypropylene fiber reinforced concrete is studied with the SHPB experiment. The relationship of the strain-stress curves are all obtained in the experiment. The crack characteristics of polypropylene reinforced concrete and plain concrete are also investigated. Analyzed the relation between the character on the crack surface of concrete and material properties and the impact pressure. Also the multi-fractal characteristics are given on the crack surface of concrete...

  11. Physicomechanical properties of polypropylene composites filled by modified nano silicates

    International Nuclear Information System (INIS)

    This article is devoted to physicomechanical properties of polypropylene composites filled by modified nano silicates. Thus, the electron microscopy, mechanical, dynamical, and rheological study of polypropylene, filled by nano silica gel and silica gel modified by gamma-aminopropyltrimethoxysilane (C6H17O3N) was conducted. It was found that modification of silica gel surface by hydrophobic agent improve the interaction of filler particles with polymer matrix, improve the uniform distribution, prevent the agglomerate formation, increase the elasticity of composite material.

  12. Preparation of Polypropylene/Montmorillonite Nanocomposites Using Ionizing Radiation

    International Nuclear Information System (INIS)

    Polymer/clay nanocomposites are new generation materials that bring significant changes in mechanical, thermal and permeation properties of base polymers by low clay loading. In this study, polypropylene/montmorillonite nanocomposites were prepared by melt intercalation method by using batch type mixer. Two polypropylene samples with different melt flow indexes are used as the matrix, maleic anhydride grafted polypropylene (PP-g-MAH), and polypropylene granules oxidized by radiation/ozone are used as compatibilizer and unmodified clay (Na+ montmorillonite, MMT) as the filler. Aim of this study is to examine the effect of different compatibilizers in the mechanical properties of polypropylene composite. Firstly, PP/clay samples were prepared and the effect of clay was examined, then 5, 10, 20kGy oxidized/degraded polypropylenes were used as compatibilizer and, 10 kGy was determined to be the most suitable irradiation dose for the best compatibilizing effect. Polypropylene granules were ozonated until they contained carbonyl groups equivalent to 10kGy oxidized PP, which was checked by FTIR-ATR spectroscopy. UV-visible reflectance measurements were also made on film samples and no significant changes were observed in visible region. Nano structures of some nanocomposites were characterized by PALS (Positron Annihilation Lifetime Spectroscopy) where it was observed that the addition of clay decreased the number of free volume holes and free volume hole radia. The dispersion state of MMT within polymer matrix was analyzed by XRD (X-ray diffraction). Tensile tests were made and the effect of the addition of clay and compatibilizers investigated. At low melt flow index PP, 1% MMT of PP/10kGyPP/MMT nanocomposite showed an increase in E-modulus 26% and in tensile strength 8% as compared to those of pristine PP. In conclusion radiation degraded (chain scissioned and oxidized) PP has been found to show very good compatibilizing effect for the natural montmorillonite/polypropylene composites. (author)

  13. [Primary suture following the bile duct exploration in cholelithiasis].

    Science.gov (United States)

    Piecuch, Jerzy; Arendt, Jerzy; Gradzik, Robert; Rudzki, Marek; Sosada, Krystyn; Waniczek, Dariusz

    2004-01-01

    Classical performance of bile duct exploration is always strictly connected with the problem of an incised bile duct closure. In majority of surgical centers an external T-tube drainage was carried out in last century. But is an external drainage the best method to be used? The aim of the paper was to establish criteria for including (or excluding) patients to groups undergoing primary suture of bile duct. The comparison of the patients in whom bile duct exploration was followed by primary suture with the group in which T-tube was left in bile duct lumen was performed. Recently in our Department a classical method has been used to operate on 65 patients with cholelithiasis. In 42 patients a preoperatively planned bile duct exploration has been performed. In 14 patients a T-tube was left after the exploration, in 24 patients bile duct was closed with a primary suture. In other 18 patients with residual and recurrent bile duct stones T-tube was left in bile duct only in two patients. Based on literature analysis, our observations, and surgical experience criteria for including and excluding patients for primary suture of bile duct have been established. Groups of patients with and without T-tube were compared, considering complications and economic aspects of hospitalization. Our opinion is that whenever in specialized surgical centers detailed criteria are established and followed precisely, primary bile duct closure is a simple and safe procedure, responsible for few complications. The cost of hospitalization in the case of primary suture is half as much as the price of the hospitalization in the case of T-tube. PMID:15518068

  14. Unravelling the molecular control of calvarial suture fusion in children with craniosynostosis

    Directory of Open Access Journals (Sweden)

    Morris C Phillip

    2007-12-01

    Full Text Available Abstract Background Craniosynostosis, the premature fusion of calvarial sutures, is a common craniofacial abnormality. Causative mutations in more than 10 genes have been identified, involving fibroblast growth factor, transforming growth factor beta, and Eph/ephrin signalling pathways. Mutations affect each human calvarial suture (coronal, sagittal, metopic, and lambdoid differently, suggesting different gene expression patterns exist in each human suture. To better understand the molecular control of human suture morphogenesis we used microarray analysis to identify genes differentially expressed during suture fusion in children with craniosynostosis. Expression differences were also analysed between each unfused suture type, between sutures from syndromic and non-syndromic craniosynostosis patients, and between unfused sutures from individuals with and without craniosynostosis. Results We identified genes with increased expression in unfused sutures compared to fusing/fused sutures that may be pivotal to the maintenance of suture patency or in controlling early osteoblast differentiation (i.e. RBP4, GPC3, C1QTNF3, IL11RA, PTN, POSTN. In addition, we have identified genes with increased expression in fusing/fused suture tissue that we suggest could have a role in premature suture fusion (i.e. WIF1, ANXA3, CYFIP2. Proteins of two of these genes, glypican 3 and retinol binding protein 4, were investigated by immunohistochemistry and localised to the suture mesenchyme and osteogenic fronts of developing human calvaria, respectively, suggesting novel roles for these proteins in the maintenance of suture patency or in controlling early osteoblast differentiation. We show that there is limited difference in whole genome expression between sutures isolated from patients with syndromic and non-syndromic craniosynostosis and confirmed this by quantitative RT-PCR. Furthermore, distinct expression profiles for each unfused suture type were noted, with the metopic suture being most disparate. Finally, although calvarial bones are generally thought to grow without a cartilage precursor, we show histologically and by identification of cartilage-specific gene expression that cartilage may be involved in the morphogenesis of lambdoid and posterior sagittal sutures. Conclusion This study has provided further insight into the complex signalling network which controls human calvarial suture morphogenesis and craniosynostosis. Identified genes are candidates for targeted therapeutic development and to screen for craniosynostosis-causing mutations.

  15. Development of novel melt-compounded starch-grafted polypropylene/polypropylene-grafted maleic anhydride/organoclay ternary hybrids

    OpenAIRE

    E. Lafranche; R. Tessier; KRAWCZAK, P

    2012-01-01

    Starch-grafted polypropylene (PP-g-starch)/organoclay nanocomposites were melt-compounded using a corotating twin-screw extruder. Homopolymer or copolymer-based polypropylene-grafted maleic anhydrides (PP-g-MA) with different molecular weights and different maleic anhydride (MA) grafting levels were added at different weight contents as compatibilizer. Two organo-modified montmorillonites were used, the first one containing polar functional groups (Cloisite®30B) having affinity to the st...

  16. Closure of the rectus sheath with a continuous looped suture and the skin with staples in dogs: speed, safety, and costs compared to closure of the rectus sheath with interrupted sutures and the skin with a continuous subdermal suture.

    Science.gov (United States)

    Kummeling, A; van Sluijs, F J

    1998-10-01

    In dogs requiring a midline celiotomy, closure of the rectus sheath with a continuous polyglyconate looped suture and closure of the skin with stainless steel staples (group 1, 20 dogs) were compared with closure of the rectus sheath with interrupted polyglyconate sutures and closure of the skin with a continuous subdermal polyglactin suture (group 2, 20 dogs) with respect to speed, safety, and costs. The subcutis was closed with a continuous polyglactin suture in all dogs. The use of a looped suture saved 3.4 minutes and the use of staples saved 5.6 minutes. Total mean time saved for all layers was 7.7 minutes (38%). Wound healing was not significantly different between group 1 and group 2. There was one case of dehiscence of the rectus sheath in group 2 and two cases of wound infection in group 1. It was concluded that closing the rectus sheath with a continuous looped suture and the skin with staples is equally safe and significantly faster than closing the rectus sheath with simple interrupted sutures and the skin with a continuous subdermal suture. Additional costs were balanced by the reduction in surgery time. PMID:9810626

  17. Randomized clinical trial comparing manual suture and different models of mechanical suture in the mimicking of bariatric surgery in swine

    Directory of Open Access Journals (Sweden)

    Fernandes MA

    2014-02-01

    Full Text Available Marcos AP Fernandes,1 Bruno MT Pereira,2 Sandra M Guimarães,1 Aline Paganelli,3 Carlos Manoel CT Pereira,1 Claudio Sergio Batista4 1Institute of Obesity and Advanced Video Laparoscopic Surgery of Petropolis, Rio de Janeiro, Brazil; 2Division of Trauma, University of Campinas, São Paulo, Brazil; 3Laboratório de Patologia Micron Cell Diagnóstico, Rio de Janeiro, Brazil; 4Department of Gynecology and Obstetrics, Faculty of Medicine of Petropolis, Rio de Janeiro, Brazil Context and objective: Variations in the ability of surgeons served as motivation for the development of devices that, overcoming individual differences, allow the techniques to be properly performed, and of which the end result was the best possible. Every technique must be reproduced reliably by the majority of surgeons for their results to be adopted and recognized as effective. The aim of this study was to compare the results, from the point of view of anatomic pathology, of manual sutures versus mechanical sutures using different models of linear mechanical staplers, in the procedure of gastroenteroanastomosis and enteroanastomosis in swine. Methods: Thirty-six healthy, adult, male Sus scrofa domesticus pigs, weighing between 20.7 and 25.5 kg, were used. The swine were randomly divided into four groups of nine pigs, according to the type of suture employed: group A, manual suture with Polysorb® 3-0 wire; group B, 80-shear linear stapler (Covidien® Gia 8038-S; group C, 75-shear linear stapler (Ethicon® Tlc 75; and group D, 75-shear linear stapler (Resource® Yq 75-3. A temporal study was established on the seventh postoperative day for histopathological analysis, and the degree of inflammation, fibrosis, and newly formed vessels, as well as the presence or absence of granulation tissue, foreign body granuloma, and necrosis were all evaluated qualitatively and semiquantitatively. The results were analyzed statistically. Results: Observations during the histopathological analysis included the formation of foreign body granuloma in the gastroenteroanastomosis and enteroanastomosis in 88.9% of the swine that underwent manual suture and in none of the swine that underwent stapling. There was also a significant statistical difference among swine from Group A, and those from groups B, C and D regarding the degree of inflammation, being more intense in those swine that underwent manual suture. Conclusion: This study shows that both types of suture promoted proper healing of gastroenteroanastomosis and enteroanastomosis, although there was a higher degree of inflammation and an increased occurrence of foreign body granuloma in swine subjected to manual suture, although there have been similarities in safety, efficiency, and effectiveness between the models of linear mechanical staplers tested during the performance of these anastomoses on swine. Keywords: linear mechanical stapler, stapler, manual suture, surgery, gastroenteroanastomosis, enteroanastomosis, swine, randomized clinical trial

  18. Effect of wollastonite and talc on the micromechanisms of tensile deformation in polypropylene composites

    International Nuclear Information System (INIS)

    The work presented here describes the effect of wollastonite and talc on the micromechanisms of surface deformation and subsequent propagation into the bulk of low and high crystallinity polypropylenes during tensile straining. The potential of high resolution electron microscopy is utilized to examine deformation processes, and develop deformation mechanism maps. While mineral-reinforced polypropylenes exhibited an increase in tensile modulus, yield strength remained unaffected. Crystallization behavior indicated that the reinforcement minerals increase the rate of nucleation with consequent increase in percentage of bulk crystallinity. The reinforcement of polypropylene with wollastonite or talc alters the primary micromechanism of deformation from deformation bands/crazing in neat polypropylenes to wedge/ridge tearing in mineral-reinforced low crystallinity polypropylene composites. However, wedges were absent in high crystallinity polypropylene composites. The final fracture in reinforced polypropylene occurs by a mixed mode consisting of fibrillation and brittle mode, while crazing-tearing and brittle deformation are fracture modes for neat polypropylenes

  19. 78 FR 78748 - 2,5-Furandione, polymer With ethenylbenzene, Reaction Products With polyethylene-polypropylene...

    Science.gov (United States)

    2013-12-27

    ...regulations.gov. Follow the online instructions for submitting...ethenylbenzene, reaction products with polyethylene-polypropylene...ethenylbenzene, reaction products with polyethylene-polypropylene...United Nations Food and Agriculture Organization/World...ethenylbenzene, reaction products with...

  20. Plasma modification of polypropylene surfaces and its alloying with styrene in situ

    International Nuclear Information System (INIS)

    The treatment of polypropylene surfaces has been studied by dielectric barrier discharges plasma of Ar. The structure and morphology of polypropylene surfaces of Ar plasma modification are characterized by X-ray photoelectron spectroscopy, Fourier transform infrared spectrometers and scanning electron microscope. The modified by plasma treatment of iPP (isotactic polypropylene) surface properties have been examined in a determination of free radicals. The modified active surfaces of polypropylene can induce grafting copolymerization of styrene onto polypropylene. The structure of grafting copolymer is characterized and the grafting percent of styrene onto polypropylene is calculated. The homopolymer of styrene can be formed under grafting copolymerization of styrene onto polypropylene, which follows that the alloying of polypropylene with styrene is achieved in situ.

  1. Time to failure of biodegradable sutures: a new approach

    International Nuclear Information System (INIS)

    Data on the degradation and lifetime of biodegradable polyglycolic acid (PGA) sutures has been obtained. A new creep rupture technique was used with the samples immersed in a phosphate buffer solution to simulate in vivo fluids. Two groups of sutures were studied. Since irradiation is a convenient method of sterilization, one group consisted of 30 samples irradiated at 5 and 20 Mrad. A second group of 30 unirradiated samples was tested at temperatures from 30 to 450C. Failure occurs much faster at temperatures above 360C, the glass transition temperature for PGA, and for irradiated samples, the rate increasing with dose. At temperatures above glass transition the material becomes more accessible to hydrolysis which is generally accepted as the main mechanism for PGA degradation. Irradiation causes chain scission in non-crystalline regions, the sites responsible for hydrolysis. The failure data has been analysed using the Weibull distribution. (author)

  2. HUESOS SUTURALES EN EL PTERION / SUTURAL BONES IN THE PTERION

    Scientific Electronic Library Online (English)

    M. T. T., Braga; C., Gabrielli; A, De Souza; C. F. S., Rodrigues; J. C., Marino.

    Full Text Available Las variaciones de los huesos del cráneo son de interés para la anatomía, antropología física, imagenología y medicina legal. Con el propósito de aportar mayores detalles sobre los huesos suturales que se presentan en el pterion, fueron analizados 205 cráneos secos de individuos brasileños, adultos, [...] de ambos sexos, blancos y no blancos. El hueso sutural fue observado en 31 cráneos (15,1%), localizándose 19 en el lado derecho (61,3%), 8 en el izquierdo (25,8%) y 4 en ambos lados (12,9%). Con relación al sexo, 14 estuvieron presentes en cráneos masculinos (45,2%) y 17 en femeninos (54,8%). En relación al grupo étnico, 20 eran del grupo blancos (64,5%) y 11 de no blancos (35,5%). Las articulaciones de este hueso sutural con los huesos vecinos fueron clasificados en 4 tipos: Tipo I, donde se articuló con los huesos frontal, parietal, ala mayor del esfenoides y temporal, disposición encontrada en 17 cráneos (54,8%); Tipo II, donde se articuló con el parietal, temporal y ala mayor del esfenoides, encontrado en 11 cráneos (35,5%); Tipo III, donde se articuló con el temporal, frontal y ala mayor del esfenoides, observado en 2 cráneos (6,5 %) y Tipo IV, donde se articuló con el parietal, frontal y ala mayor del esfenoides, encontrado en 1 cráneo (3,2%). Correlacionando las variables lado, sexo, grupo étnico y hueso sutural, el análisis estadístico reveló que la presencia de estos huesos es significativa en los individuos blancos y en el lado derecho Abstract in english Cranium bones variations have been an object of interest for Anatomy, Physical Anthropology, X-Rays and Tomographic Images and Forensic Medicine. The aim of this article is to increase the knowledge of anatomical details about a sutural bone localized in the pterion. We observed 205 cranium of adult [...] cadavers from Brazilian origin, of both sexs, white and non white ethnic group. The sutural bone was found in 31 cranium (15.1%), 19 in the right side (61.3%), 8 in the left side (25.5%) and 4 in both sides (12.9%). In respect of the sex, 14 were observed in male cranium (45.2%) and 17 in female cranium (54.8%). With respect to the ethnic group, 20 cases (64.5%) corresponded to white individuals and 11 (35.5%) to non white. Sutural bone joints with the next bones, were classified in four groups: Type I, the sutural bone joined with the frontal, parietal, greater wing of the sphenoid and temporal bones, this type was observed in 17 cranium (54.8%); Type II, it joined with the greater wing of the sphenoid, parietal and temporal bones, this type was observed in 11 cranium (35.5%); Type III, the sutural bone joined with the greater wing of the sphenoid, temporal and frontal bones, this type was observed in only 2 cranium (6.5%) and Type IV, it joined with the greater wing of the sphenoid, parietal and frontal bones, this type was observed in only 1 cranium (3.2%). The statistical analysis of the different variables considered in this article showed that the presence of these bones is significative in white individuals and also in the right side in respect of all specimens

  3. Transcutaneous Serdev Suture For Buttock’s Lift

    OpenAIRE

    Nikolay Serdev

    2013-01-01

    This article presents the author's technique and experience in the treatment of the flaccid "unhappy buttock" form with his surgical procedure of buttock lift by suture, without incision scars. The author first presented this new operation technique on a national level at the 2nd Annual Meeting of the National Bulgarian Society for Aesthetic Surgery and Aesthetic Medicine in Sofia on March 18, 1994 [1] and internationally at many scientific meetings over the world [2, 3, 4…]. The result is a ...

  4. [In vitro study of Staphylococcus epidermidis adhesiveness to suture materials].

    Science.gov (United States)

    Arciola, C R; Buscaroli, S; Rocca, M; Farinetti, A; Fini, M; Manfrini, M; Giardino, R

    1990-03-01

    In surgical divisions, where you can find the highest percentage of hospital infections, the surgical wounds are definitively the most frequent localization. The aim of our study was to evaluate whether bacterial-biomaterial interactions could influence the growth of infections in sutured tissues. We prepared a method for in vitro bacterial adhesiveness testing based on turbidimetric analysis. The results obtained show a different grade of bacterial adhesion in relation to physical and chemical characteristics of the material examined. PMID:2223484

  5. Laminoplasty using Twinfix suture anchors to maintain cervical canal expansion

    OpenAIRE

    Yu, Hai-Long; Xiang, Liang-bi; LIU, Jun; Chen, Yu; Yu, Ming; Cao, Yan

    2010-01-01

    Open-door laminoplasty is a commonly performed procedure for the treatment of multiple level cervical spinal stenosis. One complication of this procedure is closure of the hinge and subsequent restenosis. Twinfix suture anchor was used in laminoplasty to stabilize cervical canal expansion. 53 patients with multiple level cervical spinal stenosis underwent laminoplasty. A unilateral open-door technique was performed for the lesion level and the elevated lamina was fixed to the lateral mass usi...

  6. Visual Measurement of Suture Strain for Robotic Surgery

    OpenAIRE

    Young Soo Park; John Martell; Thomas Elmer; Nachappa Gopalsami

    2011-01-01

    Minimally invasive surgical procedures offer advantages of smaller incisions, decreased hospital length of stay, and rapid postoperative recovery to the patient. Surgical robots improve access and visualization intraoperatively and have expanded the indications for minimally invasive procedures. A limitation of the DaVinci surgical robot is a lack of sensory feedback to the operative surgeon. Experienced robotic surgeons use visual interpretation of tissue and suture deformation as a surr...

  7. Doxycycline-coated sutures improve mechanical strength of intestinal anastomoses

    OpenAIRE

    Pasternak, Bjo?rn; Rehn, Martin; Andersen, Line; A?gren, Magnus S.; Heegaard, Anne-marie; Tengvall, Pentti; Aspenberg, Per

    2008-01-01

    Background and aims: After resection and repair of the intestines, tissue degradation leads to weakening of the repair site and a risk of postoperative leakage. Matrix metalloproteinases (MMPs) are thought to be responsible for collagenolysis in the direct vicinity of surgical sutures in many tissues. Several experimental studies show that MMP-inhibitors administered systemically alleviate postoperative weakening of intestinal anastomoses. We hypothesised that local delivery of MMP-inhibitors...

  8. Efficacy of b-lynch brace suture in postpartum haemorrhage

    International Nuclear Information System (INIS)

    Massive uncontrolled haemorrhage after childbirth is the leading cause of maternal death in developing countries. Postpartum haemorrhage is traditionally defined as blood loss of more than 500 ml after vaginal delivery and more than 1000 ml after caesarean section, but intraoperative estimation of blood loss is inaccurate. Uterine atony alone accounts for 75 - 90% of PPH. To estimate the effectiveness and safety of B-Lynch brace Suture in the management of primary postpartum haemorrhage (PPH). (author)

  9. IGF1R Variants Associated with Isolated Single Suture Craniosynostosis

    OpenAIRE

    Cunningham, Michael L; Horst, Jeremy A; Rieder, Mark J; Hing, Anne V; Stanaway, Ian B.; Sarah S. Park; Samudrala, Ram; Speltz, Matthew L.

    2011-01-01

    The genetic contribution to the pathogenesis of isolated single suture craniosynostosis is poorly understood. The role of mutations in genes known to be associated with syndromic synostosis appears to be limited. We present our findings of a candidate gene resequencing approach to identify rare variants associated with the most common forms of isolated craniosynostosis. Resequencing of the coding regions, splice junction sites, and 5? and 3? untranslated regions of 27 candidate genes in 1...

  10. Influence of different types of surgical suture material on the intensity of tissue reaction in oral cavity

    OpenAIRE

    Mirkovi? Siniša M.; Džambas Ljubiša D.; Selakovi? Sre?ko ?.

    2008-01-01

    Throughout the history the most diverse suture material have been used for closing and suturing surgical wounds. The four basic features of suture material are described: knot safety, stretch capacity, tissue reactivity and wound safety. Tissue reaction, even the minimum one, which develops during the first to seven days after applying the suture in the tissue. The aim of this study was to investigate influence of a monofilament suture material (nylon) on the intensity of local tissue reactio...

  11. Syneture stainless STEEL suture. A collective review of its performance in surgical wound closure.

    Science.gov (United States)

    Edlich, Richard F; Drake, David B; Rodeheaver, George T; Winters, Kathryne L; Greene, Jill A; Gubler, K Dean; Long, William B; Britt, L D; Winters, Samuel P; Scott, Christine C; Lin, Kant Y

    2006-01-01

    Syneture (division of U.S. Surgical, division of Tyco Healthcare, Norwalk, Connecticut, USA) STEEL sutures are monofilament stainless steel sutures composed of 316L stainless steel conforming to ASTM Standard F138 grade 2 (" Stainless steel bar and wire for surgical implant"). STEEL sutures meet all requirements established by the United States Pharmacopeia (USP) for nonabsorbable surgical sutures. Steel sutures are for use in abdominal wound closure, intestinal anastomosis, hernia repair, sternal closure, and skin closure. They are attached to the following types of surgical needles: Roto-Grip Needles and SCC Needle. The sutures and needles are packaged in a Mylar/Tyvek outer envelope. The purposes of this clinical review are two fold. First, we will report the performance of the Syneture STEEL suture product in the largest studies of suture performance ever reported in the literature. In addition, we will provide comprehensive information from the surgical literature that highlights the unique benefits of stainless steel sutures for the following wound closure techniques: sternal fixation, abdominal wound repair, inguinal hernia repair, and skin wound closure. Consorta Inc. (Rolling Meadows, Illinois), a leading healthcare resource management group purchasing organization, and Syneture, jointly with a clinician task force, designed a reproducible surgical evaluation program for needles and sutures in a large cooperative of healthcare systems. Because of the subjective nature of the more commonly used suture selection techniques, a nonexperimental observational study approach was designed to replace perception of performance characteristics with actual clinical experience. In a report involving 19 Consorta shareholder hospitals, they discussed the preliminary part (Phase I) of a large nonexperimental observational study of the clinical performance of surgical needles and sutures. Performance characteristics of the sutures and needles produced by Syneture that were evaluated in 3407 surgical procedures included packaging/ease of opening, needle strength and sharpness, tissue drag, knot security, tensile strength, clinically acceptable determinations, and clinically unacceptable determinations. In this preliminary study, the surgeons concluded that the needles and sutures were clinically acceptable in 98.1% of the evaluations. Armed with this favorable experience, we wanted to expand this observational study to an entirely new group of shareholder hospitals that had a larger number of participating hospitals (Phase I, 19 hospitals; Phase II, 42 hospitals). This more than doubling of hospital observational base dramatically increased the number of patients and performance evaluations. In the Phase II expanded program involving 42 hospitals, the number of patients (8939) and the number of evaluations (25,545) were more than twofold the preliminary study. In the phase I multicentric evaluation of Syneture surgical sutures, the performance of 9266 sutures was evaluated. Of these performance evaluations, 130 evaluations focused on Syneture STEEL sutures. The surgeons were especially pleased by the performance of this suture product, with 129 Syneture STEEL products being judged as clinically acceptable in their performance. Only one Syneture STEEL suture was judged to be unacceptable in its performance, resulting in a 99.2% acceptability rating. In the expanded phase II evaluation of Syneture suture products, the performance evaluation involved 25,545 surgical suture evaluations. The performance of Syneture STEEL sutures was judged in 215 cases. Of these product performance evaluations, 207 were judged to be clinically acceptable in their performance (96.3%). It is important to emphasize that the phase I and phase II observational studies evaluated the performance of other sutures besides monofilament steel sutures. These comprehensive suture and needle performance evaluations included the following additional sutures: Plain Gut, Mild Chromic Gut, Chromic Gut, DEXON II, DEXON S, MAXON, BIOSYN, SOFSILK, SURGILON, BRAL

  12. Magnetic fluids stabilized by polypropylene glycol

    International Nuclear Information System (INIS)

    A series of samples of magnetic fluids stabilized with low-molecular weight polypropylene glycol (PPG) of different molecular masses were synthesized. The use of PPG allowed the maximum extension of the carrier fluid range to include ethyl- and butyl-acetate, ethanol, butanol, acetone, carbon tetrachloride, toluene, kerosene and PPG itself. Magnetic and rheological properties of the samples were investigated. Based on the results of investigation it has been concluded that magnetic nanoparticles are covered by a monolayer of surfactant molecules. At low temperatures the propanol-based sample preserves fluidity up to -115 oC. Measurement of critical temperatures of other base fluids showed that alcohols are the best carrier medium. Coagulation stability of the ethanol-based ferrocolloid with respect to water and kerosene was explored. It has been found that kerosene, whose fraction by weight exceeds 22.5%, does not mix with the colloid. This effect can be used to produce magneto-controllable extractors of ethyl alcohol. Under the action of water the colloid coagulates, which allows one to substitute the carrier fluid and to separate the colloid into fractions. - Research highlights: ? PPG stabilizes the magnetic particles in the polar and non-polar media. ? The minimum operating temperature reaches -115 oC. ? Alcohols are the best environment for PPG-stabilized particles. ? PPG magnetic fluids can be used as magnetic extractors of alcohol.as magnetic extractors of alcohol. ? PPG MF can be divided into fractions by partial coagulation with water.

  13. Polypropylene matrix composites reinforced with coconut fibers

    Scientific Electronic Library Online (English)

    Maria Virginia, Gelfuso; Pedro Vieira Gurgel da, Silva; Daniel, Thomazini.

    2011-09-01

    Full Text Available Polypropylene matrix composites reinforced with treated coconut fibers were produced. Fibers chemically treated (alkalization-CCUV samples) or mechanically treated (ultrasonic shockwave-CMUV samples) were dried using UV radiation. The goal was to combine low cost and eco-friendly treatments to impro [...] ve fiber-matrix adhesion. Composite samples containing up to 20 vol. (%) of untreated and treated coconut fibers were taken from boxes fabricated by injection molding. Water absorption and mechanical properties were investigated according to ASTM D570-98 and ASTM D638-03, respectively. Electrical characterizations were carried out to identify applications of these composites in the electrical sector. NBR 10296-Electrical Tracking Standard (specific to industry applications) and conductivity measurements were obtained applying 5 kV DC to the samples. CMUV samples containing 5 vol. (%) fiber presented superior tensile strength values (?~28 MPa) compared to the untreated fibers composite (?~22 MPa) or alkali treatment (?~24 MPa). However, CMUV composites containing 10 vol. (%) fiber presented best results for the electrical tracking test and electrical resistivity (3 × 10(7) ?.m). The results suggest that composites reinforced with mechanically treated coconut fibers are suitable for electrical applications.

  14. Chemical imaging of wood-polypropylene composites.

    Science.gov (United States)

    Harper, David P; Wolcott, Michael P

    2006-08-01

    Recent investigations of wood plastic composites have revealed a detrimental effect of using lubricant systems in production. This includes nullifying part or all of the mechanical benefit of using a polar compatibilizer, maleic anhydride polypropylene (MAPP), in the composite formulation. This investigation utilizes lubricants labeled with deuterium in conjunction with Fourier transform infrared (FT-IR) spectroscopy to allow for the separation of individual lubricants from all other material constituents. All of the deuterium labeled lubricants, used without MAPP, revealed their expulsion from the wood interface during crystallization. MAPP coupling agent was found to exist near the wood, but it is unclear if any covalent bonding with the hydroxyl functionality on the wood surface occurred. The addition of zinc stearate lubricants appears to nullify the activity of the anhydride functionality near the wood surface as evidenced by a shift in the FT-IR spectra to the hydrolyzed form of the coupling agent. Most of the additives collect at the edges of the spherulites in mostly amorphous regions of the material. The consequence of this morphology may be a weak interface between crystallites. PMID:16925926

  15. Polypropylene matrix composites reinforced with coconut fibers

    Directory of Open Access Journals (Sweden)

    Maria Virginia Gelfuso

    2011-09-01

    Full Text Available Polypropylene matrix composites reinforced with treated coconut fibers were produced. Fibers chemically treated (alkalization-CCUV samples or mechanically treated (ultrasonic shockwave-CMUV samples were dried using UV radiation. The goal was to combine low cost and eco-friendly treatments to improve fiber-matrix adhesion. Composite samples containing up to 20 vol. (% of untreated and treated coconut fibers were taken from boxes fabricated by injection molding. Water absorption and mechanical properties were investigated according to ASTM D570-98 and ASTM D638-03, respectively. Electrical characterizations were carried out to identify applications of these composites in the electrical sector. NBR 10296-Electrical Tracking Standard (specific to industry applications and conductivity measurements were obtained applying 5 kV DC to the samples. CMUV samples containing 5 vol. (% fiber presented superior tensile strength values (?~28 MPa compared to the untreated fibers composite (?~22 MPa or alkali treatment (?~24 MPa. However, CMUV composites containing 10 vol. (% fiber presented best results for the electrical tracking test and electrical resistivity (3 × 10(7 ?.m. The results suggest that composites reinforced with mechanically treated coconut fibers are suitable for electrical applications.

  16. Nature of peroxy radicals in polypropylene

    International Nuclear Information System (INIS)

    Recent ESR studies on structure, motional character and decay reaction of peroxy radicals in irradiated polypropylene, which were made in our group, were summarized. Peroxy radicals must be trapped at the sites with various conformations and mobilities, in principle. However, we took an approximate consideration that the sites can be divided into two kinds, mobile and immobile. This interpretation was very successful in making good simulation procedures of ESR spectra. Internal rotation angles, which represent the orientations of the O-O group around C-O bond with respect to the adjacent C-C bond, both for mobile and immobile radicals were determined. The structure of the site for immobile radicals was found to be corresponding to gauche type and that for mobile one was found to be corresponding to skew type. Motional character of the peroxy radicals was found to be a rotation or rotational vibration around main chain axis. Decay reaction of the mobile peroxy radicals were interpreted by a diffusion controlled mechanism and the interpretation that immobile radicals do not take place in the decay reaction was reflected in the analysis. (author)

  17. Electrical properties of iron irradiated polypropylene films

    International Nuclear Information System (INIS)

    The effect of high-energy (50 MeV) Li3+ ion beam irradiation on polypropylene (PP) film has been studied in the f1uence range 2.4 x 1012-1.5 x 1014 ions/cm2. The a.c. electrical properties of PP films were measured in the frequency range from 0.05-100 kHz, and at temperature range between 30 and 140 degC. This study indicates two peaks at 60 degC and 120 degC with comparatively high magnitudes. There is an exponential increase in conductivity with log of frequency and the effect is significant at higher fluences. The loss factor (tan ?) vs frequency plot suggests that PP film based capacitors may be useful below 10 kHz. The capacitance is constant over a wide temperature range up to 130 degC. FTIR spectra of the PP films before and after irradiation indicate that intensity of C-H stretching vibration at 2900 cm-1 is modified. The presence of many new peaks with the increase of fluence suggests the formation of alkanes and alkynes which might be responsible for the observed changes in the dielectric and electrical properties of PP films. (author)

  18. Contribution of Thermal Modelisation to Understand adhesion Mechanisms in Extrusion Coating: Case of Polypropylene on Aluminium

    OpenAIRE

    Devisme, Samuel; Haudin, Jean-Marc; Agassant, Jean-François; Rauline, Damien; Chopinez, Fabrice

    2006-01-01

    A multilayered structure (polypropylene/grafted polypropylene/aluminium) manufactured by extrusion coating has been studied. The polypropylene film is extruded through a slit die, slightly stretched in air, coated on an aluminium foil in a laminator consisting of a chill roll and a flexible pressure roll, and finally cooled on successive chill rolls. Adhesive properties of polypropylene can be improved by grafting maleic anhydride on the polymer chain which may react with the aluminium surfac...

  19. ADJUSTABLE SUTURE STRABISMUS SURGERY: A REVIEW OF 850 CASES

    Directory of Open Access Journals (Sweden)

    M.E. Latronico

    2010-11-01

    Full Text Available Purpose. The aim of the study is to investigate the relationship between the different kinds of squint and the adjustament re- quired in post-op. Methods. Our personal case histories concerns 850 patients that underwent adjustable suture strabismus surgery during the last ten years, examinated in our Department of Ophtalmology over the period 2000-2009. The same surgeon (G.L. performed adjustable suture strabismus surgery as routine duties, whether on horizontal or vertical rectus muscles, but never on oblique muscles. Adjustments were always performed in the 24 postoperative hours. With regard to the relationship between previous surgeries, and requested regulation: 669 cases not underwent previous sur- gery; 181 cases peviously underwent surgery one or more times. results. First we seek for the statistical significant difference between the various results found, computing X2, ? and the rel- ative risk. We can conclude by saying that who made a vertical muscle squint surgery presents a relative risk of 3 times greater to take hypocorrection rather than hypercorrection and that who made before squint surgery presents a relative risk of 2,72 times greater to take regulation. Conclusions. We predicted this result because it confirms that the use of adjustable suture is the more frequent as the muscle fibrosis is the more significant. And the fibrosis is an usual outcome of previous squint surgery.

  20. Study of Maleic Anhydride Grafted Polypropylene Effect on Resin Impregnated Bamboo Fiber Polypropylene Composit

    Directory of Open Access Journals (Sweden)

    Gibeop Nam

    2014-11-01

    Full Text Available Previously, Polyvinyl Alcohol (PVA and phenolic resin were used for resin impregnated bamboo fiber reinforced PP composites which was manufactures for resin impregnated bamboo fiber with polypropylene (PP. Resin impregnation method can show improvement on tensile strength of fiber. However, to reduce the contact surface area and low inter-facial shear strength (IFSS between impregnated resin and matrix, using 40% weight fraction of bamboo fiber in PP matrix, PVA impregnated composites with mean flexural and tensile strength 10% higher than untreated composites were produced butphenolic resin impregnated fiber reinforced composition’s mechanical properties were decreased. In this study maleic anhydride grafted polypropylene (MAPP was used to increase interfacial shear strength between resin impregnated fiber and PP. With 10% MAPP, IFSS between resin impregnated fiber and PP increased more than 100% and reinforced composites. MAPP with untreated, phenolic resin and PVA impregnated cases showed similar mechanical properties. Yet in water absorption test, the PVA treatment with bamboo/PP composites increased water absorption ratio. But with 10% MAPP, matrix PP water absorption ratio decreased like phenolic resin impregnated fiber reinforced composites. 10% MAPP with resin impregnated bamboo fiber reinforced PP composites can improve IFSS, mechanical properties of composite and can decrease water absorption PVA resin impregnated bamboo fiber reinforced composites.

  1. Post irradiation degradation of polypropylene radiation durability of polypropylene stabilized with phenolic stabilizer (II)

    International Nuclear Information System (INIS)

    Post irradiation degradation of 60Co gamma irradiated polypropylene stabilized with a phenolic type stabilizer has been followed up to two years after being irradiated. The effectiveness of the stabilizer at various concentrations on the polypropylene samples irradiated up to 150 kGy has been studied and the buildup of carbonyl group in the irradiated samples measured. The obtained results indicated that the oxidative reactions are retarded by addition of stabilizer. The variation of bend strength of the irradiated samples with and without stabilizer was also followed. This property was found to be greatly improved for the stabilized samples irradiated at low doses. However at high doses the effectiveness of the stabilizer declined. In order to correlate these results with the change in the molecular weight of polymer, trends of the change in rheological behaviour such as melt viscosity (?a) and flow behavior parameters (K, n) of both stabilized and unstabilized samples have been investigated. Results showed that at low doses, addition of the stabilizer greatly reduces the extent of chain scission, and therefore, the mechanical properties of the irradiated polymer are retained. (Author)

  2. Toughening of polypropylene with ?-nucleated thermoplastic vulcanizates based on polypropylene/ethylene–propylene–diene rubber blends

    International Nuclear Information System (INIS)

    Highlights: • We designed and prepared ? nucleated thermoplastic vulcanizates. • We adopted the ? nucleated TPV to toughen polypropylene. • Greatly improved toughness of iPP, limited loss in strength and rigidity was achieved. • A toughening mechanism was proposed. - Abstract: A series of dynamically vulcanized isotactic polypropylene (PP)/ethylene–propylene–diene rubber thermoplastic vulcanizates (TPVs) containing different content of ?-nucleating agent (?-NA) were prepared and introduced into isotactic PP matrix as a toughening agent. The effect of ?-nucleated TPVs (?-TPVs) on the toughness and other properties of PP were studied. Differential scanning calorimetry and wide-angle X-ray diffraction results indicated that the ?-crystallinity and the relative content of ?-phase in ?-TPVs samples and the toughened blends increased with the content of ?-NA increasing. The notched impact strength of PP toughened by ?-TPVs, with limited loss in the tensile strength and rigidity, showed an almost linear increase with increasing ?-NA content. Especially when the content of ?-NA was 0.5 wt%, the impact strength of the toughened blends was ten times more than that of pure PP. The toughening mechanism based on classical rubber toughening mechanisms was discussed and a synergic toughening mechanism was proposed

  3. Synthesis, characterization and properties of carbon nanotubes microspheres from pyrolysis of polypropylene and maleated polypropylene

    International Nuclear Information System (INIS)

    Microspheres assembled from carbon nanotubes (MCNTs), with the diameters ranging from 5.5 to 7.5 ?m, were synthesized by means of pyrolysis of polypropylene and maleated polypropylene in an autoclave. The characterization of structure and morphology was carried out by X-ray diffractometer (XRD), field-emission scanning electron microscopy (FESEM), (high resolution) transmission electron microscope [(HR)TEM)], selected-area electron diffraction (SAED) and Raman spectrum. As a typical morphology, the possible growth process of MCNTs was also investigated and discussed. The results of nitrogen adsorption-desorption indicate that the Brunauer-Emett-Teller (BET) surface area (140.6 m2/g) of the MCNTs obtained at 600 oC is about twice as that (74.5 m2/g) of carbon nanotubes obtained at 700 oC. The results of catalytic experiment show that MCNTs based catalyst has higher catalytic activity than the carbon nanotubes based catalyst for the preparation of methanol and dimethoxy-ethane by oxidation of dimethyl ether.

  4. Análise das aderências resultantes da fixação de telas cirúrgicas com selantes de fibrina e sutura: modelo experimental intraperitoneal / Analysis of adhesions resulted from mesh fixation with fibrin sealant and suture: experimental intraperitoneal model

    Scientific Electronic Library Online (English)

    Juliano Hermes Maeso, Montes; André Vicente, Bigolin; Renata, Baú; Roberto, Nicola; João Vicente Machado, Grossi; Cláudia Juliana, Loureiro; Leandro Totti, Cavazzola.

    2012-12-01

    Full Text Available OBJETIVO: Comparar fixação cirúrgica de telas de polipropileno (PP) e telas de polipropileno revestido (PCD), usando fio de sutura de polipropileno e cola biológica, quanto à formação de aderências intraperitoneais. MÉTODOS: Amostra de 46 ratas Wistar, randomizadas em seis grupos: dois grupos-contro [...] le, com cinco ratas cada, que foram submetidos um à incisão medial (IM) e o outro à uma incisão em forma de U (IU); nenhum desses grupos recebeu tela. Dois grupos com tela de PP, um com dez ratas, fixada com sutura (PPF), e o outro, com seis ratas, fixada com cola biológica (PPC). E Dois grupos com tela de PCD, no primeiro, com dez animais, a tela foi fixada com sutura (PCDF), e no segundo, com dez animais, com cola biológica (PCDC). RESULTADOS: Após o prazo de 21 dias, os grupos-controle não apresentaram aderências significantes. O grupo PPC apresentou menor grau de aderência do que o grupo PPF (p=0,01). Não houve diferença entre as fixações nos grupos com PCD. CONCLUSÃO: A comparação da fixação apresentou diferença estatística significativa apenas à tela de PP, com menor grau de aderência utilizando a cola. As aderências se localizaram predominantemente nas extremidades das telas estudadas. Abstract in english OBJECTIVE: To compare surgical fixation of polypropylene mesh (PP) and coated polypropylene mesh (PCD) using polypropylene suture and fibrin glue, as for the formation of intraperitoneal adhesions. METHODS: A sample of 46 female Wistar rats were randomized into six groups: two control groups, with f [...] ive rats each, were subjected to one medial incision (MI) and the other to a U-shaped incision (UI), none of these groups received the mesh. Two groups of PP mesh, with ten rats, fixed with suture (PPF), the other with six rats, fixed with biological glue (PPC). And two groups of PCD mesh, at first, with ten animals, the mesh was fixed with sutures (PCDFs) and the second with ten animals with biological glue (PCDC). RESULTS: After 21 days, the control groups showed no significant adhesions. The PPC group showed a lower degree of adhesion than the PPF group (p = 0.01). There was no difference between the groups with PCD. CONCLUSION: Comparison of fixation was statistically different only with PP mesh, with lesser degrees of adherence when using the glue. Adhesions were predominantly located at the extremities of the meshes studied.

