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Sample records for eptfe surgical membrane

  1. [E-PTFE Membrane for the Management of Perforated Corneal Ulcer].

    Science.gov (United States)

    Pahor, D; Pahor, A

    2016-10-01

    Purpose: To present the surgical management of perforated corneal ulcer using PRECLUDE® Pericardial Membrane, composed of expanded polytetrafluoroethylene (e-PTFE; GORE-TEX®), as an alternative surgical procedure in patients at high risk of graft rejections and to evaluate side effects for a prolonged period. Patients and Methods: The study included all patients who were admitted to our department and underwent surgical repair of perforated corneal ulcer with the e-PTFE membrane between 2010 and 2015. In total, 8 patients (8 eyes) were enrolled. Medical records of all patients were retrospectively reviewed. The operation was performed under peribulbar anaesthesia. Non-absorbable, microporous, watertight 0.1 mm thick e-PTFE membrane was used to close the corneal ulcer. The membrane was cut to overlap the defect adequately and to achieve the desired tissue attachment without preparing the conjunctiva or superficial trephination of the cornea. The membrane was fixed to the healthy cornea with several non-absorbable sutures (Prolene® 10.0), in order to achieve the proper stress without wrinkling. Results: Five of 8 patients were treated for systemic immunological diseases. Sjögren's syndrome was diagnosed in 2 patients, granulomatosis with polyangiitis in one, vasculitis with a history of previous sclerokeratitis in one and systemic lupus erythematosus in one. In 2 patients, corneal perforation was observed as a complication of corneal infection and in one patient as a late complication of a severe chemical burn. Corneal perforations were successfully covered with e-PTFE membrane in all patients. E-PTFE membrane was well tolerated in all patients and the eye was always preserved. After 3 to 4 months, the membrane was removed in 7 patients. The underlying cornea was thin, firm, stable and vascularised. In one patient with Sjögren's syndrome, the e-PTFE membrane is still in place. Conclusion: Surgical management of perforated corneal ulcer using E-PTFE membrane

  2. Comparison of TEVAR resin beads, PAN fibers, and ePTFE membranes as a solid support for Aliquat-336 in immobilized liquid extraction chromatography for separation of actinides

    International Nuclear Information System (INIS)

    Joe Dauner; Steve Workman

    2012-01-01

    The following paper covers a comparison of two new systems to traditional TEVA R resin systems for the analytical separation of actinides by immobilized liquid-liquid extraction using Aliquat-336. The new systems are using expanded polytetrafluroethane (ePTFE) membrane or polyacrylonitrile (PAN) fibers as the solid support. The systems are compared in two ways. First in how much Aliquat-336 they contain with the Vs, ratio of volume of Aliquat-336 to volume of polymeric support, being 0.158, 0.483, and 0.590 for the TEVA R resin, PAN fibers, and the ePTFE systems, respectively. The second comparison is in their performance capacity of extraction of uranyl chloride anion complex. The fiber and resins systems show similar capacities, and the membrane system being an order of magnitude less than the other systems. A cost comparison demonstrates the savings advantages of using a fiber based support compared with resin and membrane support systems. (author)

  3. Grafted functional groups on expanded tetrafluoroethylene (ePTFE) support for fuel cell and water transport membranes

    Science.gov (United States)

    Fuller, Timothy J.; Jiang, Ruichun

    2017-01-24

    A method for forming a modified solid polymer includes a step of contacting a solid fluorinated polymer with a sodium sodium-naphthalenide solution to form a treated fluorinated solid polymer. The treated fluorinated solid polymer is contacted with carbon dioxide, sulfur dioxide, or sulfur trioxide to form a solid grafted fluorinated polymer. Characteristically, the grafted fluorinated polymer includes appended CO.sub.2H or SO.sub.2H or SO.sub.3H groups. The solid grafted fluorinated polymer is advantageously incorporated into a fuel cell as part of the ion-conducting membrane or a water transport membrane in a humidifier.

  4. Autogenous bone graft and ePTFE membrane in the treatment of peri-implantitis. II. Stereologic and histologic observations in cynomolgus monkeys

    DEFF Research Database (Denmark)

    Schou, Søren; Holmstrup, Palle; Skovgaard, Lene Theil

    2003-01-01

    autogenous bone graft; guided bone regeneration; histology; membrane; non-human primates; oral implants; osseointegration; pathalogy; peri-implantitis; stereology; treatment......autogenous bone graft; guided bone regeneration; histology; membrane; non-human primates; oral implants; osseointegration; pathalogy; peri-implantitis; stereology; treatment...

  5. Laparoscopic diaphragmatic hernia repair using expanded polytetrafluoroethylene (ePTFE) for delayed traumatic diaphragmatic hernia.

    Science.gov (United States)

    Jee, Yeseob

    2017-06-01

    Traumatic diaphragmatic hernia (TDH) is an uncommon surgical problem, and diagnosis is often delayed. However, the mortality from bowel necrosis can reach 80%. Therefore, suspicion is needed and surgery is required to prevent complications. A 50-year-old man was transferred due to abdominal pain and vomiting. Chest X-ray and computed tomography (CT) scan showed herniation of the stomach through the left diaphragm. The patient had fallen down 15 months ago and CT scan at that time revealed a small defect of the diaphragm without herniation. We diagnosed delayed herniation of TDH and the patient underwent laparoscopic repair using an expanded polytetrafluoroethylene (ePTFE) mesh. Recovery was uneventful and the CT scan at 3 months after the operation showed no recurrence. We reported a delayed presenting TDH and considered a laparoscopic approach to be safe and feasible during elective surgery. Moreover, use of an ePTFE mesh for repair of large diaphragmatic hernia was also feasible.

  6. Polyurethane membranes for surgical gown applications

    Science.gov (United States)

    Ukpabi, Pauline Ozoemena

    The Occupational Safety and Health Administration (OSHA) recently issued a directive requiring all employers to supply personnel protective equipment to employees who are at risk of exposure to blood or other potentially infectious body fluids. For the healthcare worker, a wide variety of surgical gowns is available commercially but there are concerns over their barrier effectiveness and/or wearer comfort. To successfully create a barrier fabric which combines resistance to fluid penetration with comfort, a complete understanding of the relationship between membrane structure and functional properties is required. In this study, we investigated the surface properties of hydrophilicity and hydrophobicity in polyurethane membranes intended for use in surgical gowns. The polyurethane membranes were grafted with side chains of varying lengths, polyethylene glycol (PEG) being used for the hydrophilic modifications and perfluoroalkyl compounds (a monofunctional acid and a difunctional amino alcohol) for the hydrophobic modifications. The hydrophilic treatment was intended to improve the comfort properties of monolithic membranes without adversely affecting their barrier properties. The hydrophobic treatment, on the other hand, was intended to improve the fluid repellency and hence barrier properties of microporous membranes without adversely affecting their comfort properties. Reflection infrared spectroscopy showed that fluorine was successfully grafted onto the polyurethane backbone during the hydrophobic modification, but was not sensitive enough to detect PEG grafting in leached polyethylene glycol-treated polyurethanes. X-ray photoelectron spectroscopy showed that the perfluoroalkylated polyurethanes contained up to 40% fluorine on their surfaces and the PEG-treated polyurethanes showed an increase in their C-O content over the unmodified polyurethane. Scanning electron microscopy not only showed that perfluoroalkylation yielded polyurethane membranes with very

  7. Implant surface preparation in the surgical treatment of experimental peri-implantitis with autogenous bone graft and ePTFE membrane in cynomolgus monkeys

    DEFF Research Database (Denmark)

    Schou, Søren; Holmstrup, Palle; Jørgensen, Torben

    2003-01-01

    peri-implantitis; treatment; implant surface preparation; nonhuman primates; histology; stereology......peri-implantitis; treatment; implant surface preparation; nonhuman primates; histology; stereology...

  8. Biomechanical comparison of expanded polytetrafluoroethylene (ePTFE) and PTFE interpositional patches and direct tendon-to-bone repair for massive rotator cuff tears in an ovine model.

    Science.gov (United States)

    McKeown, Andrew Dj; Beattie, Rebekah F; Murrell, George Ac; Lam, Patrick H

    2016-01-01

    Massive irreparable rotator cuff tears are a difficult problem. Modalities such as irrigation and debridement, partial repair, tendon transfer and grafts have been utilized with high failure rates and mixed results. Synthetic interpositional patch repairs are a novel and increasingly used approach. The present study aimed to examine the biomechanical properties of common synthetic materials for interpositional repairs in contrast to native tendon. Six ovine tendons, six polytetrafluoroethylene (PTFE) felt sections and six expanded PTFE (ePTFE) patch sections were pulled-to-failure to analyze their biomechanical and material properties. Six direct tendon-to-bone surgical method repairs, six interpositional PTFE felt patch repairs and six interpositional ePTFE patch repairs were also constructed in ovine shoulders and pulled-to-failure to examine the biomechanical properties of each repair construct. Ovine tendon had higher load-to-failure (591 N) and had greater stiffness (108 N/mm) than either PTFE felt (296 N, 28 N/mm) or ePTFE patch sections (323 N, 34 N/mm). Both PTFE felt and ePTFE repair techniques required greater load-to-failure (225 N and 177 N, respectively) than direct tendon-to-bone surgical repairs (147 N) in ovine models. Synthetic materials lacked several biomechanical properties, including strength and stiffness, compared to ovine tendon. Interpositional surgical repair models with these materials were significantly stronger than direct tendon-to-bone model repairs.

  9. Enterocutaneous fistula associated with ePTFE mesh: case report and review of the literature.

    Science.gov (United States)

    Foda, M; Carlson, M A

    2009-06-01

    A case of enterocutaneous fistula secondary to the erosion of an expanded polytetrafluoroethylene (ePTFE) prosthesis into the jejunum is described. This case is unusual secondary to the long experience with ePTFE and the lack of published cases similar to this one. The technical details of this case reveal extenuating circumstances associated with the fistula formation, and it is concluded that this particular case does not provide sufficient evidence to implicate ePTFE, by itself, as an etiologic agent for gastrointestinal fistulization. In addition, the published safety record of ePTFE in abdominal wall surgery is reviewed.

  10. Novel phosphate-grafted ePTFE copolymers for optimum in vitro mineralization

    International Nuclear Information System (INIS)

    Wentrup-Byrne, Edeline; Suzuki, Shuko; Groendahl, Lisbeth; Suwanasilp, Juthakarn Jessica

    2010-01-01

    Surface modification via graft copolymerization is an attractive method for optimizing polymers used in biomedical applications. We developed a novel method using a mixed solvent system (either water and dichloromethane (DCM) or water, methanol and DCM) consisting of two solvent phases for grafting 2-(methacryloyloxy)ethyl phosphate onto expanded polytetrafluoroethylene (ePTFE). This new method resulted in the fabrication of grafted membranes with greater grafting extents (GEs) (as evaluated from x-ray photoelectron spectroscopy (XPS)) in the organic phase than those obtained when grafting was carried out in a single phase. It also made it possible to graft in the aqueous phase, a process that is otherwise inhibited by the concomitant formation of large amounts of highly crystalline homopolymer. Thorough characterization of the grafted membranes using gravimetric, XPS and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) not only permitted evaluation of the grafting outcomes but also made it possible to analyze their dependence on monomer concentration and solvent composition. A selection of membranes was tested for their in vitro mineralization capacity using simulated body fluid. It was found that an 'ideal' mineralization outcome, i.e. a uniform coating of carbonated hydroxyapatite (cHAP) formed on the sample grafted in the aqueous phase of the water/DCM two-phase solvent system. A detailed discussion bringing together these results, as well as results from a series of earlier studies, allows conclusions regarding polymer chemistry and the topology necessary for cHAP mineralization.

  11. Engineering based assessment for a shape design of a pediatric ePTFE pulmonary conduit valve.

    Science.gov (United States)

    Tsuboko, Yusuke; Shiraishi, Yasuyuki; Yamada, Akihiro; Yambe, Tomoyuki; Miura, Hidekazu; Mura, Seitaro; Yamagishi, Masaaki

    2016-08-01

    The authors examined the hemodynamic characteristics of expanded polytetrafluoroethylene (ePTFE) pulmonary valved conduits quantitatively by our originally developed pediatric pulmonary mechanical circulatory system, in order to suggest the optimal shape design. The system consisted of pneumatically driven right atrium and ventricle model, a pulmonary valve chamber, and elastic pulmonary compliance model with peripheral vascular resistance units, a venous reservoir. We employed two different types of ePTFE valve and evaluated the relationship between the leaflets motion and hemodynamic characteristics by using a high-speed video camera. As a result, we successfully reproduced hemodynamic simulations in our pediatric pulmonary mock system. We confirmed that the presence of bulging sinuses in the pulmonary valved conduit reduced the transvalvular energy loss and increased the valve opening area during systolic period. Our engineering-based in vitro analysis could be useful for proposing a shape design optimization of sophisticated pediatric ePTFE pulmonary valve.

  12. Surgical outcomes after epiretinal membrane peeling combined with cataract surgery.

    Science.gov (United States)

    Yiu, Glenn; Marra, Kyle V; Wagley, Sushant; Krishnan, Sheela; Sandhu, Harpal; Kovacs, Kyle; Kuperwaser, Mark; Arroyo, Jorge G

    2013-09-01

    To compare functional and anatomical outcomes after idiopathic epiretinal membrane (ERM) peeling combined with phacoemulsification and intraocular lens implantation versus ERM peeling alone. A retrospective, non-randomised comparative case series study was conducted of 81 eyes from 79 patients who underwent ERM peeling at the Beth Israel Deaconess Medical Center between 2001 and 2010. Eyes that underwent combined surgery for ERM and cataracts (group 1) were compared with those that had ERM peeling alone (group 2) with respect to best-corrected visual acuity at 6 months and 1 year after surgery, postoperative central macular thickness (CMT) as measured on optical coherence tomography, and rates of complications, including elevated intraocular pressure (IOP), ERM recurrence and need for reoperation. Mean logMAR visual acuity improved significantly in both groups at 6 months (ppeeling alone with respect to visual and anatomical outcomes. Further studies are necessary to determine if there may be greater ERM recurrence or need for reoperation after combined surgery.

  13. Guided bone regeneration in rat mandibular defects using resorbable poly(trimethylene carbonate) barrier membranes

    NARCIS (Netherlands)

    van Leeuwen, A. C.; Huddleston Slater, J. J. R.; Gielkens, P. F. M.; de Jong, J. R.; Grijpma, D. W.; Bos, R. R. M.

    The present study evaluates a new synthetic degradable barrier membrane based on poly(trimethylene carbonate) (PTMC) for use in guided bone regeneration. A collagen membrane and an expanded polytetrafluoroethylene (e-PTFE) membrane served as reference materials. In 192 male Sprague-Dawley rats, a

  14. Guided bone regeneration in rat mandibular defects using resorbable poly(trimethylene carbonate) barrier membranes

    NARCIS (Netherlands)

    van Leeuwen, A.C.; Huddelston Slater, J.J.R.; Gielkens, P.F.M.; de Jong, J.R.; Grijpma, Dirk W.; Bos, R.R.M.

    2012-01-01

    The present study evaluates a new synthetic degradable barrier membrane based on poly(trimethylene carbonate) (PTMC) for use in guided bone regeneration. A collagen membrane and an expanded polytetrafluoroethylene (e-PTFE) membrane served as reference materials. In 192 male Sprague–Dawley rats, a

  15. Improved extraction of ePTFE and medical adhesive modified defibrillation leads from the coronary sinus and great cardiac vein.

    Science.gov (United States)

    Wilkoff, Bruce L; Belott, Peter H; Love, Charles J; Scheiner, Avram; Westlund, Randy; Rippy, Marian; Krishnan, Mohan; Norlander, Barry E; Steinhaus, Bruce; Emmanuel, Janson; Zeller, Peter J

    2005-03-01

    Permanent leads with shocking coils for defibrillation therapy are sometimes implanted in the coronary sinus (CS) and great cardiac vein (GCV). These shocking coils, as documented by pathologic examination of animal investigations, often become tightly encapsulated by fibrosis and can be very difficult to remove. One of three configurations of the Guidant model 7109 Perimeter coronary sinus shocking lead was implanted into the distal portion of the GCV of 24 sheep for up to 14 months. Group 1 had unmodified coils (control), group 2 had coils backfilled with medical adhesive (MA), and Group 3 had coils coated with expanded polytetrafluoroethylene (ePTFE). Eighteen leads, three from each group at 6 and 14 months were transvenously extracted from the left jugular vein. The remaining six animals were not subject to extraction. All animals were euthanized for pathological and microscopic examination. All six of the control, three of the MA, and one of the ePTFE leads required the use of an electrosurgical dissection sheath (EDS) for extraction. Five control, two MA, and none of the ePTFE leads had significant fibrotic attachments to the shocking coils. Significant trauma was observed at necropsy for those leads requiring the use of the EDS for extraction. Tissue ingrowth is a major impediment to the removal of defibrillation leads implanted in the CS and GCV of sheep. Reduction of tissue ingrowth by coating the shocking coils with ePTFE or by backfilling with MA facilitates transvenous lead removal with reduced tissue trauma.

  16. Combined Conjunctival Autograft and Overlay Amniotic Membrane Transplantation; a Novel Surgical Treatment for Pterygium

    Directory of Open Access Journals (Sweden)

    Siamak Zarei Ghanavati

    2014-01-01

    Full Text Available The authors report the long-term results of combined conjunctival autograft and overlay amniotic membrane transplantation (AMT for treatment of pterygium as a new surgical technique. Nineteen patients including 12 male and 7 female subjects with pterygium (primary, 14 cases; recurrent, 5 cases underwent combined conjunctival autograft and overlay AMT and were followed from 10 to 26 months. Mean age was 44.21±12.49 (range, 29.0-73.0 years. In one patient with grade T3 primary pterygium, the lesion recurred (5.2%, recurrence rate. No intra-and postoperative complication developed. This procedure seems a safe and effective surgical technique for pterygium treatment. Protection of the ocular surface during the early postoperative period reduces the friction-induced inflammation and might be helpful to prevent the recurrence.

  17. The Use of Extracorporeal Membrane Oxygenation in the Surgical Repair of Bronchial Rupture

    Directory of Open Access Journals (Sweden)

    Ju-Hee Park

    2016-02-01

    Full Text Available Extracorporeal membrane oxygenation (ECMO has been used successfully in critically ill patients with traumatic lung injury and offers an additional treatment modality. ECMO is mainly used as a bridge treatment to delayed surgical management; however, only a few case reports have presented the successful application of ECMO as intraoperative support during the surgical repair of traumatic bronchial injury. A 38-year-old man visited our hospital after a blunt chest trauma. His chest imaging showed hemopneumothorax in the left hemithorax and a finding suspicious for left main bronchus rupture. Bronchoscopy was performed and confirmed a tear in the left main bronchus and a congenital tracheal bronchus. We decided to provide venovenous ECMO support during surgery for bronchial repair. We successfully performed main bronchial repair in this traumatic patient with a congenital tracheal bronchus. We suggest that venovenous ECMO offers a good option for the treatment of bronchial rupture when adequate ventilation is not possible.

  18. [Successful treatment of surgically induced necrotizing sclerokeratitis (SINS) with systemic immunosuppresive agents and amniotic membrane grafting].

    Science.gov (United States)

    Cordero-Coma, M; Franco-Benito, M; García-Ruiz-de-Morales, J M; Alonso-Orcajo, N; Del Barrio-Manso, I

    2009-11-01

    We report the case of a 74-year-old female who developed a necrotizing sclerokeratitis affecting her left eye after uncomplicated cataract surgery. She had no previous history of systemic autoimmune disease. Histopathology of the lesion revealed necrotic granulomatosis with an increased number of plasma cells. Surgically induced necrotizing sclerokeratitis (SINS) is a serious entity which requires prompt and aggressive therapy to prevent its potential devastating ocular consequences. Conjunctival resection and amniotic membrane grafting may be necessary to temporarily interrupt local immunologic events in severe cases. However, associated systemic immunomodulatory therapy seems to be mandatory (Arch Soc Esp Oftalmol 2009; 84: 577-580).

  19. Surgical choroidal neovascular membrane removal in the era of anti-vascular endothelial growth factor agents

    Directory of Open Access Journals (Sweden)

    Nagpal Manish

    2009-01-01

    Full Text Available Intravitreal anti-vascular endothelial growth factor (VEGF agents have obtained acceptance as the mainstay in the management strategy of subfoveal choroidal neovascular membranes (CNVM due to varying etiologies. Few drawbacks include need for repeated intravitreal injections, with its adjunct risks, and the lack of a predefined treatment end point, which can cause doubts and uncertainty in the mind of the patient. Furthermore, it remains a significant financial burden for the patient. Herein we report our data of three patients who were reluctant for further re-injections of anti-VEGF agents and were therefore offered surgical removal of the CNVM by submacular surgery as an alternative treatment plan.

  20. Histological evaluation of different biodegradable and non-biodegradable membranes implanted subcutaneously in rats

    DEFF Research Database (Denmark)

    Zhao, S; Pinholt, E M; Madsen, J E

    2000-01-01

    Different types of biodegradable membranes have become available for guided tissue regeneration. The purpose of this study was to evaluate histologically three different biodegradable membranes (Bio-Gide, Resolut and Vicryl) and one non-biodegradable membrane (expanded polytetrafluoroethylene/e-PTFE...... that e-PTFE was well tolerated and encapsulated by a fibrous connective tissue capsule. There was capsule formation around Resolut and Vicryl and around Bio-Gide in the early phase there was a wide inflammatory zone already. e-PTFE and Vicryl were stable materials while Resolut and Bio-Gide fragmented...

  1. Cellular reactions of osteoblast-like cells to a novel nanocomposite membrane for guided bone regeneration

    International Nuclear Information System (INIS)

    Meng Yao; Liu Man; Wang Shaoan; Mo Anchun; Huang, Cui; Zuo Yi; Li Jidong

    2008-01-01

    This study investigated the bioactivity and biocompatibility of hydroxyapatite nanoparticles (n-HA)/Polyamide-66 (PA66) nanocomposite membrane and expanded-polytetrafluoroethylene (e-PTFE) membrane (as control) to MG63 osteoblast-like cells. The attachment and proliferation of the cells on the porous surface of nHA/PA66 membrane and the surface of e-PTFE membrane were evaluated by scanning electron microscope (SEM) observation and the MTT assay. The bioactivity of the cells on the surface of the two membranes was evaluated by testing cell viability and alkaline phosphatase (ALP) activities. The results suggested that the bioresponse of MG63 osteoblast-like cells on the porous surface of nHA/PA66 membrane was better than the bioresponse on the opposite surface of e-PTFE membrane. Because of a better cell attachment manner, there is a potential utilization of the guided bone regeneration (GBR) membrane to substitute nHA/PA66 membrane for e-PTFE membrane

  2. Cellular reactions of osteoblast-like cells to a novel nanocomposite membrane for guided bone regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Meng Yao [State Key Laboratory of Oral Diseases, West China Stomatology Hospital, Sichuan University, Chengdu 610041 (China); Department of Orthodontics, West China Stomatology Hospital, Sichuan University, Chengdu 610041 (China); Liu Man [State Key Laboratory of Oral Diseases, West China Stomatology Hospital, Sichuan University, Chengdu 610041 (China); Stomatology Health Care Center, Shenzhen Maternity and Child Healthcare Hospital, Shenzhen 518048 (China); Wang Shaoan [State Key Laboratory of Oral Diseases, West China Stomatology Hospital, Sichuan University, Chengdu 610041 (China); Mo Anchun [State Key Laboratory of Oral Diseases, West China Stomatology Hospital, Sichuan University, Chengdu 610041 (China)], E-mail: moanchun@163.com; Huang, Cui [State Key Laboratory of Oral Diseases, West China Stomatology Hospital, Sichuan University, Chengdu 610041 (China); Zuo Yi; Li Jidong [Research Center for Nano-biomaterials, Sichuan University, Chengdu 610041 (China)

    2008-11-15

    This study investigated the bioactivity and biocompatibility of hydroxyapatite nanoparticles (n-HA)/Polyamide-66 (PA66) nanocomposite membrane and expanded-polytetrafluoroethylene (e-PTFE) membrane (as control) to MG63 osteoblast-like cells. The attachment and proliferation of the cells on the porous surface of nHA/PA66 membrane and the surface of e-PTFE membrane were evaluated by scanning electron microscope (SEM) observation and the MTT assay. The bioactivity of the cells on the surface of the two membranes was evaluated by testing cell viability and alkaline phosphatase (ALP) activities. The results suggested that the bioresponse of MG63 osteoblast-like cells on the porous surface of nHA/PA66 membrane was better than the bioresponse on the opposite surface of e-PTFE membrane. Because of a better cell attachment manner, there is a potential utilization of the guided bone regeneration (GBR) membrane to substitute nHA/PA66 membrane for e-PTFE membra0008.

  3. Remission of secondary membranous nephropathy in a patient with Kimura disease after surgical resection

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    Sunhwa Lee

    2014-09-01

    Full Text Available Kimura disease (KD is an eosinophilic, granulomatous, benign, chronic inflammatory disease with an unknown etiology. A 33-year-old woman visited our hospital because of a palpable, left subclavian mass, a left scapulo-anterior pseudoaneurysm, and nephrotic syndrome. Her subclavian lymph node biopsy examination result was consistent with KD, and results of a renal biopsy indicated secondary membranous nephropathy. After renal histological examination confirmed nephropathy, treatment with prednisolone and cyclosporine was initiated, which was maintained for over 1 year. However, this therapy only provided a transient improvement in proteinuria. One year after commencing the treatment, both proteinuria and azotemia aggravated as the left axillary mass doubled in size. Finally, the mass was surgically excised, following which the azotemia rapidly normalized and proteinuria resolved within 1 month. This case shows that tumor resection in a patient with KD with secondary nephropathy may resolve secondary renal manifestations. Furthermore, reversible renal dysfunction may be caused by unknown secreted molecules.

  4. Culture of Iris Pigment Epithelial Cells on Expanded-Polytetrafluroethylene (ePTFE Substrates for the Treatment of Age-Related Macular Degeneration

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    S Nian

    2011-05-01

    Full Text Available Introduction: Transplantation of an intact differentiated retinal pigment epithelial (RPE cell layer may provide a means to treat Age-Related Macular Degeneration (AMD. However, harvesting RPE cells can be a technically complicated procedure. Our current work aimed to prepare intact differentiated iris pigment epithelial (IPE cell layers, which are easy to obtain and have the same embryonic origin and similar properties as RPE cells, on ePTFE substrates for transplantation purposes to rescue deteriorated photoreceptors in AMD. Methods: IPE cells isolated from rat eyes were seeded on different substrates, including fibronectin n-heptylamine (HA ePTFE substrates, HA ePTFE substrates, ePTFE substrates and fibronectin tissue culture polystyrene (TCPS as control. Cell number and morphology were assessed at each time interval. The formation of tight junction was examined by immunostaining of junction proteins. Results: An obvious increasing trend of cell number was observed in IPE cells on fibronectin n-heptylamine (HA ePTFE substrate, exhibiting heavy pigmentation and epithelial morphology. At Day 28, tight junction formation was indicated by cell-cell junctional proteins along cell borders. Conclusion: Harvested IPE cells cultured on fibronectin HA-ePTFE substrates can differentiate and form a cell monolayer that may be suitable for transplantation.

  5. Scalable bonding of nanofibrous polytetrafluoroethylene (PTFE) membranes on microstructures

    Science.gov (United States)

    Mortazavi, Mehdi; Fazeli, Abdolreza; Moghaddam, Saeed

    2018-01-01

    Expanded polytetrafluoroethylene (ePTFE) nanofibrous membranes exhibit high porosity (80%-90%), high gas permeability, chemical inertness, and superhydrophobicity, which makes them a suitable choice in many demanding fields including industrial filtration, medical implants, bio-/nano- sensors/actuators and microanalysis (i.e. lab-on-a-chip). However, one of the major challenges that inhibit implementation of such membranes is their inability to bond to other materials due to their intrinsic low surface energy and chemical inertness. Prior attempts to improve adhesion of ePTFE membranes to other surfaces involved surface chemical treatments which have not been successful due to degradation of the mechanical integrity and the breakthrough pressure of the membrane. Here, we report a simple and scalable method of bonding ePTFE membranes to different surfaces via the introduction of an intermediate adhesive layer. While a variety of adhesives can be used with this technique, the highest bonding performance is obtained for adhesives that have moderate contact angles with the substrate and low contact angles with the membrane. A thin layer of an adhesive can be uniformly applied onto micro-patterned substrates with feature sizes down to 5 µm using a roll-coating process. Membrane-based microchannel and micropillar devices with burst pressures of up to 200 kPa have been successfully fabricated and tested. A thin layer of the membrane remains attached to the substrate after debonding, suggesting that mechanical interlocking through nanofiber engagement is the main mechanism of adhesion.

  6. Ionizing radiation effects on ISS ePTFE jacketed cable assembly

    Science.gov (United States)

    Koontz, S. L.; Golden, J. L.; Lorenz, M. J.; Pedley, M. D.

    2003-09-01

    Polytetrafluoroethylene (PTFE), which is susceptible to embrittlement by ionizing radiation, is used as a primary material in the Mobile Transporter's (MT) Trailing Umbilical System (TUS) cable on the International Space Station (ISS). The TUS cable provides power and data service between the ISS truss and the MT. The TUS cable is normally stowed in an uptake reel and is fed out to follow the MT as it moves along rails on the ISS truss structure. For reliable electrical and mechanical performance, TUS cable polymeric materials must be capable of >3.5% elongation without cracking or breaking. The MT TUS cable operating temperature on ISS is expected to range between -100°C and +130°C. The on-orbit functional life requirement for the MT TUS cable is 10 years. Analysis and testing were performed to verify that the MT TUS cable would be able to meet full-life mechanical and electrical performance requirements, despite progressive embrittlement by the natural ionizing radiation environment. Energetic radiation belt electrons (trapped electrons) are the principal contributor to TUS cable radiation dose. TUS cable specimens were irradiated, in vacuum, with both energetic electrons and gamma rays. Electron beam energy was chosen to minimize charging effects on the non-conductive ePTFE (expanded PTFE) targets. Tensile testing was then performed, over the expected range of operating temperatures, as a function of radiation dose. When compared to the expected in-flight radiation dose/depth profile, atomic oxygen (AO) erosion of the radiation damaged TUS cable jacket surfaces is more rapid than the development of radiation induced embrittlement of the same surfaces. Additionally, the layered construction of the jacket prevents crack growth propagation, leaving the inner layer material compliant with the design elongation requirements. As a result, the TUS cable insulation design was verified to meet performance life requirements.

  7. Surgical membranes as directional delivery devices to generate tissue: testing in an ovine critical sized defect model.

    Directory of Open Access Journals (Sweden)

    Melissa L Knothe Tate

    Full Text Available Pluripotent cells residing in the periosteum, a bi-layered membrane enveloping all bones, exhibit a remarkable regenerative capacity to fill in critical sized defects of the ovine femur within two weeks of treatment. Harnessing the regenerative power of the periosteum appears to be limited only by the amount of healthy periosteum available. Here we use a substitute periosteum, a delivery device cum implant, to test the hypothesis that directional delivery of endogenous periosteal factors enhances bone defect healing.Newly adapted surgical protocols were used to create critical sized, middiaphyseal femur defects in four groups of five skeletally mature Swiss alpine sheep. Each group was treated using a periosteum substitute for the controlled addition of periosteal factors including the presence of collagen in the periosteum (Group 1, periosteum derived cells (Group 2, and autogenic periosteal strips (Group 3. Control group animals were treated with an isotropic elastomer membrane alone. We hypothesized that periosteal substitute membranes incorporating the most periosteal factors would show superior defect infilling compared to substitute membranes integrating fewer factors (i.e. Group 3>Group 2>Group 1>Control.Based on micro-computed tomography data, bone defects enveloped by substitute periosteum enabling directional delivery of periosteal factors exhibit superior bony bridging compared to those sheathed with isotropic membrane controls (Group 3>Group 2>Group 1, Control. Quantitative histological analysis shows significantly increased de novo tissue generation with delivery of periosteal factors, compared to the substitute periosteum containing a collagen membrane alone (Group 1 as well as compared to the isotropic control membrane. Greatest tissue generation and maximal defect bridging was observed when autologous periosteal transplant strips were included in the periosteum substitute.Periosteum-derived cells as well as other factors

  8. Five-Year Outcomes of Surgically Treated Symptomatic Epiretinal Membranes With and Without Internal Limiting Membrane Peeling.

    Science.gov (United States)

    Sultan, Harris; Wykoff, Charles C; Shah, Ankoor R

    2018-05-01

    The authors evaluated long-term postoperative visual outcomes and recurrence rates following surgery for symptomatic epiretinal membrane (ERM) ± internal limiting membrane (ILM) peeling. This was a retrospective, consecutive case series of 78 patients undergoing vitrectomy for symptomatic ERM between 1/2010 and 4/2012 with follow-up through at least postoperative year 5 (POY5). Outcomes included visual acuity (VA) (Snellen VA converted to logMAR), central retinal thickness (CRT; μm), and ERM recurrence. Subgroup analysis evaluated outcomes related to ILM peeling. Subgroup analysis based on ILM peeling did not find VA (20/50 [0.430 logMAR ± 0.061 logMAR; mean ± SD] vs. 20/60 [0.518 logMAR ± 0.128 logMAR] for ILM vs. non-ILM peeling respectively; P = .513) nor macular thickness (355 μm ± 13 μm vs. 360 μm ± 42 μm; P = .410) to be significantly different at POY5. Recurrence requiring surgery with and without ILM peeling was not statistically significantly different at POY5 (1.6% and 11.8%; P = .118). Vitrectomy for symptomatic ERM led to improved visual and anatomic outcomes with sustained benefit through 5 years. ILM peeling was was associated with reduced ERM recurrence, but this benefit was not statistically significant at POY5. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:296-302.]. Copyright 2018, SLACK Incorporated.

  9. Internal limiting membrane flap transposition for surgical repair of macular holes in primary surgery and in persistent macular holes.

    Science.gov (United States)

    Leisser, Christoph; Hirnschall, Nino; Döller, Birgit; Varsits, Ralph; Ullrich, Marlies; Kefer, Katharina; Findl, Oliver

    2018-03-01

    Classical or temporal internal limiting membrane (ILM) flap transposition with air or gas tamponade are current trends with the potential to improve surgical results, especially in cases with large macular holes. A prospective case series included patients with idiopathic macular holes or persistent macular holes after 23-G pars plana vitrectomy (PPV) and ILM peeling with gas tamponade. In all patients, 23-G PPV and ILM peeling with ILM flap transposition with gas tamponade and postoperative face-down position was performed. In 7 of 9 eyes, temporal ILM flap transposition combined with pedicle ILM flap could be successfully performed and macular holes were closed in all eyes after surgery. The remaining 2 eyes were converted to pedicle ILM flap transposition with macular hole closure after surgery. Three eyes were scheduled as pedicle ILM flap transposition due to previous ILM peeling. In 2 of these eyes, the macular hole could be closed with pedicle ILM flap transposition. In 3 eyes, free ILM flap transposition was performed and in 2 of these eyes macular hole could be closed after surgery, whereas in 1 eye a second surgery, performed as pedicle ILM flap transposition, was performed and led to successful macular hole closure. Use of ILM flaps in surgical repair of macular hole surgery is a new option of treatment with excellent results independent of the diameter of macular holes. For patients with persistent macular holes, pedicle ILM flap transposition or free ILM flap transposition are surgical options.

  10. Staged surgical management of gastroschisis with severe viscero-abdominal disproportion complicated by membranous intestinal obstruction

    Directory of Open Access Journals (Sweden)

    Sliepov O.

    2017-01-01

    Full Text Available Introduction. Incidence of gastroschisis (GS complicated by intestinal atresia is 4.5–12.6% of cases. 80% of this obstructions are observed in jejunoileal segment. Association of GS with intestinal atresia (GIA is usually diagnosed well, but at birth, diagnosis of atresia is often controversial. There is misdiagnosis of atresia during the initial surgery in about 12% of cases. The ideal treatment model of GIA had not already been set. Different surgical approaches were described in literature: abdominal closure modalities, terms of intestinal anastomoses creation and intestinal stomas formation remain outstanding issues. the severity of congenital defects may vary thus the tactics and strategy of surgical management as well as the ability to create primary intestinal anastomosis should be considered individually. Clinical case. GS with severe viscero-abdominal disproportion (VAD in fetus was diagnosed prenatally by ultrasonography (US at 21 week of gestation. Prenatal US follow-up monitoring and examinations were conducted. The presence of concomitant intestinal obstruction was suspected at 35 week of gestation. Regarding diagnosed malformations, according to developed in our clinic "First Minutes Surgery" tactics, operation was performed in 15 minutes after birth. During the initial surgery intestinal obstruction was not confirmed. Staged surgical management of GS was conducted. Intestinal obstruction was diagnosed and confirmed by radiography only after 21 days of age, after increasing of oral intakes volume to 15.0 ml. Jejunal web was found on surgery. Following web removal diamond-shaped anastomosis was created. During post-op period the recurrence of intestinal obstruction was not observed, full enteral nutrition was reached. The good outcome after exhibited surgical management was achieved. Conclusions. The proposed strategy and tactics of surgical management found to be effective and can be applied in the case of GS with severe VAD

  11. Vivosorb (R), Bio-Gide (R), and Gore-Tex (R) as barrier membranes in rat mandibular defects : an evaluation by microradiography and micro-CT

    NARCIS (Netherlands)

    Gielkens, Pepijn F. M.; Schortinghuis, Jurjen; de Jong, Johan R.; Raghoebar, Gerry M.; Stegenga, Boudewijn; Bos, Ruud R. M.

    Objectives: The objectives of this study were to determine whether a new degradable synthetic barrier membrane (Vivosorb (R)) composed of poly(DL-lactide-epsilon-caprolactone) (PDLLCL) can be useful in implant dentistry and to compare it with collagen and expanded polytetrafluoroethylene (ePTFE)

  12. Adhesive coatings based on melanin-like nanoparticles for surgical membranes.

    Science.gov (United States)

    Scognamiglio, Francesca; Travan, Andrea; Turco, Gianluca; Borgogna, Massimiliano; Marsich, Eleonora; Pasqua, Mattia; Paoletti, Sergio; Donati, Ivan

    2017-07-01

    Adhesive coatings for implantable biomaterials can be designed to prevent material displacement from the site of implant. In this paper, a strategy based on the use of melanin-like nanoparticles (MNPs) for the development of adhesive coatings for polysaccharidic membranes was devised. MNPs were synthesized in vitro and characterized in terms of dimensions and surface potential, as a function of pH and ionic strength. The in vitro biocompatibility of MNPs was investigated on fibroblast cells, while the antimicrobial properties of MNPs in suspension were evaluated on E. coli and S. aureus cultures. The manufacturing of the adhesive coatings was carried out by spreading MNPs over the surface of polysaccharidic membranes; the adhesive properties of the nano-engineered coating to the target tissue (intestinal serosa) were studied in simulated physiological conditions. Overall, this study opens for novel approaches in the design of naturally inspired nanostructured adhesive systems. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Wound Healing and ndash; A Proteomic Analysis of the Effect of Erythropoietin on Granulation Tissue Isolated from ePTFE Implants

    Directory of Open Access Journals (Sweden)

    Bekka Christensen

    2014-02-01

    Conclusion: Daily injection of recombinant human erythropoietin of 1000 IU/kg alters the protein expression of GAPDH, ENOA and TPIS in granulation tissue from wounds on postoperative day 9. The successful combination of proteomic analysis of wound tissue and the ePTFE wound model could advance our knowledge of the complex healing process. [Arch Clin Exp Surg 2014; 3(1.000: 26-33

  14. In vitro evaluation of electrospun chitosan mats crosslinked with genipin as guided tissue regeneration barrier membranes

    Science.gov (United States)

    Norowski, Peter Andrew, Jr.

    Guided tissue regeneration (GTR) is a surgical technique commonly used to exclude bacteria and soft tissues from bone graft sites in oral/maxillofacial bone graft sites by using a barrier membrane to maintain the graft contour and space. Current clinical barrier membrane materials based on expanded polytetrafluoroethylene (ePTFE) and bovine type 1 collagen are non-ideal and experience a number of disadvantages including membrane exposure, bacterial colonization/biofilm formation and premature degradation, all of which result in increased surgical intervention and poor bone regeneration. These materials do not actively participate in tissue regeneration, however bioactive materials, such as chitosan, may provide advantages such as the ability to stimulate wound healing and de novo bone formation. Our hypothesis is that electrospun chitosan GTR membranes will support cell attachment and growth but prevent cell infiltration/penetration of membrane, demonstrate in vitro degradation predictive of 4--6 month in vivo functionality, and will deliver antibiotics locally to prevent/inhibit periopathogenic complications. To test this hypothesis a series of chitosan membranes were electrospun, in the presence or absence of genipin, a natural crosslinking agent, at concentrations of 5 and 10 mM. These membranes were characterized by scanning electron microscopy, tensile testing, suture pullout testing, Fourier transform infrared spectroscopy, X-ray diffraction, and gel permeation chromatography, and in vitro biodegradation for diameter/morphology of fibers, membrane strengths, degree of crosslinking, crystallinity, molecular weight, and degradation kinetics, respectively. Cytocompability of membranes was evaluated in osteoblastic, fibroblastic and monocyte cultures. The activity of minocycline loaded and released from the membranes was determined in zone of inhibition tests using P. gingivalis microbe. The results demonstrated that genipin crosslinking extended the in vitro

  15. A surgical simulator for peeling the inner limiting membrane during wet conditions.

    Science.gov (United States)

    Omata, Seiji; Someya, Yusei; Adachi, Shyn'ya; Masuda, Taisuke; Hayakawa, Takeshi; Harada, Kanako; Mitsuishi, Mamoru; Totsuka, Kiyohito; Araki, Fumiyuki; Takao, Muneyuki; Aihara, Makoto; Arai, Fumihito

    2018-01-01

    The present study was performed to establish a novel ocular surgery simulator for training in peeling of the inner limited membrane (ILM). This simulator included a next-generation artificial ILM with mechanical properties similar to the natural ILM that could be peeled underwater in the same manner as in actual surgery. An artificial eye consisting of a fundus and eyeball parts was fabricated. The artificial eye was installed in the eye surgery simulator. The fundus part was mounted in the eyeball, which consisted of an artificial sclera, retina, and ILM. To measure the thickness of the fabricated ILM on the artificial retina, we calculated the distance of the step height as the thickness of the artificial ILM. Two experienced ophthalmologists then assessed the fabricated ILM by sensory evaluation. The minimum thickness of the artificial ILM was 1.9 ± 0.3 μm (n = 3). We were able to perform the peeling task with the ILM in water. Based on the sensory evaluation, an ILM with a minimum thickness and 1000 degrees of polymerization was suitable for training. We installed the eye model on an ocular surgery simulator, which allowed for the performance of a sequence of operations similar to ILM peeling. In conclusion, we developed a novel ocular surgery simulator for ILM peeling. The artificial ILM was peeled underwater in the same manner as in an actual operation.

  16. SURGICAL OUTCOMES AFTER INVERTED INTERNAL LIMITING MEMBRANE FLAP VERSUS CONVENTIONAL PEELING FOR VERY LARGE MACULAR HOLES.

    Science.gov (United States)

    Narayanan, Raja; Singh, Sumit R; Taylor, Stanford; Berrocal, Maria H; Chhablani, Jay; Tyagi, Mudit; Ohno-Matsui, Kyoko; Pappuru, Rajeev R; Apte, Rajendra S

    2018-04-23

    To evaluate the anatomical and visual outcomes of inverted flap technique of peeling of internal limiting membrane (ILM) versus standard peeling of ILM for macular holes of basal diameter more than 800 μm. Patients with very large idiopathic macular holes more than 800 μm in basal diameter (ranging from 243 μm to 840 μm in minimum diameter) were retrospectively included in the study. In Group A, 18 eyes of 18 patients underwent ILM peeling using the inverted flap technique. In Group B, 18 eyes of 18 patients underwent conventional ILM peeling. The primary endpoint was the rate of hole closure at 6 months after surgery. The secondary outcome measure was the change in best-corrected visual acuity at 6 months after surgery. There were no significant differences in ocular characteristics of the study groups at baseline except for the age distribution. Mean macular hole diameter was 1,162.8 ± 206.0 μm and 1,229.6 ± 228.1 μm in Group A and Group B, respectively. The hole closure rate was 88.9% (16/18) in Group A and 77.8% (14/18) in Group B (P = 0.66). The mean gain in best-corrected visual acuity was higher in Group A than in Group B (P = 0.12) at 6 months, but this was not statistically significant. There were no severe ocular adverse events in either group. In this multicenter series, inverted ILM flap technique did not lead to significantly higher anatomical closure rates than conventional ILM peeling in large macular holes more than 800 μm in diameter.

  17. Analysis of explanted ePTFE cardiovascular grafts (modified BT shunt)

    Energy Technology Data Exchange (ETDEWEB)

    Doble, Mukesh [Department of Biotechnology, Indian Institute of Technology, Chennai 600 036 (India); Makadia, Nilesh; Pavithran, Sreeja; Kumar, R Suresh [Department of Pediatric Cardiology, Institute of Cardio-Vascular Diseases, Madras Medical Mission, Chennai, 600 037 (India)], E-mail: mukeshd@iitm.ac.in

    2008-09-01

    Structural, chemical, mechanical and surface changes were studied in expanded polytetrafluroethylene vascular grafts explanted from children undergoing planned surgical management of congenital heart disease. These grafts were implanted when recipients were aged 7 days to 8 years (median-48 weeks) and they had been in circulation for a period of 10-52 months (median-74 weeks). While no chemical changes were observed in the shunt, on average the tensile strength had decreased by 50%, total elongation by 61% and crystallinity by 3%. No salt deposits were observed on the surface of the graft. Soluble and insoluble proteins were bound to the polymer surface, which had made the surface hydrophilic. The external surface roughness had increased by 254.5 and the internal surface roughness by 2.6 times the initial value. The fine polymer structure had become fused and clumped. The fusing of strands on the polymer surface became more pronounced with longer duration of implantation. In one instance of previously documented graft stenosis, the heat capacity was found to be more than that of the unimplanted sample, indicating an increase in crystallinity. A longer period of study with a larger sample size would likely shed more light on the relation between physico-chemical changes and graft stenosis.

  18. Analysis of explanted ePTFE cardiovascular grafts (modified BT shunt)

    International Nuclear Information System (INIS)

    Doble, Mukesh; Makadia, Nilesh; Pavithran, Sreeja; Kumar, R Suresh

    2008-01-01

    Structural, chemical, mechanical and surface changes were studied in expanded polytetrafluroethylene vascular grafts explanted from children undergoing planned surgical management of congenital heart disease. These grafts were implanted when recipients were aged 7 days to 8 years (median-48 weeks) and they had been in circulation for a period of 10-52 months (median-74 weeks). While no chemical changes were observed in the shunt, on average the tensile strength had decreased by 50%, total elongation by 61% and crystallinity by 3%. No salt deposits were observed on the surface of the graft. Soluble and insoluble proteins were bound to the polymer surface, which had made the surface hydrophilic. The external surface roughness had increased by 254.5 and the internal surface roughness by 2.6 times the initial value. The fine polymer structure had become fused and clumped. The fusing of strands on the polymer surface became more pronounced with longer duration of implantation. In one instance of previously documented graft stenosis, the heat capacity was found to be more than that of the unimplanted sample, indicating an increase in crystallinity. A longer period of study with a larger sample size would likely shed more light on the relation between physico-chemical changes and graft stenosis

  19. Multi-functional electrospun antibacterial core-shell nanofibrous membranes for prolonged prevention of post-surgical tendon adhesion and inflammation.

    Science.gov (United States)

    Shalumon, K T; Sheu, Chialin; Chen, Chih-Hao; Chen, Shih-Heng; Jose, Gils; Kuo, Chang-Yi; Chen, Jyh-Ping

    2018-05-01

    The possibility of endowing an electrospun anti-adhesive barrier membrane with multi-functionality, such as lubrication, prevention of fibroblast attachment and anti-infection and anti-inflammation properties, is highly desirable for the management of post-surgical tendon adhesion. To this end, we fabricated core-shell nanofibrous membranes (CSNMs) with embedded silver nanoparticles (Ag NPs) in the poly(ethylene glycol) (PEG)/poly(caprolactone) (PCL) shell and hyaluronic acid (HA)/ibuprofen in the core. HA imparted a lubrication effect for smooth tendon gliding and reduced fibroblast attachment, while Ag NPs and ibuprofen functioned as anti-infection and anti-inflammation agents, respectively. CSNMs with a PEG/PCL/Ag shell (PPA) and HA core containing 0% (H/PPA), 10% (HI10/PPA), 30% (HI30/PPA) and 50% (HI50/PPA) ibuprofen were fabricated through co-axial electrospinning and assessed through microscopic, spectroscopic, thermal, mechanical and drug release analyses. Considering nutrient passage through the barrier, the microporous CSNMs exerted the same barrier effect but drastically increased the mass transfer coefficients of bovine serum albumin compared with the commercial anti-adhesive membrane SurgiWrap®. Cell attachment/focal adhesion formation of fibroblasts revealed effective reduction of initial cell attachment on the CSNM surface with minimum cytotoxicity (except HI50/PPA). The anti-bacterial effect against both Gram-negative and Gram-positive bacteria was verified to be due to the Ag NPs in the membranes. In vivo studies using H/PPA and HI30/PPA CSNMs and SurgiWrap® in a rabbit flexor tendon rupture model demonstrated the improved efficacy of HI30/PPA CSNMs in reducing inflammation and tendon adhesion formation based on gross observation, histological analysis and functional assays. We conclude that HI30/PPA CSNMs can act as a multifunctional barrier membrane to prevent peritendinous adhesion after tendon surgery. A multi-functional anti-adhesion barrier

  20. SURGICAL REMOVAL OF EPIRETINAL MEMBRANE WITH AND WITHOUT REMOVAL OF INTERNAL LIMITING MEMBRANE: Comparative Study of Visual Acuity, Features of Optical Coherence Tomography, and Recurrence Rate.