  5. Production of high melt strength polypropylene by gamma irradiation

    International Nuclear Information System (INIS)

    High melt strength polypropylene (HMS-PP) has been recently developed and introduced in the market by the major international producers of polypropylene. Therefore, BRASKEM, the leading Brazilian PP producer, together with EMBRARAD, the leading Brazilian gamma irradiator, and the IPEN (Institute of Nuclear Energy and Research) worked to develop a national technology for the production of HMS-PP. One of the effective approaches to improve melt strength and extensibility is to add chain branches onto polypropylene backbone using gamma radiation. Branching and grafting result from the radical combinations during irradiation process. Crosslinking and main chain scission in the polymer structure are also obtained during this process. In this work, gamma irradiation technique was used to induce chemical changes in commercial polypropylene with two different monomers, Tri-allyl-isocyanurate (TAIC) and Tri-methylolpropane-trimethacrylate (TMPTMA), with concentration ranging from 1.5 to 5.0 mmol/100 g of polypropylene. These samples were irradiated with a 60Co source at dose of 20 kGy. It used two different methods of HMS-PP processing. The crosslinking of modified polymers was studied by measuring gel content melt flow rate and rheological properties like melt strength and drawability. It was observed that the reaction method and the monomer type have influenced the properties. However, the concentration variation of monomer has no effectr has no effect

  6. Co-60 gamma radiation assisted diffusion of iodine in polypropylene

    International Nuclear Information System (INIS)

    Thin films of polypropylene having dimensions 50 mm x 15 mm x 350 ?m were immersed in 1 N iodine solution and then irradiated with Co-60 gamma radiation for the periods of 48, 96 and 144 h at the doses varying from 14.4 to 43.2 kGy. The films were also kept immersed in iodine solution for similar periods but without irradiation. Furthermore, the films were also directly-irradiated with Co-60 gamma radiation for similar periods and doses. The radiation-iodinated, plain-iodinated and directly-irradiated samples were characterized by using various techniques such as weight gain EDS, SEM, FTIR, UV-visible spectroscopy, contact angle and XRD. Weight gain, EDS and SEM collectively reveal that gamma irradiation enhances iodine intake in polypropylene. FTIR, EDS and contact angle measurements indicate that presence of iodine during irradiation resists radiation induced carbonylation of polypropylene. FTIR also shows presence of HOI (Hypoiodous acid) species instead of expected C-I bonds. UV-visible analysis unambiguously shows that presence of iodine enhances radiation induced band gap reduction process of polypropylene. XRD indicates that iodine decreases the crystallinity of polypropylene.

  7. Comparison of life cycle assessment for different volume polypropylene jars

    Directory of Open Access Journals (Sweden)

    Krki? Nevena M.

    2012-01-01

    Full Text Available When deciding what packaging is the most appropriate for a product there are many factors to be considered. One of them is the impact of the packaging on environment. In this work, life cycle inventory and life cycle assessment of two different volume packagings were compared. The data were collected on the types and amounts of materials and energy consumption in the process of packaging and distribution of hand cream packed in polypropylene jars of 200 and 350 mL. Life cycle inventory (LCI and life cycle impact assessment (LCA were calculated. It was found that the total mass flow was higher for the jars of 350 mL. After analyzing individual flows, it was found that in both cycles (polypropylene jars of 200 and 350 mL,the consumption of fresh water was a dominant flow. This fresh water flow is mostly (95% consumed in the injection molding process of manufacturing jars from polypropylene granules. The LCA analysis showed no significant difference in global warming potential between different volume jars. The process that mostly affected global warming was the production of polypropylene jars from polypropylene granules by injection molding for both jar volumes. Judging by the global warming potential, there is no difference of the environmental impact between investigated jars, but considering the mass flow and water consumption, more environmental friendly were the 200 mL jars.

  8. Histopathologic comparison of chromic catgut suture materials from Iran and abroad

    Directory of Open Access Journals (Sweden)

    Mehdi Marjani

    2009-01-01

    Full Text Available (Received 19 December, 2009 ; Accepted 3 April, 2010AbstractBackground and purpose: The chromic catgut sutures are the most common suture materials in surgical operations. The purpose of this in-vivo study was to evaluate the histopathological inflammatory reaction incited by four different kinds of catgut suture materials. Materials and methods: Twenty five adult New Zealand White rabbits, weighing approximately 2-3 kg, were divided into 5 groups of 5 rabbits in each group. Four types of catgut sutures were implanted in the dorsum and thigh muscles. After 2, 7, 14, 21 and 60 days, the animals were sacrificed and the sutures, subcutaneous and muscle tissues were removed from the implanted areas.Results: Statistical analysis for comparison of each two suture materials showed significant differences between groups (p<0.05 while ETHICON suture showed minimum inflammatory reaction and was considered the best. Conclusion: Uncontrolled raw materials of the catgut suture from the intestine of particular animals may cause a variety of pathological effects beyond the threshold set for medical surgery.Key words: Chromic catgut suture, implantation, suture material, pathology, rabbitJ Mazand Univ Med Sci 2009; 20(74: 33-42 (Persian.

  9. Influence of different types of surgical suture materials on mehanical damage of oral mucosa

    Directory of Open Access Journals (Sweden)

    Mirkovi? Siniša

    2011-01-01

    Full Text Available Introduction. Throughout history many kinds of different suture materials have been used for closing and suturing surgical wounds. Medical literature describes four basic characteristics of suture material: knot safety, tensile strength, tissue reaction and wound safety. The tissue reaction is reflected in an inflammatory response, which, though minimal, occurs during first two to seven days after implanting suture into the tissue. The aim of this research was to investigate whether different suture materials affect the development of decubital damage of oral mucosa, which to a great extent can compromise the process of wound healing. Material and methods. The investigation was designed as a prospective clinical study including 150 patients of both genders, aged between 25 and 60. The patients were distributed into three groups of 50 persons. The suture Black Silk was used in the first group, designated as a control group. Nylon and Vicril were used in the second and third group, i.e. experimental groups, respectively. Decubital damage of the surrounding soft tissues was the main parameter for monitoring the effects of selected suture materials on the oral mucosa. Conclusion. The comparison of results obtained for the investigated suture materials after suturing oral mucosa revealed that certain advan­tage could be given to synthetic monofilament suture materials

  10. Síntese da parede abdominal: avaliação de dois tipos de sutura contínua em ratos / Abdominal wall syntheses: comparison between two types of continuous suture

    Scientific Electronic Library Online (English)

    Vanessa Medeiros, Loureiro; Djalma José, Fagundes; Murched Omar, Taha.

    2003-06-01

    Full Text Available OBJETIVO: Comparar a sutura simples contínua e a sutura contínua em oito vertical no fechamento da parede abdominal de ratos. MÉTODOS: Quarenta e oito ratos machos Wistar, foram submetidos a laparotomia padronizada e fechamento da parede abdominal com sutura simples contínua (n=24) e sutura contínua [...] em oito-vertical (n=24), com fio de polipropileno. No 7° e 14° pós-operatório foram submetidos a eutanásia 12 animais de cada grupo e deles retirados a camada músculo-aponevrótica da parede abdominal envolvendo a cicatriz operatória e preparados para exames histológico e imunohistoquímico. Os segmentos levados ao exame histológico foram corados por Hematoxilina-eosina sendo feita observação qualitativa do processo cicatricial e Picrosirius red F3BA, para avaliação quantitativa do colágeno. Também foram estudadas as porcentagens de macrófagos na linha de sutura por imunohistoquímica. Para a quantificação de macrófagos e fibras colágenas foi utilizado avaliação histológica por digitalização de imagem, baseados nos princípios de espectrofotometria. Os dados encontrados foram analisados estatisticamente pelos testes qui-quadrado, exato de Fisher e Mann-Whitney (p Abstract in english PURPOSE: To establish morphologic relationship between the continuous "simple mass" suture and the continuous far-near, near-far mass suture of longitudinal midline abdominal incision. METHODS: A total of 48 male Wistar rats underwent longitudinal standard laparotomy with equal distribution to one o [...] f two groups: GI- continuous "simple mass" suture, GII-continuous far-near, near-far suture, both with polypropylene. On postoperative day 7th or14th, 12 animals of each group were submitted to euthanasia and anterior abdominal wall was removed (without skin) for histologic and immune- histochemistry analysis. The samples of the abdominal wall were stained by hematoxylin-eosin in order to performed a qualitative healing tissue reaction. Others samples were stained by Picrosirius red F3BA in order to performed a quantitative analysis of macrophages and collagen. Statistical analysis was done by use the chi-square test, Fisher exact test and Mann-Whitney variance test ( p

  11. Modification of polypropylene with radiation-treated wood fiber

    International Nuclear Information System (INIS)

    The dispersed wood material is used not only as filler for thermosetting polymers but also as a new type of fibrous additive for thermoplastics e.g. polypropylene. Benefit of this additive (filler or reinforcement) is determined by the coupling between the wood and the synthetic resin. Fibrous, dispersed wood material was preirradiated in air, treated with vinyl monomer containing polyester resin and then mixed in polypropylene. Processability of such thermoplastic blends as well as reactivity of the mixed components were followed by measuring energy, absorbed during the kneading of the melt. The vinylmonomer vinylmonomer - polyester additive, activated at higher temperature by the radiation-formed peroxy groups on the wood fiber, results in good processability of the thermoplastic blend, and gives interesting mechanical properties. Calandering, extrusion, pressmoulding and mechanical testing demonstrated good workability and practical value of the polypropylene composite material containing radiation-treated wood fiber. (author)

  12. Lattice imaging in melt crystallized polypropylene thin films

    Energy Technology Data Exchange (ETDEWEB)

    Plummer, C.J.G.; Gensler, R.; Kausch, H.H. [Ecole Polytechnique Federale, Lausanne (Switzerland). Dept. des Materiaux

    1997-11-01

    Melt crystallized isotactic polypropylene thin films of thickness between 30 and 100 nm have been investigated by high-resolution transmission electron microscopy at room temperature. The c-axis projection of the 2{sup *}3{sub 1} helices and their packing in the lattice were clearly visible in flat-on lamellae of the {alpha}-phase following reconstruction from the components of the image Fourier transform corresponding to the (110) and (040) lattice planes, and the image power spectra also indicated contributions from (130) and (060) reflections, corresponding to a line resolution of about 0.35 nm. These results are discussed in terms of Bloch wave calculations based on the generally accepted structure for the {alpha}-phase. Attempts to obtain lattice images of the {beta}-phase in isotactic polypropylene and melt crystallized syndiotactic polypropylene under similar operating conditions are also briefly discussed, although these provided relatively little structural information. (orig.) 44 refs.

  13. Gamma radiation resistance of tale-polypropylene composite materials

    International Nuclear Information System (INIS)

    Samples of isostatic polypropylene mixed with 10, 20 and 30 wt.% Talc were prepared. Sample films were gamma irradiated at 10 - 300 k Gy under air. The results from DSC suggested that fine particles of Talc showed pronounced nucleating effect by increasing the rate of crystallization and thermal stability. However, Talc-filled composites did not showed radiation resistant property. Absorbance intensity of carbonyl and hydroperoxide indicated the amount of oxidative degradation were increased with increasing radiation dose but would not depend on the Talc content. Talc was found to enhance polypropylene embrittlement and to lower the mechanical properties. However at appropriate concentration of Talc and low gamma dose. It is possible to improve the mechanical properties of the composites. In the field of environmental study, Talc-filled composites of iso tactic polypropylene may be used as a degradable plastic

  14. Radiation degradation of polypropylene molecular weight and melt viscosity change

    International Nuclear Information System (INIS)

    Isotactic polypropylene is widely used for the production of disposable syringes and for some other single-use medical products. Under irradiation the yield of degradation is significantly greater than the yield of crosslinking, resulting in a deterioration of mechanical properties. In addition, a slow process of chain autoxidative degradation is usually caused by irradiation. Two commercial resins and an additive free isotactic polypropylene were studied. The molecular weight distribution has been measured by high pressure, high temperature liquid chromatography in order to determine the immediate effect of radiation degradation. This was accompanied by melt viscosity measurements. The data may be useful for predicting the short and long term mechanical properties of polypropylene products sterilized by ionizing radiation. (author)

  15. [Effect of abrasion on three types of sutures in a metallic anchor].

    Science.gov (United States)

    Acosta Rodríguez, Eduardo; Almazán Díaz, Arturo

    2007-01-01

    It is necessary to slide the suture into the articulation in the arthroscopic techniques, this produce friction and abrasion of the suture, this is the principal cause of failure in the union of anchor-suture. We used a Fastak 2.4 anchor, Sawbones, No 2 Ethibond, No 2 Fiberwire and No 2 Herculine. Each suture was introduce to the anchor eyelet and was cycled in four times with 40N. The angles of traction were 0 degrees and 45 degrees at the same direction of the anchor eyelet and 45 degrees with different direction of the anchor eyelet. Five sutures were used in every test. We performed the Kolmogorov-Smirnof and "t" Student tests. In all the tests there were a significant differences. The strength of the suture is affected by the abrasion in the anchor eyelet. PMID:17937175

  16. Production of the oxidation-resistant polypropylene track membranes

    International Nuclear Information System (INIS)

    This paper describes results of the method of manufacturing the polypropylene track membranes produced by physicochemical treatment under irradiation of accelerated heavy ions of polymer films. The developed method allows to produce membranes 0.1 - 0.2 ?m in diameter and more with an improved structural and physicochemical properties. Poly-propylene track membranes of a novel sample are characterized by high homogeneity of pore sizes in magnitude, considerable mechanical strength, advanced thermal stability and resistance to oxidation in aggressive media. It opens new fields for their usage

  17. Investigation of thermal degradation of branched polypropylene via rheology

    Science.gov (United States)

    Drabek, Jiri; Zatloukal, Martin

    2015-04-01

    In this work, virgin as well as thermally degraded branched polypropylenes were investigated by using rotational and Sentmanat extensional rheometers. Based on the shear and extensional rheology data it was deduced that both chain scission and chain branching takes place during thermal degradation of the tested polypropylene. It was found that simple phenomenological constitutive equations such as Generalized Newtonian law and modified White Metzner model can be used to describe the measured steady state shear and uniaxial extensional viscosity data as well as for the simple quantification of the extensional strain hardening via their model parameters.

  18. Propriedades mecânicas de nanocompósitos de polipropileno e montmorilonita organofílica Mechanical properties of polypropylene and organophilic montmorillonite nanocomposites

    Directory of Open Access Journals (Sweden)

    Lucilene B. de Paiva

    2006-06-01

    Full Text Available Neste trabalho foram preparados nanocompósitos de polipropileno e montmorilonita organofílica comercial Cloisite 20A em concentrações de 2,5%, 5,0%, 7,5% e 10,0% e polipropileno graftizado com anidrido maleico como agente compatibilizante pela técnica de intercalação do fundido em extrusora de dupla rosca. Os materiais obtidos foram caracterizados por difração de raios x, ensaios de tração e impacto de acordo com as normas ASTM D638 e D256, respectivamente. Os resultados de difração de raios x indicaram a formação de nanocompósitos com estruturas parcialmente esfoliadas ou intercaladas, dependendo da composição, que proporcionaram aumento do módulo de elasticidade enquanto as propriedades de resistência ao impacto não foram satisfatórias.Nanocomposites of polypropylene and commercial montmorillonite organophilic Cloisite 20A containing 2.5%, 5%, 7.5% and 10% of clay with polypropylene-graft-maleic anhydride as coupling agent were prepared through the melt intercalation by twin-screw extruder. The materials were characterized by x-ray diffraction, tensile and impact properties according to ASTM D638 and D256 test methods, respectively. The x-ray diffraction results showed exfoliated or intercalated structures for different concentrations of the clay. The tensile modulus improved with the increase of the amount of the clay while the impact strength showed unsatisfactory results.

  19. Microbiology of Explanted Suture Segments from Infected and Noninfected Surgical Patients

    OpenAIRE

    Edmiston, Charles E.; Krepel, Candace J.; Marks, Richard M.; Rossi, Peter J.; Sanger, James; Goldblatt, Matthew; Graham, Mary Beth; Rothenburger, Stephen; Collier, John; Seabrook, Gary R.

    2013-01-01

    Sutures under selective host/environmental factors can potentiate postoperative surgical site infection (SSI). The present investigation characterized microbial recovery and biofilm formation from explanted absorbable (AB) and nonabsorbable (NAB) sutures from infected and noninfected sites. AB and NAB sutures were harvested from noninfected (70.9%) and infected (29.1%) sites in 158 patients. At explantation, devices were sonicated and processed for qualitative/quantitative bacteriology; selec...

  20. Tissue Reactions to Various Suture Materials Used in Oral Surgical Interventions

    OpenAIRE

    Romanos, Georgios E.; Khalid Al-Hezaimi; Fawad Javed; Mansour Al-Askar; Khalid Almas

    2012-01-01

    A variety of suture materials are available for primary wound closure following oral surgical procedures. The aim was to review the tissue reactions to the various suture materials used in oral surgical interventions. Databases were searched using the following keywords: cotton, nylon, polyglecaprone 25, polytetrafluoroethylene (ePTFE), Polyglactin 910, polyglycolic acid (PGA), polylactic acid, silk, surgery, suture, and tissue reaction. Articles published only in English language were includ...

  1. Modified Technique of Stapled Esophagojejunostomy Without a Purse-String Suture

    OpenAIRE

    Seshadri, Ramakrishnan Ayloor; Thammaiah, Siddappa K.; Vaidhyalingam, Venktesh

    2011-01-01

    Placement of a purse-string suture during a stapled esophagojejunostomy following total gastrectomy is a technically demanding and time consuming procedure. Improper placement of the purse-string suture can lead to anastamotic breakdown with its associated complications. We describe a technique of stapled esophagojejunostomy without using a purse-string suture. We used this technique in 35 patients including 4 patients who underwent an extended total gastrectomy. We encountered a difficulty o...

  2. Unidirectional barbed suture versus standard monofilament for urethrovesical anastomosis during robotic assisted laparoscopic radical prostatectomy

    OpenAIRE

    Marc Manganiello; Patrick Kenney; David Canes; Andrea Sorcini; Alireza Moinzadeh

    2012-01-01

    PURPOSE: V-LocTM180 (Covidien Healthcare, Mansfield, MA) is a new unidirectional barbed suture that may reduce loss of tension during a running closure. We evaluated the use of the barbed suture for urethrovesical anastomosis (UVA) during robotic assisted laparoscopic prostatectomy (RALP). Time to completion of UVA, post-operative anastomotic leak rate, and urinary incontinence were compared in patients undergoing UVA with 3-0 unidirectional-barbed suture vs. 3-0 MonocrylTM (Ethicon, Somervil...

  3. Gene Expression Changes Between Patent and Fused Cranial Sutures in a Nonsyndromic Craniosynostosis Population

    Science.gov (United States)

    Rhodes, Jennifer L.; Vega, Rafael A.; Ridder, Thomas; Shiang, Rita

    2015-01-01

    Objective: Craniosynostosis is a premature fusion of 1 or more cranial sutures. It may occur with additional morphological abnormalities (syndromic) or in isolation. Studies suggest that dysregulation of normal cell proliferation, differentiation, and migration has a role in isolated or nonsyndromic craniosynostosis but the molecular mechanisms remain unknown. The aim of this research is to identify genes differentially expressed in prematurely fused human suture compared to patent suture in nonsyndromic craniosynostosis. Methods: Bone fragments from synostosed and patent sutures of 7 infants with nonsyndromic craniosynostosis were collected during surgical release of fused sutures. RNA was isolated from the fragments (7 patent and 7 fused) and global gene expression profiled using the Illumina WGE-DASL assay and HumanRef 8.0 Beadchip. Results: Comparison of mRNA expression in fused and patent suture identified 68 genes significantly differentially expressed and having fold changes ? ?2.0 and ? 2.0 with a false discovery rate adjusted P value at .10 and 136 with adjusted P value of 0.15. SFRP2 (secreted frizzled-related protein 2) demonstrated the largest decrease in fused sutures. Analysis including only sagittal fused sutures revealed a set of 35 overlapping genes that may be involved in suture patency over all suture types. SPHKAP (sphingosine kinase type 1-interacting protein), a modulator of TGF? signaling, was significant in the sagittal subset. Conclusion: Differentially expressed genes were identified in fused suture relative to patent in a nonsyndromic craniosynostosis population. SFRP2 is likely important in suture patency. Genes having significant roles in osteoblastogenesis as negative regulators of canonical Wnt pathway were significantly downregulated.

  4. Follow up CT findings of suture granuloma in the chest wall: A case report

    International Nuclear Information System (INIS)

    Suture granuloma is a benign tumor defined by an inflammatory reaction and the formation of granuloma, which is caused by the reaction of a foreign body in regards to suture material after surgery. Recently, it has been reported as one of the rare complications following surgery, mainly in regards to non absorbable sutures. The authors hereby report a case along with CT findings and literature review for suture granuloma in the chest wall after lung lobectomy for lung cancer in a 65 year old woman

  5. Follow up CT findings of suture granuloma in the chest wall: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ka Eun; Lee, Young Kyung [Kyung Hee Univ. Hospital at Gangdong/School of Medicine/Kyung Hee Univ. Seoul, (Korea, Republic of); Sung, Dong Wook [Kyung Hee Univ. Hospital/School of Medicine/Kyung Hee Univ., Seoul, (Korea, Republic of)

    2012-09-15

    Suture granuloma is a benign tumor defined by an inflammatory reaction and the formation of granuloma, which is caused by the reaction of a foreign body in regards to suture material after surgery. Recently, it has been reported as one of the rare complications following surgery, mainly in regards to non absorbable sutures. The authors hereby report a case along with CT findings and literature review for suture granuloma in the chest wall after lung lobectomy for lung cancer in a 65 year old woman.

  6. Use of a new device for endoscopic suturing in the laparoscopic Burch procedure.

    Science.gov (United States)

    Gunn, G C; Cooper, R P; Gordon, N S; Gagnon, L

    1994-11-01

    An innovation in surgical instrumentation for performing endoscopic suturing was applied in 15 patients who underwent a laparoscopic approach to the traditional retropubic modified Burch procedure. PMID:9050535

  7. Evaluation of surgical implantation of electronic tags in European eel and effects of different suture materials

    DEFF Research Database (Denmark)

    Thorstad, Eva B.; Økland, Finn

    2013-01-01

    Effects of implanting data-storage tags in European eel, Anguilla anguilla, and the suitability of different suture materials (braided permanent silk, permanent monofilament, absorbable and absorbable antibacterial) were examined. The tags consisted of an electronic unit and three floats on a wire, making them flexible and able to follow the swimming movements of the eel. No mortality occurred, and tagged fish did not differ from the control fish in growth. Sutures were shed or dissolved slowly. After 4 weeks, there was no difference among the groups in the proportion of sutures left. After 6 months, fish with braided silk had largely shed their sutures, fish with monofilament sutures had the majority of sutures left, whereas the fish with absorbable sutures were intermediate in between. Fish with monofilament sutures showed the least-extensive inflammation reactions and fastest wound healing. Antibacterial treatment had no effect on inflammation or healing rates. After 6 months, the tag started to become expelled through the incision in five fish (12%). The internal reaction appeared stronger around the floats, suggesting that the coating material of the floats created a tissue reaction, which should be further investigated. Intraperitoneal implantation appears to be a suitable tagging method for European silver eel, and it is recommended to close incisions using permanent monofilament sutures

  8. A Comparative In Vivo Study of Tissue Reactions to Four Suturing Materials

    Directory of Open Access Journals (Sweden)

    Shahla Kakoei

    2010-06-01

    Full Text Available INTRODUCTION: The purpose of this study was to compare the histopathologic reaction of four suturing materials: silk, polyvinylidene fluoride (PVDF, polyglycolic acid, and catgut in the oral mucosa of albino rabbits. MATERIALS AND METHODS: The twenty-one male mature albino rabbits which were used in this study were randomly divided into three groups of seven each. Silk, PVDF, polyglycolic acid and catgut suture materials were tested in the oral mucosa of these animals. The animals were sacrificed 2, 4, and 7 days after suturing. Two pathologists evaluated the samples by determining the presence and level of inflammation, granulation tissue, and fibrosis formation. Data were statistically analyzed by Kruskal Wallis and Mann-Whitney U tests. RESULTS: Histological features of the samples showed that PVDF and plain catgut suture materials produced more fibrous tissue (favorable response on the fourth day in comparison with silk suture (P=0.02. Also, in the 7-day samples PVDF sutures produced the mildest inflammation when compared with the silk sutures (P=0.015. CONCLUSION: According to the results of this study, it can be convey that PVDF suture materials created mild tissue reactions and can be a reasonable candidate for suturing oral tissues.

  9. Extrusion of bone anchor suture following flexor digitorum profundus tendon avulsion injury repair.

    LENUS (Irish Health Repository)

    Tiong, William H C

    2011-09-01

    Flexor digitorum profundus (FDP) zone I tendon avulsion injury is traditionally repaired with a pullout suture technique. More recently, bone anchor sutures have been used as a viable alternative and have largely replaced areas in hand surgery where pullout suture technique was once required. To date, there have been very few complications reported related to bone anchor suture use in FDP tendon reattachment to the bone. We report a very unusual case of extrusion of bone anchor through the nailbed, 6 years after zone I FDP tendon avulsion injury repair and a brief review of literature.

  10. Evaluation of polypropylene/saw dust composites prepared with maleated polypropylene (mapp) produced by reactive extrusion

    Scientific Electronic Library Online (English)

    Ernani, Trombetta; Thais, Flores-Sahagun; Kestur G., Satyanarayana.

    Full Text Available Considering the importance of the environment and fuel economy, the Brazilian automotive industry has focused on the development of lightweight materials based on renewable resources. Replacement of PP- talc composite by PP- saw dust composite is a promising possibility. This paper presents the prep [...] aration of maleated polypropylene (MAPP) through reactive extrusion using different amounts of peroxides and maleic anhydride as well its characterization. Using 20% of saw dust coated with different amounts of prepared MAPP, several composites were prepared including one with commercial MAPP. Injection molded samples of all these composites along with that without the compatibilizer were characterized for mechanical properties. These studies indicated fulfilling the proposed objectives: (i) finding the optimal reactive extrusion conditions to prepare MAPP samples; (ii) preparation of PP/saw dust composites with and without MAPP coating; (iii) to arrive at optimized composite to get the best performance through their characterization for various properties of all the produced composites.

  11. Surface modification of polypropylene and compatibilization of interfaces in incompatible blends of polypropylene with polystyrene by plasma of CO2

    International Nuclear Information System (INIS)

    The effect of surface modification of polypropylene (PP) film is induced by CO2 plasma in this study. The change in chemical structures on the surface of PP film is characterized by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR). The polarity of modified surface of PP film is investigated by contact angle method. The compatibilization of interfaces between polypropylene and polystyrene phases in incompatible blends is studied by the treatment of plasma of CO2. Transition layer thickness is measured by small angle light scattering (SALS).

  12. Effect of hot drawing process on physical and thermal properties of polypropylene fiber containing selective peroxide and comparison with conventional polypropylene fibers

    Directory of Open Access Journals (Sweden)

    Bahareh Kalantari

    2012-01-01

    Full Text Available In this research, the effect of the drawing process on the physical and thermal properties of commercially available polypropylene fiber containing selective peroxide was studied. Attempts have also been made to compare this drawn fiber sample with conventional polypropylene fibers produced from reactor and with controlled rheology grades. The results showed that the drawn PP/Peroxide fiber has higher birefringence, tenacity, and initial modulus compared with that of the drawn polypropylene fiber. Moreover, the fraction of load carrying chains in various drawn polypropylene fibers was evaluated on the basis of simplified models.

  13. Iris mattress suture: a technique for sectoral iris defect repair.

    Science.gov (United States)

    Tsao, Sean W; Holz, Huck A

    2015-03-01

    Achieving a cosmetic and functional outcome from iris defect repair is a surgical challenge. We describe an adaptation of techniques to address a case of 2.5 clock hours of sectoral iris tissue defect. Our method combines Siepser's modified closed-chamber sliding knot technique with the placement of a double-armed iris mattress suture to approximate iris tissue to the scleral wall and thereby create a pseudo-iris root. This technique reduces glare and achieves a cosmetic outcome for the patient. PMID:24879808

  14. Surgical technique for optimal outcomes: Part II. Repairing tissue: suturing.

    Science.gov (United States)

    Miller, Christopher J; Antunes, Marcelo B; Sobanko, Joseph F

    2015-03-01

    Sound surgical technique is necessary to achieve excellent surgical outcomes. Despite the fact that dermatologists perform more office-based cutaneous surgery than any other specialty, few dermatologists have opportunities for practical instruction to improve surgical technique after residency and fellowship. This 2-part continuing medical education article will address key principles of surgical technique at each step of cutaneous reconstruction. Part II reviews the placement of deep and superficial sutures. Objective quality control questions are proposed to provide a framework for self-assessment and continuous quality improvement. PMID:25687310

  15. CRUDE PALM OIL AS A BIOADDITIVE IN POLYPROPYLENE BLOWN FILMS

    Directory of Open Access Journals (Sweden)

    Emiliana Rose Jusoh,

    2012-01-01

    Full Text Available Growing public concern about environment and potential risks to health in the polymer and plasticizer industry promises to increase the market for a safer alternative plasticizer such as a vegetable oil-based agent. The purpose of this study was to investigate the potential of crude palm oil as a bio-additive in polypropylene blown films. The polypropylene was blended with 1%, 3%, and 5% dosages of CPO using a twin screw extruder. The extruded samples were blown using the blown thin film technique. Mechanical, physical, and morphological properties were characterized. Modifying polypropylene with CPO showed good enhancement in the mechanical properties of the polypropylene. Tensile strength, elongation at break, impact strength, and tear strength all increased. The scanning electron microscopy photographs of the CPO-modified PP clearly supported the results from the mechanical strength tests. The presence of CPO in the PP matrices decreased the density and increased the melt flow rate. These findings contribute new knowledge to the additives area and give important implications for designing and manufacturing polymer packaging materials.

  16. Rheological behaviour of metallocene polypropylenes prepared by reactive extrusion process.

    Czech Academy of Sciences Publication Activity Database

    Pivokonský, Radek; Filip, Petr; Zatloukal, M.; Tzoganakis, C.

    Lisbon : European Society of Rheology, 2012. s. 394. [International Congress on Rheology /16./. 05.08.2012-10.08.2012, Lisbon] R&D Projects: GA ?R GA103/09/2066 Keywords : metallocene polypropylene * constitutive modelling * differential models Subject RIV: BK - Fluid Dynamics

  17. Polypropylene nanocomposites: effect of coupling agent on structure and properties.

    Czech Academy of Sciences Publication Activity Database

    Kotek, Ji?í; Kelnar, Ivan; Studenovský, Martin

    Dresden : Max Planck Institute for the Physic of Complex Systems, 2005. [MPG-MOEL– Symposium: Science and Art in Europe, Polymers: Materials in Nature and in Advanced Technologies. 23.5.2005-25.5.2005, Dresden] R&D Projects: GA AV ?R(CZ) IBS4050351 Keywords : polypropylene * nanocomposites * melt-compounding Subject RIV: CD - Macromolecular Chemistry

  18. Investigations of intensively deformed polypropylene fibres by positron annihilation

    Energy Technology Data Exchange (ETDEWEB)

    Zaslavskij, B.I.; Tatur, A.O.; Santarovic, V.P.; Kuznecov, Ju.A.; Zelenev, Ju.V.; Budnickij, G.A. (Moskovskij Tekstil' nyj Inst. (USSR))

    1985-04-01

    The spectra of positron annihilation and the direction correlation of the annihilation radiation of deformed polypropylene hollow fibres were recorded in vacuum, air and oxygen. The results indicate the formation of large pores by the action of oxygen in the deformed fibres.

  19. Investigations of intensively deformed polypropylene fibres by positron annihilation

    International Nuclear Information System (INIS)

    The spectra of positron annihilation and the direction correlation of the annihilation radiation of deformed polypropylene hollow fibres were recorded in vacuum, air and oxygen. The results indicate the formation of large pores by the action of oxygen in the deformed fibres. (author)

  20. Mechanical properties of polypropylene/cycloolefin copolymer blends.

    Czech Academy of Sciences Publication Activity Database

    Vacková, Ta?ana; Šlouf, Miroslav

    Istanbul : Polymer Processing Society, 2010. s. 144. [Polymer Processing Society Regional Meeting PPS -26. 20.10.2010-23.10.2010, Istanbul] R&D Projects: GA ?R GP106/09/P272 Institutional research plan: CEZ:AV0Z40500505 Keywords : polymer blends * polypropylene * cycloolefin copolymer Subject RIV: JI - Composite Materials

  1. Effects of gamma irradiation on the physical properties of laminated packaging materials. 2. polypropylene-polypropylene, polypropylene-polyethylene, and polyester-polyethylene

    International Nuclear Information System (INIS)

    This experiment was done to determine the effects of irradiation on the physical properties of three kinds of laminated packaging materials, i.e. polypropylene-polypropylene, polypropylene-polyethylene, polyester-polyethylene. Observations were made on pinhole production, leakage, oil resistance, resistance against insect penetration, colour, odour tensile strength, elongation at break, seal strength and tear resistance. The samples were irradiated with doses of 0, 5 and 10 kGy, then stored at room temperature and examined after 0, 3, 6 and 12 months of storage. The results showed that irradiation doses up to 10 kGy, as well as storage up to 12 months, did not create pinholes, or leakage in pouches prepared from laminated films. The resistance of the films to oil and insect penetration, the colour, and the odour were also unchanged. Both irradiation and storage treatments had a significant effect on physical properties of the laminated films. In general, the changes started to be significant after 6 months' storage either in unirradiated samples or in irradiated ones. It could be concluded that irradiation with doses up to 10 kGy had no meaningful effect on the physical strength of the laminated films, therefore such films could be used as packaging materials for irradiated foods. (author)

  2. Treatment of functional ventricular fold phonation by temporary suture lateralization.

    Science.gov (United States)

    Friedrich, Gerhard; Kiesler, Karl; Gugatschka, Markus

    2010-09-01

    Ventricular fold phonation (VFP) is a phenomenon characterized by phonation using the false vocal folds. Besides a substitution voice due to loss of the true vocal folds-so called compensatory type-the noncompensatory types have a psychogenic, functional, or habitual background. Therapeutic options for these cases so far comprise voice therapy, pharmacological therapy (injection of anesthetics or botulinum toxin), and, in case of failure, surgical resection of the ventricular folds. Indication for aggressive surgical interventions is usually difficult, as there is always a risk of producing an irreversible state with an even worse situation. We present two cases of functional (psychogenic) VFP treatment refractory to conservative treatment. Lateralization of the ventricular folds by an endo-extralaryngeal temporary suture, similar to that used in bilateral vocal fold paralysis, was performed. Immediately after the procedure, a constant phonation at glottic level could be achieved in both cases. Sutures were removed 4 days after surgery, and phonation remained at the glottic level. Vocal fold phonation could be stabilized in the long run, and both patients recovered completely under additional voice therapy. PMID:19853409

  3. An experimental model to retraining in microvascular suture

    Scientific Electronic Library Online (English)

    Marcos Ricardo de Oliveira, Jaeger; Pedro Bins, Ely; Jefferson André, Pires; Lydia Masako, Ferreira.

    Full Text Available PURPOSE: To demonstrate an experimental model of up to four hours a week of independent study that allows relearning in microvascular sutures. METHODS: Wistar rats between 200 and 500 grams surplus research experiments were used. Femoral vessels are covered on one or both sides through a groin i [...] ncision obliquely along the inguinal ligament. Femoral artery and vein are isolated and measured being clamped and cut. The individual performs in microvascular anastomosis complexity arterial and venous terminoterminal sequence. terminolateral and venous and arterial grafts in vessels. Permeability is evaluated by testing vascular patency after creation of microvascular anastomosis. RESULTS: In the first specimen, only arterial and venous vascular anastomosis are performed terminoterminal. The average diameter of the femoral veins varies from 0.8 to 2 mm between rodents (artery, between 0.6 and 1.4 mm, between 0.8 and 2 mm vein). The superficiality of the vessels allows faster dissection, may also be held in other inguinal region. CONCLUSION: The model of individual retraining allows learning microvascular suture in individuals of permanent staff.

  4. Sutural loosening and skeletal flexibility during growth: determination of drop-like shapes in sea urchins.

    Science.gov (United States)

    Johnson, Amy S; Ellers, Olaf; Lemire, Jim; Minor, Melissa; Leddy, Holly A

    2002-02-01

    The shape of sea urchins may be determined mechanically by patterns of force analogous to those that determine the shape of a water droplet. This mechanical analogy implies skeletal flexibility at the time of growth. Although comprised of many rigid calcite plates, sutural collagenous ligaments could confer such flexibility if the sutures between plates loosened and acted as joints at the time of growth. We present experimental evidence of such flexibility associated with weight gain and growth. Over 13-, 4-, and 2-week periods, fed urchins (Strongylocentrotus droebachiensis) gained weight and developed looser sutures than unfed urchins that maintained or lost weight. Further, skeletons of fed urchins force-relaxed more than did those of unfed urchins and urchins with loose sutures force-relaxed more than those with tight sutures. Urchins (Strongylocentrotus franciscanus) fed for two and a half weeks, gained weight, also had looser skeletons and deposited calcite at sutural margins, whereas unfed ones did not. In field populations of S. droebachiensis the percentage having loose sutures varied with urchin diameter and reflected their size-specific growth rate. The association between feeding, weight gain, calcite deposition, force relaxation and sutural looseness supports the hypothesis that urchins deform flexibly while growing, thus determining their drop-like shapes. PMID:11839189

  5. Thermal Characterizations of Silver-containing Bioactive Glass-coated Sutures

    OpenAIRE

    Blaker, Jonny J.; Boccaccini, Aldo R.; Nazhat, Showan N.

    2005-01-01

    Abstract This study utilized and compared a number of thermal analysis methods to characterize the thermal properties of commercial sutures with and without antimicrobial coatings of silver-doped bioactive glass (AgBG) interlocking particulates. The effect of a slurry dipping technique used to coat resorbable Vicryl® (polyglactin 910) and non-resorbable Mersilk® surgical sutures with AgBG was investigated...

  6. Absorbable Versus Silk Sutures for Surgical Treatment of Trachomatous Trichiasis in Ethiopia: A Randomised Controlled Trial

    OpenAIRE

    Rajak, S. N.; Habtamu, E.; Weiss, H. A.; Kello, A. B.; Gebre, T.; Genet, A.; Bailey, R. L.; Mabey, D. C.; Khaw, P. T.; Gilbert, C. E.; Emerson, P. M.; Burton, M. J.

    2011-01-01

    Trachoma causes blindness through an anatomical abnormality called trichiasis (lashes touching the eye). Trichiasis can recur after corrective surgery. We tested the hypothesis that using absorbable sutures instead of silk sutures might reduce the risk of recurrent disease among patients with major trichiasis in a randomised trial.

  7. Effect of gamma irradiation on the enzymatic degradation of polyglycolic acid absorbable sutures

    International Nuclear Information System (INIS)

    The effect of gamma irradiation on the enzymatic as well as the in vivo degradation of polyglycolic acid sutures was examined. The sutures of size 2-0 were irradiated at dosage levels of 0-20 mrad. The three enzymes chosen for this study were esterase, alpha-chymotrypsin, and trypsin. The irradiated sutures were both immersed in the enzyme solutions; their corresponding buffer controls, and implanted in inbred black-and-white hooded hister rats (Liverpool strain). The degradation of PGA sutures was determined mechanically. Among the three enzymes studied, esterase showed the highest enzymatic effect on the degradation of the unirradiated and irradiated PGA sutures. Trypsin's effect on PGA sutures was not observed until 20 mrad. The findings of trypsin demonstrated the hypothesis that synthetic high molecular weight polymers, which are initially resistant to enzymatic degradation, could become prone to enzymatic attack after altering their physical and chemical structures. Implanted PGA sutures maintained a similar or slightly higher mean tensile breaking strength in in vivo degradation compared to in vitro degradation (0.1M tris buffer of pH . 7.5); these degradation profiles suggest that PGA does not display similar behavior in in vivo and in vitro degradations. The magnitude of dissimilarity depends on the radiation dosage and on the duration of degradation, and is speculated to be attributable to the specific action of enzymes with respect to the configuration and mes with respect to the configuration and chemical structure of the PGA sutures

  8. Arthroscopic repair of peripheral triangular fibrocartilage complex tears with suture welding: a technical report.

    Science.gov (United States)

    Badia, Alejandro; Jiménez, Alexis

    2006-10-01

    This report presents a method of arthroscopic repair of the peripheral triangular fibrocartilage complex tears that replaces traditional suture knots with ultrasonic welding of sutures. This will help eliminate potential causes of ulnar-sided wrist discomfort during the postoperative period. PMID:17027791

  9. Skin closure using staples and nylon sutures: a comparison of results.

    OpenAIRE

    Stockley, I.; Elson, R. A.

    1987-01-01

    A disposable skin stapler (Elite: Auto Suture UK Ltd) and Nylon vertical mattress sutures have been used for skin closure. The complications related to each method were evaluated in 129 wounds. There was a higher incidence of inflammation, discomfort on removal and spreading of the healing scar associated with staples. The only advantage of staples was speed of wound closure.

  10. STUDY OF SKIN STAPLES AND CONVENTIONAL SUTURE FOR ABDOMINAL SKIN WOUND CLOSURE

    Directory of Open Access Journals (Sweden)

    Avinash K. Bhavikatti

    2012-08-01

    Full Text Available

    Introduction: The use of automatic stapling device for skin closure has become more popular due to its minimum disadvantages as compared to conventional suturing. Hence, this study was undertaken to compare the time required for abdominal skin closure and pain during suture removal, between skin staplers and conventional suture.

    Materials and Methods: The study includes 100 patients with age group of 45yrs-75yrs  undergoing elective surgery, of which 50 patients  underwent wound closure by staplers (Group-I and 50 patients underwent closure using  prolene suturing (Group-II, during June 2009 to June 2011 at Basaweshwar Teaching and General Hospital, Gulbarga. Patients were randomly selected for conventional suture and skin staple. Time duration for wound closure was recorded and pain scoring was given during suture removal, between both groups.

    Results and conclusion: In our study duration of wound closure was statistically significant (P<0.001 with staplers requiring lesser time than conventional prolene sutures, we also found that pain during suture removal between both groups was statistically significant (P<0.001. We believe the advantages of speed and convenience of skin staples outweigh the extra cost, provided the disposable instruments are reused until empty.

  11. Fibroblast growth factors lead to increased Msx2 expression and fusion in calvarial sutures.

    Science.gov (United States)

    Ignelzi, Michael A; Wang, Wei; Young, Andrew T

    2003-04-01

    Craniosynostosis, the premature fusion of the skull bones at the sutures, represents a disruption to the coordinated growth and development of the expanding brain and calvarial vault and is the second most common birth defect that affects the craniofacial complex. Mutations in the human homeobox-containing gene, Msx2, have been shown to cause Boston type craniosynostosis, and we have shown that overexpression of Msx2 leads to craniosynostosis in mice. Activating mutations in fibroblast growth factor (FGF) receptors are thought to cause craniosynostosis in Crouzon, Apert, Jackson-Weiss, Beare-Stevenson, and Muenke syndromes. To mimic activated signaling by mutated FGF receptors, we used heparin acrylic beads to deliver FGF ligands to mouse calvaria and demonstrated increased Msx2, Runx2, Bsp, and Osteocalcin gene expression, decreased cell proliferation, and suture obliteration and fusion. FGF2 elicited the greatest increase in Msx2 expression, and FGF1 was most likely to cause suture obliteration and fusion. Of the three sutures studied, the coronal suture exhibited the greatest increase in Msx2 expression and was the most likely to undergo obliteration and fusion. These results are intriguing because the coronal suture is the most commonly affected suture in syndromic craniosynostosis. These results suggest that Msx2 is a downstream target of FGF receptor signaling and that increased FGF signaling leads to osteogenic differentiation by sutural mesenchyme in mouse calvaria. These results are consistent with the hypotheses that increased Msx2 expression and activated signaling by mutated FGF receptors lead to craniosynostosis. PMID:12674336

  12. SR and LR Union Suture for the Treatment of Myopic Strabismus Fixus: Is Scleral Fixation Necessary?

    Science.gov (United States)

    Lam, Carol P. S.; Yam, Jason C. S.; Lau, Flora H. S.; Fan, Dorothy S. P.; Wong, C. Y.; Yu, Christopher B. O.; Lau, Winnie W. Y.

    2015-01-01

    Purpose. To evaluate and compare the effectiveness of scleral fixation SR and LR union suture and nonscleral fixation union suture for the treatment of myopic strabismus fixus. Methods. Retrospective review of 32 eyes of 22 patients with myopic strabismus fixus who had undergone union suture of superior rectus (SR) and lateral rectus (LR) with or without scleral fixation, and follow-up longer than 6 months at Hong Kong Eye Hospital from 2006 to 2013. Surgical techniques and outcomes in terms of ocular alignment are analyzed. Results. There is significant overall improvement both in postoperative angle of esodeviation (P 0.05). Conclusions. Union suture of SR and LR is an effective procedure in correcting myopic strabismus fixus. Fixation of the union suture to the sclera does not improve surgical outcome. PMID:25954751

  13. Development of foams from linear polypropylene (PP) and high melt strength polypropylene (HMSPP) polymeric blends

    International Nuclear Information System (INIS)

    Foamed polymers are future materials, with a comprehensive application field. They can be used in order to improve appearance of insulation structures, for example, or to reduce costs involving materials. This work address to Isotactic Polypropylene / High Melt Strength Polypropylene blends, for foams production. Rheological behavior of polymer melt, especially referring to viscosity in processing temperature, plays a decisive role in applications where dominates extensional flow, as in case of foaming. If the viscosity is very low, it will correspond to a low melt strength, as in case of linear homopolymer (Isotact PP), and the foam will be prejudiced, due to the impossibility of expansion. Otherwise, if the viscosity is very high, with a high melt strength, the foam will collapse immediately after its formation. In order to get foams with an homogeneous and defined cellular structure, there were accomplished blends, 50% in weight, between linear homopolymer (isotactic PP) and HMSPP, from PP modified as per gamma radiation, in acetylene environment and at a 12.5 kGy doses. Extrusion process used a soluble foaming methodology, according to a processing/dissolution principle, which involves the dissolution of a Physical Blowing Agent (PBA), under 30 bar pressure, homogeneously mixed with polymeric melt. Extrusion conditions, that generally involve temperature, pressure and viscoelastic material flow control were experimentally investigated to define prevalent characteristics for producing foams. Nitrogen was the used PBA and process extrusion parameters were adapted to PP, HMSPP and their 50% in weight mixtures thereof. Major PP and HMSPP characteristics were obtained via melt Index and melt strength and thermal analyses (DSC/TGA), in order to make viable and to reproduce foaming as per extrusion process. Foams cellular morphology of PP, HMSPP and their 50% in weight mixtures thereof was investigated, with and without talc addition, as nucleating agent, by using Scanning Electron Microscope (SEM). Micrographs obtained pointed to closed cells foams, in which the pressure is kept during all cell formation stage, informing that closed cells foams are used in thermal insulation in Civil Construction and in thermal vials. Density analyses accomplished in foams produced in our work showed typical results for high density foams (320 to 800 kg/m3 range), around 500 kg/m3, used for wire and cables and for structural purposes (structural foams), by replacing wood, metals or solid plastics. Structural foams have high density (above 320 kg/m3) and cellular structures are specially composed by holes. (author)

  14. End-on extramucosal single layer suture with double anchoring in the submucosa on rabbits

    Directory of Open Access Journals (Sweden)

    Nascimento Luiz Roberto do

    1999-01-01

    Full Text Available The techniques of gastrointestinal surgical sutures have been frequently focused in controversial publications. These ones concern not only anastomosis? types but also about thread types and how to apply them. The values of the submucosa as layer of greatest resistence of the digestive tube was already known since the past century. The aim of this study is to avaluate the suture in an extramucosal single-layer suture with double anchoring of the submucosa, a technical detail not found in the searched literature. This experiment was carried out using 36 white,male adults New Zealand, rabbits divided into three groups which differed only regarding day of re-operation and euthanasia, as followed: group I ( 4 days, group II (7 days and group III ( 15 days. Two transversal and parallel gastrotomies were perfomed in the same animal, one distal and other proximal, of with 4 cm extension each. In these gastrotomies two types of sutures were alternated : 1- End-on extramucosal single-layer suture and 2- End-on extramucosal single-layer suture, with double anchoring in the submucosa. Macroscopic and microscopic studies were perfomed on the suture line in both gastrotomies and in each period of euthanasia. Except for the serosa item whose results were similar for both sutures, statiscally, the extramucosal single-layer suture, with double anchoring of submucosa layer showed better macro and microscopic results than the extramucosal single-layer suture in group I (4 days. In the others periods of euthanasia (groups II and III, the statistical results were similar.

  15. Transcutaneous Serdev Suture For Buttock’s Lift

    Directory of Open Access Journals (Sweden)

    Nikolay Serdev

    2013-10-01

    Full Text Available This article presents the author's technique and experience in the treatment of the flaccid "unhappy buttock" form with his surgical procedure of buttock lift by suture, without incision scars. The author first presented this new operation technique on a national level at the 2nd Annual Meeting of the National Bulgarian Society for Aesthetic Surgery and Aesthetic Medicine in Sofia on March 18, 1994 [1] and internationally at many scientific meetings over the world [2, 3, 4…]. The result is a visual change in the buttock position to a higher one, which elongates the lower limbs and changes the proportions between lower and upper half of the body. The aim of this study is to describe a mini-invasive procedure of beautification of the buttock form without scars by creating a lifting effect on the buttock's subcutaneous tissue, using a suture that takes the inferiorly positioned deep fibrose tissue and fixes it upwards to the sacro-cutaneous fascia, discovered by the author. Aesthetic and technical considerations required properly sculpting the buttocks into a higher position, demonstrating nicely rounded form. Preoperative shape is discussed and patient evaluations, operative techniques, postoperative management and results after 4 years of experience are emphasized. 1032 female patients, and 26 male patients aged 18-62 years, with ptosis and cellulite on the buttocks were treated since 1993 on an outpatient basis by the "Serdev suture technique without visible scars". Important instrumentarium is a long, curved, elastic needle and Polycon semi-elastic Bulgarian antimicrobial polycaproamide long term (in 2 years absorbable surgical threads Polycon, produced in Bulgaria. This operation has been performed either alone or after ultrasonic assisted liposculpture (UAL that reduces the amount of fat and heaviness. All patients reported a high degree of satisfaction. A stable improvement in the buttock position and form was observed for the period described. In the postoperative period the complication rate was minimal and resolved in the first 4-5 days post operative period. The skin puncture in the perianal zone makes antibiotic prophylaxis obligatory as well as a strict follow up for the first 7 days. Some pain in the sitting position was observed for at least 5 to 10 days, but all other social and professional duties and activities were possible. This outpatient procedure is effective in the correction of buttock laxity and ptosis and creates a new form, universally accepted as "happy buttocks".

  16. Tibetan Apples and Oranges: Surficial Sutures and Overlapping Lithospheres

    Science.gov (United States)

    Chen, W. P.; Hung, S. H.; Wang, C. Y.; Tseng, T. L.

    2014-12-01

    Multi-scale, finite-frequency tomography across the Himalayas-Tibet shows a clear, subhorizontal anomaly of high VP and VSin the upper mantle that can be traced from under N. India all the way to beneath central Tibet. This configuration of the "Greater India" (GI), or the submerged, northern portion of the Indian shield, is combined with other constraints to reconstruct position of the Indian lithospheric mantle (ILM) relative to Asia back to about 15 Ma ago, or the onset of the latest magmatic activity in Tibet. By then, the leading edge of the ILM (Indian mantle front, IMF) has advanced subhorizontally past the entire Lhasa terrane and also probably have caused the lithospheric mantle beneath the Qiangtang terrane to thicken. The thickening is likely to have led to Rayleigh-Taylor instability, causing widespread but small volume of magmatic activity in northern Tibet. Meanwhile, the detached lithospheric mantle foundered through the upper mantle to rest at the bottom of the mantle transition zone (MTZ), just above the lower mantle. This detached lithospheric mantle manifests itself as a large-scale seismic anomaly of high compressional wave speed (VP) but curiously is undetectable through shear-waves. Based on laboratory data for nominally anhydrous olivine and its high-pressure polymorphs (NAO), the discordant results between P- and S-waves is explained by abundant hydroxyls in the foundered lithospheric mantle, a hypothesis supported by other evidences as well. Since NAO can hold ~1 wt% of water throughout the upper mantle and the MTZ, foundering of thickened lithospheric mantle caused by continental collision is an under-appreciated but effective pathway for water to enter the deep mantle. Currently, the Indus-Yarlung suture between northern India and the Lhasa terrane appears to be an inactive, crustal feature, as the GI continues to pass beneath it. On the other hand, even though the IMF has now advanced northward beyond the Bangong-Nujiang suture (BNS), which marks the suture between the Lhasa (southern Tibet) and the Qiangtang terranes (central Tibet) in the Mesozoic, the BNS seems to have been a zone of deformation over lithospheric scale when the IMF interacted with the Qiangtang lithosphere about 15 Ma ago. Indeed the Moho around this zone is highly disturbed, a feature not found elsewhere under Tibet.

  17. Celastrol nanoparticles inhibit corneal neovascularization induced by suturing in rats

    Directory of Open Access Journals (Sweden)

    Li ZR

    2012-03-01

    Full Text Available Zhanrong Li1, Lin Yao1, Jingguo Li2, Wenxin Zhang1, Xianghua Wu1, Yi Liu1, Miaoli Lin1, Wenru Su1, Yongping Li1, Dan Liang11State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, 2School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou, People's Republic of ChinaPurpose: Celastrol, a traditional Chinese medicine, is widely used in anti-inflammation and anti-angiogenesis research. However, the poor water solubility of celastrol restricts its further application. This paper aims to study the effect of celastrol nanoparticles (CNPs on corneal neovascularization (CNV and determine the possible mechanism.Methods: To improve the hydrophilicity of celastrol, celastrol-loaded poly(ethylene glycol-block-poly(?-caprolactone nanopolymeric micelles were developed. The characterization of CNPs was measured by dynamic light scattering and transmission electron microscopy analysis. Celastrol loading content and release were assessed by ultraviolet-visible analysis and high performance liquid chromatography, respectively. In vitro, human umbilical vein endothelial cell proliferation and capillary-like tube formation were assayed. In vivo, suture-induced CNV was chosen to evaluate the effect of CNPs on CNV in rats. Immunohistochemistry for CD68 assessed the macrophage infiltration of the cornea on day 6 after surgery. Real-time quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay were used to evaluate the messenger ribonucleic acid and protein levels, respectively, of vascular endothelial growth factor, matrix metalloproteinase 9, and monocyte chemoattractant protein 1 in the cornea.Results: The mean diameter of CNPs with spherical shape was 48 nm. The celastrol loading content was 7.36%. The release behavior of CNPs in buffered solution (pH 7.4 showed a typical two-phase release profile. CNPs inhibited the proliferation of human umbilical vein endothelial cells in a dose-independent manner and suppressed the capillary structure formation. After treatment with CNPs, the length and area of CNV reduced from 1.16 ± 0.18 mm to 0.49 ± 0.12 mm and from 7.71 ± 0.94 mm2 to 2.29 ± 0.61 mm2, respectively. Macrophage infiltration decreased significantly in the CNP-treated corneas. CNPs reduced the expression of vascular endothelial growth factor, matrix metalloproteinase 9, and monocyte chemoattractant protein 1 in the cornea on day 6 after suturing.Conclusion: CNPs significantly inhibited suture-induced CNV by suppressing macrophage infiltration and the expression of vascular endothelial growth factor and matrix metalloproteinase 9 in the rat cornea.Keywords: celastrol, PEG-b-PCL nanopolymeric micelles, corneal neovascularization, macrophages, VEGF, MMP-9

  18. Effect of maleated polypropylene emulsion on the mechanical and thermal properties of lignin-polypropylene blends

    Science.gov (United States)

    Abdelwahab, Mohamed; Misra, Manjusri; Mohanty, Amar

    2015-05-01

    The increasing oil rates and environmental concerns of the use of synthetic or petroleum-based polymers has newly led to a growing attention in eco-friendly materials. Lignin has received much attention as a novel eco-friendly material due to its abundant availability and its potential as a low-cost filler. Biobased blends from polypropylene (PP) and lignin were fabricated by extrusion followed by injection moulding. In order to improve the compatibility of the polar lignin and the non-polar matrix PP, three different maleated PP emulsions, namely ME91735 (nonionic PP emulsion), ME42035 (cationic water based emulsion of polyolefin waxes) and PP286 (containing 1-5% N,N-ethylethanolamine) were used as coupling agents. The mechanical properties such as tensile and flexural strength as well as tensile and flexural modulus of the blends were improved by using lignin treated with 2.5 wt.% of the emulsions. However, the elongation at break decreased in the case of the lignin treated with ME91735 and ME42035 as compared to the untreated lignin. The morphological and thermal properties of the blends were also studied.

  19. Application analysis on different suture of scleral flap in trabeculectomy

    Directory of Open Access Journals (Sweden)

    Ning Liu

    2014-05-01

    Full Text Available AIM: To research the application of scleral flap suture in trabeculectomy. METHODS: Totally 114 primary angle-closure glaucoma patients, aged from 36-72 years old, were selected as the objects, and randomly divided into research group and control group. The two groups received different administration methods. Traditional sewing method of sclera flap was used in research group and improved sewing method of sclera flap was used in control group. RESULTS: There was statistical differences between postoperative intraocular pressure of the patients in the observation group and the control group after 1d; 2wk; 1, 3mo(PPP>0.05.CONCLUSION: It is safe and effective that the improved sewing method of sclera flap for trabeculectomy of acute angle-closure glaucoma, and it is a better method to avoid the occurrence of shallow anterior chamber than the traditional sewing method in the early stage after operation.

  20. Single-incision laparoscopic splenectomy with innovative gastric traction suture

    Directory of Open Access Journals (Sweden)

    Srikanth G

    2011-01-01

    Full Text Available Laparoscopic splenectomy is now the gold standard for patients with idiopathic thrombocytopenic purpura (ITP undergoing splenectomy. There are a few reports in literature on single-incision laparoscopic (SIL splenectomy. Herein, we describe a patient undergoing SIL splenectomy for ITP without the use of a disposable port device. We report a 20-year-old female patient with steroid-refractory ITP having a platelet count of 14,000/cmm who underwent a SIL splenectomy. Dissection was facilitated by the use of a single articulating grasper and a gastric traction suture and splenic vessels were secured at the hilum with an endo-GIA stapler. She made an uneventful postoperative recovery and was discharged on the second postoperative day. She is doing well with no visible scar at 8-month follow-up.

  1. A new compound curved needle for intradermal suture closure.

    Science.gov (United States)

    Abidin, M R; Becker, D G; Paley, R D; Doctor, A; Westwater, J J; McGregor, W; Edlich, R F

    1989-01-01

    A new compound curved needle has been designed and developed for intradermal suture closure from a unique stainless steel alloy, American Society of Testing Materials (ASTM) 45500. This needle has a short, straight, sharpened point with a reverse cutting edge, followed by a curved distal section. Despite its geometry, it exhibited a similar resistance to bending and breakage as did a curved needle with a single radius of curvature manufactured from the same alloy. The design of this new needle enabled the physician to pass it through the dermis with a greater accuracy to a controlled depth and length of bite than curved cutting edge needle with a single radius of curvature. PMID:2691558

  2. Physical and Mechanical Properties of Natural Fibers Filled Polypropylene Composites and Its Recycle

    OpenAIRE

    Myrtha Karina; Holia Onggo; Anung Syampurwadi

    2007-01-01

    This study discusses the influence of natural fiber type on the performance of polypropylene and its recycle. Composites consisting of polypropylene (PP) and natural fiber from wood (Acacia mangium), water hyacinth (Eichornia crassipes), kenaf (Hibiscus cannabinus), banana (Musa paradisiaca) and empty fruit bunch of oil palm (Elaeis guineensis) were prepared by extrusion and compression process based on the ratio of 50:50% (w/w) with the addition of 2.5% polypropylene modified with maleic anh...

  3. Effect of volume fraction of Polypropylene Fiber on Mechanical Properties of Concrete

    OpenAIRE

    R. S. Rajguru,; Ghode, A. R.

    2014-01-01

    In this study, the result of polypropylene fiber on mechanical properties of concrete is studied. Polypropylene fibers of 12mm cut length and 6 denier were added at volume fraction of 0%, 0.25%, 0.50%, 0.75% & 1 %.The cube, cylinder and beams wear tested under two point loads on UTM. The results showed that the addition of polypropylene fiber significantly improved the compressive strength, split tensile strength, flexural strength, reserve strength and ductility of fiber rein...

  4. POLYPROPYLENE/STARCH BLENDS: STUDY OF THERMAL AND MORPHOLOGICAL PROPERTIES

    Scientific Electronic Library Online (English)

    MONICA A, PÉREZ R; BERNABÉ L, RIVAS Q; SADDYS, RODRÍGUEZ-LLAMAZARES.

    1643-16-01

    Full Text Available Polypropylene/starch blends were prepared using starch of different botanical source. The influence of starch type and starch content on thermal properties and morphology of polypropylene/starch blends was studied. Corn and potato starches were used as starch source. The starch content in the blends [...] was 7 and 15 wt-%. Characterization of PP and PP/starch blends by (DSC), (TGA), and (SEM) was carried out to obtain information on miscibility among PP and starch. The starch domains exhibited characteristic voids be due to thermal degradation. Two types of PP, PP1 poly(propylene-co-ethylene), random copolymer, and PP3 poly(propylene-co-ethylene), heterophasic copolymer were studied.

  5. Ziegler-Natta catalyst for polypropylene and polyethylene nanocomposites preparation

    International Nuclear Information System (INIS)

    Polypropylene and polyethylene nanocomposites are well known for their improved properties when compared with the neat polymers. In this work we report the preparation, characterization and the activity studies of a fourth generation Ziegler-Natta catalyst for the preparation of polyolefin/clay nanocomposites. The catalyst was prepared treating an organo-modified silicate with magnesium and titanium compounds. The content of titanium and that of the magnesium of the catalyst were determined by UV-vis spectroscopy and atomic absorption respectively. The first results show that the catalyst is active for propylene polymerization being suitable for polypropylene/clay nanocomposite preparation. The catalyst activity for ethylene polymerization was also investigated. The X-ray diffraction patterns of the polyethylene samples suggest the clay exfoliation occurs in the in situ polymerization, even with high clay loading (about 9 %) indicating that a nanocomposite was formed. (author)

  6. Determination of physicochemical changes in ion beam irradiated polypropylene

    International Nuclear Information System (INIS)

    Polypropylene was irradiated with 12C+ ions of 3.6 MeV energy. The spectral changes owing to ion bombardment were investigated followed by UV-VIS spectrophotometry. A gradual increase of absorbance in visible and near visible region with increase influence of ions was observed. The difference spectra shows formation of chromophoric groups with wavelength maximum near 400 nm at lower fluence, but at high fluence we observe a red shift in peak. The chromophoric groups are likely to be the extended conjugated polyene system and the red shift in peak position at high fluence may be attributed to a greater degree of conjugation. Gases (in the range of 2-80 amu) evolved due to interaction of polypropylene with 12C+ ions were measured with Residual Gas Analyzer. A large number of gaseous components were detected. This shows that polymer chain breaks into some smaller fragments which concomitantly lead to extended conjugation. (author)

  7. Rheological and Thermal Behavior of Polypropylene-Kaolin Composites

    International Nuclear Information System (INIS)

    Kaolins effect on rheological behaviour of polypropylene-kaolin composites was investigated. The research found that not only the kaolin content influence the rheological behaviour but also the compounding using internal mixer and twin screw extruder. In details, viscosity and shear stress increased with addition of kaolin content. These characteristics also exhibited higher in polypropylene-kaolin composite suspensions compounded using twin screw extruder than using internal mixer. Chain scission was assumed to occur and affect the melt properties. Further justification characterized by Differential Scanning Calorimeter (DSC) showed that the effect of kaolin and loading content were more evident on the onset melting temperature and crystallinity. Besides, due to the different cooling operation in both processes, the effect of compounding on melting characteristic was conspicuous. (author)

  8. Effects of environmental ageing on HMS-polypropylene/Cloisite nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Komatsu, L. G. H., E-mail: dfparra@ipen.br; Oliani, W. L., E-mail: dfparra@ipen.br; Ferreto, H. F. R., E-mail: dfparra@ipen.br; Lugao, A. B., E-mail: dfparra@ipen.br; Parra, D. F., E-mail: dfparra@ipen.br [Nuclear and Energy Research Institute, IPEN-CNEN/SP (Brazil)

    2014-05-15

    High melt strength polypropylene Nanocomposites (NC-HMSPP) were obtained with concentrations of 0.1 and 5 wt% of Cloisite 20A. The melt intercalation, using twin screw extruder was done to homogenize the nanocomposite in presence of polypropylene graft maleic anhydride (PP-g-MA) compatibilizer agent. In this work, the manufactured dumbbell samples were settled in device for natural ageing assay. The period of exposition was January to December of 2012. The effects of environmental ageing was determined by carbonyl index (FT-IR) and the results showed that nanocomposites were more stable than HMSPP. The mechanical properties (elongation and rupture strength) were evaluated and the thermal behavior was investigated by differential scanning calorimetry (DSC) and X ray diffraction (DRX). The morphology was observed by scanning electron microscopy (SEM) in which the nanocomposites showed intense cracks on the surface.

  9. Study of blends based on polypropylene and Epdm elastomer

    International Nuclear Information System (INIS)

    Polymer blends based on EPDM elastomer and isostatic polypropylene (P P) were prepared in a Bra bender plastograph, coupled with a Brabender mixer chamber, in different composition ranges and processing conditions. It was evaluated the mechanical and flow properties of EPDM/P P blends, and also the effect of the addition of controlled degraded polypropylene (P P-deg) on the properties of these mixtures. The characterization and the study of the compatibilization degree of EPDM/P P and EPDM/P P/P P-deg blends were analyzed by differential scanning calorimetry (DSC), thermal dynamic mechanical analysis (DTMA), thermal gravimetric analysis (TGA), 13 C-nuclear magnetic resonance (13C-NMR) and scanning electron microscopy (SEM). (author)

  10. Effects of environmental ageing on HMS-polypropylene/Cloisite nanocomposites

    International Nuclear Information System (INIS)

    High melt strength polypropylene Nanocomposites (NC-HMSPP) were obtained with concentrations of 0.1 and 5 wt% of Cloisite 20A. The melt intercalation, using twin screw extruder was done to homogenize the nanocomposite in presence of polypropylene graft maleic anhydride (PP-g-MA) compatibilizer agent. In this work, the manufactured dumbbell samples were settled in device for natural ageing assay. The period of exposition was January to December of 2012. The effects of environmental ageing was determined by carbonyl index (FT-IR) and the results showed that nanocomposites were more stable than HMSPP. The mechanical properties (elongation and rupture strength) were evaluated and the thermal behavior was investigated by differential scanning calorimetry (DSC) and X ray diffraction (DRX). The morphology was observed by scanning electron microscopy (SEM) in which the nanocomposites showed intense cracks on the surface

  11. Mechanical and morphological characterization of polypropylene toughened with olefinic elastomer

    Scientific Electronic Library Online (English)

    Cybele, Lotti; Carlos A., Correa; Sebastião V., Canevarolo.

    2000-04-01

    Full Text Available The effect of incorporating (C2-C8) ethylene-octene elastomer on the mechanical properties and morphology of polypropylene copolymers has been investigated employing two types of PP copolymer, with and without nucleating agent. The results were compared to the ones presented by a commercial PP heter [...] ophase (reactor impact modified PP/EPR). The addition of the elastomer increases the toughness of the blends but reduces their stiffness. PP blends in the low elastomer content region (

  12. Thermal simulation for geometric optimization of metallized polypropylene film capacitors

    OpenAIRE

    El-Husseini, M.; Venet, Pascal; Rojat, Gérard; Joubert, Charles

    2002-01-01

    In this paper, we use an analytic model to calculate the losses in the metallized polypropylene film capacitors. The model is validated experimentally for capacitors having the same capacitance but different geometry. For each group of capacitors a temperature distribution in the roll is assumed with the aim of optimizing its thermal performance. It appears that the heating of a long capacitor is higher than that of an equivalent flat capacitor subjected to the same electric stresses.

  13. Property Relationship in Organosilanes and Nanotubes Filled Polypropylene Hybrid Composites

    OpenAIRE

    Monsiva?is-barro?n, Alejandra J.; Jaime Bonilla-Rios; Antonio Sánchez-Fernández

    2014-01-01

    Polypropylene composites with different filler contents were prepared by creating a masterbatch containing 3 wt%. filler. A variety of silanol groups were used to synthetized three compounds in different media trough a sol-gel process with acetic acid, formic acid and ammonium hydroxide as catalysts. Besides, four different nanotubular fillers were also used to analyze their behavior and compare it with the effect caused by the silanol groups. These tubular structures comprise: unmodified hal...

  14. Bacterial Growth on Chitosan-Coated Polypropylene Textile

    OpenAIRE

    Erben, D.; Hola, V.; Jaros, J.; Rahel, J.

    2012-01-01

    Biofouling is a problem common in all systems where microorganisms and aqueous environment meet. Prevention of biofouling is therefore important in many industrial processes. The aim of this study was to develop a method to evaluate the ability of material coating to inhibit biofilm formation. Chitosan-coated polypropylene nonwoven textile was prepared using dielectric barrier discharge plasma activation. Resistance of the textile to biofouling was then tested. First, the textile was submerge...

  15. Detection of Cryptosporidium in water by using polypropylene cartridge filters.

    OpenAIRE

    Musial, C. E.; Arrowood, M. J.; Sterling, C. R.; Gerba, C. P.

    1987-01-01

    Members of the genus Cryptosporidium are protozoan parasites that cause gastroenteritis in humans and animals and appear to be spread largely by the fecal-oral route. A method was developed for the concentration and detection of Cryptosporidium oocysts in water to assess their occurrence in the environment and potential for waterborne disease transmission. This method was developed by using spun polypropylene cartridge filters. Optimal conditions for concentration, filter elution, filter poro...

  16. Properties of isotactic polypropylene irradiated in various atmospheres

    OpenAIRE

    Mili?evi? Dejan S.; Suljovruji? Edin H.

    2010-01-01

    In this paper, changes in structure and physical properties of stabilized isotactic polypropylene (iPP) were created by gamma irradiation, up to a dose of 700 kGy, in different media: air, deionized distilled (DD) water and acetylene. Two main effects occur when polyolefins, such as iPP, are subjected to ionizing radiation: crosslinking and scission of macromolecules. The domination of one or the other of these competitive processes is determined by both the structural peculiarities of the po...

  17. Study of the properties of polypropylene-PHB blends

    OpenAIRE

    Garci?a Quesada, Juan Carlos; Marcilla Gomis, Antonio; Barreiro Ortiz, Patricia; Gil Boj, Erika; Lo?pez Pastor, Miriam

    2007-01-01

    Polypropylene is ,with PVC and polyethylene, one of the most employed polymers for the production of daily life items. Although it is a thermoplastic polymer and nowadays the recycling conscience of the society is increasing, it is still found in urban wastes and therefore in landfills. Then, the main disadvantage is the permanence and the long life time of this type of plastics. The addition of biodegradable polymers has been claimed as a way to palliate this problem, since with degradation ...

  18. Nucleation of polypropylene with gold nanoparticles using sandwich method.

    Czech Academy of Sciences Publication Activity Database

    Pavlova, Ewa; Šlouf, Miroslav; Sikora, Antonín; J?za, Josef; Šandová, Hana; Baldrian, Josef; Piorkowska, E.

    Halle (Saale) : Martin Luther University Halle -Wittenberg, 2010 - (Radusch, H.; Fiedler, L.). s. 135 ISBN 978-3-86829-282-4. [International Scientific Conference on Polymeric Materials /14./. 15.09.2010-17.09.2010, Halle (Saale)] R&D Projects: GA ?R GAP205/10/0348 Institutional research plan: CEZ:AV0Z40500505 Keywords : nucleation * polypropylene * DSC Subject RIV: CF - Physical ; Theoretical Chemistry

  19. Die Rätsel der .beta.-Phase in isotaktischem Polypropylen.

    Czech Academy of Sciences Publication Activity Database

    Raab, Miroslav; Kotek, Ji?í; Grellmann, W.

    Halle Wittenberg : MartinLutherUniversität, 2003, s. -. [Tagung Deformation und Bruchverhalten von Kunststoffen /9./. Halle -Wittenberg (DE), 25.06.2003-27.06.2003] R&D Projects: GA ?R GA106/02/1249; GA ?R GP106/02/P027 Institutional research plan: CEZ:AV0Z4050913 Keywords : isotactic polypropylene * .beta. nucleation * hierarchical structure Subject RIV: CD - Macromolecular Chemistry

  20. Upgrading of recycled polypropylene by preparing flame retarded layered composite

    OpenAIRE

    Ronkay, F.; Gy. Marosi; Toldy, A.; Bodzay, B.; Fejos, M.; Bocz, K.

    2012-01-01

    Upgrading of polypropylene waste was performed by different composite technologies, in order to improve the flame retardancy combined with preserved or improved mechanical properties. The polymer waste of density below 900 kg/m3 is originated from end-of-life vehicles (ELV) after comminution, density separation and comprehensive analysis. Intumescent flame retardant system was used for reducing the flammability; while chopped glass fibre reinforcement was used to compensate the deterioration ...

  1. Mechanical properties of polypropylene/calcium carbonate nanocomposites

    OpenAIRE

    Daniel Eiras; Luiz Antonio Pessan

    2009-01-01

    The aim of this work was to study the influence of calcium carbonate nanoparticles in both tensile and impact mechanical properties of a polypropylene homopolymer. Four compositions of PP/CaCO3 nanocomposites were prepared in a co-rotational twin screw extruder machine with calcium carbonate content of 3, 5, 7 and 10 wt. (%) The tests included SEM analyzes together with EDS analyzer and FTIR spectroscopy for calcium carbonate, tensile and impact tests for PP and the nanocomposites. The result...

  2. Microstructure and mechanical properties of Polypropylene/Polycarbonate blends

    OpenAIRE

    J.C. Viana; Bilewicz, M; Król, M.; L.A. Dobrza?ski

    2008-01-01

    Purpose: Researches, which are presented in this paper, consider the effect of chosen different weight ratios polycarbonate blended in a polypropylene matrix (PP/PC) at variable injection moulding conditions and its effect on the microstructure, and also on fracture and flexural properties.Design/methodology/approach: Composites contain between 0 and 30 wt % of polycarbonate and changes at constant rate of 10wt%. Specimens were produced with advantage of melt manipulation technology, further ...

  3. Aqueous Processes for Dyeing Generic, Unmodified Polypropylene Fiber

    OpenAIRE

    Murari L. Gupta; Fred Cook

    2010-01-01

    Acid leuco vat dyeings of polypropylene (PP) fabrics in combinations of a trichromatic series of colorants (red, yellow and blue) plus an orange were performed in order to determine the compatibility of the component colorants in the developed single stage, batch exhaust dyeing process reported earlier. Cross-section micrographs of dyed fibers revealed the absence of "ring-dyeing". Tensile tests and X-ray crystallinity results confirmed that the developed dyeing process did not significantly...

  4. Fracture Toughness of Polypropylene-Based Particulate Composites

    OpenAIRE

    David Arencón; José Ignacio Velasco

    2009-01-01

    The fracture behaviour of polymers is strongly affected by the addition of rigid particles. Several features of the particles have a decisive influence on the values of the fracture toughness: shape and size, chemical nature, surface nature, concentration by volume, and orientation. Among those of thermoplastic matrix, polypropylene (PP) composites are the most industrially employed for many different application fields. Here, a review on the fracture behaviour of PP-based particulate composi...

  5. Effect of ?-irradiation on the structure, stability and transport properties of polypropylene membrane and Cyanex-301

    International Nuclear Information System (INIS)

    Polypropylene supported liquid membrane of Cyanex-301 was found to be promising for the separation of trivalent actinides and lanthanides. It is therefore important to study the effect of gamma radiation on the transport behaviour of polypropylene supported liquid membrane containing Cyanex-301 as carrier. In the present work polypropylene flatsheet and Cyanex-301 solution in dodecane were irradiated separately by gamma irradiation. The transport behavior of the SLM of the irradiated polypropylene flatsheets were correlated with its change in pore structure observed by scanning electron microscopy. (author)

  6. Study on the method of identification of irradiated polypropylene by ESR spectroscopy

    International Nuclear Information System (INIS)

    Electron spin resonance (ESR) signals were detected from irradiated polypropylene, which is widely used as packing material of food products. Optimum conditions were investigated for identifying irradiated food indirectly using ESR spectroscopy. From the ESR spectra, the g1, g2 and g3 factors for irradiated polypropylene were 2.0350±0.0002, 2.0089±0.0002 and 2.0052±0.0002, respectively. ESR intensity of irradiated polypropylene was positively correlated with microwave power, modulation amplitude and absorbed dose, and the detection limit was 0.5 kGy within 30 days post irradiation. The study provides a basis for identifying irradiated food products packed by polypropylene. (authors)

  7. Effectiveness of ultrasonographic evaluation of the cranial sutures in children with suspected craniosynostosis

    International Nuclear Information System (INIS)

    Computed tomography (CT) is the 'gold standard' for evaluation of the cranial sutures. While prenatal cranial suture evaluation with ultrasound (US) is common, US has not been established as a postnatal screening tool. We evaluated the effectiveness of US for diagnosis of craniosynostosis (CS). During 2006, 24 infants with questionable CS were assessed with US of the sagittal, metopic, and bilateral coronal and lambdoid sutures. US findings and clinical records were reviewed retrospectively. Sixteen boys and eight girls (ages 1-11 months, mean 4.3) underwent US. The correct diagnosis was provided in 23 (95%), with equivocal findings in one patient. Cranial sutures appeared normal in 15 infants, who had normal clinical presentation at mean 5.8 months follow-up; CT confirmation was obtained in two. In eight children, US identified premature closure of one or more cranial sutures. Three-dimensional CT was performed as a preparation for surgery in four, with classical CS findings. In one case with inconclusive US findings, CT showed narrow but open sutures. Sonographic examination of cranial sutures may serve as a first imaging tool for evaluation of craniosynostosis. CT may be reserved for children with abnormal or equivocal ultrasound and for preoperative planning. (orig.)

  8. Effectiveness of ultrasonographic evaluation of the cranial sutures in children with suspected craniosynostosis

    Energy Technology Data Exchange (ETDEWEB)

    Simanovsky, Natalia; Hiller, Nurith; Koplewitz, Benjamin; Rozovsky, Katya [Hadassah Hebrew University Medical Center, Department of Medical Imaging, Mount, Scopus, P.O. Box 24035, Jerusalem (Israel)

    2009-03-15

    Computed tomography (CT) is the 'gold standard' for evaluation of the cranial sutures. While prenatal cranial suture evaluation with ultrasound (US) is common, US has not been established as a postnatal screening tool. We evaluated the effectiveness of US for diagnosis of craniosynostosis (CS). During 2006, 24 infants with questionable CS were assessed with US of the sagittal, metopic, and bilateral coronal and lambdoid sutures. US findings and clinical records were reviewed retrospectively. Sixteen boys and eight girls (ages 1-11 months, mean 4.3) underwent US. The correct diagnosis was provided in 23 (95%), with equivocal findings in one patient. Cranial sutures appeared normal in 15 infants, who had normal clinical presentation at mean 5.8 months follow-up; CT confirmation was obtained in two. In eight children, US identified premature closure of one or more cranial sutures. Three-dimensional CT was performed as a preparation for surgery in four, with classical CS findings. In one case with inconclusive US findings, CT showed narrow but open sutures. Sonographic examination of cranial sutures may serve as a first imaging tool for evaluation of craniosynostosis. CT may be reserved for children with abnormal or equivocal ultrasound and for preoperative planning. (orig.)

  9. Radiological assessment of skull base changes in children with syndromic craniosynostosis: role of ''minor'' sutures

    International Nuclear Information System (INIS)

    This study aims to identify the premature synostosis of ''major'' and ''minor'' sutures of the four ''sutural arches'' of the skull and to perform a morphometric analysis in children with syndromic craniosynostosis in order to evaluate changes in the skull base linked with premature suture synostosis. We reviewed multiplanar high-resolution CT images, implemented with 3D reconstructions, from 18 patients with complex syndromic craniosynostosis and compared them with 18 age-matched healthy subjects. We assessed the calvarial sutures and their extension to the skull base, and then we correlated specific types of synostosis with the size, shape and symmetry of the cranial fossae. We found a marked asymmetry of the skull base growth in all patients. The synostotic involvement around the coronal ring caused a reduction in the growth of the anterior and middle fossae. The size of the posterior cranial fossa was related not only to ''major'' but also to ''minor'' suture synostosis of the lambdoid and parieto-squamosal arches. Changes in the skull base and craniofacial axis symmetry are due to structural and functional relationships between ''major'' and ''minor'' skull sutures, suggesting a structural and functional relationship between the neurocranium and basicranium. The early recognition of prematurely closed skull base sutures may help clinicians and neurosurgeons to establish correct therapeutic approaches. (orig.)