    Science.gov (United States)

    De Novelli, Fernando J; Goldbaum, Mauro; Monteiro, Mario L R; Bom Aggio, Fabio; Takahashi, Walter Y

    2017-12-05

    To study and compare visual acuity, foveal thickness, outer limiting layer, ellipsoid zone, and recurrence rate in patients undergoing removal of the epiretinal membrane with and without the removal of the internal limiting membrane (ILM). Sixty-three patients who had the epiretinal membrane removed by a single surgeon were randomly assigned into 2 groups: Group 1 without additional removal of the ILM and Group 2 with removal of the ILM. Patients were followed up and evaluated at the first month, third month, and sixth month, postoperatively. Patients from both groups had a gradual improvement in their vision over time. There was no significant difference in the improvement in visual acuity between the two groups. About tomographic assessment of alterations, no significant differences were found between the groups; however, Group 1 had a higher relapse rate (17%) compared with Group 2 (3.6%) (P = 0.09). Epiretinal membrane removal with and without ILM peeling shows similar functional and anatomical improvements, but the group in which the ILM was not removed seemed to have a higher recurrence rate.

  1. Performance of a 1 kW Class Nafion-PTFE Composite Membrane Fuel Cell Stack

    Directory of Open Access Journals (Sweden)

    Pattabiraman Krishnamurthy

    2012-01-01

    Full Text Available Composite membranes have been prepared by impregnation of Nafion into the expanded polytetrafluoroethylene (EPTFE matrix. Nafion loading in the composite membranes was kept constant at 2 mg/cm2. The lower amount of electrolyte per unit area in the composite membranes offers cost advantages compared to conventional membrane of 50 μm thickness with an electrolyte loading of ~9 mg/cm2. Composite membranes (30 μm thickness were found to have higher thermal stability and mechanical strength compared to the conventional membranes (50 μm thickness. The performance of the membrane electrode assembly made with these composite membranes was comparable to that of the conventional membranes. Single cells fabricated from these MEAs were tested for their performance and durability before scaling them up for large area. The performance of a 20-cell stack of active area 330 cm2 fabricated using these membranes is reported.

  2. Combined HLA matched limbal stem cells allograft with amniotic membrane transplantation as a prophylactic surgical procedure to prevent corneal graft rejection after penetrating keratoplasty: case report

    Directory of Open Access Journals (Sweden)

    Paolo Capozzi

    2014-09-01

    Full Text Available Purpose. To determine if the use of combined HLA matched limbal stem cells allograft with amniotic membrane transplantation (AMT is a safe and effective prophylactic surgical procedure to prevent corneal graft after penetrating keratoplasty (PK. Methods. We report the case of a 17 years old patient with a history of congenital glaucoma, trabeculectomy and multiple corneal graft rejections, presenting total limbal cell deficiency. To reduce the possibility of graft rejection in the left eye after a new PK, a two step procedure was performed. At first the patient underwent a combined HLA matched limbal stem cells allograft (LAT and AMT and then, 10 months later, a new PK. Results. During 12 months of follow-up, the corneal graft remained stable and smooth, with no sign of graft rejection. Conclusions. In our patient, the prophylactic use of LAT from HLA-matched donors and AMT before PK, may result in a better prognosis of corneal graft survival.

  3. Recovery of ammonia from poultry litter using flat gas permeable membranes.

    Science.gov (United States)

    Rothrock, M J; Szögi, A A; Vanotti, M B

    2013-06-01

    The use of flat gas-permeable membranes was investigated as components of a new process to capture and recover ammonia (NH3) in poultry houses. This process includes the passage of gaseous NH3 through a microporous hydrophobic membrane, capture with a circulating dilute acid on the other side of the membrane, and production of a concentrated ammonium (NH4) salt. Bench- and pilot-scale prototype systems using flat expanded polytetrafluoroethylene (ePTFE) membranes and a sulfuric acid solution consistently reduced headspace NH3 concentrations from 70% to 97% and recovered 88% to 100% of the NH3 volatilized from poultry litter. The potential benefits of this technology include cleaner air inside poultry houses, reduced ventilation costs, and a concentrated liquid ammonium salt that can be used as a plant nutrient solution. Published by Elsevier Ltd.

  4. Surgical Assisting

    Science.gov (United States)

    ... instruction, including: Microbiology Pathophysiology Pharmacology Anatomy and physiology Medical terminology Curriculum . Course content includes: Advanced surgical anatomy Surgical microbiology Surgical pharmacology Anesthesia methods and agents Bioscience Ethical ...

  5. Abortion - surgical

    Science.gov (United States)

    Suction curettage; Surgical abortion; Elective abortion - surgical; Therapeutic abortion - surgical ... Surgical abortion involves dilating the opening to the uterus (cervix) and placing a small suction tube into the uterus. ...

  6. Surgical lighting

    NARCIS (Netherlands)

    Knulst, A.J.

    2017-01-01

    The surgical light is an important tool for surgeons to create and maintain good visibility on the surgical task. Chapter 1 gives background to the field of (surgical) lighting and related terminology. Although the surgical light has been developed strongly since its introduction a long time ago,

  7. Surgical smoke.

    Science.gov (United States)

    Fan, Joe King-Man; Chan, Fion Siu-Yin; Chu, Kent-Man

    2009-10-01

    Surgical smoke is the gaseous by-product formed during surgical procedures. Most surgeons, operating theatre staff and administrators are unaware of its potential health risks. Surgical smoke is produced by various surgical instruments including those used in electrocautery, lasers, ultrasonic scalpels, high speed drills, burrs and saws. The potential risks include carbon monoxide toxicity to the patient undergoing a laparoscopic operation, pulmonary fibrosis induced by non-viable particles, and transmission of infectious diseases like human papilloma virus. Cytotoxicity and mutagenicity are other concerns. Minimisation of the production of surgical smoke and modification of any evacuation systems are possible solutions. In general, a surgical mask can provide more than 90% protection to exposure to surgical smoke; however, in most circumstances it cannot provide air-tight protection to the user. An at least N95 grade or equivalent respirator offers the best protection against surgical smoke, but whether such protection is necessary is currently unknown.

  8. Um novo substituto vascular: arterioplastia femoral em cães com remendo de membrana de biopolímero de cana-de-açúcar - avaliação hemodinâmica e histopatológica A new vascular substitute: femoral artery angioplasty in dogs using sugarcane biopolymer membrane patch - hemodynamic and histopathologic evaluation

    Directory of Open Access Journals (Sweden)

    Silvio Romero de Barros Marques

    2007-12-01

    right side. The dogs underwent daily clinical evaluation for the first week and weekly thereafter. Clinical evaluation consisted of an examination of femoral artery pulses, gait assessment and verification as to whether there was any pulsatile tumor, bruising, hemorrhage or surgical wound infection. One hundred and eighty days after the angioplasties, percutaneous Doppler velocimetry of the femoral arteries was performed under general anesthesia. Next, the dogs underwent dissection of the femoral arteries, measurement of the arterial diameter and perioperative Doppler velocimetry proximally and distally to the artery angioplasty. Laparotomy was then performed to expose the abdominal aorta for angiographic access. The femoral artery segments with patches were harvested for histopathologic analysis, and the animals were sacrificed under a toxic dosage of anesthetic. RESULTS: At 180 days, no cases of surgical wound infection, aneurysm, rupture, pseudoaneurysm or thrombosis were observed in either group. A chronic inflammatory reaction with lymphocytes and neutrophils was seen in both groups on the outer surface of patches. Fibrosis was seen on the inner and outer surfaces of the patches. Invasion by fibroblasts of all e-PTFE patches occurred in the control group. CONCLUSIONS: Based on the results obtained with the experimental model employed, for a 180-day period, it may be concluded that the sugarcane biopolymer membrane is an adequate arterial substitute when used as a patch in femoral artery angioplasty in dogs.

  9. Surgical orthodontics.

    Science.gov (United States)

    Strohl, Alexis M; Vitkus, Lauren

    2017-08-01

    The article reviews some commonly used orthodontic treatments as well as new strategies to assist in the correction of malocclusion. Many techniques are used in conjunction with surgical intervention and are a necessary compliment to orthognathic surgery. Basic knowledge of these practices will aid in the surgeon's ability to adequately treat the patient. Many orthodontists and surgeons are eliminating presurgical orthodontics to adopt a strategy of 'surgery first' orthodontics in orthognathic surgery. This has the benefit of immediate improvement in facial aesthetics and shorter treatment times. The advent of virtual surgical planning has helped facilitate the development of this new paradigm by making surgical planning faster and easier. Furthermore, using intraoperative surgical navigation is improving overall precision and outcomes. A variety of surgical and nonsurgical treatments may be employed in the treatment of malocclusion. It is important to be familiar with all options available and tailor the patient's treatment plan accordingly. Surgery-first orthodontics, intraoperative surgical navigation, virtual surgical planning, and 3D printing are evolving new techniques that are producing shorter treatment times and subsequently improving patient satisfaction without sacrificing long-term stability.

  10. Membrane dynamics

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    Current topics include membrane-protein interactions with regard to membrane deformation or curvature sensing by BAR domains. Also, we study the dynamics of membrane tubes of both cells and simple model membrane tubes. Finally, we study membrane phase behavior which has important implications...... for the lateral organization of membranes as wells as for physical properties like bending, permeability and elasticity...

  11. Surgical competence.

    Science.gov (United States)

    Patil, Nivritti G; Cheng, Stephen W K; Wong, John

    2003-08-01

    Recent high-profile cases have heightened the need for a formal structure to monitor achievement and maintenance of surgical competence. Logbooks, morbidity and mortality meetings, videos and direct observation of operations using a checklist, motion analysis devices, and virtual reality simulators are effective tools for teaching and evaluating surgical skills. As the operating theater is also a place for training, there must be protocols and guidelines, including mandatory standards for supervision, to ensure that patient care is not compromised. Patients appreciate frank communication and honesty from surgeons regarding their expertise and level of competence. To ensure that surgical competence is maintained and keeps pace with technologic advances, professional registration bodies have been promoting programs for recertification. They evaluate performance in practice, professional standing, and commitment to ongoing education.

  12. Surgical Navigation

    DEFF Research Database (Denmark)

    Azarmehr, Iman; Stokbro, Kasper; Bell, R. Bryan

    2017-01-01

    Purpose: This systematic review investigates the most common indications, treatments, and outcomes of surgical navigation (SN) published from 2010 to 2015. The evolution of SN and its application in oral and maxillofacial surgery have rapidly developed over recent years, and therapeutic indicatio...

  13. Surgical Instrument

    NARCIS (Netherlands)

    Dankelman, J.; Horeman, T.

    2009-01-01

    The present invention relates to a surgical instrument for minimall-invasive surgery, comprising a handle, a shaft and an actuating part, characterised by a gastight cover surrounding the shaft, wherein the cover is provided with a coupler that has a feed- through opening with a loskable seal,

  14. Membrane fusion

    DEFF Research Database (Denmark)

    Bendix, Pól Martin

    2015-01-01

    At Stanford University, Boxer lab, I worked on membrane fusion of small unilamellar lipid vesicles to flat membranes tethered to glass surfaces. This geometry closely resembles biological systems in which liposomes fuse to plasma membranes. The fusion mechanism was studied using DNA zippering...... between complementary strands linked to the two apposing membranes closely mimicking the zippering mechanism of SNARE fusion complexes....

  15. Characterizing the Performance of Gas-Permeable Membranes as an Ammonia Recovery Strategy from Anaerobically Digested Dairy Manure.

    Science.gov (United States)

    Fillingham, Melanie; VanderZaag, Andrew; Singh, Jessica; Burtt, Stephen; Crolla, Anna; Kinsley, Chris; MacDonald, J Douglas

    2017-10-07

    Capturing ammonia from anaerobically digested manure could simultaneously decrease the adverse effects of ammonia inhibition on biogas production, reduce reactive nitrogen (N) loss to the environment, and produce mineral N fertilizer as a by-product. In this study, gas permeable membranes (GPM) were used to capture ammonia from dairy manure and digestate by the diffusion of gaseous ammonia across the membrane where ammonia is captured by diluted acid, forming an aqueous ammonium salt. A lab-scale prototype using tubular expanded polytetrafluoroethylene (ePTFE) GPM was used to (1) characterize the effect of total ammonium nitrogen (TAN) concentration, temperature, and pH on the ammonia capture rate using GPM, and (2) to evaluate the performance of a GPM system in conditions similar to a mesophilic anaerobic digester. The GPM captured ammonia at a rate between 2.2 to 6.3% of gaseous ammonia in the donor solution per day. Capture rate was faster in anaerobic digestate than raw manure. The ammonia capture rate could be predicted using non-linear regression based on the factors of total ammonium nitrogen concentration, temperature, and pH. This use of membranes shows promise in reducing the deleterious impacts of ammonia on both the efficiency of biogas production and the release of reactive N to the environment.

  16. Membrane Biophysics

    CERN Document Server

    Ashrafuzzaman, Mohammad

    2013-01-01

    Physics, mathematics and chemistry all play a vital role in understanding the true nature and functioning of biological membranes, key elements of living processes. Besides simple spectroscopic observations and electrical measurements of membranes we address in this book the phenomena of coexistence and independent existence of different membrane components using various theoretical approaches. This treatment will be helpful for readers who want to understand biological processes by applying both simple observations and fundamental scientific analysis. It provides a deep understanding of the causes and effects of processes inside membranes, and will thus eventually open new doors for high-level pharmaceutical approaches towards fighting membrane- and cell-related diseases.

  17. Orthodontic space closure in combination with membrane supported healing of extraction sockets (MHE) a pilot study.

    Science.gov (United States)

    Tiefengraber, Julia; Diedrich, Peter; Fritz, Ulrike; Lantos, Peter

    2002-09-01

    In periodontology and implantology the guided bone regeneration (GBR) technique represents a well established and successful method for augmentation of alveolar bone. The aim of the present study was to evaluate what advantages, if any, are offered for orthodontic space closure by membrane supported healing of extraction sockets (MHE) (criteria: rate of movement, incidence of gingival clefts, atrophy of the alveolar bone). Within the scope of orthodontic therapy with a complete fixed appliance, three girls aged 11-14 years with indication for extraction of the first premolars were unilaterally augmented with an e-PTFE membrane (Gore-Tex((R)), W. L. Gore & Associates, Flagstaff, AZ, USA) immediately after premolar extraction. The study was performed in the split-mouth technique. An atraumatic extraction without digital compression was performed on the control side. The membranes were fixed with a Frios((R)) fixation set (Friadent, GmbH, Mannheim, Germany) and removed after 6 to 8 weeks. 1 week after membrane removal, space closure was started simultaneously with passive rectangular segmented archwires using Sentalloy((R)) closed coil springs (GAC International, Inc., Gräfelfing, Germany) at a constant force of 200 cN. The transversal and vertical dimensions of the alveolar bone the rate of space closure were determined clinically and radiographically. Complications were not observed in any patient. The MHE-treated alveolar region showed pronounced stability of the transversal dimension. Space closure was performed in all cases without gingival clefts being induced. The control side showed distinct atrophy as well as gingival clefts. No differences were recorded in the rate of space closure. The MHE technique seems to be a suitable means of creating favorable periodontal conditions for tooth movement, especially in cases of alveolar bone loss after extraction or trauma.

  18. Micro-surgical endodontics.

    Science.gov (United States)

    Eliyas, S; Vere, J; Ali, Z; Harris, I

    2014-02-01

    Non-surgical endodontic retreatment is the treatment of choice for endodontically treated teeth with recurrent or residual disease in the majority of cases. In some cases, surgical endodontic treatment is indicated. Successful micro-surgical endodontic treatment depends on the accuracy of diagnosis, appropriate case selection, the quality of the surgical skills, and the application of the most appropriate haemostatic agents and biomaterials. This article describes the armamentarium and technical procedures involved in performing micro-surgical endodontics to a high standard.

  19. Membrane paradigm

    International Nuclear Information System (INIS)

    Price, R.H.; Thorne, K.S.

    1986-01-01

    The membrane paradigm is a modified frozen star approach to modeling black holes, with particles and fields assuming a complex, static, boundary-layer type structure (membrane) near the event horizon. The membrane has no effects on the present or future evolution of particles and fields above itself. The mathematical representation is a combination of a formalism containing terms for the shear and bulk viscosity, surface pressure, momentum, temperature, entropy, etc., of the horizon and the 3+1 formalism. The latter model considers a family of three-dimensional spacelike hypersurfaces in one-dimensional time. The membrane model considers a magnetic field threading the hole and undergoing torque from the hole rotation. The field is cleaned by the horizon and distributed over the horizon so that ohmic dissipation is minimized. The membrane paradigm is invalid inside the horizon, but is useful for theoretically probing the properties of slowly evolving black holes

  20. Membrane processes

    Science.gov (United States)

    Staszak, Katarzyna

    2017-11-01

    The membrane processes have played important role in the industrial separation process. These technologies can be found in all industrial areas such as food, beverages, metallurgy, pulp and paper, textile, pharmaceutical, automotive, biotechnology and chemical industry, as well as in water treatment for domestic and industrial application. Although these processes are known since twentieth century, there are still many studies that focus on the testing of new membranes' materials and determining of conditions for optimal selectivity, i. e. the optimum transmembrane pressure (TMP) or permeate flux to minimize fouling. Moreover the researchers proposed some calculation methods to predict the membrane processes properties. In this article, the laboratory scale experiments of membrane separation techniques, as well their validation by calculation methods are presented. Because membrane is the "heart" of the process, experimental and computational methods for its characterization are also described.

  1. Degradation analysis and modeling of reinforced catalyst coated membranes operated under OCV conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kundu, Sumit; Fowler, Michael W.; Simon, Leonardo C. [Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario (Canada); Abouatallah, Rami; Beydokhti, Natasha [Hydrogenics Corporation, 5985 McLaughlin Road, Mississauga, Ontario (Canada)

    2008-09-01

    This paper studies the degradation of Gore trademark PRIMEA {sup registered} series 5510 catalyst coated membranes with an ePTFE reinforcement layer under open circuit voltage conditions at 90 C, 75% RH, and no backpressure. Scanning electron microscopy (SEM) imaging of cross-sections revealed extensive cathode-side ionomer degradation and the presence of a platinum band. Cumulative fluoride release measurements show more fluoride exiting with the cathode effluent. Furthermore, both anode and cathode cumulative fluoride release plateau after long degradation times. Open circuit voltage was also monitored and the degradation rate was found to decrease after a long duration. It is proposed that all fluoride species are generated from the cathode-side ionomer degradation process and that the fluoride then diffuses to the anode and cathode channels. Further, once the cathode-side ionomer is consumed the degradation reaction slows as the ''degradation front'' passes through the inert reinforcement layer. This process was modeled using a semi-empirical transient model and compared to experimental results. (author)

  2. Primordial membranes

    DEFF Research Database (Denmark)

    Hanczyc, Martin M; Monnard, Pierre-Alain

    2017-01-01

    Cellular membranes, which are self-assembled bilayer structures mainly composed of lipids, proteins and conjugated polysaccharides, are the defining feature of cell physiology. It is likely that the complexity of contemporary cells was preceded by simpler chemical systems or protocells during...... the various evolutionary stages that led from inanimate to living matter. It is also likely that primitive membranes played a similar role in protocell 'physiology'. The composition of such ancestral membranes has been proposed as mixtures of single hydrocarbon chain amphiphiles, which are simpler versions...

  3. Membranous nephropathy

    Science.gov (United States)

    ... skin-lightening creams Systemic lupus erythematosus , rheumatoid arthritis, Graves disease, and other autoimmune disorders The disorder occurs at ... diagnosis. The following tests can help determine the cause of membranous nephropathy: Antinuclear antibodies test Anti-double- ...

  4. American Pediatric Surgical Association

    Science.gov (United States)

    American Pediatric Surgical Association Search for: Login Resources + For Members For Professionals For Training Program Directors For Media For ... Surgical Outcomes Surveys & Results Publications Continuing Education + ExPERT Pediatric Surgery NaT Annual Meeting CME MOC Requirements Residents / ...

  5. Abortion - surgical - aftercare

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000658.htm Abortion - surgical - aftercare To use the sharing features on ... please enable JavaScript. You have had a surgical abortion. This is a procedure that ends pregnancy by ...

  6. Urogynecologic Surgical Mesh Implants

    Science.gov (United States)

    ... procedures performed to treat pelvic floor disorders with surgical mesh: Transvaginal mesh to treat POP Transabdominal mesh to treat ... address safety risks Final Order for Reclassification of Surgical Mesh for Transvaginal Pelvic Organ Prolapse Repair Final Order for Effective ...

  7. Encapsulating peritonitis: computed tomography and surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kadow, Juliana Santos; Fingerhut, Carla Jeronimo Peres; Fernandes, Vinicius de Barros; Coradazzi, Klaus Rizk Stuhr; Silva, Lucas Marciel Soares; Penachim, Thiago Jose, E-mail: vinicius.barros.fernandes@gmail.com [Pontificia Universidade Catolica de Campinas (PUC-Campinas), Campinas, SP (Brazil). Hospital e Maternidade Celso Pierro

    2014-07-15

    Sclerosing encapsulating peritonitis is a rare and frequently severe entity characterized by total or partial involvement of small bowel loops by a membrane of fibrous tissue. The disease presents with nonspecific clinical features of intestinal obstruction, requiring precise imaging diagnosis to guide the treatment. The present report emphasizes the importance of computed tomography in the diagnosis of this condition and its confirmation by surgical correlation. (author)

  8. Axionic membranes

    International Nuclear Information System (INIS)

    Aurilia, A.; Spallucci, E.

    1992-01-01

    A metal ring removed from a soap-water solution encloses a film of soap which can be mathematically described as a minimal surface having the ring as its only boundary. This is known to everybody. In this letter we suggest a relativistic extension of the above fluidodynamic system where the soap film is replaced by a Kalb-Ramand gauge potential B μν (x) and the ring by a closed string. The interaction between the B μν field and the string current excites a new configuration of the system consisting of a relativistic membrane bounded by the string. We call such a classical solution of the equation of motion an axionic membrane. As a dynamical system, the axionic membrane admits a Hamilton-Jacobi formulation which is an extension of the HJ theory of electromagnetic strings. (orig.)

  9. Metamaterial membranes

    International Nuclear Information System (INIS)

    Restrepo-Flórez, Juan Manuel; Maldovan, Martin

    2017-01-01

    We introduce a new class of metamaterial device to achieve separation of compounds by using coordinate transformations and metamaterial theory. By rationally designing the spatial anisotropy for mass diffusion, we simultaneously concentrate different compounds in different spatial locations, leading to separation of mixtures across a metamaterial membrane. The separation of mixtures into their constituent compounds is critically important in biophysics, biomedical, and chemical applications. We present a practical case where a mixture of oxygen and nitrogen diffusing through a polymeric planar matrix is separated. This work opens doors to new paradigms in membrane separations via coordinate transformations and metamaterials by introducing novel properties and unconventional mass diffusion phenomena. (paper)

  10. Chelating polymeric membranes

    KAUST Repository

    Peinemann, Klaus-Viktor; Villalobos Vazquez de la Parra, Luis Francisco; Hilke, Roland

    2015-01-01

    microporous chelating polymeric membrane. Embodiments include, but are not limited to, microporous chelating polymeric membranes, device comprising the membranes, and methods of using and making the same.

  11. Deriving DICOM surgical extensions from surgical workflows

    Science.gov (United States)

    Burgert, O.; Neumuth, T.; Gessat, M.; Jacobs, S.; Lemke, H. U.

    2007-03-01

    The generation, storage, transfer, and representation of image data in radiology are standardized by DICOM. To cover the needs of image guided surgery or computer assisted surgery in general one needs to handle patient information besides image data. A large number of objects must be defined in DICOM to address the needs of surgery. We propose an analysis process based on Surgical Workflows that helps to identify these objects together with use cases and requirements motivating for their specification. As the first result we confirmed the need for the specification of representation and transfer of geometric models. The analysis of Surgical Workflows has shown that geometric models are widely used to represent planned procedure steps, surgical tools, anatomical structures, or prosthesis in the context of surgical planning, image guided surgery, augmented reality, and simulation. By now, the models are stored and transferred in several file formats bare of contextual information. The standardization of data types including contextual information and specifications for handling of geometric models allows a broader usage of such models. This paper explains the specification process leading to Geometry Mesh Service Object Pair classes. This process can be a template for the definition of further DICOM classes.

  12. Recognizing surgical patterns

    NARCIS (Netherlands)

    Bouarfa, L.

    2012-01-01

    In the Netherlands, each year over 1700 patients die from preventable surgical errors. Numerous initiatives to improve surgical practice have had some impact, but problems persist. Despite the introduction of checklists and protocols, patient safety in surgery remains a continuing challenge. This is

  13. Surgical medical record

    DEFF Research Database (Denmark)

    Bulow, S.

    2008-01-01

    A medical record is presented on the basis of selected linguistic pearls collected over the years from surgical case records Udgivelsesdato: 2008/12/15......A medical record is presented on the basis of selected linguistic pearls collected over the years from surgical case records Udgivelsesdato: 2008/12/15...

  14. Surgical repair of a congenital pericardial diaphragmatic hernia

    International Nuclear Information System (INIS)

    Wright, R.P.; Wright, R.; Scott, R.

    1987-01-01

    Objective: To describe the surgical repair and pre- and postoperative management of a peritoneopericardial diaphragmatic hernia (PPDH) in a pregnant dog. Case summary: A pregnant dog was presented for vomiting, lethargy, and pale mucous membranes. Pulsus paradoxus was noted on physical examination. The dog was diagnosed with a PPDH via thoracic radiographs, abdominal ultrasound, and a n echocardiogram. The hernia was surgically repaired and the dog received supportive medical care until the puppies were old enough to be delivered via cesarean section. The mother and all puppies survived. New or unique information provided: This is the first report that describes the surgical repair and postoperative management of a PPDH in a pregnant dog

  15. Epiretinal membrane negative staining and double peeling in a single block with Brilliant Blue G.

    Science.gov (United States)

    Martins, David; Neves, Pedro

    2018-01-01

    To describe a surgical technique for combined peeling of epiretinal and internal limiting membranes. The authors present their procedure of choice for epiretinal membrane surgery: negative staining effect using Brilliant Blue G and single block removal of the epiretinal and internal limiting membranes in a single step. A total of 26 eyes were operated with the described technique. In all cases, the peeling was performed successfully and with no complications. Minimum postoperative follow-up was 12 months. There were no recurrences of epiretinal membranes. The ideal surgical approach for epiretinal membranes should attempt to reduce mechanical trauma, light exposure, and dye toxicity.

  16. Surgical ethics: surgical virtue and more.

    Science.gov (United States)

    Vercler, Christian J

    2015-01-01

    The encounter between a patient and her surgeon is unique for several reasons. The surgeon inflicts pain upon a patient for the patient's own good. An operative intervention is irreducibly personal, such that the decisions about and performance of operations are inseparable from the idiosyncrasies of the individual surgeon. Furthermore, there is a chasm of knowledge between the patient and surgeon that is difficult to cross. Hence, training in the discipline of surgery includes the inculcation of certain virtues and practices to safeguard against abuses of this relationship and to make sure that the best interests of the patient are prioritized. The stories in this issue are evidence that in contemporary practice this is not quite enough, as surgeons reflect on instances they felt were ethically challenging. Common themes include the difficulty in communicating surgical uncertainty, patient-surgeon relationships, ethical issues in surgical training, and the impact of the technological imperative on caring for dying patients.

  17. Surgical site infections

    African Journals Online (AJOL)

    Decrease the inflammatory response Vasodilatation leads to better perfusion and ... Must NOT be allowed to come in contact with brain, meninges, eyes or .... project (SCIP): Evolution of National Quality Measure. Surgical. Infection 2008 ...

  18. Surgical Critical Care Initiative

    Data.gov (United States)

    Federal Laboratory Consortium — The Surgical Critical Care Initiative (SC2i) is a USU research program established in October 2013 to develop, translate, and validate biology-driven critical care....

  19. Ambulatory Surgical Measures - Facility

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Ambulatory Surgical Center Quality Reporting (ASCQR) Program seeks to make care safer and more efficient through quality reporting. ASCs eligible for this...

  20. Surgical Management of Hemorrhoids

    Science.gov (United States)

    Agbo, S. P.

    2011-01-01

    Hemorrhoids are common human afflictions known since the dawn of history. Surgical management of this condition has made tremendous progress from complex ligation and excision procedures in the past to simpler techniques that allow the patient to return to normal life within a short period. Newer techniques try to improve on the post-operative complications of older ones. The surgical options for the management of hemorrhoids today are many. Capturing all in a single article may be difficult if not impossible. The aim of this study therefore is to present in a concise form some of the common surgical options in current literature, highlighting some important post operative complications. Current literature is searched using MEDLINE, EMBASE and the Cochrane library. The conclusion is that even though there are many surgical options in the management of hemorrhoids today, most employ the ligature and excision technique with newer ones having reduced post operative pain and bleeding. PMID:22413048

  1. Surgical site infections

    African Journals Online (AJOL)

    Surgical site infections (SSIs) are a worldwide problem that has ... deep tissue is found on clinical examination, re-opening, histopathological or radiological investigation ..... Esposito S, Immune system and SSI, Journal of Chemotherapy, 2001.

  2. Surgical management of pain

    African Journals Online (AJOL)

    If these therapies fail, and with a thorough multidisciplinary approach involving carefully ... Generally, surgical pain management is divided into neuro- modulative .... 9 suggested. It is important to be sure that the underlying instability or.

  3. [Simulation in surgical training].

    Science.gov (United States)

    Nabavi, A; Schipper, J

    2017-01-01

    Patient safety during operations hinges on the surgeon's skills and abilities. However, surgical training has come under a variety of restrictions. To acquire dexterity with decreasingly "simple" cases, within the legislative time constraints and increasing expectations for surgical results is the future challenge. Are there alternatives to traditional master-apprentice learning? A literature review and analysis of the development, implementation, and evaluation of surgical simulation are presented. Simulation, using a variety of methods, most important physical and virtual (computer-generated) models, provides a safe environment to practice basic and advanced skills without endangering patients. These environments have specific strengths and weaknesses. Simulations can only serve to decrease the slope of learning curves, but cannot be a substitute for the real situation. Thus, they have to be an integral part of a comprehensive training curriculum. Our surgical societies have to take up that challenge to ensure the training of future generations.

  4. Polymeric membranes for guided bone regeneration.

    Science.gov (United States)

    Gentile, Piergiorgio; Chiono, Valeria; Tonda-Turo, Chiara; Ferreira, Ana M; Ciardelli, Gianluca

    2011-10-01

    In this review, different barrier membranes for guided bone regeneration (GBR) are described as a useful surgical technique to enhance bone regeneration in damaged alveolar sites before performing implants and fitting other dental appliances. The GBR procedure encourages bone regeneration through cellular exclusion and avoids the invasion of epithelial and connective tissues that grow at the defective site instead of bone tissue. The barrier membrane should satisfy various properties, such as biocompatibility, non-immunogenicity, non-toxicity, and a degradation rate that is long enough to permit mechanical support during bone formation. Other characteristics such as tissue integration, nutrient transfer, space maintenance and manageability are also of interest. In this review, various non-resorbable and resorbable commercially available membranes are described, based on expanded polytetrafluoroethylene, poly(lactic acid), poly(glycolic acid) and their copolymers. The polyester-based membranes are biodegradable, permit a single-stage procedure, and have higher manageability than non-resorbable membranes; however, they have shown poor biocompatibility. In contrast, membranes based on natural materials, such as collagen, are biocompatible but are characterized by poor mechanical properties and stability due to their early degradation. Moreover, new approaches are described, such as the use of multi-layered, graft-copolymer-based and composite membranes containing osteoconductive ceramic fillers as alternatives to conventional membranes. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Tympanosclerosis of the middle ear: radiologic-surgical correlation

    International Nuclear Information System (INIS)

    Moon, Won Jin; Park, Dong Woo; Lee, Seung Ro; Seong, Jin Yong; Song, Soon Young; Hahm, Chang Kok; Kim, Yong Soo; Park, Choong Ki; Tae, Kyung

    1998-01-01

    Tympanosclerosis is a common problem causing conductive hearing loss accompanied by chronic otitis media. The purpose of this study was to evaluate the CT findings of tympanosclerosis, and correlate them with the surgical findings. The CT scans of 17 patients with surgically-proven tympanosclerosis and those of a control group of 34 patients with nontympanosclerotic chronic otitis media were reviewed. According to their location, they were assigned to one of three groups; tympanic membrane, epitympanum, or ossicles. Tympanosclerosis usually appears on CT as ossicular thickening, narrowing of the epitympanum, calcification of the tympanic membrane and/or tympanic cavity. CT is very helpful in evaluating ossicular involvement and determining the appropriate surgical treatment of tympanosclerosis. (author). 13 refs., 4 figs

  6. Tympanosclerosis of the middle ear: radiologic-surgical correlation

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Won Jin; Park, Dong Woo; Lee, Seung Ro; Seong, Jin Yong; Song, Soon Young; Hahm, Chang Kok; Kim, Yong Soo; Park, Choong Ki; Tae, Kyung [Hanyang Univ., Seoul (Korea, Republic of). Coll. of Medicine

    1998-02-01

    Tympanosclerosis is a common problem causing conductive hearing loss accompanied by chronic otitis media. The purpose of this study was to evaluate the CT findings of tympanosclerosis, and correlate them with the surgical findings. The CT scans of 17 patients with surgically-proven tympanosclerosis and those of a control group of 34 patients with nontympanosclerotic chronic otitis media were reviewed. According to their location, they were assigned to one of three groups; tympanic membrane, epitympanum, or ossicles. Tympanosclerosis usually appears on CT as ossicular thickening, narrowing of the epitympanum, calcification of the tympanic membrane and/or tympanic cavity. CT is very helpful in evaluating ossicular involvement and determining the appropriate surgical treatment of tympanosclerosis. (author). 13 refs., 4 figs.

  7. Subaortic membrane mimicking hypertrophic cardiomyopathy.

    Science.gov (United States)

    Anderson, Mark Joseph; Arruda-Olson, Adelaide; Gersh, Bernard; Geske, Jeffrey

    2015-11-04

    A 34-year-old man was referred for progressive angina and exertional dyspnoea refractory to medical therapy, with a presumptive diagnosis of hypertrophic cardiomyopathy (HCM). Transthoracic echocardiography (TTE) revealed asymmetric septal hypertrophy without systolic anterior motion of the mitral valve leaflet and with no dynamic left ventricular outflow tract (LVOT) obstruction. However, the LVOT velocity was elevated at rest as well as with provocation, without the characteristic late peaking obstruction seen in HCM. Focused TTE to evaluate for suspected fixed obstruction demonstrated a subaortic membrane 2.2 cm below the aortic valve. Coronary CT angiography confirmed the presence of the subaortic membrane and was negative for concomitant coronary artery disease. Surgical resection of the subaortic membrane and septal myectomy resulted in significant symptomatic relief and lower LVOT velocities on postoperative TTE. This case reminds the clinician to carefully evaluate for alternative causes of LVOT obstruction, especially subaortic membrane, as a cause of symptoms mimicking HCM. 2015 BMJ Publishing Group Ltd.

  8. Surgical treatment of oral leukoplakia

    Directory of Open Access Journals (Sweden)

    Yuliia Kolenko

    2017-04-01

    Full Text Available Background: The effectiveness of care for patients with leukoplakia depends on how timely and accurately the disease was diagnosed and also by the subsequent choice of the optimal method of treatment. In recent decades, surgery is increasingly using methods that are alternative to standard surgical methods. Purpose: to justify, develop and evaluate treatment algorithm of verrucous and erosive-ulcerative forms of oral leukoplakia with a SIN2 histological structure. Materials and Methods: to achieve this goal, a comprehensive clinical and laboratory examination of 155 patients with oral leukoplakia was performed, which appealed to the Department of Therapeutic Dentistry of the  Bogomolets National Medical University in the period from 2011 to 2015. All patients underwent clinical and laboratory tests. Results: after removal of the affected area of the mucosa by radiation of an erbium laser, wound healing under fibrinous plaque was observed at 7.0 ± 0.5 days. When excision of the mucous membrane with a scalpel, the healing took place under the iodinine swab through the granulation phase for 14.0 ± 1.5 days. In patients after the operation of excision of the area of verrucous or erosive-ulcerative oral mucosa leukoplakia with laser radiation without antimicrobial and anti-inflammatory therapy on the third day, in 95% of cases there is no pain syndrome and collateral edema in the postoperative area. After traditional treatment, despite the use of antibiotics and non-steroidal anti-inflammatory drugs, 56% of patients complained of pain, and 62% had collateral edema. Conclusions: the use of ErrYAG laser laser radiation in the surgical treatment of patients with verrucous and erosive-ulcerative forms of leukoplakia promotes acceleration of healing processes of a postoperative wound twice as fast as in the control group. The use of laser technology reduces the risk of inflammatory purulent complications and helps to prevent the recurrence of the

  9. Robotic membranes

    DEFF Research Database (Denmark)

    Ramsgaard Thomsen, Mette

    2008-01-01

    The relationship between digital and analogue is often constructed as one of opposition. The perception that the world is permeated with underlying patterns of data, describing events and matter alike, suggests that information can be understood apart from the substance to which it is associated......, and that its encoded logic can be constructed and reconfigured as an isolated entity. This disembodiment of information from materiality implies that an event like a thunderstorm, or a material like a body, can be described equally by data, in other words it can be read or written. The following prototypes......, Vivisection and Strange Metabolisms, were developed at the Centre for Information Technology and Architecture (CITA) at the Royal Danish Academy of Fine Arts in Copenhagen as a means of engaging intangible digital data with tactile physical material. As robotic membranes, they are a dual examination...

  10. Post surgical complications from students' large animal surgical ...

    African Journals Online (AJOL)

    A retrospective study of post surgical complications was conducted on records of students' Large Animal Surgical Laboratories in the Faculty of Veterinary Medicine (F.V.M.), Ahmadu Bello University (A.B.U), Zaria from 1989 to 1993. Three hundred and eleven surgical complications were recorded from five surgical ...

  11. Efficacy of Surgical Airway Plasty for Benign Airway Stenosis.

    Science.gov (United States)

    Tsukioka, Takuma; Takahama, Makoto; Nakajima, Ryu; Kimura, Michitaka; Inoue, Hidetoshi; Yamamoto, Ryoji

    2016-01-01

    Long-term patency is required during treatment for benign airway stenosis. This study investigated the effectiveness of surgical airway plasty for benign airway stenosis. Clinical courses of 20 patients, who were treated with surgical plasty for their benign airway stenosis, were retrospectively investigated. Causes of stenosis were tracheobronchial tuberculosis in 12 patients, post-intubation stenosis in five patients, malacia in two patients, and others in one patient. 28 interventional pulmonology procedures and 20 surgical plasty were performed. Five patients with post-intubation stenosis and four patients with tuberculous stenosis were treated with tracheoplasty. Eight patients with tuberculous stenosis were treated with bronchoplasty, and two patients with malacia were treated with stabilization of the membranous portion. Anastomotic stenosis was observed in four patients, and one to four additional treatments were required. Performance status, Hugh-Jones classification, and ventilatory functions were improved after surgical plasty. Outcomes were fair in patients with tuberculous stenosis and malacia. However, efficacy of surgical plasty for post-intubation stenosis was not observed. Surgical airway plasty may be an acceptable treatment for tuberculous stenosis. Patients with malacia recover well after surgical plasty. There may be untreated patients with malacia who have the potential to benefit from surgical plasty.

  12. 3D Surgical Simulation

    Science.gov (United States)

    Cevidanes, Lucia; Tucker, Scott; Styner, Martin; Kim, Hyungmin; Chapuis, Jonas; Reyes, Mauricio; Proffit, William; Turvey, Timothy; Jaskolka, Michael

    2009-01-01

    This paper discusses the development of methods for computer-aided jaw surgery. Computer-aided jaw surgery allows us to incorporate the high level of precision necessary for transferring virtual plans into the operating room. We also present a complete computer-aided surgery (CAS) system developed in close collaboration with surgeons. Surgery planning and simulation include construction of 3D surface models from Cone-beam CT (CBCT), dynamic cephalometry, semi-automatic mirroring, interactive cutting of bone and bony segment repositioning. A virtual setup can be used to manufacture positioning splints for intra-operative guidance. The system provides further intra-operative assistance with the help of a computer display showing jaw positions and 3D positioning guides updated in real-time during the surgical procedure. The CAS system aids in dealing with complex cases with benefits for the patient, with surgical practice, and for orthodontic finishing. Advanced software tools for diagnosis and treatment planning allow preparation of detailed operative plans, osteotomy repositioning, bone reconstructions, surgical resident training and assessing the difficulties of the surgical procedures prior to the surgery. CAS has the potential to make the elaboration of the surgical plan a more flexible process, increase the level of detail and accuracy of the plan, yield higher operative precision and control, and enhance documentation of cases. Supported by NIDCR DE017727, and DE018962 PMID:20816308

  13. Anxiety in veterinary surgical students

    DEFF Research Database (Denmark)

    Langebæk, Rikke; Eika, Berit; Jensen, Asger Lundorff

    2012-01-01

    The surgical educational environment is potentially stressful and this can negatively affect students' learning. The aim of this study was to investigate whether veterinary students' level of anxiety is higher in a surgical course than in a non-surgical course and if pre-surgical training...... in a Surgical Skills Lab (SSL) has an anxiety reducing effect. Investigations were carried out as a comparative study and a parallel group study. Potential participants were fourth-year veterinary students who attended a surgical course (Basic Surgical Skills) and a non-surgical course (Clinical Examination...... and 28 students from 2010). Our results show that anxiety levels in veterinary students are significantly higher in a surgical course than in a non-surgical course (p...

  14. SURGICAL SITE INFECTION: REVIEW

    Directory of Open Access Journals (Sweden)

    P. H. M. Bonai

    2016-07-01

    Full Text Available Nosocomial infection or nosocomial infection (NI is one of the factors that increase the cost of maintaining patients in the health system, even in processes that should safely occur, such as hospital patients and performing simple and routine surgical procedures surgical centers and clinics leading to complications resulting from these infections that prolong hospital stay and promote pain and suffering to the patient, resulting in the defense of the quality of services and influencing negatively the hospitals. Therefore, the aim of this study was to review the factors that result in surgical site infection, with the purpose of better understanding of the subject and the possibility of preventive actions to better treatment outcome of the patient.

  15. Retained surgical sponge

    International Nuclear Information System (INIS)

    Koyama, Masashi; Kurono, Kenji; Iida, Akihiko; Suzuki, Hirochika; Hara, Masaki; Mizutani, Hirokazu; Ohba, Satoru; Mizutani, Masaru; Nakajima, Yoichiro.

    1993-01-01

    The CT, US, and MRI findings of confirmed retained surgical sponges were reviewed. The CT examinations in eight lesions demonstrated round or oval masses with heterogeneous internal structures. The US examinations in 5 lesions demonstrated low echogenic masses with high echogenic internal structures, which suggested retained surgical sponges. MR imagings in three lesions showed slightly high intensity comparable to that of muscles on T1-weighted images and high signal intensity on T2-weighted images, suggesting fluid collections of high protein concentration. (author)

  16. Recent advances on polymeric membranes for membrane reactors

    KAUST Repository

    Buonomenna, M. G.; Choi, Seung Hak

    2012-01-01

    . The successful use of membranes in membrane reactors is primary the result of two developments concerning: (i) membrane materials and (ii) membrane structures. The selection of a suited material and preparation technique depends on the application the membrane

  17. Surgical infections with Mycoplasma

    DEFF Research Database (Denmark)

    Levi-Mazloum, Niels Donald; Prag, Jørgen Brorson; Jensen, J S

    1997-01-01

    Mycoplasma hominis and Ureaplasma urealyticum are common inhabitants of the human genital tract. Evidence for an aetiological role in pyelonephritis, pelvic inflammatory disease, post-abortion and post-partum fever has been presented. There are sporadic reports of Mycoplasma causing serious...... extragenital infection such as septicemia, septic arthritis, neonatal meningitis and encephalitis. We review 38 cases of surgical infections with Mycoplasma....

  18. [Surgical therapy of gynecomastia].

    Science.gov (United States)

    Heckmann, A; Leclère, F M; Vogt, P M; Steiert, A

    2011-09-01

    Nowadays surgical intervention is an essential part of the treatment of idiopathic gynecomastia. Choosing the right method is crucial and is based on the current status in the clinical and histological evaluation. Before finalizing the process of choosing a specific method a prior interdisciplinary evaluation of the patient is necessary to ascertain clear indications for a surgical intervention. Liposuction is one of the methods which have become popular in recent years. The advantages are the possible combination with traditional techniques, such as subcutaneous mastectomy or periareolar mastopexy. The main indication is for gynecomastia stage IIa/b and is justifiable due to the reduction in surgical complications and scarring. Furthermore this technique provides an excellent aesthetical outcome for the patient. A total of 162 patients suffering from gynecomastia stages I-III (according to Simon) were surgically treated between 2000 and 2010 and these cases were retrospectively evaluated. The results showed a decline in the use of a T-shaped incision in combination with subcutaneous mastectomy with periareolar tightening compared to an increase in the use of subcutaneous mastectomy in combination with liposuction. The excised tissue should always be sent for histological examination to make sure no malignant cells were present.

  19. Surgical manifestations of filariasis

    Directory of Open Access Journals (Sweden)

    Subrahmanyam M

    1978-01-01

    Full Text Available Surgical manifestations of filariasis as seen in 150 cases over a period of three years in the department of Surgery, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha are reviewed. The genital manifestations are more common than the elephantiasis in this endemic zone.

  20. Improving surgical weekend handover.

    Science.gov (United States)

    Culwick, Caroline; Devine, Chris; Coombs, Catherine

    2014-01-01

    Effective handovers are vital to patient safety and continuity of care, and this is recognised by several national bodies including the GMC. The existing model at Great Western Hospital (GWH) involved three general surgical teams and a urology team placing their printed patient lists, complete with weekend jobs, in a folder for the on-call team to collect at the weekend. We recognised a need to reduce time searching for patients, jobs and reviews, and to streamline weekend ward rounds. A unified weekend list ordering all surgical patients by ward and bed number was introduced. Discrepancies in the layout of each team's weekday list necessitated the design of a new weekday list to match the weekend list to facilitate the easy transfer of information between the two lists. A colour coding system was also used to highlight specific jobs. Prior to this improvement project only 7.1% of those polled were satisfied with the existing system, after a series of interventions satisfaction increased to 85.7%. The significant increase in overall satisfaction with surgical handover following the introduction of the unified weekend list is promising. Locating patients and identifying jobs is easier and weekend ward rounds can conducted in a more logical and timely fashion. It has also helped facilitate the transition to consultant ward rounds of all surgical inpatients at the weekends with promising feedback from a recent consultants meeting.

  1. [Surgical complications of colostomies].

    Science.gov (United States)

    Ben Ameur, Hazem; Affes, Nejmeddine; Rejab, Haitham; Abid, Bassem; Boujelbene, Salah; Mzali, Rafik; Beyrouti, Mohamed Issam

    2014-07-01

    The colostomy may be terminal or lateral, temporary or permanent. It may have psychological, medical or surgical complications. reporting the incidence of surgical complications of colostomies, their therapeutic management and trying to identify risk factors for their occurrence. A retrospective study for a period of 5 years in general surgery department, Habib Bourguiba hospital, Sfax, including all patients operated with confection of a colostomy. Were then studied patients reoperated for stoma complication. Among the 268 patients who have had a colostomy, 19 patients (7%) developed surgical stoma complications. They had a mean age of 59 years, a sex ratio of 5.3 and a 1-ASA score in 42% of cases. It was a prolapse in 9 cases (reconfection of the colostomy: 6 cases, restoration of digestive continuity: 3 cases), a necrosis in 5 cases (reconfection of the colostomy), a plicature in 2 cases (reconfection of the colostomy) a peristomal abscess in 2 cases (reconfection of the colostomy: 1 case, restoration of digestive continuity: 1 case) and a strangulated parastomal hernia in 1 case (herniorrhaphy). The elective incision and the perineal disease were risk factors for the occurrence of prolapse stomial. Surgical complications of colostomies remain a rare event. Prolapse is the most common complication, and it is mainly related to elective approach. Reoperation is often required especially in cases of early complications, with usually uneventful postoperative course.