  10. Immunostimulatory sutures that treat local disease recurrence following primary tumor resection

    International Nuclear Information System (INIS)

    Neuroblastoma is a common childhood cancer that often results in progressive minimal residual disease after primary tumor resection. Cytosine-phosphorothioate-guanine oligonucleotides (CpG ODN) have been reported to induce potent anti-tumor immune responses. In this communication, we report on the development of a CpG ODN-loaded suture that can close up the wound following tumor excision and provide sustained localized delivery of CpG ODN to treat local disease recurrence. The suture was prepared by melt extruding a mixture of polylactic acid-co-glycolic acid (PLGA 75:25 0.47 dL g-1) pellets and CpG ODN 1826. Scanning electron microscopy images showed that the sutures were free of defects and cracks. UV spectrophotometry measurements at 260 nm showed that sutures provide sustained release of CpG ODN over 35 days. Syngeneic female A/J mice were inoculated subcutaneously with 1 x 106 Neuro-2a murine neuroblastoma wild-type cells and tumors were grown between 5 to 10 mm before the tumors were excised. Wounds from the tumor resection were closed using CpG ODN-loaded sutures and/or polyglycolic acid Vicryl suture. Suppression of neuroblastoma recurrence and mouse survival were significantly higher in mice where wounds were closed using the CpG ODN-loaded sutures relative to all other groups. (communication)

  11. Immunostimulatory sutures that treat local disease recurrence following primary tumor resection

    Energy Technology Data Exchange (ETDEWEB)

    Intra, Janjira; Zhang Xueqing; Salem, Aliasger K [Division of Pharmaceutics, College of Pharmacy, University of Iowa, Iowa City, IA 52242 (United States); Williams, Robin L; Zhu Xiaoyan [Department of Surgery, Roy J and Lucille Carver College of Medicine, University of Iowa, Iowa City, IA 52242 (United States); Sandler, Anthony D, E-mail: aliasger-salem@uiowa.edu [Department of Surgery and Center for Cancer and Immunology Research, Children' s National Medical Center, Washington DC 20010 (United States)

    2011-02-15

    Neuroblastoma is a common childhood cancer that often results in progressive minimal residual disease after primary tumor resection. Cytosine-phosphorothioate-guanine oligonucleotides (CpG ODN) have been reported to induce potent anti-tumor immune responses. In this communication, we report on the development of a CpG ODN-loaded suture that can close up the wound following tumor excision and provide sustained localized delivery of CpG ODN to treat local disease recurrence. The suture was prepared by melt extruding a mixture of polylactic acid-co-glycolic acid (PLGA 75:25 0.47 dL g{sup -1}) pellets and CpG ODN 1826. Scanning electron microscopy images showed that the sutures were free of defects and cracks. UV spectrophotometry measurements at 260 nm showed that sutures provide sustained release of CpG ODN over 35 days. Syngeneic female A/J mice were inoculated subcutaneously with 1 x 10{sup 6} Neuro-2a murine neuroblastoma wild-type cells and tumors were grown between 5 to 10 mm before the tumors were excised. Wounds from the tumor resection were closed using CpG ODN-loaded sutures and/or polyglycolic acid Vicryl suture. Suppression of neuroblastoma recurrence and mouse survival were significantly higher in mice where wounds were closed using the CpG ODN-loaded sutures relative to all other groups. (communication)

  12. Development of silver nano-coatings on silk sutures as a novel approach against surgical infections.

    Science.gov (United States)

    De Simone, S; Gallo, A L; Paladini, F; Sannino, A; Pollini, M

    2014-09-01

    The infections give rise to a range of clinical problems and prolong hospitalization with increased healthcare costs. Moreover, persistent infections exasperate the problem of antibiotic resistance. The aim of this study was the development of effective and low-cost antibacterial silver coatings on surgical sutures by adopting an innovative photochemical deposition process to prevent early contamination of surgical wounds. The silver deposition technology adopted in this work is an innovative process based on the in situ photoreduction of a silver solution. The samples were dipped in the silver solution and then exposed to UV radiation in order to induce the synthesis of silver clusters on the surface of the suture. The homogeneous distribution of silver particles on the surface and on the cross-section of the treated sutures was demonstrated. All the antibacterial studies clearly demonstrated that the use of novel silver treated sutures could represent clinical advantages in terms of the prevention of surgical infections against bacterial colonization. The silver coating deposited on the sutures demonstrated no cytotoxic effect on a selected cell population. The results obtained suggested that the antibacterial silver-coated sutures developed in this work could represent an interesting alternative to conventional sutures, with evident advantages in terms of prevention of the surgical infections and on the health costs. In addiction, very low concentrations of silver significantly inhibited the microbial load, without affecting the cell viability. PMID:24997984

  13. Study of gel formation in polypropylene modified by gamma irradiation

    International Nuclear Information System (INIS)

    The linearity of the chains of iPP (isotactic polypropylene) confers to this, low melt strength. This fact limits the use of iPP in processes that demand high stretching. The graft of branches confers improvements in its extensional viscosity, resulting in Polypropylene with High Melt Strength (HMS-PP). Preparation process of the HMS-PP, included iPP in pellets, conditioned in plastic container containing acetylene under pressure of 110 kPa and radiation with ? source of 60Co in the doses of 5, 12.5 and 20 kGy. The gel fraction of the samples was determined by the extraction of soluble components in xylene under boiling for 12 hours at 138 deg C. The soluble part of the samples was decanted with the total volatilization of the xylene to the room temperature (25 deg C) and deposition in glass blades. These samples had been characterized by Optic Microscopy, Scanning Electron Microscopy and Infrared Spectroscopy. In this study of the morphology, we obtained the formation of gel and microgel of polypropylene with higher incidence in HMS-PP 20 kGy. (author)

  14. Pubovaginal sling with a low-cost polypropylene mesh

    Scientific Electronic Library Online (English)

    Fransber R., Rodrigues; Romulo, Maroccolo Filho; Roberto R., Maroccolo; Lucio C., Paiva; Fernando A., Diaz; Eduardo C., Ribeiro.

    2007-10-01

    Full Text Available OBJECTIVE: The aim of this study was to present the results of pubovaginal sling with a low-cost polypropylene mesh in the treatment of stress urinary incontinence MATERIALS AND METHODS: 118 women diagnosed with stress urinary incontinence (SUI) due to urethral hypermobility or intrinsic sphincteric [...] deficiency, treated with pubovaginal sling (PVS) with a low-cost polypropylene mesh confectioned by the surgeon, were analyzed. All patients had a basic evaluation that included a medical history, physical examination, stress tests and urodynamic investigation RESULTS: The average follow up was of 42 months. Urethral hypermobility was observed in 67% of the cases. The process was carried out on an outpatient basis on 67 patients. Intra-operative complications included 4 vesical injuries, treated with catheterization for 3 days. There were 13 early complications, of which 8 were urinary retentions treated with vesical drainage for 1 to 3 weeks and 3 vaginal extrusions of the mesh treated with covering of the sections with mucous membrane. There was a need for 6 urethrolysis in patients who presented irritative and postoperative obstructive symptoms; 81.3% of the patients were considered cured, while 9.3% had significant improvement. Three initially unsuccessful cases required sling reconfiguration. All cases were eventually cured CONCLUSION: The construction of a pubovaginal sling using a low-cost polypropylene mesh is a safe and effective technique for the relief of SUI. It should be considered an alternative, especially for patients in public health systems with low financial resources.

  15. Pubovaginal sling with a low-cost polypropylene mesh

    Directory of Open Access Journals (Sweden)

    Fransber R. Rodrigues

    2007-10-01

    Full Text Available OBJECTIVE: The aim of this study was to present the results of pubovaginal sling with a low-cost polypropylene mesh in the treatment of stress urinary incontinence MATERIALS AND METHODS: 118 women diagnosed with stress urinary incontinence (SUI due to urethral hypermobility or intrinsic sphincteric deficiency, treated with pubovaginal sling (PVS with a low-cost polypropylene mesh confectioned by the surgeon, were analyzed. All patients had a basic evaluation that included a medical history, physical examination, stress tests and urodynamic investigation RESULTS: The average follow up was of 42 months. Urethral hypermobility was observed in 67% of the cases. The process was carried out on an outpatient basis on 67 patients. Intra-operative complications included 4 vesical injuries, treated with catheterization for 3 days. There were 13 early complications, of which 8 were urinary retentions treated with vesical drainage for 1 to 3 weeks and 3 vaginal extrusions of the mesh treated with covering of the sections with mucous membrane. There was a need for 6 urethrolysis in patients who presented irritative and postoperative obstructive symptoms; 81.3% of the patients were considered cured, while 9.3% had significant improvement. Three initially unsuccessful cases required sling reconfiguration. All cases were eventually cured CONCLUSION: The construction of a pubovaginal sling using a low-cost polypropylene mesh is a safe and effective technique for the relief of SUI. It should be considered an alternative, especially for patients in public health systems with low financial resources.

  16. Rheological study of polypropylene irradiated with polyfunctional monomers

    International Nuclear Information System (INIS)

    The aim of this paper is to investigate the rheological properties of polypropylene (PP) modified by ionization radiation (gamma rays) in the presence of two different monomers. The samples were mixed in a twin-screw extruder with ethylene glycol dimethacrylate (EGDMA) or trimethylolpropane trimethacrylate (TMPTMA) with concentration in the range of 0.5-5.0 mmol. After that, they were irradiated with 20 kGy dose of gamma radiation. The structural modification of polypropylene was analyzed in the melt state by measuring melt flow rate (MFR), ?* (complex viscosity) and G' (storage modulus) in the angular frequency range of 10-1 to 3 x 102 rad s-1. From the oscillatory rheology data, one could obtain the values of ?0 (zero shear viscosity) that would be related to the molar mass. All results were discussed with respect to the crosslinking and degradation process that occur in the post-reactor treatment to produce controlled rheology polypropylene. The resulting polymeric materials were submitted the cytotoxicity in vitro test by neutral red uptake methodology with NCTC L 929 cell line from American Type Culture Collection bank. All modified PP samples presented no cytotoxicity

  17. Development and characterisation of injection moulded, all-polypropylene composites

    Directory of Open Access Journals (Sweden)

    A. Kmetty

    2013-02-01

    Full Text Available In this work, all-polypropylene composites (all-PP composites were manufactured by injection moulding. Prior to injection moulding, pre-impregnated pellets were prepared by a three-step process (filament winding, compression moulding and pelletizing. A highly oriented polypropylene multifilament was used as the reinforcement material, and a random polypropylene copolymer (with ethylene was used as the matrix material. Plaque specimens were injection moulded from the pellets with either a film gate or a fan gate. The compression moulded sheets and injection moulding plaques were characterised by shrinkage tests, static tensile tests, dynamic mechanical analysis and falling weight impact tests; the fibre distribution and fibre/matrix adhesion were analysed with light microscopy and scanning electron microscopy. The results showed that with increasing fibre content, both the yield stress and the perforation energy significantly increased. Of the two types of gates used, the fan gate caused the mechanical properties of the plaque specimens to become more homogeneous (i.e., the differences in behaviour parallel and perpendicular to the flow direction became negligible.

  18. Fatigue mechanisms in unidirectional glass-fibre-reinforced polypropylene

    DEFF Research Database (Denmark)

    Gamstedt, E.K.; Berglund, L.A.

    1999-01-01

    Polypropylene (PP) and polypropylene modified with maleic anhydride (MA-PP) reinforced by continuous longitudinal glass fibres have been investigated. The most prominent effect of the modification with maleic anhydride in the composite is a stronger fibre/matrix interface. The effects of interfacial strength on fatigue performance and on the underlying micromechanisms have been studied for these composite systems. Tension-tension fatigue tests (R = 0.1) were carried out on 0 degrees glass-fibre/PP and glass-fibre/ MA-PP coupons. The macroscopic fatigue behaviour was characterized in terms of stiffness reduction and fatigue-life curves. The results showed that the longitudinal Young's modulus degraded more rapidly for glass-fibre/PP, which was caused by a higher degree of damage growth and accumulation. The improvement in monotonic strength was negligible, but the fatigue life was prolonged by about one decade for the composite with the stronger interface by use of the maleic-anhydride grafted polypropylene matrix. During the fatigue testing, the microscopic mechanisms were monitored intermittently by a surface replication technique. From microscopic observations, it could be concluded that the better fatigue resistance of glass-fibre/MA-PP can be attributed to the greater interfacial strength and the resistance to debond propagation. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.

  19. Flame retardant polypropylene nanocomposites reinforced with surface treated carbon nanotubes

    Science.gov (United States)

    Guleria, Abhishant

    Polypropylene nanocomposites are prepared by reinforcing carbon nanotubes by ex-situ solution mixing method. Interfacial dispersion of carbon nanotubes in polypropylene have been improved by surface modification of CNTs and adding surfactants. Polypropylene nanocomposites fabrication was done after treating CNTs. Firstly, oxidation of CNTs followed by silanization for addition of functionalized groups on the surface of CNTs. Maleic anhydride grafted PPs were used as surfactants. Maleic anhydrides with two different molecular weights were LAMPP and HMAPP. Successful oxidation of CNTs by nitric acid and functionalized CNTs by 3-Aminopropyltriethoxysilane was confirmed by attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) with evidence of absorption peak at 1700 and 1100-1000 cm-1. Scanning electron microscopy (SEM) micrographs revealed that the CNTs dispersion quality was improved by directly adding LMAPP/HMAPP into PP/CNTs system and the PP-CNTs adhesion was enhanced through both the CNTs surface treatment and the addition of surfactant. Thermal gravimetric analysis (TGA) revealed an enhanced thermal stability in the PP/CNTs and PP/CNTs/MAPP. Differential scanning calorimetry (DSC) characterization demonstrated that the crystalline temperature, fusion heat and crystalline fraction of hosting PP were decreased with the introduction of CNTs and surface treated CNTs; however, melting temperature was only slightly changed. Melting rheological behaviors including complex viscosity, storage modulus, and loss modulus indicated significant changes in the PP/MAPP/CNTs system before and after functionalization of CNTs, and the mechanism were also discussed in details.

  20. Property Relationship in Organosilanes and Nanotubes Filled Polypropylene Hybrid Composites

    Directory of Open Access Journals (Sweden)

    Alejandra J. Monsiváis-Barrón

    2014-10-01

    Full Text Available Polypropylene composites with different filler contents were prepared by creating a masterbatch containing 3 wt%. filler. A variety of silanol groups were used to synthetized three compounds in different media trough a sol-gel process with acetic acid, formic acid and ammonium hydroxide as catalysts. Besides, four different nanotubular fillers were also used to analyze their behavior and compare it with the effect caused by the silanol groups. These tubular structures comprise: unmodified halloysite, carbon nanotubes and functionalized halloysite and carbon nanotubes. Morphological characterization in SEM and STEM/TEM showed dispersion in the polypropylene matrix. According to TGA and DSC measurements thermal behavior remain similar for all the composites. Mechanical test in tension demonstrate that modulus of the composites increases for all samples with a major impact for materials containing silanol groups synthetized in formic acid. Rheological measurements show a significantly increment in viscosity for samples containing unmodified and modified carbon nanotubes. No difference was found for samples containing silanol groups and halloysite when compared to neat polypropylene. Finally, the oxygen transmission rate increased for all samples showing high barrier properties only for samples containing natural and functionalized halloysite nanotubes.

  1. Contact angle analysis of corona treated polypropylene films

    International Nuclear Information System (INIS)

    In this work, the effect of the surface modification of polypropylene films via corona treatment was investigated. Polypropylene films were treated with negative and positive corona discharge, at atmospheric pressure, for 5 minutes, at two different temperatures – 25 °C and 90 °C. The changes in the surface free energy were investigated by means of contact angle measurements. The Bickerman's method was applied to determine the polar and dispersion components of the polymer surface free energy, on the basis of the theory of Owens, Wendt, Kaelble and Uy. Atomic force microscopy was used to analyze the polymer surface morphology changes of the films with temperature. According to the findings, in all cases the corona treatment increases the surface free energy of polypropylene films and its polar part, in comparison with the untreated samples. The effects of negative and positive corona polarities display some specific features which could be associated with different charged group introduced onto the film surface during the corona treatment. The total final effect depends on the simultaneous action of the two competing factors – temperature and corona polarity. The most pronounced effect was observed for high temperature negative corona treatment.

  2. Effects of radiation on the structure of polypropylene

    International Nuclear Information System (INIS)

    The effects of high-energy radiation on the physical arrangement of macromolecules in atactic polypropylene (aPP) and radiation-amorphized isotactic polypropylene (iPP) were examined using the differential radial distribution function (DRDF) technique. The resultant DRDF curve for 0 Mrad aPP showed three intermolecular peaks at 6.6, 13.0, and 17.7 A and two intramolecular peaks at 1.5 and 2.5 A. The appearance of the periodic intermolecular DRDF peaks suggested the packing of parallel chains of --18 A in the polymer. The 17.7 A peak disappeared when the aPP sample was irradiated to 115 Mrad, indicating the occurrence of structure deterioration from 18 A to 13 A. As a result of severe deterioration of the intermolecular organization, DRDF curves for 400 and 1300 Mrad iPP samples each showed only one intermolecular peak at --7 A. This deterioration was attributed to the crosslinking-induced increase in lattice distortions. The results were compared with previous studies on irradiation of natural rubber (NR) and polyethylene (PE). It appears that radiation was more effective in causing deterioration of the intermolecular organization in polypropylene than in NR and PE. This was explained by the different radiation chemistry of the polymers. (author)

  3. Knot security, loop security, and elongation of braided polyblend sutures used for arthroscopic knots.

    Science.gov (United States)

    Livermore, Ryan W; Chong, Alexander C M; Prohaska, Daniel J; Cooke, Francis W; Jones, Teresa L

    2010-12-01

    In the study described here, we evaluated load to failure and cyclic loading elongation of different braided polyblend sutures under different sliding knot configurations. Four braided polyblend sutures (FiberWire, Herculine, Orthocord, Ultrabraid) were tied with 5 sliding arthroscopic knots (Static surgeon, Weston, Roeder, Nicky, Tennessee slider) with a series of 3 reversing half-hitches on alternating posts (RHAPs). Each knot was tied around a 30-mm circumference post to ensure a consistent loop circumference. Loop security was measured as load to failure (load at 3-mm cross-head displacement or suture breakage) and loop elongation at a frequency of 1 Hz from 6 N to 30 N for 1000 cycles. Twenty knots were tied for each possible combination of knots and sutures, 10 for load to failure and 10 for cyclic loading test. For any given knot type, tying with Ultrabraid suture material resulted in maximum performance in the maximum load-to-failure test. Conversely, tying with Orthocord resulted in a significantly lower maximum load to failure, with the exception of the Surgeon knot. The Weston knot with 3 RHAPs using Ultrabraid provided the highest load to failure(mean, 346 N; SD, 24 N). All knots elongated less than 0.45 mm at the 1000th cycle and experienced higher suture slippage at initial cyclic loading (50th cycles). At higher cycles, FiberWire and Orthocord demonstrated less than half of the suture slippage of Herculine and Ultrabraid (5x10(-5) vs 11x10(-5) mm/cycle). Different braided polyblend sutures provide different knot and loop security for a given type of sliding knot. All knots in this study appear to be durable with respect to resistance to loosening under cyclic loading conditions. The Weston knot with 3 RHAPs using Ultrabraid provided the best loop and knot security. Our study results help further our understanding of the biomechanics of knot and loop security differences for different braided polyblend sutures. PMID:21720573

  4. Experimental studies on the influence of irradiation (60Co) on wound healing of colonic suture

    International Nuclear Information System (INIS)

    Effects of preoperative 60Co irradiation on wound healing of colonic suture in adult dogs of mixed breed were discussed. Wound healing 7 days after colonic suture was compared among dogs which received colonic suture immediately, or 3 days, or 7 days after the 60Co irradiation. As a result, there was not a big difference in their wound healing among these dogs, and disorders of wound healing were not found. Bursting pressure at sutured sites was always lower in irradiated dogs than controls. Recovery of the bursting pressure was 2 days slower in irradiated dogs than non-irradiated dogs for 7 days after the suture. Bursting pressure was the lowest on the 3rd day after the suture in both groups. As to fine changes in irradiated dogs, appearance of recommunicating phenomena in blood vessels, delay of a decrease in avascular regions, delay of granulation, and hypertrophy of vascular walls seemed to be influenced by 60Co irradiation, but there was not a big difference in these results between irradiated and non-irradiated dogs. An increase in postoperative concentration of hydroproline tended to be little lower in irradiated dogs than controls, which seemed to be influenced by the 60Co irradiation. This result was also suggested from delay of granulation and remaining inflammations. Effects of 60Co irradiation on wound healing of colonic suture seemed to be slight generally, because ruptured suture scarecely occurred icause ruptured suture scarecely occurred in the irradiated dogs. When doses used in this experiment were calculated roughly by Ellis's method, irradiation of 60Co seemed not to influence seriously wound healing if the total of 2,000 to 2,500 rad was irradiated in 8 to 10 doses to human colon. (Tsunoda, M.)

  5. Stabilization of polypropylene, polypropylene blends with poly (styrene-b-(ethylene-co-butylene)-b-styrene) under irradiation: A comparative investigation

    International Nuclear Information System (INIS)

    The aim of this paper is to investigate the stabilization of polypropylene in the poly (styrene-b-(ethylene-co-butylene)-b-styrene) (SEBS)/polypropylene (PP) blends under irradiation with respect to PP. The PP films, SEBS/PP films were subjected to electron beam irradiation and characterized by wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), gel permeation chromatography (GPC), and dynamic mechanical thermal analysis (DMTA). It demonstrated that upon irradiation, the molecular weight of PP had a pronounced decrease due to the major chain scission, and the minor chain cross-linking or chain branching occurred at the higher irradiation dose. Stabilization of PP was improved in the presence of SEBS, exhibiting an enhanced irradiation resistance.

  6. Sutura intestinal monoplano extramucosa en dos hemisurget en pacientes con operaciones abdominales / Single layer intestinal extramucosal suturing using two semi-continuous sutures in patients with abdominal surgery

    Scientific Electronic Library Online (English)

    Yury, Valle Lara; Vivian, Rodríguez Tápanes.

    2012-06-01

    Full Text Available Objetivo: comparar el empleo de la sutura intestinal monoplano extramucosa en dos hemisurget con la sutura en dos planos, en pacientes con operaciones abdominales. Métodos: se realizó un estudio observacional-analítico de tipo prospectivo, de evaluación de tecnología quirúrgica, controlado, aleatori [...] zado y a simple ciegas, en 126 pacientes mayores de 15 años de edad, de ambos sexos. En 76 se empleó el método monoplano extramucosa en dos hemisurget y en 50 pacientes se utilizó el método de sutura intestinal en dos planos. Se tuvo en cuenta la frecuencia y el tipo de las complicaciones y su relación con el método de sutura empleado, así como la influencia en el tiempo quirúrgico y el tiempo de estadía hospitalaria. Resultados: con el método monoplano extramucosa en dos hemisurget, solo 13 pacientes sufrieron algún tipo de complicación; 64 pacientes (84,2 %) fueron intervenidos en un tiempo menor a las 2 h y el 80,3 % tuvo una estadía hospitalaria menor de 7 días. Las complicaciones más frecuentes en ambos grupos fueron la infección del sitito operatorio, las fístulas estercoráceas y la dehiscencia parcial de la sutura. La sutura intestinal monoplano extramucosa en dos hemisurget presentó menor frecuencia de complicaciones y una disminución considerable en el tiempo quirúrgico y la estadía hospitalaria. Conclusiones: la sutura intestinal monoplano en dos hemisurget resulta el método de elección para la sutura intestinal. Abstract in english Objective: compare the use of single layer intestinal extramucosal suturing using two semi-continuous sutures versus two-layer suturing in patients with abdominal surgery. Methods: a controlled randomized single-blind observational-analytical prospective surgical technique evaluation study was condu [...] cted with 126 patients of both sexes aged over 15. The single-layer extramucosal method using two semi-continuous sutures was used in 76 patients, and the two-layer intestinal suturing method in 50. Account was taken of the frequency and type of complications, and their relation to the suturing method used, as well as the influence upon surgical time and the length of hospital stay. Results: with the single layer extramucosal method using two semi-continuous sutures only 13 patients had complications of any sort; surgical time was under 2 h in 64 patients (84.2 %), and the length of hospital stay was under 7 days in 80.3 %. The most common complications in both groups were surgical site infection, stercoraceous fistulas and partial suture dehiscence. Single layer intestinal extramucosal suturing using two semi-continuous sutures showed a lower rate of complications and a considerable decrease in surgical time and length of hospital stay. Conclusions: single layer intestinal suturing using two semi-continuous sutures is the method of choice for intestinal suturing.

  7. Microsurgical reparation of facial nerve of Wistar rat with suture – Part 1

    Directory of Open Access Journals (Sweden)

    João Armando BRANCHER

    2005-05-01

    Full Text Available The right-side facial nerve of 20 Wistar rats was trans-sectioned and,immediately treated with three plain epineural suture stitches. Analysisof the results was based on histopathological aspects of the anastomoticarea. It was noticed that the presence of the suture material was responsible for the poor directioning of the nerve fibers and the neuroma formation in the anastomosis area, due to the collision of the regenerating nerve fibers with the granulomatous reaction to the suture string. Wallerian degeneration and proliferation of fibrous tissue were noticed.

  8. Cork extractives exhibit thermo-oxidative protection properties in polypropylene-cork composites and as direct additives for polypropylene

    OpenAIRE

    Aroso, Ivo; Fernandes, E. M.; Pires, R. A.; Mano, J. F.; Reis, R. L.

    2015-01-01

    The thermo-oxidative stability of polypropylene (PP) in composites containing 15??wt.% of cork and the performance of selected cork extracts as stabilizing additives for PP was evaluated by Oxidation Induction Time (OIT) and by Oxidation Onset Temperature (OOT). The results showed that cork increases the OIT of PP in the composite and it was identified that the cork extractives fraction is responsible for such behavior. Selected cork extracts with high antioxidant capacity (determined by dpph...

  9. Polypropylene and polypropylene/polyglecaprone (Ultrapro(r)) meshes in the repair of incisional hernia in rats

    Scientific Electronic Library Online (English)

    Edivaldo Massazo, Utiyama; Maria Beatriz Sartor de Faria, Rosa; Marina de Paula, Andres; Jocielle Santos de, Miranda; Sérgio Henrique Bastos, Damous; Cláudio Augusto Vianna, Birolini; Luciana Lamarão, Damous; Edna Frasson de Souza, Montero.

    2015-06-01

    Full Text Available PURPOSE: To compare the inflammatory response of three different meshes on abdominal hernia repair in an experimental model of incisional hernia. METHODS: Median fascial incision and skin synthesis was performed on 30 Wistar rats. After 21 days, abdominal hernia developed was corrected as follows: [...] 1) No mesh; 2) Polypropylene mesh; and, 3) Ultrapro(r) mesh. After 21 days, the mesh and surrounding tissue were submitted to macroscopic (presence of adhesions, mesh retraction), microscopic analysis to identify and quantify the inflammatory and fibrotic response using a score based on a predefined scale of 0-3 degrees, evaluating infiltration of macrophages, giant cells, neutrophils and lymphocytes. RESULTS: No significant difference was seen among groups in adherences, fibrosis, giant cells, macrophages, neutrophils or lymphocytes (p>0.05). Mesh shrinkage was observed in all groups, but also no difference was observed between polypropylene and Ultrapro mesh (7.0±9.9 vs. 7.4±10.1, respectively, p=0.967). Post-operatory complications included fistula, abscess, dehiscence, serohematic collection and reherniation, but with no difference among groups (p=0.363). CONCLUSION: There is no difference between polypropylene (high-density) and Ultrapro(r) (low-density) meshes at 21 days after surgery in extraperitoneal use in rats, comparing inflammatory response, mesh shortening, adhesions or complications.

  10. Development of novel melt-compounded starch-grafted polypropylene/polypropylene-grafted maleic anhydride/organoclay ternary hybrids

    Directory of Open Access Journals (Sweden)

    E. Lafranche

    2012-11-01

    Full Text Available Starch-grafted polypropylene (PP-g-starch/organoclay nanocomposites were melt-compounded using a corotating twin-screw extruder. Homopolymer or copolymer-based polypropylene-grafted maleic anhydrides (PP-g-MA with different molecular weights and different maleic anhydride (MA grafting levels were added at different weight contents as compatibilizer. Two organo-modified montmorillonites were used, the first one containing polar functional groups (Cloisite®30B having affinity to the starch phase, and the other one containing non polar-groups (Cloisite®20A having affinity to the polypropylene phase of the polymer matrix. Whatever the MA grafting level and the molecular weight and content of PP-g-MA, no significant immiscibility of PP-g-starch/PP-g-MA blends is evidenced. Regarding clay dispersion, adding a low content of ethylene-propylene copolymer-based PP-g-MA compatibilizer having a high MA-grafting level, and a polar organoclay (Cloisite®30B is the most desirable formulation to optimize clay intercalation and exfoliation in PP-g-starch. Nevertheless, regarding the reinforcement effect, whatever the PP-g-MA compatibilizer, the addition of non polar organoclay (Cloisite®20A is preferably recommended to reach higher tensile properties (modulus, yield stress, strength without significant loss of ductility.

  11. Effects of maleated polypropylene on the morphology, thermal and mechanical properties of short carbon fiber reinforced polypropylene composites

    International Nuclear Information System (INIS)

    Highlights: ? Carbon fibers (CFs) are the most widely used advanced reinforcing fiber materials. ? Improvement of adhesion between polypropylene (PP) matrix and CF were aimed. ? PP matrix was modified by addition of maleic anhydride grafted PP (PP-g-MAH). ? Mechanical properties of the composites were improved by PP-g-MAH compatibilizer. ? Modification of matrix with PP-g-MAH was improved the interfacial adhesion. -- Abstract: The aim of this study was to determine the effect of the maleic anhydride grafted polypropylene (PP-g-MAH) on the properties of short carbon fiber (CF) reinforced polypropylene (PP) composites. The composites were prepared by melt blending and injection molding techniques at different percentages of CF. Tensile tests, hardness, differential scanning calorimeter (DSC) and scanning electron microscopy (SEM) were performed to characterize the physical and morphological properties of the prepared composites. It was observed from SEM photographs that modification with PP-g-MAH improved the interfacial adhesion between the carbon fibers and PP matrix. The ultimate tensile strength, hardness and modulus values of modified PP composites were higher compared to the values of CF reinforced PP composites. Melting temperature of all composites was not changed significantly with increasing CF content; however degree of crystallinity values were decreased with the increasing CF content level.

  12. Suture-related keratitis following cataract surgery caused by methicillin-resistant Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Ahmad B Tarabishy

    2010-03-01

    Full Text Available Ahmad B Tarabishy1, Thomas L Steinemann21Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA; 2Cornea and External Eye Disease, MetroHealth Medical Center, Case Western Reserve University, Cleveland, OH, USAAbstract: A 54-year old-man presented with a two-day history of severe pain and decreased vision. Examination revealed a corneal ulcer associated with a loose suture from cataract surgery done approximately two years ago. The suture was removed and the patient was started on topic antibiotic treatment with cefazolin and gentamycin. Cultures revealed methicillin-resistant Staphylococcus aureus (MRSA. The antibiotic regimen was changed to include vancomycin but the ulcer continued to progress. Three days later, the ulcer had perforated and an emergent corneal patch graft was performed. To our knowledge, this is the first reported case of suture-related MRSA keratitis after uncomplicated clear corneal cataract surgery.Keywords: keratitis, MRSA, suture, staphylococcus aureus

  13. [Approaches for formation of the large bowel anastomoses for prophylaxis of their sutures insufficiency].

    Science.gov (United States)

    Militsa, N N; Postolenko, N D; Militsa, K N; Angelovski?, I N; Soldusova, V V; Kazakov, V S

    2014-11-01

    The results of surgical treatment of 424 patients, in whom the postponed and elective surgery was done for the large bowel malignancies, were analyzed. Advantages of a one-layer suture while formation of a large-bowel anastomoses in comparison with a two-layer suture were noted: minimal rate of the sutures insufficiency--(4.9 +/- 0.8)%, and (7.9 +/- 1.7)%, accordingly (p<0.001). Mostly often insufficience of the colorectal anastomosis sutures was observed after anterior rectal resection--in (9.7 +/- 1.9)% and (7.2 +/- 1.5)% patients. Postoperative lethality was 2.6%, for majority of the patients the reasons of the death were pulmonary thromboembolism and an acute cardio-vascu- lar insufficiency. PMID:25675738

  14. Tibial tubercle osteotomy for access during revision knee arthroplasty: Ethibond suture repair technique

    Directory of Open Access Journals (Sweden)

    Ghandour Adel

    2008-06-01

    Full Text Available Abstract Background Tibial Tubercle Osteotomy has shown much promise in revision total knee replacement. Methods of repair previously described include screw and wire fixation. Both methods have significant complications. Methods This article describes suture fixation of the osteotomy using Ethibond sutures placed medially with a lateral periosteal hinge. Results This method of fixation relies upon an adequate osteotomy segment including the entire insertion of the patella tendon. The lateral periosteal hinge is maintained and adds to the stability of the construct. A minimum of two number 5 Ethibond sutures are passed medially through drill holes to secure the osteotomy segment. No post-operative immobilisation is required. Conclusion Ethibond sutures provide adequate fixation of the tibial tubercle osteotomy segment in revision knee arthroplasty with reduced risk of complication as compared to conventional fixation methods.

  15. Treatment of thyroid ocular myopathy with adjustable and nonadjustable suture strabismus surgery.

    OpenAIRE

    Kraus, D J; Bullock, J. D.

    1993-01-01

    Our results pooled with those of others demonstrate a statistically significant improvement in outcome when adjustable sutures are implemented in the treatment of thyroid ocular myopathy. To our knowledge, this degree of significance has not been reported previously. We believe the value of adjustable suture strabismus surgery lies mainly in the prevention of large undercorrections and overcorrections. However, one cannot guarantee fusion or long-term alignment stability, especially without p...

  16. Comperative analysis of unilateral cleft lip closure using absorbable and nonabsorbable sutures: a randomised clinical study

    Directory of Open Access Journals (Sweden)

    Abhay Nilkanth Datarkar

    2014-09-01

    Full Text Available Aim: Patients with cleft lip usually undergo multiple procedures that require hospitalization resulting in emotional stress to their family members. Young patients often require sedation or general anesthesia (GA for suture removal on a sensitive area to prevent disruption of the repair. In this study, we compared absorbable and nonabsorbable sutures for primary cleft lip repair. Methods: Patients with cleft lip who presented to Smile Train Unit, Child Hospital and Research Institute, Nagpur, India, were randomly assigned to two groups and underwent surgical repair using either Vicryl Rapid suture (Group 1 or Prolene suture (Group 2. Patients were followed up at 1 month, 6 months, and 1 year. Photographs of the patients were obtained at these visits and rated using a validated 100-mm cosmesis visual analogue scale (VAS by three people (social worker, surgeon, and patient's mother. A VAS score of 15 mm or greater was considered as clinically important difference. Results: A total of 60 patients were enrolled in this study, and they were equally divided into two groups. There was no difference in age, race, sex, wound length, number of sutures, and layered repair rates between the groups. The average age of the patient was 3 months. There was no significant difference in the rates of infection which was 6% in this study, wound dehiscence, and hypertrophic scar formation. No significant difference was found in cosmetic outcome in both the mean VAS score of 90.3 in Group 1 and 91.7 in Group 2. Conclusion: Absorbable sutures are a viable alternative to nonabsorbable sutures in the repair of primary cleft lip repair. We prefer absorbable sutures because they do not require removal under GA or sedation.

  17. Stability of one-stage adjustable suture for the correction of horizontal strabismus.

    OpenAIRE

    Chow, P. C.

    1989-01-01

    One-stage adjustable suture for strabismus correction, with the whole operation done under topical anaesthesia and adjustment done on the table, was performed on 45 consecutive patients. The stability of the post-adjustment result was studied by comparing the post-adjustment deviation on the operating table to that at six weeks and three months after operation. The stability was comparable to that following the usual two-stage adjustable suture. The original angle of deviation and the fusion ...

  18. Sutural loosening and skeletal flexibility during growth: determination of drop-like shapes in sea urchins.

    OpenAIRE

    Johnson, Amy S.; Ellers, Olaf; Lemire, Jim; Minor, Melissa; Leddy, Holly A.

    2002-01-01

    The shape of sea urchins may be determined mechanically by patterns of force analogous to those that determine the shape of a water droplet. This mechanical analogy implies skeletal flexibility at the time of growth. Although comprised of many rigid calcite plates, sutural collagenous ligaments could confer such flexibility if the sutures between plates loosened and acted as joints at the time of growth. We present experimental evidence of such flexibility associated with weight gain and grow...

  19. Molecular basis of cranial suture biology and disease: Osteoblastic and osteoclastic perspectives

    OpenAIRE

    Beederman, Maureen; Farina, Evan M.; Reid, Russell R.

    2014-01-01

    The normal growth and development of the skull is a tightly regulated process that occurs along the osteogenic interfaces of the cranial sutures. Here, the borders of the calvarial bones and neighboring tissues above and below, function as a complex. Through coordinated remodeling efforts of bone deposition and resorption, the cranial sutures maintain a state of patency from infancy through early adulthood as the skull continues to grow and accommodate the developing brain's demands for expan...

  20. Surgical Sutures Filled with Adipose-Derived Stem Cells Promote Wound Healing

    OpenAIRE

    Reckhenrich, Ann Katharin; Kirsch, Bianca Manuela; Wahl, Elizabeth Ann; Schenck, Thilo Ludwig; Rezaeian, Farid; Harder, Yves; Foehr, Peter; Machens, Hans-gu?nther; Egan?a, Jose? Toma?s

    2014-01-01

    Delayed wound healing and scar formation are among the most frequent complications after surgical interventions. Although biodegradable surgical sutures present an excellent drug delivery opportunity, their primary function is tissue fixation. Mesenchymal stem cells (MSC) act as trophic mediators and are successful in activating biomaterials. Here biodegradable sutures were filled with adipose-derived mesenchymal stem cells (ASC) to provide a pro-regenerative environment at the injured site. ...

  1. Sealed sources in synthetic absorbable suture: a new method for permanent interstitial implantation

    International Nuclear Information System (INIS)

    Inactive gold grains are embedded at 1-cm intervals along a synthetic, absorbable surgical suture, then subjected to neutron irradiation in a nuclear reactor, forming a new material for permanent interstitial implant therapy. Assembling and activating the sealed sources in an absorbable carrier, the physical properties of the irradiated suture, its behavior in tissue, and the methods and results of implantation in the dog are described. (U.S.)

  2. A Novel Suture-Based Method for Efficient Transplantation of Stem Cells

    OpenAIRE

    Guyette, Jacques P.; Fakharzadeh, Michael; Burford, Evans J.; Tao, Ze-wei; Pins, George D.; Rolle, Marsha W.; Gaudette, Glenn R.

    2012-01-01

    Advances in regenerative medicine have improved the potential of using cellular therapy for treating several diseases. However, the effectiveness of new cellular therapies is largely limited by low cell engraftment and inadequate localization. To improve upon these limitations, we developed a novel delivery mechanism using cell-seeded biological sutures. Herein, we demonstrate the ability of cell-seeded biological sutures to efficiently implant human mesenchymal stem cells (hMSCs) to specific...

  3. A COMPARATIVE STUDY OF TWO SUTURE CONFIGURATIONS IN ZONE II FLEXOR TENDON REPAIR IN ADULTS

    OpenAIRE

    Navali, A. M.; Rouhani, A. R.; Mortazavi, J.

    2008-01-01

    Although the increase in the number of core sutures during flexor tendon repair increases the tensile strength of the repair, both increased handling at the time of repair and increased bulk at the repair site have been hypothesized as affecting clinical outcomes by increasing gliding resistance. The purpose of our study was to assess whether increasing the number of core sutures from two strands to four strands in zone II flexor tendon repair could improve the clinical results. A total of 42...

  4. Role of suture anchors in management of fractures of inferior pole of patella

    OpenAIRE

    Anand Ashish; Kumar Manish; Kodikal Gautam

    2010-01-01

    Background: The traditional recommendation for displaced comminuted inferior pole fractures is excision of the comminuted pole followed by reattachment of the patellar tendon with transosseous suture. To the best of our knowledge there has been no previous published study mentioning the use of suture anchors for fracture inferior pole of patella. We present a retrospective analysis of five cases of patients doing well at final follow-up of two years. Materials and Methods: Five patients tr...

  5. Learning curve of transumbilical suture-suspension single-incision laparoscopic cholecystectomy

    OpenAIRE

    Ming-Xin Pan; Zhi-Wei Liang; Yuan Cheng; Ze-Sheng Jiang; Xiao-Ping Xu; Kang-Hua Wang; Hai-Yan Liu; Yi Gao

    2013-01-01

    AIM: To investigate the learning curve of transumbilical suture-suspension single-incision laparoscopic cholecystectomy (SILC). METHODS: The clinical data of 180 consecutive transumbilical suture-suspension SILCs performed by a team in our department during the period from August 2009 to March 2011 were retrospectively analyzed. Patients were divided into nine groups according to operation dates, and each group included 20 patients operated on consecutively in each time period. The surgical o...

  6. Effect of particle size, coupling agent and DDGS additions on Paulownia wood polypropylene composites

    Science.gov (United States)

    The mechanical, flexural, thermal, and physical characteristics of wood plastic composites employing Paulownia wood (PP) flour derived from 36-mo-old trees blended with polypropylene (PP) were analyzed. Composites of 25% and 40% w/w of PW and 0-10% by weight of maleated polypropylene (MAPP) were pr...

  7. High-resolution solid-state NMR study of isotactic polypropylenes.

    Czech Academy of Sciences Publication Activity Database

    Fri?ová, O.; Uhrínová, M.; Hronský, V.; Koval'aková, M.; Ol?ák, D.; Chodák, I.; Sp?vá?ek, Ji?í

    2012-01-01

    Ro?. 6, ?. 3 (2012), s. 204-212. ISSN 1788-618X Institutional research plan: CEZ:AV0Z40500505 Keywords : material testing * metallocene isotactic polypropylene * Ziegler-Natta isotactic polypropylene Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.294, year: 2012

  8. Changes to the chemical structure of isotactic-polypropylene induced by ion-beam irradiation

    International Nuclear Information System (INIS)

    The chemical structures of various ion-beam irradiated isotactic-polypropylene samples were studied. Results of micro-Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy suggest not only the linear energy transfer, but also the fluence is effective in local transformation of the isotactic-polypropylene.

  9. Polypropylene mesh repair of a unilateral, congenital hernia in the inguinal region in a Thoroughbred filly

    OpenAIRE

    Moorman, Valerie J.; Jann, Henry W.

    2009-01-01

    A 2-day-old Thoroughbred intact female was presented for a large subcutaneous swelling in the right inguinal region. Surgical repair was performed using a double layer polypropylene mesh. To the authors’ knowledge, there have been no previous reports of surgical repair of congenital body wall hernias with polypropylene mesh in foals.

  10. Effect of Dietary Ascorbic Acid on Osteogenesis of Expanding Midpalatal Suture in Rats

    Science.gov (United States)

    Farhadian, Nasrin; Miresmaeili, Amirfarhang; Azar, Ramin; Zargaran, Massoumeh; Moghimbeigi, Abbas; Soheilifar, Sanaz

    2015-01-01

    Objectives: After maxillary expansion, a long period of retention is necessary to prevent early relapse. Therefore, it is beneficial to accelerate bone formation in the expanding midpalatal suture to reduce relapse. This study was designed to evaluate the effect of dietary vitamin C on osteogenesis of rat midpalatal suture during expansion. Materials and Methods: Fifty-four male Wistar rats were randomly divided into three groups, each with a control and an experimental subgroup. An open-loop spring was bonded to maxillary incisors of each animal to expand the premaxillary suture. Experimental groups received dietary vitamin C in their water. The rats in the three groups were sacrificed at three, nine or 17-day intervals after bonding the spring. Then, the premaxilla was dissected and sections were made and stained with hematoxylin and eosin and osteopontin marker. Osteoblasts and osteoclasts were counted in the suture. Two-way ANOVA and the Mann-Whitney-U test were used for analyzing the data. Results: After three days, the number of osteoblasts was significantly higher in the vitamin C group but after nine days it was significantly higher in the control group and after seventeen days there were no significant differences between the groups. Osteoclast counts were not significantly different between vitamin C and control groups. Conclusion: Vitamin C had a positive effect on osteogenesis at the beginning of bone formation in the expanding suture, but after nine days it had a negative effect on suture osteogenesis in rats.

  11. STUDY OF SKIN STAPLES AND CONVENTIONAL SUTURE FOR ABDOMINAL SKIN WOUND CLOSURE

    Directory of Open Access Journals (Sweden)

    S. S. Karbhari

    2012-07-01

    Full Text Available Introduction: The use of automatic stapling device for skin closure has become more popular due toits minimum disadvantages as compared to conventional suturing. Hence, this study was undertakento compare the time required for abdominal skin closure and pain during suture removal, between skinstaplers and conventional suture.Materials and Methods: The study includes 100 patients with age group of 45yrs-75yrs undergoingelective surgery, of which 50 patients underwent wound closure by staplers (Group-I and 50 patientsunderwent closure using prolene suturing (Group-II, during June 2009 to June 2011 at BasaweshwarTeaching and General Hospital, Gulbarga. Patients were randomly selected for conventional sutureand skin staple. Time duration for wound closure was recorded and pain scoring was given duringsuture removal, between both groups.Results and conclusion: In our study duration of wound closure was statistically significant(P<0.001 with staplers requiring lesser time than conventional prolene sutures, we also found thatpain during suture removal between both groups was statistically significant (P<0.001. We believethe advantages of speed and convenience of skin staples outweigh the extra cost, provided thedisposable instruments are reused until empty.

  12. Efficacy of Single-Suture Incision Closures in Tagged Juvenile Chinook Salmon Exposed to Simulated Turbine Passage

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, James W.; Deters, Katherine A.; Brown, Richard S.; Eppard, M. B.

    2011-09-01

    Reductions in the size of acoustic transmitters implanted in migrating juvenile salmonids have resulted in the use of a shorter incision-one that may warrant only a single suture for closure. However, it is not known whether a single suture will sufficiently hold the incision closed when fish are decompressed and when outward pressure is placed on the surgical site during turbine passage through hydroelectric dams. The objective of this study was to evaluate the effectiveness of single-suture incision closures on five response variables in juvenile Chinook salmon Oncorhynchus tshawytscha that were subjected to simulated turbine passage. An acoustic transmitter (0.43 g in air) and a passive integrated transponder tag (0.10 g in air) were implanted in each fish; the 6-mm incisions were closed with either one suture or two sutures. After exposure to simulated turbine passage, none of the fish exhibited expulsion of transmitters. In addition, the percentage of fish with suture tearing, incision tearing, or mortal injury did not differ between treatments. Expulsion of viscera through the incision was higher among fish that received one suture (12%) than among fish that received two sutures (1%). The higher incidence of visceral expulsion through single-suture incisions warrants concern. Consequently, for cases in which tagged juvenile salmonidsmay be exposed to turbine passage, we do not recommend the use of one suture to close 6-mm incisions associated with acoustic transmitter implantation.

  13. Performance Assessment of Suture Type, Water Temperature, and Surgeon Skill in Juvenile Chinook Salmon Surgically Implanted with Acoustic Transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Deters, Katherine A.; Brown, Richard S.; Carter, Kathleen M.; Boyd, James W.; Eppard, M. B.; Seaburg, Adam

    2010-05-01

    This study assessed performance of seven suture types in subyearling Chinook salmon Oncorhynchus tshawytscha implanted with acoustic microtransmitters. Nonabsorbable (Ethilon) and absorbable (Monocryl) monofilament and nonabsorbable (Nurolon, silk) and absorbable (Vicryl, Vicryl Plus, Vicryl Rapide) braided sutures were used to close incisions in Chinook salmon. Monocryl exhibited greater suture retention than all other suture types 7 d after surgery. Both monofilament suture types were retained better than all braided suture types at 14 d. Incision openness and tag retention did not differ among suture types. Wound inflammation was similar for Ethilon, Monocryl, and Nurolon at 7 d. Wound ulceration was lower for Ethilon, Monocryl, and Nurolon than for all other suture types at 14 d post-surgery. Fish held in 12°C water had more desirable post-surgery healing characteristics (i.e., higher suture and tag retention and lower incision openness, wound inflammation, and ulceration) at 7 and 14 d after surgery than those held in 17°C water. The effect of surgeon was a significant predictor for all response variables at 7 d. This result emphasizes the importance of including surgeon as a variable in telemetry study analyses when multiple surgeons are used. Monocryl performed better with regard to post-surgery healing characteristics in the study fish. The overall results support the conclusion that Monocryl is the best suture material to close incisions created during surgical implantation of acoustic microtransmitters in subyearling Chinook salmon.

  14. Physical and Mechanical Properties of Natural Fibers Filled Polypropylene Composites and Its Recycle

    Directory of Open Access Journals (Sweden)

    Myrtha Karina

    2007-01-01

    Full Text Available This study discusses the influence of natural fiber type on the performance of polypropylene and its recycle. Composites consisting of polypropylene (PP and natural fiber from wood (Acacia mangium, water hyacinth (Eichornia crassipes, kenaf (Hibiscus cannabinus, banana (Musa paradisiaca and empty fruit bunch of oil palm (Elaeis guineensis were prepared by extrusion and compression process based on the ratio of 50:50% (w/w with the addition of 2.5% polypropylene modified with maleic anhydride (MAPP. The effect of fiber type on the composites was evaluated. Physical and mechanical properties were studied. The composite showed significantly different properties based on the fiber type. Kenaf filled composite showed high tensile strength, break strain and modulus of elasticity properties but least absorbed water. Banana fiber filled propylene composite is comparable with that of kenaf. In general, recycle polypropylene can replace virgin polypropylene since their natural fibers filled composites showed similar mechanical and physical properties.

  15. Polypropylene Track Membranes for Mikro and Ultrafiltration of Chemically Aggressive Agents

    CERN Document Server

    Kravets, L I; Apel, P Yu

    2000-01-01

    A production process for track membranes on the basis of chemically resistant polymer polypropylene has been developed. Research in all stages of the formation of the polypropylene track membranes has been conducted: the main principles of the process of chemical etching of polypropylene irradiated with accelerated ions have been investigated, the most effective structure of the etchant for a selective etching of the heavy ion tracks has been selected, the parameters of etching have been optimized. A method for sensibilization of latent tracks in polypropylene by effect of solvents has been developed. It helps to reach a significant increase in etching selectivity. A method for destruction of an absorbed chromocontaining layer on the surface of polypropylene track membranes formed during etching has been elaborated. Experimental samples of the membranes for micro and ultrafiltration have been obtained and their properties have been studied in course of their exploitation in chemically aggressive agents. For t...

  16. Conversion of atactic polypropylene waste to fuel oil. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bhatia, J.

    1981-04-01

    A stable, convenient thermal pyrolysis process was demonstrated on a large scale pilot plant. The process successfully converted high viscosity copolymer atactic polypropylene to predominantly liquid fuels which could be burned in commercial burners. Energy yield of the process was very high - in excess of 93% including gas phase heating value. Design and operating data were obtained to permit design of a commercial size atactic conversion plant. Atactic polypropylene can be cracked at temperatures around 850/sup 0/F and residence time of 5 minutes. The viscosity of the cracked product increases with decrease in time/temperature. A majority of the pyrolysis was carried out at a pressure of 50 psig. Thermal cracking of atactic polypropylene is seen to result in sigificant coke formation (0.4% to 0.8% on a weight of feed basis) although the coke levels were of an order of magnitude lower than those obtained during catalytic cracking. The discrepancy between batch and continuous test data can be atrributed to lowered heat transfer and diffusion rates. Oxidative pyrolysis is not seen as a viable commercial alternative due to a significant amount of water formation. However, introduction of controlled quantities of oxygen at lower temperatures to affect change in feedstock viscosity could be considered. It is essential to have a complete characterization of the polymer composition and structure in order to obtain useful and duplicable data because the pyrolysis products and probably the pyrolysis kinetics are affected by introduction of abnormalities into the polymer structure during polymerization. The polymer products from continuous testing contained an olefinic content of 80% or higher. This suggests that the pyrolysis products be investigated for use as olefinic raw materials. Catalytic cracking does not seem to result in any advantage over the Thermal Cracking process in terms of reaction rates or temperature of operation.

  17. Tribological properties of polypropylene composites with carbon nanotubes and sepiolite.

    Science.gov (United States)

    Orozco, Victor H; Vargas, Andres F; Brostow, Witold; Datashvili, Tea; López, Betty L; Mei, Kevin; Su, Lisa

    2014-07-01

    Carbon nanotubes (CNTs) and sepiolite (SEP) were modified in order to improve their compatibility with the polypropylene (PP) matrix. Carboxylic groups were introduced into the CNTs through an oxidative treatment and aliphatic chains were incorporated on SEP by ion exchange of a cationic surfactant. Maleic anhydride grafted polypropylene (PPgMA) was mixed with neat PP to introduce polar groups into the polymer matrix. Composites including modified and non-modified fillers were prepared by melt extrusion. Dispersion and interaction of the CNTs with the PP and PPgMA matrices were evaluated by Raman spectroscopy while a focused ion beam/scanning electron microscopy (FIB/SEM) was used for SEP containing composites. Scratch resistance, microhardness, dynamic friction and wear were determined. Raman spectroscopy shows that the introduction of polar groups into PP matrices has a positive effect on the dispersion of modified CNTs. FIB/SEM results show that the modification of SEP improves its dispersion in the polypropylene matrix; filler clusters found in the PPgMA matrix are much times smaller than those in the neat PP. Despite of SEP agglomerates in the composites, a good interaction between both phases is seen; SEP particles are fully coated and embedded inside the PP matrix. The 'lack of cooperation' between unmodified PP and its fillers results in nanocomposites with larger residual depths; by contrast, PPgMA does 'cooperate' with its fillers so that the nanocomposites in scratch resistance testing have smaller residual depths R(h) than the neat PPgMA. Addition of the fillers to PPgMA also increases the hardness. As for wear rates, some our fillers provide higher and some lower wear rates than PP. PMID:24757963

  18. Use of polypropylene mesh in hernioplasty by Lichtenstein's technique

    International Nuclear Information System (INIS)

    INTRODUCTION. The aim of present study was to assess the benefit using the prosthesis (polypropylene mesh) in the hernioplasty using the Lichtenstein's technique in the 'Joaquin Albarran' Clinical Surgical Hospital. METHODS. A prospective study (with an interval of 14 months) was conducted in 140 surgical interventions carried out using the Lichtenstein's technique in patients presenting with inguinal hernia. One hundred and ten patients were excluded due to interventions were of ambulatory method. The following data were studied: type of hernia found in the physical examination, age, sex, and race, type of job, intervention's date, and technique used as well as the complications during the immediate postoperative time. Also, the hernia's relapse after operation, surgical complications and tolerance to polypropylene mesh were taking into account. RESULTS. There was predominance of male sex confirming a direct influence among types of jobs requiring a strong physical effort and the appearance of inguinal hernias (63,3 %). There were only three complications: a hematoma and two seromas. There were not relapses and any case of infection, both local and systemic. The use of prophylactic antibiotics showed an appropriate cost-benefit relationship. CONCLUSIONS. The old age, the male sex and a sustained physical effort have a directly proportional relation to appearance of inguinal hernias. The feasibility of Lichtenstein's hernioplasty, the null incidence of hernia relapsessty, the null incidence of hernia relapses and no appearance of complications including the rejection to prosthetic material, favoured the use of polypropylene in this plasty. Authors recommended the use of perioperative prophylactic antibiotic therapy to avoid wound's infection and thus to secure the result of surgical intervention and its durability. (author)

  19. Grafting polymerization of styrene onto preirradiated polypropylene fabric

    International Nuclear Information System (INIS)

    The grafting copolymerization of styrene onto polypropylene (PP) fabric has been studied by the preirradiation of gamma rays and electron beam, respectively. The PP fabric samples wee irradiated in the air and nitrogen gas individually. The effects of absorbed dose, styrene concentration in methanol, reaction temperature and reaction time on the degree of grafting were studied. Effects of storage time and temperature on the grafting rate were also observed. And a comparison of ?-ray and EB irradiation has been made. The results were reasonably interpreted by assuming that the grafting reaction was predominately initiated by trapped radicals

  20. Comparison of life cycle assessment for different volume polypropylene jars

    OpenAIRE

    Krki? Nevena M.; Lazi? Vera L.; Šuput Danijela Z.

    2012-01-01

    When deciding what packaging is the most appropriate for a product there are many factors to be considered. One of them is the impact of the packaging on environment. In this work, life cycle inventory and life cycle assessment of two different volume packagings were compared. The data were collected on the types and amounts of materials and energy consumption in the process of packaging and distribution of hand cream packed in polypropylene jars of 200 and 350 mL. Life cycle inventory ...

  1. ESR tomography of the postradiation oxidation of amorphous crystalline polypropylene

    International Nuclear Information System (INIS)

    The postradiation oxidation of amorphous-crystalline polypropylene, ?-irradiated at room temperature in the presence of oxygen, has been studied by ESR tomography. A method of analysis of the depth of destruction of the sample is proposed. The system of differential equations describing the process has been solved numerically, and the solutions obtained have been analyzed. The shape of the reaction front and the rate constant of the reaction R + O2 ? RO2 have been determined. The physiological meaning of the constant k1 is discussed

  2. Mechanical and Morphological Properties of Polypropylene/Polyoxymethylene Blends

    OpenAIRE

    Sirirat Wacharawichanant; Tanakorn Siripattanasak

    2013-01-01

    This work studies the mechanical and morphological properties of polypropylene (PP)/polyoxymethylene (POM) blends. The PP/POM blends were prepared by melting-blend with an internal mixer. The contents of PP were used at 10%, 20%, 30%, 70%, 80% and 90% by weight. The phase morphology of the blends was observed by scanning electron microscope (SEM) due to the mechanical properties depended on the phase morphology. The results show the decrease of the impact strength, Young’s modulus and tens...

  3. Morphology-mechanical Property Relationship of Polypropylene/starch Blends

    OpenAIRE

    C. H. Azhari; S. F. Wong

    2001-01-01

    The influence of morphology on mechanical property of several polypropylene/starch (PP/starch) blends of varying compositions was studied. The blends prepared were at wt%PP/wt%starch of 97.5/2.5, 95/5, 92.5/7.7, 90/10, 87.5/12.5 and 85/15. The morphology of the blends observed, using scanning electron microscopy showed them to be immiscible blends with distinct polymer-starch domains at high starch volume fractions (85%PP/15%starch-87.5%PP/12.5%starch), which gradually showed the morphology o...

  4. Electron-beam processing of wood fiber reinforced polypropylene

    International Nuclear Information System (INIS)

    A reactive extrusion procedure has been developed for wood fiber reinforced thermoplastic composites, applying a small amount of reactive additive that compatibilizes the synthetic and natural polymer components, with a subsequent Electron Beam treatment which is a productive method of creating active sites on both matrix polymer and fibrous reinforcement. Wood fiber and polypropylene (PP) bound together through reactive additive results in a composite which has not only a high modulus of elasticity, but also significantly higher flexural and tensile strength and improved thermal tolerance over the conventional wood fiber-PP blends, and over the PP itself. (author)

  5. Space Charge and Electrical Conduction Properties of Polypropylene Copolymer Films

    Science.gov (United States)

    Nakane, Emi; Kaneko, Kazue; Mori, Tatsuo; Mizutani, Teruyoshi; Takino, Hiroshi; Ishioka, Mitsugu

    We investigated the space charge and charging current characteristics in polypropylene copolymer films polymerized with metallocene and Ziegler-Natta catalysts, respectively. Positive and negative homo space charges were observed and their amounts showed maxima at 40 °C. Charge carriers injected from the semiconducting (SC) electrode were dominant at 60 °C. The copolymerization of ethylene enhanced the apparent carrier mobility and the charging current. Evaporated Al electrode showed much less carrier injection than Al plate or SC electrode (mechanically-contacted electrode). Carrier injection from SC electrode was dominant than that from Al plate. These suggest that the space charge formation depends on not only electrode materials but also contact conditions.

  6. Broadband terahertz spectroscopy of polypropylenes with different tacticities

    Science.gov (United States)

    Ariyoshi, S.; Hiroshiba, N.; Tanzawa, Y.; Ichikawa, Y.; Bae, J.

    2014-12-01

    We apply Fourier transform terahertz spectroscopy to an investigation of polypropylenes (PPs) with different tacticities. Terahertz (THz) absorption spectra were measured for isotactic, syndiotactic, and atactic samples over a frequency range of 1–11 THz. A clear difference in the spectra of the isotactic and syndiotactic PPs was observed, while that of the atactic PP did not display any clear characteristic absorption peaks. The spectral differences are thought to originate from not only the primary structure but also intermolecular vibrations of the well-packed PP-chains in the crystal structure. Broadband THz spectroscopy offers a nondestructive, noninvasive inspection technique for general-purpose plastics.

  7. Polypropylene/organoclay/SEBS nanocomposites with toughness-stiffness properties

    DEFF Research Database (Denmark)

    Sanporean (nee Potarniche), Catalina-Gabriela; Vuluga, Zina

    2014-01-01

    Polypropylene nanocomposites with a different amount of styrene-ethylene-butylene-styrene block copolymer (SEBS)/clay were prepared via a melt mixing technique. To improve the dispersion of commercial organoclay (denoted as OMMT), various amounts of SEBS were incorporated. At a fixed content of OMMT, the mechanical properties were improved with increasing SEBS content. The obtained nanocomposites were characterized through X-ray diffraction (XRD), differential scanning calorimetry (DSC-TG) and mechanical tests. The thermal-morphological-mechanical properties were investigated. The nanomaterials presented an improved decomposition temperature, a small decrease in tensile strength, a higher Young's modulus and a spectacular increase of 300% in impact strength.

  8. Radiation Damage of Polypropylene Fiber Targets in Storage Rings

    CERN Document Server

    Rohdjess, H; Bisplinghoff, J; Bollmann, R; Büsser, K; Diehl, O; Dohrmann, F; Engelhardt, H P; Eversheim, P D; Greiff, J; Gross, A; Gross-Hardt, R; Hinterberger, F; Igelbrink, M; Langkau, R; Maier, R; Mosel, F; Müller, M; Muenstermann, M; Prasuhn, D; Von Rossen, P; Scheid, H; Schirm, N; Schwandt, F; Scobel, W; Trelle, H J; Wellinghausen, A; Wiedmann, W; Woller, K; Ziegler, R

    2004-01-01

    Thin polypropylene (CH$_2$) fibers have been used for internal experiments in storage rings as an option for hydrogen targets. The change of the hydrogen content due to the radiation dose applied by the circulating proton beam has been investigated in the range $1\\cdot10^6$ to $2\\cdot10^8$~Gy at beam momenta of 1.5 to 3 GeV/c by comparing the elastic pp-scattering yield to that from inelastic p-carbon reactions. It is found that the loss of hydrogen as a function of applied dose receives contributions from a fast and a slow component.

  9. Study of irradiation effect on positronium formation in polypropylene

    International Nuclear Information System (INIS)

    6Co ?-rays and positron irradiation effect on positronium (Ps) formation in the bulk and near surface region of polypropylene (PP) was studied. It is revealed that the reduction of Ps formation probability in PP bulk as a function of elapsed time may not be due to enhanced concentration of oxygen groups, and should not be ascribed to a simple accumulation of free radicals. Results indicate that Ps in PP is not formed through only one branch. That branch sensitive to the irradiation as well as the existence of sample surface seems related to relatively mobile positrons

  10. Estudo comparativo, em cães, entre a anastomose esôfago-esofágica cervical em dois planos de sutura e a em um plano único extramucoso Study in dogs comparing esophagus-esophageal cervical anastomosis in two planes of suture versus a single extramucosal plane

    Directory of Open Access Journals (Sweden)

    Amaury José Teixeira Nigro

    1997-03-01

    Full Text Available O objetivo é comparar a eficácia entre as anastomoses esôfago-esofágicas cervicais em dois planos de sutura com as feitas em um plano único extramucoso. Utilizou-se 60 cães, sadios, sem raça definida, de ambos os sexos, com peso médio de 15 kg. Foram separados em dois grupos iguais: no GRUPO I será feita a anastomose em dois planos de sutura e, no GRUPO II, a em um plano único extramucoso. Cada grupo foi subdividido em 3 subgrupos iguais, e para cada um deles foi estabelecido um determinado período de observação pós-operatório (PO de 7, 14 e 30 dias, respectivamente. As suturas foram feitas sempre com fio de polipropileno 4 zeros. Avaliou-se a incidência de complicações pós-operatórias imediatas e tardias e às características histológicas da cicatrização de cada tipo de anastomose. A análise estatística dos dados coletados permitiu verificar que na anastomose esôfago-esofágica cervical executada em um plano único extramucoso a porcentagem de fistulas (13,6%, e de estenoses (30% ao nível da zona de sutura foi significantemente menor do que a observada na sutura realizada em dois planos de sutura em que as porcentagens foram de (26,7% e (63,4%, respectivamente. A cicatrização das estruturas da parede esofágica ao nível da anastomose também foi significantemente melhor na anastomose em plano único extramucoso do que na em dois planos de sutura. Os resultados observados permitiram concluir que a anastomose em plano único extramucoso é mais eficaz do que a executada em dois planos de sutura.The objective of our study was to compare the efficacy of two types of cervical esophagus-esophageal anastomoses: two planes of suture versus a single extramucosal suture. Sixty healthy mongrel dogs of both sexes with a medium body weight of 15 kg. Were separated into two groups. Group one: anastomosis using two planes of suture; and Group two: anastomosis using one plane of extramucosal suture. Each group was divided into three subgroups based on post-operative time periods: 7, 14 and 30 days. Polypropylene 4-0 sutures were used in all anastomoses. The incidence of early and late post-operative complications and histological characteristics of the healing process at the site of the anastomoses were evaluated. Statistical analyses of the data collected permitted verification that the cervical esophagus-esophageal anastomoses done by only the extramucosal suture showed an incidence of 13.6% fistula and 30% stenosis at the level of the suture zone, which was significantly lower as compared to that observed in the two plane suture repair group where the percentages were 26.7 and 63.4 respectively. The healing of the structure of the esophageal wall at the level of the anastomosis was also significantly improved in the single plane extramucosal anastomosis group as compared to the two plane suture group. The observed results permitted conclusion that the extramucosal anastomosis in a single plane is more effícacious than that executed in two suture planes.

  11. Deep suture zone in the North Barents Basin

    Science.gov (United States)

    Butsenko, Viktor; Kireev, Artem; Piskarev, Alexey; Savin, Vasily; Smirnov, Oleg

    2015-04-01

    Study of sedimentary basin evolution is a part of research for the forecast of oil and gas capacity of the North Barents shelf. Maps of potential fields anomalies are compiled on the basis of the latest geophysical databases, structural maps of the seismic horizons are analyzed, the location of sources of potential fields anomalies are calculated, 3D density and magnetic models of Earth's crust are constructed. Six seismic complexes are allocated in sedimentary cover structure: Devonian - Lower Carboniferous, Upper Carboniferous - Lower Permian, Mid Permian - Lower Triassic, Triassic - Lower Jurassic, Upper Jurassic - Lower Cretaceous, Lower Cretaceous - Quaternary. The research of lateral changes of allocated layers thickness gives an idea of sedimentation in the region on various time intervals. The structural and tectonic scheme of the region is made after analysis of new geologic-geophysical materials. Contact zones of heterogeneous blocks of the crystalline basement are marked, disjunctive dislocations in a sedimentary cover and the upper crust, and also zones of increase of sediments thickness in various seismic complexes are designated. The deep suture zone delimiting Mesozoic and Paleozoic sedimentary basins has the most important geological value among disjunctive zones of the region. This zone stretches along the Admiralty Arch in East part of the North Barents shelf and is marked by negative magnetic anomaly 30-50 km wide. In view of special tectonic value of the suture zone marked by this anomaly we have calculated the 3D magnetic crust model. The sedimentary layers of a model section is based on seismic data. As a result of modeling the studied anomaly of a magnetic field can be approximated by the block of basement rocks of the lowered magnetization (1.2 A/m). The surface of this block is located in a zone of anomaly at a depth of 12-14 km. The asymmetry of anomaly is accounted by an inclination to East of the borders of the block with low magnetization. Calculated basement magnetization is 1.9 A/m to the West from an anomaly zone that is a characteristic for many igneous and metamorphic rocks of the diorite composition. Magnetization of the basement formations sharply increases to 3.6 A/m to the East. Similar values of magnetization are characterized basalts and dolerites, and also many metamorphic rocks of the basic and ultrabasic composition. Thus, the simulated magnetic field anomaly not only corresponds to limits of the heterochronous sedimentary basins, but also shows the border between two heterogeneous basement blocks. "Bright spot" anomalies are marked out on seismic sections. Bright spots are mainly located near the zone of negative magnetic anomaly along the East part of the North Barents Basin. The AVO analysis of the anomalies of the seismic recording has allowed to allocate possible hydrocarbon reservoirs and to subdivide them into the gas-saturated and oil-gas-saturated.

  12. Técnica de suturas ajustables: Resultados Technique of adjustable sutures: Results

    Directory of Open Access Journals (Sweden)

    Lourdes R. Hernández Santos

    2001-06-01

    Full Text Available Se realizó un estudio sensorial y motor preoperatorio y posoperatorio a 84 pacientes que acudieron a la consulta de Visión Binocular con el diagnóstico de estrabismo horizontal a partir de los 13 años de edad. El método estadístico utilizado fue "t" o Chi cuadrado. Nos trazamos como objetivo determinar los resultados posoperatorios de la cirugía de estrabismo realizada con la técnica de suturas ajustables, que fueron los siguientes: el 61 % de los pacientes con exotropía y el 71,4 % con el diagnóstico de exotropía se encontraban en ortotropía a los 6 meses de la intervención. El 71,4 % de los pacientes con esotropía y el 83,3 % con el diagnóstico de esotropía se encontraban en ortotropía al año de la intervención. Esta técnica quirúrgica permite la modificación de la desviación en el posoperatorio inmediato.A preoperative and postoperative sensorial and motor study was conducted among 84 patients who received attention at the consultation room of Binocular Vision with the diagnosis of horizontal strabismus from the age of 13 years old on. The statistical method used was "t" or chi square test. Our objective was to determine the postoperative results of the strabismus surgery performed by the technique of adjustable sutures. The results were as follows: 61 % of the patients with exotropia and 71.4 % with the diagnosis of exotropia were in orthotropia 6 months after the operation. 71.4 % of the patients with exotropia and 83.3 % with the diagnosis of exotropia were in orthotropia a year after the operation. This surgical technique allows the modification of the deviation in the immediate postoperative.

  13. Comparison of CO2 laser welding with suture technique for repair of tendons

    Science.gov (United States)

    Popovic, Neven A.; Johnstone, Frederic L.; Kilkelly, Francis X.; McKinney, LuAnn; Van De Merwe, Willem P.; Smith, Allan C.

    1995-05-01

    The purpose of this study was to evaluate the efficacy, histology, and strength of laser welding in repair of sharply transected rat Achilles tendons. In 26 adult, male Sprague-Dawley rats, the severed tendons were repaired with a 7-0 nylon, modified Kessler core suture followed by either a running 9-0 nylon epitendinous suture or a circumferential CO2 laser epidendinous weld using 25% human albumin as a solder. All repairs were timed and post- operative tensile strength was analyzed with material testing equipment. In addition, histologic testing was performed on both types of repairs. The mean time to complete the epitendinous repair in the laser group was 3.5 minutes and in the suture group, 8 minutes. The mean ultimate tensile strength in 6 normal tendons was 40.9 Newtons (N) with group standard deviation of 5.2 N. When compared with normal controls, post-operatively both types of tendon repairs resulted in tensile failure at lower forces. The ultimate tensile strength for the epitendinous suture repair and the laser welds were 13% and 6% of normal controls, respectively. Twenty tendons with epidendinous suture repair had mean ultimate tensile strength of 5.4 (+/- 1.2) N, while the 17 tendons with laser wends failed at 2.6 (+/- 0.9) N. Histologic evaluation of tendons repaired with CO2 laser revealed areas of coagulation and edema on the surface of tendon edges. Post-operatively, greater tissue changes were noted in laser treated tendons than those repaired with sutures. Laser welding of epitenon is possible and can be completed faster than the suture repair. The repaired tendon surface appears smoother and less bulky after laser treatment. However, significantly decreased immediate post-operative strength was demonstrated by the use of Kruskal-Wallis one way analysis of variance and Turkey's pairwise comparison.

  14. Influence of suturing material on wound healing: Experimental study in dogs

    Directory of Open Access Journals (Sweden)

    Gazivoda Dragan

    2015-01-01

    Full Text Available Background/Aim. The most common materials implanted in the human organism are suture materials that are classified on the basis of several criteria, usually the origin, structure, and properties. The properties of suture materials are related to its absorbability and non-absorbability. When using resorbable materials it is of great importance to determine whether its absorbability and tensile strength help wound healing in function of time. Sutures themselves can become a source of inflammation, that may reduce or compromise the potential of reparation and regeneration. The aim of this experimental study on dogs was to ascertain whether the absorption rate and the degree of local tissue reactions differ from information provided by the manufacturers, whether there are differences between the applied suture materials and which of the used suture materials have better effect on wound healing. Methods. Experimental testing of the selected suture materials basic characteristics was performed on 6 German Shepherd dogs, which, after induction of general anesthesia, were made 3 identical incisions each in all 4 quadrants (left and right side of the upper and lower jaws, so that 12 horizontal incisions were formed, 10 mm long, 20-25 mm distant from one another, on each animal. Randomly, incisions were stitched up in the following order, starting from back to front: catgut, Dexon®, Vicryl-Rapid®. The experiment was terminated by histopathological examination of tissue samples, taken on postoperative day 3, 7, 14 and 21 in order to identify the effect of healing and the degree of local reaction. Results. The obtained results suggest that catgut has the highest absorption rate, while Dexon® the lowest. Vicryl-Rapid® causes the lowest level of local reactions, while Dexon® the highest. Conclusion. There is no ideal suture material because various patient factors also influence the wound healing process.

  15. Scalp swelling crossing the suture line on skull radiograph: is it always a sign of caput succedaneum?

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jae Woong; Lee, Chang Hee; Suh, Sang Il [Guro Hospital of Korea University, Department of Diagnostic Radiology, Seoul (Korea)

    2006-04-15

    Caput succedaneum is the soft swelling of the neonatal scalp that may extend over the suture line, as opposed to cephalhaematoma, which is restricted by the suture. However, if caput succedaneum and cephalhaematoma coexist and the swelling crosses the suture line, it may be diagnosed as caput succedaneum and the cephalhaematoma will be easily missed, both on the radiograph and clinically. We report an interesting MR finding in a neonate who simultaneously showed both caput succedaneum and cephalhaematoma. (orig.)

  16. Changes to the cell, tissue and architecture levels in cranial suture synostosis reveal a problem of timing in bone development

    OpenAIRE

    Regelsberger, J.; Milovanovic, P.; Schmidt, T.; Hahn, M.; Ea, Zimmermann; Tsokos, M.; Zustin, J.; Ro, Ritchie; Amling, M.; Busse, B.

    2012-01-01

    Premature fusion of cranial sutures is a common problem with an incidence of 3-5 per 10,000 live births. Despite progress in understanding molecular/genetic factors affecting suture function, the complex process of premature fusion is still poorly understood. In the present study, corresponding excised segments of nine patent and nine prematurely fused sagittal sutures from infants (age range 3-7 months) with a special emphasis on their hierarchical structural configuration were compared. Cel...

  17. Effect of traction sutures in the distal esophagus of the rat: a model for esophageal elongation by Foker's method

    OpenAIRE

    Lopes, M. F.; Catre?, D.; Cabrita, A.; Pires, A.; Patri?cio, J.

    2008-01-01

    This study aimed to evaluate a rat model of esophageal elongation using traction sutures by the Foker's method. After esophageal division and closure of the distal segment at approximately 4 mm from the cardia, traction sutures were placed for progressive stretching until the 7th postoperative day in the experimental group (n = 10), whilst no traction sutures were placed in the esophagus of the control group (n = 10). Clinical outcome as well as macroscopic and microscopic esophageal mor...

  18. Bundles of Spider Silk, Braided into Sutures, Resist Basic Cyclic Tests: Potential Use for Flexor Tendon Repair

    OpenAIRE

    Hennecke, Kathleen; Redeker, Joern; Kuhbier, Joern W.; Strauss, Sarah; Allmeling, Christina; Kasper, Cornelia; Reimers, Kerstin; Vogt, Peter M.

    2013-01-01

    Repair success for injuries to the flexor tendon in the hand is often limited by the in vivo behaviour of the suture used for repair. Common problems associated with the choice of suture material include increased risk of infection, foreign body reactions, and inappropriate mechanical responses, particularly decreases in mechanical properties over time. Improved suture materials are therefore needed. As high-performance materials with excellent tensile strength, spider silk fibres are an extr...

  19. LiquiBand® Surgical S topical adhesive versus sutures for the closure of laparoscopic wounds. A randomized controlled trial

    OpenAIRE

    Jan, Haider; Waters, Natasha; Haines, Pat; Kent, Andrew

    2013-01-01

    Cyanoacrylate adhesives offer the surgeon and patient an alternative to subcuticular suturing. LiquiBand® Surgical S (LBSS) is a new formulation with a blend of monomeric n-butyl and 2-octyl cyanoacrylates. In this study, the effectiveness, safety, and clinical utility of LBSS was compared to Vicryl™ sutures for the closure of laparoscopic incisions. This was a prospective randomized study of LBSS skin adhesive versus Vicryl™ sutures for the topical closure of laparoscopic surgical incis...

  20. Air gasification of polypropylene plastic waste in fluidized bed gasifier

    International Nuclear Information System (INIS)

    An experimental study on air gasification of polypropylene was conducted in a fluidized bed gasifier with an insider diameter (i.d.) of 100 mm and a height of 4.2 m. The effect of the equivalence ratio, bed height and fluidization velocity on various gasification results, including the product yield distribution, gas composition, gas heating value and gas yield were studied. The equivalence ratio appeared to have a significant effect on the reactor temperature and other gasification results. The increase of the equivalence ratio favored the formation of the fuel gas and decreased the formation of the tars and char. The decrease in the hydrocarbons content and, therefore, the gas heating value with an increase in the equivalence ratio were also observed. Both the bed height and the fluidization velocity seemed to have a small influence on the gasification results. The results obtained so far indicated that fluidized bed gasification of polypropylene with air could produce a fuel gas with a calorific value in the range of 5.2-11.4 MJ/N m3 and low tars content, which could be used in many end use applications

  1. Preparation and Characterization of Coir, Luffa Reinforced Polypropylene Composites

    Directory of Open Access Journals (Sweden)

    S.Tharaknath

    2014-10-01

    Full Text Available Natural fibres have been used to reinforce materials for over 3,000 years. More recently they have been employed in combination with plastics. Many types of natural fibres have been investigated for use in plastics including coir, luffa, flax, hemp, jute, sisal, and banana. Natural fibres have the advantages that they are renewable resources and have marketing appeal. These agricultural wastes can be used to prepare fibre reinforced polypropylene composites for commercial use. Application of composite materials to structures have presented the need for the engineering analysis this work focuses on the fabrication of polymer matrix composites by using natural fibres like coir, and luffa which are abundant nature in desired shapes by the help of various structures of patterns and calculating its material characteristics (tensile strength, flexural modulus, flexural rigidity, hardness number,% gain of water by conducting tests like tensile test, flexural test, hardness test, water absorption test, impact test, density test, sem analysis and their results are measured on sections of the material and make use of the natural fibre reinforced polypropylene composite material for automotive seat shell manufacturing.

  2. On engineering of properties of wood-polypropylene composite

    Directory of Open Access Journals (Sweden)

    ?iporovi? Milanka

    2006-01-01

    Full Text Available New materials based on wood have the advantage in the sense that their properties can be engineered so as to correspond to user demands. The properties which can be engineered are those relating both to their utilisation and machining, in particular - the tensile strength, elongation at break, modulus of elasticity and impact resistance. The research at the Faculty of Forestry and "Hipol" Chemical Industry related to the new type of wood-polypropylene composite. The content of wood filler was varied in the range between 40% and 70% mass contents of beech wood flour. After the highest tensile strength at 50% of filler content was determined, the effect of the wood filler origin was also examined at this content value. Therefore, wood flour of beech, poplar, acetylated pine and the waste MDF was used. The influence of the composition of the wood filler (beech combined with MDF, poplar and acetylated pine in comparison with pure polypropylene matrix was also examined, as well as the effect of the type of coupling agent. Hopefully, the results obtained in this study might serve as the initial data for production of easily machined high-strength composites.

  3. Morphology and properties of recycled polypropylene/bamboo fibers composites

    International Nuclear Information System (INIS)

    Polypropylene (PP) is among the most widely used thermoplastics in many industrial fields. However, like other recycled polymers, its properties usually decrease after recycling process and sometimes are degraded to poor properties level for direct re-employment. The recycled products, in general, need to be reinforced to have competitive properties. Short bamboo fibers (BF) have been added in a recycled PP (RPP) with and without compatibilizer type maleic anhydride polypropylene (MAPP). Several properties of composite materials, such as helium gas permeability and mechanical properties before and after ageing in water, were examined. The effects of bamboo fiber content and fiber chemical treatment have been also investigated. We showed that the helium permeability increases if fiber content is higher than 30% because of a poor adhesion between untreated bamboo fiber and polymer matrix. The composites reinforced by acetylated bamboo fibers show better helium permeability due to grafting of acetyl groups onto cellulose fibers surface and thus improves compatibility between bamboo fibers and matrix, which has been shown by microscopic observations. Besides, mechanical properties of composite decrease with ageing in water but the effect is less pronounced with low bamboo fiber content.

  4. Acoustic properties of polypropylene composites reinforced with stone groundwood

    Directory of Open Access Journals (Sweden)

    Joan Pere López

    2012-11-01

    Full Text Available Currently, acoustic isolation is one of the problems raised with building construction in Spain. The publication of the Basic Document for the protection against noise of the Technical Building Code has increased the demand of comfort for citizens. This has created the need to seek new composite materials that meet the new required acoustical building codes. In this paper we report the results of the newly developed composites that are able to improve the acoustic isolation of airborne noise. These composites were prepared from polypropylene (PP reinforced with mechanical pulp fibers from softwood (Pinus radiata. Mechanical and acoustical properties of the composites from mechanical pulp (MP and polypropylene (PP have been investigated and compared to fiberglass (FG composites. MP composites had lower tensile properties compared with FG composites, although these properties can be improved by incorporation of a coupling agent. The results of acoustical properties of MP composites were reported and compared with the conventional composites based on fiberglass and gypsum plasterboards. Finally, we suggest the application of MP composites as a light-weight building material to reduce acoustic transmitions.

  5. Investigation of Fibres Migration in Cotton/Polypropylene Blended Yarn

    Directory of Open Access Journals (Sweden)

    Dzmitry RYKLIN

    2014-09-01

    Full Text Available This study is devoted to theoretical and experimental research of fibres migration in blended yarns. A hypothesis states that due to fibres migration their tension in yarn becomes equal. On the basis of that hypothesis, we identified the factors that affect the migration. The main factors influencing are differences in Young's modulus and density of fibres. Simulating the fibres migration we obtained the formulae for determining the proportion of fibres in the external and inner layers of blended yarn. These formulae were proved by analysis of cross-section of cotton/polypropylene yarn. Results of blended yarn processing in knitting showed that migration of polypropylene fibres in direction to the yarn surface leads to significant increase of yarn breakages due to growth of its friction coefficient. Reduction of the input yarn tension by 10 % – 15 % helped to stabilize the process of knitting. It was found that the usage of theoretical information about fibres migration allows to draw conclusions about the necessity of adjustments to settings of subsequent processing of blended yarns. DOI: http://dx.doi.org/10.5755/j01.ms.20.3.4610

  6. Radiation Modification of Polypropylene Waste for Using as Electrolyte Membranes

    International Nuclear Information System (INIS)

    Graft copolymerization of styrene onto polypropylene (PP) and waste polypropylene (WPP) films has been carried out by means of ?-irradiation. The parameters may affect the grafting yield such as irradiation dose, type of solvent, inhibitor concentration, irradiation atmosphere and monomer concentration were optimized. The grafted films were then treated with chlorosulfonic acid to introduce sulfonic group as a high proton exchange moiety. The obtained membranes were characterized by using fourier transform infrared spectroscopy (FTIR), and studying their swelling behavior, thermal and mechanical properties. The electrical properties of the prepared membranes were evaluated as a function of degree of grafting, hydration number and their ionic conductivity. The results showed that the ionic conductivity of the WPP increases from 6 x 10-10 to 2.8 multiplication sign 10-2 S/ cm and for PP increases from 7x10-10 to 4.1x10-3 S/cm by changing the grafting degree. The chemical, physical and electrical characteristics of the prepared membranes recommend these membranes as potential candidate for proton exchange membrane fuel cell (PEMFC) applications

  7. Investigation of physical and chemical properties of polypropylene hybrid nanocomposites

    International Nuclear Information System (INIS)

    Highlights: ? Effect of morphology and properties of PP hybrid nanocomposites was investigated. ? Intercalated-exfoliated structures were in the system. ? Significant improvement of physical and chemical properties in hybrid nanocomposites. ? PP hybrid nanocomposites showed good thermal stability. -- Abstract: Hybrid nanocomposites fabricated based on an optimized physical and chemical properties modified polypropylene (PP)/polypropylene grafted maleic anhydride (PP-g-MA) with varied concentrations (1-7 wt% at a step of 2 wt%) of organoclay, montmorillonite (MMT). The morphology of the nanocomposites was studied by scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). It was found that partly intercalated and partly exfoliated structure (intercalated-exfoliated structures) existed in the system. The degree of exfoliation is a key factor to determine the reinforcement efficiency. The ratio of exfoliation to intercalation plays an important role in determining the properties of PP nanocomposites and only completely exfoliated silicate layers can significantly improve the properties. PP hybrid nanocomposites showed good thermal stability in the thermogravimetric analysis (TGA). Introduction of ?3% MMT in the nanocomposites increased the onset temperature of degradation by 27.5 oC compared to that of pure PP, while the 5 wt% MMT resulted the maximum hardness in these nanocomposites. The solvent resistance of PP hybrid nanocomposites slightly increased with increasing the clay content.