  2. Membranous Septal Aneurysm: An Unusual Case for Sub-Pulmonary Obstruction in cTGA

    Directory of Open Access Journals (Sweden)

    Onur Isik

    2013-10-01

    Full Text Available Aneurysm of the membranous portion of the interventricular septum is an uncommon congenital cardiac malformation that is rarely diagnosed during life. Perimembranous ventricular septal defects are the most common type of the ventricular septal defects and originates from morphologically membranous interventricular septum. Surgical exposure and accurate closure of a ventricular septal defect with a membranous septal aneurysm beneath the tricuspid septal leaflet carries a risk of tricuspid valve insufficiency and conduction disturbances. The current study presents a case with membranous septal aneursym with congenitally corrected transposition of the great arteries and sub-pulmonary obstruction, which was surgically corrected.

  3. [da Vinci surgical system].

    Science.gov (United States)

    Watanabe, Gou; Ishikawa, Norihiro

    2014-07-01

    The da Vinci surgical system was developed by Intuitive Surgical Inc. in the United States as an endoscopic surgical device to assist remote control surgeries. In 1998, the Da Vinci system was first used for cardiothoracic procedures. Currently a combination of robot-assisted internal thoracic artery harvest together with coronary artery bypass grafting (CABG) through a mini-incision (ThoraCAB) or totally endoscopic procedures including anastomoses under robotic assistance (TECAB) are being conducted for the treatment of coronary artery diseases. With the recent advances in catheter interventions, hybrid procedures combining catheter intervention with ThoraCAB or TECAB are anticipated in the future.On the other hand, with the decrease in number of coronary artery bypass surgeries, the share of valvular surgeries is expected to increase in the future. Among them, mitral valvuloplasty for mitral regurgitation is anticipated to be conducted mainly by low-invasive procedures, represented by minimally invasive cardiac surgery( MICS) and robot-assisted surgery. Apart from the intrinsic good surgical view, robotic-assisted systems offer additional advantages of the availability of an amplified view and the easy to observe the mitral valve in the physiological position. Thus, robotic surgical surgeries that make complicated procedures easier are expected to accomplish further developments in the future. Furthermore, while the number of surgeries for atrial septal defects has decreased dramatically following the widespread use of Amplatzer septal occluder, robotic surgery may become a good indication for cases in which the Amplatzer device is not indicated. In Japan, clinical trial of the da Vinci robotic system for heart surgeries has been completed. Statutory approval of the da Vinci system for mitral regurgitation and atrial septal defects is anticipated in the next few years.

  4. Magnetically controlled permeability membranes

    KAUST Repository

    Kosel, Jurgen

    2013-10-31

    A bioactive material delivery system can include a thermoresponsive polymer membrane and nanowires distributed within the thermoresponsive polymer membrane. Magnetic activation of a thermoresponsive polymer membrane can take place via altering the magnetization or dimensions of nanowires dispersed or ordered within the membrane matrix.

  5. Magnetically controlled permeability membranes

    KAUST Repository

    Kosel, Jü rgen; Khashab, Niveen M.; Zaher, Amir

    2013-01-01

    A bioactive material delivery system can include a thermoresponsive polymer membrane and nanowires distributed within the thermoresponsive polymer membrane. Magnetic activation of a thermoresponsive polymer membrane can take place via altering the magnetization or dimensions of nanowires dispersed or ordered within the membrane matrix.

  6. Paediatric Abdominal Surgical Emergencies in a General Surgical ...

    African Journals Online (AJOL)

    ... organized for general surgeons undertaking paediatric surgical emergencies. More paediatric surgeons should be trained and more paediatric surgical units should established in the country. Key Words: Paediatric Abdominal Surgical Emergencies; Paediatric Surgeons, General Surgeons. Journal of College of Medicine ...

  7. Surgical camps: the Ugandan experience

    African Journals Online (AJOL)

    . The planned visits were advertised locally and in the national media. Screening of the patients was done first by the local medical teams and later by the visiting surgical teams. The surgical teams were comprised of the following personnel:.

  8. Improving surgical weekend handover

    OpenAIRE

    Culwick, Caroline; Devine, Chris; Coombs, Catherine

    2014-01-01

    Effective handovers are vital to patient safety and continuity of care, and this is recognised by several national bodies including the GMC. The existing model at Great Western Hospital (GWH) involved three general surgical teams and a urology team placing their printed patient lists, complete with weekend jobs, in a folder for the on-call team to collect at the weekend. We recognised a need to reduce time searching for patients, jobs and reviews, and to streamline weekend ward rounds. A unif...

  9. Acquiring minimally invasive surgical skills

    OpenAIRE

    Hiemstra, Ellen

    2012-01-01

    Many topics in surgical skills education have been implemented without a solid scientific basis. For that reason we have tried to find this scientific basis. We have focused on training and evaluation of minimally invasive surgical skills in a training setting and in practice in the operating room. This thesis has led to an enlarged insight in the organization of surgical skills training during residency training of surgical medical specialists.

  10. Robotic surgical training.

    Science.gov (United States)

    Ben-Or, Sharon; Nifong, L Wiley; Chitwood, W Randolph

    2013-01-01

    In July 2000, the da Vinci Surgical System (Intuitive Surgical, Inc) received Food and Drug Administration approval for intracardiac applications, and the first mitral valve repair was done at the East Carolina Heart Institute in May 2000. The system is now approved and used in many surgical specialties. With this disruptive technology and accepted use, surgeons and hospitals are seeking the most efficacious training pathway leading to safe use and responsible credentialing.One of the most important issues related to safe use is assembling the appropriate team of professionals involved with patient care. Moreover, proper patient selection and setting obtainable goals are also important.Creation and maintenance of a successful program are discussed in the article focusing on realistic goals. This begins with a partnership between surgeon leaders, hospital administrators, and industry support. Through this partnership, an appropriate training pathway and clinical pathway for success can be outlined. A timeline can then be created with periods of data analysis and adjustments as necessary. A successful program is attainable by following this pathway and attending to every detail along the journey.

  11. Surgical experts: born or made?

    Science.gov (United States)

    Sadideen, Hazim; Alvand, Abtin; Saadeddin, Munir; Kneebone, Roger

    2013-01-01

    The concept of surgical expertise and the processes involved in its development are topical, and there is a constant drive to identify reliable measures of expert performance in surgery. This review explores the notion of whether surgical experts are "born" or "made", with reference to educational theory and pertinent literature. Peer-reviewed publications, books, and online resources on surgical education, expertise and training were reviewed. Important themes and aspects of expertise acquisition were identified in order to better understand the concept of a surgical expert. The definition of surgical expertise and several important aspects of its development are highlighted. Innate talent plays an important role, but is insufficient on its own to produce a surgical expert. Multiple theories that explore motor skill acquisition and memory are relevant, and Ericsson's theory of the development of competence followed by deliberate self-practice has been especially influential. Psychomotor and non-technical skills are necessary for progression in the current climate in light of our training curricula; surgical experts are adaptive experts who excel in these. The literature suggests that surgical expertise is reached through practice; surgical experts are made, not born. A deeper understanding of the nature of expert performance and its development will ensure that surgical education training programmes are of the highest possible quality. Surgical educators should aim to develop an expertise-based approach, with expert performance as the benchmark. Copyright © 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

  12. Surgical navigation with QR codes

    Directory of Open Access Journals (Sweden)

    Katanacho Manuel

    2016-09-01

    Full Text Available The presented work is an alternative to established measurement systems in surgical navigation. The system is based on camera based tracking of QR code markers. The application uses a single video camera, integrated in a surgical lamp, that captures the QR markers attached to surgical instruments and to the patient.

  13. Nigerian Journal of Surgical Research

    African Journals Online (AJOL)

    The Nigerian Journal of Surgical Research is a publication of the Surgical Research Society with main office in Zaria, Nigeria. Zaria is home to Ahmadu Bello University (ABU), a premier university in Nigeria. The aim of The Nigerian Journal of Surgical Research is to cover developments and advances in the broad field of ...

  14. Surgical induction of choroidal neovascularization in a porcine model

    DEFF Research Database (Denmark)

    Lassota, Nathan; Kiilgaard, Jens Folke; Prause, Jan Ulrik

    2007-01-01

    PURPOSE: To develop a reproducible surgical technique for the induction of choroidal neovascularization (CNV) in the subretinal space of porcine eyes and to analyse the resulting CNV clinically and histologically. METHODS: Two different modifications of a surgical technique previously described...... were compared with the original method. In ten porcine eyes retinal pigment epithelial (RPE) cells were removed using a silicone tipped cannula, in ten porcine eyes Bruch's membrane was perforated once with a retinal perforator without prior RPE removal and in ten eyes RPE removal was followed...... by a single perforation of Bruch's membrane. Fifteen of the eyes, five from each group, were enucleated 30 minutes after surgery, while the remaining eyes were enucleated after 14 days. Prior to enucleation, at day 14, fundus photographs and fluorescein angiograms were obtained. Eyes were examined by light...

  15. Surgical management of hyperthyroidism.

    Science.gov (United States)

    Quérat, C; Germain, N; Dumollard, J-M; Estour, B; Peoc'h, M; Prades, J-M

    2015-04-01

    Hyperthyroidism includes several clinical and histopathological situations. Surgery is commonly indicated after failure of medical treatment. The aim of this study was to analyze the indications and complications of surgery as well as endocrine results. Patients operated on for hyperthyroidism between 2004 and 2012 were included in a retrospective study. Total thyroidectomy was performed for Graves' disease, toxic multinodular goiter and amiodarone-associated thyrotoxicosis; patients with toxic nodule underwent hemithyroidectomy. Pathologic analysis assessed surgical specimens; postoperative complications and resolution of hyperthyroidism were noted. Two hundred patients from 15 to 83 years old were included. One hundred and eighty-eight underwent primary surgery and 12 were re-operated for recurrent goiter (6 with subtotal thyroidectomy for multinodular goiter 25 years previously; 6 with hemithyroidectomy for solitary nodule 15 years previously). Eighty-two patients suffered from toxic multinodular goiter, 78 from Graves' disease, 35 from solitary toxic nodules and 5 from amiodarone-associated thyrotoxicosis. Fourteen papillary carcinomas (including 11 papillary microcarcinomas) and 34 healthy parathyroid glands (17%) were identified in the pathological specimens. Postoperative complications comprised 4% permanent recurrent laryngeal nerve palsy (1 year follow-up), 9% hematoma requiring surgical revision, and 3% definitive hypocalcemia. Normalization of thyroid hormone levels was observed in 198 patients. Two recurrences occurred due to incomplete resection (1 case of Graves' disease and 1 intrathoracic toxic goiter that occurred respectively 18 and 5 months after resection). Postoperative complications were more frequent in multinodular goiter (23%) than in Graves' disease (13%) (ns: P>0.05). Surgical management of hyperthyroidism enables good endocrinal control if surgery is complete. Patients need to be fully informed of all possible postoperative complications

  16. [Duane vertical surgical treatment].

    Science.gov (United States)

    Merino, M L; Gómez de Liaño, P; Merino, P; Franco, G

    2014-04-01

    We report 3 cases with a vertical incomitance in upgaze, narrowing of palpebral fissure, and pseudo-overaction of both inferior oblique muscles. Surgery consisted of an elevation of both lateral rectus muscles with an asymmetrical weakening. A satisfactory result was achieved in 2 cases, whereas a Lambda syndrome appeared in the other case. The surgical technique of upper-insertion with a recession of both lateral rectus muscles improved vertical incomitance in 2 of the 3 patients; however, a residual deviation remains in the majority of cases. Copyright © 2011 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  17. Hybrid adsorptive membrane reactor

    Science.gov (United States)

    Tsotsis, Theodore T [Huntington Beach, CA; Sahimi, Muhammad [Altadena, CA; Fayyaz-Najafi, Babak [Richmond, CA; Harale, Aadesh [Los Angeles, CA; Park, Byoung-Gi [Yeosu, KR; Liu, Paul K. T. [Lafayette Hill, PA

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  18. Premature rupture of membranes

    Science.gov (United States)

    ... gov/ency/patientinstructions/000512.htm Premature rupture of membranes To use the sharing features on this page, ... water that surrounds your baby in the womb. Membranes or layers of tissue hold in this fluid. ...

  19. Oxygen transport membrane

    DEFF Research Database (Denmark)

    2015-01-01

    The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof.......The present invention relates to a novel composite oxygen transport membrane as well as its preparation and uses thereof....

  20. Membrane with integrated spacer

    NARCIS (Netherlands)

    Balster, J.H.; Stamatialis, Dimitrios; Wessling, Matthias

    2010-01-01

    Many membrane processes are severely influenced by concentration polarisation. Turbulence promoting spacers placed in between the membranes can reduce the diffusional resistance of concentration polarisation by inducing additional mixing. Electrodialysis (ED) used for desalination suffers from

  1. Gel layer formation on membranes in Membrane Bioreactors

    NARCIS (Netherlands)

    Van den Brink, P.F.H.

    2014-01-01

    The widespread application of membrane bioreactors (MBRs) for municipal wastewater treatment is hampered by membrane fouling. Fouling increases energy demand, reduces process performance and creates the need for more frequent (chemical) membrane cleaning or replacement. Membrane fouling in MBRs is

  2. Smart membranes for monitoring membrane based desalination processes

    KAUST Repository

    Laleg-Kirati, Taous-Meriem; Karam, Ayman M.

    2017-01-01

    Various examples are related to smart membranes for monitoring membrane based process such as, e.g., membrane distillation processes. In one example, a membrane, includes a porous surface and a plurality of sensors (e.g., temperature, flow and

  3. Model cell membranes

    DEFF Research Database (Denmark)

    Günther-Pomorski, Thomas; Nylander, Tommy; Cardenas Gomez, Marite

    2014-01-01

    The high complexity of biological membranes has motivated the development and application of a wide range of model membrane systems to study biochemical and biophysical aspects of membranes in situ under well defined conditions. The aim is to provide fundamental understanding of processes control...

  4. Idiopathic epiretinal membrane

    NARCIS (Netherlands)

    Bu, Shao-Chong; Kuijer, Roelof; Li, Xiao-Rong; Hooymans, Johanna M M; Los, Leonoor I

    2014-01-01

    Background: Idiopathic epiretinal membrane (iERM) is a fibrocellular membrane that proliferates on the inner surface of the retina at the macular area. Membrane contraction is an important sight-threatening event and is due to fibrotic remodeling. Methods: Analysis of the current literature

  5. Meniscus Membranes For Separation

    Science.gov (United States)

    Dye, Robert C.; Jorgensen, Betty; Pesiri, David R.

    2005-09-20

    Gas separation membranes, especially meniscus-shaped membranes for gas separations are disclosed together with the use of such meniscus-shaped membranes for applications such as thermal gas valves, pre-concentration of a gas stream, and selective pre-screening of a gas stream. In addition, a rapid screening system for simultaneously screening polymer materials for effectiveness in gas separation is provided.

  6. Meniscus membranes for separations

    Science.gov (United States)

    Dye, Robert C [Irvine, CA; Jorgensen, Betty [Jemez Springs, NM; Pesiri, David R [Aliso Viejo, CA

    2004-01-27

    Gas separation membranes, especially meniscus-shaped membranes for gas separations are disclosed together with the use of such meniscus-shaped membranes for applications such as thermal gas valves, pre-concentration of a gas stream, and selective pre-screening of a gas stream. In addition, a rapid screening system for simultaneously screening polymer materials for effectiveness in gas separation is provided.

  7. [Surgical treatment of gynecomastia].

    Science.gov (United States)

    Târcoveanu, E; Lupaşcu, C; Vasilescu, A; Moldovanu, R; Ichim, Mihaela; Georgescu, St; Niculescu, D; Dănilă, N; Dimofte, G; Anton, Raluca; Crumpei, Felicia; Florea, Niculina; Ungureanu, Cristina

    2008-01-01

    Gynecomastia describes a benign increase of the mammary gland in men. When medical treatment fails, the surgical procedure is the treatment of choice. There are two main surgical procedures: subdermal mastectomy and liposuction. To evaluate the results after surgical treatment (mastectomy) performed in a general surgery unit. We performed a retrospective study; all the patients operated for gynecomastia were reviewed. The clinical, imaging, biological, intraoperative and histological data were included into a MS Access database and statistical analyzed. From 1990-2007, 114 patients were admitted in the First Surgical Clinic Iaşi for gynecomastia. Only 12.6% from the patients were with bilateral gynecomastia. The mean age was 40.54 +/- 1.83 years old (range 12-84). Mean body mass was 26.72 +/- 0.46 kg/m2 (range 18.5-41), and about 20% from the patients had a BMI of over 30 kg/m2. We also noted that 46.5% were smokers. Simon classification was used for preoperative staging: 2.6% from the cases (N = 3) were included in stage I, 16.7% (N = 19) in stage IIa, 50% (N = 57) in stage IIb and 30.7% in stage III. The patients included in stages IIa and I are younger then the patients included in stage III (p = 0.024). Mastodynia was noted in 46 cases (40.4%). Ultrasound exam was performed in all the cases, and the larger diameter of the nodule measured was 3.75 +/- 0.18 cm (range 0.5-9.7). Only three cases were preoperatively treated with tamoxifen. Most of the cases were operated using general anesthesia (53.5%). Mastectomy was performed by peri-areolar (70.2%), elliptical (28.9%) or radial (0.9%) incisions. The subdermal mastectomy using peri-areolar approach was performed especially for the cases included in stages I, IIa and IIb--p gynecomastia in 6 cases; the other cases presented dilated ducts. We also noted intraductal papillary hyperplasia in 87 cases and chronic inflammation in 35 cases. The histological exam also revealed intraductal papilloma--9 cases, fibro

  8. Surgical Instrument Sets for Special Operations Expeditionary Surgical Teams.

    Science.gov (United States)

    Hale, Diane F; Sexton, Justin C; Benavides, Linda C; Benavides, Jerry M; Lundy, Jonathan B

    The deployment of surgical assets has been driven by mission demands throughout years of military operations in Iraq and Afghanistan. The transition to the highly expeditious Golden Hour Offset Surgical Transport Team (GHOST- T) now offers highly mobile surgical assets in nontraditional operating rooms; the content of the surgical instrument sets has also transformed to accommodate this change. The 102nd Forward Surgical Team (FST) was attached to Special Operations assigned to southern Afghanistan from June 2015 to March 2016. The focus was to decrease overall size and weight of FST instrument sets without decreasing surgical capability of the GHOST-T. Each instrument set was evaluated and modified to include essential instruments to perform damage control surgery. The overall number of main instrument sets was decreased from eight to four; simplified augmentation sets have been added, which expand the capabilities of any main set. The overall size was decreased by 40% and overall weight decreased by 58%. The cardiothoracic, thoracotomy, and emergency thoracotomy trays were condensed to thoracic set. The orthopedic and amputation sets were replaced with an augmentation set of a prepackaged orthopedic external fixator set). An augmentation set to the major or minor basic sets, specifically for vascular injuries, was created. Through the reorganization of conventional FST surgical instrument sets to maintain damage control capabilities and mobility, the 102nd GHOST-T reduced surgical equipment volume and weight, providing a lesson learned for future surgical teams operating in austere environments. 2017.

  9. Separation membrane development

    Energy Technology Data Exchange (ETDEWEB)

    Lee, M.W. [Savannah River Technology Center, Aiken, SC (United States)

    1998-08-01

    A ceramic membrane has been developed to separate hydrogen from other gases. The method used is a sol-gel process. A thin layer of dense ceramic material is coated on a coarse ceramic filter substrate. The pore size distribution in the thin layer is controlled by a densification of the coating materials by heat treatment. The membrane has been tested by permeation measurement of the hydrogen and other gases. Selectivity of the membrane has been achieved to separate hydrogen from carbon monoxide. The permeation rate of hydrogen through the ceramic membrane was about 20 times larger than Pd-Ag membrane.

  10. Ex vivo repair of renal artery aneurysm associated with surgical treatment of abdominal aortic aneurysm

    Directory of Open Access Journals (Sweden)

    Kostić Dušan M.

    2004-01-01

    shorter arteries was implanted into the long artery, and another one into PTFE graft. After 30 minutes of explanation, autotransplantation of the kidney into the right iliac fossa was performed. The right renal vein was implanted into the inferior vein cava, and PTFE graft into the right limb of Dacron graft. Immediately following the completion of both anastomoses, large volume of urine was evident. Finally, ureteneocystostomy was performed with previous insertion of double "J" catheter. In the immediate postoperative period, renal function was restored to normal, while postoperative angiography revealed all patent grafts. DISCUSSION The most common causes of renal artery aneurysms are arteriosclerosis, as in our case, and fibro-muscular dysplasia. Very often, renal artery aneurysms are asymptomatic and discovered only during angiography in patients with aneurysmal and occlusive aortic disease. Other cases include: arterial hypertension, groin pain and acute or chronic renal failure. Due to relatively small number of evaluated cases, the risk of aneurysmal rupture is not known. According to some authors, the overall rupture rate of renal artery aneurysm is 5%, however, the rupture risk becomes higher in young pregnant woman. Several standard surgical procedures are available for the repair of renal artery aneurysms. These include saphenous vein angioplasty, bypass grafting, as well as ex vivo reconstruction with reimplantation or autotransplantation. Furthermore, interventional embolization therapy, as well as endovascular treatment with ePTFE covered stent, or autologous vein-coverage stent graft, have been also reported to be successful. CONCLUSION The major indications for surgical treatment of renal artery aneurysms are to eliminate the source of thromboembolism which leads to fixed renal hypertension and kidney failure, as well as prevention of aneurysmal rupture.

  11. Microporous silica membranes

    DEFF Research Database (Denmark)

    Boffa, Vittorio; Yue, Yuanzheng

    2012-01-01

    Hydrothermal stability is a crucial factor for the application of microporous silica-based membranes in industrial processes. Indeed, it is well established that steam exposure may cause densification and defect formation in microporous silica membranes, which are detrimental to both membrane...... permeability and selectivity. Numerous previous studies show that microporous transition metal doped-silica membranes are hydrothermally more stable than pure silica membranes, but less permeable. Here we present a quantitative study on the impact of type and concentration of transition metal ions...... on the microporous structure, stability and permeability of amorphous silica-based membranes, providing information on how to design chemical compositions and synthetic paths for the fabrication of silica-based membranes with a well accessible and highly stabile microporous structure....

  12. Clustering on Membranes

    DEFF Research Database (Denmark)

    Johannes, Ludger; Pezeshkian, Weria; Ipsen, John H

    2018-01-01

    Clustering of extracellular ligands and proteins on the plasma membrane is required to perform specific cellular functions, such as signaling and endocytosis. Attractive forces that originate in perturbations of the membrane's physical properties contribute to this clustering, in addition to direct...... protein-protein interactions. However, these membrane-mediated forces have not all been equally considered, despite their importance. In this review, we describe how line tension, lipid depletion, and membrane curvature contribute to membrane-mediated clustering. Additional attractive forces that arise...... from protein-induced perturbation of a membrane's fluctuations are also described. This review aims to provide a survey of the current understanding of membrane-mediated clustering and how this supports precise biological functions....

  13. Global curriculum in surgical oncology.

    Science.gov (United States)

    Are, C; Berman, R S; Wyld, L; Cummings, C; Lecoq, C; Audisio, R A

    2016-06-01

    The significant global variations in surgical oncology training paradigms can have a detrimental effect on tackling the rising global cancer burden. While some variations in training are essential to account for the differences in types of cancer and biology, the fundamental principles of providing care to a cancer patient remain the same. The development of a global curriculum in surgical oncology with incorporated essential standards could be very useful in building an adequately trained surgical oncology workforce, which in turn could help in tackling the rising global cancer burden. The leaders of the Society of Surgical Oncology and European Society of Surgical Oncology convened a global curriculum committee to develop a global curriculum in surgical oncology. A global curriculum in surgical oncology was developed to incorporate the required domains considered to be essential in training a surgical oncologist. The curriculum was constructed in a modular fashion to permit flexibility to suit the needs of the different regions of the world. Similarly, recognizing the various sociocultural, financial and cultural influences across the world, the proposed curriculum is aspirational and not mandatory in intent. A global curriculum was developed which may be considered as a foundational scaffolding for training surgical oncologists worldwide. It is envisioned that this initial global curriculum will provide a flexible and modular scaffolding that can be tailored by individual countries or regions to train surgical oncologists in a way that is appropriate for practice in their local environment. Copyright © 2016 Society of Surgical Oncology, European Society of Surgical Oncology. Published by Elsevier Ltd.. All rights reserved.

  14. Application of dynamic membranes in anaerobic membranes in anaerobic membrane bioreactor systems

    NARCIS (Netherlands)

    Erşahin, M.E.

    2015-01-01

    Anaerobic membrane bioreactors (AnMBRs) physically ensure biomass retention by the application of a membrane filtration process. With growing application experiences from aerobic membrane bioreactors (MBRs), the combination of membrane and anaerobic processes has received much attention and become

  15. VEIL Surgical Steps.

    Science.gov (United States)

    Raghunath, S K; Nagaraja, H; Srivatsa, N

    2017-03-01

    Inguinal lymphadenectomy remains the standard of care for metastatic nodal disease in cases of penile, urethral, vulval and vaginal cancers. Outcomes, including cure rates and overall and progression-free survivals, have progressively improved in these diseases with extending criteria to offer inguinal lymph node dissection for patients 'at-risk' for metastasis or loco-regional recurrence. Hence, despite declining incidence of advanced stages of these cancers, many patients will still need to undergo lymphadenectomy for optimal oncological outcomes. Inguinal node dissection is a morbid procedure with operative morbidity noted in almost two third of the patients. Video endoscopic inguinal lymphadenectomy (VEIL) was described and currently practiced with proven equivalent oncological outcomes. We describe our technique of VEIL using laparoscopic and robotic access as well as various new surgical strategies.

  16. Aggressive surgical management of craniopharyngiomas

    Directory of Open Access Journals (Sweden)

    Manmohan Singh

    2013-01-01

    Full Text Available Surgical treatment of craniopharyngiomas is challenging and despite advancements it continues to pose a challenge. Proponents of subtotal resection in conjunction with radiotherapy argue that this less aggressive approach can yield appropriate results with the lower morbidity. On the contrary, other argument is that gross total resection is superior. Though surgical management of craniopharyngioma is challenging due to its location and important surrounding neurovascular structures, optimal surgical results can be expected following radical surgical excision. Radical excision of craniopharyngiomas is associated with excellent long-term recurrence free survival. Radiation induced long-term complications can be altogether avoided by excising these tumors completely.

  17. Surgical treatment of parastomal hernia

    International Nuclear Information System (INIS)

    Basti, Z.; Mayer, A.

    2013-01-01

    Stoma construction is among standard surgical skills and is performed for many indications. Every stoma means huge impact on quality of life for patients even with great improvement in surgical technique and ostomy devices. All patients are very sensitive to complication of stoma and the most frequent complication is parastomal hernia. Incidence reported in literature is very high and unacceptable, it is 30-70%. Surgical approach is very demanding on technical equipment and experiences of surgeon. Authors focus on each surgical approach for treating this complication weather it´s using mesh or laparoscopic or open approach. (author)

  18. Probing lipid membrane electrostatics

    Science.gov (United States)

    Yang, Yi

    The electrostatic properties of lipid bilayer membranes play a significant role in many biological processes. Atomic force microscopy (AFM) is highly sensitive to membrane surface potential in electrolyte solutions. With fully characterized probe tips, AFM can perform quantitative electrostatic analysis of lipid membranes. Electrostatic interactions between Silicon nitride probes and supported zwitterionic dioleoylphosphatidylcholine (DOPC) bilayer with a variable fraction of anionic dioleoylphosphatidylserine (DOPS) were measured by AFM. Classical Gouy-Chapman theory was used to model the membrane electrostatics. The nonlinear Poisson-Boltzmann equation was numerically solved with finite element method to provide the potential distribution around the AFM tips. Theoretical tip-sample electrostatic interactions were calculated with the surface integral of both Maxwell and osmotic stress tensors on tip surface. The measured forces were interpreted with theoretical forces and the resulting surface charge densities of the membrane surfaces were in quantitative agreement with the Gouy-Chapman-Stern model of membrane charge regulation. It was demonstrated that the AFM can quantitatively detect membrane surface potential at a separation of several screening lengths, and that the AFM probe only perturbs the membrane surface potential by external field created by the internai membrane dipole moment. The analysis yields a dipole moment of 1.5 Debye per lipid with a dipole potential of +275 mV for supported DOPC membranes. This new ability to quantitatively measure the membrane dipole density in a noninvasive manner will be useful in identifying the biological effects of the dipole potential. Finally, heterogeneous model membranes were studied with fluid electric force microscopy (FEFM). Electrostatic mapping was demonstrated with 50 nm resolution. The capabilities of quantitative electrostatic measurement and lateral charge density mapping make AFM a unique and powerful

  19. Emulsification using microporous membranes

    Directory of Open Access Journals (Sweden)

    Goran T. Vladisavljević

    2011-10-01

    Full Text Available Membrane emulsification is a process of injecting a pure dispersed phase or pre-emulsion through a microporous membrane into the continuous phase. As a result of the immiscibility of the two phases, droplets of the dispersed phase are formed at the outlets of membrane pores. The droplets formed in the process are removed from the membrane surface by applying cross-flow or stirring of the continuous phase or using a dynamic (rotating or vibrating membrane. The most commonly used membrane for emulsification is the Shirasu Porous Glass (SPG membrane, fabricated through spinodal decomposition in a melt consisting of Japanese volcanic ash (Shirasu, boric acid and calcium carbonate. Microsieve membranes are increasingly popular as an alternative to highly tortuous glass and ceramic membranes. Microsieves are usually fabricated from nickel by photolithography and electroplating or they can be manufactured from silicon nitride via Reactive Ion Etching (RIE. An advantage of microsieves compared to the SPG membrane is in much higher transmembrane fluxes and higher tolerance to fouling by the emulsion ingredients due to the existence of short, straight through pores. Unlike conventional emulsification devices such as high-pressure valve homogenisers and rotor-stator devices, membrane emulsification devices permit a precise control over the mean pore size over a wide range and during the process insignificant amount of energy is dissipated as heat. The drop size is primarily determined by the pore size, but it depends also on other parameters, such as membrane wettability, emulsion formulation, shear stress on the membrane surface, transmembrane pressure, etc.

  20. Differences in collagen distribution of healthy and regenerated periodontium. Histomorphometric study in dogs.

    Science.gov (United States)

    Souza, Sérgio L S; Macedo, Guilherme O; Silveira E Souza, Adriana M M; Taba, Mário; Novaes, Arthur B; Oliver, Constance; Jamur, Maria C; Correa, Vani M A

    2013-10-01

    Previous studies have shown that there is a relationship between periodontal disease and the distribution of collagen fibers. This study evaluated the distribution of collagen types I and III in regenerated bone and periodontal ligament, comparing them to the tissues near the regenerated area and to the healthy periodontium. In the third (P3) and fourth (P4) mandibular premolars of 5 healthy mongrel dogs, bilaterally, buccal class 2 furcation lesions were surgically created and chronified for 3 weeks. After that, full flaps were elevated and expanded polytetrafluoroethylene (e-PTFE) membranes were adapted, sutured and recovered by the flaps. Two weeks after surgery, two membranes on the same side were removed and the other membranes were removed four weeks after surgery. The dogs were euthanized at 12 weeks following placement of the e-PTFE membranes. P3 and P4 teeth as well as the second premolars (healthy control teeth) and their periodontal tissues were removed and histologically processed for Collagen Quantification (COLQ). The amount of type III collagen was higher in native bone compared to the regenerated area. For periodontal ligament, COLQ for type I collagen showed statistically significant differences (Tukeys's Multiple Comparison, p⟨0.05) between the regenerated groups and the control group. These differences were not found for type III COLQ. There are significant differences in collagen distribution among the regenerated, native and control tissues. Membrane removal 2 or 4 weeks postoperatively did not influence the collagen composition.

  1. Access to Specialized Surgical Care

    African Journals Online (AJOL)

    The ANNALS of AFRICAN SURGERY. January 2016 Volume 13 Issue 1 1. EDITORIAL. Access to Specialized Surgical Care. Saidi H. University of Nairobi. Correspondence to: Prof Hassan Saidi, P.O Box 30196-00100, Nairobi. Email: hsaid2ke@yahoo.com. Ann Afr Surg. 2016;13(1):1-2. The narrative of surgical disease in ...

  2. Surgical residency: A tenant's view

    African Journals Online (AJOL)

    'To sleep: perchance to dream', is the frequent mantra of the surgical resident. However, unlike. Hamlet, there is no ensuing speculation as to what dreams may come as there are seldom any!! Surgical residency has been both vilified and immortalized, but the fact remains that it is one of the most challenging, provocative ...

  3. Surgical innovations in canine gonadectomy

    NARCIS (Netherlands)

    Van Goethem, Bart

    2016-01-01

    In this thesis some recent technological developments in human surgery are evaluated for their potential use in veterinary medicine by introducing them as surgical innovations for canine gonadectomy. Barbed sutures achieve wound apposition without surgical knot tying and thus avoid knot-associated

  4. Acquiring minimally invasive surgical skills

    NARCIS (Netherlands)

    Hiemstra, Ellen

    2012-01-01

    Many topics in surgical skills education have been implemented without a solid scientific basis. For that reason we have tried to find this scientific basis. We have focused on training and evaluation of minimally invasive surgical skills in a training setting and in practice in the operating room.

  5. Ion-conducting membranes

    Science.gov (United States)

    Masel, Richard I.; Sajjad, Syed Dawar; Gao, Yan; Liu, Zengcai; Chen, Qingmei

    2017-12-26

    An anion-conducting polymeric membrane comprises a terpolymer of styrene, vinylbenzyl-R.sub.s and vinylbenzyl-R.sub.x. R.sub.s is a positively charged cyclic amine group. R.sub.x is at least one constituent selected from the group consisting Cl, OH and a reaction product between an OH or Cl and a species other than a simple amine or a cyclic amine. The total weight of the vinylbenzyl-R.sub.x groups is greater than 0.3% of the total weight of the membrane. In a preferred embodiment, the membrane is a Helper Membrane that increases the faradaic efficiency of an electrochemical cell into which the membrane is incorporated, and also allows product formation at lower voltages than in cells without the Helper Membrane.

  6. Gas separation with membranes

    International Nuclear Information System (INIS)

    Schulz, G.; Michele, H.; Werner, U.

    1982-01-01

    Gas separation with membranes has already been tested in numerous fields of application, e.g. uranium enrichment of H 2 separation. In many of these processes the mass transfer units, so-called permeators, have to be connected in tandem in order to achieve high concentrations. A most economical operating method provides for each case an optimization of the cascades with regard to the membrane materials, construction and design of module. By utilization of the concentration gradient along the membrane a new process development has been accomplished - the continuously operating membrane rectification unit. Investment and operating costs can be reduced considerably for a number of separating processes by combining a membrane rectification unit with a conventional recycling cascade. However, the new procedure requires that the specifications for the module construction, flow design, and membrane properties be reconsidered. (orig.) [de

  7. Combined Surgical Treatment of Gynecomastia

    Directory of Open Access Journals (Sweden)

    Yordanov Y.

    2015-05-01

    Full Text Available Surgical treatment of gynecomastia could present unique challenges for the plastic surgeon. Achieving a good balance between effectiveness of the selected approach and the satisfactory aesthetic outcome often is a difficult endeavor. Optimal surgical treatment involves a combination of liposuction and direct excision. In the present study the charts of 11 patients treated with suction-assisted liposuction and direct surgical excision were retrospectively reviewed; a special emphasis is placed on the surgical technique. The mean follow-up period of the patients was 11.6 months. No infection, hematoma, nipple-areola complex necrosis and nipple retraction was encountered in this series. The combined surgical treatment of gynecomastia has shown to be a reliable technique in both small and moderate breast enlargement including those with skin excess.

  8. Chelating polymeric membranes

    KAUST Repository

    Peinemann, Klaus-Viktor

    2015-01-22

    The present application offers a solution to the current problems associated with recovery and recycling of precious metals from scrap material, discard articles, and other items comprising one or more precious metals. The solution is premised on a microporous chelating polymeric membrane. Embodiments include, but are not limited to, microporous chelating polymeric membranes, device comprising the membranes, and methods of using and making the same.

  9. Output control of da Vinci surgical system's surgical graspers.

    Science.gov (United States)

    Johnson, Paul J; Schmidt, David E; Duvvuri, Umamaheswar

    2014-01-01

    The number of robot-assisted surgeries performed with the da Vinci surgical system has increased significantly over the past decade. The articulating movements of the robotic surgical grasper are controlled by grip controls at the master console. The user interface has been implicated as one contributing factor in surgical grasping errors. The goal of our study was to characterize and evaluate the user interface of the da Vinci surgical system in controlling surgical graspers. An angular manipulator with force sensors was used to increment the grip control angle as grasper output angles were measured. Input force at the grip control was simultaneously measured throughout the range of motion. Pressure film was used to assess the maximum grasping force achievable with the endoscopic grasping tool. The da Vinci robot's grip control angular input has a nonproportional relationship with the grasper instrument output. The grip control mechanism presents an intrinsic resistant force to the surgeon's fingertips and provides no haptic feedback. The da Vinci Maryland graspers are capable of applying up to 5.1 MPa of local pressure. The angular and force input at the grip control of the da Vinci robot's surgical graspers is nonproportional to the grasper instrument's output. Understanding the true relationship of the grip control input to grasper instrument output may help surgeons understand how to better control the surgical graspers and promote fewer grasping errors. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Gas separation membranes

    Science.gov (United States)

    Schell, William J.

    1979-01-01

    A dry, fabric supported, polymeric gas separation membrane, such as cellulose acetate, is prepared by casting a solution of the polymer onto a shrinkable fabric preferably formed of synthetic polymers such as polyester or polyamide filaments before washing, stretching or calendering (so called griege goods). The supported membrane is then subjected to gelling, annealing, and drying by solvent exchange. During the processing steps, both the fabric support and the membrane shrink a preselected, controlled amount which prevents curling, wrinkling or cracking of the membrane in flat form or when spirally wound into a gas separation element.

  11. Anion exchange membrane

    Science.gov (United States)

    Verkade, John G; Wadhwa, Kuldeep; Kong, Xueqian; Schmidt-Rohr, Klaus

    2013-05-07

    An anion exchange membrane and fuel cell incorporating the anion exchange membrane are detailed in which proazaphosphatrane and azaphosphatrane cations are covalently bonded to a sulfonated fluoropolymer support along with anionic counterions. A positive charge is dispersed in the aforementioned cations which are buried in the support to reduce the cation-anion interactions and increase the mobility of hydroxide ions, for example, across the membrane. The anion exchange membrane has the ability to operate at high temperatures and in highly alkaline environments with high conductivity and low resistance.

  12. Photoresponsive nanostructured membranes

    KAUST Repository

    Madhavan, Poornima

    2016-07-26

    The perspective of adding stimuli-response to isoporous membranes stimulates the development of separation devices with pores, which would open or close under control of environment chemical composition, temperature or exposure to light. Changes in pH and temperature have been previously investigated. In this work, we demonstrate for the first time the preparation of photoresponsive isoporous membranes, applying self-assembly non-solvent induced phase separation to a new light responsive block copolymer. First, we optimized the membrane formation by using poly(styrene-b-anthracene methyl methacrylate-b-methylmethacrylate) (PS-b-PAnMMA-b-PMMA) copolymer, identifying the most suitable solvent, copolymer block length, and other parameters. The obtained final triblock copolymer membrane morphologies were characterized using atomic force and electron microscopy. The microscopic analysis reveals that the PS-b-PAnMMA-b-PMMA copolymer can form both lamellar and ordered hexagonal nanoporous structures on the membrane top layer in appropriate solvent compositions. The nanostructured membrane emits fluorescence due to the presence of the anthracene mid-block. On irradiation of light the PS-b-PAnMMA-b-PMMA copolymer membranes has an additional stimuli response. The anthracene group undergoes conformational changes by forming [4 + 4] cycloadducts and this alters the membrane\\'s water flux and solute retention. © 2016 The Royal Society of Chemistry.

  13. Membrane fusion and exocytosis.

    Science.gov (United States)

    Jahn, R; Südhof, T C

    1999-01-01

    Membrane fusion involves the merger of two phospholipid bilayers in an aqueous environment. In artificial lipid bilayers, fusion proceeds by means of defined transition states, including hourglass-shaped intermediates in which the proximal leaflets of the fusing membranes are merged whereas the distal leaflets are separate (fusion stalk), followed by the reversible opening of small aqueous fusion pores. Fusion of biological membranes requires the action of specific fusion proteins. Best understood are the viral fusion proteins that are responsible for merging the viral with the host cell membrane during infection. These proteins undergo spontaneous and dramatic conformational changes upon activation. In the case of the paradigmatic fusion proteins of the influenza virus and of the human immunodeficiency virus, an amphiphilic fusion peptide is inserted into the target membrane. The protein then reorients itself, thus forcing the fusing membranes together and inducing lipid mixing. Fusion of intracellular membranes in eukaryotic cells involves several protein families including SNAREs, Rab proteins, and Sec1/Munc-18 related proteins (SM-proteins). SNAREs form a novel superfamily of small and mostly membrane-anchored proteins that share a common motif of about 60 amino acids (SNARE motif). SNAREs reversibly assemble into tightly packed helical bundles, the core complexes. Assembly is thought to pull the fusing membranes closely together, thus inducing fusion. SM-proteins comprise a family of soluble proteins that bind to certain types of SNAREs and prevent the formation of core complexes. Rab proteins are GTPases that undergo highly regulated GTP-GDP cycles. In their GTP form, they interact with specific proteins, the effector proteins. Recent evidence suggests that Rab proteins function in the initial membrane contact connecting the fusing membranes but are not involved in the fusion reaction itself.

  14. Surgical therapy in chronic pancreatitis.

    Science.gov (United States)

    Neal, C P; Dennison, A R; Garcea, G

    2012-12-01

    Chronic pancreatitis (CP) is an inflammatory disease of the pancreas which causes chronic pain, as well as exocrine and endocrine failure in the majority of patients, together producing social and domestic upheaval and a very poor quality of life. At least half of patients will require surgical intervention at some stage in their disease, primarily for the treatment of persistent pain. Available data have now confirmed that surgical intervention may produce superior results to conservative and endoscopic treatment. Comprehensive individual patient assessment is crucial to optimal surgical management, however, in order to determine which morphological disease variant (large duct disease, distal stricture with focal disease, expanded head or small duct/minimal change disease) is present in the individual patient, as a wide and differing range of surgical approaches are possible depending upon the specific abnormality within the gland. This review comprehensively assesses the evidence for these differing approaches to surgical intervention in chronic pancreatitis. Surgical drainage procedures should be limited to a small number of patients with a dilated duct and no pancreatic head mass. Similarly, a small population presenting with a focal stricture and tail only disease may be successfully treated by distal pancreatectomy. Long-term results of both of these procedure types are poor, however. More impressive results have been yielded for the surgical treatment of the expanded head, for which a range of surgical options now exist. Evidence from level I studies and a recent meta-analysis suggests that duodenum-preserving resections offer benefits compared to pancreaticoduodenectomy, though the results of the ongoing, multicentre ChroPac trial are awaited to confirm this. Further data are also needed to determine which of the duodenum-preserving procedures provides optimal results. In relation to small duct/minimal change disease total pancreatectomy represents the only

  15. Surgical Skills Beyond Scientific Management.

    Science.gov (United States)

    Whitfield, Nicholas

    2015-07-01

    During the Great War, the French surgeon Alexis Carrel, in collaboration with the English chemist Henry Dakin, devised an antiseptic treatment for infected wounds. This paper focuses on Carrel's attempt to standardise knowledge of infected wounds and their treatment, and looks closely at the vision of surgical skill he espoused and its difference from those associated with the doctrines of scientific management. Examining contemporary claims that the Carrel-Dakin method increased rather than diminished demands on surgical work, this paper further shows how debates about antiseptic wound treatment opened up a critical space for considering the nature of skill as a vital dynamic in surgical innovation and practice.

  16. Plasma membrane ATPases

    DEFF Research Database (Denmark)

    Palmgren, Michael Broberg; Bækgaard, Lone; Lopez Marques, Rosa Laura

    2011-01-01

    The plasma membrane separates the cellular contents from the surrounding environment. Nutrients must enter through the plasma membrane in order to reach the cell interior, and toxic metabolites and several ions leave the cell by traveling across the same barrier. Biological pumps in the plasma me...

  17. Polymide gas separation membranes

    Science.gov (United States)

    Ding, Yong; Bikson, Benjamin; Nelson, Joyce Katz

    2004-09-14

    Soluble polyamic acid salt (PAAS) precursors comprised of tertiary and quaternary amines, ammonium cations, sulfonium cations, or phosphonium cations, are prepared and fabricated into membranes that are subsequently imidized and converted into rigid-rod polyimide articles, such as membranes with desirable gas separation properties. A method of enhancing solubility of PAAS polymers in alcohols is also disclosed.

  18. Enantioseparation with liquid membranes

    NARCIS (Netherlands)

    Gössi, Angelo; Riedl, Wolfgang; Schuur, Boelo

    Chiral resolution of racemic products is a challenging and important task in the pharmaceutical, agrochemical, flavor, polymer and fragrances industries. One of the options for these challenging separations is to use liquid membranes. Although liquid membranes have been known for almost four decades

  19. Silicon nitride nanosieve membrane

    NARCIS (Netherlands)

    Tong, D.H.; Jansen, Henricus V.; Gadgil, V.J.; Bostan, C.G.; Berenschot, Johan W.; van Rijn, C.J.M.; Elwenspoek, Michael Curt

    2004-01-01

    An array of very uniform cylindrical nanopores with a pore diameter as small as 25 nm has been fabricated in an ultrathin micromachined silicon nitride membrane using focused ion beam (FIB) etching. The pore size of this nanosieve membrane was further reduced to below 10 nm by coating it with

  20. Membrane capacitive deionization

    NARCIS (Netherlands)

    Biesheuvel, P.M.; Wal, van der A.

    2010-01-01

    Membrane capacitive deionization (MCDI) is an ion-removal process based on applying an electrical potential difference across an aqueous solution which flows in between oppositely placed porous electrodes, in front of which ion-exchange membranes are positioned. Due to the applied potential, ions

  1. Photoresponsive nanostructured membranes

    KAUST Repository

    Madhavan, Poornima; Sutisna, Burhannudin; Sougrat, Rachid; Nunes, Suzana Pereira

    2016-01-01

    The perspective of adding stimuli-response to isoporous membranes stimulates the development of separation devices with pores, which would open or close under control of environment chemical composition, temperature or exposure to light. Changes in pH and temperature have been previously investigated. In this work, we demonstrate for the first time the preparation of photoresponsive isoporous membranes, applying self-assembly non-solvent induced phase separation to a new light responsive block copolymer. First, we optimized the membrane formation by using poly(styrene-b-anthracene methyl methacrylate-b-methylmethacrylate) (PS-b-PAnMMA-b-PMMA) copolymer, identifying the most suitable solvent, copolymer block length, and other parameters. The obtained final triblock copolymer membrane morphologies were characterized using atomic force and electron microscopy. The microscopic analysis reveals that the PS-b-PAnMMA-b-PMMA copolymer can form both lamellar and ordered hexagonal nanoporous structures on the membrane top layer in appropriate solvent compositions. The nanostructured membrane emits fluorescence due to the presence of the anthracene mid-block. On irradiation of light the PS-b-PAnMMA-b-PMMA copolymer membranes has an additional stimuli response. The anthracene group undergoes conformational changes by forming [4 + 4] cycloadducts and this alters the membrane's water flux and solute retention. © 2016 The Royal Society of Chemistry.