  8. Effects of suture position on left ventricular fluid mechanics under mitral valve edge-to-edge repair.

    Science.gov (United States)

    Du, Dongxing; Jiang, Song; Wang, Ze; Hu, Yingying; He, Zhaoming

    2014-01-01

    Mitral valve (MV) edge-to-edge repair (ETER) is a surgical procedure for the correction of mitral valve regurgitation by suturing the free edge of the leaflets. The leaflets are often sutured at three different positions: central, lateral and commissural portions. To study the effects of position of suture on left ventricular (LV) fluid mechanics under mitral valve ETER, a parametric model of MV-LV system during diastole was developed. The distribution and development of vortex and atrio-ventricular pressure under different suture position were investigated. Results show that the MV sutured at central and lateral in ETER creates two vortex rings around two jets, compared with single vortex ring around one jet of the MV sutured at commissure. Smaller total orifices lead to a higher pressure difference across the atrio-ventricular leaflets in diastole. The central suture generates smaller wall shear stresses than the lateral suture, while the commissural suture generated the minimum wall shear stresses in ETER. PMID:24211894

  9. TENSILE STRENGTH CHARACTERISTICS OF POLYPROPYLENE COMPOSITES REINFORCED WITH STONE GROUNDWOOD FIBERS FROM SOFTWOOD

    Directory of Open Access Journals (Sweden)

    Joan P. López,

    2012-06-01

    Full Text Available The behavior of stone groundwood / polypropylene injection-molded composites was evaluated with and without coupling agent. Stone groundwood (SGW is a fibrous material commonly prepared in a high yield process and mainly used for papermaking applications. In this work, the use of SGW fibers was explored as a reinforcing element of polypropylene (PP composites. The surface charge density of the composite components was evaluated, as well as the fiber’s length and diameter inside the composite material. Two mixing extrusion processes were evaluated, and the use of a kinetic mixer, instead of an internal mixer, resulted in longer mean fiber lengths of the reinforcing fibers. On the other hand, the accessibility of surface hydroxyl groups of stone groundwood fibers was improved by treating the fibers with 5% of sodium hydroxide, resulting in a noticeable increase of the tensile strength of the composites, for a similar percentage of coupling agent. A new parameter called Fiber Tensile Strength Factor is defined and used as a baseline for the comparison of the properties of the different composite materials. Finally the competitiveness of stone groundwood / polypropylene / polypropylene-co-maleic anhydride system, which compared favorably to sized glass-fiber / polypropylene GF/PP and glass-fiber / polypropylene / polypropylene-co-maleic anhydride composite formulations, was quantified by means of the fiber tensile strength factor.

  10. Investigation of the nanostructure and mechanical properties of polypropylene/polyamide 6/layered silicate ternary nanocomposites

    International Nuclear Information System (INIS)

    This work aims to investigate the structure-property relationship in ternary nanocomposites consisting of polypropylene as the matrix, nanoclay as the reinforcement and polyamide 6 as the intermediate phase. In this regard, composites of polypropylene/organoclay, polyamide/organoclay, blends of polypropylene/polyamide, and ternary nanocomposites of polypropylene/polyamide/layered silicate with and without compatibilizer were produced via melt compounding. Nanostructure was investigated by wide-angle X-ray diffraction and transmission electron microscopy. Scanning electron microscopy was employed to study the microstructure. Modulus of elasticity and yield strength were measured by uniaxial tensile test. Results show that silicate layers can only be observed inside polyamide particles. Moreover, polypropylene was unable to intercalate the grade of organoclay used in this study. While polyamide/organoclay system exhibited an exfoliated structure, the nanostructure of ternary nanocomposites was chiefly intercalated, due to the high concentration of silicate layers inside polyamide particles. Incorporation of organoclay into the polypropylene/polyamide system was seen to have a noticeable effect on the shape and size of polyamide particles. In addition, elastic modulus and yield strength were observed to be directly affected by incorporation of nanoclay and compatibilizer into the polypropylene matrix, respectively. The simultaneous presence of the two constituents in the system resulted in samples with superior mechanical properties in the elastic as well as the plastic deformation regime.

  11. Susceptibility to scratch surface damage of wollastonite- and talc-containing polypropylene micrometric composites

    International Nuclear Information System (INIS)

    The paper describes the effect of wollastonite and talc on the scratch deformation behavior of low and high crystallinity polypropylenes under identical test conditions. The vertical resolution of atomic force microscopy and lateral resolution of scanning electron microscopy is utilized to examine the characteristics of scratch damage. Contrary to the expectations that high crystallinity and stiffness of polypropylene composites should increase resistance to scratch deformation, the susceptibility to mechanical deformation depends on bonding of mineral particles to the polymer matrix. Scratch deformed regions in neat polypropylenes were free of voids and grooves, while reinforced-polypropylenes exhibited voids and debonding/detachment of filler particles. The severity of plastic deformation in reinforced polypropylenes is a function of debonding/detachment of mineral particles, which is comparatively more for talc-reinforced polypropylenes than wollastonite-reinforced polypropylenes because of the layered structure of talc that encourages delamination. Usage of coating and coupling agents improved the resistance to scratch deformation by promoting adhesion and bonding between the reinforcement and matrix

  12. Nuevo método de sutura subcutánea percutánea continua / New method of continuous percutaneous subcutaneous suture

    Scientific Electronic Library Online (English)

    Germán, Brito Sosa; Reinaldo, Echevarría Romero.

    2012-06-01

    Full Text Available Objetivos: realizar un método de sutura continua, en las personas operadas en el Hospital "Julio Trigo López", que disminuya los granulomas a nivel de la herida quirúrgica, y compararlas con el método tradicional. Métodos: se realizó un estudio experimental sobre la aplicación de un método de sutura [...] subcutánea percutánea continua, en un grupo de pacientes operados de diversas enfermedades, ya sea de urgencia, electivo o ambulatorio, en el Hospital "Julio Trigo López", en los años 2008 y 2009. Resultados: con el método de sutura subcutánea percutánea continua con nylon no se forman granulomas, mientras que con el método tradicional, sí ocurre en un porcentaje no despreciable. Las ventajas del método de sutura subcutánea percutánea continua con nylon son: en el plano celular subcutáneo de la pared abdominal no queda sutura, no se producen granulomas y es más económica. Conclusiones: la sutura de nylon es menos rechazada que la del cromado, ya que no se producen granulomas. El método de sutura subcutánea percutánea continua es una sutura más hemostática que el método tradicional, ya que el por ciento de hematomas es menor. El gasto económico es menor con el método de sutura subcutánea percutánea continua. Con el método de sutura subcutánea percutánea continua la sutura es extraída al 10mo. día de haberla aplicado. Abstract in english Objectives: to apply a continuous suture method to reduce granulomas in surgical wounds in patients operated on at "Julio Trigo Lopez" hospital, and to compare the results with those of the traditional method. Methods: an experimental study was conducted on the application of a continuous percutaneo [...] us subcutaneous suture in a group of patients operated on from several diseases, either under emergency, elective or outpatient conditions at "Julio Trigo Lopez" hospital during 2008 and 2009. Results: the continuous percutaneous subcutaneous suture method with nylon prevents formation of granulomas, whereas the traditional method did show a percentage of granulomas that is not small at all. The advantages of the former are the following: there is no suture left at subcutaneous cellular level of the abdominal wall, granulomas are absent and it is a more economic option. Conclusions: the nylon suture is less rejected than the chromated suture since granulomas do not appear. The continuous percutaneous subcutaneous suture method offers a more hemostatic suture than the traditional method, being the number of hematomas lower. The economic cost is reduced and the suture may be taken out ten days after surgery.

  13. Post operation recurrence of inguinal hernia in children and its relation with suture material

    Directory of Open Access Journals (Sweden)

    Omid Amanollahi

    2011-09-01

    Full Text Available Background: Using non-absorbable suture in children hernia repair to decrease of recurrence is recommended in the most pediatric surgery centers. The aim of this study was to determine relationship between kind of suture material and rate of hernia recurrence. Methods: In this clinical trial 200 children (age 1-5 years with inguinal hernia who operated in Imam-Reza Hospital (kermanshah –Iran Between April 2007 until April 2008 enrolled into the study. Cases were selected by convenience sampling method and then randomly divided into two groups (100 cases per group and operated with absorbable (silk 3-0 and non-absorbable (vicryli 3-0 suture material. Following period was 12 months after operation and collected data analyzed by statistical software. Emergency operations were excluded from the study.Results: 83% of patients were boy and 17% were girl. %53 showed right side inguinal, 29% left side and %18 were bilateral hernia. After one year follow up only one case of recurrence was observed in each group.Conclusion: Our study confirmed that recurrence of inguinal hernia in children after surgery, is not related to kind of suture material (absorbability and we didn’t find any significant difference. Other factors than suture material may influence recurrence rate of hernia operation in children.

  14. Vascular anomalies, sutures and small canals of the temporal bone on axial CT

    Energy Technology Data Exchange (ETDEWEB)

    Koesling, Sabrina [Department of Diagnostic Radiology, University of Halle, E. Grube Str. 40, 06097 Halle (Germany)]. E-mail: sabrina.koesling@medizin.uni-halle.de; Kunkel, Petra [Department of Diagnostic Radiology, University of Leipzig (Germany); Schul, Thomas [Department of Diagnostic Radiology, University of Leipzig (Germany)

    2005-06-01

    Purpose: Subtle bony structures, small canals and fine sutures cause sometimes problems in the analysis of CTs of the temporal bone. The aim of this study was: to analyze the visibility of subtle structures and to estimate the incidence of vascular anomalies. Patients and method: We retrospectively analyzed axial scans of 223 high-resolution CTs of the temporal bone obtained as single slice or spiral CT with 1 mm slice thickness. All CTs had clinical indications. Two experienced radiologists studied CTs regarding the visibility of the fine sutures, fissures and small canals and the occurrence of vascular anomalies. Results: The following structures were seen commonly: sphenosquamosal suture (76%), arcuate artery canal (93%), vestibular aqueduct (89%), mastoid emissary vein (82%), singular canal (56%). Not so commonly were observed: tympanosquamosal suture (31%), mastoid canaliculus (28%), lateral sigmoid sinus (28%), petrotympanic fissure (24%), tympanomastoid suture (10%). Seldom we identified: the inferior tympanic canaliculus (6%), high jugular bulb (6%), anterior sigmoid sinus (5%), dehiscent internal carotid artery canal (2%), persistent petrosquamosal sinus (1%), dehiscent jugular bulb (1%). Persistent stapedial artery, aberrant internal carotid artery, dehiscent jugular bulb, high jugular bulb with diverticulum, anterior and dehiscent sigmoid sinus were detected in below 1% of the analyzed temporal bones. The frequency of asymmetry of the jugular foramen, which varied between 3% and 42%, depended on different criterions of size. Conclusion: A profound knowledge of normal anatomy and anomalies of the temporal bone avoids misinterpretation as pathological lesions and iatrogenic bleedings.

  15. SUTURES USING POLYGLACTIN 910 AND TITANIUM STAPLES: URINARY AND UROLITHOGENIC ASPECTS IN EXPERIMENTAL ILEOCYSTOPLASTIES IN DOGS

    Directory of Open Access Journals (Sweden)

    Gabriela Silva Uchôa

    2011-12-01

    Full Text Available Urinary disorders are an important finding in ileocystoplasty, especially uroliths and crystalluria, and partly related to the type of suture material involved in this procedure. The aim of this study was to determine whether there are differences in the formation of uroliths and urinary crystalloid after ileocystoplasty in dogs, performed by suturing with nonabsorbable titanium staples and suture with polyglactin 910, noting their impact on renal function and urinary changes in the constitution difference in surgical time. Twelve healthy dogs were used and divided into two groups. In each animal was selected a segment of terminal ileum for bladder augmentation. In group A the suture of the detubelized ileal segment to the bladder was made with polyglactin 910 and in group B and the suture was made with titanium clips. We observed the presence of struvite crystals in 11 animals and the formation of large amounts of mucus in urine in all of them. In conclusion, no significant differences between groups in the formation of urinary crystals and uroliths after surgery, group A showed longer duration of surgery and no evidence of change in renal function in both groups.

  16. Study of polypropylene/polybutene blends modified by gamma irradiation and (high melt strength polypropylene)/polybutene blends

    International Nuclear Information System (INIS)

    It is well-known that polypropylene (PP) is difficult to process as a consequence of its linear structure. It is also known that grafting of long-chain branches on PP backbone using ionizing radiation is an effective approach to achieve high melt strength polypropylene (HMS PP). Chain-scission and, in minor extend, crosslinking and grafting are the predominant reaction in order to branch PP backbone. However, if multifunctional monomers are used to promote the grafting reaction, crosslinking can surpass chain scission and grafting, reducing drawability. Therefore, in an effort to enhance the processability and so the drawability, it has been found helpful to add a small amount of polybutene-1. Gamma irradiation technique was used to induce chemical changes in blends of PP and polybutene in acetylene atmosphere (crosslinker promoter) and in HMSPP/polybutene blends. The samples were irradiated with a 60Co source with doses of 12.5 and 20 kGy in the presence of acetylene. In this work, two different methods of blends processing were compared regarding rheological and mechanical properties. Effects on the strength and elongation at the yield point and at rupture were observed by mechanical tests and showed decrease of tensile strength and increase of elongation at rupture for samples obtained by irradiation of blends. The results from rheology demonstrated an increase in melt strength and drawability of blends

  17. Development of polypropylene/wood flour ecocomposites. Evaluation of silane as coupling agent

    International Nuclear Information System (INIS)

    The effects of Pinus Sylvestris wood flour as filler in polypropylene matrix was evaluated. The mechanical properties and the morphology of different wood flour/polypropylene composites (WPC) were studied. The composites materials were prepared with several amounts of wood flour from 10 to 30% wt. Mechanical properties show that the wood flour incorporation increases the rigidity of the composites. Morphological analysis indicates that agglomerates are formed, with amounts exceeding 30% of wood flour. For the silane--treated composites, the dispersion of the filler into the polypropylene (PP) matrix improved. Shore D hardness of the composites is decreased with the addition of the coupling agent.

  18. Comparison of rheological and mechanical properties of modified polypropylene - short glass fiber composites

    International Nuclear Information System (INIS)

    Short glass fiber (SGF) reinforced composite materials were principally fabricated using polypropylene (PP) as thermo-plastic matrix. Short glass fiber and polypropylene frequently suffer from lack of adequate fiber-matrix adhesion. This problem was addressed by grafting polypropylene (PP) with maleic anhydride (MA) in the presence of benzyl peroxide (BPO) as an initiator. The results revealed that by increasing fiber contents from 5 to 40 %, tensile strength increases while elongation at break decreases. Rheological behavior was found to be pseudoplastic, whereas viscosity increases by increasing SGF contents. A decrease in die swell was observed with increase in SGF contents. (author)

  19. Characterization of the I (|? |=1 ) -X 1?+(0 ,0 ) band of thorium oxide

    Science.gov (United States)

    Kokkin, Damian L.; Steimle, Timothy C.; DeMille, David

    2015-04-01

    The I (|? |=1 ) -X 1?+(0 ,0 ) band near 512 nm of thorium oxide has been recorded and analyzed field free and in the presence of both static electric and magnetic fields. The determined T00, B , and q field-free parameters for the I (|? |=1 )(v =0 ) state are (inc m-1 )19 539.3823 ±0.0003 ,0.328 69 ±0.000 03 , and 0.001 54 ± 0.000 05. The Zeeman-induced shifts and splittings of the low-J lines were analyzed to determine g factors and suggest that the I (|? |=1 )(v =0 ) state has a dominant 1? character. The Stark tuning of the low-J lines was analyzed to determine the permanent electric dipole moment ?el for the I (|? |=1 )(v =0 ) state of 4.25 ± 0.02 D.

  20. Changes in Latitude: A Chandra Study of G296.5+10.0

    Science.gov (United States)

    Slane, Patrick

    2014-09-01

    G296.5+10.0 is a supernova remnant at high Galactic latitude, with a distinctive bilateral morphology. Faraday rotation measurements provide evidence for a toroidal magnetic field component that may have been produced in a magnetic wind from the progenitor star. Gamma-ray observations indicate that the remnant has been an efficient particle accelerator. We propose Chandra observations of the remnant to search for evidence of the expected wind composition and density profile, and to determine the nature and spatial distribution of a hard spectral component. We will also investigate an apparent interaction with a small molecular cloud and search for X-ray emission corresponding to observed filamentary structure in the radio.

  1. Inflammatory reaction and tensile strength of the abdominal wall after an implant of polypropylene mesh and polypropylene/poliglecaprone mesh for abdominal wall defect treatment in rats

    Scientific Electronic Library Online (English)

    Maria de Lourdes Pessole, Biondo-Simões; Paula Almeida Pamponet, Moura; Kelly, Colla; Anna Flávia Zonato, Tocchio; Camila Gomes de, Morais; Renata Augusta de, Miranda; Rogério Ribeiro, Robes; Sérgio Ossamu, Ioshii.

    Full Text Available PURPOSE: To compare the inflammatory reaction and the growing resistance of the abdominal wall with the use of poliglecaprone meshes and polypropylene meshes associated with poliglecaprone in the correction of abdominal defects. METHODS: Seventy-seven Wistar rats were divided into three groups [...] : CG (non-operated animals: EG (polypropylene mesh) and UG (polypropylene and poliglecaprone mesh). A muscular and aponeurotic defect was formed and treated according to the group. Evaluations were made after 4, 7, 14, 28 and 56 days. The resistance and inflammatory pattern were studied. RESULTS: There was a gradual and significant gain in resistance, regularly in the EG and irregularly in the UG, which was lower on the 14th day (p=0.008). The inflammatory reaction was acute and more intense in the UG on the fourth day. At all other times, the inflammatory pattern was acute to chronic, similar in both groups, with minimum intensity on the 56th day. CONCLUSION: The greater resistance offered by the polypropylene mesh was regular and ascending, stabilizing on the 28th day, while that of the polypropylene/poliglecaprone was not even. In the end, the resistances were similar. The inflammatory response was greater in the UG on the fourth day and similar at all other times.

  2. Retention sutures in traumatic retinal detachment surgery complicated by absence of an irido-lenticular diaphragm

    Directory of Open Access Journals (Sweden)

    E. P. Gurmizov

    2014-07-01

    Full Text Available Purpose: to determine of the surgical approach at patients with traumatic retinal detachment complicated by absence of an irido- lenticular diaphragm.Methods: One-stage surgical treatment with use retention sutures at the patient with traumatic retinal detachment which have resulted a contusion of an eyeball, complicated by rupture on ceratotomic to notches with loss iris and a crystalline lens.Results: Carrying out retention sutures in surgery traumatic retinal detachment complicated by absence of an irido-lenticular diaphragm provides correct position of silicone in vitreal cavities.?onclusion: Retention sutures at the patient with traumatic retinal detachment at absence of an irido-lenticular diaphragm preventa silicone exit in the anterior chamber and development typical complications connected with it.

  3. Suture granuloma mimicking a recurrent sacro-coccygeal pilonidal sinus after Limberg flap.

    Science.gov (United States)

    Ardelt, Michael; Dittmar, Yves; Schulz, Birte; Rauchfuss, Falk; Scheuerlein, Hubert; Settmacher, Utz

    2014-12-01

    Sacro-coccygeal pilonidal sinus disease is classified as an asymptomatic, acutely abscess-forming or chronic subcutaneous inflammation in the sacro-coccygeal region featuring characteristic pits in the bottom cleft. Due to high rates of recurrence, two flap techniques have been established in the course of the past three decades. One of them is the Karydakis operation, the other option is a rotation flap named Limberg procedure. We report about a case of suture granuloma in the area of a Limberg flap after recurrent pilonidal sinus with extrusion of the suture material, thus mimicking recurrence. In case of recurrent pilonidal sinus following plastic coverage or primary closure, respectively, the differential diagnosis of suture granuloma should be considered. PMID:25124966

  4. Performance Assessment of Suture Type in Juvenile Chinook Salmon Surgically Implanted with Acoustic Transmitters

    Energy Technology Data Exchange (ETDEWEB)

    Deters, Katherine A.; Brown, Richard S.; Carter, Kathleen M.; Boyd, James W.

    2009-02-27

    The objective of this study was to determine the best overall suture material to close incisions from the surgical implantation of Juvenile Salmon Acoustic Telemetry System (JSATS) acoustic microtransmitters in subyearling Chinook salmon Oncorhynchus tshawytscha. The effects of seven suture materials, four surgeons, and two water temperatures on suture retention, incision openness, tag retention, tissue inflammation, and tissue ulceration were quantified. The laboratory study, conducted by researchers at the Pacific Northwest National Laboratory, supports a larger effort under way for the U.S. Army Corps of Engineers, Portland District, aimed at determining the suitability of acoustic telemetry for estimating short- and longer-term (30-60 days) juvenile-salmonid survival at Columbia and Snake River dams and through the lower Columbia River.

  5. Application of Self-retaining Bidirectional Barbed Absorbable Suture in Retroperito- neoscopic Partial Nephrectomy

    Scientific Electronic Library Online (English)

    Wang, Ke; Zhang, Yu-Lian; Lin, Chun-Hua; Liu, Dong-Fu; Men, Chang-Ping; Wang, Jian-Ming; Gao, Zhen-Li.

    2014-04-01

    Full Text Available ObjectiveTo investigate the safety and feasibility of self-retaining bidirectional barbed absorbable suture application in retroperitoneoscopic partial nephrectomy.Materials and MethodsFrom Sep 2011 and Aug 2012, 76 cases of retroperitoneoscopic partial nephrectomy were performed at our hospital. Th [...] e patients were divided into two groups: self-retaining barbed suture (SRBS) group (n = 36) and non-SRBS group (n = 40). There was no significant difference in age, sex, tumor size and location between the two groups. Clinical data and outcomes were analyzed retrospectively.ResultsAll 76 cases of retroperitoneoscopic partial nephrectomy were successfully performed, without conversion to open surgery or serious intraoperative complications. In the SRBS group, the suture time, warm ischemia time and operation blood loss were significantly shorter than that of non-SRBS group (p

  6. [Continuous suture in laparotomy using an absorbable eyelet thread according to the Smead Jones technique].

    Science.gov (United States)

    Ribero, F; Canino, V; Comotti, F; Ragusa, L

    1994-01-01

    In 78 patients undergoing laparotomy suturing was carried out using absorbable thread (polyglyconate - Maxon) with eyelet to obtain a continuous knot-free suture according to Smead Jones' technique. A prospective study was made of all surgical wounds three months after the operation to evaluate the reliability of this technique. On examination, wounds were fully healed in 98% of patients. Less than 2% of patients revealed infections, dehiscence or anomalous granulations of the wound. No laparocele were observed at the time of control using this method. Continuous suture using a trimethylene polyglyconate (Maxon) thread with eyelet according to the Smead Jones technique was found to be safe and effective. A follow-up after a longer interval will be performed in this group of patients in order to confirm these conclusions. PMID:7991177

  7. Light-guided localization within tissue using biocompatible surgical suture fiber as an optical waveguide

    Science.gov (United States)

    Choi, Woo June; Park, Kwan Seob; Lee, Byeong Ha

    2014-09-01

    In breast-conserving surgery, an optical wire is a useful surgical guiding tool to optically locate small lesions within the breast tissue. However, the use of a long silica glass fiber as the optical wire can be burdensome to patients because of its stiffness and nonbiocompatibility. We investigate the use of a biocompatible fiber for light localization in tissue. A surgical suture with a diameter of 400 ?m and a few centimeters long is employed as the biocompatible optical waveguide to transport the visible laser light to the inner tissue site. Optical location is confirmed with glow ball-like red laser illumination at the tip of the suture embedded within a fresh chicken breast tissue. Effective optical power coupling to the suture is made by using a double-cladding fiber coupler. From this preliminary result, we realize practical light localization with biopolymer waveguides.

  8. Scanning electron microscopy studies of needle and suture damage in rat carotid and femoral arteries.

    Science.gov (United States)

    Longa, E Z; Weinstein, P R; Chater, G

    1984-01-01

    Using the scanning electron microscope (SEM), we compared the areas of endothelial disruption 45 minutes after penetration of rat femoral and carotid artery walls with 75- and 100-mu taper point and taper cut microsurgical needles, with and without restoration of blood flow. Four experimental groups were designated: needle puncture only, single loose, suture loop, end-to-end anastomosis, and end-to-side anastomosis. The vessels were perfused with normal saline, immersed in 3% buffered glutaraldehyde, and mounted under slight tension to simulate physiological wall distention before SEM examination. Endothelial craters at vessel puncture sites were measured on SEM photomicrographs at 300 X magnification. All vessels were patent when examined. Crater diameters averaged less than double the needle size. Although taper cut needles produced craters that were 25% larger (P less than 0.05), vessel penetration was easier than with the taper point needle and bleeding times were the same. Suture loop produced craters that were 36% larger (P less than 0.05) than needle puncture alone. Craters were 20% larger when blood flow was restored and 50% larger in the femoral than in the carotid artery. Although craters seen after end-to-end anastomosis were not significantly larger than those after end-to-side anastomosis, interrupted sutures appeared to cause more endothelial damage than continuous sutures. These results suggest that the use of cutting needles, passage and tying of sutures, vessel distention by blood flow, and suturing of more muscular and less elastic vessel walls (femoral artery) may increase endothelial disruption but do not reduce patency. PMID:6392817

  9. Preliminary observation of extraocular muscles adjustable suture for partial accommodative esotropia surgery in children

    Directory of Open Access Journals (Sweden)

    Xiao-Lei Tang

    2014-04-01

    Full Text Available AIM:To investigate the efficacy of adjustable suture on partial accommodative esotropia surgery in children. METHODS: Thirty children with partial accommodative esotropia were treated by the recession of binocular medial rectus combined adjustable suture. The inclusion criteria were medium hypermetropia, and having wear sufficient degree mirror no less than six months, residual nonaccommodative esotropia deviation of +20? ? +35?. 3mm to 5mm recession of binocular medial rectus and 1mm to 2mm adjustable suture were kept in surgery. Suture was adjusted on the first day after surgery. The use of adjustable suture after surgery, deviation after surgery and binocular vision function were used to evaluate the efficacy during the follow up. RESULTS: Twenty-two children(73%were within orthotropia, 6 children deficient correction and 2 children excessive correction. After adjustment, all children(100%were within orthotropia. Residual strabismus degrees for 33cm and 6m were +5.9?±2.8?, +4.4?±4.3?, +3.8?±3.6?, +2.9?±3.5?, +2.7?±4.1? and +5.6?±3.2?, +4.0?±3.1?, +3.4?±3.4?, +2.5?±3.4?, +2.3?±3.9? 1-week, 1-month, 3-month, 6-month, 1-year after surgery respectively, without significant difference(P>0.05. Thirteen children(43%before surgery and 23 children(77%after surgery had binocular vision, with significant difference(PCONCLUSION: Adjustable suture perform operations can one-off correct partial accommodative esotropia more accurately, decrease the frequency of deficient correction and excessive correction efficiently.

  10. Radiation-induced oxidative degradation of isotactic polypropylene

    International Nuclear Information System (INIS)

    Gas evolution, oxygen consumption, and change of mechanical properties were studied for the ?-ray irradiation of isotactic polypropylene from 60Co under various conditions, such as vacuum, air, and oxygen at room temperature. For irradiation under vacuum, G(H2) = 2.9 and G(CH4) = 0.09; the G values for other gases were very small. In the presence of oxygen, G(H2) was the same, and the G values for other hydrocarbons were two times those under vacuum. The G values of oxidative products and oxygen consumption were G(CO2) = 2.5, G(CO) = 1.1, and G(O2) = 50 at oxygen pressure of 500 torr and were dependent on oxygen pressure. With irradiation under vacuum at 2 to 3 Mrad, mechanical properties scarcely changes immediately after irradiation but degrade gradually with storage time in air at room temperature

  11. Surface treated polypropylene (PP) fibres for reinforced concrete

    International Nuclear Information System (INIS)

    Surface treatments on a polypropylene (PP) fibre have contributed to the improvement of fibre/concrete adhesion in fibre-reinforced concrete. The treatments to the PP fibre were characterized by contact angle measurements, ATR-IR and XPS to analyse chemical alterations. The surface topography and fibre/concrete interaction were analysed by several microscopic techniques, namely optical petrographic, and scanning electron microscopy. Treatment modified the surface chemistry and topography of the fibre by introducing sodium moieties and created additional fibre surface roughness. Modifications in the fibre surface led to an increase in the adhesion properties between the treated fibres and concrete and an improvement in the mechanical properties of the fibre-reinforced concrete composite as compared to the concrete containing untreated PP fibres. Compatibility with the concrete and increased roughness and mineral surface was also improved by nucleated portlandite and ettringite mineral association anchored on the alkaline PP fibre surface, which is induced during treatment

  12. Surface treated polypropylene (PP) fibres for reinforced concrete

    Energy Technology Data Exchange (ETDEWEB)

    López-Buendía, Angel M., E-mail: buendia@uv.es [AIDICO Technological Institute of Construction, Benjamin Franklin 17, 46380 Paterna, Valencia (Spain); Romero-Sánchez, María Dolores [AIDICO Technological Institute of Construction, Marble Technical Unit, Camí de Castella 4, 03660 Novelda. Alicante (Spain); Climent, Verónica [Lafarge Cementos, Polígono Sepes, Isaac Newton s/n, 46500 Sagunto, Valencia (Spain); Guillem, Celia [AIDICO Technological Institute of Construction, Marble Technical Unit, Camí de Castella 4, 03660 Novelda. Alicante (Spain)

    2013-12-15

    Surface treatments on a polypropylene (PP) fibre have contributed to the improvement of fibre/concrete adhesion in fibre-reinforced concrete. The treatments to the PP fibre were characterized by contact angle measurements, ATR-IR and XPS to analyse chemical alterations. The surface topography and fibre/concrete interaction were analysed by several microscopic techniques, namely optical petrographic, and scanning electron microscopy. Treatment modified the surface chemistry and topography of the fibre by introducing sodium moieties and created additional fibre surface roughness. Modifications in the fibre surface led to an increase in the adhesion properties between the treated fibres and concrete and an improvement in the mechanical properties of the fibre-reinforced concrete composite as compared to the concrete containing untreated PP fibres. Compatibility with the concrete and increased roughness and mineral surface was also improved by nucleated portlandite and ettringite mineral association anchored on the alkaline PP fibre surface, which is induced during treatment.

  13. Elongational Flow-induced Crystallization in Polypropylene/Talc Nanocomposites

    Science.gov (United States)

    khalil, Mouhamad; hébraud, Pascal; Mcheik, Ali; Mortada, Houssein; Lakis, Hassan; Hamieh, Tayssir

    During the processing of the polymers, macromolecules undergo a significant flow just before or during cooling. For semi-crystalline materials, the flow widely influences both the crystallization kinetics and the resulting crystalline orientation. Moreover, in the presence of nucleating filler, even more with a high aspect ratio, these phenomena of crystallization under elongational conditions can be disrupted. In this study, melt blended nanocomposites of PP /Talc were processed using an internal mixer. An elongational rheometer was used to generate well controlled different extensional flow conditions. Samples were then characterized by WAXS to reveal and quantify the fillers and PP crystalline phase orientation. Crystalline orientation of polypropylene was found to be strongly affected by the addition of Talc under extensional flow and the Talc orientation.

  14. Use of Cellulose-Containing Fillers in Composites with Polypropylene

    Directory of Open Access Journals (Sweden)

    Marina TAVROGINSKAYA

    2011-07-01

    Full Text Available The composites, containing recycled polypropylene and fillers, obtained from different lignocellulosics by the thermocatalytic destruction method, were investigated. Birch sawdust, newsprint wastes, cotton residues and wood bleached sulphate pulp were used as raw materials for obtaining fillers. The indices of mechanical properties (tensile strength, modulus of elasticity, deformation at break, shear modulus, toughness, twisting moment of the composites' samples were determined. It has been found that the obtained composites have relatively good mechanical properties. Better results were obtained, using fillers from sawdust and wood pulp. After treating the fillers with rapeseed oil, their water vapour sorption and water retention value (WRV decreased. In this case, the strength of the composites was higher.http://dx.doi.org/10.5755/j01.ms.17.2.484

  15. Conifer fibers as reinforcing materials for polypropylene-based composites

    DEFF Research Database (Denmark)

    Plackett, David; Chengzhi, Chuai

    2001-01-01

    Conifer fibers were used to reinforce polypropylene (PP). To improve the compatibility between the conifer fibers and the PP matrix, the fibers were either grafted with maleated PP (MAPP), treated by adding MAPP, or mixed with ethylene/propylene/diene terpolymer (EPDM). The treatments resulted in improved processing, as well as improvements in the thermal and mechanical properties of the resultant composites compared with the composites filled with untreated conifer fibers. Moreover, MAPP grafting and MAPP treating displayed more obvious benefits than EPDM treating in terms of thermal properties, processing flowability, and tensile strength improvements. EPDM treating also produced more significant benefits than either MAPP grafting or MAPP treating in terms of impact strength and tensile elongation improvements. These improvements were attributed to surface coating of the fibers when EPDM was used. In addition, the effect of the concentration of the conifer fibers on the properties of the composites and the difference between MAPP grafting and MAPP treating were evaluated.

  16. Aqueous Processes for Dyeing Generic, Unmodified Polypropylene Fiber

    Directory of Open Access Journals (Sweden)

    Murari L. Gupta

    2010-06-01

    Full Text Available Acid leuco vat dyeings of polypropylene (PP fabrics in combinations of a trichromatic series of colorants (red, yellow and blue plus an orange were performed in order to determine the compatibility of the component colorants in the developed single stage, batch exhaust dyeing process reported earlier. Cross-section micrographs of dyed fibers revealed the absence of "ring-dyeing". Tensile tests and X-ray crystallinity results confirmed that the developed dyeing process did not significantly alter the tensile strength and modulus of the dyed PP textiles. PP fabrics dyed with simulated, continuous acid vat dyeing processes (pad-steam and pad-dry heat demonstrated good color yields and levelness with adequate fastness to crocking, washing and dry cleaning.

  17. Effects of the Biodegradation on Biodegradable Polymer Blends and Polypropylene

    Science.gov (United States)

    Pereira, R. C. T.; Franchetti, S. M. M.; Agnelli, J. A. M.; Mattoso, L. H. C.

    2008-08-01

    The large use of plastics in the world generates a large amount of waste which persists around 200 years in the environment. To minimize this effect is important to search some new polymer materials: the blends of biodegradable polymers with synthetic polymers. It is a large area that needs an intensive research to investigate the blends properties and its behavior face to the different treatments to aim at the biodegradation. The blends used in this work are: some biodegradable polymers such as: poly(hydroxybutyrate) (PHB) and poly(?-polycaprolactone) (PCL) with a synthetic polymer, polypropylene (PP), in lower concentration. These blends were prepared using an internal mixer (Torque Rheometer), and pressed. These films were submitted to fungus biotreatment. The films analyses will be carried out by Fourier Transform Infrared (FTIR), UV-Vis absorption (UV-Vis), Scanning Electronic Microscopy (SEM), DSC and TGA.

  18. Packing parameters effect on injection molding of polypropylene nanostructured surfaces

    DEFF Research Database (Denmark)

    Calaon, Matteo; Tosello, Guido

    2012-01-01

    In today´s industry, applications involving surface patterning of sub-?m to nanometer scale structures have shown a high growth potential. To investigate the injection molding capability of replicating sub-?m surface texture on a large scale area, a 30x80 mm2 tool insert with surface structures having a diameter of 500 nm was employed. The tool insert surface was produced using chemical-based-batch techniques such aluminum anodization and nickel electroplating. During the injection molding process, polypropylene (PP) was employed as material and packing phase parameters (packing time, packing pressure) were investigated. The replicated surface topographies were quantitatively characterized by atomic force microscopy using specific three-dimensional surface parameters and qualitatively inspected by scanning electron microscopy. Results showed that the degree of replication from the tool to the polymer part was mainly influenced by packing pressure level and distance from the gate.

  19. Biocomposites from co-polypropylene and distillers' grains

    Science.gov (United States)

    Zarrinbakhsh, Nima; Mohanty, Amar K.; Misra, Manjusri

    2015-05-01

    In the present work, we have explored the polymeric composites of distillers' grains with co-polypropylene (co-PP). The effect of maleated-PP compatibilizer on mechanical, thermomechanical and physical properties was evaluated. The composite materials were produced by melt extrusion in a micro-compounder followed by injection molding in a micro-injection machine. The composites were characterized for their tensile, flexural and impact properties. Also, melt flow index and heat deflection temperature were measured. The results showed more than 30 % improvement in modulus when comparing the compatibilized biocomposite with neat co-PP. Also, the strength of the compatibilized biocomposite measured in tensile and flexural tests was comparable to or even better than that of the neat matrix. On the other hand, the reduced flexibility and toughness as a result of compatibilization were in an acceptable range. The biocomposites showed more rigidity at elevated temperatures. The produced distillers' grain biocomposites showed promises for industrial applications.

  20. Thermal degradation and viscoelasticity of polypropylene-clay nanocomposites

    CERN Document Server

    Drozdov, A D; Drozdov, D A; Gupta, R K

    2003-01-01

    Results of torsional oscillation tests are reported that were performed at the temperature T=230C on melts of a hybrid nanocomposite consisting of isotactic polypropylene reinforced with 5 wt.% of montmorillonite clay. Prior to mechanical testing, specimens were annealed at temperatures ranging from 250 to 310C for various amounts of time (from 15 to 420 min). Thermal treatment induced degradation of the matrix and a pronounced decrease in its molecular weight. An integro-differential equation is derived for the evolution of molecular weight based on the fragmentation-aggregation concept. This relation involves two adjustable parameters that are found by fitting observations. With reference to the theory of transient networks, constitutive equations are developed for the viscoelastic response of nanocomposite melts. The stress-strain relations are characterized by three material constants (the shear modulus, the average energy for rearrangement of strands and the standard deviation of activation energies) tha...

  1. Raman Spectra and Mechanical Properties of Graphene/Polypropylene Nanocomposites

    Directory of Open Access Journals (Sweden)

    Siti R. Ahmad

    2015-02-01

    Full Text Available Graphene/Polypropylene nanocomposites were prepared at different filler loading and different average surface diameter 5, 15 and 25?m of graphene nanoplatelets by using Haake Minilab mixer at 180oC and rotor speed 50rpm. Besides, Haake MiniJet is used to obtain dumbbell shape specimen. The effect of filler loading and average surface area of filler in PP/GnP composites on Raman spectrum and tensile properties were studied. Raman spectrum of graphene particles indicate three major spectrums such as D, G and 2D band. In addition, PP/GnP composites shows the Raman band shift quite strong by increasing GnP loading. In general, increased of graphene nanoplatelets loading have increased the value of modulus of elasticity, whereas tensile strength, elongation at break of composites reduced

  2. Manufacturing Flax Fibre-Reinforced Polypropylene Composites by Hot-Pressing

    Science.gov (United States)

    Jolly, Marc; Jayaraman, Krishnan

    The renewable characteristic of natural fibres, such as flax, and the recyclable nature of thermoplastic polymers, such as polypropylene, provide an attractive eco-friendly quality to the resulting composite materials. Common methods for manufacturing natural fibre-reinforced thermoplastic composites, injection moulding and extrusion, tend to degrade the fibres during processing. Development of a simple manufacturing technique for these composites, that minimises fibre degradation, is the main objective of this study. Flax fibres were conditioned, cut into lengths ranging from 1 mm to 30 mm with scissors and a pelletiser, and shaped into randomly oriented mats using a drop feed tower. Polypropylene in sheet form, was added to the fibres to furnish polypropylene/flax/polypropylene sandwiches with a fibre mass fraction of 25%, which were then consolidated by the hot pressing technique. Tensile, flexural and impact properties of these composite sheets were determined as functions of fibre length and processing temperature.

  3. Long-term stability of irradiated polypropylene fibers and carboxylic cationites on their base

    International Nuclear Information System (INIS)

    Study is carried out of polypropylene fibers and fibrous carboxylic cationites on their base, which have been obtained by radiation graft polymerization of acrylic acid by the method of preliminary irradiation of polypropylene fibers on air (gamma-rays of 60Co, dose rate 0.37 Gy/s, dose 5-140 kGy). Mechanical and sorptive properties of polypropylene fibers and cationites are investigated after long-term storage in different conditions. The cationite obtained has excellent sorption properties towards cations of Cd, Pb, Cu. Zn, Fe and etc. It is shown that conditions of graft polymerization and storage influence on long-term stability of carboxylic cationites on the base of polypropylene fibers. It is pointed out that the use of cross-linking agent considerably increases long-term stability of grafted fibers

  4. Physical and dielectric properties of irradiated polypropylene and poly(ethylene terephthalate)

    International Nuclear Information System (INIS)

    The effect of high-energy electron irradiation in air and in nitrogen on the physical and dielectric properties of polypropylene and poly(ethylene terephthalate) has been studied by measurements of electric strength, dielectric constant, dissipation factor, tensile strength, gel fraction and molecular weight distribution. Electric strength of polypropylene was improved by irradiation, while dielectric properties of poly(ethylene terephthalate) were virtually unaffected by irradiation of 1.0-20 Mrad. Possible mechanisms for increasing electric strength are discussed from the point of view of degradation and oxidation taking place simultaneously with crosslinking of polypropylene. The maximum dose level to improve the electric strength of polypropylene is determined to be about 5 Mrad. (author)

  5. Radical termination rate constants and mechanical properties of ?-irradiated isotactic polypropylene with some additives

    International Nuclear Information System (INIS)

    Isotactic polypropylene saturated with hexadecane and hexadecene-1, were irradiated in air and vacuum, their ESR spectra were examined, and the reaction constants for radical termination were compared with those of polypropylene without additives. Mechanical properties of ?-irradiated samples with and without additives were measured after post-irradiation aging periods up to two months in oxygen atmosphere. The mechanical properties of polypropylene with the additives were found to be better than those without. Although the unsaturated additive decreases the rate of post-irradiation oxidation of the radicals, the effects on the mechanical properties of irradiated and aged polypropylene caused by the two additives is about the same. The relation between the radical yields, the termination rate constants, and the mechanical properties is discussed. (author)

  6. Analysis of Flexural Strength for Steel, Glass and Polypropylene Fiber Reinforced Concrete

    OpenAIRE

    Chapala. Venkata x Venkata Ramana; CH. Naga Sindhura

    2012-01-01

    This analysis study is done by using different types of fibres such as steel, glass and polypropylene with aspect ratio varying from 20 to 120 for steel, 600 to 860 for glass and 30 to 100 for polypropylene fibres.The total fibre percentages of 0 to 2?0for steel, 0 to 2?0for glass and 0 to 2.5?0for polypropylene with variation of 0.25?he design mix varying from M20 to M60 with water cement ratio 0.3 to 0.55 for steel, 0.16 to 0.55 for glass and 0.46 for polypropylene.After being cured...