  2. Surgical therapies for corneal perforations: 10 years of cases in a tertiary referral hospital

    Directory of Open Access Journals (Sweden)

    Yokogawa H

    2014-10-01

    Full Text Available Hideaki Yokogawa, Akira Kobayashi, Natsuko Yamazaki, Toshinori Masaki, Kazuhisa Sugiyama Department of Ophthalmology, Kanazawa University Graduate School of Medical Science, Kanazawa, JapanPurpose: To report surgical therapies for corneal perforations in a tertiary referral hospital.Methods: Thirty-one eyes of 31 patients (aged 62.4±18.3 years with surgically treated corneal perforations from January 2002 to July 2013 were included in this study. Demographic data such as cause of corneal perforation, surgical procedures, and visual outcomes were retrospectively analyzed.Results: The causes of corneal perforation (n=31 were divided into infectious (n=8, 26% and noninfectious (n=23, 74% categories. Infectious causes included fungal ulcer, herpetic stromal necrotizing keratitis, and bacterial ulcer. The causes of noninfectious keratopathy included corneal melting after removal of a metal foreign body, severe dry eye, lagophthalmos, canaliculitis, the oral anticancer drug S-1, keratoconus, rheumatoid arthritis, neurotrophic ulcer, atopic keratoconjunctivitis, and unknown causes. Initial surgical procedures included central large corneal graft (n=17, small corneal graft (n=7, and amniotic membrane transplantation (n=7. In two cases the perforation could not be sealed during the first surgical treatment and required subsequent procedures. All infectious keratitis required central large penetrating keratoplasty to obtain anatomical cure. In contrast, several surgical options were used for the treatment of noninfectious keratitis. After surgical treatment, anatomical cure was obtained in all cases. Mean postoperative best corrected visual acuity was better at 6 months (logMAR 1.3 than preoperatively (logMAR 1.8.Conclusion: Surgical therapies for corneal perforations in our hospital included central large lamellar/penetrating keratoplasty, small peripheral patch graft, and amniotic membrane transplantation. All treatments were effective. Corneal

  3. Molecular Interactions at Membranes

    DEFF Research Database (Denmark)

    Jagalski, Vivien

    . Today, we know more than ever before about the properties of biological membranes. Advanced biophysical techniques and sophisticated membrane models allow us to answer specific questions about the structure of the components within membranes and their interactions. However, many detailed structural...... the surface-immobilization of LeuT by exchanging the detergent with natural phosphatidylcholine (PC) lipids. Various surface sensitive techniques, including neutron reflectometry (NR), are employed and finally enabled us to confirm the gross structure of LeuT in a lipid environment as predicted by molecular...... dynamic simulations. In a second study, the co-localization of three toxic plant-derived diterpene resin acids (RAs) within DPPC membranes was investigated. These compounds are reported to disrupt the membrane and increase its fluidity. The RAs used in this study vary in their toxicity while...

  4. Membrane technology and applications

    International Nuclear Information System (INIS)

    Khalil, F.H.

    1997-01-01

    The main purpose of this dissertation is to prepare and characterize some synthetic membranes obtained by radiation-induced graft copolymerization of and A Am unitary and binary system onto nylon-6 films. The optimum conditions at which the grafting process proceeded homogeneously were determined. Some selected properties of the prepared membranes were studied. Differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), x-ray diffraction (XRD), mechanical properties and U.V./vis, instruments and techniques were used to characterize the prepared membranes. The use of such membranes for the decontamination of radioactive waste and some heavy metal ions as water pollutants were investigated. These grafted membranes showed good cation exchange properties and may be of practical interest in waste water treatment whether this water was radioactive or not. 4 tabs., 68 figs., 146 refs

  5. ANAESTHESIA FOR OPHTHALMIC SURGICAL PROCEDURES

    African Journals Online (AJOL)

    Objective: To review factors influencing the choice of anaesthesia for ophthalmic surgical procedures. ... as risk associated with general anaesthesia (8) they are more .... Wilson ME, Pandey SK, Thakur J. Paediatric cataract blindness in the ...

  6. uniportal vats for surgical repair

    African Journals Online (AJOL)

    2017-03-23

    Mar 23, 2017 ... aDepartamet of Pediatric Surgery, Hospital Teresa Herrera, Complejo Hospitalario. Universitario de A ... Advances in anesthesia, neonatal intensive, surgical, and cardiac care have ... First, these patients are at risk of airway ...

  7. Spinal surgery: non surgical complications

    African Journals Online (AJOL)

    Adele

    surgical procedure). Arterial cannulation ... Acute retinal necrosis syndrome after epidural corticos- teroid injections ... prevented, or respond to early recognition and treatment. ..... drugs should only be administered if there are no alternatives.

  8. Patient-specific surgical simulation.

    Science.gov (United States)

    Soler, Luc; Marescaux, Jacques

    2008-02-01

    Technological innovations of the twentieth century have provided medicine and surgery with new tools for education and therapy definition. Thus, by combining Medical Imaging and Virtual Reality, patient-specific applications providing preoperative surgical simulation have become possible.

  9. Surgical management of Crohn's disease.

    Science.gov (United States)

    Lu, Kim C; Hunt, Steven R

    2013-02-01

    Although medical management can control symptoms in a recurring incurable disease, such as Crohn's disease, surgical management is reserved for disease complications or those problems refractory to medical management. In this article, we cover general principles for the surgical management of Crohn's disease, ranging from skin tags, abscesses, fistulae, and stenoses to small bowel and extraintestinal disease. Copyright © 2013 Elsevier Inc. All rights reserved.

  10. Surgical innovations in canine gonadectomy

    OpenAIRE

    Van Goethem, Bart

    2016-01-01

    In this thesis some recent technological developments in human surgery are evaluated for their potential use in veterinary medicine by introducing them as surgical innovations for canine gonadectomy. Barbed sutures achieve wound apposition without surgical knot tying and thus avoid knot-associated negative consequences (lengthy placement, impaired wound healing around bulky knots, and the effect of unsightly knots on cosmetics). A study in 9 dogs found that celiotomy closure was easily achiev...

  11. Evolution of surgical skills training

    Science.gov (United States)

    Roberts, Kurt E; Bell, Robert L; Duffy, Andrew J

    2006-01-01

    Surgical training is changing: one hundred years of tradition is being challenged by legal and ethical concerns for patient safety, work hours restrictions, the cost of operating room time, and complications. Surgical simulation and skills training offers an opportunity to teach and practice advanced skills outside of the operating room environment before attempting them on living patients. Simulation training can be as straight forward as using real instruments and video equipment to manipulate simulated “tissue” in a box trainer. More advanced, virtual reality simulators are now available and ready for widespread use. Early systems have demonstrated their effectiveness and discriminative ability. Newer systems enable the development of comprehensive curricula and full procedural simulations. The Accreditation Council of Graduate Medical Education’s (ACGME) has mandated the development of novel methods of training and evaluation. Surgical organizations are calling for methods to ensure the maintenance of skills, advance surgical training, and to credential surgeons as technically competent. Simulators in their current form have been demonstrated to improve the operating room performance of surgical residents. Development of standardized training curricula remains an urgent and important agenda, particularly for minimal invasive surgery. An innovative and progressive approach, borrowing experiences from the field of aviation, can provide the foundation for the next century of surgical training, ensuring the quality of the product. As the technology develops, the way we practice will continue to evolve, to the benefit of physicians and patients. PMID:16718842

  12. Minimizing surgical skin incision scars with a latex surgical glove.

    Science.gov (United States)

    Han, So-Eun; Ryoo, Suk-Tae; Lim, So Young; Pyon, Jai-Kyung; Bang, Sa-Ik; Oh, Kap-Sung; Mun, Goo-Hyun

    2013-04-01

    The current trend in minimally invasive surgery is to make a small surgical incision. However, the excessive tensile stress applied by the retractors to the skin surrounding the incision often results in a long wound healing time and extensive scarring. To minimize these types of wound problems, the authors evaluated a simple and cost-effective method to minimize surgical incision scars based on the use of a latex surgical glove. The tunnel-shaped part of a powder-free latex surgical glove was applied to the incision and the dissection plane. It was fixed to the full layer of the dissection plane with sutures. The glove on the skin surface then was sealed with Ioban (3 M Health Care, St. Paul, MN, USA) to prevent movement. The operation proceeded as usual, with the retractor running through the tunnel of the latex glove. It was possible to complete the operation without any disturbance of the visual field by the surgical glove, and the glove was neither torn nor separated by the retractors. The retractors caused traction and friction during the operation, but the extent of damage to the postoperative skin incision margin was remarkably less than when the operation was performed without a glove. This simple and cost-effective method is based on the use of a latex surgical glove to protect the surgical skin incision site and improve the appearance of the postoperative scar. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  13. Bacterial migration through punctured surgical gloves under real surgical conditions

    Directory of Open Access Journals (Sweden)

    Heidecke Claus-Dieter

    2010-07-01

    Full Text Available Abstract Background The aim of this study was to confirm recent results from a previous study focussing on the development of a method to measure the bacterial translocation through puncture holes in surgical gloves under real surgical conditions. Methods An established method was applied to detect bacterial migration from the operating site through the punctured glove. Biogel™ double-gloving surgical gloves were used during visceral surgeries over a 6-month period. A modified Gaschen-bag method was used to retrieve organisms from the inner glove, and thus-obtained bacteria were compared with micro-organisms detected by an intra-operative swab. Results In 20 consecutive procedures, 194 gloves (98 outer gloves, 96 inner gloves were examined. The rate of micro-perforations of the outer surgical glove was 10% with a median wearing time of 100 minutes (range: 20-175 minutes. Perforations occurred in 81% on the non-dominant hand, with the index finger most frequently (25% punctured. In six cases, bacterial migration could be demonstrated microbiologically. In 5% (5/98 of outer gloves and in 1% (1/96 of the inner gloves, bacterial migration through micro-perforations was observed. For gloves with detected micro-perforations (n = 10 outer layers, the calculated migration was 50% (n = 5. The minimum wearing time was 62 minutes, with a calculated median wearing time of 71 minutes. Conclusions This study confirms previous results that bacterial migration through unnoticed micro-perforations in surgical gloves does occur under real practical surgical conditions. Undetected perforation of surgical gloves occurs frequently. Bacterial migration from the patient through micro-perforations on the hand of surgeons was confirmed, limiting the protective barrier function of gloves if worn over longer periods.

  14. Surgical management of fibrotic encapsulation of the fluocinolone acetonide implant in CAPN5-associated proliferative vitreoretinopathy.

    Science.gov (United States)

    Tlucek, Paul S; Folk, James C; Sobol, Warren M; Mahajan, Vinit B

    2013-01-01

    To review fibrosis of fluocinolone acetonide (FA) implants in subjects with CAPN5 autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV). A retrospective case series was assembled from ADNIV patients in which there was fibrotic encapsulation of a fluocinolone acetonide implant. CAPN5 genotypes and surgical repair techniques were reviewed. Two eyes of two ADNIV patients developed a fibrotic capsule over the fluocinolone acetonide implant. Both patients had Stage IV disease. Patient A had a c.731T > C mutation in the CAPN5 gene and patient B had a c.728G > T mutation. The fibrotic membrane was surgically excised and the implant function was restored. The exuberant fibrotic response in later stages of ADNIV may be resistant to local immunosuppression with steroids. Surgical excision of fibrotic membranes over FA implants can reestablish local steroid delivery in cases of severe proliferative vitreoretinopathy.

  15. Epiretinal membrane removal in patients with Stargardt disease

    Directory of Open Access Journals (Sweden)

    Muna Bhende

    2015-01-01

    Full Text Available Epiretinal membranes (ERMs in Stargardt disease have been known to undergo spontaneous separation in children. Results of surgical intervention in adult patients with Stargardt disease have rarely been reported. A retrospective review of results of surgical intervention for ERM causing visual impairment in two adult patients of Stargardt disease was carried out. Both patients developed ERM in one eye during their follow-up period with the resultant drop in their preexisting visual acuity. Postsurgery, restoration of foveal contour with some improvement in visual acuity was observed in both patients. No adverse effect of surgery was noted.

  16. Microfabricated hydrogen sensitive membranes

    Energy Technology Data Exchange (ETDEWEB)

    Naddaf, A.; Kraetz, L. [Lehrstuhl fuer Thermische Verfahrenstechnik, Technische Universitaet Kaiserslautern (Germany); Detemple, P.; Schmitt, S.; Hessel, V. [Institut fuer Mikrotechnik Mainz GmbH, Mainz (Germany); Faqir, N. [University of Jordan, Amman (Jordan); Bart, H.J.

    2009-01-15

    Thin, defect-free palladium, palladium/copper and palladium/silver hydrogen absorbing membranes were microfabricated. A dual sputtering technique was used to deposit the palladium alloy membranes of only 1 {mu}m thickness on a nonporous silicon substrate. Advanced silicon etching (ASE) was applied on the backside to create a mechanically stable support structure for the thin films. Performance evaluation was carried out for different gases in a temperature range of 20 C to 298 C at a constant differential pressure of 110 kPa at the two sides of the membrane. The composite membranes show an excellent permeation rate of hydrogen, which appears to be 0.05 Pa m{sup 3} s{sup -1} and 0.01.10{sup -3} Pa m{sup 3} s{sup -1} at 20 C for the microfabricated 23 % silver and the 53 % copper composite membranes, respectively. The selectivity to hydrogen over a gas mixture containing, in addition to hydrogen, carbon monoxide, carbon dioxide and nitrogen was measured. The mass spectrometer did not detect any CO{sub 2} or CO, showing that the membrane is completely hydrogen selective. The microfabricated membranes exhibit both high mechanical strength (they easily withstand pressures up to 4 bar) and high thermal stability (up to 650 C). (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  17. Catalytic nanoporous membranes

    Science.gov (United States)

    Pellin, Michael J; Hryn, John N; Elam, Jeffrey W

    2013-08-27

    A nanoporous catalytic membrane which displays several unique features Including pores which can go through the entire thickness of the membrane. The membrane has a higher catalytic and product selectivity than conventional catalysts. Anodic aluminum oxide (AAO) membranes serve as the catalyst substrate. This substrate is then subjected to Atomic Layer Deposition (ALD), which allows the controlled narrowing of the pores from 40 nm to 10 nm in the substrate by deposition of a preparatory material. Subsequent deposition of a catalytic layer on the inner surfaces of the pores reduces pore sizes to less than 10 nm and allows for a higher degree of reaction selectivity. The small pore sizes allow control over which molecules enter the pores, and the flow-through feature can allow for partial oxidation of reactant species as opposed to complete oxidation. A nanoporous separation membrane, produced by ALD is also provided for use in gaseous and liquid separations. The membrane has a high flow rate of material with 100% selectivity. Also provided is a method for producing a catalytic membrane having flow-through pores and discreet catalytic clusters adhering to the inside surfaces of the pores.

  18. Rotating bubble membrane radiator

    Science.gov (United States)

    Webb, Brent J.; Coomes, Edmund P.

    1988-12-06

    A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

  19. Imaging of Conductive Hearing Loss With a Normal Tympanic Membrane.

    Science.gov (United States)

    Curtin, Hugh D

    2016-01-01

    This article presents an approach to imaging conductive hearing loss in patients with normal tympanic membranes and discusses entities that should be checked as the radiologist evaluates this potentially complicated issue. Conductive hearing loss in a patient with a normal tympanic membrane is a complicated condition that requires a careful imaging approach. Imaging should focus on otosclerosis, and possible mimics and potential surgical considerations should be evaluated. The radiologist should examine the ossicular chain and the round window and keep in mind that a defect in the superior semicircular canal can disturb the hydraulic integrity of the labyrinth.

  20. Early surgical treatment of retinal hemangioblastomas.

    Science.gov (United States)

    van Overdam, Koen A; Missotten, Tom; Kilic, Emine; Spielberg, Leigh H

    2017-02-01

    To evaluate the clinical course after early surgical treatment with excision of retinal hemangioblastomas (RHs) before development of major complications. Interventional case series of four eyes (four patients) with a peripheral RH that had not yet been treated by laser or cryotherapy prior to surgery. All eyes underwent 23-gauge vitrectomy with lesion excision. One patient underwent ligation of the feeder vessel prior to lesion excision. Best-corrected visual acuity and clinical course were assessed during a follow-up period of at least 4 years. Four patients (mean age 27.3 years; range 19-32) were included, of whom two had von Hippel-Lindau syndrome. Visual acuity improved in three patients (mean 4.8 lines; range 3-10) and remained stable at 0.0 logMAR in one patient. There were no intraoperative complications. Postoperative complications included transient mild vitreous haemorrhage (n = 2), and local epiretinal membrane formation at the excision location (n = 1). At 4 years postoperatively, there were no long-term complications. There was one case of a new lesion, which was effectively treated with laser. Vitrectomy with RH excision seems to be an effective approach for larger RHs and could be considered an early treatment option in selected cases. Postoperative complications were limited in scope of this case series. Important points to consider during vitrectomy are effective closure of feeder and draining vessels as well as complete removal of posterior hyaloid and epiretinal membranes in order to avoid postoperative vitreous haemorrhage and proliferative vitreoretinopathy. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  1. Membrane Assisted Enzyme Fractionation

    DEFF Research Database (Denmark)

    Yuan, Linfeng

    to the variation in size of the proteins and a reasonable separation factor can be observed only when the size difference is in the order of 10 or more. This is partly caused by concentration polarization and membrane fouling which hinders an effective separation of the proteins. Application of an electric field...... across the porous membrane has been demonstrated to be an effective way to reduce concentration polarization and membrane fouling. In addition, this technique can also be used to separate the proteins based on difference in charge, which to some extent overcome the limitations of size difference...... of proteins on the basis of their charge, degree of hydrophobicity, affinity or size. Adequate purity is often not achieved unless several purification steps are combined thereby increasing cost and reducing product yield. Conventional fractionation of proteins using ultrafiltration membranes is limited...

  2. Fuel cell membrane humidification

    Science.gov (United States)

    Wilson, Mahlon S.

    1999-01-01

    A polymer electrolyte membrane fuel cell assembly has an anode side and a cathode side separated by the membrane and generating electrical current by electrochemical reactions between a fuel gas and an oxidant. The anode side comprises a hydrophobic gas diffusion backing contacting one side of the membrane and having hydrophilic areas therein for providing liquid water directly to the one side of the membrane through the hydrophilic areas of the gas diffusion backing. In a preferred embodiment, the hydrophilic areas of the gas diffusion backing are formed by sewing a hydrophilic thread through the backing. Liquid water is distributed over the gas diffusion backing in distribution channels that are separate from the fuel distribution channels.

  3. Wrinkles in reinforced membranes

    Science.gov (United States)

    Takei, Atsushi; Brau, Fabian; Roman, Benoît; Bico, José.

    2012-02-01

    We study, through model experiments, the buckling under tension of an elastic membrane reinforced with a more rigid strip or a fiber. In these systems, the compression of the rigid layer is induced through Poisson contraction as the membrane is stretched perpendicularly to the strip. Although strips always lead to out-of-plane wrinkles, we observe a transition from out-of-plane to in plane wrinkles beyond a critical strain in the case of fibers embedded into the elastic membranes. The same transition is also found when the membrane is reinforced with a wall of the same material depending on the aspect ratio of the wall. We describe through scaling laws the evolution of the morphology of the wrinkles and the different transitions as a function of material properties and stretching strain.

  4. Novel Catalytic Membrane Reactors

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-02-01

    This factsheet describes a research project that will focus on the development and application of nonporous high gas flux perfluoro membranes with high temperature rating and excellent chemical resistance.

  5. Temperature responsive track membranes

    International Nuclear Information System (INIS)

    Omichi, H.; Yoshido, M.; Asano, M.; Tamada, H.

    1994-01-01

    A new track membrane was synthesized by introducing polymeric hydrogel to films. Such a monomer as amino acid group containing acryloyl or methacryloyl was either co-polymerized with diethylene glycol-bis-ally carbonate followed by on beam irradiation and chemical etching, or graft co-polymerized onto a particle track membrane of CR-39. The pore size was controlled in water by changing the water temperature. Some films other than CR-39 were also examined. (author). 11 refs, 7 figs

  6. Surgical strategies in childhood craniopharyngioma

    Directory of Open Access Journals (Sweden)

    Jörg eFlitsch

    2011-12-01

    Full Text Available Craniopharyngiomas are biologically benign lesions (WHO Grade 1 of the sellar and suprasellar region, associated with a serious morbidity. About 50% of these tumors become clinically apparent during childhood. Clinical symptoms include headaches, chiasm syndrome, hydrocephalus, pituitary insufficiencies, and obesity. Growth arrest is a typical symptom in children. The treatment of craniopharyngiomas includes surgery as well as radiotherapy. The goal of surgery varies according to the tumor location and extension and may range from complete resection to biopsy. Surgical complications are well known and cause constant evaluation of surgical strategies. Diencephalic obesity is related to surgical manipulation of hypothalamic tissue. Therefore, a classification system for craniopharyngiomas based on preoperative MRI is suggested by the authors, which may help assess the surgical risk. Recurrences are frequent in craniopharyngiomas, even after complete or gross-total resection. Radiotherapy is therefore recommended to patients with incomplete resections. However, the ideal time for radiotherapy after surgery is under discussion.The treatment of craniopharyngiomas requires an interdisciplinary and multimodal approach. Each patient should receive an individually tailored treatment. Surgically, different approaches as well as different degrees of resection can be considered, depending on tumor location and tumor extension.

  7. Surgical Management of Localized Scleroderma.

    Science.gov (United States)

    Lee, Jae Hyun; Lim, Soo Yeon; Lee, Jang Hyun; Ahn, Hee Chang

    2017-09-01

    Localized scleroderma is characterized by a thickening of the skin from excessive collagen deposits. It is not a fatal disease, but quality of life can be adversely affected due to changes in skin appearance, joint contractures, and, rarely, serious deformities of the face and extremities. We present six cases of localized scleroderma in face from our surgical practice. We reviewed six localized scleroderma cases that were initially treated with medication and then received follow-up surgery between April 2003 and February 2015. Six patients had facial lesions. These cases presented with linear dermal sclerosis on the forehead, oval subcutaneous and dermal depression in the cheek. En coup de sabre (n=4), and oval-shaped lesion of the face (n=2) were successfully treated. Surgical methods included resection with or without Z-plasty (n=3), fat graft (n=1), dermofat graft (n=1), and adipofascial free flap (n=1). Deformities of the affected parts were surgically corrected without reoccurrence. We retrospectively reviewed six cases of localized scleroderma that were successfully treated with surgery. And we propose an algorithm for selecting the best surgical approach for individual localized scleroderma cases. Although our cases were limited in number and long-term follow-up will be necessary, we suggest that surgical management should be considered as an option for treating scleroderma patients.

  8. Three-dimensional surgical simulation.

    Science.gov (United States)

    Cevidanes, Lucia H C; Tucker, Scott; Styner, Martin; Kim, Hyungmin; Chapuis, Jonas; Reyes, Mauricio; Proffit, William; Turvey, Timothy; Jaskolka, Michael

    2010-09-01

    In this article, we discuss the development of methods for computer-aided jaw surgery, which allows us to incorporate the high level of precision necessary for transferring virtual plans into the operating room. We also present a complete computer-aided surgery system developed in close collaboration with surgeons. Surgery planning and simulation include construction of 3-dimensional surface models from cone-beam computed tomography, dynamic cephalometry, semiautomatic mirroring, interactive cutting of bone, and bony segment repositioning. A virtual setup can be used to manufacture positioning splints for intraoperative guidance. The system provides further intraoperative assistance with a computer display showing jaw positions and 3-dimensional positioning guides updated in real time during the surgical procedure. The computer-aided surgery system aids in dealing with complex cases with benefits for the patient, with surgical practice, and for orthodontic finishing. Advanced software tools for diagnosis and treatment planning allow preparation of detailed operative plans, osteotomy repositioning, bone reconstructions, surgical resident training, and assessing the difficulties of the surgical procedures before the surgery. Computer-aided surgery can make the elaboration of the surgical plan a more flexible process, increase the level of detail and accuracy of the plan, yield higher operative precision and control, and enhance documentation of cases. 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  9. Inverse colloidal crystal membranes for hydrophobic interaction membrane chromatography.

    Science.gov (United States)

    Vu, Anh T; Wang, Xinying; Wickramasinghe, S Ranil; Yu, Bing; Yuan, Hua; Cong, Hailin; Luo, Yongli; Tang, Jianguo

    2015-08-01

    Hydrophobic interaction membrane chromatography has gained interest due to its excellent performance in the purification of humanized monoclonal antibodies. The membrane material used in hydrophobic interaction membrane chromatography has typically been commercially available polyvinylidene fluoride. In this contribution, newly developed inverse colloidal crystal membranes that have uniform pores, high porosity and, therefore, high surface area for protein binding are used as hydrophobic interaction membrane chromatography membranes for humanized monoclonal antibody immunoglobulin G purification. The capacity of the inverse colloidal crystal membranes developed here is up to ten times greater than commercially available polyvinylidene fluoride membranes with a similar pore size. This work highlights the importance of developing uniform pore size high porosity membranes in order to maximize the capacity of hydrophobic interaction membrane chromatography. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Fabrication of electrospun nanofibrous membranes for membrane distillation application

    KAUST Repository

    Francis, Lijo

    2013-02-01

    Nanofibrous membranes of Matrimid have been successfully fabricated using an electrospinning technique under optimized conditions. Nanofibrous membranes are found to be highly hydrophobic with a high water contact angle of 130°. Field emission scanning electron microscopy and pore size distribution analysis revealed the big pore size structure of electrospun membranes to be greater than 2 μm and the pore size distribution is found to be narrow. Flat sheet Matrimid membranes were fabricated via casting followed by phase inversion. The morphology, pore size distribution, and water contact angle were measured and compared with the electrospun membranes. Both membranes fabricated by electrospinning and phase inversion techniques were tested in a direct contact membrane distillation process. Electrospun membranes showed high water vapor flux of 56 kg/m2-h, which is very high compared to the casted membrane as well as most of the fabricated and commercially available highly hydrophobic membranes. ©2013 Desalination Publications.

  11. Far Western: probing membranes.

    Science.gov (United States)

    Einarson, Margret B; Pugacheva, Elena N; Orlinick, Jason R

    2007-08-01

    INTRODUCTIONThe far-Western technique described in this protocol is fundamentally similar to Western blotting. In Western blots, an antibody is used to detect a query protein on a membrane. In contrast, in a far-Western blot (also known as an overlay assay) the antibody is replaced by a recombinant GST fusion protein (produced and purified from bacteria), and the assay detects the interaction of this protein with target proteins on a membrane. The membranes are washed and blocked, incubated with probe protein, washed again, and subjected to autoradiography. The GST fusion (probe) proteins are often labeled with (32)P; alternatively, the membrane can be probed with unlabeled GST fusion protein, followed by detection using commercially available GST antibodies. The nonradioactive approach is substantially more expensive (due to the purchase of antibody and detection reagents) than using radioactively labeled proteins. In addition, care must be taken to control for nonspecific interactions with GST alone and a signal resulting from antibody cross-reactivity. In some instances, proteins on the membrane are not able to interact after transfer. This may be due to improper folding, particularly in the case of proteins expressed from a phage expression library. This protocol describes a way to overcome this by washing the membrane in denaturation buffer, which is then serially diluted to permit slow renaturation of the proteins.

  12. OXYGEN TRANSPORT CERAMIC MEMBRANES

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2000-10-01

    This is the third quarterly report on oxygen Transport Ceramic Membranes. In the following, the report describes the progress made by our university partners in Tasks 1 through 6, experimental apparatus that was designed and built for various tasks of this project, thermodynamic calculations, where applicable and work planned for the future. (Task 1) Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. (Task 2) Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. (Task 3) Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. (Task 4) Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. (Task 5) Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. (Task 6) Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques.

  13. Bacterial membrane proteomics.

    Science.gov (United States)

    Poetsch, Ansgar; Wolters, Dirk

    2008-10-01

    About one quarter to one third of all bacterial genes encode proteins of the inner or outer bacterial membrane. These proteins perform essential physiological functions, such as the import or export of metabolites, the homeostasis of metal ions, the extrusion of toxic substances or antibiotics, and the generation or conversion of energy. The last years have witnessed completion of a plethora of whole-genome sequences of bacteria important for biotechnology or medicine, which is the foundation for proteome and other functional genome analyses. In this review, we discuss the challenges in membrane proteome analysis, starting from sample preparation and leading to MS-data analysis and quantification. The current state of available proteomics technologies as well as their advantages and disadvantages will be described with a focus on shotgun proteomics. Then, we will briefly introduce the most abundant proteins and protein families present in bacterial membranes before bacterial membrane proteomics studies of the last years will be presented. It will be shown how these works enlarged our knowledge about the physiological adaptations that take place in bacteria during fine chemical production, bioremediation, protein overexpression, and during infections. Furthermore, several examples from literature demonstrate the suitability of membrane proteomics for the identification of antigens and different pathogenic strains, as well as the elucidation of membrane protein structure and function.

  14. Biomimetic membranes and methods of making biomimetic membranes

    Science.gov (United States)

    Rempe, Susan; Brinker, Jeffrey C.; Rogers, David Michael; Jiang, Ying-Bing; Yang, Shaorong

    2016-11-08

    The present disclosure is directed to biomimetic membranes and methods of manufacturing such membranes that include structural features that mimic the structures of cellular membrane channels and produce membrane designs capable of high selectivity and high permeability or adsorptivity. The membrane structure, material and chemistry can be selected to perform liquid separations, gas separation and capture, ion transport and adsorption for a variety of applications.

  15. Polyurethane Nanofiber Membranes for Waste Water Treatment by Membrane Distillation

    OpenAIRE

    Jiříček, T.; Komárek, M.; Lederer, T.

    2017-01-01

    Self-sustained electrospun polyurethane nanofiber membranes were manufactured and tested on a direct-contact membrane distillation unit in an effort to find the optimum membrane thickness to maximize flux rate and minimize heat losses across the membrane. Also salt retention and flux at high salinities up to 100 g kg−1 were evaluated. Even though the complex structure of nanofiber layers has extreme specific surface and porosity, membrane performance was surprisingly predictable; the highest ...

  16. Surgical Approaches to Chronic Pancreatitis

    Directory of Open Access Journals (Sweden)

    Daniel Hartmann

    2015-01-01

    Full Text Available Chronic pancreatitis is a progressive inflammatory disease resulting in permanent structural damage of the pancreas. It is mainly characterized by recurring epigastric pain and pancreatic insufficiency. In addition, progression of the disease might lead to additional complications, such as pseudocyst formation or development of pancreatic cancer. The medical and surgical treatment of chronic pancreatitis has changed significantly in the past decades. With regard to surgical management, pancreatic head resection has been shown to be a mainstay in the treatment of severe chronic pancreatitis because the pancreatic head mass is known to trigger the chronic inflammatory process. Over the years, organ-preserving procedures, such as the duodenum-preserving pancreatic head resection and the pylorus-preserving Whipple, have become the surgical standard and have led to major improvements in pain relief, preservation of pancreatic function, and quality of life of patients.

  17. Surgical management of Gerhardt syndrome.

    Science.gov (United States)

    Chirilă, M; Mureşan, R; Cosgarea, M; Tomescu, E

    2010-01-01

    Adduction bilateral vocal fold immobility syndrome may be due by both recurrent laryngeal nerves paralysis--Gerhardt syndrome--and all intrinsic laryngeal muscles paralysis--Riegel syndrome. Etiology of Gerhardt syndrome is thyroid surgery, intubation's maneuver, trauma, neurological disorders, extrala-ryngeal malignancies. The manifestations of Gerhardt syndrome are inspiratory dyspnea and slightly influenced voicing by paramedian vocal folds paralysis with an important narrowing of the airway at the glottic level. The surgical procedures for enlargement of the glottic space can be classified in many ways and their major characteristics are: changes at the glottic level; surgical approach: open neck or endoscopic, with or without opening of the mucosal lining; the need for tracheostomy; the equipment used. The aim of this review is to expound the variety of interventions through the last century marked by the development of the diagnostic methods, the anesthesia and the surgical armament with sophisticated instruments and technologies.

  18. Surgical ethics: today and tomorrow.

    Science.gov (United States)

    Sade, Robert M; Kavarana, Minoo N

    2017-11-01

    Ethical behavior has always been deeply ingrained in surgical culture, but ethical deliberation has only recently become an important component of cardiac surgical practice. In our earlier review, we covered a range of issues including several related to informed consent, conflict of interest, professional self-regulation and innovation, among many others. This update covers several topics of interest to cardiac surgeons and cardiologists, focusing on controversial issues specific to the practice of cardiothoracic surgery: informed consent, relations with hospitals and euthanasia and physician-assisted suicide. The future holds much uncertainty for cardiac surgical practice, research and culture, and we provide an update on ethical issues to serve as a platform for envisioning what is to come.

  19. A cell culture technique for human epiretinal membranes to describe cell behavior and membrane contraction in vitro.

    Science.gov (United States)

    Wertheimer, Christian; Eibl-Lindner, Kirsten H; Compera, Denise; Kueres, Alexander; Wolf, Armin; Docheva, Denitsa; Priglinger, Siegfried G; Priglinger, Claudia; Schumann, Ricarda G

    2017-11-01

    To introduce a human cell culture technique for investigating in-vitro behavior of primary epiretinal cells and membrane contraction of fibrocellular tissue surgically removed from eyes with idiopathic macular pucker. Human epiretinal membranes were harvested from ten eyes with idiopathic macular pucker during standard vitrectomy. Specimens were fixed on cell culture plastic using small entomological pins to apply horizontal stress to the tissue, and then transferred to standard cell culture conditions. Cell behavior of 400 epiretinal cells from 10 epiretinal membranes was observed in time-lapse microscopy and analyzed in terms of cell migration, cell velocity, and membrane contraction. Immunocytochemistry was performed for cell type-specific antigens. Cell specific differences in migration behavior were observed comprising two phenotypes: (PT1) epiretinal cells moving fast, less directly, with small round phenotype and (PT2) epiretinal cells moving slowly, directly, with elongated large phenotype. No mitosis, no outgrowth and no migration onto the plastic were seen. Horizontal contraction measurements showed variation between specimens. Masses of epiretinal cells with a myofibroblast-like phenotype expressed cytoplasmatic α-SMA stress fibers and correlated with cell behavior characteristics (PT2). Fast moving epiretinal cells (PT1) were identified as microglia by immunostaining. This in-vitro technique using traction application allows for culturing surgically removed epiretinal membranes from eyes with idiopathic macular pucker, demonstrating cell behavior and membrane contraction of primary human epiretinal cells. Our findings emphasize the abundance of myofibroblasts, the presence of microglia and specific differences of cell behavior in these membranes. This technique has the potential to improve the understanding of pathologies at the vitreomacular interface and might be helpful in establishing anti-fibrotic treatment strategies.

  20. Surgically Assisted Rapid Maxillary Expansion: surgical and orthodontic aspects

    NARCIS (Netherlands)

    M.J. Koudstaal (Maarten)

    2008-01-01

    textabstractThe scope of this thesis is to shed more light, from a number of perspectives, on surgically assisted rapid maxillary expansion (SARME). The primary questions this thesis set out to answer were; ‘is there a difference in stability between bone-borne and tooth-borne distraction?’ and ‘can

  1. Emotions in veterinary surgical students

    DEFF Research Database (Denmark)

    Langebæk, Rikke; Eika, Berit; Pedersen, Lene Tanggaard

    2012-01-01

    A surgical educational environment is potentially stressful and can negatively affect students' learning. The aim of the present study was to investigate the emotions experienced by veterinary students in relation to their first encounter with live-animal surgery and to identify possible sources...... of positive and negative emotions, respectively. During a Basic Surgical Skills course, 155 veterinary fourth-year students completed a survey. Of these, 26 students additionally participated in individual semi-structured interviews. The results of the study show that students often experienced a combination...

  2. Non-vascular surgical mediastinum

    International Nuclear Information System (INIS)

    Schiavon, S.; Trenaghi, P.; Nardini, S.; Pagan, V.

    1989-01-01

    A review was made of the chest X-ray features of 120 patients who underwent surgical treatment for mediastinal non-vascular pathologies over the past 12 years in the Mestre Hospital. A method of analysis is proposed which takes into account not only the differences between the immediate post-operative period and the follow-up, but also the anatomotopographic partition and the surgical practice. Normal and pathological patterns for both of the above periods are described. The ''dimness'' of the arial tracheogram is emphasized as a usefull and early sign of mediastinal recurrence

  3. Surgical options after Fontan failure

    DEFF Research Database (Denmark)

    van Melle, Joost P; Wolff, Djoeke; Hörer, Jürgen

    2016-01-01

    by the European Congenital Heart Surgeons Association among 22 member centres. Outcome of surgery to address failing Fontan was collected in 225 patients among which were patients with Fontan takedown (n=38; 17%), Fontan conversion (n=137; 61%) or HTX (n=50; 22%). RESULTS: The most prevalent indication...... for failing Fontan surgery was arrhythmia (43.6%), but indications differed across the surgical groups (p...OBJECTIVE: The objective of this European multicenter study was to report surgical outcomes of Fontan takedown, Fontan conversion and heart transplantation (HTX) for failing Fontan patients in terms of all-cause mortality and (re-)HTX. METHODS: A retrospective international study was conducted...

  4. Innovation in pediatric surgical education.

    Science.gov (United States)

    Clifton, Matthew S; Wulkan, Mark L

    2015-06-01

    Pediatric surgical training in the United States remained basically unchanged from the model developed by Ladd and Gross in the 1930s until recently. Standardized curriculum and novel evaluation methods are now being implemented. Pediatric Surgical education is currently undergoing a transition to competency-based evaluation and promotion. Unfortunately, there is little data on the efficacy of these changes. This presents an opportunity for further study of how we conduct training, and how we evaluate and promote our trainees. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Recent advances on polymeric membranes for membrane reactors

    KAUST Repository

    Buonomenna, M. G.

    2012-06-24

    Membrane reactors are generally applied in high temperature reactions (>400 °C). In the field of fine chemical synthesis, however, much milder conditions are generally applicable and polymeric membranes were applied without their damage. The successful use of membranes in membrane reactors is primary the result of two developments concerning: (i) membrane materials and (ii) membrane structures. The selection of a suited material and preparation technique depends on the application the membrane is to be used in. In this chapter a review of up to date literature about polymers and configuration catalyst/ membranes used in some recent polymeric membrane reactors is given. The new emerging concept of polymeric microcapsules as catalytic microreactors has been proposed. © 2012 Bentham Science Publishers. All rights reserved.

  6. Flow and fouling in membrane filters: Effects of membrane morphology

    Science.gov (United States)

    Sanaei, Pejman; Cummings, Linda J.

    2015-11-01

    Membrane filters are widely-used in microfiltration applications. Many types of filter membranes are produced commercially, for different filtration applications, but broadly speaking the requirements are to achieve fine control of separation, with low power consumption. The answer to this problem might seem obvious: select the membrane with the largest pore size and void fraction consistent with the separation requirements. However, membrane fouling (an inevitable consequence of successful filtration) is a complicated process, which depends on many parameters other than membrane pore size and void fraction; and which itself greatly affects the filtration process and membrane functionality. In this work we formulate mathematical models that can (i) account for the membrane internal morphology (internal structure, pore size & shape, etc.); (ii) fouling of membranes with specific morphology; and (iii) make some predictions as to what type of membrane morphology might offer optimum filtration performance.

  7. Polyurethane Nanofiber Membranes for Waste Water Treatment by Membrane Distillation

    Directory of Open Access Journals (Sweden)

    T. Jiříček

    2017-01-01

    Full Text Available Self-sustained electrospun polyurethane nanofiber membranes were manufactured and tested on a direct-contact membrane distillation unit in an effort to find the optimum membrane thickness to maximize flux rate and minimize heat losses across the membrane. Also salt retention and flux at high salinities up to 100 g kg−1 were evaluated. Even though the complex structure of nanofiber layers has extreme specific surface and porosity, membrane performance was surprisingly predictable; the highest flux was achieved with the thinnest membranes and the best energy efficiency was achieved with the thickest membranes. All membranes had salt retention above 99%. Nanotechnology offers the potential to find modern solutions for desalination of waste waters, by introducing new materials with revolutionary properties, but new membranes must be developed according to the target application.

  8. Smart membranes for monitoring membrane based desalination processes

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2017-10-12

    Various examples are related to smart membranes for monitoring membrane based process such as, e.g., membrane distillation processes. In one example, a membrane, includes a porous surface and a plurality of sensors (e.g., temperature, flow and/or impedance sensors) mounted on the porous surface. In another example, a membrane distillation (MD) process includes the membrane. Processing circuitry can be configured to monitor outputs of the plurality of sensors. The monitored outputs can be used to determine membrane degradation, membrane fouling, or to provide an indication of membrane replacement or cleaning. The sensors can also provide temperatures or temperature differentials across the porous surface, which can be used to improve modeling or control the MD process.

  9. Physics of biological membranes

    Science.gov (United States)

    Mouritsen, Ole G.

    The biological membrane is a complex system consisting of an aqueous biomolecular planar aggregate of predominantly lipid and protein molecules. At physiological temperatures, the membrane may be considered a thin (˜50Å) slab of anisotropic fluid characterized by a high lateral mobility of the various molecular components. A substantial fraction of biological activity takes place in association with membranes. As a very lively piece of condensed matter, the biological membrane is a challenging research topic for both the experimental and theoretical physicists who are facing a number of fundamental physical problems including molecular self-organization, macromolecular structure and dynamics, inter-macromolecular interactions, structure-function relationships, transport of energy and matter, and interfacial forces. This paper will present a brief review of recent theoretical and experimental progress on such problems, with special emphasis on lipid bilayer structure and dynamics, lipid phase transitions, lipid-protein and lipid-cholesterol interactions, intermembrane forces, and the physical constraints imposed on biomembrane function and evolution. The paper advocates the dual point of view that there are a number of interesting physics problems in membranology and, at the same time, that the physical properties of biomembranes are important regulators of membrane function.

  10. Surgical approach to pineal tumours.

    Science.gov (United States)

    Pluchino, F; Broggi, G; Fornari, M; Franzini, A; Solero, C L; Allegranza, A

    1989-01-01

    During a period of 10 years (1977-1986) 40 cases of tumour of the pineal region have been treated at the Istituto Neurologico "C. Besta"-of Milan. Out of these 40 cases, 27 (67.5%) were in the paediatric (10-15 years) or juvenile (15-20 years) age at the time of operation. Since 1983 a specific diagnostic and therapeutic protocol has been adopted and thereafter direct surgical removal of the tumour was performed only when the neuroradiological investigations were highly suggestive of a benign extrinsic lesion. Sixteen cases in this series underwent direct surgical removal; in the remaining 24 cases stereotactic biopsy of the tumour was performed in the first instance. On the basis of the histological diagnosis obtained by this procedure surgical excision of the tumour (9 cases) or radiotherapy (15 cases) was then performed. 25 cases underwent surgical removal of the lesion. In all the cases the infratentorial supracerebellar approach as introduced by Krause and then modified by Stein was adopted. On analysis of the data of this series it was observed that in 25% of the cases completely benign resectable tumours were found; in 25% of the cases astrocytoma (grade I-II) which could be treated at least by partial removal were present; in 30% of the cases radiosensitive lesions were encountered. In the remaining 20% of the cases highly malignant tumours were found which should be treated only by radiotherapy and/or chemotherapy.

  11. The dutch surgical colorectal audit

    NARCIS (Netherlands)

    Leersum, N.J. van; Snijders, H.S.; Henneman, D.; Kolfschoten, N.E.; Gooiker, G.A.; Berge, M.G. Ten; Eddes, E.H.; Wouters, M.W.; Tollenaar, R.A.E.M.; Bemelman, W.A.; Dam, R.M. van; Elferink, M.A.; Karsten, T.M.; Krieken, J.H. van; Lemmens, V.E.; Rutten, H.J.; Manusama, E.R.; Velde, C.J. van de; Meijerink, W.J.H.J.; Wiggers, T.; Harst, E. van der; Dekker, J.W.T.; Boerma, D.

    2013-01-01

    INTRODUCTION: In 2009, the nationwide Dutch Surgical Colorectal Audit (DSCA) was initiated by the Association of Surgeons of the Netherlands (ASN) to monitor, evaluate and improve colorectal cancer care. The DSCA is currently widely used as a blueprint for the initiation of other audits, coordinated

  12. Surgical treatment of buried penis.

    Science.gov (United States)

    Lipszyc, E; Pfister, C; Liard, A; Mitrofanoff, P

    1997-10-01

    The buried penis is a rare congenital entity, whose treatment is surgical. There are few publications concerning this matter. The authors report on their experience in 10 cases (1990-1995). In this abnormality, the tip of the glans does not project from the pubic or scrotal skin. It is due to: 1) an excessive development of the penile fascia which retracts the penis; 2) insufficient attachment of the penile skin at the base of the penis; 3) often excessive prepubic fat worsens the appearance of the abnormality but does not by itself totally explain it; 4) a tight phimosis is often present. Surgical treatment is necessary because this aspect tends to persist even after puberty. One cannot indeed count on the development at the age of puberty, neither on the diminution of the fat, nor on the simple cure of the phimosis. One must above all ban circumcision which causes the risk of eliminating the skin necessary for reconstruction. The surgical procedure will comprise: 1) a longitudinal dorsal incision extended circumferentially; 2) resection of the thickened fascia penis; 3) anchoring of the deep face of the dermis to the proximal part of the fascia penis at the base of the penis. This surgical procedure has always brought a significant improvement to the appearance of the penis.

  13. Surgical management of tubal pregnancy

    NARCIS (Netherlands)

    Mol, F.

    2013-01-01

    The work presented in this thesis first addresses the magnitude of the clinical problem of surgically treated tubal pregnancy in The Netherlands. Next, we studied the adherence to recommendations from the Dutch guideline on diagnosis and management of ectopic pregnancy. A systematic review and

  14. The Dutch surgical colorectal audit

    NARCIS (Netherlands)

    van Leersum, N. J.; Snijders, H. S.; Henneman, D.; Kolfschoten, N. E.; Gooiker, G. A.; ten Berge, M. G.; Eddes, E. H.; Wouters, M. W. J. M.; Tollenaar, R. A. E. M.; Bemelman, W. A.; van Dam, R. M.; Elferink, M. A.; Karsten, Th M.; van Krieken, J. H. J. M.; Lemmens, V. E. P. P.; Rutten, H. J. T.; Manusama, E. R.; van de Velde, C. J. H.; Meijerink, W. J. H. J.; Wiggers, Th; van der Harst, E.; Dekker, J. W. T.; Boerma, D.

    2013-01-01

    In 2009, the nationwide Dutch Surgical Colorectal Audit (DSCA) was initiated by the Association of Surgeons of the Netherlands (ASN) to monitor, evaluate and improve colorectal cancer care. The DSCA is currently widely used as a blueprint for the initiation of other audits, coordinated by the Dutch

  15. Surgical smoke and infection control.

    NARCIS (Netherlands)

    Alp, E.; Bijl, D.; Bleichrodt, R.P.; Hansson, B.M.; Voss, A.

    2006-01-01

    Gaseous byproducts produced during electrocautery, laser surgery or the use of ultrasonic scalpels are usually referred to as 'surgical smoke'. This smoke, produced with or without a heating process, contains bio-aerosols with viable and non-viable cellular material that subsequently poses a risk of

  16. Surgical training in the Netherlands

    NARCIS (Netherlands)

    Borel-Rinkes, Inne H. M.; Gouma, Dirk J.; Hamming, Jaap F.

    2008-01-01

    Surgical training in the Netherlands has traditionally been characterized by learning on the job under the classic master-trainee doctrine. Over the past decades, it has become regionally organized with intensive structural training courses, and a peer-based quality control system. Recently, the

  17. Liver plasma membranes: an effective method to analyze membrane proteome.

    Science.gov (United States)

    Cao, Rui; Liang, Songping

    2012-01-01

    Plasma membrane proteins are critical for the maintenance of biological systems and represent important targets for the treatment of disease. The hydrophobicity and low abundance of plasma membrane proteins make them difficult to analyze. The protocols given here are the efficient isolation/digestion procedures for liver plasma membrane proteomic analysis. Both protocol for the isolation of plasma membranes and protocol for the in-gel digestion of gel-embedded plasma membrane proteins are presented. The later method allows the use of a high detergent concentration to achieve efficient solubilization of hydrophobic plasma membrane proteins while avoiding interference with the subsequent LC-MS/MS analysis.

  18. Surgical travellers: tapestry to Bayeux.

    Science.gov (United States)

    Hedley-Whyte, John; Milamed, Debra R

    2014-09-01

    The planning for surgery in war was revisited in 1937 when Ian Fraser was elected a member of the Surgical Travellers. At their 1938 Surgical Travellers meeting in Vienna, Ian and Eleanor Fraser were evicted from their hotel room by the Nazis. The 1939 meeting in Belfast discussed the organization of surgery and the conduct of Emergency Medical Service Hospitals in the United Kingdom; the vast majority were to be under civilian government and military control. From 1943 lengthy and informative organizational meetings were held at least monthly under the chairmanship of Sir Alexander Hood, KBE, Head of the RAMC. Surgical Consultants, now Major Generals, Brigadiers or Full Colonels in the British and U.S. Armies stationed in the UK, prepared for the invasion of Europe. The allocation of medical, surgical, nursing and auxiliary responsibilities was delineated. Liaison with the RAF and US Army Air Force was close as it was with the proposed leaders, Ulstermen Brooke and Montgomery. Montgomery chose Arthur Porritt as Surgeon in Chief to Supreme Headquarters Allied Expeditionary Force (SHAEF), and Eisenhower, General Albert W. Kenner. Just after D-Day, Porritt met Ian Fraser, who had waded in on Arromanches Beach. The triage and evacuation plans for Allied casualties had been controversial, particularly as regards Landing Ship Tanks (LSTs). The dispute with the Hood-selected surgeons on one side, against medical and surgical deployment of LSTs, and Admiral Ernest King and Winston Churchill on the other, favouring LST use for surgery and evacuation. King and Churchill were correct but total Allied air superiority allowed wide use of many of the Allies' Dakotas; 10,000 DC-3s were eventually in service. Supported by forty Allied combat planes to each Luftwaffe, the dispute about Landing Ship Tank use in about a fortnight became moot. The multifaceted role of the Princess Royal in the Emergency Medical Services of the United Kingdom and her close liaison with the Consultant

  19. Virtual reality in surgical education.

    Science.gov (United States)

    Ota, D; Loftin, B; Saito, T; Lea, R; Keller, J

    1995-03-01

    Virtual reality (VR) is an emerging technology that can teach surgeons new procedures and can determine their level of competence before they operate on patients. Also VR allows the trainee to return to the same procedure or task several times later as a refresher course. Laparoscopic surgery is a new operative technique which requires the surgeon to observe the operation on a video-monitor and requires the acquisition of new skills. VR simulation could duplicate the operative field and thereby enhance training and reduce the need for expensive animal training models. Our preliminary experience has shown that we have the technology to model tissues and laparoscopic instruments and to develop in real time a VR learning environment for surgeons. Another basic need is to measure competence. Surgical training is an apprenticeship requiring close supervision and 5-7 years of training. Technical competence is judged by the mentor and has always been subjective. If VR surgical simulators are to play an important role in the future, quantitative measurement of competence would have to be part of the system. Because surgical competence is "vague" and is characterized by such terms as "too long, too short" or "too close, too far," it is possible that the principles of fuzzy logic could be used to measure competence in a VR surgical simulator. Because a surgical procedure consists of a series of tasks and each task is a series of steps, we will plan to create two important tasks in a VR simulator and validate their use. These tasks consist of laparoscopic knot tying and laparoscopic suturing. Our hypothesis is that VR in combination with fuzzy logic can educate surgeons and determine when they are competent to perform these procedures on patients.

  20. Aquaporin-2 membrane targeting

    DEFF Research Database (Denmark)

    Olesen, Emma T B; Fenton, Robert A

    2017-01-01

    The targeting of the water channel aquaporin-2 (AQP2) to the apical plasma membrane of kidney collecting duct principal cells is regulated mainly by the antidiuretic peptide hormone arginine vasopressin (AVP). This process is of crucial importance for the maintenance of body water homeostasis...... of aquaporin-2 (AQP2) to the apical plasma membrane of collecting duct (CD) principal cells (10, 20). This process is mainly regulated by the actions of AVP on the type 2 AVP receptor (V2R), although the V1a receptor may also play a minor role (26). The V2R is classified within the group of 7-transmembrane....... For example, 1) stimulation with the nonspecific AC activator forskolin increases AQP2 membrane accumulation in a mouse cortical collecting duct cell line [e.g., Norregaard et al. (16)]; 2) cAMP increases CD water permeability (15); 3) the cAMP-activated protein kinase A (PKA) can phosphorylate AQP2 on its...

  1. Amniotic membrane allografts: development and clinical utility in ophthalmology

    Directory of Open Access Journals (Sweden)

    Rizzuti A

    2014-12-01

    Full Text Available Allison Rizzuti,1,2 Adam Goldenberg,1 Douglas R Lazzaro1,2 1SUNY Downstate Medical Center, 2Kings County Hospital Center, Brooklyn, NY, USA Abstract: Amniotic membrane, the innermost layer of the placenta, is a tissue that promotes epithelialization, while decreasing inflammation, neovascularization, and scarring. It is used in the surgical management of a wide variety of ophthalmic conditions where it functions as a graft or patch in ocular surface reconstruction. The development of new preservation techniques, as well as a sutureless amniotic membrane, has allowed for easier, in-office placement, without the disadvantages of an operating room procedure. The purpose of this review is to describe the historical development of amniotic membrane in ophthalmology and to describe its current clinical applications, particularly focusing on recent advances. Keywords: ocular surface, cornea, stem cells, prokera, allograft, patch, transplantation

  2. Membrane adsorber for endotoxin removal

    Directory of Open Access Journals (Sweden)

    Karina Moita de Almeida

    Full Text Available ABSTRACT The surface of flat-sheet nylon membranes was modified using bisoxirane as the spacer and polyvinyl alcohol as the coating polymer. The amino acid histidine was explored as a ligand for endotoxins, aiming at its application for endotoxin removal from aqueous solutions. Characterization of the membrane adsorber, analysis of the depyrogenation procedures and the evaluation of endotoxin removal efficiency in static mode are discussed. Ligand density of the membranes was around 7 mg/g dry membrane, allowing removal of up to 65% of the endotoxins. The performance of the membrane adsorber prepared using nylon coated with polyvinyl alcohol and containing histidine as the ligand proved superior to other membrane adsorbers reported in the literature. The lack of endotoxin adsorption on nylon membranes without histidine confirmed that endotoxin removal was due to the presence of the ligand at the membrane surface. Modified membranes were highly stable, exhibiting a lifespan of approximately thirty months.

  3. Rhegmatogenous retinal detachment and conventional surgical treatment.

    Science.gov (United States)

    Golubovic, M

    2013-01-01

    The aim of the paper was to present the efficacy and indications for application of conventional surgical treatment of retinal detachment by using external implants, that is,application of encircling band and buckle. This study comprised patients from the University Eye Clinic in Skopje. A total of 33 patients were diagnosed and surgically treated in the period between May 2010 and August 2011. Conventional surgery was applied in smaller number of patients whose changes of the vitreous body were manifested by detachment of posterior hyaloid membrane, syneresis, with appearance of a small number of pigment cells in the vitreous body and synchysis, and the very retina was with fresh detachment without folds or epiretinal changes (that is, PVR A grade). There were a larger number of patients with more distinct proliferative changes of the vitreous body and of the retina, grades PVR B to C1-C2, and who also underwent the same surgical approach. Routine ophthalmologic examinations were performed, including: determination of visual acuity by Snellen's optotypes, determination of eye pressure with Schiotz's tonometer, examination of anterior segment on biomicroscopy, indirect biomicroscopy of posterior eye segment (vitreous body and retina) and examination on biomicroscopy with Goldmann prism, B scan echography of the eyes before and after surgical treatment. Conventional treatment was used by external application of buckle or application of buckle and encircling band. In case of one break, radial buckle was applied and in case of multiple breaks in one quadrant limbus parallel buckle was applied. Besides buckle, encircling band was applied in patients with total or subtotal retinal detachment with already present distinct changes in the vitreous body (PVR B or C1-C2) and degenerative changes in the vitreous body. Breaks were closed with cryopexy. The results obtained have shown that male gender was predominant and that the disease was manifested in younger male adults

  4. Hybrid Filter Membrane

    Science.gov (United States)

    Laicer, Castro; Rasimick, Brian; Green, Zachary

    2012-01-01

    Cabin environmental control is an important issue for a successful Moon mission. Due to the unique environment of the Moon, lunar dust control is one of the main problems that significantly diminishes the air quality inside spacecraft cabins. Therefore, this innovation was motivated by NASA s need to minimize the negative health impact that air-suspended lunar dust particles have on astronauts in spacecraft cabins. It is based on fabrication of a hybrid filter comprising nanofiber nonwoven layers coated on porous polymer membranes with uniform cylindrical pores. This design results in a high-efficiency gas particulate filter with low pressure drop and the ability to be easily regenerated to restore filtration performance. A hybrid filter was developed consisting of a porous membrane with uniform, micron-sized, cylindrical pore channels coated with a thin nanofiber layer. Compared to conventional filter media such as a high-efficiency particulate air (HEPA) filter, this filter is designed to provide high particle efficiency, low pressure drop, and the ability to be regenerated. These membranes have well-defined micron-sized pores and can be used independently as air filters with discreet particle size cut-off, or coated with nanofiber layers for filtration of ultrafine nanoscale particles. The filter consists of a thin design intended to facilitate filter regeneration by localized air pulsing. The two main features of this invention are the concept of combining a micro-engineered straight-pore membrane with nanofibers. The micro-engineered straight pore membrane can be prepared with extremely high precision. Because the resulting membrane pores are straight and not tortuous like those found in conventional filters, the pressure drop across the filter is significantly reduced. The nanofiber layer is applied as a very thin coating to enhance filtration efficiency for fine nanoscale particles. Additionally, the thin nanofiber coating is designed to promote capture of

  5. Mitigating leaks in membranes

    Energy Technology Data Exchange (ETDEWEB)

    Karnik, Rohit N.; Bose, Suman; Boutilier, Michael S.H.; Hadjiconstantinou, Nicolas G.; Jain, Tarun Kumar; O' Hern, Sean C.; Laoui, Tahar; Atieh, Muataz A.; Jang, Doojoon

    2018-02-27

    Two-dimensional material based filters, their method of manufacture, and their use are disclosed. In one embodiment, a membrane may include an active layer including a plurality of defects and a deposited material associated with the plurality of defects may reduce flow therethrough. Additionally, a majority of the active layer may be free from the material. In another embodiment, a membrane may include a porous substrate and an atomic layer deposited material disposed on a surface of the porous substrate. The atomic layer deposited material may be less hydrophilic than the porous substrate and an atomically thin active layer may be disposed on the atomic layer deposited material.

  6. Membrane accessibility of glutathione

    DEFF Research Database (Denmark)

    Garcia, Almudena; Eljack, N., D.; Sani, ND

    2015-01-01

    Regulation of the ion pumping activity of the Na(+),K(+)-ATPase is crucial to the survival of animal cells. Recent evidence has suggested that the activity of the enzyme could be controlled by glutathionylation of cysteine residue 45 of the β-subunit. Crystal structures so far available indicate...... that this cysteine is in a transmembrane domain of the protein. Here we have analysed via fluorescence and NMR spectroscopy as well as molecular dynamics simulations whether glutathione is able to penetrate into the interior of a lipid membrane. No evidence for any penetration of glutathione into the membrane...

  7. Fouling resistant membrane spacers

    KAUST Repository

    Ghaffour, Noreddine

    2017-10-12

    Disclosed herein are spacers having baffle designs and perforations for efficiently and effectively separating one or more membrane layers a membrane filtration system. The spacer (504) includes a body (524) formed at least in part by baffles (520) that are interconnected, and the baffles define boundaries of openings or apertures (525) through a thickness direction of the body of the spacer. Alternatively or additionally, passages or perforations (526A, 526B) may be present in the spacer layer or baffles for fluid flow there through, with the passages and baffles having a numerous different shapes and sizes.

  8. Organic separations with membranes

    International Nuclear Information System (INIS)

    Funk, E.W.

    1993-01-01

    This paper presents an overview of present and emerging applications of membrane technology for the separation and purification of organic materials. This technology is highly relevant for programs aimed at minimizing waste in processing and in the treatment of gaseous and liquid effluents. Application of membranes for organic separation is growing rapidly in the petrochemical industry to simplify processing and in the treatment of effluents, and it is expected that this technology will be useful in numerous other industries including the processing of nuclear waste materials

  9. Structure and physical properties of bio membranes and model membranes

    International Nuclear Information System (INIS)

    Tibor Hianik

    2006-01-01

    Bio membranes belong to the most important structures of the cell and the cell organelles. They play not only structural role of the barrier separating the external and internal part of the membrane but contain also various functional molecules, like receptors, ionic channels, carriers and enzymes. The cell membrane also preserves non-equilibrium state in a cell which is crucial for maintaining its excitability and other signaling functions. The growing interest to the bio membranes is also due to their unique physical properties. From physical point of view the bio membranes, that are composed of lipid bilayer into which are incorporated integral proteins and on their surface are anchored peripheral proteins and polysaccharides, represent liquid s crystal of smectic type. The bio membranes are characterized by anisotropy of structural and physical properties. The complex structure of bio membranes makes the study of their physical properties rather difficult. Therefore several model systems that mimic the structure of bio membranes were developed. Among them the lipid monolayers at an air-water interphase, bilayer lipid membranes, supported bilayer lipid membranes and liposomes are most known. This work is focused on the introduction into the physical word of the bio membranes and their models. After introduction to the membrane structure and the history of its establishment, the physical properties of the bio membranes and their models are stepwise presented. The most focus is on the properties of lipid monolayers, bilayer lipid membranes, supported bilayer lipid membranes and liposomes that were most detailed studied. This lecture has tutorial character that may be useful for undergraduate and graduate students in the area of biophysics, biochemistry, molecular biology and bioengineering, however it contains also original work of the author and his co-worker and PhD students, that may be useful also for specialists working in the field of bio membranes and model

  10. Fouling in Membrane Distillation, Osmotic Distillation and Osmotic Membrane Distillation

    Directory of Open Access Journals (Sweden)

    Mourad Laqbaqbi

    2017-03-01

    Full Text Available Various membrane separation processes are being used for seawater desalination and treatment of wastewaters in order to deal with the worldwide water shortage problem. Different types of membranes of distinct morphologies, structures and physico-chemical characteristics are employed. Among the considered membrane technologies, membrane distillation (MD, osmotic distillation (OD and osmotic membrane distillation (OMD use porous and hydrophobic membranes for production of distilled water and/or concentration of wastewaters for recovery and recycling of valuable compounds. However, the efficiency of these technologies is hampered by fouling phenomena. This refers to the accumulation of organic/inorganic deposits including biological matter on the membrane surface and/or in the membrane pores. Fouling in MD, OD and OMD differs from that observed in electric and pressure-driven membrane processes such electrodialysis (ED, membrane capacitive deionization (MCD, reverse osmosis (RO, nanofiltration (NF, ultrafiltration (UF, microfiltration (MF, etc. Other than pore blockage, fouling in MD, OD and OMD increases the risk of membrane pores wetting and reduces therefore the quantity and quality of the produced water or the concentration efficiency of the process. This review deals with the observed fouling phenomena in MD, OD and OMD. It highlights different detected fouling types (organic fouling, inorganic fouling and biofouling, fouling characterization techniques as well as various methods of fouling reduction including pretreatment, membrane modification, membrane cleaning and antiscalants application.

  11. Membrane order in the plasma membrane and endocytic recycling compartment.

    Science.gov (United States)

    Iaea, David B; Maxfield, Frederick R

    2017-01-01

    The cholesterol content of membranes plays an important role in organizing membranes for signal transduction and protein trafficking as well as in modulating the biophysical properties of membranes. While the properties of model or isolated membranes have been extensively studied, there has been little evaluation of internal membranes in living cells. Here, we use a Nile Red based probe, NR12S, and ratiometric live cell imaging, to analyze the membrane order of the plasma membrane and endocytic recycling compartment. We find that after a brief incubation to allow endocytosis, NR12S is distributed between the plasma membrane and the endocytic recycling compartment. The NR12S reports that the endocytic recycling compartment is more highly ordered than the plasma membrane. We also find that the plasma membrane and the endocytic recycling compartment are differentially affected by altering cellular cholesterol levels. The membrane order of the plasma membrane, but not the endocytic recycling compartment, is altered significantly when cellular cholesterol content is increased or decreased by 20%. These results demonstrate that changes in cellular cholesterol differentially alter membrane order within different organelles.

  12. Surgical Masculinization of the Breast: Clinical Classification and Surgical Procedures.

    Science.gov (United States)

    Cardenas-Camarena, Lazaro; Dorado, Carlos; Guerrero, Maria Teresa; Nava, Rosa

    2017-06-01

    Aesthetic breast area improvements for gynecomastia and gender dysphoria patients who seek a more masculine appearance have increased recently. We present our clinical experience in breast masculinization and a classification for these patients. From July 2003 to May 2014, 68 patients seeking a more masculine thorax underwent surgery. They were divided into five groups depending on three factors: excess fatty tissue, breast tissue, and skin. A specific surgical treatment was assigned according to each group. The surgical treatments included thoracic liposuction, subcutaneous mastectomy, periareolar skin resection in one or two stages, and mastectomy with a nipple areola complex graft. The evaluation was performed 6 months after surgery to determine the degree of satisfaction and presence of complications. Surgery was performed on a total of 68 patients, 45 male and 22 female, with ages ranging from 18 to 49 years, and an average age of 33 years. Liposuction alone was performed on five patients; subcutaneous mastectomy was performed on eight patients; subcutaneous mastectomy combined with liposuction was performed on 27 patients; periareolar skin resection was performed on 11 patients; and mastectomy with NAC free grafts was performed on 16 patients. The surgical procedure satisfied 94% of the patients, with very few complications. All patients who wish to obtain a masculine breast shape should be treated with only one objective regardless patient's gender: to obtain a masculine thorax. We recommend a simple mammary gland classification for determining the best surgical treatment for these patients LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  13. Fabrication of electrospun nanofibrous membranes for membrane distillation application

    KAUST Repository

    Francis, Lijo; Maab, Husnul; Alsaadi, Ahmad Salem; Nunes, Suzana Pereira; Ghaffour, NorEddine; Amy, Gary L.

    2013-01-01

    Nanofibrous membranes of Matrimid have been successfully fabricated using an electrospinning technique under optimized conditions. Nanofibrous membranes are found to be highly hydrophobic with a high water contact angle of 130°. Field emission

  14. Giant plasma membrane vesicles: models for understanding membrane organization.

    Science.gov (United States)

    Levental, Kandice R; Levental, Ilya

    2015-01-01

    The organization of eukaryotic membranes into functional domains continues to fascinate and puzzle cell biologists and biophysicists. The lipid raft hypothesis proposes that collective lipid interactions compartmentalize the membrane into coexisting liquid domains that are central to membrane physiology. This hypothesis has proven controversial because such structures cannot be directly visualized in live cells by light microscopy. The recent observations of liquid-liquid phase separation in biological membranes are an important validation of the raft hypothesis and enable application of the experimental toolbox of membrane physics to a biologically complex phase-separated membrane. This review addresses the role of giant plasma membrane vesicles (GPMVs) in refining the raft hypothesis and expands on the application of GPMVs as an experimental model to answer some of key outstanding problems in membrane biology. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. The pregnant female surgical resident

    Directory of Open Access Journals (Sweden)

    Shifflette V

    2018-05-01

    Full Text Available Vanessa Shifflette,1 Susannah Hambright,2 Joseph Darryl Amos,1 Ernest Dunn,3 Maria Allo4 1Associates in Surgical Acute Care, Methodist Dallas Medical Center, Dallas, TX, USA; 2Methodist Surgical Associates, Methodist Dallas Medical Center, Dallas, TX, USA; 3Graduate Medical Education - General Surgery, Methodist Dallas Medical Center, Dallas, TX, USA; 4Santa Clara Valley Medical Center, San Jose, CA, USA Background: Surgery continues to be an intense, time-consuming residency. Many medical students decide against surgery as a profession due to the long work hours and family strain. The pregnant female surgical resident has an added stress factor compared to her male counterpart. Methods: We distributed an electronic, online 26-question survey to 32 general surgery programs in the southwestern region of the United States. Each program distributed our survey to the female surgical residents who had been pregnant during residency in the last 5 years. Each program was re-contacted 6 weeks after the initial contact. Most questions were in a 5-point Likert scale format. The responses were collected and analyzed using the Survey Monkey website. Results: An unvalidated survey was sent to 32 general surgery programs and 26 programs responded (81%. Each program was asked for the total number of possible responses from female residents that met our criteria (60 female residents. Seven of the programs (27% stated that they have had zero residents pregnant. We had 22 residents respond (37%. Over half of the residents (55% were pregnant during their 2nd or 3rd year of residency, with only 18% pregnant during a research year. Thirty-one percent had a lower American Board of Surgery In-Training Exam (ABSITE score. Ninety percent of the residents were able to take 4 weeks or more for maternity leave. Most of the residents (95% stated that they would do this again during residency given the opportunity, but many of the residents felt that returning back to work

  16. Prevention of intra-abdominal adhesion by bi-layer electrospun membrane.

    Science.gov (United States)

    Jiang, Shichao; Wang, Wei; Yan, Hede; Fan, Cunyi

    2013-06-04

    The aim of this study was to compare the anti-adhesion efficacy of a bi-layer electrospun fibrous membrane consisting of hyaluronic acid-loaded poly(ε-caprolactone) (PCL) fibrous membrane as the inner layer and PCL fibrous membrane as the outer layer with a single-layer PCL electrospun fibrous membrane in a rat cecum abrasion model. The rat model utilized a cecal abrasion and abdominal wall insult surgical protocol. The bi-layer and PCL membranes were applied between the cecum and the abdominal wall, respectively. Control animals did not receive any treatment. After postoperative day 14, a visual semiquantitative grading scale was used to grade the extent of adhesion. Histological analysis was performed to reveal the features of adhesion tissues. Bi-layer membrane treated animals showed significantly lower adhesion scores than control animals (p compared with the PCL membrane. Histological analysis of the bi-layer membrane treated rat rarely demonstrated tissue adhesion while that of the PCL membrane treated rat and control rat showed loose and dense adhesion tissues, respectively. Bi-layer membrane can efficiently prevent adhesion formation in abdominal cavity and showed a significantly decreased adhesion tissue formation compared with the control.

  17. Adaptive silicone-membrane lenses: planar vs. shaped membrane

    CSIR Research Space (South Africa)

    Schneider, F

    2009-08-01

    Full Text Available Engineering, Georges-Koehler-Allee 102, Freiburg 79110, Germany florian.schneider@imtek.uni-freiburg.de ABSTRACT We compare the performance and optical quality of two types of adaptive fluidic silicone-membrane lenses. The membranes feature either a...-membrane lenses: planar vs. shaped membrane Florian Schneider1,2, Philipp Waibel2 and Ulrike Wallrabe2 1 CSIR, Materials Science and Manufacturing, PO Box 395, Pretoria 0001, South Africa 2 University of Freiburg – IMTEK, Department of Microsystems...

  18. Nanodisc-solubilized membrane protein library reflects the membrane proteome

    OpenAIRE

    Marty, Michael T.; Wilcox, Kyle C.; Klein, William L.; Sligar, Stephen G.

    2013-01-01

    The isolation and identification of unknown membrane proteins offers the prospect of discovering new pharmaceutical targets and identifying key biochemical receptors. However, interactions between membrane protein targets and soluble ligands are difficult to study in vitro due to the insolubility of membrane proteins in non-detergent systems. Nanodiscs, nanoscale discoidal lipid bilayers encircled by a membrane scaffold protein belt, have proven to be an effective platform to solubilize membr...

  19. Surgical versus non-surgical management of abdominal injury.

    Science.gov (United States)

    Oyo-Ita, Angela; Chinnock, Paul; Ikpeme, Ikpeme A

    2015-11-13

    Injury to the abdomen can be blunt or penetrating. Abdominal injury can damage internal organs such as the liver, spleen, kidneys, intestine, and large blood vessels. There are controversies about the best approach to manage abdominal injuries. To assess the effects of surgical and non-surgical interventions in the management of abdominal trauma in a haemodynamically stable and non-peritonitic abdomen. We searched the Cochrane Injuries Group's Specialised Register, The Cochrane Library, Ovid MEDLINE(R), Ovid MEDLINE(R) In-Process & Other Non-Indexed Citations, Ovid MEDLINE(R) Daily and Ovid OLDMEDLINE(R), EMBASE Classic+EMBASE (Ovid), ISI WOS (SCI-EXPANDED, SSCI, CPCI-S & CPSI-SSH), CINAHL Plus (EBSCO), and clinical trials registers, and screened reference lists. We ran the most recent search on 17 September 2015. Randomised controlled trials of surgical interventions and non-surgical interventions involving people with abdominal injury who were haemodynamically stable with no signs of peritonitis. The abdominal injury could be blunt or penetrating. Two review authors independently applied the selection criteria. Data were extracted by two authors using a standard data extraction form, and are reported narratively. Two studies are included, which involved a total of 114 people with penetrating abdominal injuries. Both studies are at moderate risk of bias because the randomisation methods are not fully described, and the original study protocols are no longer available. The studies were undertaken in Finland between 1992 and 2002, by the same two researchers.In one study, 51 people were randomised to surgery or an observation protocol. None of the participants in the study died. Seven people had complications: 5 (18.5%) in the surgical group and 2 (8.3%) in the observation group; the difference was not statistically significant (P = 0.42; Fischer's exact). Among the 27 people who had surgery, 6 (22.2%) surgeries were negative laparotomies, and 15 (55.6%) were non

  20. Imaging of membranous dysmenorrhea

    Energy Technology Data Exchange (ETDEWEB)

    Rouanet, J.P.; Daclin, P.Y.; Turpin, F.; Karam, R.; Prayssac-Salanon, A. [Dept. of Radiology, C. M. C. Beausoleil, Montpellier (France); Courtieu, C.R. [Dept. of Gynecology, C. M. C. Beausoleil, Montpellier (France); Maubon, A.J. [Dept. of Radiology, C. M. C. Beausoleil, Montpellier (France); Dept. of Radiology, C. H. U. Dupuytren, Limoges (France)

    2001-06-01

    Membranous dysmenorrhea is an unusual clinical entity. It is characterized by the expulsion of huge fragments of endometrium during the menses, favored by hormonal abnormality or drug intake. This report describes a case with clinical, US, and MRI findings before the expulsion. Differential diagnoses are discussed. (orig.)

  1. Imaging of membranous dysmenorrhea

    International Nuclear Information System (INIS)

    Rouanet, J.P.; Daclin, P.Y.; Turpin, F.; Karam, R.; Prayssac-Salanon, A.; Courtieu, C.R.; Maubon, A.J.

    2001-01-01

    Membranous dysmenorrhea is an unusual clinical entity. It is characterized by the expulsion of huge fragments of endometrium during the menses, favored by hormonal abnormality or drug intake. This report describes a case with clinical, US, and MRI findings before the expulsion. Differential diagnoses are discussed. (orig.)

  2. HOLLOW FIBRE MEMBRANE

    NARCIS (Netherlands)

    Wessling, Matthias; Stamatialis, Dimitrios; Kopec, K.K.; Dutczak, S.M.

    2011-01-01

    The present invention relates to a process for manufacturing a hollow fibre membrane having a supporting layer and a separating layer, said process comprising: (a)extruding a spinning composition comprising a first polymer and a solvent for the first polymer through an inner annular orifice of a

  3. HOLLOW FIBRE MEMBRANE

    NARCIS (Netherlands)

    Wessling, Matthias; Stamatialis, Dimitrios; Kopec, K.K.; Dutczak, S.M.

    2013-01-01

    The present invention relates to a process for manufacturing a hollow fibre membrane having a supporting layer and a separating layer, said process comprising: (a) extruding a spinning composition comprising a first polymer and a solvent for the first polymer through an inner annular orifice of a

  4. Fusion of biological membranes

    Indian Academy of Sciences (India)

    Home; Journals; Pramana – Journal of Physics; Volume 64; Issue 6. Fusion of biological membranes. K Katsov M Müller M Schick. Invited Talks:- Topic 11. Biologically motivated problems (protein-folding models, dynamics at the scale of the cell; biological networks, evolution models, etc.) Volume 64 Issue 6 June 2005 pp ...

  5. Membranes and Fluorescence microscopy

    DEFF Research Database (Denmark)

    Bagatolli, Luis

    2009-01-01

    Fluorescence spectroscopy-based techniques using conventional fluorimeters have been extensively applied since the late 1960s to study different aspects of membrane-related phenomena, i.e., mainly relating to lipid-lipid and lipid-protein (peptide) interactions. Even though fluorescence...

  6. Bioelectrochemistry II membrane phenomena

    CERN Document Server

    Blank, M

    1987-01-01

    This book contains the lectures of the second course devoted to bioelectro­ chemistry, held within the framework of the International School of Biophysics. In this course another very large field of bioelectrochemistry, i. e. the field of Membrane Phenomena, was considered, which itself consists of several different, but yet related subfields. Here again, it can be easily stated that it is impossible to give a complete and detailed picture of all membrane phenomena of biological interest in a short course of about one and half week. Therefore the same philosophy, as the one of the first course, was followed, to select a series of lectures at postgraduate level, giving a synthesis of several membrane phenomena chosen among the most'important ones. These lectures should show the large variety of membrane-regulated events occurring in living bodies, and serve as sound interdisciplinary basis to start a special­ ized study of biological phenomena, for which the investigation using the dual approach, physico-che...

  7. Membrane Transfer Phenomena (MTP)

    Science.gov (United States)

    Mason, Larry

    1996-01-01

    Progress has been made in several areas of the definition, design, and development of the Membrane Transport Apparatus (MTA) instrument and associated sensors and systems. Progress is also reported in the development of software modules for instrument control, experimental image and data acquisition, and data analysis.

  8. Extracorporeal membrane oxygenation (ECMO)

    African Journals Online (AJOL)

    Extracorporeal membrane oxygenation (ECMO) is not a novel therapy in the true sense of the ... Intention-to-treat analysis showed benefit for ECMO, with a relative risk ... no doubt that VV-ECMO is an advance in medical technology, and that.

  9. Surgical intervention in patients with necrotizing pancreatitis

    NARCIS (Netherlands)

    Besselink, MG; de Bruijn, MT; Rutten, JP; Boermeester, MA; Hofker, HS; Gooszen, HG

    Background: This study evaluated the various surgical strategies for treatment of (suspected) infected necrotizing pancreatitis (INP) and patient referrals for this condition in the Netherlands. Methods: This retrospective study included all 106 consecutive patients who had surgical treatment for

  10. Deep Neuromuscular Blockade Improves Laparoscopic Surgical Conditions

    DEFF Research Database (Denmark)

    Rosenberg, Jacob; Herring, W Joseph; Blobner, Manfred

    2017-01-01

    INTRODUCTION: Sustained deep neuromuscular blockade (NMB) during laparoscopic surgery may facilitate optimal surgical conditions. This exploratory study assessed whether deep NMB improves surgical conditions and, in doing so, allows use of lower insufflation pressures during laparoscopic cholecys...

  11. Alternative energy efficient membrane bioreactor using reciprocating submerged membrane.

    Science.gov (United States)

    Ho, J; Smith, S; Roh, H K

    2014-01-01

    A novel membrane bioreactor (MBR) pilot system, using membrane reciprocation instead of air scouring, was operated at constant high flux and daily fluctuating flux to demonstrate its application under peak and diurnal flow conditions. Low and stable transmembrane pressure was achieved at 40 l/m(2)/h (LMH) by use of repetitive membrane reciprocation. The results reveal that the inertial forces acting on the membrane fibers effectively propel foulants from the membrane surface. Reciprocation of the hollow fiber membrane is beneficial for the constant removal of solids that may build up on the membrane surface and inside the membrane bundle. The membrane reciprocation in the reciprocating MBR pilot consumed less energy than coarse air scouring used in conventional MBR systems. Specific energy consumption for the membrane reciprocation was 0.072 kWh/m(3) permeate produced at 40 LMH flux, which is 75% less than for a conventional air scouring system as reported in literature without consideration of energy consumption for biological aeration (0.29 kWh/m(3)). The daily fluctuating flux test confirmed that the membrane reciprocation is effective to handle fluctuating flux up to 50 LMH. The pilot-scale reciprocating MBR system successfully demonstrated that fouling can be controlled via 0.43 Hz membrane reciprocation with 44 mm or higher amplitude.

  12. Recent advances on membranes and membrane reactors for hydrogen production

    NARCIS (Netherlands)

    Gallucci, F.; Fernandez Gesalaga, E.; Corengia, P.; Sint Annaland, van M.

    2013-01-01

    Membranes and membrane reactors for pure hydrogen production are widely investigated not only because of the important application areas of hydrogen, but especially because mechanically and chemically stable membranes with high perm-selectivity towards hydrogen are available and are continuously

  13. Influence of membrane properties on fouling in submerged membrane bioreactors

    NARCIS (Netherlands)

    van der Marel, P.; Zwijnenburg, A.; Kemperman, Antonius J.B.; Wessling, Matthias; Temmink, Hardy; van der Meer, Walterus Gijsbertus Joseph

    2010-01-01

    Polymeric flat-sheet membranes with different properties were used in filtration experiments with activated sludge from a pilot-scale MBR to investigate the influence of membrane pore size, surface porosity, pore morphology, and hydrophobicity on membrane fouling. An improved flux-step method was

  14. Nanodisc-solubilized membrane protein library reflects the membrane proteome.

    Science.gov (United States)

    Marty, Michael T; Wilcox, Kyle C; Klein, William L; Sligar, Stephen G

    2013-05-01

    The isolation and identification of unknown membrane proteins offers the prospect of discovering new pharmaceutical targets and identifying key biochemical receptors. However, interactions between membrane protein targets and soluble ligands are difficult to study in vitro due to the insolubility of membrane proteins in non-detergent systems. Nanodiscs, nanoscale discoidal lipid bilayers encircled by a membrane scaffold protein belt, have proven to be an effective platform to solubilize membrane proteins and have been used to study a wide variety of purified membrane proteins. This report details the incorporation of an unbiased population of membrane proteins from Escherichia coli membranes into Nanodiscs. This solubilized membrane protein library (SMPL) forms a soluble in vitro model of the membrane proteome. Since Nanodiscs contain isolated proteins or small complexes, the SMPL is an ideal platform for interactomics studies and pull-down assays of membrane proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the protein population before and after formation of the Nanodisc library indicates that a large percentage of the proteins are incorporated into the library. Proteomic identification of several prominent bands demonstrates the successful incorporation of outer and inner membrane proteins into the Nanodisc library.

  15. Autophagosomal membranes assemble at ER-plasma membrane contact sites.

    Science.gov (United States)

    Nascimbeni, Anna Chiara; Codogno, Patrice; Morel, Etienne

    2017-01-01

    The biogenesis of autophagosome, the double membrane bound organelle related to macro-autophagy, is a complex event requiring numerous key-proteins and membrane remodeling events. Our recent findings identify the extended synaptotagmins, crucial tethers of Endoplasmic Reticulum-plasma membrane contact sites, as key-regulators of this molecular sequence.

  16. Surgical Treatment of Tattoo Complications.

    Science.gov (United States)

    Sepehri, Mitra; Jørgensen, Bo

    2017-01-01

    With a continuing increase in the number of tattoos performed worldwide, the need to treat tattoo complications is growing. Earlier treatments of chronic inflammatory tattoo reactions were dominated by a medical approach, or with no active intervention. In this chapter, we will address modern surgical approaches applied to situations when medical treatment is inefficient and lasers are not applicable. Dermatome shaving is positioned as first-line treatment of allergic tattoo reactions and also indicated in a number of other tattoo reactions, supplemented with excision in selected cases. The methods allow fundamental treatment with removal of the culprit pigment from the dermis. The different instruments, surgical methods, and treatment schedules are reviewed, and a guide to surgeons is presented. Postoperative treatments and the long-term outcomes are described in detail. An algorithm on specialist treatment and follow-up of tattoo reactions, which can be practiced in other countries, is presented. © 2017 S. Karger AG, Basel.

  17. Surgical tools and medical devices

    CERN Document Server

    Jackson, Mark

    2016-01-01

    This new edition presents information and knowledge on the field of biomedical devices and surgical tools. The authors look at the interactions between nanotechnology, nanomaterials, design, modeling, and tools for surgical and dental applications, as well as how nanostructured surfaces can be created for the purposes of improving cell adhesion between medical devices and the human body. Each original chapter is revised in this second edition and describes developments in coatings for heart valves, stents, hip and knee joints, cardiovascular devices, orthodontic applications, and regenerative materials such as bone substitutes. There are also 8 new chapters that address: Microvascular anastomoses Inhaler devices used for pulmonary delivery of medical aerosols Surface modification of interference screws Biomechanics of the mandible (a detailed case study) Safety and medical devices The synthesis of nanostructured material Delivery of anticancer molecules using carbon nanotubes Nano and micro coatings for medic...

  18. Surgical treatment of pathological obesity

    International Nuclear Information System (INIS)

    Portie Felix, Antonio; Navarro Sanchez, Gustavo; Hernandez Solar, Abel; Grass Baldoquin, Jorge Alberto; Domloge Fernandez, Joana

    2011-01-01

    The obesity is the chronic non-communicable disease with a higher rate of growth in past 20 years. It is a risk factor for type 2 diabetes mellitus, high blood pressure, cardiovascular and respiratory affections, infertility, sexual and functional impotence, metabolic syndrome, load joint disorders and some types of cancer (breast, colon, prostate). The metabolic bariatric surgery is the surgical treatment more effective for the morbid obesity at long -and medium- term and not the pharmacologic treatment and the isolated diets. The aim of present historical review of the international literature on the evolution of surgical techniques of the bariatric surgery (malabsorption techniques, gastric restrictive techniques and mixed techniques), is to make available to those interested in this subject, a valuable therapeutic tool to be rationally used. (author)

  19. [Surgical correction of cleft palate].

    Science.gov (United States)

    Kimura, F T; Pavia Noble, A; Soriano Padilla, F; Soto Miranda, A; Medellín Rodríguez, A

    1990-04-01

    This study presents a statistical review of corrective surgery for cleft palate, based on cases treated at the maxillo-facial surgery units of the Pediatrics Hospital of the Centro Médico Nacional and at Centro Médico La Raza of the National Institute of Social Security of Mexico, over a five-year period. Interdisciplinary management as performed at the Cleft-Palate Clinic, in an integrated approach involving specialists in maxillo-facial surgery, maxillar orthopedics, genetics, social work and mental hygiene, pursuing to reestablish the stomatological and psychological functions of children afflicted by cleft palate, is amply described. The frequency and classification of the various techniques practiced in that service are described, as well as surgical statistics for 188 patients, which include a total of 256 palate surgeries performed from March 1984 to March 1989, applying three different techniques and proposing a combination of them in a single surgical time, in order to avoid complementary surgery.

  20. Open surgical simulation--a review.

    Science.gov (United States)

    Davies, Jennifer; Khatib, Manaf; Bello, Fernando

    2013-01-01

    Surgical simulation has benefited from a surge in interest over the last decade as a result of the increasing need for a change in the traditional apprentice model of teaching surgery. However, despite the recent interest in surgical simulation as an adjunct to surgical training, most of the literature focuses on laparoscopic, endovascular, and endoscopic surgical simulation with very few studies scrutinizing open surgical simulation and its benefit to surgical trainees. The aim of this review is to summarize the current standard of available open surgical simulators and to review the literature on the benefits of open surgical simulation. Open surgical simulators currently used include live animals, cadavers, bench models, virtual reality, and software-based computer simulators. In the current literature, there are 18 different studies (including 6 randomized controlled trials and 12 cohort studies) investigating the efficacy of open surgical simulation using live animal, bench, and cadaveric models in many surgical specialties including general, cardiac, trauma, vascular, urologic, and gynecologic surgery. The current open surgical simulation studies show, in general, a significant benefit of open surgical simulation in developing the surgical skills of surgical trainees. However, these studies have their limitations including a low number of participants, variable assessment standards, and a focus on short-term results often with no follow-up assessment. The skills needed for open surgical procedures are the essential basis that a surgical trainee needs to grasp before attempting more technical procedures such as laparoscopic procedures. In this current climate of medical practice with reduced hours of surgical exposure for trainees and where the patient's safety and outcome is key, open surgical simulation is a promising adjunct to modern surgical training, filling the void between surgeons being trained in a technique and a surgeon achieving fluency in that

  1. OXYGEN TRANSPORT CERAMIC MEMBRANES

    International Nuclear Information System (INIS)

    Dr. Sukumar Bandopadhyay; Dr. Nagendra Nagabhushana

    2001-01-01

    Conversion of natural gas to liquid fuels and chemicals is a major goal for the Nation as it enters the 21st Century. Technically robust and economically viable processes are needed to capture the value of the vast reserves of natural gas on Alaska's North Slope, and wean the Nation from dependence on foreign petroleum sources. Technologies that are emerging to fulfill this need are all based syngas as an intermediate. Syngas (a mixture of hydrogen and carbon monoxide) is a fundamental building block from which chemicals and fuels can be derived. Lower cost syngas translates directly into more cost-competitive fuels and chemicals. The currently practiced commercial technology for making syngas is either steam methane reforming (SMR) or a two-step process involving cryogenic oxygen separation followed by natural gas partial oxidation (POX). These high-energy, capital-intensive processes do not always produce syngas at a cost that makes its derivatives competitive with current petroleum-based fuels and chemicals. This project has the following 6 main tasks: Task 1--Design, fabricate and evaluate ceramic to metal seals based on graded ceramic powder/metal braze joints. Task 2--Evaluate the effect of defect configuration on ceramic membrane conductivity and long term chemical and structural stability. Task 3--Determine materials mechanical properties under conditions of high temperatures and reactive atmospheres. Task 4--Evaluate phase stability and thermal expansion of candidate perovskite membranes and develop techniques to support these materials on porous metal structures. Task 5--Assess the microstructure of membrane materials to evaluate the effects of vacancy-impurity association, defect clusters, and vacancy-dopant association on the membrane performance and stability. Task 6--Measure kinetics of oxygen uptake and transport in ceramic membrane materials under commercially relevant conditions using isotope labeling techniques

  2. Surgical Treatment of Hepatocellular Carcinoma

    Science.gov (United States)

    Zamora-Valdes, Daniel; Taner, Timucin; Nagorney, David M.

    2017-01-01

    Hepatocellular carcinoma (HCC) is a major cause of cancer-related death worldwide. In select patients, surgical treatment in the form of either resection or transplantation offers a curative option. The aims of this review are to (1) review the current American Association for the Study of Liver Diseases/European Association for the Study of the Liver guidelines on the surgical management of HCC and (2) review the proposed changes to these guidelines and analyze the strength of evidence underlying these proposals. Three authors identified the most relevant publications in the literature on liver resection and transplantation for HCC and analyzed the strength of evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) classification. In the United States, the liver allocation system provides priority for liver transplantation to patients with HCC within the Milan criteria. Current evidence suggests that liver transplantation may also be indicated in certain patient groups beyond Milan criteria, such as pediatric patients with large tumor burden or adult patients who are successfully downstaged. Patients with no underlying liver disease may also benefit from liver transplantation if the HCC is unresectable. In patients with no or minimal (compensated) liver disease and solitary HCC ≥2 cm, liver resection is warranted. If liver transplantation is not available or contraindicated, liver resection can be offered to patients with multinodular HCC, provided that the underlying liver disease is not decompensated. Many patients may benefit from surgical strategies adapted to local resources and policies (hepatitis B prevalence, organ availability, etc). Although current low-quality evidence shows better overall survival with aggressive surgical strategies, this approach is limited to select patients. Larger and well-designed prospective studies are needed to better define the benefits and limits of such approach. PMID:28975836

  3. Towards Safe Robotic Surgical Systems

    DEFF Research Database (Denmark)

    Sloth, Christoffer; Wisniewski, Rafael

    2015-01-01

    a controller for motion compensation in beating-heart surgery, and prove that it is safe, i.e., the surgical tool is kept within an allowable distance and orientation of the heart. We solve the problem by simultaneously finding a control law and a barrier function. The motion compensation system is simulated...... from several initial conditions to demonstrate that the designed control system is safe for every admissible initial condition....

  4. Surgical treatment of chest instability

    International Nuclear Information System (INIS)

    Kitka, M.; Masek, M.

    2015-01-01

    Fractures of the ribs is the most common thoracic injury after blunt trauma. Chest wall instability (flail chest) is a common occurrence in the presence of multiple ribs fracture. Unilateral or bilateral fractures more ribs anteriorly or posteriorly will produce enough instability that paradoxical respiratory motion results in hypoventilation of an unacceptable degree. Open approach and surgical stabilisation of the chest preserved pulmonary function, improved pain control, minimized posttraumatic deformities and shorter back to work time. (author)

  5. Surgical management of venous malformations.

    Science.gov (United States)

    Loose, D A

    2007-01-01

    Among vascular malformations, the predominantly venous malformations represent the majority of cases. They form a clinical entity and therefore need clear concepts concerning diagnosis and treatment. This paper presents an overview of contemporary classification as well as tactics and techniques of treatment. According to the Hamburg Classification, predominantly venous malformations are categorized into truncular and extratruncular forms, with truncular forms distinguished as obstructions and dilations, and extratruncular forms as limited or infiltrating. The tactics of treatment represent surgical and non-surgical methods or combined techniques. Surgical approaches utilize different tactics and techniques that are adopted based on the pathologic form and type of the malformation: (I) operation to reduce the haemodynamic activity of the malformation; (II) operation to eliminate the malformation; and (III) reconstructive operation. As for (I), a type of a tactic is the operation to derive the venous flow. In (II), the total or partial removal of the venous malformation is demonstrated subdivided into three different techniques. In this way, the infiltrating as well as the limited forms can be treated. An additional technique is dedicated to the treatment of a marginal vein. Approach (III) involves the treatment of venous aneurysms, where a variety of techniques have been successful. Long-term follow-up demonstrates positive results in 91% of the cases. Congenital predominantly venous malformations should be treated according to the principles developed during the past decades in vascular surgery, interventional treatment and multidisciplinary treatment. The days of predominantly conservative treatment should be relegated to the past. Special skills and experiences are necessary to carry out appropriate surgical strategy, and the required operative techniques should be dictated by the location and type of malformation and associated findings.

  6. Frugal Design and Surgical Robotics

    OpenAIRE

    McKinley, Stephen Alan

    2016-01-01

    A new era of robotic surgery is poised to begin when critical patents held by Intuitive Surgical (IS) expire in 2016. IS market dominance for decades has led to an effective monopoly that will be challenged by several commercial enterprises working on next generation general robotic surgery systems. Robotic surgery has the potential to alleviate the skill-gap between experienced and inexperienced surgeons through the automation of sub-tasks within surgicalprocedures.The primary objective of...

  7. Surgical treatment of radiation proctitis

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Izumi; Sato, Gohei; Okaue, Toyotake; Isobe, Yoshinari; Ohtsu, Akira; Sugimoto, Yuzo (Kansai Electric Power Co., Inc., Osaka (Japan))

    1982-08-01

    Severe radiation proctitis was surgically treated in 8 cases. Colostomy was performed in 2 cases, total resection of the rectum in 2 and proctectomy with colostomy in 4. Perineal abscess developed in the 2 cases with total resection of the rectum. Rather than completely resection of the lesion, a procedure leaving no dead space i.e. proctectomy with colostomy, is desirable for radiation proctitis. Complete preoperative examination of the condition of the underlying disease and possible urinary tract complications is important.

  8. Surgical checklists: the human factor.

    LENUS (Irish Health Repository)

    O Connor, Paul

    2013-05-14

    BACKGROUND: Surgical checklists has been shown to improve patient safety and teamwork in the operating theatre. However, despite the known benefits of the use of checklists in surgery, in some cases the practical implementation has been found to be less than universal. A questionnaire methodology was used to quantitatively evaluate the attitudes of theatre staff towards a modified version of the World Health Organisation (WHO) surgical checklist with relation to: beliefs about levels of compliance and support, impact on patient safety and teamwork, and barriers to the use of the checklist. METHODS: Using the theory of planned behaviour as a framework, 14 semi-structured interviews were conducted with theatre personnel regarding their attitudes towards, and levels of compliance with, a checklist. Based upon the interviews, a 27-item questionnaire was developed and distribute to all theatre personnel in an Irish hospital. RESULTS: Responses were obtained from 107 theatre staff (42.6% response rate). Particularly for nurses, the overall attitudes towards the effect of the checklist on safety and teamworking were positive. However, there was a lack of rigour with which the checklist was being applied. Nurses were significantly more sensitive to the barriers to the use of the checklist than anaesthetists or surgeons. Moreover, anaesthetists were not as positively disposed to the surgical checklist as surgeons and nurse. This finding was attributed to the tendency for the checklist to be completed during a period of high workload for the anaesthetists, resulting in a lack of engagement with the process. CONCLUSION: In order to improve the rigour with which the surgical checklist is applied, there is a need for: the involvement of all members of the theatre team in the checklist process, demonstrated support for the checklist from senior personnel, on-going education and training, and barriers to the implementation of the checklist to be addressed.

  9. [Surgical treatment of supraventricular tachycardia].

    Science.gov (United States)

    Vigano, A N; Minzioni, G; Graffigna, A; Paganini, F; Salerno, J A

    1991-10-01

    The article deals with the modern approaches to the treatment of supraventricular tachycardia . The authors analyse the results of operations in ectopic atrial tachycardias, the Wolff-Parkinson-White syndrome, modal re-entry tachycardias, and atrial fibrillation . The last-named is of most interest because the authors possess experience in a new operation for isolation of the internodal tracts. In all conditions the authors obtained convincing evidence on the efficacy of modern surgical treatment in supraventricular tachycardias.