  7. Effect of processing conditions on the mechanical and thermal properties of high-impact polypropylene nanocomposites

    International Nuclear Information System (INIS)

    Highlights: ? Polypropylene montmorillonite (PP-MMT) produced at different processing conditions. ? Polypropylene Nanocomposites with higher increase on impact resistance. ? Higher enhancement on mechanical properties. - Abstract: Polypropylene montmorillonite (PP-MMT) nanocomposites have been prepared by using a co-rotating twin screw extruder. The effects of processing conditions at fixed clay content (5 wt%) on polymer properties were investigated by means of transmission electron microscopy (TEM), flexural modulus, izod impact, dynamic mechanical analysis (DMA), and differential scanning calorimetry (DSC). It was noticed that the morphology and the mechanical properties of polypropylene nanocomposites were affected by different screw shear configuration. The results showed that the higher enhancement on mechanical properties was obtained by medium shear intensity profile instead of high configuration. An exceptional increase (maximum of 282%) on impact resistance was observed.

  8. Microbiopsy engineered for minimally invasive and suture-free sub-millimetre skin sampling

    OpenAIRE

    Lin, Lynlee L.; Prow, Tarl W.; Raphael, Anthony P.; Harrold Iii, Robert L.; Primiero, Clare A.; Ansaldo, Alexander B.; Soyer, H. Peter

    2013-01-01

    We describe the development of a sub-millimetre skin punch biopsy device for minimally invasive and suture-free skin sampling for molecular diagnosis and research. Conventional skin punch biopsies range from 2-4 mm in diameter. Local anaesthesia is required and sutures are usually used to close the wound. Our microbiopsy is 0.50 mm wide and 0.20 mm thick. The microbiopsy device is fabricated from three stacked medical grade stainless steel plates tapered to a point and contains a chamber with...

  9. Necrobiotic palisading suture granulomas involving bone and joint: report of two cases.

    Science.gov (United States)

    Marcus, V A; Roy, I; Sullivan, J D; Sutton, J R

    1997-05-01

    Biomaterial used in surgery is relatively inert and non-toxic; however, adverse reactions may follow implantation of such foreign material. We describe the first two cases of bone and joint destruction by necrobiotic palisading suture granulomas. The hypersensitivity reaction occurred years after shoulder repair using silk sutures. One patient received chemotherapy for a mistaken diagnosis of tuberculous arthritis. Although very rare, foreign material should be included in the differential diagnosis of necrotizing granulomas. A history of surgery and microscopic examination with polarized light should allow recognition of this entity. PMID:9158681

  10. Randomised controlled study of two different techniques of skin suture in endoscopic release of carpal tunnel

    DEFF Research Database (Denmark)

    Hansen, Torben Bæk; Kirkeby, Lone

    2009-01-01

    In a prospective, randomised trial of 54 hands in 47 patients incisions were randomised to be closed by either absorbable subcuticular (polyglytone 6211, Caprosyn), or non-absorbable interrupted (polybutester, Novafil), sutures after single-portal endoscopic release of the carpal tunnel. There was a significant reduction in pain scores on days 1 and 2 in the patients treated with an absorbable continuous subcuticular suture, and no difference in inflammation or infection. There was no difference in the cosmetic appearance between the two groups after three months.

  11. Suture Granuloma Showing False-Positive Findings on FDG-PET

    OpenAIRE

    Kohei Takahara; Hiroaki Kakinoki; Saya Ikoma; Kazuma Udo; Shohei Tobu; Yuji Satoh; Yuji Tokuda; Mitsuru Noguchi; Shigehisa Aoki; Jiro Uozumi

    2013-01-01

    We report a case of a 33-year-old male with a mixed germ-cell testicular tumor. Postoperative follow-up FDG-PET revealed concentration of FDG in the left inguinal area which is not tumor metastasis or local recurrence but suture reactivity granuloma. In this paper, we reviewed suture granulomas associated with false-positive findings on FDG-PET after surgery. If FDG-PET will be used more frequently in the future, it will be necessary to refrain from using silk thread in order to prevent any u...

  12. Flexor tendon repair: a comparative study between a knotless barbed suture repair and a traditional four-strand monofilament suture repair.

    LENUS (Irish Health Repository)

    Joyce, C W

    2014-01-01

    We compared the tensile strength of a novel knotless barbed suture method with a traditional four-strand Adelaide technique for flexor tendon repairs. Forty fresh porcine flexor tendons were transected and randomly assigned to one of the repair groups before repair. Biomechanical testing demonstrated that the tensile strengths between both tendon groups were very similar. However, less force was required to create a 2 mm gap in the four-strand repair method compared with the knotless barbed technique. There was a significant reduction in the cross-sectional area in the barbed suture group after repair compared with the Adelaide group. This would create better gliding within the pulley system in vivo and could decrease gapping and tendon rupture.

  13. Storage stability of bevacizumab in polycarbonate and polypropylene syringes.

    Science.gov (United States)

    Khalili, H; Sharma, G; Froome, A; Khaw, P T; Brocchini, S

    2015-06-01

    PurposeTo compare and examine the storage stability of compounded bevacizumab in polycarbonate (PC) and polypropylene (PP) syringes over a 6-month period. PC syringes have been used in a recent clinical study and bevacizumab stability has not been reported for this type of syringe.MethodsRepackaged bevacizumab was obtained from Moorfields Pharmaceuticals in PC and PP syringes. Bevacizumab from the stored syringes was analysed at monthly time points for a 6-month period and compared with bevacizumab from a freshly opened vial at each time point. SDS-PAGE electrophoresis and size-exclusion chromatography (SEC) was used to observe aggregation and degradation. Dynamic light scattering (DLS) provided information about the hydrodynamic size and particle size distribution of bevacizumab in solution. VEGF binding and the active concentration of bevacizumab was determined by surface plasmon resonance (SPR) using Biacore.ResultsSDS-PAGE and SEC analysis did not show any changes in the presence of higher molecular weight species (HMWS) or degradation products in PC and PP syringes from T0 to T6 compared with bevacizumab sampled from a freshly opened vial. The hydrodynamic diameter of bevacizumab in the PC syringe after 6 months of storage was not significantly different to bevacizumab taken from a freshly opened vial. Using SPR, the VEGF binding activity of bevacizumab in the PC syringe was comparable to bevacizumab taken from a freshly opened vial.ConclusionNo significant difference over a 6-month period was observed in the quality of bevacizumab repackaged into prefilled polycarbonate and polypropylene syringes when compared with bevacizumab that is supplied from the vial. PMID:25853399

  14. INVESTIGATION OF THE MORPHOLOGICAL AND THERMAL PROPERTIES OF WASTE NEWSPRINT/ RECYCLED POLYPROPYLENE/ NANOCLAY COMPOSITE

    OpenAIRE

    Mohammad Amin Danesh,; Hassan Ziaei Tabari,; Reza Hosseinpourpia; , Noradin Nazarnezhad,; Morteza Shams

    2012-01-01

    The main objective of this research was to study the potential of waste polypropylene and waste newsprint fiber for making wood-plastic nanocomposites. We used 30 wt.% waste newsprint fiber and 10 wt.% compatilizer in this study. Nanoclay was used at two levels: 2.5 and 5% by wt. Materials were mixed with either recycled or virgin polypropylene. The effects of nanoclay (NC) on the mechanical and thermal properties were also studied. The improvements in tensile properties of the blended compos...

  15. Electrochemical Impedance Study of Zinc Yellow Polypropylene-Coated Aluminum Alloy

    OpenAIRE

    Feng Lu; Ming Liu; Jian-ping Cai; Zhi-hua Sun; Ni Zhang

    2010-01-01

    Performance of zinc yellow polypropylene-coated aluminum alloy 7B04 during accelerated degradation test is studied using electrochemical impedance spectroscopy (EIS). It has been found that the zinc yellow polypropylene paint has few flaw and acts as a pure capacitance before accelerated test. After 336-hour exposure to the test, the impedance spectroscopy shows two time constants, and water has reached to the aluminum alloy/paint interface and forms corrosive microcell. For the scratched sam...

  16. Development of a Halogen Free Flame Retardant Masterbatch for Polypropylene Fibers

    Directory of Open Access Journals (Sweden)

    François Rault

    2015-02-01

    Full Text Available The efficiency of new phosphinates, in combination with melamine cyanurate, was studied using different polypropylene textile structures. The influence of different ratios up to a total amount of 6 wt% in the polypropylene fiber was investigated using the limiting oxygen index (LOI and cone calorimeter method for research purposes, while the performances were correlated to the standards FMVSS 302 (Federal Motor Vehicle Safety Standards and DIN 4102-l (Deutsches Institut für Normung used more specifically for automotive and building sector.

  17. LIGNIN-STIMULATED PROTECTION OF POLYPROPYLENE FILMS AND DNA IN CELLS OF MICE AGAINST OXIDATION DAMAGE

    OpenAIRE

    Božena Košíková; Juraj Lábaj

    2009-01-01

    The blending of polypropylene with lignin derived from chemical wood pulp manufacture makes it possible to prepare optically transparent films (thickness 50-60?m) with acceptable mechanical properties in the absence of a commercial stabilizer. The lignin preparation in the concentration 1-2 wt% possessed the ability to act as a processing stabilizer and as an antioxidant during thermal aging of polypropylene films. A DNA-protective effect of lignin in mice testicular cells and mice periphera...

  18. Tensile strength characteristics of polypropylene composites reinforced with stone groundwood fibers from softwood

    OpenAIRE

    Joan P. López,; José A. Méndez,; Francesc X. Espinach,; Fernando Julián,; Pere Mutjé; Fabiola Vilaseca,

    2012-01-01

    The behavior of stone groundwood / polypropylene injection-molded composites was evaluated with and without coupling agent. Stone groundwood (SGW) is a fibrous material commonly prepared in a high yield process and mainly used for papermaking applications. In this work, the use of SGW fibers was explored as a reinforcing element of polypropylene (PP) composites. The surface charge density of the composite components was evaluated, as well as the fiber’s length and diameter inside the compos...

  19. Enhancing the Dyeability of Polypropylene Fibers by Melt Blending with Polyethylene Terephthalate

    OpenAIRE

    Fereshteh Mirjalili; Siamak Moradian; Farhad Ameri

    2013-01-01

    Attempts were made to modify polypropylene fibers by melt blending with polyethylene terephthalate in order to enhance the dyeability of the resultant fiber. Five blends of polypropylene/polyethylene terephthalate/compatibilizer were prepared and subsequently spun into fibers. Three disperse dyes were used to dye such modified fibers at boiling and 130°C. The dyeing performance of the blend fibers, as well as the morphological, chemical, thermal, and mechanical properties, of the correspondi...

  20. Electron beam irradiations of polypropylene syringe barrels and the resulting physical and chemical property changes

    International Nuclear Information System (INIS)

    Mechanical, thermal, chemical decomposition and electron spin resonance (ESR) methods were used to study electron beam irradiated polypropylene syringe barrels that were irradiated to a total fractionated dose of 0, 20, 40, 60, and 80 kGy (in steps of 20 kGy). Dose mapping was conducted to determine dose to and through the syringe barrel. Analysis of these data indicated that degradation of the polypropylene syringes increased with an increase in electron beam irradiation.

  1. Fibrous ionites on the base of radiation-grafted polypropylene fibers

    International Nuclear Information System (INIS)

    The methods of radiation grafting of acrylic acid and polypropylene-divinylbenzene copolymer on polypropylene fibers using the research installation RKhM-?-20 are considered. The pilot production of grafted fibers on the installation UGU-420 and fibrous ionites on their base FIBAN K-1, FIBAN K-4 and FIBAN A-1 are described. The mechanical and sorptive properties of the ionites as well as the areas of their application are under consideration

  2. Study of deliberate radiation-induced physical and chemical changes in polypropylene fibers

    International Nuclear Information System (INIS)

    Radiation grafting was studied of polypropylene surfaces. Radiation modification of selected samples took place simultaneously in a 10-40% solution of acrylic acid. Radiation doses were within the range of 1.75 to 7 kGy. In modified samples, increased wetting and Na ion sorption was monitored in dependence on time. The obtained experimental results proved the positive change of polypropylene fiber properties. (author)

  3. Surface grafting of polypropylene powder by UV-irradiation and ?-irradiation

    International Nuclear Information System (INIS)

    The pre-peroxidized and original polypropylene powders were grafted with monomers, including MAH, AA, EA and A, by using the methods of UV-irradiation solid phase or solution phase grafting, ?-irradiation solid phase grafting, and ?-preirradiation solution grafting. The grafted PP was characterized by means of FT-IR, ESCA and chemical titration qualitatively and quantitatively. The results showed that all monomers had grafted onto the polypropylene surface in some extent

  4. Comparison of the effects of two different types of suture material and two different suturing techniques on late postoperative stenosis in rabbit trachea

    Directory of Open Access Journals (Sweden)

    Mehmet B?LG?N

    2002-12-01

    Full Text Available Purpose: The authors aimed at determining the most suitable surgical technique and suture material in order to increase the quality of life and to decrease the surgical granulation tissue that impairs pulmonary functions by postoperative tracheal stenosis .Material and Method: This experimental study was carried out on 24 New Zeland rabbits of both sexes. Effects of two different suture materials and two different surgical techniques on late recovery period were compared in the developing rabbit trachea .Results: Average tracheal area were calculated as 19.69±2.18 mm2 in the 1st group, 15.33±2.69 mm2 in the 2nd group, 16.95±2.93 mm2 in the 3rd group and 9.01±2.64 mm2 in the 4th group. A statistically significant difference was found (p<0.05. The proportion of the tracheal area measured at control surgery to the optimal tracheal area was found as follows: 0.78 in the 1st group, 0.61 in the 2nd group, 0.69 in the 3rd group, and 0.35 in the 4th group. A statistically significant difference was found between the groups with respect to tracheal area proportions (p<0.05.Conclusion: Our results suggest that absorbable sutures that are stitched intermittently are superior to other methods or materials for the tracheobronchial reconstruction operations carried out in the childhood period.

  5. Application to refrigerator plastics by mechanical recycling from polypropylene in waste-appliances

    International Nuclear Information System (INIS)

    Highlights: ? Polypropylene is mechanically recycled from waste-appliances. ? Recycled polypropylene (RPP) is impact enhanced polypropylene with ethylene-propylene rubber (EPR). ? Performance evaluation shows that RPP is applicable to refrigerator plastics. -- Abstract: For the application to refrigerator plastics by mechanical recycling from polypropylene (PP) in waste-appliances, it needs to identify the degradation and heterogeneity of recycled polypropylene (RPP). It is applicable the thermal analysis such as differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA), spectroscopic analysis such as Fourier Transform Infrared (FTIR) and morphological analysis such as scanning electronic microscope (SEM). The analysis results show that RPP from waste-appliances is the polyethylene (PE) and polypropylene (PP) copolymer enhanced impact property (Impact-PP) and it is possible to apply refrigerator plastics with good impact property at low temperature. Finally, the performance evaluation of RPP is estimated by Gel Permeation Chromatography (GPC) analysis and is performed by the various mechanical and physical testing methods. It shows that RPP has relatively high molecular weight and balanced properties with strength and toughness. It is expected that RPP by the mechanical recycling from waste-appliances will have about 50% cost-merit.

  6. Analysis of Flexural Strength for Steel, Glass and Polypropylene Fiber Reinforced Concrete

    Directory of Open Access Journals (Sweden)

    Chapala. Venkata x Venkata Ramana

    2012-12-01

    Full Text Available This analysis study is done by using different types of fibres such as steel, glass and polypropylene with aspect ratio varying from 20 to 120 for steel, 600 to 860 for glass and 30 to 100 for polypropylene fibres.The total fibre percentages of 0 to 2?0for steel, 0 to 2?0for glass and 0 to 2.5?0for polypropylene with variation of 0.25?he design mix varying from M20 to M60 with water cement ratio 0.3 to 0.55 for steel, 0.16 to 0.55 for glass and 0.46 for polypropylene.After being cured under the standard conditions for age of 28 days the specimens of each mixture were tested to determine the corresponding flexural strength. The parameters such as grade of concrete, aspect ratio, volume fraction and tensile strength of fibre for steel, glass and polypropylene fibres respectively, while the flexural strength of the concrete were chosen as output variable. The results obtained from the model and the experiments were compared by using regression analysis, and it was check in artificial neural networks. Finally form an empirical relation between flexural strength tograde of concrete, aspect ratio, volume fraction and tensile strength of fibre for steel, glass and polypropylene fibres.

  7. Effect of compatibilization and reprocessing on the isothermal crystallization kinetics of polypropylene/wood flour composites

    Directory of Open Access Journals (Sweden)

    Arieny Rodrigues

    2013-01-01

    Full Text Available Numerous studies have focused on polymer mixtures aimed at the potential applications of these materials. This work analyzed the effect of polymer reprocessing and the type and concentration of compatibilizer on the isothermal crystallization kinetics of polypropylene/wood flour composites. The composites, which were polypropylene grafted with acrylic acid (PP-g-AA and maleic anhydride (PP-g-MA, were processed in a twin screw extruder with and without compatibilizer. Reprocessed polypropylene reached complete crystallization in less time than the composites with virgin polypropylene. The addition of wood flour to the composites did not change the kinetics significantly compared to that of the pure polymers, but the compatibilizers did, particularly PP-g-AA. The nucleation exponent (n and crystallization rate (K were calculated from Avrami plots. The values of n ranged from 2 to 3, indicating instantaneous to sporadic nucleation. The crystallization half-time of reprocessed polypropylene was shorter than that of virgin polypropylene and of the compositions containing PP-g-AA compatibilizer. The activation energy of crystallization and the equilibrium melting temperature were calculated, respectively, from Arrhenius and Hoffman-Weeks plots. Both of these parameters showed lower values in the composites, particularly in the ones containing compatibilizers.

  8. Effect of compatibilization and reprocessing on the isothermal crystallization kinetics of polypropylene/wood flour composites

    Scientific Electronic Library Online (English)

    Arieny, Rodrigues; Benjamim de M., Carvalho; Luís A., Pinheiro; Rosário E. S., Bretãs; Sebastião V., Canevarolo; Juliano, Marini.

    Full Text Available Numerous studies have focused on polymer mixtures aimed at the potential applications of these materials. This work analyzed the effect of polymer reprocessing and the type and concentration of compatibilizer on the isothermal crystallization kinetics of polypropylene/wood flour composites. The comp [...] osites, which were polypropylene grafted with acrylic acid (PP-g-AA) and maleic anhydride (PP-g-MA), were processed in a twin screw extruder with and without compatibilizer. Reprocessed polypropylene reached complete crystallization in less time than the composites with virgin polypropylene. The addition of wood flour to the composites did not change the kinetics significantly compared to that of the pure polymers, but the compatibilizers did, particularly PP-g-AA. The nucleation exponent (n) and crystallization rate (K) were calculated from Avrami plots. The values of n ranged from 2 to 3, indicating instantaneous to sporadic nucleation. The crystallization half-time of reprocessed polypropylene was shorter than that of virgin polypropylene and of the compositions containing PP-g-AA compatibilizer. The activation energy of crystallization and the equilibrium melting temperature were calculated, respectively, from Arrhenius and Hoffman-Weeks plots. Both of these parameters showed lower values in the composites, particularly in the ones containing compatibilizers.

  9. Rheo-Optics and X-Ray Scattering Study of Elastomeric Polypropylene

    Energy Technology Data Exchange (ETDEWEB)

    Pople, John A

    2001-10-16

    Elastomeric polypropylenes (ePP) have been known since the early history of polypropylene. Elastomeric polypropylenes were first synthesized by Natta using heterogeneous Ziegler-type catalysts; he attributed the elastomeric behavior to their low crystallinity and stereoisomer blocks consisting of alternating isotactic crystalline and atactic amorphous segments. Subsequent to Natta's work, there have been a number of reports of the production of related materials produced with different catalysts, with notable advances by Collette, Chien, and Collins. Recently, we reported that metallocene catalysts derived from 2-arylindene ligands produce elastomeric polypropylenes which can be separated into fractions differing in tacticity and crystallinity. Studies of the elastomeric polypropylenes using rheological and optical-polarimetry methods reveal evidence of a physical network in contrast to the blend of atactic and isotactic fractions. Dynamic infrared (IR) polarimetry studies provide evidence of cocrystallization of solvent fractions of the materials subjected to step-shear flows. In the current study, we examine the tensile flow properties of elastomeric polypropylene and its solvent fractions derived from 2-arylindene metallocenes catalysts. The origin of tensile set is studied by simultaneously measuring the tensile stress and optical birefringence. The birefringence follows the flow-induced anisotropy arising from amorphous chain orientation and oriented crystallites. Wide Angle and Small Angle X-ray Scattering (WAXS and SAXS, respectively) were performed to investigate the crystallite orientation as well as strain-induced crystallinity.

  10. Photo-oxidative degradation of TiO2/polypropylene films

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • Photo-oxidative degradation of polypropylene is accelerated by TiO2 incorporation. • Weight loss, FTIR, SEM and GPC shown high degree of degradation of polypropylene. • A mechanism of the photo-degradation of polypropylene by TiO2 is proposed. - Abstract: Photo-oxidative degradation of polypropylene films with TiO2 nanoparticles incorporated was studied in a chamber of weathering with Xenon lamps as irradiation source. TiO2 powder with crystalline structure of anatase was synthesized by thermal treatments at 400 and 500 °C starting from a precursor material obtained by sol–gel method. Composites of TiO2/polypropylene were prepared with 0.1, 0.5 and 1.0 wt% of TiO2. The mixture of components was performed using a twin screw extruder, the resulting material was pelletized by mechanical fragmenting and then hot-pressed in order to form polypropylene films with TiO2 dispersed homogeneously. Photo-oxidative degradation process was followed by visual inspection, weight loss of films, scanning electron microscopy (SEM), infrared spectroscopy with Fourier transformed (FTIR), and gel permeation chromatography (GPC)

  11. Thermal and mechanical properties of polypropylene/titanium dioxide nanocomposite fibers

    International Nuclear Information System (INIS)

    Highlights: ? Wet synthesis method was used for the synthesis of TiO2 nano particles. ? Mechanical properties of polypropylene fibers were increased by the addition of TiO2 nanoparticles. ? Thermal stability of polypropylene fiber was improved significantly by the addition of TiO2 nano particles. ? TiO2 nanoparticles dispersed well in polypropylene fibers. -- Abstract: Titanium dioxide nanoparticles were prepared by wet synthesis method and characterized by transmission electron microscopy and X-ray diffraction studies. The nanotitanium dioxide then used to prepare polypropylene/titanium dioxide composites by melt mixing method. It was then made into fibers by melt spinning and subsequent drawing. Mechanical properties of the fibers were studied using Favimat tensile testing machine with a load cell of 1200 cN capacity. Thermal behavior of the fibers was studied using differential scanning calorimetry and thermogravimetric analysis. Scanning electron microscope studies were used to investigate the titanium dioxide surface morphology and crosssection of the fiber. Mechanical properties of the polypropylene fiber was improved by the addition of titanium dioxide nanoparticles. Incorporation of nanoparticles improves the thermal stability of polypropylene. Differential scanning calorimetric studies revealed an improvement in crystallinity was observed by the addition of titanium dioxide nanoparticles.

  12. hermal Stability of Clay's Galleries in Polypropylene - Clay (montmorillonite Nanocomposites using Polypropylene-g-Maleic Anhydride as Compatibilizer

    Directory of Open Access Journals (Sweden)

    Pandu Lanang Kinasih

    2009-04-01

    Full Text Available Superior properties of food packaging can be achieved using nanocomposite technology. However, fabrication of this materials are complex and expensive. Long term objectives of this research is the synthesis of low cost polypropylene clay nanocomposites (PPCN via a short-cut method known as ‘cascade engineering'. Cascade engineering principle in PPCN fabrication is performed by using compatibilizer (to enable the mixing of PP and clay masterbatch, and PPCN in one pot process using melt mixer. This paper present the experimental results using small-angle x-ray diffraction (XRD on the thermal stability of the PPCN. Results from the XRD analysis showed that the clay was intercalated, however no significant changes were observed as a result of variation in mixing time. XRD patterns of the annealed PPCN showed reduction of MMT's gallery (deintercalation These phenomenon was probably caused by insufficient bonding and lack of compatibility between PP-g-MA and MMT.

  13. Surgical-site infection after abdominal wall closure with triclosan-impregnated polydioxanone sutures: results of a randomized clinical pathway facilitated trial (NCT00998907).

    OpenAIRE

    Justinger, Christoph; Slotta, Jan Erik; Ningel, Sebastian; Gra?ber, Stefan; Kollmar, Otto; Schilling, Martin Karl

    2013-01-01

    BACKGROUND: Wound infections after abdominal surgery are still frequent types of nosocomial infections. Suture materials might serve as a vehicle for mechanical transport of bacteria into the surgical wound. To prevent the contamination of suture material in surgical wounds, triclosan-coated suture materials with antibacterial activity was developed. We here report a prospective randomized pathway controlled trial investigating the effect of triclosan impregnation of polydioxanone sutures use...

  14. Comparação entre o uso de fio inabsorvível (polipropileno) e fio absorvível (poliglactina 910) na fixação de prótese de polipropileno em correção de defeitos músculo-aponeurótico da parede abdominal: estudo experimental em ratos Comparison between fixation of polypropylene mesh with polypropylene suture and polyglactin 910 suture for treatment of muscle-aponeurotic defects of abdominal wall: experimental study in rats

    OpenAIRE

    Álvaro Gianlupi; Manoel Roberto Maciel Trindade

    2004-01-01

    OBJETIVO: Comparar a fixação da tela de prolipropileno na correção de defeitos músculo-aponeuróticos da parede abdominal com fio absorvível (poliglactina 910) e fio inabsorvível (polipropileno). MÉTODOS: Oitenta e um ratos machos da linhagem Wistar foram submetidos a ressecção longitudinal de um segmento músculo-aponeurótico e peritoneal (3x2 cm) da parede abdominal, seguida por reforço com tela de polipropileno, em forma de ponte sobre a aponeurose. Foram distribuídos em dois grupos de acord...

  15. Estudio comparativo de microsutura vascular en ratas: punto simple y punto de colchonero horizontal / Comparative study about vascular microsurgery on rats: classic interrupted suture versus horizontal mattress suture

    Scientific Electronic Library Online (English)

    C., Casado Sánchez; F., Fidalgo Rodríguez; L., Rioja Torrejón.

    2009-09-01

    Full Text Available La Microcirugía es la técnica empleada para la realización de la microanastomosis vascular. El objetivo del presente estudio es comparar dos tipos de técnicas de microsutura: los puntos simples clásicos, de empleo habitual en la microcirugía vascular, y los puntos de colchonero horizontales, no eval [...] uados habitualmente para este tipo de cirugía. Fueron intervenidas 20 ratas albinas de la cepa Wistar (peso medio de 250 - 300 gr.) bajo anestesia general; realizamos sección transversal en la arteria femoral, procediendo a su reparación microquirúrgica inmediata. Se establecieron 2 grupos de animales: en el grupo A (n=10), la microsutura se hizo mediante 6 puntos sueltos simples, y en el grupo B (n=10), empleando 3 puntos de colchonero horizontal. Comprobamos la patencia en el desclampado inmediato y tras una hora del desclampado (para ambas técnicas fue positiva en el 100% de los casos), y la hemorragia en ambos tiempos (se registró un único caso de sangrado en el postoperatorio inmediato en el grupo B, que requirió la revisión de la microsutura). El tiempo medio de ejecución de la sutura en el grupo B, 15 minutos aproximadamente, fue más corto que en el grupo A, 21 minutos aproximadamente, diferencia estadísticamente significativa (p Abstract in english Microsurgery is the procedure of choice for vascular microanastamoses. The objective of this study was to compare two types of suture techniques: classic interrupted suture anastomoses, commonly used for vascular anastamoses in microsurgery, and another technique using horizontal mattress sutures, r [...] arely evaluated in this type of surgery. Twenty albino Wistar rats were operated (average weight: 250 - 300 gr.) under general anaesthesia. A transverse section of the femoral artery was performed and immediately followed by an anastamoses. The animals were placed into two groups of ten. The classic 6 interrupted suture anastomoses technique was performed in group A (n = 10) and another technique using 3 horizontal mattress sutures was performed in group B (n = 10). The patency was checked immediately following anastomoses and at the end of the first hour postanastomoses (for both techniques were always 100% in both times), and so was checked the presence of bleeding (only one case in group B was reported immediately following the anastomoses). The mean anastomoses time for the group B, 15 minutes approximately, was shorter than that for the group A, 21 minutes approximately, and the difference was statistically significant (p

  16. Electromagnetic images of the deep structure of the Trans-European Suture Zone beneath Polish Pomerania.

    Czech Academy of Sciences Publication Activity Database

    Ernst, T.; Brasse, H.; ?erv, Václav; Hoffmann, N.; Jankowski, J.; Jó?wiak, W.; Kreutzmann, A.; Neska, A.; Palshin, N.; Pedersen, L. B.; Smirnov, M.; Sokolova, E.; Varentsov, I. M.

    2008-01-01

    Ro?. 35, ?. 15 (2008), L15307/1-L15307/5. ISSN 0094-8276 R&D Projects: GA ?R GA205/04/0740 Institutional research plan: CEZ:AV0Z30120515 Keywords : magnetotelluric method * Trans-European Suture Zone * 2D modelling Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 2.959, year: 2008

  17. Cyanoacrylate-sealed Donati suture for wound closure after cardiac surgery in obese patients.

    Science.gov (United States)

    Grauhan, Onnen; Navasardyan, Artashes; Hofmann, Michael; Müller, Peter; Hummel, Manfred; Hetzer, Roland

    2010-12-01

    The majority of wound infections after median sternotomy in obese patients are triggered by the breakdown of skin suture and subsequent seepage of skin flora into the deeper tissue layers. In a prospective study, 90 patients (body mass index ?30) who had cardiac surgery via median sternotomy were enrolled. In 45 patients, skin closure was performed according to the Donati technique (vertical interrupted mattress suture) and sealed with octylcyanoacrylate (group A). In 45 patients, intracutaneous running technique without sealed was performed (group B). The endpoint was wound infection within 90 days. Degree of obesity and other risk factors for wound infection were equally distributed between groups A and B (all P>0.05). In group A only two superficial infections occurred, whereas in group B there were nine wound infections including two deep infections (P=0.026). In 10 of 11 infections (both groups) coagulase-negative staphylococci were isolated. In eight of 11 wound infections the caudal third of the incision was affected. Intertrigo in inframammary skin folds was found in 20.0% (18/90) of all patients but in 63.6% (seven of 11) of cases with infection. We conclude, that cyanoacrylate-sealed Donati suture is superior to intracutaneous suture technique since it offers tension-resistant closure with immediate microbial barrier properties. PMID:20852329

  18. The resurgence of barbed suture and connecting devices for use in flexor tendon tenorrhaphy

    OpenAIRE

    Gussous, Yazeed Mazen; Zhao, Chunfeng; Amadio, Peter C.; An, Kai-nan

    2011-01-01

    Barbed sutures and connecting devices have been historically described and used in flexor tendon tenorrhaphies. With the improvement in biomaterial, we have witnessed recently the resurgence of this concept. In this article, we review the historical use of barbed devices in repairing flexor tendons and explore the available barbed surgical devices that have been described in recent years.

  19. Evaluation of four suture materials for surgical incision closure in Siberian sturgeon

    Science.gov (United States)

    Boone, S. Shaun; Hernandez, Sonia M.; Camus, Alvin C.; Peterson, Douglas C.; Jennings, Cecil A.; Shelton, James L.; Divers, Stephen J.

    2015-01-01

    The visual and microscopic tissue reactions to the absorbable monofilament Monocryl, absorbable monofilament triclosan-coated Monocryl-Plus, absorbable multifilament Vicryl, and nonabsorbable monofilament Prolene were evaluated for their use of surgical closure in Siberian Sturgeon Acipenser baerii. Postoperative assessments were conducted at 1, 2, 8, 12, and 26 and 55 weeks to visually evaluate the surgical incision for suture retention, incision healing, erythema, and swelling. Incisions were also assessed microscopically at 1, 2, and 8 weeks for necrosis, inflammation, hemorrhage, and fibroplasia. The results indicated that incisions closed with either Vicryl or Prolene suture materials were more likely to exhibit more erythema or incomplete healing compared with those closed with Monocryl or Monocryl-Plus. The surgical implantation of a transmitter in the coelomic cavity did not significantly affect the response variables among the four suture materials. Monocryl or Monocryl-Plus were equally effective and superior to other suture materials used for closing surgical incisions in Siberian Sturgeon or closely related species of sturgeon. Furthermore, Monocryl or Monocryl-Plus may decrease the risk of transmitter expulsion through the incision, as surgical wounds appear to heal faster and exhibit less erythema compared with those closed with Vicryl.

  20. Adjustment of gamma radiation doses for sterilization of Egyptian surgical sutures

    International Nuclear Information System (INIS)

    The adjustment of gamma radiation doses for sterilization of catguts under local manufacturing conditions has been performed. Average total initial counts for aerobic and anaerobic bacteria per item were relatively low, in the range of 1000 counts for aerobic and 10 counts for anaerobic bacteria. The microfiora (aerobic bacteria) of the studied sutures were isolated and identified to be: Bacillus sp.; Micrococcus varians, Micrococcus roseus, and Staphylococcus. Each purified and identified isolate was exposed to gamma radiation both in liquid media (broth) and in the preservative in which the sutures were supplied by the company. The LD values of the most resistant microorganisms in both case of liquid media and preservative, were obtained to be around 5 KGy. Deliberately contaminated sterile sutures with each isolate and with mixture of isolates were studied. The sterilizing dose was obtained to be 20KGy for most heavily contaminated items (1010 counts) irradiated both in saline and in preservative. This sterilizing dose was found to be dependent of the initial viable counts. This value was considered to be a safe value for radiosterilization of the studied sutures preserved in isopropyl alcohol, glycerin, and water (90:3.5:16)

  1. A study on radiation sterilization and radiation damage for surgical suture

    International Nuclear Information System (INIS)

    The effect of Electron Beam and ? ray sterilization for silk surgical suture was studied. The initial contamination and distribution of D10 value were measured. Physical and chemical analysis of the material, such as tensile strength, water soluble extractive matter, optical density and U V spectrum were made after irradiation. In addition, a comparsion of material degradation between E B and ? sterilization was investigated

  2. 'The Closer'-percutaneous vascular suture device: evaluation of safety and performance in neuroangiography

    International Nuclear Information System (INIS)

    Objective: To evaluate the use of the suture mediated vascular closure device concerning practicability and safety in clinical angiography practice. Material and methods: One hundred and seventeen patients (59 female, 58 male, mean age 40.9±13.4) underwent percutaneous closure of common femoral arterial puncture sites following diagnostic neuroangiography using the suture device 'the Closer' (Perclose Inc., Redwood City, CA, USA). Primary success, early problems (within 24 h) and late complications were evaluated. Complications were graded as minor and severe with or without need of surgical intervention and categorized by type. Parameters such as age, gender, sheath size and number of previous arterial punctures were evaluated with respect to complications. Results: Percutaneous closure was primary successful in 85% (100/117). The overall complication rate was 32% (28% mild n=35, 4% severe n=6, which needed surgical intervention). All but one problem occurred within the first 24 h after the suture. Additional manual compression was necessary in 32 cases (25%). There was no significant difference in age and gender between the groups with and without complications. Sheath size was significantly larger (P<0.01) and numbers of preceding angiograms were significantly higher (P<0.01) in the complications group compared with uncomplicated cases. Conclusion: The evaluated percutaneous vascular suture device is useful in clinical practice but limitations concerning patient stice but limitations concerning patient selection seem to emerge in order to avoid complications

  3. Percutaneous Retrieval of a Central Venous Catheter Sutured to the Wall of the Right Atrium

    International Nuclear Information System (INIS)

    A transjugular central venous catheter was inadvertently sutured to the wall of the right atrium in a 63-year-old female during coronary bypass surgery. Using two nitinol Goose Neck snares via a transfemoral and a transjugular approach the catheter was severed into two pieces and retrieved percutaneously

  4. Tracing the influence of the Trans-European Suture Zone into the mantle transition zone.

    Czech Academy of Sciences Publication Activity Database

    Knapmeyer-Endrun, B.; Krüger, F.; Legendre, C. P.; Geissler, W.H.; Plomerová, Jaroslava; Babuška, Vladislav; Gaždová, Renata; Jedli?ka, Petr; Kolínský, Petr; Málek, Ji?í; Novotný, Old?ich; R?žek, Bohuslav

    2013-01-01

    Ro?. 363, FEB 1 (2013), s. 73-87. ISSN 0012-821X Institutional support: RVO:67985530 ; RVO:67985891 Keywords : mantle transition zone * Trans-European Suture Zone * East European Craton Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 4.724, year: 2013

  5. The cosmetic outcome of the scar formation after cesarean section : percutaneous or intracutaneous suture?

    DEFF Research Database (Denmark)

    Lindholt, Jes Sanddal; Möller-Christensen, T

    1994-01-01

    Three methods of skin closure after cesarean section were tested and compared in a prospective trial. Eighty-nine (82.5%) appeared for follow-up investigation 4-5 months after delivery. The mean scar width was significantly narrower after phannenstiel incision compared with percutaneous nylon sutures after lower midline incision, 3.1 mm versus 11.3 mm. Intracutaneous continuous PDS-suture after lower midline incision produced scars 40% narrower than with percutaneous sutures, 6.8 versus 11.3 mm. 37.5% of the women sutured intracutaneously complained over persistent secretion after discharge from the hospital. Some of these complaints were probably due to the introduction of new materials and skin closure technique. None consulted a physician with their complaints, i.e. the complications were sub-clinical. Exclusion of the women with persistent secretions from the material led to significantly narrower scars compared with percutaneous closure, 4.5 versus 11.1. Thus, even better results can be expected as experience with the technique increases. Observer and patient satisfaction with the cosmetic outcome were measured independently on a 'Lasa-line'. Their opinions coincided; the order of acceptability was worst with percutaneous wound closure after lower midline incision, next best with intracutaneous closure after lower midline incision, and best after phannenstiel incision with intracutaneous closure.

  6. Risk/benefit evaluation of the use of triclosan in surgical suturing materials

    Directory of Open Access Journals (Sweden)

    Lippert, Hans

    2006-08-01

    Full Text Available Based on the current literature, a risk/benefit analysis of the antimicrobial impregnation of surgical sutures with triclosan is performed, focussing on efficacy and indication, risk of resistance development, toxicological characteristics, and environmental tolerance. From a toxicological point of view, there are no restrictions for triclosan-impregnated suturing materials. Environmental tolerance is also acceptable for this application area, because the amounts of triclosan involved pose no problems in terms of degradability. The use of surgical suturing material coated with triclosan is seen especially in contaminated wounds or where the risk of infection is high. In order to meet this requirement, the antimicrobial properties of triclosan are particularly emphasized.Both in vitro and in vivo, triclosan is highly effective against Staphylococcus spp., including MRSA, the pathogens most frequently involved in postoperative wound infections. Triclosan is not effective against Pseudomonas aeruginosa, Serratia marcescens and Alcaligenes spp., due to their intrinsic resistance against this agent.As long as the inducible resistance in vitro against triclosan is not clinically relevant, it does not speak against triclosan use in suturing material, especially because pure triclosan is applied only to a specific, limited area for a short time. However, because triclosan can induce in vitro the development of cross-resistances to antibiotics, the implementation of this agent must be exclusively limited to medically founded indications.

  7. Role of suture anchors in management of fractures of inferior pole of patella

    Directory of Open Access Journals (Sweden)

    Anand Ashish

    2010-01-01

    Full Text Available Background: The traditional recommendation for displaced comminuted inferior pole fractures is excision of the comminuted pole followed by reattachment of the patellar tendon with transosseous suture. To the best of our knowledge there has been no previous published study mentioning the use of suture anchors for fracture inferior pole of patella. We present a retrospective analysis of five cases of patients doing well at final follow-up of two years. Materials and Methods: Five patients treated at our institute using suture anchors for repair of comminuted inferior pole fractures of patella between January 2007 to March 2007. (range 28 years-55 years. There were three males and two females. Results: The average follow-up was 25 months (range 24 months-26 months. The patients were evaluated for range of motion, strength, patellofemoral scores and any alteration of patellar height. The outcome of the procedure was assessed with use of the patellofemoral scoring system of Noyes et al, 5 as adapted by Saltzman et al. 6 The final patellofemoral score (maximum 100 points was 94.6 (range 93-96. Conclusion: We believe it is a novel extended indication of the use of suture anchors and should be in the armament of every trauma surgeon.

  8. Growing skull fracture - rupture of coronal suture caused by vacuum extraction

    International Nuclear Information System (INIS)

    Growing skull fracture is a well known complication to calvarian fracture with underlying dural tear and brain injury in infancy and early childhood. This has been reported in three cases after forceps delivery. To our best knowledge it has never been described after disruption of a calvarian suture caused by vacuum extraction delivery. (orig.)

  9. Randomized clinical trial of self-gripping mesh versus sutured mesh for Lichtenstein hernia repair

    DEFF Research Database (Denmark)

    Jorgensen, L N; Sommer, ThorbjØrn

    2013-01-01

    BACKGROUND: Many patients develop discomfort after open repair of a groin hernia. It was hypothesized that suture fixation of the mesh is a cause of these symptoms. METHODS: This patient- and assessor-blinded randomized multicentre clinical trial compared a self-gripping mesh (Parietene Progrip(®) ) and sutured mesh for open primary repair of uncomplicated inguinal hernia by the Lichtenstein technique. Patients were assessed before surgery, on the day of operation, and at 1 and 12 months after surgery. The primary endpoint was moderate or severe symptoms after 12 months, including a combination of chronic pain, numbness and discomfort. RESULTS: The intention-to-treat population comprised 163 patients with self-gripping mesh and 171 with sutured mesh. The 12-month prevalence of moderate or severe symptoms was 17·4 and 20·2 per cent respectively (P = 0·573). There were no significant differences between the groups in postoperative complications (33·7 versus 40·4 per cent; P = 0·215), rate of recurrent hernia within 1 year (1·2 per cent in both groups) or quality of life. CONCLUSION: The avoidance of suture fixation using a self-gripping mesh was not accompanied by a reduction in chronic symptoms after inguinal hernia repair. Registration number: NCT00815698 (http://www.clinicaltrials.gov). Copyright © 2012 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

  10. [Experimental study of colonic anastomoses. Comparison of different suture methods in the rat].