  10. Quantification of surgical blood loss.

    Science.gov (United States)

    Lee, Marcel H; Ingvertsen, Britt T; Kirpensteijn, Jolle; Jensen, Asger L; Kristensen, Annemarie T

    2006-06-01

    To compare gravimetric and colorimetric methods of quantifying surgical blood loss, and to determine if there is a correlation between preoperative hemostatic tests (buccal mucosa bleeding time [BMBT] and intraoperative blood loss). Prospective clinical study. Dogs (n=15) admitted for cutaneous tumor excision, orthopedic procedure, or exploratory laparotomy. Intraoperative blood loss was quantified by measuring irrigation fluid and weighing surgical sponges used for blood and fluid collection during surgery. Results of gravimetric measurements were then correlated to blood loss quantified using spectrophotometric analysis of hemoglobin (Hb) content. Hemostatic variables including BMBT were measured before surgery and compared with the calculated amount of blood loss. Blood loss quantified by gravimetric measurement showed a significant correlation with colorimetric determination of Hb content in surgical sponges and collected irrigation fluid (r=0.93, P<.0001). BMBT correlated weakly but significantly with intraoperative blood loss (r=0.56, P<.05). Quantifying intraoperative blood loss using spectrophotometric Hb analysis accurately assessed the amount of blood loss; however, it is a time-consuming procedure, primarily applicable as a research tool. Gravimetric evaluation of intraoperative blood loss was found to be an accurate method, which can be recommended for use in a clinical setting. Estimation of blood loss using a gravimetric method is accurate and applicable in the clinical setting and provides surgeons with a simple and objective tool to evaluate intraoperative blood loss.

  11. Is surgical workforce diversity increasing?

    Science.gov (United States)

    Andriole, Dorothy A; Jeffe, Donna B; Schechtman, Kenneth B

    2007-03-01

    We sought to determine the extent to which recent increases in levels of gender and racial diversity in the overall resident-physician workforce were evident among core-surgical specialty resident workforces. Chi-square tests for trend assessed the importance of changes from 1996 to 2004 in proportions of women and African Americans in the surgery-resident workforce. Surgery-resident trends were compared with overall resident workforce trends using two-tailed t-tests to compare regression slopes that quantified rates of change over time. Chi-square tests assessed differences between proportions of women and African Americans in the current overall board-certified workforce and their proportions in the surgery board-certified workforce. From 1996 to 2004, proportions of women increased in all seven surgical specialties studied. Compared with the overall trend toward increasing proportions of women in the resident workforce, the trend in one surgical specialty was larger (obstetrics/gynecology, p 0.05), and two were smaller (each p 0.05). Proportions of African Americans decreased in three specialties (each p workforce, except obstetrics/gynecology, remained lower than in the overall board-certified workforce (each p workforces have persisted since 1996 and will likely perpetuate ongoing surgery board-certified workforce disparities.

  12. [Surgical managment of retinal detachment].

    Science.gov (United States)

    Haritoglou, C; Wolf, A

    2015-05-01

    The detachment of the neurosensory retina from the underlying retinal pigment epithelium can be related to breaks of the retina allowing vitreous fluid to gain access to the subretinal space, to exudative changes of the choroid such as tumours or inflammatory diseases or to excessive tractional forces exerted by interactions of the collagenous vitreous and the retina. Tractional retinal detachment is usually treated by vitrectomy and exudative detachment can be addressed by treatment of the underlying condition in many cases. In rhegmatogenous retinal detachment two different surgical procedures, vitrectomy and scleral buckling, can be applied for functional and anatomic rehabilitation of our patients. The choice of the surgical procedure is not really standardised and often depends on the experience of the surgeon and other more ocular factors including lens status, the number of retinal breaks, the extent of the detachment and the amount of preexisting PVR. Using both techniques, anatomic success rates of over 90 % can be achieved. Especially in young phakic patients scleral buckling offers the true advantage to prevent the progression of cataract formation requiring cataract extraction and intraocular lens implantation. Therefore, scleral buckling should be considered in selected cases as an alternative surgical option in spite of the very important technical refinements in modern vitrectomy techniques. Georg Thieme Verlag KG Stuttgart · New York.

  13. Surgical smoke and ultrafine particles

    Directory of Open Access Journals (Sweden)

    Nowak Dennis

    2008-12-01

    Full Text Available Abstract Background Electrocautery, laser tissue ablation, and ultrasonic scalpel tissue dissection all generate a 'surgical smoke' containing ultrafine ( Methods To measure the amount of generated particulates in 'surgical smoke' during different surgical procedures and to quantify the particle number concentration for operation room personnel a condensation particle counter (CPC, model 3007, TSI Inc. was applied. Results Electro-cauterization and argon plasma tissue coagulation induced the production of very high number concentration (> 100000 cm-3 of particles in the diameter range of 10 nm to 1 μm. The peak concentration was confined to the immediate local surrounding of the production side. In the presence of a very efficient air conditioning system the increment and decrement of ultrafine particle occurrence was a matter of seconds, with accumulation of lower particle number concentrations in the operation room for only a few minutes. Conclusion Our investigation showed a short term very high exposure to ultrafine particles for surgeons and close assisting operating personnel – alternating with longer periods of low exposure.

  14. Uncommon surgical emergencies in neonatology

    Directory of Open Access Journals (Sweden)

    R. Angotti

    2014-12-01

    Full Text Available Objective. Over the past decade, multiple factors have changed the pattern of neonatal surgical emergencies. An increase in prenatal screenings and the development of neonatal tertiary care centres have changed the clinical approach to these kids. Materials and methods. Between 1995 to 2011 were retrospectively reviewed 34 patients with diagnosis of uncommon rare neonatal surgical emergencies at our institute. We analyzed: sex, gestational age, weight at birth, primary pathology, prenatal diagnosis, associated anomalies, age and weight at surgery, clinical presentation, start of oral feeding and hospitalization. The follow-up was performed at 6,12, 24 and 36 months. Results. There were 21 male and 13 female. The gestational age ranged between 28 and 36 weeks. The weight at birth ranged between 700 and 1400 grams. Oral feeding was started between 4th and 10th postoperative day. The average hospitalization was about 70.47 days. To date, all patients have finished the followup. They are healthy. Conclusion. The outcome of the patients with uncommon surgical emergencies is different based on the etiology. Overall survival is generally good but is influenced by the associated anomalies.

  15. Surgical management of radiation enterocolitis

    International Nuclear Information System (INIS)

    Sakaguchi, Masahiro; Katsumi, Masaharu; Ishimoto, Kiwao; Yamamoto, Shinji; Yukawa, Hirofumi; Koh, Kenzo; Yamaguchi, Kazuya; Ohta, Masataka; Hayashido, Motonori

    1986-01-01

    Radiotherapy for malignant tumors is effective and established. However, there are many complications in radiotherapy. A typical complication is radiation enterocolitis. It is difficult to treat severe histological damage to the irradiated tissues. This paper reports our experience with 26 patients with radiation enterocolitis for whom surgical treatment was given during a period of 16 years in our surgical department. The most frequent original disease requiring irradiation was cancer of the cervix uteri (15 cases) which was followed by cancer of the urinary bladder (7 cases). All of these patients had received external 60 Co irradiation. The ileum was the most frequent site of the lesion, followed by the rectum, sigmoid and descending colon. The period between the end of irradiation and the onset of enterocolitis ranged from 2 months to 10 years, with an average of 28 months. The main symptoms were intestinal obstruction in the ileum, and melena and fistula in the rectum and sigmoid colon. Intestinal resection was performed in 10 patients, a bypass operation in 4, and colostomy in 12. As to types of intestinal suture in these cases, Gambee's single layer method was thought useful from our experience. Colostomy as surgical management of melena and fistula did not yield satisfactory results. (author)

  16. Simulation-based surgical education.

    Science.gov (United States)

    Evgeniou, Evgenios; Loizou, Peter

    2013-09-01

    The reduction in time for training at the workplace has created a challenge for the traditional apprenticeship model of training. Simulation offers the opportunity for repeated practice in a safe and controlled environment, focusing on trainees and tailored to their needs. Recent technological advances have led to the development of various simulators, which have already been introduced in surgical training. The complexity and fidelity of the available simulators vary, therefore depending on our recourses we should select the appropriate simulator for the task or skill we want to teach. Educational theory informs us about the importance of context in professional learning. Simulation should therefore recreate the clinical environment and its complexity. Contemporary approaches to simulation have introduced novel ideas for teaching teamwork, communication skills and professionalism. In order for simulation-based training to be successful, simulators have to be validated appropriately and integrated in a training curriculum. Within a surgical curriculum, trainees should have protected time for simulation-based training, under appropriate supervision. Simulation-based surgical education should allow the appropriate practice of technical skills without ignoring the clinical context and must strike an adequate balance between the simulation environment and simulators. © 2012 The Authors. ANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons.

  17. Surgical correction of postoperative astigmatism

    Directory of Open Access Journals (Sweden)

    Lindstrom Richard

    1990-01-01

    Full Text Available The photokeratoscope has increased the understanding of the aspheric nature of the cornea as well as a better understanding of normal corneal topography. This has significantly affected the development of newer and more predictable models of surgical astigmatic correction. Relaxing incisions effectively flatten the steeper meridian an equivalent amount as they steepen the flatter meridian. The net change in spherical equivalent is, therefore, negligible. Poor predictability is the major limitation of relaxing incisions. Wedge resection can correct large degrees of postkeratoplasty astigmatism, Resection of 0.10 mm of tissue results in approximately 2 diopters of astigmatic correction. Prolonged postoperative rehabilitation and induced irregular astigmatism are limitations of the procedure. Transverse incisions flatten the steeper meridian an equivalent amount as they steepen the flatter meridian. Semiradial incisions result in two times the amount of flattening in the meridian of the incision compared to the meridian 90 degrees away. Combination of transverse incisions with semiradial incisions describes the trapezoidal astigmatic keratotomy. This procedure may correct from 5.5 to 11.0 diopters dependent upon the age of the patient. The use of the surgical keratometer is helpful in assessing a proper endpoint during surgical correction of astigmatism.

  18. [Surgical tactics in duodenal trauma].

    Science.gov (United States)

    Ivanov, P A; Grishin, A V

    2004-01-01

    Results of surgical treatment of 61 patients with injuries of the duodenum are analyzed. The causes of injuries were stab-incised wounds in 24 patients, missile wound -- in 7, closed abdominal trauma -- in 26, trauma of the duodenum during endoscopic papillosphincterotomy -- in 4. All the patients underwent surgery. Complications were seen in 32 (52.5%) patients, 21 patients died, lethality was 34.4%. Within the first 24 hours since the trauma 7 patients died due to severe combined trauma, blood loss, 54 patients survived acute period of trauma, including 28 patients after open trauma, 26 -- after closed and 4 -- after trauma of the duodenum during endoscopic papillosphincterotomy. Diagnostic and surgical policies are discussed. Results of treatment depending on kind and time of surgery are regarded. It is demonstrated that purulent complications due to retroperitoneal phlegmona, traumatic pancreatitis, pneumonia are the causes of significant number of unfavorable outcomes. Therefore, it is important to adequately incise and drainage infected parts of retroperitoneal fat tissue with two-lumen drainages. Decompression through duodenal tube is the effective procedure for prophylaxis of suture insufficiency and traumatic pancreatitis. Suppression of pancreatic and duodenal secretion with octreotid improves significantly surgical treatment results.

  19. Surgical Management of Chronic Pancreatitis.

    Science.gov (United States)

    Parekh, Dilip; Natarajan, Sathima

    2015-10-01

    Advances over the past decade have indicated that a complex interplay between environmental factors, genetic predisposition, alcohol abuse, and smoking lead towards the development of chronic pancreatitis. Chronic pancreatitis is a complex disorder that causes significant and chronic incapacity in patients and a substantial burden on the society. Major advances have been made in the etiology and pathogenesis of this disease and the role of genetic predisposition is increasingly coming to the fore. Advances in noninvasive diagnostic modalities now allow for better diagnosis of chronic pancreatitis at an early stage of the disease. The impact of these advances on surgical treatment is beginning to emerge, for example, patients with certain genetic predispositions may be better treated with total pancreatectomy versus lesser procedures. Considerable controversy remains with respect to the surgical management of chronic pancreatitis. Modern understanding of the neurobiology of pain in chronic pancreatitis suggests that a window of opportunity exists for effective treatment of the intractable pain after which central sensitization can lead to an irreversible pain syndrome in patients with chronic pancreatitis. Effective surgical procedures exist for chronic pancreatitis; however, the timing of surgery is unclear. For optimal treatment of patients with chronic pancreatitis, close collaboration between a multidisciplinary team including gastroenterologists, surgeons, and pain management physicians is needed.

  20. Membrane distillation for milk concentration

    NARCIS (Netherlands)

    Moejes, S.N.; Romero Guzman, Maria; Hanemaaijer, J.H.; Barrera, K.H.; Feenstra, L.; Boxtel, van A.J.B.

    2015-01-01

    Membrane distillation is an emerging technology to concentrate liquid products while producing high quality water as permeate. Application for desalination has been studied extensively the past years, but membrane distillation has also potential to produce concentrated food products like

  1. Filtration characteristics in membrane bioreactors

    NARCIS (Netherlands)

    Evenblij, H.

    2006-01-01

    Causes of and remedies for membrane fouling in Membrane Bioreactors for wastewater treatment are only poorly understood and described in scientific literature. A Filtration Characterisation Installation and a measurement protocol were developed with the aim of a) unequivocally determination and

  2. From shell to membrane theory

    International Nuclear Information System (INIS)

    Destuynder, P.

    1981-02-01

    A new formulation of the membrane theory is presented in this paper. The assumptions which allow the Budiansky-Sanders' model or the membrane theory to be deduced from the three-dimensional case are pointed out [fr

  3. Fighting surgical site infections in small animals

    DEFF Research Database (Denmark)

    Verwilghen, Denis; Singh, Ameet

    2015-01-01

    A diverse array of pathogen-related, patient-related, and caretaker-related issues influence risk and prevention of surgical site infections (SSIs). The entire surgical team involved in health care settings in which surgical procedures are performed play a pivotal role in the prevention of SSIs. ...

  4. Journal of Surgical Technique and Case Report

    African Journals Online (AJOL)

    The aim of Journal of Surgical Technique and Case Report is to advance surgical knowledge and practice by promoting the reporting of innovative and reproducible surgical techniques ... Anterior palatal island advancement flap for bone graft coverage: technical note · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  5. Surgical versus non-surgical management for pleural empyema.

    Science.gov (United States)

    Redden, Mark D; Chin, Tze Yang; van Driel, Mieke L

    2017-03-17

    Empyema refers to pus in the pleural space, commonly due to adjacent pneumonia, chest wall injury, or a complication of thoracic surgery. A range of therapeutic options are available for its management, ranging from percutaneous aspiration and intercostal drainage to video-assisted thoracoscopic surgery (VATS) or thoracotomy drainage. Intrapleural fibrinolytics may also be administered following intercostal drain insertion to facilitate pleural drainage. There is currently a lack of consensus regarding optimal treatment. To assess the effectiveness and safety of surgical versus non-surgical treatments for complicated parapneumonic effusion or pleural empyema. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2016, Issue 9), MEDLINE (Ebscohost) (1946 to July week 3 2013, July 2015 to October 2016) and MEDLINE (Ovid) (1 May 2013 to July week 1 2015), Embase (2010 to October 2016), CINAHL (1981 to October 2016) and LILACS (1982 to October 2016) on 20 October 2016. We searched ClinicalTrials.gov and WHO International Clinical Trials Registry Platform for ongoing studies (December 2016). Randomised controlled trials that compared a surgical with a non-surgical method of management for all age groups with pleural empyema. Two review authors independently assessed trials for inclusion and risk of bias, extracted data, and checked the data for accuracy. We contacted trial authors for additional information. We assessed the quality of the evidence using the GRADE approach. We included eight randomised controlled trials with a total of 391 participants. Six trials focused on children and two on adults. Trials compared tube thoracostomy drainage (non-surgical), with or without intrapleural fibrinolytics, to either VATS or thoracotomy (surgical) for the management of pleural empyema. Assessment of risk of bias for the included studies was generally unclear for selection and blinding but low for attrition and reporting bias. Data analyses compared

  6. Fundamentals of membrane bioreactors materials, systems and membrane fouling

    CERN Document Server

    Ladewig, Bradley

    2017-01-01

    This book provides a critical, carefully researched, up-to-date summary of membranes for membrane bioreactors. It presents a comprehensive and self-contained outline of the fundamentals of membrane bioreactors, especially their relevance as an advanced water treatment technology. This outline helps to bring the technology to the readers’ attention, and positions the critical topic of membrane fouling as one of the key impediments to its more widescale adoption. The target readership includes researchers and industrial practitioners with an interest in membrane bioreactors.

  7. Cheap Thin Film Oxygen Membranes

    DEFF Research Database (Denmark)

    2009-01-01

    The present invention provides a membrane, comprising a porous support layer a gas tight electronically and ionically conducting membrane layer and a catalyst layer, characterized in that the electronically and ionically conducting membrane layer is formed from a material having a crystallite...... structure with a crystal size of about 1 to 100 nm, and a method for producing same....

  8. Mesoporous and microporous titania membranes

    NARCIS (Netherlands)

    Sekulic, J.

    2004-01-01

    The research described in this thesis deals with the synthesis and properties of ceramic oxide membrane materials. Since most of the currently available inorganic membranes with required separation properties have limited reliability and long-term stability, membranes made of new oxide materials

  9. Membranes suited for immobilizing biomolecules

    NARCIS (Netherlands)

    2009-01-01

    The present invention relates to flow-through membranes suitable for the immobilization of biomols., methods for the prepn. of such membranes and the use of such membranes for the immobilization of biomols. and subsequent detection of immobilized biomols. The invention concerns a flow-through

  10. Impact of sludge flocs on membrane fouling in membrane bioreactors

    DEFF Research Database (Denmark)

    Christensen, Morten Lykkegaard; Niessen, Wolfgang; Jørgensen, Mads Koustrup

    Membrane bioreactors (MBR) are widely used for wastewater treatment, but membrane fouling reduces membrane performance and thereby increases the cost for membranes and fouling control. Large variation in filtration properties measured as flux decline was observed for the different types of sludges....... Further, the flux could partly be reestablished after the relaxation period depending on the sludge composition. The results underline that sludge properties are important for membrane fouling and that control of floc properties, as determined by the composition of the microbial communities...... and the physico-chemical properties, is an efficient method to reduce membrane fouling in the MBR. High concentration of suspended extracellular substances (EPS) and small particles (up to 10 µm) resulted in pronounced fouling propensity. The membrane fouling resistance was reduced at high concentration...

  11. Pulse radiolysis studies of model membranes

    International Nuclear Information System (INIS)

    Heijman, M.G.J.

    1984-01-01

    In this thesis the influence of the structure of membranes on the processes in cell membranes were examined. Different models of the membranes were evaluated. Pulse radiolysis was used as the technique to examine the membranes. (R.B.)

  12. Hypothermia in a surgical intensive care unit.

    Science.gov (United States)

    Abelha, Fernando J; Castro, Maria A; Neves, Aida M; Landeiro, Nuno M; Santos, Cristina C

    2005-06-06

    Inadvertent hypothermia is not uncommon in the immediate postoperative period and it is associated with impairment and abnormalities in various organs and systems that can lead to adverse outcomes. The aim of this study was to estimate the prevalence, the predictive factors and outcome of core hypothermia on admission to a surgical ICU. All consecutive 185 adult patients who underwent scheduled or emergency noncardiac surgery admitted to a surgical ICU between April and July 2004 were admitted to the study. Tympanic membrane core temperature (Tc) was measured before surgery, on arrival at ICU and every two hours until 6 hours after admission. The following variables were also recorded: age, sex, body weight and height, ASA physical status, type of surgery, magnitude of surgical procedure, anesthesia technique, amount of intravenous fluids administered during anesthesia, use of temperature monitoring and warming techniques, duration of the anesthesia, ICU length of stay, hospital length of stay and SAPS II score. Patients were classified as either hypothermic (Tc 35 degrees C). Univariate analysis and multiple regression binary logistic with an odds ratio (OR) and its 95% Confidence Interval (95%CI) were used to compare the two groups of patients and assess the relationship between each clinical predictor and hypothermia. Outcome measured as ICU length of stay and mortality was also assessed. Prevalence of hypothermia on ICU admission was 57.8%. In univariate analysis temperature monitoring, use of warming techniques and higher previous body temperature were significant protective factors against core hypothermia. In this analysis independent predictors of hypothermia on admission to ICU were: magnitude of surgery, use of general anesthesia or combined epidural and general anesthesia, total intravenous crystalloids administrated and total packed erythrocytes administrated, anesthesia longer than 3 hours and SAPS II scores. In multiple logistic regression analysis

  13. Hypothermia in a surgical intensive care unit

    Directory of Open Access Journals (Sweden)

    Landeiro Nuno M

    2005-06-01

    Full Text Available Abstract Background Inadvertent hypothermia is not uncommon in the immediate postoperative period and it is associated with impairment and abnormalities in various organs and systems that can lead to adverse outcomes. The aim of this study was to estimate the prevalence, the predictive factors and outcome of core hypothermia on admission to a surgical ICU. Methods All consecutive 185 adult patients who underwent scheduled or emergency noncardiac surgery admitted to a surgical ICU between April and July 2004 were admitted to the study. Tympanic membrane core temperature (Tc was measured before surgery, on arrival at ICU and every two hours until 6 hours after admission. The following variables were also recorded: age, sex, body weight and height, ASA physical status, type of surgery, magnitude of surgical procedure, anesthesia technique, amount of intravenous fluids administered during anesthesia, use of temperature monitoring and warming techniques, duration of the anesthesia, ICU length of stay, hospital length of stay and SAPS II score. Patients were classified as either hypothermic (Tc ≤ 35°C or normothermic (Tc> 35°C. Univariate analysis and multiple regression binary logistic with an odds ratio (OR and its 95% Confidence Interval (95%CI were used to compare the two groups of patients and assess the relationship between each clinical predictor and hypothermia. Outcome measured as ICU length of stay and mortality was also assessed. Results Prevalence of hypothermia on ICU admission was 57.8%. In univariate analysis temperature monitoring, use of warming techniques and higher previous body temperature were significant protective factors against core hypothermia. In this analysis independent predictors of hypothermia on admission to ICU were: magnitude of surgery, use of general anesthesia or combined epidural and general anesthesia, total intravenous crystalloids administrated and total packed erythrocytes administrated, anesthesia longer

  14. Use of amniotic membrane in ophthalmology surgery, first cases

    International Nuclear Information System (INIS)

    Aguirre, P.; Ogrodnik, M.T.; Zarate, H; Silva, S.; Azocar, M.; Hitschfeld, M.

    2008-01-01

    The results obtained with the implant of amniotic membranes have propitiated their use in different medical fields.One of the most important barriers that have to be solved is the risk to transmit illness from donor to patient. A cooperative work between the Comision Chilena de Energia Nuclear (CCHEN) and the Complejo de Salud San Borja Arriaran (CSSBA) has been done to prepare the membranes with the main purpose of assuring the quality and effectiveness of the tissue, since the procurement to the moment that it is used as biological apposite. In the production of this radiation sterilized tissue, we have followed a strict protocol that considers selection criteria for each donor, obtainment and processing of each membrane in aseptic conditions including the washing steps, cutting,drying in laminar flow hood, packing and identification.This is followed by sterilization with gamma radiation,quality controls which include the count of colonies formation units and the assurance of sterility. The average size of each membrane was 2 x 2 cm. The membranes have been used in 57 patients since 2002 up to date on surgical procedures of ophthalmology specialty: 38 Pterigeon, 3 Recoverment of anophthalmic cavity, 4 Corneal perforations, 2 Sclera ulcers, 1 extirpation of a conjunctiva inclusion cyst and 1 Reconstruction of Lachrymal sac, with very good results

  15. Membrane microparticles and diseases.

    Science.gov (United States)

    Wu, Z-H; Ji, C-L; Li, H; Qiu, G-X; Gao, C-J; Weng, X-S

    2013-09-01

    Membrane microparticles (MPs) are plasma membrane-derived vesicles shed by various types of activated or apoptotic cells including platelets, monocytes, endothelial cells, red blood cells, and granulocytes. MPs are being increasingly recognized as important regulators of cell-to-cell interactions. Recent evidences suggest they may play important functions not only in homeostasis but also in the pathogenesis of a number of diseases such as vascular diseases, cancer, infectious diseases and diabetes mellitus. Accordingly, inhibiting the production of MPs may serve as a novel therapeutic strategy for these diseases. Here we review recent advances on the mechanism underlying the generation of MPs and the role of MPs in vascular diseases, cancer, diabetes, inflammation, and pathogen infection.

  16. Physics of smectic membranes

    Science.gov (United States)

    Pieranski, P.; Beliard, L.; Tournellec, J.-Ph.; Leoncini, X.; Furtlehner, C.; Dumoulin, H.; Riou, E.; Jouvin, B.; Fénerol, J.-P.; Palaric, Ph.; Heuving, J.; Cartier, B.; Kraus, I.

    1993-03-01

    Due to their layered structure, smectic liquid crystals can form membranes, similar to soap bubbles, that can be spanned on frames. Such smectic membranes have been used extensively as samples in many structural X-ray studies of smectic liquid crystals. In this context they have been considered as very convenient and highly perfect samples but little attention has been paid to the reasons for their existence and to the process of their formation. Our aim here is to address a first list of questions, which are the most urgent to answer. We will also describe experiments and models that have been conceived especially in order to understand the physics of these fascinating systems.

  17. Alcohol skin preparation causes surgical fires.

    Science.gov (United States)

    Rocos, B; Donaldson, L J

    2012-03-01

    Surgical fires are a rare but serious preventable safety risk in modern hospitals. Data from the US show that up to 650 surgical fires occur each year, with up to 5% causing death or serious harm. This study used the National Reporting and Learning Service (NRLS) database at the National Patient Safety Agency to explore whether spirit-based surgical skin preparation fluid contributes to the cause of surgical fires. The NRLS database was interrogated for all incidents of surgical fires reported between 1 March 2004 and 1 March 2011. Each report was scrutinised manually to discover the cause of the fire. Thirteen surgical fires were reported during the study period. Of these, 11 were found to be directly related to spirit-based surgical skin preparation or preparation soaked swabs and drapes. Despite manufacturer's instructions and warnings, surgical fires continue to occur. Guidance published in the UK and US states that spirit-based skin preparation solutions should continue to be used but sets out some precautions. It may be that fire risk should be included in pre-surgical World Health Organization checklists or in the surgical training curriculum. Surgical staff should be aware of the risk that spirit-based skin preparation fluids pose and should take action to minimise the chance of fire occurring.

  18. Radiation effects on cell membranes

    International Nuclear Information System (INIS)

    Koeteles, G.J.

    1982-01-01

    The recent developments in the field of membrane biology of eukaryotic cells result in revival of relevant radiobiological studies. The spatial relations and chemical nature of membrane components provide rather sensitive targets. Experimental data are presented concerning the effects of relatively low doses of X-irradiation and low concentration of tritiated water (HTO) on various receptor functions - concanavalin A, cationized ferritin, poliovirus - of plasma membranes of animal and human cells which point to early and temporary disturbances of the composite structures and functions of membranes. References are given to the multifold roles of radiationinduced membrane phenomena on the development and regeneration of radiation injuries. (orig.)

  19. Radiation effects on cell membranes

    Energy Technology Data Exchange (ETDEWEB)

    Koeteles, G.J.

    1982-11-01

    The recent developments in the field of membrane biology of eukaryotic cells result in revival of relevant radiobiological studies. The spatial relations and chemical nature of membrane components provide rather sensitive targets. Experimental data are presented concerning the effects of relatively low doses of X-irradiation and low concentration of tritiated water (HTO) on various receptor functions - concanavalin A, cationized ferritin, poliovirus - of plasma membranes of animal and human cells which point to early and temporary disturbances of the composite structures and functions of membranes. References are given to the multifold roles of radiationinduced membrane phenomena on the development and regeneration of radiation injuries.

  20. Choroidal neovascular membrane

    OpenAIRE

    Bhatt Nitul; Diamond James; Jalali Subhadra; Das Taraprasad

    1998-01-01

    Choroidal neovascular membrane in the macular area is one of the leading causes of severe visual loss. Usually a manifestation in elderly population, it is often associated with age-related macular degeneration. The current mainstay of management is early diagnosis, usually by fundus examination, aided by angiography and photocoagulation in selected cases. Various other modalities of treatment including surgery are being considered as alternate options, but with limited success. The purpose o...

  1. Generalized chiral membrane dynamics

    International Nuclear Information System (INIS)

    Cordero, R.; Rojas, E.

    2003-01-01

    We develop the dynamics of the chiral superconducting membranes (with null current) in an alternative geometrical approach. Besides of this, we show the equivalence of the resulting description with the one known Dirac-Nambu-Goto (DNG) case. Integrability for chiral string model is obtained using a proposed light-cone gauge. In a similar way, domain walls are integrated by means of a simple Ansatz. (Author)

  2. Membrane Stability Testing

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, D.T. [Westinghouse Savannah River Company, AIKEN, SC (United States)

    1997-09-30

    The Electrosynthesis Co. Inc. (ESC) was contracted by the Westinghouse Savannah River Company to investigate the long term performance and durability of cell components (anode, membrane, cathode) in an electrochemical caustic recovery process using a simulated SRC liquid waste as anolyte solution. This report details the results of two long-term studies conducted using an ICI FM01 flow cell. This cell is designed and has previously been demonstrated to scale up directly into the commercial scale ICI FM21 cell.

  3. Membrane technology applications

    Energy Technology Data Exchange (ETDEWEB)

    Golomb, A

    1990-10-01

    Due to a continuing emphasis on increasing the efficiency of utilizing the Province's electrical energy system, a Membrane Testing and Development Facility (MTDF) has been established at Ontario Hydro Research Division. The MTDF comprises bench-scale and pilot-scale reverse osmosis (RO) and ultrafiltration (UF) systems. RO and UF are membrane separation technologies which with microfiltration (MF) have found numerous industrial applications in wastewater treatment and/or byproduct recovery. Since no phase change is involved in RO and UF, they are more energy efficient separation processes than, say, evaporation or distillation. Initial tests have been carried out to demonstrate the capability of the newly-established MTDF. Bench- and pilot-scale RO treatment, at 4.1 MPa applied pressure, of a simulated nickel plating waste rinse stream was demonstrated. RO membrane rejection efficiencies for nickel were 99+% (in the bench scale test) and 99.9+% (on the pilot scale). Volume reduction factors of about 25 were attained, at purified water flux rates in the range 1 to 1.5 m{sup 3}/m{sup 2} per day. Good correlation was noted between bench-scale and pilot-scale RO test results. Pilot-scale UF of a simulated industrial cutting oil/water waste emulsion at 0.40 MPa gave 99+% oil rejection (pilot scale) at a flux rate of 0.7 m{sup 3}/m{sup 2} per day. A volume reduction of about 5.2 was attained. Overviews of opportunities for membrane separation technology applied to the metal cutting and surface finishing industries, and the food and beverage industry are given. Capabilities (and some present needs) of the MTDF are outlined, with recommendations. 17 refs., 10 figs., 7 tabs.

  4. Electrochemical polymer electrolyte membranes

    CERN Document Server

    Fang, Jianhua; Wilkinson, David P

    2015-01-01

    Electrochemical Polymer Electrolyte Membranes covers PEMs from fundamentals to applications, describing their structure, properties, characterization, synthesis, and use in electrochemical energy storage and solar energy conversion technologies. Featuring chapters authored by leading experts from academia and industry, this authoritative text: Discusses cutting-edge methodologies in PEM material selection and fabricationPoints out important challenges in developing PEMs and recommends mitigation strategies to improve PEM performanceAnalyzes the cur

  5. Accomplishments and challenges of surgical simulation.

    Science.gov (United States)

    Satava, R M

    2001-03-01

    For nearly a decade, advanced computer technologies have created extraordinary educational tools using three-dimensional (3D) visualization and virtual reality. Pioneering efforts in surgical simulation with these tools have resulted in a first generation of simulators for surgical technical skills. Accomplishments include simulations with 3D models of anatomy for practice of surgical tasks, initial assessment of student performance in technical skills, and awareness by professional societies of potential in surgical education and certification. However, enormous challenges remain, which include improvement of technical fidelity, standardization of accurate metrics for performance evaluation, integration of simulators into a robust educational curriculum, stringent evaluation of simulators for effectiveness and value added to surgical training, determination of simulation application to certification of surgical technical skills, and a business model to implement and disseminate simulation successfully throughout the medical education community. This review looks at the historical progress of surgical simulators, their accomplishments, and the challenges that remain.

  6. Using dummies for surgical skills training

    DEFF Research Database (Denmark)

    Langebæk, Rikke

    2011-01-01

    Effective acquisition of a skill requires practise. Therefore it is of great importance to provide veterinary students with opportunities to practice their surgical skills before carrying out surgical procedures on live patients. Some veterinary schools let students perform entire surgical...... procedures on research animals, in order to learn the basic skills along the way. From an ethical point of view it is questionable however to use live research animals for the sole purpose of practising surgery, and also, research animals are very costly. It is therefore necessary to identify alternative...... teaching methods for veterinary surgical training. At the Department of Small Animal Clinical Sciences, Faculty of Life Sciences, a number of low fidelity, stuffed toy animal dummies was developed for the Surgical Skills Lab in order to teach 4th year students the basic surgical skills. In the Surgical...

  7. Neutrons and model membranes

    Science.gov (United States)

    Fragneto, G.

    2012-11-01

    Current research in membrane protein biophysics highlights the emerging role of lipids in shaping membrane protein function. Cells and organisms have developed sophisticated mechanisms for controlling the lipid composition and many diseases are related to the failure of these mechanisms. One of the recent advances in the field is the discovery of the existence of coexisting micro-domains within a single membrane, important for regulating some signaling pathways. Many important properties of these domains remain poorly characterized. The characterization and analysis of bio-interfaces represent a challenge. Performing measurements on these few nanometer thick, soft, visco-elastic and dynamic systems is close to the limits of the available tools and methods. Neutron scattering techniques including small angle scattering, diffraction, reflectometry as well as inelastic methods are rapidly developing for these studies and are attracting an increasing number of biologists and biophysicists at large facilities. This manuscript will review some recent progress in the field and provide perspectives for future developments. It aims at highlighting neutron reflectometry as a versatile method to tackle questions dealing with the understanding and function of biomembranes and their components. The other important scattering methods are only briefly introduced.

  8. Viral membrane fusion

    International Nuclear Information System (INIS)

    Harrison, Stephen C.

    2015-01-01

    Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. - Highlights: • Viral fusion proteins overcome the high energy barrier to lipid bilayer merger. • Different molecular structures but the same catalytic mechanism. • Review describes properties of three known fusion-protein structural classes. • Single-virion fusion experiments elucidate mechanism

  9. Novel Catalytic Membrane Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Stuart Nemser, PhD

    2010-10-01

    There are many industrial catalytic organic reversible reactions with amines or alcohols that have water as one of the products. Many of these reactions are homogeneously catalyzed. In all cases removal of water facilitates the reaction and produces more of the desired chemical product. By shifting the reaction to right we produce more chemical product with little or no additional capital investment. Many of these reactions can also relate to bioprocesses. Given the large number of water-organic compound separations achievable and the ability of the Compact Membrane Systems, Inc. (CMS) perfluoro membranes to withstand these harsh operating conditions, this is an ideal demonstration system for the water-of-reaction removal using a membrane reactor. Enhanced reaction synthesis is consistent with the DOE objective to lower the energy intensity of U.S. industry 25% by 2017 in accord with the Energy Policy Act of 2005 and to improve the United States manufacturing competitiveness. The objective of this program is to develop the platform technology for enhancing homogeneous catalytic chemical syntheses.

  10. Quantum charged rigid membrane

    Energy Technology Data Exchange (ETDEWEB)

    Cordero, Ruben [Departamento de Fisica, Escuela Superior de Fisica y Matematicas del I.P.N., Unidad Adolfo Lopez Mateos, Edificio 9, 07738 Mexico, D.F. (Mexico); Molgado, Alberto [Unidad Academica de Fisica, Universidad Autonoma de Zacatecas, Zacatecas Zac. (Mexico); Rojas, Efrain, E-mail: cordero@esfm.ipn.mx, E-mail: amolgado@fisica.uaz.edu.mx, E-mail: efrojas@uv.mx [Departamento de Fisica, Facultad de Fisica e Inteligencia Artificial, Universidad Veracruzana, 91000 Xalapa, Veracruz (Mexico)

    2011-03-21

    The early Dirac proposal to model the electron as a charged membrane is reviewed. A rigidity term, instead of the natural membrane tension, involving linearly the extrinsic curvature of the worldvolume swept out by the membrane is considered in the action modeling the bubble in the presence of an electromagnetic field. We set up this model as a genuine second-order derivative theory by considering a non-trivial boundary term which plays a relevant part in our formulation. The Lagrangian in question is linear in the bubble acceleration and by means of the Ostrogradski-Hamiltonian approach, we observed that the theory comprises the management of both first- and second-class constraints. We thus show that our second-order approach is robust allowing for a proper quantization. We found an effective quantum potential which permits us to compute bounded states for the system. We comment on the possibility of describing brane world universes by invoking this kind of second-order correction terms.

  11. Quantum charged rigid membrane

    International Nuclear Information System (INIS)

    Cordero, Ruben; Molgado, Alberto; Rojas, Efrain

    2011-01-01

    The early Dirac proposal to model the electron as a charged membrane is reviewed. A rigidity term, instead of the natural membrane tension, involving linearly the extrinsic curvature of the worldvolume swept out by the membrane is considered in the action modeling the bubble in the presence of an electromagnetic field. We set up this model as a genuine second-order derivative theory by considering a non-trivial boundary term which plays a relevant part in our formulation. The Lagrangian in question is linear in the bubble acceleration and by means of the Ostrogradski-Hamiltonian approach, we observed that the theory comprises the management of both first- and second-class constraints. We thus show that our second-order approach is robust allowing for a proper quantization. We found an effective quantum potential which permits us to compute bounded states for the system. We comment on the possibility of describing brane world universes by invoking this kind of second-order correction terms.

  12. Viral membrane fusion

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, Stephen C., E-mail: harrison@crystal.harvard.edu

    2015-05-15

    Membrane fusion is an essential step when enveloped viruses enter cells. Lipid bilayer fusion requires catalysis to overcome a high kinetic barrier; viral fusion proteins are the agents that fulfill this catalytic function. Despite a variety of molecular architectures, these proteins facilitate fusion by essentially the same generic mechanism. Stimulated by a signal associated with arrival at the cell to be infected (e.g., receptor or co-receptor binding, proton binding in an endosome), they undergo a series of conformational changes. A hydrophobic segment (a “fusion loop” or “fusion peptide”) engages the target-cell membrane and collapse of the bridging intermediate thus formed draws the two membranes (virus and cell) together. We know of three structural classes for viral fusion proteins. Structures for both pre- and postfusion conformations of illustrate the beginning and end points of a process that can be probed by single-virion measurements of fusion kinetics. - Highlights: • Viral fusion proteins overcome the high energy barrier to lipid bilayer merger. • Different molecular structures but the same catalytic mechanism. • Review describes properties of three known fusion-protein structural classes. • Single-virion fusion experiments elucidate mechanism.

  13. Use of the carbon dioxide laser in guided tissue regeneration wound healing in the beagle dog

    Science.gov (United States)

    Rossmann, Jeffrey A.; Parlar, Ates; Abdel-Ghaffar, Khaled A.; El-Khouli, Amr M.; Israel, Michael

    1996-04-01

    The concept of guided tissue regeneration (GTR) allowing cells from the periodontal ligament and alveolar bone to repopulate the treated root surface has shown the ability to obtain periodontal new attachment. Healing studies have also shown that conventional GTR therapy still does not exclude all the epithelium. This epithelial proliferation apically interferes with the establishment of the new connective tissue attachment to the root surface. The objective of this research study was to examine whether controlled de-epithelialization with the carbon dioxide laser during the healing phase after periodontal surgery, would retard the apical migration of the epithelium and thereby enhance the results obtained through guided tissue regeneration. Eight beagle dogs were used, the experimental side received de-epithelialization with the CO2 laser in conjunction with flap reflection and surgically created buccal osseous defects. Selected defects on each side were treated with ePTFE periodontal membranes. The laser de-epithelialization was repeated every 10 days until removal of the membranes. The control side received the same surgical treatment without laser application. This experimental design allowed histologic study of the new attachment obtained in defects treated with flap debridement with or without laser de-epithelialization and with or without ePTFE membranes. A statistical analysis was performed on the histometric data from 48 teeth in the 8 dogs after 4 months of healing. The results showed significant amounts of new attachment obtained from all four treatment modalities with no statistically significant differences for any one treatment. However, the trend towards enhanced regeneration with the combined treatment of laser and membrane vs. membrane alone or debridement alone was evident. The histologic analysis revealed a significant amount of newly formed `fat cementum' seen only on the laser treated teeth. This feature was the most remarkable finding of the

  14. The role of student surgical interest groups and surgical Olympiads in anatomical and surgical undergraduate training in Russia.

    Science.gov (United States)

    Dydykin, Sergey; Kapitonova, Marina

    2015-01-01

    Traditional department-based surgical interest groups in Russian medical schools are useful tools for student-based selection of specialty training. They also form a nucleus for initiating research activities among undergraduate students. In Russia, the Departments of Topographical Anatomy and Operative Surgery play an important role in initiating student-led research and providing learners with advanced, practical surgical skills. In tandem with department-led activities, student surgical interest groups prepare learners through surgical competitions, known as "Surgical Olympiads," which have been conducted in many Russian centers on a regular basis since 1988. Surgical Olympiads stimulate student interest in the development of surgical skills before graduation and encourage students to choose surgery as their postgraduate specialty. Many of the participants in these surgical Olympiads have become highly qualified specialists in general surgery, orthopedic surgery, neurosurgery, urology, gynecology, and emergency medicine. The present article emphasizes the role of student interest groups and surgical Olympiads in clinical anatomical and surgical undergraduate training in Russia. © 2015 American Association of Anatomists.

  15. Surgical management of spasmodic torticollis

    Directory of Open Access Journals (Sweden)

    Wael Fouad

    2011-12-01

    Full Text Available Introduction: Spasmodic torticollis (ST is a neuromuscular disorder characterized by uncontrolled clonic and intermittently tonic spasm of the neck muscles. Objective: This retrospective study was done to study clinical picture and to evaluate the surgical results of different surgical procedures in 11 patients who had spasmodic torticollis. Methods: The male to female ratio was 1–2 (4 males and 7 females and their ages ranged from 18 to 65 years. The X-ray of the cervical spine was performed before the operation to exclude cervical disorders that can cause symptoms similar to spasmodic torticollis. MRI of the head and neck was performed in all patients, without finding significant brain lesions. Electromyography of the cervical muscles was performed preoperatively and postoperatively. All cases underwent surgery in the form of variable combinations of ventral rhizotomy of C1, C2+ selective peripheral denervation of neck muscles involved according to the type of torticollis. Mean postoperative follow up period was 24 months. Results: There was no operative mortality. As regards the morbidity, one patient had deficiency of shoulder elevation that was transient and improved after 3 months; one patient had wound infection that responded well to antibiotics after culture and sensitivity. Postoperative dysphagia was found in two cases that improved in one of them after two months. At the last follow up examination period, excellent results were obtained in 55% of patients, good results in 18% of patients, fair results in 18% of patients, and poor results in 9% of cases. Conclusion: There is no standard surgical procedure for treatment of ST; this is adapted to each patient according to type of torticollis. Better results were obtained in simple torticollis (excellent results in 100%, than in complex type (excellent and good results in 33.3%. Keywords: Focal dystonia, Spasmodic torticollis, Anterior rhizotomy, Selective denervation

  16. The surgical treatment of acromegaly.

    Science.gov (United States)

    Buchfelder, Michael; Schlaffer, Sven-Martin

    2017-02-01

    Surgical extraction of as much tumour mass as possible is considered the first step of treatment in acromegaly in many centers. In this article the potential benefits, disadvantages and limitations of operative acromegaly treatment are reviewed. Pertinent literature was selected to provide a review covering current indications, techniques and results of operations for acromegaly. The rapid reduction of tumour volume is an asset of surgery. To date, in almost all patients, minimally invasive, transsphenoidal microscopic or endoscopic approaches are employed. Whether a curative approach is feasible or a debulking procedure is planned, can be anticipated on the basis of preoperative magnetic resonance imaging. The radicality of adenoma resection essentially depends on localization, size and invasive character of the tumour. The normalization rates of growth hormone and IGF-1 secretion, respectively, depend on tumour-related factors such as size, extension, the presence or absence of invasion and the magnitude of IGF-1 and growth hormone oversecretion. However, also surgeon-related factors such as experience and patient load of the centers have been shown to strongly affect surgical results and the rate of complications. As compared to most medical treatments, surgery is relatively cheap since the costs occur only once and not repeatedly. There are several new technical gadgets which aid in the surgical procedure: navigation and variants of intraoperative imaging. For the mentioned reasons, current algorithms of acromegaly management suggest an initial operation, unless the patients are unfit for surgery, refuse an operation or only an unsatisfactory resection is anticipated. A few suggestions are made when a re-operation could be considered.

  17. Disc degeneration: current surgical options

    Directory of Open Access Journals (Sweden)

    C Schizas

    2010-10-01

    Full Text Available Chronic low back pain attributed to lumbar disc degeneration poses a serious challenge to physicians. Surgery may be indicated in selected cases following failure of appropriate conservative treatment. For decades, the only surgical option has been spinal fusion, but its results have been inconsistent. Some prospective trials show superiority over usual conservative measures while others fail to demonstrate its advantages. In an effort to improve results of fusion and to decrease the incidence of adjacent segment degeneration, total disc replacement techniques have been introduced and studied extensively. Short-term results have shown superiority over some fusion techniques. Mid-term results however tend to show that this approach yields results equivalent to those of spinal fusion. Nucleus replacement has gained some popularity initially, but evidence on its efficacy is scarce. Dynamic stabilisation, a technique involving less rigid implants than in spinal fusion and performed without the need for bone grafting, represents another surgical option. Evidence again is lacking on its superiority over other surgical strategies and conservative measures. Insertion of interspinous devices posteriorly, aiming at redistributing loads and relieving pain, has been used as an adjunct to disc removal surgery for disc herniation. To date however, there is no clear evidence on their efficacy. Minimally invasive intradiscal thermocoagulation techniques have also been tried, but evidence of their effectiveness is questioned. Surgery using novel biological solutions may be the future of discogenic pain treatment. Collaboration between clinicians and basic scientists in this multidisciplinary field will undoubtedly shape the future of treating symptomatic disc degeneration.

  18. Parallel artificial liquid membrane extraction

    DEFF Research Database (Denmark)

    Gjelstad, Astrid; Rasmussen, Knut Einar; Parmer, Marthe Petrine

    2013-01-01

    This paper reports development of a new approach towards analytical liquid-liquid-liquid membrane extraction termed parallel artificial liquid membrane extraction. A donor plate and acceptor plate create a sandwich, in which each sample (human plasma) and acceptor solution is separated by an arti......This paper reports development of a new approach towards analytical liquid-liquid-liquid membrane extraction termed parallel artificial liquid membrane extraction. A donor plate and acceptor plate create a sandwich, in which each sample (human plasma) and acceptor solution is separated...... by an artificial liquid membrane. Parallel artificial liquid membrane extraction is a modification of hollow-fiber liquid-phase microextraction, where the hollow fibers are replaced by flat membranes in a 96-well plate format....

  19. Solid-state membrane module

    Science.gov (United States)

    Gordon, John Howard [Salt Lake City, UT; Taylor, Dale M [Murray, UT

    2011-06-07

    Solid-state membrane modules comprising at least one membrane unit, where the membrane unit has a dense mixed conducting oxide layer, and at least one conduit or manifold wherein the conduit or manifold comprises a dense layer and at least one of a porous layer and a slotted layer contiguous with the dense layer. The solid-state membrane modules may be used to carry out a variety of processes including the separating of any ionizable component from a feedstream wherein such ionizable component is capable of being transported through a dense mixed conducting oxide layer of the membrane units making up the membrane modules. For ease of construction, the membrane units may be planar.

  20. Surgical castration, coercion and ethics

    DEFF Research Database (Denmark)

    Ryberg, Jesper; Petersen, Thomas Søbirk

    2014-01-01

    the only means by which these offenders are likely to be released from prison, it is reasonable—and close to the heart of modern medical ethics—to consider whether the offer involves some kind of coercion. However, despite McMillan's seemingly careful consideration of this question, it appears to us......John McMillan's detailed ethical analysis concerning the use of surgical castration of sex offenders in the Czech Republic and Germany is mainly devoted to considerations of coercion.1 This is not surprising. When castration is offered as an option to offenders and, at the same time, constitutes...

  1. Surgical treatment of cleft lip

    Directory of Open Access Journals (Sweden)

    Mateus Domingues Miachon

    Full Text Available We performed a systematic review of the literature on the surgical treatment of cleft lip, emphasizing the prevalence, complications associated with the treatment and the points of disagreement between authors. We conducted a literature cross-sectional search that analyzed publications in books, articles and on the databases SciELO - Scientific Electronic Library Online, PubMed, of the National Center for Biotechnology Information. We conclude that: 1 the severity of the cleft will indicate the technique presenting more advantages; 2 the different approaches indicate that there is no consensus on the optimal technique; and 3 the surgeon experience contributes to choosing the best option.

  2. Surgical treatment of radiation proctitis

    International Nuclear Information System (INIS)

    Maruyama, Izumi; Sato, Gohei; Okaue, Toyotake; Isobe, Yoshinari; Ohtsu, Akira; Sugimoto, Yuzo

    1982-01-01

    Severe radiation proctitis was surgically treated in 8 cases. Colostomy was performed in 2 cases, total resection of the rectum in 2 and proctectomy with colostomy in 4. Perineal abscess developed in the 2 cases with total resection of the rectum. Rather than completely resection of the lesion, a procedure leaving no dead space i.e. proctectomy with colostomy, is desirable for radiation proctitis. Complete preoperative examination of the condition of the underlying disease and possible urinary tract complications is important. (Chiba, N.)

  3. Surgical packages for laparoscopic surgery

    Directory of Open Access Journals (Sweden)

    Bhattacharya K

    2005-01-01

    Full Text Available ′Packages′ are in fashion today for most surgical procedures in various corporate hospitals and this has included laparoscopic procedures too. A package system enables the hospitals to get cost settlements done more easily. Also, it is more convenient for the patients who are aware upfront of the charges. The principal disadvantages seems to be for the surgeon, who may face displeasure of the patient, hospital or insurance agencies apart from forfeiting his personal charges if (a he is a novice in laparoscopic surgery and takes extra time to complete a procedure, (b unforeseen problems occur during surgery, or (c new pathologies are discovered on exploration.

  4. Non-surgical radiofrequency facelift.

    Science.gov (United States)

    Narins, David J; Narins, Rhoda S

    2003-10-01

    There has been considerable interest in using non-ablative methods to rejuvenate the skin. The ThermaCool TC (Thermage Inc.) is a radiofrequency (RF) device that has been introduced to induce tightening of the address the problem of skin via a uniform volumetric heating into the deep dermis tightening, resulting in a 'non-surgical facelift'. Radiofrequency produces a uniform volumetric heating into the deep dermis. Twenty treatment areas in 17 patients were treated to evaluate the efficacy and safety of RF treatment to the brow and jowls. The technique was found to produce gradual tightening in most patients, and there were no adverse effects.

  5. Flux Enhancement in Membrane Distillation Using Nanofiber Membranes

    Directory of Open Access Journals (Sweden)

    T. Jiříček

    2016-01-01

    Full Text Available Membrane distillation (MD is an emerging separation technology, whose largest application potential lies in the desalination of highly concentrated solutions, which are out of the scope of reverse osmosis. Despite many attractive features, this technology is still awaiting large industrial application. The main reason is the lack of commercially available membranes with fluxes comparable to reverse osmosis. MD is a thermal separation process driven by a partial vapour pressure difference. Flux, distillate purity, and thermal efficiency are always in conflict, all three being strictly connected with pore size, membrane hydrophobicity, and thickness. The world has not seen the ideal membrane yet, but nanofibers may offer a solution to these contradictory requirements. Membranes of electrospun PVDF were tested under various conditions on a direct contact (DCMD unit, in order to determine the optimum conditions for maximum flux. In addition, their performance was compared to commonly available PTFE, PE, and PES membranes. It was confirmed that thinner membranes have higher fluxes and a lower distillate purity and also higher energy losses via conduction across the membrane. As both mass and heat transfer are connected, it is best to develop new membranes with a target application in mind, for the specific membrane module and operational conditions.

  6. Retinal Damage Induced by Internal Limiting Membrane Removal

    Directory of Open Access Journals (Sweden)

    Rachel Gelman

    2015-01-01

    Full Text Available The internal limiting membrane (ILM, the basement membrane of the Müller cells, serves as the interface between the vitreous body and the retinal nerve fiber layer. It has a fundamental role in the development, structure, and function of the retina, although it also is a pathologic component in the various vitreoretinal disorders, most notably in macular holes. It was not until understanding of the evolution of idiopathic macular holes and the advent of idiopathic macular hole surgery that the idea of adjuvant ILM peeling in the treatment of tractional maculopathies was explored. Today intentional ILM peeling is a commonly applied surgical technique among vitreoretinal surgeons as it has been found to increase the rate of successful macular hole closure and improve surgical outcomes in other vitreoretinal diseases. Though ILM peeling has refined surgery for tractional maculopathies, like all surgical procedures it is not immune to perioperative risk. The essential role of the ILM to the integrity of the retina and risk of trauma to retinal tissue spurs suspicion with regard to its routine removal. Several authors have investigated the retinal damage induced by ILM peeling and these complications have been manifested across many different diagnostic studies.

  7. Timanoplastia myringoplasty type 1 and in residency surgical results and audiometric

    Directory of Open Access Journals (Sweden)

    Buschle, Mauricio

    2010-12-01

    Full Text Available Introduction: The tympanoplasty aims to reconstruct the tympanic membrane, restoring protection to the middle ear and improve hearing. In this study we evaluated the surgical results and audiometric this surgery, performed in the service of Otorhinolaryngology, HC / UFPR by residents of the second year in the year 2008 and factors that may influence the results. Method: A retrospective study through review of medical records. Results: Among the 31 patients evaluated, there was closure of the perforation in 24 (80% and hearing improvement with reduction or closure of the conductive gap by 60% and 26.7% respectively. Discussion: The success rate of surgery was satisfactory and similar to that found in the literature, and factors such as age, presence of unilateral or bilateral pathology and size of perforation were not determinants of surgical success. Conclusion: Tympanoplasty performed by residents of the second year of residence showed satisfactory results regarding both surgical audiometric.

  8. Surgical Treatment of Acute Pancreatitis.

    Science.gov (United States)

    Werner, Jens; Uhl, Waldemar; Büchler, Markus W.

    2003-10-01

    Patients with predicted severe necrotizing pancreatitis as diagnosed by C-reactive protein (>150 mg/L) and/or contrast-enhanced computed tomography should be managed in the intensive care unit. Prophylactic broad-spectrum antibiotics reduce infection rates and survival in severe necrotizing pancreatitis. Endoscopic retrograde cholangiopancreatography and endoscopic sphincterotomy is a causative therapy for gallstone pancreatitis with impacted stones, biliary sepsis, or obstructive jaundice. Fine needle aspiration for bacteriology should be performed to differentiate between sterile and infected pancreatic necrosis in patients with sepsis syndrome. Infected pancreatic necrosis in patients with clinical signs and symptoms of sepsis is an indication for surgery. Patients with sterile pancreatic necrosis should be managed conservatively. Surgery in patients with sterile necrosis may be indicated in cases of persistent necrotizing pancreatitis and in the rare cases of "fulminant acute pancreatitis." Early surgery, within 14 days after onset of the disease, is not recommended in patients with necrotizing pancreatitis. The surgical approach should be organ-preserving (debridement/necrosectomy) and combined with a postoperative management concept that maximizes postoperative evacuation of retroperitoneal debris and exudate. Minimally invasive surgical procedures have to be regarded as an experimental approach and should be restricted to controlled trials. Cholecystectomy should be performed to avoid recurrence of gallstone-associated acute pancreatitis.

  9. Cardiothoracic surgical experience in Ghana.

    Science.gov (United States)

    Tettey, Mark; Tamatey, Martin; Edwin, Frank

    2016-10-01

    Ghana is one of the few low-to-middle-income countries in sub-Saharan Africa able to consistently sustain a cardiothoracic program with locally trained staff for more than two decades. Cardiothoracic surgery practice in Ghana started in 1964 but faltered from a combination of political and the economic problems. In 1989, Dr. Kwabena Frimpong-Boateng, a Ghanaian cardiothoracic surgeon trained in Hannover, rekindled interest in cardiothoracic surgery and in establishing a National Cardiothoracic Centre. His vision and leadership has brought cardiothoracic surgery practice in Ghana to its current high level. As a result, the medical landscape of what is achievable locally in both pediatric and adult patients has changed substantially: outbound medical travel that used to be common among Ghanaian cardiovascular patients has been reduced drastically. Ghana's National Cardiothoracic Center (NCTC), the only tertiary center in the country for cardiothoracic surgical pathology manages all such patients that were previously referred abroad. The NCTC has become a medical/surgical hub in the West African sub-region providing service, training, and research opportunities to neighboring countries. The Centre is accredited by the West African College of Surgeons as a center of excellence for training specialists in cardiothoracic surgery. Expectedly, practicing cardiothoracic surgery in such a resource-poor setting has peculiar challenges. This review focuses on the history, practice, successes, and challenges of cardiovascular and thoracic surgery in Ghana.

  10. Informed consent in surgical trials.

    Science.gov (United States)

    Etchells, E

    1999-12-01

    All participants must provide a valid consent to surgical clinical trials. A valid consent requires patient capacity, adequate disclosure of information, and voluntariness. Capacity is the ability to understand information relevant to making a decision and to appreciate the reasonably foreseeable consequences of a decision or lack of decision. To protect vulnerable persons, an incapable person should not be enrolled in most clinical trials. The only exception is if the study can only be conducted on incapable persons. If the willing research participant is incapable, consent must be obtained from others through a process called substitute (or proxy) consent. Disclosure refers to the provision of relevant information to the patient and its comprehension by the patient. Most surgical trials carry more than minimal risks, so the requirement for careful disclosure of these risks to potential participants is generally stringent. Voluntariness refers to the freedom of a person to make a treatment decision. In specific circumstances related to emergency research, the requirement for consent may be waived. Waiver can be justified only if the delay required to obtain consent would prevent the research from occurring and only after prior consultation with from the "community" of potential research participants.

  11. Surgical infections: a microbiological study

    Directory of Open Access Journals (Sweden)

    Santosh Saini

    Full Text Available Surgical infections are mostly polymicrobial, involving both aerobes and anaerobes. One hundred seventeen cases comprised of abscesses (n=51, secondary peritonitis (n=25, necrotizing fascitis (n=22 and wounds with devitalized tissues (n=19 were studied. The number of microorganisms isolated per lesion was highest in secondary peritonitis (2.32. The aerobe/ anaerobe ratio was 0.81 in secondary peritonitis and 1.8 in necrotizing fascitis. Most secondary peritonitis (80%, necrotizing fascitis (75% and wounds with devitalized tissues (66.7% were polymicrobial. Common microorganisms isolated in our study were E. coli, Staphylococcus aureus, Klebsiella spp., Pseudomonas aeruginosa, Bacteroides fragilis and Peptostreptococcus spp. The most effective antibiotics for S. aureus were clindamycin (79.1% and cefuroxime (70.8%. For Gram-negatives (Klebsiella spp., E. coli and Proteus spp., the most effective antibiotics were cefotaxime, ceftizoxime, amikacin and ciprofloxacin. Pseudomonas aeruginosa was maximally sensitive to amikacin (35.2% and ciprofloxacin (35.2%. The greatest degree of multidrug resistance to all the drugs was found in P. aeruginosa (52.9%, followed by Klebsiella spp. (33.3%, Proteus spp. (33.3%, E. coli (22.2%, and S. aureus (12.5%. All the anaerobes that we isolated were 100% sensitive to metronidazole and chloramphenicol, followed by clindamycin (95% to 100%. Apart from antibiotic therapy, non-antimicrobial methods, such as hyperbaric oxygen therapy and debridement also play an important role in the treatment of surgical infections.

  12. Membranes, methods of making membranes, and methods of separating gases using membranes

    Science.gov (United States)

    Ho, W. S. Winston

    2012-10-02

    Membranes, methods of making membranes, and methods of separating gases using membranes are provided. The membranes can include at least one hydrophilic polymer, at least one cross-linking agent, at least one base, and at least one amino compound. The methods of separating gases using membranes can include contacting a gas stream containing at least one of CO.sub.2, H.sub.2S, and HCl with one side of a nonporous and at least one of CO.sub.2, H.sub.2S, and HCl selectively permeable membrane such that at least one of CO.sub.2, H.sub.2S, and HCl is selectively transported through the membrane.

  13. Polyazole hollow fiber membranes for direct contact membrane distillation

    KAUST Repository

    Maab, Husnul; Alsaadi, Ahmad Salem; Francis, Lijo; Livazovic, Sara; Ghaffour, NorEddine; Amy, Gary L.; Nunes, Suzana Pereira

    2013-01-01

    Porous hollow fiber membranes were fabricated from fluorinated polyoxadiazole and polytriazole by a dry-wet spinning method for application in desalination of Red Sea water by direct contact membrane distillation (DCMD). The data were compared with commercially available hollow fiber MD membranes prepared from poly(vinylidene fluoride). The membranes were characterized by electron microscopy, liquid entry pressure (LEP), and pore diameter measurements. Finally, the hollow fiber membranes were tested for DCMD. Salt selectivity as high as 99.95% and water fluxes as high as 35 and 41 L m -2 h-1 were demonstrated, respectively, for polyoxadiazole and polytriazole hollow fiber membranes, operating at 80 C feed temperature and 20 C permeate. © 2013 American Chemical Society.

  14. Polyazole hollow fiber membranes for direct contact membrane distillation

    KAUST Repository

    Maab, Husnul

    2013-08-07

    Porous hollow fiber membranes were fabricated from fluorinated polyoxadiazole and polytriazole by a dry-wet spinning method for application in desalination of Red Sea water by direct contact membrane distillation (DCMD). The data were compared with commercially available hollow fiber MD membranes prepared from poly(vinylidene fluoride). The membranes were characterized by electron microscopy, liquid entry pressure (LEP), and pore diameter measurements. Finally, the hollow fiber membranes were tested for DCMD. Salt selectivity as high as 99.95% and water fluxes as high as 35 and 41 L m -2 h-1 were demonstrated, respectively, for polyoxadiazole and polytriazole hollow fiber membranes, operating at 80 C feed temperature and 20 C permeate. © 2013 American Chemical Society.

  15. Chemical degradation mechanisms of membranes for alkaline membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Choe, Yoong-Kee [National Institute of Advanced Industrial Science and Technology, Umezono 1-1-1, Tsukuba (Japan); Henson, Neil J.; Kim, Yu Seung [Los Alamos National Laboratory, Los Alamos, NM (United States)

    2015-12-31

    Chemical degradation mechanisms of membranes for alkaline membrane fuel cells have been investigated using density functional theory (DFT). We have elucidated that the aryl-ether moiety of membranes is one of the weakest site against attack of hydroxide ions. The results of DFT calculations for hydroxide initiated aryl-ether cleavage indicated that the aryl-ether cleavage occurred prior to degradation of cationic functional group. Such a weak nature of the aryl-ether group arises from the electron deficiency of the aryl group as well as the low bond dissociation energy. The DFT results suggests that removal of the aryl-ether group in the membrane should enhance the stability of membranes under alkaline conditions. In fact, an ether fee poly(phenylene) membrane exhibits excellent stability against the attack from hydroxide ions.

  16. Pediatric surgical diseases. A radiological surgical case study approach

    International Nuclear Information System (INIS)

    Esposito, Ciro; Esposito, Giovanni

    2009-01-01

    Radiologic evaluation of an infant or child suspected of having a surgical disease can be a complex problem. With this volume, the editors have created a book focused on pediatric imaging written by pediatricians, pediatric surgeons and pediatric radiologists. This book is a collection of over 200 case reports. The concept is a case study approach: The reader is given radiologic images (plain radiography, computed tomography, magnetic resonance imaging, ultrasonography, etc.) and the clinical history of the patient. On the basis of this information, the reader is asked to identify a diagnostic and therapeutic strategy. Each case is complemented by information on the disease affecting the patient and the management of the case shown, including therapy and follow-up. This educational text is targeted at all medical professionals faced with a variety of diagnostic and therapeutic problems affecting infants and children. (orig.)

  17. Pediatric surgical diseases. A radiological surgical case study approach

    Energy Technology Data Exchange (ETDEWEB)

    Esposito, Ciro [Federico II Univ. of Naples (Italy). Chair of Pediatric Surgery; Esposito, Giovanni (eds.) [Federico II Univ. of Naples (Italy). School of Medicine

    2009-07-01

    Radiologic evaluation of an infant or child suspected of having a surgical disease can be a complex problem. With this volume, the editors have created a book focused on pediatric imaging written by pediatricians, pediatric surgeons and pediatric radiologists. This book is a collection of over 200 case reports. The concept is a case study approach: The reader is given radiologic images (plain radiography, computed tomography, magnetic resonance imaging, ultrasonography, etc.) and the clinical history of the patient. On the basis of this information, the reader is asked to identify a diagnostic and therapeutic strategy. Each case is complemented by information on the disease affecting the patient and the management of the case shown, including therapy and follow-up. This educational text is targeted at all medical professionals faced with a variety of diagnostic and therapeutic problems affecting infants and children. (orig.)

  18. Posterior atlanto-occipital and atlanto-axial area and its surgical interest

    Directory of Open Access Journals (Sweden)

    Newton José Godoy Pimenta

    2014-10-01

    Full Text Available Classic anatomical studies describe two membranes – atlanto-occipital and atlanto-axial in the posterior aspect of the craniocervical region. During many surgical procedures in this area, however, we have not found such membranes. Objective To clarify the anatomical aspects and structures taking part of the posterior atlanto-occipital and atlanto-axial area. Method Analysis of histological cuts of three human fetuses and anatomical studies of 8 adult human cadavers. Results In both atlanto-occipital and atlanto-axial areas, we have observed attachment between suboccipital deep muscles and the spinal cervical dura. However, anatomical description of such attachments could not be found in textbooks of anatomy. Conclusion Our study shows the absence of the classical atlanto-occipital and atlanto-axial membranes; the occipito-C1 and C1-C2 posterior intervals are an open area, allowing aponeurotic attachment among cervical dura mater and posterior cervical muscles.

  19. Amodiaquine polymeric membrane electrode.

    Science.gov (United States)

    Malongo, T Kimbeni; Blankert, B; Kambu, O; Amighi, K; Nsangu, J; Kauffmann, J-M

    2006-04-11

    The construction and electrochemical response characteristics of two types of poly(vinyl chloride) (PVC) membrane sensors for the determination of amodiaquine hydrochloride (ADQ.2HCl) are described. The sensing membrane comprised an ion-pair formed between the cationic drug and sodium tetraphenyl borate (NaTPB) or potassium tetrakis(4-chlorophenyl) borate (KTCPB) in a plasticized PVC matrix. Eight PVC membrane ion-selective electrodes were fabricated and studied. Several plasticizers were studied namely, dioctyl phthalate (DOP), 2-nitrophenyl octyl ether (NPOE), dioctyl phenylphosphonate (DOPP) and bis(2-ethylhexyl)adipate (EHA). The sensors display a fast, stable and near-Nernstian response over a relative wide ADQ concentration range (3.2 x 10(-6) to 2.0 x 10(-2) M), with slopes comprised between 28.5 and 31.4 mV dec(-1) in a pH range comprised between pH 3.7 and 5.5. The assay of amodiaquine hydrochloride in pharmaceutical dosage forms using one of the proposed sensors gave average recoveries of 104.3 and 99.9 with R.S.D. of 0.3 and 0.6% for tablets (Malaritab) and a reconstituted powder containing ADQ.2HCl, respectively. The sensor was also used for dissolution profile studies of two drug formulations. The sensor proved to have a good selectivity for ADQ.2HCl over some inorganic and organic compounds, however, berberine chloride interfered significantly. The results were validated by comparison with a spectrophotometric assay according to the USP pharmacopoeia.

  20. Introducing Membrane Charge and Membrane Potential to T Cell Signaling

    Directory of Open Access Journals (Sweden)

    Yuanqing Ma

    2017-11-01

    Full Text Available While membrane models now include the heterogeneous distribution of lipids, the impact of membrane charges on regulating the association of proteins with the plasma membrane is often overlooked. Charged lipids are asymmetrically distributed between the two leaflets of the plasma membrane, resulting in the inner leaflet being negatively charged and a surface potential that attracts and binds positively charged ions, proteins, and peptide motifs. These interactions not only create a transmembrane potential but they can also facilitate the formation of charged membrane domains. Here, we reference fields outside of immunology in which consequences of membrane charge are better characterized to highlight important mechanisms. We then focus on T cell receptor (TCR signaling, reviewing the evidence that membrane charges and membrane-associated calcium regulate phosphorylation of the TCR–CD3 complex and discuss how the immunological synapse exhibits distinct patterns of membrane charge distribution. We propose that charged lipids, ions in solution, and transient protein interactions form a dynamic equilibrium during T cell activation.

  1. Oxygen Transport Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay

    2008-08-30

    The focus of this research was to develop new membrane materials by synthesizing different compounds and determining their defect structures, crystallographic structures and electrical properties. In addition to measuring electrical conductivity, oxygen vacancy concentration was also evaluated using thermogravimetry, Neutron diffraction and Moessbauer Spectroscopy. The reducing conditions (CO{sub 2}/CO/H{sub 2} gas mixtures with steam) as encountered in a reactor environment can be expected to have significant influence on the mechanical properties of the oxides membranes. Various La based materials with and without Ti were selected as candidate membrane materials for OTM. The maximum electrical conductivity of LSF in air as a function of temperature was achieved at < 600 C and depends on the concentration of Sr (acceptor dopant). Oxygen occupancy in LSF was estimated using Neutron diffractometry and Moessbauer Spectroscopy by measuring magnetic moment changes depending on the Fe{sup 3+} and Fe{sup 4+} ratio. After extensive studies of candidate materials, lanthanum ferrites (LSF and LSFT) were selected as the favored materials for the oxygen transport membrane (OTM). LSF is a very good material for an OTM because of its high electronic and oxygen ionic conductivity if long term stability and mechanical strength are improved. LSFT not only exhibits p-type behavior in the high oxygen activity regime, but also has n-type conduction in reducing atmospheres. Higher concentrations of oxygen vacancies in the low oxygen activity regime may improve the performance of LSFT as an OTM. The hole concentration is related to the difference in the acceptor and donor concentration by the relation p = [Sr'{sub La}]-[Ti{sm_bullet}{sub Fe}]. The chemical formulation predicts that the hole concentration is, p = 0.8-0.45 or 0.35. Experimental measurements indicated that p is about {approx} 0.35. The activation energy of conduction is 0.2 eV which implies that LSCF conducts via the

  2. Molecularly Imprinted Membranes

    Science.gov (United States)

    Trotta, Francesco; Biasizzo, Miriam; Caldera, Fabrizio

    2012-01-01

    Although the roots of molecularly imprinted polymers lie in the beginning of 1930s in the past century, they have had an exponential growth only 40–50 years later by the works of Wulff and especially by Mosbach. More recently, it was also proved that molecular imprinted membranes (i.e., polymer thin films) that show recognition properties at molecular level of the template molecule are used in their formation. Different procedures and potential application in separation processes and catalysis are reported. The influences of different parameters on the discrimination abilities are also discussed. PMID:24958291

  3. Choroidal neovascular membrane

    Directory of Open Access Journals (Sweden)

    Bhatt Nitul

    1998-01-01

    Full Text Available Choroidal neovascular membrane in the macular area is one of the leading causes of severe visual loss. Usually a manifestation in elderly population, it is often associated with age-related macular degeneration. The current mainstay of management is early diagnosis, usually by fundus examination, aided by angiography and photocoagulation in selected cases. Various other modalities of treatment including surgery are being considered as alternate options, but with limited success. The purpose of this review is to briefly outline the current concepts and the management strategy from a clinician′s viewpoint.

  4. Choroidal neovascular membrane.

    Science.gov (United States)

    Bhatt, N S; Diamond, J G; Jalali, S; Das, T

    1998-06-01

    Choroidal neovascular membrane in the macular area is one of the leading causes of severe visual loss. Usually a manifestation in elderly population, it is often associated with age-related macular degeneration. The current mainstay of management is early diagnosis, usually by fundus examination, aided by angiography and photocoagulation in selected cases. Various other modalities of treatment including surgery are being considered as alternate options, but with limited success. The purpose of this review is to briefly outline the current concepts and the management strategy from a clinician's viewpoint.

  5. Novicidin interactions with phospholipid membranes

    DEFF Research Database (Denmark)

    Balakrishnan, Vijay Shankar

    Antimicrobial peptides target bacterial cell membranes and are considered as potential antibiotics. Their interactions with cell membranes are studied using different approaches. This thesis comprises of the biophysical investigations on the antimicrobial peptide Novicidin, interacting with lipos......Antimicrobial peptides target bacterial cell membranes and are considered as potential antibiotics. Their interactions with cell membranes are studied using different approaches. This thesis comprises of the biophysical investigations on the antimicrobial peptide Novicidin, interacting...... with liposomes. The lipid-induced changes in the peptide due to membrane binding, and the peptide-induced changes in the membrane properties were investigated using various spectroscopic and calorimetric methods, and the structural and thermodynamic aspects of peptide-lipid interactions are discussed. This helps...

  6. Mathematical modelling of membrane separation

    DEFF Research Database (Denmark)

    Vinther, Frank

    This thesis concerns mathematical modelling of membrane separation. The thesis consists of introductory theory on membrane separation, equations of motion, and properties of dextran, which will be the solute species throughout the thesis. Furthermore, the thesis consist of three separate mathemat......This thesis concerns mathematical modelling of membrane separation. The thesis consists of introductory theory on membrane separation, equations of motion, and properties of dextran, which will be the solute species throughout the thesis. Furthermore, the thesis consist of three separate...... mathematical models, each with a different approach to membrane separation. The first model is a statistical model investigating the interplay between solute shape and the probability of entering the membrane. More specific the transition of solute particles from being spherical to becoming more elongated...

  7. New multimedia advances in surgical information.

    Science.gov (United States)

    Glenn, Ian C; Abdulhai, Sophia; Lamoshi, Abdulraouf; Ponsky, Todd A

    2018-06-01

    When discussing new trends in pediatric surgery, the tendency is to focus on novel surgical technology and techniques. However, it is equally important to examine how the practicing surgeon stays abreast in an ever-changing field. This article serves as a brief guide to the future of surgical education for the attending surgeon. Broadly, advances in surgical education consist of new methods of filtration and delivery of knowledge.

  8. Radiation effects on cell membranes

    International Nuclear Information System (INIS)

    Koeteles, G.J.

    1982-01-01

    Experimental data are presented concerning the effects of relatively low doses of x radiation and low concentration of tritiated water (HTO) on various receptor functions - concanavalin A, cationized ferritin, poliovirus of plasma membranes of animal and human cells which point to early and temporary disturbances of the composite structures and functions of membranes. References are given to the manifold influence of radiation-induced membrane phenomenon on the development and regeneration of radiation injuries. (author)

  9. Decrumpling membranes by quantum effects

    Science.gov (United States)

    Borelli, M. E. S.; Kleinert, H.

    2001-02-01

    The phase diagram of an incompressible fluid membrane subject to quantum and thermal fluctuations is calculated exactly in a large number of dimensions of configuration space. At zero temperature, a crumpling transition is found at a critical bending rigidity 1/αc. For membranes of fixed lateral size, a crumpling transition occurs at nonzero temperatures in an auxiliary mean field approximation. As the lateral size L of the membrane becomes large, the flat regime shrinks with 1/ln L.

  10. Surgical management of nasal obstruction.

    Science.gov (United States)

    Moche, Jason A; Palmer, Orville

    2012-05-01

    The proper evaluation of the patient with nasal obstruction relies on a comprehensive history and physical examination. Once the site of obstruction is accurately identified, the patient may benefit from a trial of medical management. At times however, the definitive treatment of nasal obstruction relies on surgical management. Recognizing the nasal septum, nasal valve, and turbinates as possible sites of obstruction and addressing them accordingly can dramatically improve a patient's nasal breathing. Conservative resection of septal cartilage, submucous reduction of the inferior turbinate, and structural grafting of the nasal valve when appropriate will provide the optimal improvement in nasal airflow and allow for the most stable results. Copyright © 2012. Published by Elsevier Inc.

  11. [Surgical laboratory in pregraduate medicine.

    Science.gov (United States)

    Tapia-Jurado, Jesús

    2011-01-01

    Surgical laboratory in pregraduate students in medicine is beneficial and improves learning processes in cognitive aspects and skills acquisition. It is also an early initiation into scientific research. The laboratory is the introductory pathway into basic concepts of medical science (meaningful learning). It is also where students gain knowledge in procedures and abilities to obtain professional skills, an interactive teacher-student process. Medicine works rapidly to change from an art to a science. This fact compromises all schools and medical faculties to analyze their actual lesson plans. Simulators give students confidence and ability and save time, money and resources, eliminating at the same time the ethical factor of using live animals and the fear of patient safety. Multimedia programs may give a cognitive context evolving logically with an explanation based on written and visual animation followed by a clinical problem and its demonstration in a simulator, all before applying knowledge to the patient.

  12. Surgical Management of Enterocutaneous Fistula

    International Nuclear Information System (INIS)

    Lee, Suk Hwan

    2012-01-01

    Enterocutaneous (EC) fistula is an abnormal connection between the gastrointestinal (GI) tract and skin. The majority of EC fistulas result from surgery. About one third of fistulas close spontaneously with medical treatment and radiologic interventions. Surgical treatment should be reserved for use after sufficient time has passed from the previous laparotomy to allow lysis of the fibrous adhesion using full nutritional and medical treatment and until a complete understanding of the anatomy of the fistula has been achieved. The successful management of GI fistula requires a multi-disciplinary team approach including a gastroenterologist, interventional radiologist, enterostomal therapist, dietician, social worker and surgeons. With this coordinated approach, EC fistula can be controlled with acceptable morbidity and mortality.

  13. Surgical managements of radiation enteritis

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Tsuguo; Naito, Kazuyo; Noomi, Shinppachiro; Kurioka, Hideaki; Yamagishi, Hisakazu (Kyoto Prefectural Univ. of Medicine (Japan))

    1983-02-01

    Radiation injury to the digestive tract was surgically treated in 22 cases. Six of them died shortly after surgery. Major symptoms were ileus or perforative peritonitis in 20 of the 22 cases, and surgery was performed for ileal lesion in 18 cases, indicating the significance of lesions in the small intestine. Seven patients underwent resection of the injured portion of the intestinal tract and anastomotic reconstruction in one stage, but 3 of them died from rupture of sutures. It was highly probable that anastomosis was made using an injured portion of the intestine. Intraoperative judgement of intestinal injury is made by palpation and inspection. If judgement is difficult, an artificial anus should be constructed first, and anastomotic reconstruction should be done in the 2nd stage. Since delayed injury of this disease is an ischemic change due to vascular obliteration, conservative therapy never leads to complete recovery, but active resection and anastomosis seem to produce a satisfactory result.

  14. Surgical managements of radiation enteritis

    International Nuclear Information System (INIS)

    Tanaka, Tsuguo; Naito, Kazuyo; Noomi, Shinppachiro; Kurioka, Hideaki; Yamagishi, Hisakazu

    1983-01-01

    Radiation injury to the digestive tract was surgically treated in 22 cases. Six of them died shortly after surgery. Major symptoms were ileus or perforative peritonitis in 20 of the 22 cases, and surgery was performed for ileal lesion in 18 cases, indicating the significance of lesions in the small intestine. Seven patients underwent resection of the injured portion of the intestinal tract and anastomotic reconstruction in one stage, but 3 of them died from rupture of sutures. It was highly probable that anastomosis was made using an injured portion of the intestine. Intraoperative judgement of intestinal injury is made by palpation and inspection. If judgement is difficult, an artificial anus should be constructed first, and anastomotic reconstruction should be done in the 2nd stage. Since delayed injury of this disease is an ischemic change due to vascular obliteration, conservative therapy never leads to complete recovery, but active resection and anastomosis seem to produce a satisfactory result. (Chiba, N.)

  15. Virtual reality in surgical training.

    Science.gov (United States)

    Lange, T; Indelicato, D J; Rosen, J M

    2000-01-01

    Virtual reality in surgery and, more specifically, in surgical training, faces a number of challenges in the future. These challenges are building realistic models of the human body, creating interface tools to view, hear, touch, feel, and manipulate these human body models, and integrating virtual reality systems into medical education and treatment. A final system would encompass simulators specifically for surgery, performance machines, telemedicine, and telesurgery. Each of these areas will need significant improvement for virtual reality to impact medicine successfully in the next century. This article gives an overview of, and the challenges faced by, current systems in the fast-changing field of virtual reality technology, and provides a set of specific milestones for a truly realistic virtual human body.

  16. Evolving Educational Techniques in Surgical Training.

    Science.gov (United States)

    Evans, Charity H; Schenarts, Kimberly D

    2016-02-01

    Training competent and professional surgeons efficiently and effectively requires innovation and modernization of educational methods. Today's medical learner is quite adept at using multiple platforms to gain information, providing surgical educators with numerous innovative avenues to promote learning. With the growth of technology, and the restriction of work hours in surgical education, there has been an increase in use of simulation, including virtual reality, robotics, telemedicine, and gaming. The use of simulation has shifted the learning of basic surgical skills to the laboratory, reserving limited time in the operating room for the acquisition of complex surgical skills". Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Epiretinal membrane surgery

    DEFF Research Database (Denmark)

    Hamoudi, Hassan; Correll Christensen, Ulrik; La Cour, Morten

    2017-01-01

    Purpose: To assess the impact of combined phacoemulsification-vitrectomy and sequential surgery for idiopathic epiretinal membrane (ERM) on refractive error (RE) and macular morphology. Methods: In this prospective clinical trial, we allocated phakic eyes with ERM to (1) cataract surgery and subs......Purpose: To assess the impact of combined phacoemulsification-vitrectomy and sequential surgery for idiopathic epiretinal membrane (ERM) on refractive error (RE) and macular morphology. Methods: In this prospective clinical trial, we allocated phakic eyes with ERM to (1) cataract surgery...... and achieved spherical equivalent); secondary outcomes were best-corrected visual acuity (BCVA), and incidence of cystoid macular oedema (CME) defined as >10% increment of central subfield macular thickness (CSMT). Results: Sixty-two eyes were enrolled. The mean RE showed a small myopic shift of -0.36D in all...... between the groups. Four cases (17%) in the CAT group had resolved visual complaints and improved BCVA after cataract surgery resulting in no need for PPV within the follow-up period. Conclusion: Surgery for idiopathic ERM in phakic eyes with either phaco-vitrectomy or sequential surgery are equal...

  18. Current-Induced Membrane Discharge

    DEFF Research Database (Denmark)

    Andersen, Mathias Bækbo; van Soestbergen, M.; Mani, A.

    2012-01-01

    . Salt depletion leads to a large electric field resulting in a local pH shift within the membrane with the effect that the membrane discharges and loses its ion selectivity. Since salt co-ions, H+ ions, and OH- ions contribute to OLC, CIMD interferes with electrodialysis (salt counterion removal...... neglects chemical effects and remains to be quantitatively tested. Here, we show that charge regulation and water self-ionization can lead to OLC by "current-induced membrane discharge'' (CIMD), even in the absence of fluid flow, in ion-exchange membranes much thicker than the local Debye screening length...

  19. Track membranes, production, properties, applications

    International Nuclear Information System (INIS)

    Oganesjan, Yu.Ts.

    1994-01-01

    The problems of producing track membranes on heavy ion beams of the Flerov Laboratory are considered. The parameters of the running accelerators and equipment for the irradiation of polymer foils are presented. The process of production of track membranes based on different polymeric materials and various applications of the membranes are described. Special attention is given to the principally new applications and devices developed at the Laboratory. This report presents the results obtained by a big group of scientists and engineers working in the field of elaboration, investigation and application of track membranes (author). 21 refs, 20 figs, 1 tab

  20. Functional microdomains in bacterial membranes.

    Science.gov (United States)

    López, Daniel; Kolter, Roberto

    2010-09-01

    The membranes of eukaryotic cells harbor microdomains known as lipid rafts that contain a variety of signaling and transport proteins. Here we show that bacterial membranes contain microdomains functionally similar to those of eukaryotic cells. These membrane microdomains from diverse bacteria harbor homologs of Flotillin-1, a eukaryotic protein found exclusively in lipid rafts, along with proteins involved in signaling and transport. Inhibition of lipid raft formation through the action of zaragozic acid--a known inhibitor of squalene synthases--impaired biofilm formation and protein secretion but not cell viability. The orchestration of physiological processes in microdomains may be a more widespread feature of membranes than previously appreciated.

  1. Permeability testing of biomaterial membranes

    Energy Technology Data Exchange (ETDEWEB)

    Dreesmann, L; Hajosch, R; Nuernberger, J Vaz; Schlosshauer, B [NMI Natural and Medical Sciences Institute at University Tuebingen, Markwiesenstr. 55, D-72770 Reutlingen (Germany); Ahlers, M [GELITA AG, Gammelsbacher Str. 2, D-69412 Eberbach (Germany)], E-mail: schlosshauer@nmi.de

    2008-09-01

    The permeability characteristics of biomaterials are critical parameters for a variety of implants. To analyse the permeability of membranes made from crosslinked ultrathin gelatin membranes and the transmigration of cells across the membranes, we combined three technical approaches: (1) a two-chamber-based permeability assay, (2) cell culturing with cytochemical analysis and (3) biochemical enzyme electrophoresis (zymography). Based on the diffusion of a coloured marker molecule in conjunction with photometric quantification, permeability data for a gelatin membrane were determined in the presence or absence of gelatin degrading fibroblasts. Cytochemical evaluation after cryosectioning of the membranes was used to ascertain whether fibroblasts had infiltrated the membrane inside. Zymography was used to investigate the potential release of proteases from fibroblasts, which are known to degrade collagen derivatives such as gelatin. Our data show that the diffusion equilibrium of a low molecular weight dye across the selected gelatin membrane is approached after about 6-8 h. Fibroblasts increase the permeability due to cavity formation in the membrane inside without penetrating the membrane for an extended time period (>21 days in vitro). Zymography indicates that cavity formation is most likely due to the secretion of matrix metalloproteinases. In summary, the combination of the depicted methods promises to facilitate a more rational development of biomaterials, because it provides a rapid means of determining permeability characteristics and bridges the gap between descriptive methodology and the mechanistic understanding of permeability alterations due to biological degradation.

  2. Permeability testing of biomaterial membranes

    International Nuclear Information System (INIS)

    Dreesmann, L; Hajosch, R; Nuernberger, J Vaz; Schlosshauer, B; Ahlers, M

    2008-01-01

    The permeability characteristics of biomaterials are critical parameters for a variety of implants. To analyse the permeability of membranes made from crosslinked ultrathin gelatin membranes and the transmigration of cells across the membranes, we combined three technical approaches: (1) a two-chamber-based permeability assay, (2) cell culturing with cytochemical analysis and (3) biochemical enzyme electrophoresis (zymography). Based on the diffusion of a coloured marker molecule in conjunction with photometric quantification, permeability data for a gelatin membrane were determined in the presence or absence of gelatin degrading fibroblasts. Cytochemical evaluation after cryosectioning of the membranes was used to ascertain whether fibroblasts had infiltrated the membrane inside. Zymography was used to investigate the potential release of proteases from fibroblasts, which are known to degrade collagen derivatives such as gelatin. Our data show that the diffusion equilibrium of a low molecular weight dye across the selected gelatin membrane is approached after about 6-8 h. Fibroblasts increase the permeability due to cavity formation in the membrane inside without penetrating the membrane for an extended time period (>21 days in vitro). Zymography indicates that cavity formation is most likely due to the secretion of matrix metalloproteinases. In summary, the combination of the depicted methods promises to facilitate a more rational development of biomaterials, because it provides a rapid means of determining permeability characteristics and bridges the gap between descriptive methodology and the mechanistic understanding of permeability alterations due to biological degradation

  3. Proton exchange membrane fuel cells

    CERN Document Server

    Qi, Zhigang

    2013-01-01

    Preface Proton Exchange Membrane Fuel CellsFuel CellsTypes of Fuel CellsAdvantages of Fuel CellsProton Exchange Membrane Fuel CellsMembraneCatalystCatalyst LayerGas Diffusion MediumMicroporous LayerMembrane Electrode AssemblyPlateSingle CellStackSystemCell Voltage Monitoring Module (CVM)Fuel Supply Module (FSM)Air Supply Module (ASM)Exhaust Management Module (EMM)Heat Management Module (HMM)Water Management Module (WMM)Internal Power Supply Module (IPM)Power Conditioning Module (PCM)Communications Module (COM)Controls Module (CM)SummaryThermodynamics and KineticsTheoretical EfficiencyVoltagePo

  4. Composite membrane with integral rim

    Science.gov (United States)

    Routkevitch, Dmitri; Polyakov, Oleg G

    2015-01-27

    Composite membranes that are adapted for separation, purification, filtration, analysis, reaction and sensing. The composite membranes can include a porous support structure having elongate pore channels extending through the support structure. The composite membrane also includes an active layer comprising an active layer material, where the active layer material is completely disposed within the pore channels between the surfaces of the support structure. The active layer is intimately integrated within the support structure, thus enabling great robustness, reliability, resistance to mechanical stress and thermal cycling, and high selectivity. Methods for the fabrication of composite membranes are also provided.

  5. Mechanics of Lipid Bilayer Membranes

    Science.gov (United States)

    Powers, Thomas R.

    All cells have membranes. The plasma membrane encapsulates the cell's interior, acting as a barrier against the outside world. In cells with nuclei (eukaryotic cells), membranes also form internal compartments (organelles) which carry out specialized tasks, such as protein modification and sorting in the case of the Golgi apparatus, and ATP production in the case of mitochondria. The main components of membranes are lipids and proteins. The proteins can be channels, carriers, receptors, catalysts, signaling molecules, or structural elements, and typically contribute a substantial fraction of the total membrane dry weight. The equilibrium properties of pure lipid membranes are relatively well-understood, and will be the main focus of this article. The framework of elasticity theory and statistical mechanics that we will develop will serve as the foundation for understanding biological phenomena such as the nonequilibrium behavior of membranes laden with ion pumps, the role of membrane elasticity in ion channel gating, and the dynamics of vesicle fission and fusion. Understanding the mechanics of lipid membranes is also important for drug encapsulation and delivery.

  6. Amniotic membrane for burn trauma

    International Nuclear Information System (INIS)

    Jamaluddin Zainol; Hasim Mohammad

    1999-01-01

    Amniotic membranes are derived from human placentae at birth. They have two layers mainly the amniotic and the chorionic surfaces which are separated by a thin layer of connective tissues. The two layers are separated during procurement, the placenta and the chorionic side are discarded and the amnion membranes are then further processed. Amnion membranes are normally procured from placentae which are normally free of infections, i.e; the mothers are antenatally screened for sexually transmitted diseases or AlDs related diseases. Intrapartum the mother should not be having chorioamnionitis or jaundice. Sometimes the amniotic membranes are acquired from fresh elective caeserian sections. After processing, the amniotic membranes are packed in two layers of polypropylene and radiated with cobalt 60 at a dose of about 25 kGy. The amniotic membranes are clinically used to cover burn surfaces especially effective for superficial or partial thickness burns. The thin membranes adhered well to the trauma areas and peeled off automatically by the second week. No change of dressing were necessary during these times because of the close adherence, there were less chance of external contamination or infections of these wounds. Due to their flexibility they are very useful to cover difference contours of the human body for example the face, body, elbows or knees. However our experience revealed that amniotic membranes are not useful for third degree bums because the membranes dissolves by the enzymes present in the wounds

  7. Surgical management of the newborn with congenital diaphragmatic hernia.

    Science.gov (United States)

    Tsao, Kuojen; Lally, Kevin P

    2011-01-01

    Despite advances in the surgical treatment and medical management over the last 20 years, neonates with congenital diaphragmatic hernia (CDH) remain one of the most challenging patient groups for all clinicians. Treatment strategies have shifted from emergent surgical repair and maximum ventilatory support to delayed repair and preoperative hemodynamic stabilization with lung-sparing ventilation strategies and extracorporeal membrane oxygenation. Subsequently, overall survival has improved to as high as 80% in some centers. However, specific treatment criteria are vague and highly variable amongst centers. This lack of consensus of these treatment modalities remains elusive due to the heterogeneity in disease severity as well as heterogeneity in patient care amongst centers. As a result of the rare incidence of disease and limited experience of individual centers, the evidence for CDH is typically reported as a homogenous disease largely supported by case series and networked-based studies. To better evaluate the data and compare treatment strategies, a classification and stratification of disease and centers is needed. Copyright © 2010 S. Karger AG, Basel.

  8. Surgical outcomes of early congenital cholesteatoma: minimally invasive transcanal approach.

    Science.gov (United States)

    Lee, Sang H; Jang, Jeong H; Lee, Dongjun; Lee, Hye-Ryung; Lee, Kyu-Yup

    2014-03-01

    To introduce a simple and alternative surgical technique, minimally invasive transcanal myringotomy (MITM), for early stage congenital cholesteatoma in children and to evaluate the feasibility and results of MITM for management of early stage congenital cholesteatoma with respect to its effectiveness and safety. Retrospective review. Between August 2008 and September 2012, a total of 36 patients with congenital cholesteatoma met the inclusion criteria and were analyzed. Patient medical records, including demographic characteristics, intraoperative findings, and follow-up records, were reviewed. Subjects consisted of 23 males (64%) and 13 females (36%), and the age at operation ranged from 12 months to 6 years (mean age = 3 years and 6 months). The number of congenital cholesteatoma was as follows: 26 patients at stage I and 10 patients at stage II. The follow-up duration was between 12 and 56 months, with an average of 30 months. There were no postoperative complications such as tympanic membrane perforation, dizziness, or secondary middle ear infection. Among 36 patients who had undergone the MITM approach for the treatment of congenital cholesteatoma, five (13.8%) showed recurrence and underwent a second-look operation. On the basis of our data, the MITM approach is a useful surgical technique for early stage congenital cholesteatoma in children. It has many advantages, in that there is no external wound and it is a simple surgical technique that involves easy postoperative care, a short operation time and hospitalization period, avoidance of serious complications, and easy repeatability for recurrence. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

  9. Comparison and analysis of membrane fouling between flocculent sludge membrane bioreactor and granular sludge membrane bioreactor.

    Directory of Open Access Journals (Sweden)

    Wang Jing-Feng

    Full Text Available The goal of this study is to investigate the effect of inoculating granules on reducing membrane fouling. In order to evaluate the differences in performance between flocculent sludge and aerobic granular sludge in membrane reactors (MBRs, two reactors were run in parallel and various parameters related to membrane fouling were measured. The results indicated that specific resistance to the fouling layer was five times greater than that of mixed liquor sludge in the granular MBR. The floc sludge more easily formed a compact layer on the membrane surface, and increased membrane resistance. Specifically, the floc sludge had a higher moisture content, extracellular polymeric substances concentration, and negative surface charge. In contrast, aerobic granules could improve structural integrity and strength, which contributed to the preferable permeate performance. Therefore, inoculating aerobic granules in a MBR presents an effective method of reducing the membrane fouling associated with floc sludge the perspective of from the morphological characteristics of microbial aggregates.

  10. Degradation of Polypropylene Membranes Applied in Membrane Distillation Crystallizer

    Directory of Open Access Journals (Sweden)

    Marek Gryta

    2016-03-01

    Full Text Available The studies on the resistance to degradation of capillary polypropylene membranes assembled in a membrane crystallizer were performed. The supersaturation state of salt was achieved by evaporation of water from the NaCl saturated solutions using membrane distillation process. A high feed temperature (363 K was used in order to enhance the degradation effects and to shorten the test times. Salt crystallization was carried out by the application of batch or fluidized bed crystallizer. A significant membrane scaling was observed regardless of the method of realized crystallization. The SEM-EDS, DSC, and FTIR methods were used for investigations of polypropylene degradation. The salt crystallization onto the membrane surface accelerated polypropylene degradation. Due to a polymer degradation, the presence of carbonyl groups on the membranes’ surface was identified. Besides the changes in the chemical structure a significant mechanical damage of the membranes, mainly caused by the internal scaling, was also found. As a result, the membranes were severely damaged after 150 h of process operation. A high level of salt rejection was maintained despite damage to the external membrane surface.

  11. Capping of the radicular exposed surface (part II). Surgical and not surgical treatment

    OpenAIRE

    Grados Pomarino, Sixto; Estrada, Andrew Alejandro; Maetahara Rubio, Denis Miguel; Guzmán Vera, Yanina Sara; Tello Barbarán, Javier

    2014-01-01

    The gingival recession treatment can be made surgical1y with a high predictability of success due to the great advance during the last ones of the mucogingival surgical techniques. The use of connective grafts in coverage of recessions has obtained high rates of success reason why these procedures are common within the modern periodontal surgical practice. Knowing that all patients do not accept the surgical treatment, many investigators have come studying the possibility of treating non-surg...