    Science.gov (United States)

    Bonoldi, A P; Cabano, F; Bonacina, R; Di Giacomo, A; Zonta, A

    1989-04-15

    A comparative experimental study was conducted on three different suture techniques for end-to-end colonic anastomoses. The development of stenosis, perivisceral adhesions and resistance to endoluminal pressure were assessed. The results show that the one layer all-coat interrupted stitch anastomosis displays less resistance to endoluminal pressure during the first seven days but is followed by fewer complications. PMID:2664560

  11. Hereditary premature closure of a coronal suture in the Abraham Lincoln family.

    Science.gov (United States)

    Fishman, Ronald S

    2013-10-01

    The most easily recognized facial features of unilateral premature closure of a coronal suture in the skull are an upward arching of the superior orbital rim and a smaller face on the involved side. Photographs indicate that at least 9 individuals over 5 generations of the Abraham Lincoln family showed this anomaly. PMID:23856133

  12. All-Suture Transosseous Repair for Rotator Cuff Tear Fixation Using Medial Calcar Fixation.

    Science.gov (United States)

    Aramberri-Gutiérrez, Mikel; Martínez-Menduiña, Amaia; Valencia-Mora, María; Boyle, Simon

    2015-04-01

    We describe an all-suture transosseous repair technique used in the management of rotator cuff tears by means of an all-suture anchor secured on the intra-articular side of the humeral calcar. The technique uses an anterior cruciate ligament guide to ensure accurate positioning of the tunnels, avoiding the articular cartilage and minimizing risk to the neurovascular structures. The distal end of the guide is inserted through a rotator interval portal and passed down to the axillary pouch. The proximal end of the guide is approximated to the greater tuberosity at the cuff footprint, and a complete transosseous tunnel is created with a 2.4-mm drill. An all-suture implant is inserted through this tunnel down to the calcar, and its deployment is visualized under arthroscopy. Gentle traction is applied to the anchor, resulting in a 4-mm concertina of the suture anchor that rests opposed to the medial cortex. The major advantage of this technique is the fixation strength gained from the biomechanically superior cortical bone of the calcar. Furthermore, this method permits greater preservation of bone surface area at the level of the footprint for a larger tendon-to-bone healing surface. This technique also provides an excellent alternative in revision situations. PMID:26052495

  13. Comparison of in-out and overnight catheterization in post operative urinary retention

    International Nuclear Information System (INIS)

    To compare quality of scar after subcuticular stitches between Polypropylene (Prolene), a non-absorbable suture, with Polyglactin 910 (Vicryl), an absorbable suture after thyroid surgery. Study Design: Randomized controlled trail (RCT). Place and Duration of Study: Department of Surgery Combined Military Hospital and Military Hospital Rawalpindi from 1 Jan 2007 to 31 Dec 2007. Material and Methods: Sixty patients undergoing elective thyroid surgery were included and randomly divided into two groups using random number tables. Informed written consent was obtained from each patient. The neck wound was closed by subcuticular suturing technique and the suture material was used according to the sampling technique. The patients were followed up in OPD on tenth post operative day and twelve weeks after surgery for the quality of scar. Results: After 10 days, 1 patient in each of the Polypropylene group (3.3%) and Polyglactin 910 group (3.3%) had a bad scar (p = 1.000). After twelve weeks of surgery, 2 patients in the Polypropylene group (6.7%) and 3 patients in the Polyglactin 910 group (10.0%) had bad scars (p = 1.000). Conclusion: There is no significant difference between the frequency of bad scar formation in the Polypropylene and Polyglactin 910 group. It is thus recommended that absorbable Polyglactin 910 sutures should be used for wound closure after thyroid surgery as it does not require suture removal and thus prevents patient anxiety and discomfort and also saves ent anxiety and discomfort and also saves surgeon and staff's time. (author)

  14. New adjustable suture technique for trabeculectomy / Nova técnica de sutura ajustável para trabeculectomia

    Scientific Electronic Library Online (English)

    Vespasiano, Rebouças-Santos; Daniel, Meira-Freitas; Angelino Júlio, Cariello; Tiago dos Santos, Prata; Sergio Henrique, Teixeira.

    2013-06-01

    Full Text Available OBJETIVO: Descrever uma nova técnica de sutura ajustável para o "flap" da trabeculectomia (TREC), que permite apertar e folgar a sutura no pós-operatório. MÉTODOS: Foram realizadas trabeculectoomia em 15 olhos de porco. Todos os olhos de porco foram testados duas vezes; um teste com sutura convencio [...] nal nas duas extremidades do "flap"(grupo sutura convencional), outro teste com sutura convencional em uma das extremidades e na outra extremidade a sutura ajustável proposta por esse trabalho (grupo sutura ajustável). A ordem de qual teste seria realizado primeiro em cada olho foi definida por sorteio. A pressão intraocular foi medida de forma direta em três momentos: T1) Todas as suturas apertadas; T2) Após lise de uma sutura convencional ou de afrouxar a sutura ajustável; T3) Após apertar novamente a sutura ajustável ou no caso do teste com as duas suturas convencionais após 5 minutos da lise de uma das suturas. RESULTADOS: No primeiro momento de medida da pressão intraocular (T1) as pressões médias foram similares entre os dois grupos (p=0.97). No entanto, diferenças significativas em relação a pressão intraocular foram encontradas entre os grupos de sutura convencional e ajustável nos tempos 2 (12,6 ± 4,2 vs 16,3 ± 2,3 cmH2O, respectivamente; p=0,006) e 3 (12,2 ± 4,0 vs 26,4 ± 1.7cmH2O, respectivamente; p=0,001). Enquanto a técnica convencional permitiu somente a redução da pressão intraocular após a remoção da sutura (T2 e T3), a técnica de sutura ajustável permitiu tanto a redução (T2) quanto a elevação da pressão intraocular (T3) através do manejo da sutura. CONCLUSÃO: Esse modelo experimental demonstrou a eficácia de uma possível técnica não-invasiva para ajuste da tensão da sutura do "flap"no pós-operatório da trabeculectomia. Abstract in english PURPOSE: To describe an adjustable suture (AS) experimental model that allows for tightening, loosening and retightening of the suture tension in trabeculectomy. METHODS: Standard trabeculectomy was performed in fifteen pig eyeballs. All pig eyes were tested twice: one test with conventional suture [...] in both flap's corners (conventional suture group) and another test with a conventional suture at one corner and an adjustable suture in the other corner (AS group). The order in which each test was performed was defined by randomization. Intraocular pressure was measured at three time points: T1) when the knots were tightened; T2) when the AS was loosened or the conventional knot was removed; and T3) when the AS was retightened in the AS group or five minutes after the knot removal in the conventional suture group. RESULTS: The mean Intraocular pressure was similar between the two groups at time point 1 (p=0.97). However, significant Intraocular pressure differences were found between eyes in the conventional and adjustable suture groups at time points 2 (12.6 ± 4.2 vs 16.3 ± 2.3 cmH2O, respectively, p=0.006) and 3 (12.2 ± 4.0 vs 26.4 ± 1.7cmH2O, respectively; p=0.001). While the conventional technique allowed only Intraocular pressure reduction (following the knot removal; T2 and T3), the AS technique allowed both Intraocular pressure reduction (T2) and elevation (T3) through the management (loosening and retightening) of the suture. CONCLUSION: This experimental model provides an effective noninvasive postoperative mechanism of suture tension adjustment.

  15. Sutura elástica para tratamento de grandes feridas / Elastic sutures for the treatment of extensive wounds

    Scientific Electronic Library Online (English)

    Eduardo Luiz Nigri dos, Santos; Ricardo Araujo, Oliveira.

    2012-09-01

    Full Text Available O fechamento de grandes feridas continua sendo um importante desafio para o cirurgião plástico. O objetivo deste artigo é a divulgação da sutura elástica como uma técnica eficaz para o fechamento de grandes feridas. Foram incluídos no estudo 14 pacientes portadores de grandes lesões decorrentes de t [...] raumas diversos em membros inferiores. O fechamento completo das feridas foi obtido por procedimento dividido em duas etapas, sendo a primeira representada por aproximação das bordas opostas da ferida por meio de tiras circulares elásticas de borracha e a segunda, realizada alguns dias após, com a retirada das tiras elásticas, seguida de sutura simples com fio mononáilon. A sutura elástica demonstrou ser uma técnica segura, funcionalmente eficaz, de fácil execução e de baixo custo para fechamento de grandes feridas, evitando áreas doadoras, como nos enxertos de pele. Abstract in english The suture of extensive wounds remains a major challenge for plastic surgeons. The objective of this article is to promote use of elastic sutures as an effective procedure for the closure of extensive wounds. Fourteen patients presenting with extensive wounds caused by trauma in the lower limbs were [...] included in the study. The entire wound was sutured in each patient with a two-step procedure. In the first step, the opposite edges of the wound were approximated using rubber circular elastic bands. In the second step, carried out a few days later, the elastic bands were removed, followed by a simple suture with monofilament nylon thread. Placement of elastic sutures proved to be a safe, functionally effective, easy-to-perform, and low-cost procedure for the closure of extensive wounds without using donor areas as skin grafts.

  16. Unidirectional barbed suture versus standard monofilament for urethrovesical anastomosis during robotic assisted laparoscopic radical prostatectomy

    Scientific Electronic Library Online (English)

    Marc, Manganiello; Patrick, Kenney; David, Canes; Andrea, Sorcini; Alireza, Moinzadeh.

    2012-02-01

    Full Text Available PURPOSE: V-LocTM180 (Covidien Healthcare, Mansfield, MA) is a new unidirectional barbed suture that may reduce loss of tension during a running closure. We evaluated the use of the barbed suture for urethrovesical anastomosis (UVA) during robotic assisted laparoscopic prostatectomy (RALP). Time to c [...] ompletion of UVA, post-operative anastomotic leak rate, and urinary incontinence were compared in patients undergoing UVA with 3-0 unidirectional-barbed suture vs. 3-0 MonocrylTM (Ethicon, Somerville, NJ). MATERIALS AND METHODS: Data were prospectively collected for 70 consecutive patients undergoing RALP for prostate cancer between November 2009 and October 2010. In the first 35 patients, the UVA was performed using a modified running van Velthoven anastomosis technique using two separate 3-0 monofilament sutures. In the subsequent 35 patients, the UVA was performed using two running novel unidirectional barbed sutures. At 7-12 days postoperatively, all patients were evaluated with a cystogram to determine anastomotic integrity. Urinary incontinence was assessed at two months and five months by total daily pad usage. Clinical symptoms suggestive of bladder neck contracture were elicited. RESULTS: Age, PSA, Gleason score, prostate size, estimated blood loss, body mass index, and clinical and pathologic stage between the 2 groups were similar. Comparing the monofilament group and V-LocTM180 cohorts, average time to complete the anastomosis was similar (27.4 vs. 26.4 minutes, p = 0.73) as was the rate of urinary extravasation on cystogram (5.7 % vs. 8.6%, p = 0.65). There were no symptomatic bladder neck contractures noted at 5 months of follow-up. At 2 months, the percentage of patients using 2 or more pads per day was lower in the V-LocTM180 cohort (24% vs. 44%, p

  17. Evaluation of foaming polypropylene modified with ramified polymer

    Science.gov (United States)

    Demori, Renan; de Azeredo, Ana Paula; Liberman, Susana A.; Mauler, Raquel S.

    2015-05-01

    Polypropylene foams have great industrial interest because of balanced physical and mechanical properties, recyclability as well as low material cost. During the foaming process, the elongational forces applied to produce the expanded polymer are strong enough to rupture cell walls. As a result, final foam has a high amount of coalesced as well as opened cells which decreases mechanical and also physical properties. To increase melt strength and also avoid the coalescence effect, one of the current solution is blend PP with ramified polymers as well as branched polypropylene (LCBPP) or ethylene-octene copolymer (POE). In this research to provide extensional properties and achieve uniform cellular structures of expanded PP, 20 phr of LCBPP or POE was added into PP matrix. The blend of PP with ramified polymers was prepared by twin-screw extrusion. Injection molding process was used to produce PP foams using azodicarbonamide (ACA) as chemical blowing agent. The morphological results of the expanded PP displayed a non-uniform geometrical cell, apparent density of 0.48 g/cm3 and cell density of 13.9.104 cell/cm3. Otherwise, the expanded PP blended with LCBPP or POE displayed a homogeneous cell structure and increased the amount of smaller cells (50-100 ?m of size). The apparent density slightly increased with addition of LCBPP or POE, 0.64 and 0.57 g/cm3, respectively. Thus, the cell density reduced to 65% in PP/LCBPP 100/20 and 75% in the sample PP/POE 100/20 compared to expanded PP. The thermo-mechanical properties (DMTA) of PP showed specific stiffness of 159 MPa.cm-3.g-1, while the sample PP/LCBPP 100/20 increased the stiffness values of 10%. Otherwise, the expanded PP/POE 100/20 decreased the specific stiffness values at -30%, in relation to expanded PP. In summary, blending PP with ramified polymers showed increasing of the homogenous cellular structure as well as the amount of smaller cells in the expanded material.

  18. Inhibition of secondary cartilage of the intermaxillary suture in Sprague-Dawley rats following the enucleation of maxillary molars

    International Nuclear Information System (INIS)

    A single craniofacial suture can undergo several morphologic transformations during its development. From 3 to 7 weeks of age, the intermaxillary suture of the rat is synchondrotic in character, featuring secondary cartilage; at later times, this suture is syndesmotic in character, featuring a fibrous tissue interface. Since intermittent mechanical stimulation has been reported to initiate secondary cartilage formation, a study was done to determine if the functioning dentition were responsible for secondary cartilage formation in the intermaxillary suture of the rat. Twenty-two female Sprague-Dawley rats were used. At 3 weeks of age, prior to eruption, the maxillary molars were enucleated from nine animals. Body weights were recorded weekly. Animals were sacrificed weekly from 4 to 7 weeks of age. One hour prior to sacrifice, each rat was injected with [35S]sulfate at a dosage of 2 microCi/g body weight. The tissues were evaluated by light microscopy and autoradiography. In the experimental group, the midpalatal suture did not undergo the normal synchondrotic transformation. Instead, this suture remained fibrous with negligible metachromatic staining. In the control animals, the peak period of [35S]sulfate incorporation was 4 weeks of age and was five times greater than in the experimental group. The primary stimulus for the initiation of secondary cartilage formation in the midpalatal suture of the rat was molar function. Also, functioning molawas molar function. Also, functioning molars were found to be important in the maintenance of the palatal bone

  19. Radiological assessment of skull base changes in children with syndromic craniosynostosis: role of ''minor'' sutures

    Energy Technology Data Exchange (ETDEWEB)

    Calandrelli, Rosalinda; D' Apolito, Gabriella; Gaudino, Simona; Stefanetti, Mariangela; Colosimo, Cesare [Universita Cattolica Sacro Cuore, Institute of Radiology, Rome (Italy); Massimi, Luca; Di Rocco, Concezio [Universita Cattolica Sacro Cuore, Institute of Neurosurgery, Rome (Italy)

    2014-10-15

    This study aims to identify the premature synostosis of ''major'' and ''minor'' sutures of the four ''sutural arches'' of the skull and to perform a morphometric analysis in children with syndromic craniosynostosis in order to evaluate changes in the skull base linked with premature suture synostosis. We reviewed multiplanar high-resolution CT images, implemented with 3D reconstructions, from 18 patients with complex syndromic craniosynostosis and compared them with 18 age-matched healthy subjects. We assessed the calvarial sutures and their extension to the skull base, and then we correlated specific types of synostosis with the size, shape and symmetry of the cranial fossae. We found a marked asymmetry of the skull base growth in all patients. The synostotic involvement around the coronal ring caused a reduction in the growth of the anterior and middle fossae. The size of the posterior cranial fossa was related not only to ''major'' but also to ''minor'' suture synostosis of the lambdoid and parieto-squamosal arches. Changes in the skull base and craniofacial axis symmetry are due to structural and functional relationships between ''major'' and ''minor'' skull sutures, suggesting a structural and functional relationship between the neurocranium and basicranium. The early recognition of prematurely closed skull base sutures may help clinicians and neurosurgeons to establish correct therapeutic approaches. (orig.)

  20. The red-eared slider turtle carapace under fatigue loading: The effect of rib-suture arrangement.

    Science.gov (United States)

    Achrai, Ben; Daniel Wagner, H

    2015-08-01

    Biological structures consisting of strong boney elements interconnected by compliant but tough collagenous sutures are abundantly found in skulls and shells of, among others, armadillos, alligators, turtles and more. In the turtle shell, a unique arrangement of alternating rigid (rib) and flexible (suture) elements gives rise to superior mechanical performance when subjected to low and high strain-rate loadings. However, the resistance to repeated load cycling - fatigue - of the turtle shell has yet to be examined. Such repeated loading could approximately simulate the consecutive high-stress bending loads exerted during (a predator) biting or clawing. In the present study flexural high-stress cyclic loads were applied to rib and suture specimens, taken from the top dorsal part of the red-eared slider turtle shell, termed carapace. Subsequently, to obtain a more complete and integrated fatigue behavior of the carapace, specimens containing a complex alternating rib-suture-rib-suture-rib configuration were tested as well. Although the sutures were found to be the least resistant to repeated loads, a synergistic effect was observed for the complex specimens, displaying improved fatigue durability compared to the individual (suture or even rib) constituents. This study may assist in the design of future high-stress fatigue-resistant materials incorporating complex assemblies of rigid and flexible elements. PMID:26042699

  1. Statistical analysis of biomechanical properties of the adult sagittal suture using a bending method in a Japanese forensic sample.

    Science.gov (United States)

    Torimitsu, Suguru; Nishida, Yoshifumi; Takano, Tachio; Koizumi, Yoshinori; Hayakawa, Mutsumi; Yajima, Daisuke; Inokuchi, Go; Makino, Yohsuke; Motomura, Ayumi; Chiba, Fumiko; Iwase, Hirotaro

    2015-04-01

    This study examined the mechanical properties of the adult sagittal suture compared with surrounding parietal bones using bending tests and investigated the association between the mechanical properties of the suture and age. We used the heads of 116 Japanese cadavers (76 male cadavers and 40 female cadavers) of known age and sex. A total of 1160 cranial samples, 10 from each skull, were collected. The samples were imaged using multidetector computed tomography, and the sample thickness at the center of each sample (ST) was measured. The failure stress of each sample (FS) was measured by a bending test, and the ratio of failure stress to the square of sample thickness (FS/ST(2)) was calculated. Statistical analyses revealed that the FS and FS/ST(2) values were significantly lower at all suture sites than at all bone sites regardless of sex. There were not significant but slight positive correlations between age and FS and FS/ST(2) values at any suture site in male samples. In female samples, age had significant positive correlations with FS and FS/ST(2) values at the middle suture sites, whereas there were not significant but slight positive correlations between age and FS and FS/ST(2) values at the edges of the suture. Statistical analyses also demonstrated that FS and FS/ST(2) values were significantly greater in male samples than in female samples at the middle suture sites. These findings suggest that the bending strength of the adult sagittal suture is significantly lower than that of surrounding parietal bones. Therefore, avoiding direct impact on cranial sutures may be important for preventing skull fractures and severe complications that can cause death. The results of this study also revealed that the bending strength of the middle sagittal suture significantly increases with age in only female samples, whereas the bending strength is significantly higher in male samples than in female samples at the middle suture sites, indicating the possibility of sex difference in the bony interdigitation of the sutures during childhood. PMID:25679987

  2. Microscopic, physical and mechanical analysis of polypropylene fiber reinforced concrete

    International Nuclear Information System (INIS)

    This investigation examined the reinforcing effects and mechanisms of polypropylene fiber (PF) on the physical and mechanical properties of concrete. Scanning electron microscope (SEM) was used to observe the crystal structures and that at the aggregate-cement interfacial transition zone. Physical and mechanical tests were performed to measure the effects of PF on improving concrete's engineering properties. Results indicate that PF significantly alters the microstructure of concrete, reduces the crystallization and orientation of Ca(OH)2, and decreases micro-voids. Specifically, PF forms a network that restricts the growth of Ca(OH)2, bridges cracking, and reallocates stresses. PF has reduced the amount and size of crystalline, and the micro-cracking at the aggregate-cement interfacial transition zone. As a result, PF has effectively improved concrete's compressive strength, flexural strength, bonding strength, dynamic performance, and fatigue life, while reduced the water penetration and abrasion mass loss. Results also indicate that a PF content of 0.9 kg/m3 has the optimum concrete performance output for the materials used in this study.

  3. Anticoagulant and antimicrobial finishing of non-woven polypropylene textiles

    International Nuclear Information System (INIS)

    The aim of this work is to prepare non-woven polypropylene (PP) textile functionalized with bioactive molecules in order to improve its anticoagulation and antibacterial properties. This paper describes the optimization of the grafting process of acrylic acid (AA) on low-pressure cold-plasma pre-activated PP, the characterization of the modified substrates and the effect of these modifications on the in vitro biological response towards cells. Then, the immobilization of gentamicin (aminoglycoside antibiotic) and heparin (anticoagulation agent) has been carried out on the grafted samples by either ionic interactions or covalent linkages. Their bioactivity has been investigated and related to the nature of their interactions with the substrate. For gentamicin-immobilized AA-grafted samples, an inhibition radius and a reduction of 99% of the adhesion of Escherichia coli have been observed when gentamicin was linked by ionic interactions, allowing the release of the antibiotic. By contrast, for heparin-immobilized AA-grafted PP samples, a strong increase of the anticoagulant effect up to 35 min has been highlighted when heparin was covalently bonded on the substrate, by contact with the blood drop. (paper)

  4. Mechanical and morphological characterization of polypropylene toughened with olefinic elastomer

    Directory of Open Access Journals (Sweden)

    Cybele Lotti

    2000-04-01

    Full Text Available The effect of incorporating (C2-C8 ethylene-octene elastomer on the mechanical properties and morphology of polypropylene copolymers has been investigated employing two types of PP copolymer, with and without nucleating agent. The results were compared to the ones presented by a commercial PP heterophase (reactor impact modified PP/EPR. The addition of the elastomer increases the toughness of the blends but reduces their stiffness. PP blends in the low elastomer content region (< 20% show low values of the Izod impact strength and both, elastomer content and impact strength, are directly proportional to the area under the beta damping peak or its maximum intensity of the elastomer. The morphology is a continuous pattern of segregate elastomeric particles with average particle size in the range of 0.27 mum to 0.39 mum. The average particle size and particle size distribution plotted in log-normal distribution curves, increases slightly with the increase in the elastomer content. The reactor modified PP heterophase has a broader particle size distribution and an average particle size of 0.56 mum, at the lower limit but inside the range for good impact performance, as observed.

  5. Mechanical and Morphological Properties of Polypropylene/Polyoxymethylene Blends

    Directory of Open Access Journals (Sweden)

    Sirirat Wacharawichanant

    2013-07-01

    Full Text Available This work studies the mechanical and morphological properties of polypropylene (PP/polyoxymethylene (POM blends. The PP/POM blends were prepared by melting-blend with an internal mixer. The contents of PP were used at 10%, 20%, 30%, 70%, 80% and 90% by weight. The phase morphology of the blends was observed by scanning electron microscope (SEM due to the mechanical properties depended on the phase morphology. The results show the decrease of the impact strength, Young’s modulus and tensile strength of POM/PP blends with increasing of PP content up to 30 wt% and then increase again with a high PP content. The percent strain at break of the blends increases after adding PP in a range of 70 - 90 wt%. SEM study reveals that the POM/PP blends clearly demonstrate a two-phase matrix-particle microstructure. The results also show that the domain size of dispersed PP or POM phase increases with increasing PP or POM content. The POM domain size is smaller than the PP domain size which leads to a little change of mechanical results of PP.

  6. Effect of isotacticity on radiation stability of polypropylene

    International Nuclear Information System (INIS)

    The relationship between radiation stability and isotacticity of polypropylene(PP), such as isotactic pentad ratio, was studied in this paper. It was found that the higher isotacticity, the better radiation stability. Compared with normal PP powder which has normal isotacticity, the special PP powder with higher isotacticity, such as, isotactic pentad ratio > 98%, can keep the Melting Index change less than normal PP after UV-light-oxygen aging or ?-irradiation in air. Furthermore, the special PP powder with higher isotacticity has lower intention of crosslinking or branching after 1KGy ?-irradiation in vacuum and has lower intention of degradation after 5KGy ?-irradiation in vacuum. The special PP powder with higher isotacticity also has lower content of carbonyl after 25KGy ?-irradiation in air. These demonstrated that the special PP with higher isotacticity made from 'special catalyst' is more suitable as the material for radiation sterilization than normal PP, because there are less 'week points' in PP with higher isotacticity than that in PP with lower isotacticity. The random copolymer with 2.7% ethylene units made from the 'special catalyst' mentioned above is even more stable in irradiation sterilization than homopolypropylene with higher isotacticity; therefore, it is reasonable that a random copolypropylene with about 4%wt ethylene made from the 'special catalyst' should be the much more suitable PP material than normal PP for irradiation sterilization. (author)

  7. Benzothiazole sulfide compatibilized polypropylene/halloysite nanotubes composites

    Energy Technology Data Exchange (ETDEWEB)

    Liu Mingxian [Department of Polymer Materials and Engineering, South China University of Technology, Guangzhou 510640 (China); Guo Baochun, E-mail: psbcguo@scut.edu.cn [Department of Polymer Materials and Engineering, South China University of Technology, Guangzhou 510640 (China); Lei Yanda; Du Mingliang; Jia Demin [Department of Polymer Materials and Engineering, South China University of Technology, Guangzhou 510640 (China)

    2009-02-15

    Clay-philic benzothiazole sulfide, capable of donating electrons, is grafted onto polypropylene (PP) backbones when N-cyclohexyl-2-benzothiazole sulfonamide (CBS), a commonly used accelerator in the tire industry, is included in the processing of PP/halloysite nanotubes (HNTs) composites. CBS decomposes at elevated temperature and yields benzothiazole sulfide radicals, which react with the PP polymeric free radicals generated during the processing of the composites. On the other hand, the benzothiazole group of CBS is reactive to HNTs via electron transferring. The compatibilization between HNTs and PP is thus realized via interfacial grafting and electron transferring mechanism. The interfacial interactions in the compatibilized systems were fully characterized. Compared with the control sample, the dispersion of HNTs and the interfacial bonding are enhanced substantially in the compatibilized composites. The significantly improved mechanical properties and thermal properties of benzothiazole sulfide compatibilized PP/HNTs composites are correlated to the enhanced interfacial property. The present work demonstrates a novel interfacial design via interfacial grafting/electron transferring for the compatibilization of PP/clay composites.

  8. Pulsed and CW NMR study of drawn polypropylene fibres

    International Nuclear Information System (INIS)

    Pulsed and broad-line proton NMR was used in investigation of both the molecular motions and the relaxations in oriented partially crystalline polypropylene (PP) fibres. Proton NMR measurements were made of the spin-lattice and rotating-frame relaxation times (T1, T1r resp.), spectra unfolding into elementary components and the second moment of the spectra in the temperature range of 250-400 K for three kinds of drawn PP fibres. The fibres were made from isotactic PP marked as Tatren 430 produced by Slovnaft Bratislava. Relaxation time T1 was measured by a multiple-pulse saturation recovery method. Rotating-frame data T1r were obtained with radiofrequency field B1=1.7 mT using the spin-locking method. The results of the experiments show that the differences in nuclear relaxation behavior are closely related to the structural changes (crystallinity and orientation) caused by the drawing process at different temperatures. (Z.S.) 4 figs., 10 refs

  9. Formation and antifouling properties of amphiphilic coatings on polypropylene fibers.

    Science.gov (United States)

    Goli, Kiran K; Rojas, Orlando J; Genzer, Jan

    2012-11-12

    We describe the formation of amphiphilic polymeric assemblies via a three-step functionalization process applied to polypropylene (PP) nonwovens and to reference hydrophobic self-assembled n-octadecyltrichlorosilane (ODTS) monolayer surfaces. In the first step, denatured proteins (lysozyme or fibrinogen) are adsorbed onto the hydrophobic PP or the ODTS surfaces, followed by cross-linking with glutaraldehyde in the presence of sodium borohydride (NaBH(4)). The hydroxyl and amine functional groups of the proteins permit the attachment of initiator molecules, from which poly (2-hydroxyethyl methacrylate) (PHEMA) polymer grafts are grown directly through "grafting from" atom transfer radical polymerization. The terminal hydroxyls of HEMA's pendent groups are modified with fluorinating moieties of different chain lengths, resulting in amphiphilic brushes. A palette of analytical tools, including ellipsometry, contact angle goniometry, Fourier transform infrared spectroscopy in the attenuated total reflection mode, and X-ray photoelectron spectroscopy is employed to determine the changes in physicochemical properties of the functionalized surfaces after each modification step. Antifouling properties of the resultant amphiphilic coatings on PP are analyzed by following the adsorption of fluorescein isothiocyanate-labeled bovine serum albumin as a model fouling protein. Our results suggest that amphiphilic coatings suppress significantly adsorption of proteins as compared with PP fibers or PP surfaces coated with PHEMA brushes. The type of fluorinated chain grafted to PHEMA allows modulation of the surface composition of the topmost layer of the amphiphilic coating and its antifouling capability. PMID:23013136

  10. [Investigation of nascent polypropylene in-reactor alloy particles].

    Science.gov (United States)

    Luo, Hua-Lin; Zhang, Chun-Bo; Niu, Hui; Zhao, Ying; Dong, Jin-Yong; Wu, Jin-Guang; Wang, Du-Jin

    2013-02-01

    Heterogeneous nascent particles were observed in a pilot product of polypropylene in-reactor alloy, which was polymerized by Ziegler-Natta/Metallocene hybrid catalyst using Spheripol technology. Most of the particles in the product are translucent, and opaque particles were observed as well. The differences in morphology, composition, chain structure, thermal properties and mechanical properties between these two kinds of particles were investigated by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), polarized optical microscopy (POM), and differential scanning calorimetry (DSC) techniques. The results of FTIR, NMR and SEM indicate that different morphology of these two different particles is caused by different content of ethylene-propylene copolymers. The results of DSC and POM showed that the translucent particles has higher crystallization rate than opaque particles due to the presence of ethylene-propylene copolymers. The mechanical properties results showed that the impact resistance property of opaque particles is obviously lower than that of translucent particles, while its tensile strength and bending modulus are much higher than that of translucent particles. Based on the process of Spheripol technology, a preliminary explanation for the formation of different nascent PP in-reactor alloy particles is proposed. PMID:23697124

  11. Influence of chemical treatment of clay to obtain polypropylene nanocomposites

    International Nuclear Information System (INIS)

    Commercial clay was chemically treated to prepare a Ziegler-Natta catalyst containing MgCl2 and clay for the synthesis of polypropylene nanocomposites by in situ polymerization. The performance of this catalyst and materials obtained in propylene polymerization was compared with a reference catalyst (without clay) and with another, whose composition presents the same clay but without prior chemical treatment. Techniques like differential scanning calorimetry (DSC), X-ray diffractometry (XRD) and melt flow index (MFI) measurements were performed. There was a marked reduction in catalytic activity of clay catalysts in comparison with the reference one, and a slight reduction in melting temperature of the polymers produced from first ones. The melt flow index of polymers obtained with treated clay were notably higher than those synthesized with the untreated clay, so the treated clay caused treated the production of PP's with lower molar mass. The clays showed an increase of spacing and irregular stacking of the lamellas, especially if chemically treated. (author)

  12. Functional behaviour of polypropylene/ZnO-soluble starch nanocomposites

    International Nuclear Information System (INIS)

    ZnO-polypropylene nanocomposites (nano-PP) were prepared using nanoparticles of ZnO stabilized by soluble starch (nano-ZnO) as filler in PP by the melt mixing process. X-ray diffraction (XRD) and other spectroscopic analysis-ultraviolet-visible (UV-vis), Fourier transform infrared (FTIR) and photoluminescence-revealed the presence and characteristics of nano-ZnO in the composites. The presence of ZnO imparts whiteness, while starch increased the yellowing of polymers. The nanocomposites were analyzed for changes in optical, mechanical, electrical and rheological properties, as influenced by the increasing concentration of nano-ZnO. The mechanical properties were marginally increased and the dielectric strength of the nano-PP increased to a notable level. By monitoring the evolution of the carbonyl absorption bands from FTIR analysis, the efficacy of nano-ZnO in the reduction of photo-degradation due to UV irradiation was demonstrated. The excellent antibacterial activity exhibited by nano-ZnO impregnated PP against two human pathogenic bacteria, Staphylococcus aureus and Klebsiella pneumoniae, makes it a suitable candidate for food packaging applications

  13. Benzothiazole sulfide compatibilized polypropylene/halloysite nanotubes composites

    International Nuclear Information System (INIS)

    Clay-philic benzothiazole sulfide, capable of donating electrons, is grafted onto polypropylene (PP) backbones when N-cyclohexyl-2-benzothiazole sulfonamide (CBS), a commonly used accelerator in the tire industry, is included in the processing of PP/halloysite nanotubes (HNTs) composites. CBS decomposes at elevated temperature and yields benzothiazole sulfide radicals, which react with the PP polymeric free radicals generated during the processing of the composites. On the other hand, the benzothiazole group of CBS is reactive to HNTs via electron transferring. The compatibilization between HNTs and PP is thus realized via interfacial grafting and electron transferring mechanism. The interfacial interactions in the compatibilized systems were fully characterized. Compared with the control sample, the dispersion of HNTs and the interfacial bonding are enhanced substantially in the compatibilized composites. The significantly improved mechanical properties and thermal properties of benzothiazole sulfide compatibilized PP/HNTs composites are correlated to the enhanced interfacial property. The present work demonstrates a novel interfacial design via interfacial grafting/electron transferring for the compatibilization of PP/clay composites.

  14. Benzothiazole sulfide compatibilized polypropylene/halloysite nanotubes composites

    Science.gov (United States)

    Liu, Mingxian; Guo, Baochun; Lei, Yanda; Du, Mingliang; Jia, Demin

    2009-02-01

    Clay-philic benzothiazole sulfide, capable of donating electrons, is grafted onto polypropylene (PP) backbones when N-cyclohexyl-2-benzothiazole sulfonamide (CBS), a commonly used accelerator in the tire industry, is included in the processing of PP/halloysite nanotubes (HNTs) composites. CBS decomposes at elevated temperature and yields benzothiazole sulfide radicals, which react with the PP polymeric free radicals generated during the processing of the composites. On the other hand, the benzothiazole group of CBS is reactive to HNTs via electron transferring. The compatibilization between HNTs and PP is thus realized via interfacial grafting and electron transferring mechanism. The interfacial interactions in the compatibilized systems were fully characterized. Compared with the control sample, the dispersion of HNTs and the interfacial bonding are enhanced substantially in the compatibilized composites. The significantly improved mechanical properties and thermal properties of benzothiazole sulfide compatibilized PP/HNTs composites are correlated to the enhanced interfacial property. The present work demonstrates a novel interfacial design via interfacial grafting/electron transferring for the compatibilization of PP/clay composites.

  15. Polypropylene CD-organic light-emitting diode biosensing platform.

    Science.gov (United States)

    Vengasandra, Srikanth; Cai, Yuankun; Grewell, David; Shinar, Joseph; Shinar, Ruth

    2010-04-21

    This paper describes the development of a compact platform for simultaneous photoluminescence (PL)-based sensing of multiple bioanalytes using a lab-on-CD. The platform is based on microfluidic features generated on foamed polypropylene (PP) surfaces by ultrasonic micro-embossing, sub-micron thick organic light-emitting diode (OLED) pixels that serve as the PL excitation sources, and a compatible array of compact photodetectors (PDs). The localized heating resulting from the ultrasonic micro-embossing enables generation of flash-free micro-patterns on the foamed PP surfaces. The embossed features are designed to function as reservoirs, channels, valves, and reaction chambers, to allow, in combination with compact OLED/PD arrays, the simultaneous monitoring of glucose, lactate, ethanol, and dissolved oxygen (DO) in four separate single CD segments using a standard PC-CD player. The analytes' concentrations are determined following CD rotation for reagent mixing by measuring the DO level via the PL decay time of an oxygen-sensitive dye following an OLED excitation pulse. Glucose, lactate, and ethanol are monitored following their oxidation in sealed cells in the presence of oxygen and their specific oxidase enzyme, which results in consumption of DO. Calibration curves for each of the analytes and their concentrations in mixtures were monitored on the four separate segments of the bio-CD. The attributes and utility of the compact OLED-bio-CD-PD platform for sensitive and accurate monitoring of multiple analytes, and its potential field-deployability, are discussed. PMID:20358113

  16. Mechanical properties of polypropylene/calcium carbonate nanocomposites

    Directory of Open Access Journals (Sweden)

    Daniel Eiras

    2009-01-01

    Full Text Available The aim of this work was to study the influence of calcium carbonate nanoparticles in both tensile and impact mechanical properties of a polypropylene homopolymer. Four compositions of PP/CaCO3 nanocomposites were prepared in a co-rotational twin screw extruder machine with calcium carbonate content of 3, 5, 7 and 10 wt. (% The tests included SEM analyzes together with EDS analyzer and FTIR spectroscopy for calcium carbonate, tensile and impact tests for PP and the nanocomposites. The results showed an increase in PP elastic modulus and a little increase in yield stress. Brittle-to-ductile transition temperature was reduced and the impact resistance increased with the addition of nanoparticles. From the stress-strain curves we determined the occurrence of debonding process before yielding leading to stress softening. Debonding stress was determined from stress-strain curves corresponding to stress in 1% strain. We concluded that the tensile properties depend on the surface contact area of nanoparticles and on their dispersion. Finally we believe that the toughening was due to the formation of diffuse shear because of debonding process.

  17. Mechanical properties of polypropylene/calcium carbonate nanocomposites

    Scientific Electronic Library Online (English)

    Daniel, Eiras; Luiz Antonio, Pessan.

    Full Text Available The aim of this work was to study the influence of calcium carbonate nanoparticles in both tensile and impact mechanical properties of a polypropylene homopolymer. Four compositions of PP/CaCO3 nanocomposites were prepared in a co-rotational twin screw extruder machine with calcium carbonate content [...] of 3, 5, 7 and 10 wt. (%) The tests included SEM analyzes together with EDS analyzer and FTIR spectroscopy for calcium carbonate, tensile and impact tests for PP and the nanocomposites. The results showed an increase in PP elastic modulus and a little increase in yield stress. Brittle-to-ductile transition temperature was reduced and the impact resistance increased with the addition of nanoparticles. From the stress-strain curves we determined the occurrence of debonding process before yielding leading to stress softening. Debonding stress was determined from stress-strain curves corresponding to stress in 1% strain. We concluded that the tensile properties depend on the surface contact area of nanoparticles and on their dispersion. Finally we believe that the toughening was due to the formation of diffuse shear because of debonding process.

  18. Mapping physicochemical surface modifications of flame-treated polypropylene

    Directory of Open Access Journals (Sweden)

    S. Farris

    2014-04-01

    Full Text Available The aim of this work was to investigate how the surface morphology of polypropylene (PP is influenced by the surface activation mediated by a flame obtained using a mixture of air and propane under fuel-lean (equivalence ratio ? = 0.98 conditions. Morphological changes observed on flamed samples with smooth (S, medium (M, and high (H degree of surface roughness were attributed to the combined effect of a chemical mechanism (agglomeration and ordering of partially oxidized intermediate-molecular-weight material with a physical mechanism (flattening of the original roughness by the flame’s high temperature. After two treatments, the different behavior of the samples in terms of wettability was totally reset, which made an impressive surface energy of ~43 mJ•m–2 possible, which is typical of more hydrophilic polymers (e.g., polyethylene terephthalate – PET. In particular, the polar component was increased from 1.21, 0.08, and 0.32 mJ•m–2 (untreated samples to 10.95, 11.20, and 11.17 mJ•m–2 for the flamed samples S, M, and H, respectively, an increase attributed to the insertion of polar functional groups (hydroxyl and carbonyl on the C–C backbone, as demonstrated by the X-ray photoelectron spectroscopy results.

  19. The effect of nucleating agent on radiation stability of polypropylene

    International Nuclear Information System (INIS)

    The radiation stability of polypropylene (PP) with and without nucleating agent (NA) is compared in relation to radiation sterilization of medical devices. In both cases high-and-low-molecular weight PP, the addition of NA increased the transparency and peak crystallization temperature of the PP. On the other hand, in poly(propylene-co-06%ethylene) copolymer, the addition of NA did not improve the transparency but crystallization occurred at higher temperature. Thus, adding NA to PP and copolymer give the advantage of shorter moulding time in the production of medical devices. It is found that both PP and copolymer with NA are less stable during irradiation and during storage after irradiation than without NA, this being the case especially for the lower molecular weight PP. The higher transparency and peak crystallization temperature in the PP and CP with NA were found to be due to smaller spherulites. As the effect of irradiation on polymer, addition of NA induce reduction of radiation stability of polymer owing to the change in morphology. (Author)

  20. Glass Fiber Reinforced Polypropylene Mechanical Properties Enhancement by Adhesion Improvement

    Directory of Open Access Journals (Sweden)

    Mariana Etcheverry

    2012-06-01

    Full Text Available Glass fibers (GF are the reinforcement agent most used in polypropylene (PP based composites, as they have good balance between properties and costs. However, their final properties are mainly determined by the strength and stability of the polymer-fiber interphase. Fibers do not act as an effective reinforcing material when the adhesion is weak. Also, the adhesion between phases can be easily degraded in aggressive environmental conditions such as high temperatures and/or elevated moisture, and by the stress fields to which the material may be exposed. Many efforts have been done to improve polymer-glass fiber adhesion by compatibility enhancement. The most used techniques include modifications in glass surface, polymer matrix and/or both. However, the results obtained do not show a good costs/properties improvement relationship. The aim of this work is to perform an accurate analysis regarding methods for GF/PP adhesion improvement and to propose a new route based on PP in-situ polymerization onto fibers. This route involves the modification of fibers with an aluminum alkyl and hydroxy-?-olefin and from there to enable the growth of the PP chains using direct metallocenic copolymerization. The adhesion improvements were further proved by fragmentation test, as well as by mechanical properties measurements. The strength and toughness increases three times and the interfacial strength duplicates in PP/GF composites prepared with in-situ polymerized fibers.