  12. Pretreatment and Membrane Hydrophilic Modification to Reduce Membrane Fouling

    Directory of Open Access Journals (Sweden)

    Huaqiang Chu

    2013-09-01

    Full Text Available The application of low pressure membranes (microfiltration/ultrafiltration has undergone accelerated development for drinking water production. However, the major obstacle encountered in its popularization is membrane fouling caused by natural organic matter (NOM. This paper firstly summarizes the two factors causing the organic membrane fouling, including molecular weight (MW and hydrophilicity/hydrophobicity of NOM, and then presents a brief introduction of the methods which can prevent membrane fouling such as pretreatment of the feed water (e.g., coagulation, adsorption, and pre-oxidation and membrane hydrophilic modification (e.g., plasma modification, irradiation grafting modification, surface coating modification, blend modification, etc.. Perspectives of further research are also discussed.

  13. Radiation-induced damage of membranes

    International Nuclear Information System (INIS)

    Yonei, Shuji

    1977-01-01

    An outline of membranous structure was stated, and radiation-induced damage of membranes were surveyed. By irradiation, permeability of membranes, especially passive transportation mechanism, was damaged, and glycoprotein in the surface layers of cells and the surface layer structures were changed. The intramembranous damage was induced by decrease of electrophoresis of nuclear mambranes and a quantitative change of cytochrome P450 of microsomal membranes of the liver, and peroxidation of membranous lipid and SH substitute damage of membranous protein were mentioned as the mechanism of membranous damage. Recovery of membranous damage depends on radiation dose and temperature, and membranous damage participates largely in proliferation death. (tsunoda, M.)

  14. Radio-chemical applications of functionalized membranes

    International Nuclear Information System (INIS)

    Pandey, Ashok K.

    2011-01-01

    Functionalized polymer membranes have many potential applications as they are task specific. We have developed many functionalized membranes like polymer inclusion membranes, pore-filled membranes and nano-membranes. Radiotracers and other methods have been used to understand the diffusional-transport properties of the Nafion-117 membrane as well as home-made membranes. These membranes have been used to develop novel analytical and separation methods for toxic metal ions and radionuclides. In this talk, an overview of our work on functionalized membrane is presented. (author)

  15. Operation of staged membrane oxidation reactor systems

    Science.gov (United States)

    Repasky, John Michael

    2012-10-16

    A method of operating a multi-stage ion transport membrane oxidation system. The method comprises providing a multi-stage ion transport membrane oxidation system with at least a first membrane oxidation stage and a second membrane oxidation stage, operating the ion transport membrane oxidation system at operating conditions including a characteristic temperature of the first membrane oxidation stage and a characteristic temperature of the second membrane oxidation stage; and controlling the production capacity and/or the product quality by changing the characteristic temperature of the first membrane oxidation stage and/or changing the characteristic temperature of the second membrane oxidation stage.

  16. The Virtual Surgical Pelvis : Anatomy Visualization for Education and Surgical Planning

    NARCIS (Netherlands)

    Smit, N.N.

    2016-01-01

    This thesis deals with visualizing anatomical data for medical education and surgical planning purposes. To this end, we have developed a detailed virtual atlas, the Virtual Surgical Pelvis (VSP),which unifies surgically relevant knowledge on pelvic anatomy. We provide methods to share the knowledge

  17. Emergent geometry of membranes

    Energy Technology Data Exchange (ETDEWEB)

    Badyn, Mathias Hudoba de; Karczmarek, Joanna L.; Sabella-Garnier, Philippe; Yeh, Ken Huai-Che [Department of Physics and Astronomy, University of British Columbia,6224 Agricultural Road, Vancouver (Canada)

    2015-11-13

    In work http://dx.doi.org/10.1103/PhysRevD.86.086001, a surface embedded in flat ℝ{sup 3} is associated to any three hermitian matrices. We study this emergent surface when the matrices are large, by constructing coherent states corresponding to points in the emergent geometry. We find the original matrices determine not only shape of the emergent surface, but also a unique Poisson structure. We prove that commutators of matrix operators correspond to Poisson brackets. Through our construction, we can realize arbitrary noncommutative membranes: for example, we examine a round sphere with a non-spherically symmetric Poisson structure. We also give a natural construction for a noncommutative torus embedded in ℝ{sup 3}. Finally, we make remarks about area and find matrix equations for minimal area surfaces.

  18. Real-time inextensible surgical thread simulation.

    Science.gov (United States)

    Xu, Lang; Liu, Qian

    2018-03-27

    This paper discusses a real-time simulation method of inextensible surgical thread based on the Cosserat rod theory using position-based dynamics (PBD). The method realizes stable twining and knotting of surgical thread while including inextensibility, bending, twisting and coupling effects. The Cosserat rod theory is used to model the nonlinear elastic behavior of surgical thread. The surgical thread model is solved with PBD to achieve a real-time, extremely stable simulation. Due to the one-dimensional linear structure of surgical thread, the direct solution of the distance constraint based on tridiagonal matrix algorithm is used to enhance stretching resistance in every constraint projection iteration. In addition, continuous collision detection and collision response guarantee a large time step and high performance. Furthermore, friction is integrated into the constraint projection process to stabilize the twining of multiple threads and complex contact situations. Through comparisons with existing methods, the surgical thread maintains constant length under large deformation after applying the direct distance constraint in our method. The twining and knotting of multiple threads correspond to stable solutions to contact and friction forces. A surgical suture scene is also modeled to demonstrate the practicality and simplicity of our method. Our method achieves stable and fast simulation of inextensible surgical thread. Benefiting from the unified particle framework, the rigid body, elastic rod, and soft body can be simultaneously simulated. The method is appropriate for applications in virtual surgery that require multiple dynamic bodies.

  19. Optimisation of surgical care for rectal cancer

    NARCIS (Netherlands)

    Borstlap, W.A.A.

    2017-01-01

    Optimisation of surgical care means weighing the risk of treatment related morbidity against the patients’ potential benefits of a surgical intervention. The first part of this thesis focusses on the anaemic patient undergoing colorectal surgery. Hypothesizing that a more profound haemoglobin

  20. Communication Skills among Surgical Trainees: Perceptions of ...

    African Journals Online (AJOL)

    Objective Communication between the surgeon and the patient is a core clinical skill. The ability to communicate with patients and their family members is very important in the optimum care of the surgical patient. Few studies have assessed communication between surgical trainees and their patients in sub-Saharan Africa.

  1. Surgical evaluation of acute abdomen in pregnancy

    International Nuclear Information System (INIS)

    Kovarova, P.

    2013-01-01

    Acute abdomen in pregnancy is a disease with a low incidence. The purpose of this work was therefore to create a review of current recommended practice in diagnostics and surgical solution. I also mention surgically relevant physiological and pathological changes specific to pregnancy, differential diagnostics of acute abdomen in pregnancy and impact of the disease and its treatment on the fetus. (author)

  2. Evolution of hemostatic agents in surgical practice

    Directory of Open Access Journals (Sweden)

    Chandru P Sundaram

    2010-01-01

    Conclusions : A review of the evolution of topical hemostatic agents highlights opportunities for potential novel research. Fibrin sealants may have the most opportunity for advancement, and understanding the history of these products is useful. With the drive in urology for minimally invasive surgical techniques, adaptation of topical hemostatic agents to this surgical approach would be valuable and offers an opportunity for novel contributions.

  3. Surgical treatment of gynecomastia: complications and outcomes.

    Science.gov (United States)

    Li, Chun-Chang; Fu, Ju-Peng; Chang, Shun-Cheng; Chen, Tim-Mo; Chen, Shyi-Gen

    2012-11-01

    Gynecomastia is defined as the benign enlargement of the male breast. Multiple surgical options have been used to improve outcomes. The aim of this study was to analyze the surgical approaches to the treatment of gynecomastia and their outcomes over a 10-year period. All patients undergoing surgical correction of gynecomastia in our department between 2000 and 2010 were included for retrospective evaluation. The data were analyzed for etiology, stage of gynecomastia, surgical technique, complications, risk factors, and revision rate. The surgical result was evaluated with self-assessment questionnaires. A total of 41 patients with 75 operations were included. Techniques included subcutaneous mastectomy alone or with additional ultrasound-assisted liposuction (UAL) and isolated UAL. The surgical revision rate for all patients was 4.8%. The skin-sparing procedure gave good surgical results in grade IIb and grade III gynecomastia with low revision and complication rates. The self-assessment report revealed a good level of overall satisfaction and improvement in self-confidence (average scores 9.4 and 9.2, respectively, on a 10-point scale). The treatment of gynecomastia requires an individualized approach. Subcutaneous mastectomy combined with UAL could be used as the first choice for surgical treatment of grade II and III gynecomastia.

  4. Surgical Site Infection among Patients Undergone Orthopaedic ...

    African Journals Online (AJOL)

    ADMIN

    with surgical site infection at Muhimbili Orthopedic Institute. ... Determination of the relationship between outcome and exposure variables ... determined by more than 2 hours length of surgical procedure (AOR= 1.4; 95%CI 1.14-6.69; ... hospital, those with metastatic fractures, back, spine were not included as they fall under.

  5. SURGICAL ORTHODONTICS: LITERATURE REVIEW AND CASE REPORT

    OpenAIRE

    Piyush HEDA; Babita RAGHUWANSHI; Amit PRAKASH; Kishore SONAWANE

    2013-01-01

    Orthognathic surgery is a surgical procedure largely practiced throughout the world for the correction of various maxillofacial deformities. The procedure for correcting a particular deformity will be done after proper evaluation, which includes cephalometric, dental model analysis and photographs. The patient undergoes pre-surgical orthodontic correction for dental compensation, after which surgery is planned. During the last few decades, the profession has witnessed ...

  6. Systems for tracking minimally invasive surgical instruments

    NARCIS (Netherlands)

    Chmarra, M. K.; Grimbergen, C. A.; Dankelman, J.

    2007-01-01

    Minimally invasive surgery (e.g. laparoscopy) requires special surgical skills, which should be objectively assessed. Several studies have shown that motion analysis is a valuable assessment tool of basic surgical skills in laparoscopy. However, to use motion analysis as the assessment tool, it is

  7. Surgical site infection among patients undergone orthopaedic ...

    African Journals Online (AJOL)

    Surgical site infection among patients undergone orthopaedic surgery at Muhimbili Orthopaedic Institute, Dar es Salaam, Tanzania. ... of surgical site infection at Muhimbili Orthopedic Institute was high. This was associated with more than 2 hours length of surgery, lack of prophylaxis use, and pre-operative hospital stay.

  8. Radiodiagnosis of lung syndrome in surgical sepsis

    International Nuclear Information System (INIS)

    Dvojnykh, V.P.; Palagin, E.K.

    1991-01-01

    The results of treatment of 23 patients with acute surgical sepsis were analysed. It was shown that the X-ray examination must be obligatory in surveillance of patients with purulent foci. Two roentgenological variants are possible in surgical sepsis: central and perepheric. X-ray examinations of chest organs should be conducted every 2-3 day

  9. Photoreceptor change and visual outcome after idiopathic epiretinal membrane removal with or without additional internal limiting membrane peeling.

    Science.gov (United States)

    Ahn, Seong Joon; Ahn, Jeeyun; Woo, Se Joon; Park, Kyu Hyung

    2014-01-01

    To compare the postoperative photoreceptor status and visual outcome after epiretinal membrane removal with or without additional internal limiting membrane (ILM) peeling. Medical records of 40 eyes from 37 patients undergoing epiretinal membrane removal with residual ILM peeling (additional ILM peeling group) and 69 eyes from 65 patients undergoing epiretinal membrane removal without additional ILM peeling (no additional peeling group) were reviewed. The length of defects in cone outer segment tips, inner segment/outer segment junction, and external limiting membrane line were measured using spectral domain optical coherence tomography images of the fovea before and at 1, 3, 6, and 12 months after the surgery. Cone outer segment tips and inner segment/outer segment junction line defects were most severe at postoperative 1 month and gradually restored at 12 months postoperatively. The cone outer segment tips line defect in the additional ILM peeling group was significantly greater than that in the no additional peeling group at postoperative 1 month (P = 0.006), and best-corrected visual acuity was significantly worse in the former group at the same month (P = 0.001). There was no significant difference in the defect size and best-corrected visual acuity at subsequent visits and recurrence rates between the two groups. Patients who received epiretinal membrane surgery without additional ILM peeling showed better visual and anatomical outcome than those with additional ILM peeling at postoperative 1 month. However, surgical outcomes were comparable between the two groups, thereafter. In terms of visual outcome and photoreceptor integrity, additional ILM peeling may not be an essential procedure.

  10. Modelling of proteins in membranes

    DEFF Research Database (Denmark)

    Sperotto, Maria Maddalena; May, S.; Baumgaertner, A.

    2006-01-01

    This review describes some recent theories and simulations of mesoscopic and microscopic models of lipid membranes with embedded or attached proteins. We summarize results supporting our understanding of phenomena for which the activities of proteins in membranes are expected to be significantly ...

  11. Fabrication of green polymeric membranes

    KAUST Repository

    Kim, Dooli; Nunes, Suzana Pereira

    2017-01-01

    Provided herein are methods of fabricating membranes using polymers with functionalized groups such as sulfone (e.g., PSf and PES), ether (e.g., PES), acrylonitrile (e.g., PAN), fluoride(e.g., pvdf and other fluoropolymers), and imide (e.g., extem) and ionic liquids. Also provided are membranes made by the provided methods.

  12. Gas separation membranes current status

    International Nuclear Information System (INIS)

    Puri, S.P.

    1996-01-01

    Membrane-based gas separation systems are now widely accepted and employed as unit operation in industrial gas, chemical and allied industries. Following their successful commercialization in the late Seventies to recover hydrogen from ammonia purge gas streams, membrane-based systems have gained acceptance in a wide variety of applications

  13. Membranes for Enhanced Emulsification Processes

    NARCIS (Netherlands)

    Güell, Carme; Ferrando, Montse; Schroen, C.G.P.H.

    2016-01-01

    The use of membrane technology for the production of single and double emulsions has been proven feasible for a wide range of systems. The low energy requirements and mild process conditions (shear stress and temperature) of membrane emulsification (ME) compared to conventional processes makes it of

  14. Fabrication of green polymeric membranes

    KAUST Repository

    Kim, Dooli

    2017-06-16

    Provided herein are methods of fabricating membranes using polymers with functionalized groups such as sulfone (e.g., PSf and PES), ether (e.g., PES), acrylonitrile (e.g., PAN), fluoride(e.g., pvdf and other fluoropolymers), and imide (e.g., extem) and ionic liquids. Also provided are membranes made by the provided methods.

  15. Biogenesis of plasma membrane cholesterol

    International Nuclear Information System (INIS)

    Lange, Y.

    1986-01-01

    A striking feature of the molecular organization of eukaryotic cells is the singular enrichment of their plasma membranes in sterols. The authors studies are directed at elucidating the mechanisms underlying this inhomogeneous disposition. Cholesterol oxidase catalyzes the oxidation of plasma membrane cholesterol in intact cells, leaving intracellular cholesterol pools untouched. With this technique, the plasma membrane was shown to contain 95% of the unesterified cholesterol of cultured human fibroblasts. Cholesterol synthesized from [ 3 H] acetate moved to the plasma membrane with a half-time of 1 h at 37 0 C. They used equilibrium gradient centrifugation of homogenates of biosynthetically labeled, cholesterol oxidase treated cells to examine the distribution of newly synthesized sterols among intracellular pools. Surprisingly, lanosterol, a major precursor of cholesterol, and intracellular cholesterol both peaked at much lower buoyant density than did 3-hydroxy-3-methylglutaryl-CoA reductase. This suggests that cholesterol biosynthesis is not taken to completion in the endoplasmic reticulum. The cholesterol in the buoyant fraction eventually moved to the plasma membrane. Digitonin treatment increased the density of the newly synthesized cholesterol fractions, indicating that nascent cholesterol in transit is associated with cholesterol-rich membranes. The authors are testing the hypothesis that the pathway of cholesterol biosynthesis is spatially organized in various intracellular membranes such that the sequence of biosynthetic steps both concentrates the sterol and conveys it to the plasma membrane

  16. Surgical treatment for residual or recurrent strabismus

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2014-12-01

    Full Text Available Although the surgical treatment is a relatively effective and predictable method for correcting residual or recurrent strabismus, such as posterior fixation sutures, medial rectus marginal myotomy, unilateral or bilateral rectus re-recession and resection, unilateral lateral rectus recession and adjustable suture, no standard protocol is established for the surgical style. Different surgical approaches have been recommended for correcting residual or recurrent strabismus. The choice of the surgical procedure depends on the former operation pattern and the surgical dosages applied on the patients, residual or recurrent angle of deviation and the operator''s preference and experience. This review attempts to outline recent publications and current opinion in the management of residual or recurrent esotropia and exotropia.

  17. The effect of fasting on surgical performance

    DEFF Research Database (Denmark)

    Schefte, David Fenger; Rosenstock, Steffen Jais

    2016-01-01

    BACKGROUND: It is unknown whether fasting has any impact on surgical performance. This simulator-based study investigates whether fasting affects surgical performance. METHODS: Twelve healthy medical students [seven women, mean age 26.5 years (range 23-34)] with no prior experience with surgical...... simulators underwent a short course introduction to the LapSim(®) simulator. After having reached a predefined level, the participants performed five simulated salpingectomies on the LapSim(®) simulator 5-30 days after the initial introduction. The procedures took place at 9 a.m. and 2 p.m. after fasting...... in the longitudinal axis with the left hand. CONCLUSION: The simulator-based study suggests that 17 h of fasting does not deteriorate surgical performance. Further studies on the effect of fasting on surgical performance are needed....

  18. Multimodal strategies to improve surgical outcome

    DEFF Research Database (Denmark)

    Kehlet, Henrik; Wilmore, Douglas W

    2002-01-01

    OBJECTIVE: To evaluate the effect of modifying perioperative care in noncardiac surgical patients on morbidity, mortality, and other outcome measures. BACKGROUND: New approaches in pain control, introduction of techniques that reduce the perioperative stress response, and the more frequent use...... anesthesia in elective operations, and pilot studies of fast track surgical procedures using the multimodality approach. RESULTS: The introduction of newer approaches to perioperative care has reduced both morbidity and mortality in surgical patients. In the future, most elective operations will become day...... surgical procedures or require only 1 to 2 days of postoperative hospitalization. Reorganization of the perioperative team (anesthesiologists, surgeons, nurses, and physical therapists) will be essential to achieve successful fast track surgical programs. CONCLUSIONS: Understanding perioperative...

  19. Staged membrane oxidation reactor system

    Science.gov (United States)

    Repasky, John Michael; Carolan, Michael Francis; Stein, VanEric Edward; Chen, Christopher Ming-Poh

    2012-09-11

    Ion transport membrane oxidation system comprising (a) two or more membrane oxidation stages, each stage comprising a reactant zone, an oxidant zone, one or more ion transport membranes separating the reactant zone from the oxidant zone, a reactant gas inlet region, a reactant gas outlet region, an oxidant gas inlet region, and an oxidant gas outlet region; (b) an interstage reactant gas flow path disposed between each pair of membrane oxidation stages and adapted to place the reactant gas outlet region of a first stage of the pair in flow communication with the reactant gas inlet region of a second stage of the pair; and (c) one or more reactant interstage feed gas lines, each line being in flow communication with any interstage reactant gas flow path or with the reactant zone of any membrane oxidation stage receiving interstage reactant gas.

  20. Ceramic membrane development in NGK

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Kiyoshi; Sakai, Hitoshi, E-mail: kinsakai@ngk.co.jp [Corporate R and D, NGK Insulators, Ltd., Nagoya 467-8530 (Japan)

    2011-05-15

    NGK Insulators, Ltd. was established in 1919 to manufacture the electric porcelain insulators for power transmission lines. Since then, our business has grown as one of the world-leading ceramics manufacturing companies and currently supply with the various environmentally-benign ceramic products to worldwide. In this paper, ceramic membrane development in NGK is described in detail. We have been selling ceramic microfiltration (MF) membranes and ultra-filtration (UF) membranes for many years to be used for solid/liquid separation in various fields such as pharmaceutical, chemical, food and semiconductor industries. In Corporate R and D, new ceramic membranes with sub-nanometer sized pores, which are fabricated on top of the membrane filters as support, are under development for gas and liquid/liquid separation processes.

  1. Ceramic membrane development in NGK

    Science.gov (United States)

    Araki, Kiyoshi; Sakai, Hitoshi

    2011-05-01

    NGK Insulators, Ltd. was established in 1919 to manufacture the electric porcelain insulators for power transmission lines. Since then, our business has grown as one of the world-leading ceramics manufacturing companies and currently supply with the various environmentally-benign ceramic products to worldwide. In this paper, ceramic membrane development in NGK is described in detail. We have been selling ceramic microfiltration (MF) membranes and ultra-filtration (UF) membranes for many years to be used for solid/liquid separation in various fields such as pharmaceutical, chemical, food and semiconductor industries. In Corporate R&D, new ceramic membranes with sub-nanometer sized pores, which are fabricated on top of the membrane filters as support, are under development for gas and liquid/liquid separation processes.

  2. Hydrogen Selective Exfoliated Zeolite Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Tsapatsis, Michael [Univ. of Minnesota, Minneapolis, MN (United States). Department of Chemical Engineering and Materials Science; Daoutidis, Prodromos [Univ. of Minnesota, Minneapolis, MN (United States). Department of Chemical Engineering and Materials Science; Elyassi, Bahman [Univ. of Minnesota, Minneapolis, MN (United States). Department of Chemical Engineering and Materials Science; Lima, Fernando [Univ. of Minnesota, Minneapolis, MN (United States). Department of Chemical Engineering and Materials Science; Iyer, Aparna [Univ. of Minnesota, Minneapolis, MN (United States). Department of Chemical Engineering and Materials Science; Agrawal, Kumar [Univ. of Minnesota, Minneapolis, MN (United States). Department of Chemical Engineering and Materials Science; Sabnis, Sanket [Univ. of Minnesota, Minneapolis, MN (United States). Department of Chemical Engineering and Materials Science

    2015-04-06

    The objective of this project was to develop and evaluate an innovative membrane technology at process conditions that would be representative of Integrated Gasification Combined Cycle (IGCC) advanced power generation with pre-combustion capture of carbon dioxide (CO2). This research focused on hydrogen (H2)-selective zeolite membranes that could be utilized to separate conditioned syngas into H2-rich and CO2-rich components. Both experiments and process design and optimization calculations were performed to evaluate the concept of ultra-thin membranes made from zeolites nanosheets. In this work, efforts in the laboratory were made to tackle two fundamental challenges in application of zeolite membranes in harsh industrial environments, namely, membrane thickness and membrane stability. Conventional zeolite membranes have thicknesses in the micron range, limiting their performance. In this research, we developed a method for fabrication of ultimately thin zeolite membranes based on zeolite nanosheets. A range of layered zeolites (MWW, RWR, NSI structure types) suitable for hydrogen separation was successfully exfoliated to their constituent nanosheets. Further, membranes were made from one of these zeolites, MWW, to demonstrate the potential of this group of materials. Moreover, long-term steam stability of these zeolites (up to 6 months) was investigated in high concentrations of steam (35 mol% and 95 mole%), high pressure (10 barg), and high temperatures (350 °C and 600 °C) relevant to conditions of water-gas-shift and steam methane reforming reactions. It was found that certain nanosheets are stable, and that stability depends on the concentration of structural defects. Additionally, models that represent a water-gas-shift (WGS) membrane reactor equipped with the zeolite membrane were developed for systems studies. These studies had the aim of analyzing the effect of the membrane reactor integration into IGCC plants

  3. POLYMER ELECTROLYTE MEMBRANE FUEL CELLS

    DEFF Research Database (Denmark)

    2001-01-01

    A method for preparing polybenzimidazole or polybenzimidazole blend membranes and fabricating gas diffusion electrodes and membrane-electrode assemblies is provided for a high temperature polymer electrolyte membrane fuel cell. Blend polymer electrolyte membranes based on PBI and various...... thermoplastic polymers for high temperature polymer electrolyte fuel cells have also been developed. Miscible blends are used for solution casting of polymer membranes (solid electrolytes). High conductivity and enhanced mechanical strength were obtained for the blend polymer solid electrolytes....... With the thermally resistant polymer, e.g., polybenzimidazole or a mixture of polybenzimidazole and other thermoplastics as binder, the carbon-supported noble metal catalyst is tape-cast onto a hydrophobic supporting substrate. When doped with an acid mixture, electrodes are assembled with an acid doped solid...

  4. Nanoporous Membrane Technologies for Pathogen Collection, Separation, and Detection

    National Research Council Canada - National Science Library

    Lee, Sang W; Shang, Hao; Lee, Gil U; Griffin, Matthew T; Fulton, Jack

    2003-01-01

    Partial contents: Nanoporous Membranes, Membrane Chemistries, Characterization of Membrane Chemistries,Protein Fouling, Collector,Gas and Liquid Permeabilities, Membrane Permeabilities in the Presence of Water...

  5. Comparison of the performance of natural latex membranes prepared with different procedures and PTFE membrane in guided bone regeneration (GBR) in rabbits.

    Science.gov (United States)

    Moura, Jonas M L; Ferreira, Juliana F; Marques, Leonardo; Holgado, Leandro; Graeff, Carlos F O; Kinoshita, Angela

    2014-09-01

    This work assessed the performance of membranes made of natural latex extracted from Hevea brasiliensis prepared with three different methods: polymerized immediately after collection without the use of ammonia (L1); polymerized after preservation in ammonia solution (L2); and polymerized after storage in ammonia, followed by Soxhlet technique for the extraction of substances (L3). Polytetrafluoroethylene (PTFE) membrane was used as control. Two 10-mm diameter bone defects were surgically made in the calvaria of thirty adult male New Zealand rabbits. Defects (total n = 60) were treated with guided bone regeneration (GBR) using L1, L2, L3 or PTFE membranes (n = 15 for each membrane). Ten animals were euthanized after 7, 20 and 60 days postoperatively so that five samples (n = 5) of each treatment were collected at each time, and bone regeneration was assessed microscopically. The microscopic analysis revealed defects filled with blood clot and new bone formation at the margins of the defect in all 7-day samples, while 20-day defects were mainly filled with fibrous connective tissue. After 60 days defects covered with L1 membranes showed a significantly larger bone formation area in comparison to the other groups (P PTFE membranes was also investigated in six additional rabbits. The animals were subjected to the same surgical procedure for the confection of one 10-mm diameter bone defect that was treated with L1 (n = 3) or PTFE (n = 3). Fifty-three days later, a second surgery was performed to make a second defect, which was treated with the same type of membrane used in the first surgery. Seven days later, the animals were euthanized and samples analyzed. No differences among L1 and PTFE samples collected from sensitized and non-sensitized animals were found (P > 0.05, Kruskal-Wallis). Therefore, the results demonstrated that latex membranes presented performance comparable to PTFE membranes, and that L1 membranes induced higher bone formation. L1 and

  6. Drug-model membrane interactions

    International Nuclear Information System (INIS)

    Deniz, Usha K.

    1994-01-01

    In the present day world, drugs play a very important role in medicine and it is necessary to understand their mode of action at the molecular level, in order to optimise their use. Studies of drug-biomembrane interactions are essential for gaining such as understanding. However, it would be prohibitively difficult to carry out such studies, since biomembranes are highly complex systems. Hence, model membranes (made up of these lipids which are important components of biomembranes) of varying degrees of complexity are used to investigate drug-membrane interactions. Bio- as well as model-membranes undergo a chain melting transition when heated, the chains being in a disordered state above the transition point, T CM . This transition is of physiological importance since biomembranes select their components such that T CM is less than the ambient temperature but not very much so, so that membrane flexibility is ensured and porosity, avoided. The influence of drugs on the transition gives valuable clues about various parameters such as the location of the drug in the membrane. Deep insights into drug-membrane interactions are obtained by observing the effect of drugs on membrane structure and the mobilities of the various groups in lipids, near T CM . Investigation of such changes have been carried out with several drugs, using techniques such as DSC, XRD and NMR. The results indicate that the drug-membrane interaction not only depends on the nature of drug and lipids but also on the form of the model membrane - stacked bilayer or vesicles. The light that these results shed on the nature of drug-membrane interactions is discussed. (author). 13 refs., 13 figs., 1 tab

  7. Buried penis: classification surgical approach.

    Science.gov (United States)

    Hadidi, Ahmed T

    2014-02-01

    The purpose of this study was to describe morphological classification of congenital buried penis (BP) and present a versatile surgical approach for correction. Sixty-one patients referred with BP were classified into 3 grades according to morphological findings: Grade 1-29 patients with Longer Inner Prepuce (LIP) only, Grade II-20 patients who presented with LIP associated with indrawn penis that required division of the fundiform and suspensory ligaments, and Grade III-12 patients who had in addition to the above, excess supra-pubic fat. A ventral midline penile incision extending from the tip of prepuce down to the penoscrotal junction was used in all patients. The operation was tailored according to the BP Grade. All patients underwent circumcision. Mean follow up was 3 years (range 1 to 10). All 61 patients had an abnormally long inner prepuce (LIP). Forty-seven patients had a short penile shaft. Early improvement was noted in all cases. Satisfactory results were achieved in all 29 patients in grade I and in 27 patients in grades II and III. Five children (Grades II and III) required further surgery (9%). Congenital buried penis is a spectrum characterized by LIP and may include in addition; short penile shaft, abnormal attachment of fundiform, and suspensory ligaments and excess supra-pubic fat. Congenital Mega Prepuce (CMP) is a variant of Grade I BP, with LIP characterized by intermittent ballooning of the genital area. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Surgical treatment of radiation enteritis

    Energy Technology Data Exchange (ETDEWEB)

    Cross, M.J.; Frazee, R.C. (Department of General Surgery, Scott and White Memorial Hospital, Temple TX (United States))

    1992-02-01

    Radiation enteritis is a progressive, disease process that causes intestinal fibrosis and obliterative endarteritis, which results in significant morbidity and mortality. The authors' clinical experience involving 20 patients over a 22-year period from 1967 through 1989 who underwent various surgical procedures to alleviate chronic symptoms secondary to radiation enteritis is described. Eight men and 12 women with a mean age of 52 years (24 to 81 years) underwent a total of 27 procedures for complications of radiation enteritis. Radiation therapy was delivered for treatment of gynecologic malignancies (55%), colorectal cancer (20%), prostate malignancies (10%), and others (15%). The mean average dose of radiation delivered was 5,514 rads with a range of 2,613 to 7,000 rads. The interval from radiation treatment to time of surgery averaged 9 years. Operative procedures consisted of 12 resection and primary anastomosis procedures and 15 resections with stoma creation. Formation of a stoma was used in patients with more severe disease. The 30-day operative mortality was 0% and morbidity was 55%. There were no anastomotic leaks or intra-abdominal abscesses. The authors conclude that resection and primary anastomosis can safely be performed in selected patients but that judicious use of stoma formation can avoid major mortality and morbidity associated with surgery in this setting.

  9. Surgical treatment of radiation enteritis

    International Nuclear Information System (INIS)

    Cross, M.J.; Frazee, R.C.

    1992-01-01

    Radiation enteritis is a progressive, disease process that causes intestinal fibrosis and obliterative endarteritis, which results in significant morbidity and mortality. The authors' clinical experience involving 20 patients over a 22-year period from 1967 through 1989 who underwent various surgical procedures to alleviate chronic symptoms secondary to radiation enteritis is described. Eight men and 12 women with a mean age of 52 years (24 to 81 years) underwent a total of 27 procedures for complications of radiation enteritis. Radiation therapy was delivered for treatment of gynecologic malignancies (55%), colorectal cancer (20%), prostate malignancies (10%), and others (15%). The mean average dose of radiation delivered was 5,514 rads with a range of 2,613 to 7,000 rads. The interval from radiation treatment to time of surgery averaged 9 years. Operative procedures consisted of 12 resection and primary anastomosis procedures and 15 resections with stoma creation. Formation of a stoma was used in patients with more severe disease. The 30-day operative mortality was 0% and morbidity was 55%. There were no anastomotic leaks or intra-abdominal abscesses. The authors conclude that resection and primary anastomosis can safely be performed in selected patients but that judicious use of stoma formation can avoid major mortality and morbidity associated with surgery in this setting

  10. Surgical Treatment for Pulmonary Hamartomas

    Directory of Open Access Journals (Sweden)

    Funda Ižncekara

    2015-11-01

    Full Text Available Aim: In this study, we evaluated the patients operated for hamartoma and treated endobronchially and the diagnostic value of this approach has been examined. Material and Method: 59 patients (24 females, 35 males; mean age 53 years, range 28-78 years which were operated and endobronchial treated for hamartoma in our clinic between January 2003 - January 2013 were analyzed retrospectively. Patient age, sex, symptoms, histopathological, surgical procedures and treatment outcomes were evaluated. Results: The most common complaint was shortness of breath, while 25 patients were asymptomatic. Thoracotomy and mass enucleation in 29 patients (%49,15, thoracotomy and wedge resection in 18 patients (%30.5, VATS and wedge resection in 4 patients (%6.77, thoracotomy and upper lobectomy in 4 patients (%6.77, thoracotomy and lower lobectomy in 2 patients (%3.38 and left upper lobe segmentectomy in 1 patient (%1.69 and right upper bronchial sleeve resection in 1 patient were performed. The postoperative pathology of lesions examined and diagnosis were chondroid hamartoma in 28 , pulmonary hamartoma in 20 , hamartoma chondrolypomatous in 11 and the bronchial hamartoma in 2 . No mortality was observed intraoperatively. Discussion: Although hamartomas are benign , diagnosis should be made because it can be confused with lung cancer. Definitive diagnosis and treatment can be performed successfully through VATS in primarily appropriate cases with minimal morbidity or thoracotomy or endobronchial treatment.

  11. [Surgical treatment of anal fistula].

    Science.gov (United States)

    Zeng, Xiandong; Zhang, Yong

    2014-12-01

    Anal fistula is a common disease. It is also quite difficult to be solved without recurrence or damage to the anal sphincter. Several techniques have been described for the management of anal fistula, but there is no final conclusion of their application in the treatment. This article summarizes the history of anal fistula management, the current techniques available, and describes new technologies. Internet online searches were performed from the CNKI and Wanfang databases to identify articles about anal fistula management including seton, fistulotomy, fistulectomy, LIFT operation, biomaterial treatment and new technology application. Every fistula surgery technique has its own place, so it is reasonable to give comprehensive individualized treatment to different patients, which may lead to reduced recurrence and avoidance of damage to the anal sphincter. New technologies provide promising alternatives to traditional methods of management. Surgeons still need to focus on the invention and improvement of the minimally invasive techniques. Besides, a new therapeutic idea is worth to explore that the focus of surgical treatment should be transferred to prevention of the formation of anal fistula after perianal abscess.

  12. Audit of Orthopaedic Surgical Documentation

    Directory of Open Access Journals (Sweden)

    Fionn Coughlan

    2015-01-01

    Full Text Available Introduction. The Royal College of Surgeons in England published guidelines in 2008 outlining the information that should be documented at each surgery. St. James’s Hospital uses a standard operation sheet for all surgical procedures and these were examined to assess documentation standards. Objectives. To retrospectively audit the hand written orthopaedic operative notes according to established guidelines. Methods. A total of 63 operation notes over seven months were audited in terms of date and time of surgery, surgeon, procedure, elective or emergency indication, operative diagnosis, incision details, signature, closure details, tourniquet time, postop instructions, complications, prosthesis, and serial numbers. Results. A consultant performed 71.4% of procedures; however, 85.7% of the operative notes were written by the registrar. The date and time of surgery, name of surgeon, procedure name, and signature were documented in all cases. The operative diagnosis and postoperative instructions were frequently not documented in the designated location. Incision details were included in 81.7% and prosthesis details in only 30% while the tourniquet time was not documented in any. Conclusion. Completion and documentation of operative procedures were excellent in some areas; improvement is needed in documenting tourniquet time, prosthesis and incision details, and the location of operative diagnosis and postoperative instructions.

  13. Effects of a chitosan membrane coated with polylactic and polyglycolic acid on bone regeneration in a rat calvarial defect

    International Nuclear Information System (INIS)

    Jung, Ui-Won; Song, Kun-Young; Kim, Chang-Sung; Lee, Yong-Keun; Cho, Kyoo-Sung; Kim, Chong-Kwan; Choi, Seong-Ho

    2007-01-01

    The purpose of this study was to evaluate the effects of a chitosan membrane coated with polylactic and polyglycolic acid (PLGA) on bone regeneration in a rat calvarial defect. Surgical implantation of chitosan membranes resulted in enhanced local bone formation at both 2 and 8 weeks. In conclusion, the chitosan membrane coated with PLGA had a significant potential to induce bone formation in the rat calvarial defect model. Within the selected PLGA dose range and observation intervals, there appeared to be no meaningful differences in bone formation

  14. Electrospun superhydrophobic membranes with unique structures for membrane distillation.

    Science.gov (United States)

    Liao, Yuan; Loh, Chun-Heng; Wang, Rong; Fane, Anthony G

    2014-09-24

    With modest temperature demand, low operating pressure, and high solute rejection, membrane distillation (MD) is an attractive option for desalination, waste treatment, and food and pharmaceutical processing. However, large-scale practical applications of MD are still hindered by the absence of effective membranes with high hydrophobicity, high porosity, and adequate mechanical strength, which are important properties for MD permeation fluxes, stable long-term performance, and effective packing in modules without damage. This study describes novel design strategies for highly robust superhydrophobic dual-layer membranes for MD via electrospinning. One of the newly developed membranes comprises a durable and ultrathin 3-dimensional (3D) superhydrophobic skin and porous nanofibrous support whereas another was fabricated by electrospinning 3D superhydrophobic layers on a nonwoven support. These membranes exhibit superhydrophobicity toward distilled water, salty water, oil-in-water emulsion, and beverages, which enables them to be used not only for desalination but also for other processes. The superhydrophobic dual-layer membrane #3S-N with nanofibrous support has a competitive permeation flux of 24.6 ± 1.2 kg m(-2) h(-1) in MD (feed and permeate temperate were set as 333 and 293 K, respectively) due to the higher porosity of the nanofibrous scaffold. Meanwhile, the membranes with the nonwoven support exhibit greater mechanical strength due to this support combined with better long-term performance because of the thicker 3D superhydrophobic layers. The morphology, pore size, porosity, mechanical properties, and liquid enter pressure of water of these superhydrophobic composite membranes with two different structures are reported and compared with commercial polyvinylidene fluoride membranes.

  15. Journal of Surgical Technique and Case Report: Editorial Policies

    African Journals Online (AJOL)

    Focus and Scope. The aim of Journal of Surgical Technique and Case Report is to advance surgical knowledge and practice by promoting the reporting of innovative and reproducible surgical techniques and illustrative surgical cases on various surgical disciplines. The journal encourages authoritative synthesis of current ...

  16. Innovative hybrid biological reactors using membranes

    International Nuclear Information System (INIS)

    Diez, R.; Esteban-Garcia, A. L.; Florio, L. de; Rodriguez-Hernandez, L.; Tejero, I.

    2011-01-01

    In this paper we present two lines of research on hybrid reactors including the use of membranes, although with different functions: RBPM, biofilm reactors and membranes filtration RBSOM, supported biofilm reactors and oxygen membranes. (Author) 14 refs.

  17. Wrong-Site Surgery, Retained Surgical Items, and Surgical Fires : A Systematic Review of Surgical Never Events.

    Science.gov (United States)

    Hempel, Susanne; Maggard-Gibbons, Melinda; Nguyen, David K; Dawes, Aaron J; Miake-Lye, Isomi; Beroes, Jessica M; Booth, Marika J; Miles, Jeremy N V; Shanman, Roberta; Shekelle, Paul G

    2015-08-01

    Serious, preventable surgical events, termed never events, continue to occur despite considerable patient safety efforts. To examine the incidence and root causes of and interventions to prevent wrong-site surgery, retained surgical items, and surgical fires in the era after the implementation of the Universal Protocol in 2004. We searched 9 electronic databases for entries from 2004 through June 30, 2014, screened references, and consulted experts. Two independent reviewers identified relevant publications in June 2014. One reviewer used a standardized form to extract data and a second reviewer checked the data. Strength of evidence was established by the review team. Data extraction was completed in January 2015. Incidence of wrong-site surgery, retained surgical items, and surgical fires. We found 138 empirical studies that met our inclusion criteria. Incidence estimates for wrong-site surgery in US settings varied by data source and procedure (median estimate, 0.09 events per 10,000 surgical procedures). The median estimate for retained surgical items was 1.32 events per 10,000 procedures, but estimates varied by item and procedure. The per-procedure surgical fire incidence is unknown. A frequently reported root cause was inadequate communication. Methodologic challenges associated with investigating changes in rare events limit the conclusions of 78 intervention evaluations. Limited evidence supported the Universal Protocol (5 studies), education (4 studies), and team training (4 studies) interventions to prevent wrong-site surgery. Limited evidence exists to prevent retained surgical items by using data-matrix-coded sponge-counting systems (5 pertinent studies). Evidence for preventing surgical fires was insufficient, and intervention effects were not estimable. Current estimates for wrong-site surgery and retained surgical items are 1 event per 100,000 and 1 event per 10,000 procedures, respectively, but the precision is uncertain, and the per

  18. Mobile surgical skills education unit: a new concept in surgical training.

    Science.gov (United States)

    Shaikh, Faisal M; Hseino, Hazem; Hill, Arnold D K; Kavanagh, Eamon; Traynor, Oscar

    2011-08-01

    Basic surgical skills are an integral part of surgical training. Simulation-based surgical training offers an opportunity both to trainees and trainers to learn and teach surgical skills outside the operating room in a nonpatient, nonstressed environment. However, widespread adoption of simulation technology especially in medical education is prohibited by its inherent higher cost, limited space, and interruptions to clinical duties. Mobile skills laboratory has been proposed as a means to address some of these limitations. A new program is designed by the Royal College of Surgeons in Ireland (RCSI), in an approach to teach its postgraduate basic surgical trainees the necessary surgical skills, by making the use of mobile innovative simulation technology in their own hospital settings. In this article, authors describe the program and students response to the mobile surgical skills being delivered in the region of their training hospitals and by their own regional consultant trainers.

  19. Hydrogen superpermeable membrane operation under plasma conditions

    International Nuclear Information System (INIS)

    Bacal, M.; Bruneteau, A.M.; Livshits, A.I.; Alimov, V.N.; Notkin, M.E.

    2003-01-01

    The effect of ion bombardment on hydrogen plasma-driven permeation through a superpermeable niobium membrane was investigated. It was found that the increase of membrane temperature and the doping of membrane material with oxygen results in the decrease of ion bombardment effect and in permeability increase. It was demonstrated that membrane decarbonization leads to the formation of a membrane state resistant to sputtering. Possible applications of the membrane resistant to ion bombardment as plasma facing components are considered

  20. Three-Dimensional Printing Surgical Applications.

    Science.gov (United States)

    AlAli, Ahmad B; Griffin, Michelle F; Butler, Peter E

    2015-01-01

    Three-dimensional printing, a technology used for decades in the industrial field, gains a lot of attention in the medical field for its potential benefits. With advancement of desktop printers, this technology is accessible and a lot of research is going on in the medical field. To evaluate its application in surgical field, which may include but not limited to surgical planning, surgical education, implants, and prosthesis, which are the focus of this review. Research was conducted by searching PubMed, Web of science, and other reliable sources. We included original articles and excluded articles based on animals, those more than 10 years old, and those not in English. These articles were evaluated, and relevant studies were included in this review. Three-dimensional printing shows a potential benefit in surgical application. Printed implants were used in patient in a few cases and show successful results; however, longer follow-up and more trials are needed. Surgical and medical education is believed to be more efficient with this technology than the current practice. Printed surgical instrument and surgical planning are also believed to improve with three-dimensional printing. Three-dimensional printing can be a very powerful tool in the near future, which can aid the medical field that is facing a lot of challenges and obstacles. However, despite the reported results, further research on larger samples and analytical measurements should be conducted to ensure this technology's impact on the practice.

  1. Surgical care in the isolated military hospital.

    Science.gov (United States)

    Lukish, J R; Gill, G G; McCoy, T R

    2001-01-01

    To maintain the health of service members and their families throughout the world, the Department of Defense has established several isolated military hospitals (IHs). The operational environment of IHs is such that illness and traumatic injury requiring surgical intervention is common. This study sought to examine the general and orthopedic surgical experience at an IH to determine whether surgical care could be provided in an effective and safe manner. All patients evaluated by the general and orthopedic surgeon at Guantanamo Bay Naval Hospital from October 1, 1998, to April 1, 1999, were included in this study. The following data were retrospectively reviewed: patient demographic data, diagnosis, initial and follow-up care, medical evacuation data, operative procedures, and complications. There were 336 patients who presented for surgical evaluation, resulting in 660 follow-up appointments during the study period. There were 31 medical evacuations (3 emergent). The surgical services performed 122 major operative procedures. There were 58 inpatient admissions. There was 1 death, and surgical complications occurred in 2 patients, for an overall morbidity and mortality of 1.4% and 0.7%, respectively. Our data show that an IH is capable of providing surgical care, including care for traumatic injuries, in a safe manner. This is the first study that provides objective evidence that general and orthopedic surgery at an IH can be provided within the standard of care.

  2. Do psychological variables affect early surgical recovery?

    Directory of Open Access Journals (Sweden)

    Michael N Mavros

    Full Text Available BACKGROUND: Numerous studies have examined the effect of psychological variables on surgical recovery, but no definite conclusion has been reached yet. We sought to examine whether psychological factors influence early surgical recovery. METHODS: We performed a systematic search in PubMed, Scopus and PsycINFO databases to identify studies examining the association of preoperative psychological variables or interventions with objectively measured, early surgical outcomes. RESULTS: We identified 16 eligible studies, 15 of which reported a significant association between at least one psychological variable or intervention and an early postoperative outcome. However, most studies also reported psychological factors not influencing surgical recovery and there was significant heterogeneity across the studies. Overall, trait and state anxiety, state anger, active coping, subclinical depression, and intramarital hostility appeared to complicate recovery, while dispositional optimism, religiousness, anger control, low pain expectations, and external locus of control seemed to promote healing. Psychological interventions (guided relaxation, couple support visit, and psychiatric interview also appeared to favor recovery. Psychological factors unrelated to surgical outcomes included loneliness, perceived social support, anger expression, and trait anger. CONCLUSION: Although the heterogeneity of the available evidence precludes any safe conclusions, psychological variables appear to be associated with early surgical recovery; this association could bear important implications for clinical practice. Large clinical trials and further analyses are needed to precisely evaluate the contribution of psychology in surgical recovery.

  3. Mastoidectomy: anatomical parameters x surgical difficulty

    Directory of Open Access Journals (Sweden)

    Pereira Júnior, Anastácio Rodrigues

    2012-01-01

    Full Text Available Introduction: The lowered temporal meninges and/ or anterior sigmoid sinus are contiditions that can determine surgical difficulties in performing mastoidectomy. Objective: To correlate in the tomography the extent of the prolapse of the sigmoid sinus and of temporal meninges with the surgical difficulty in the mastoidectomy. Method: The tomographic measurements of prolapse sigmoid and of temporal meninges were correlated with the presence or non-presence of the surgical difficulty observed during the mastoidectomy procedure in patients with ostomatoiditis chronic (n=30. Form of study: Contemporary cohort transverse. Results: In 10 patients were observed surgical difficulty distributed as: due to prolapse of the sigmoid sinus (n = 2 or temporal meninges prolapse (n = 7 or both (n = 1. In patients in which the surgical difficulty was due to sigmoid sinus prolapse, the tomography distance of the anterior border of the sigmoid sinus to posterior wall of external auditory canal was lower than 9 mm. In patients in which surgical difficulty was due to temporal meninges prolapse, the tomographic distance to the upper plane of the petrous bone was 7 mm. Conclusion: The computerized tomography distance between the temporal meninges and the upper plane of the petrous bone 7 mm and the distance of the anterior border of the sigmoid sinus to posterior wall of external auditory canal was lower than 9 mm are predictive to the surgical difficulties to perform mastoidectomy.

  4. Surgical management of fibrotic encapsulation of the fluocinolone acetonide implant in CAPN5-associated proliferative vitreoretinopathy

    Directory of Open Access Journals (Sweden)

    Tlucek PS

    2013-06-01

    Full Text Available Paul S Tlucek,1 James C Folk,1 Warren M Sobol,2 Vinit B Mahajan1,3 1Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA; 2Retina Physicians and Surgeons, Dayton, OH, USA; 3Omics Laboratory, University of Iowa, Iowa City, IA, USA Objective: To review fibrosis of fluocinolone acetonide (FA implants in subjects with CAPN5 autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV. Methods: A retrospective case series was assembled from ADNIV patients in which there was fibrotic encapsulation of a fluocinolone acetonide implant. CAPN5 genotypes and surgical repair techniques were reviewed. Results: Two eyes of two ADNIV patients developed a fibrotic capsule over the fluocinolone acetonide implant. Both patients had Stage IV disease. Patient A had a c.731T > C mutation in the CAPN5 gene and patient B had a c.728G > T mutation. The fibrotic membrane was surgically excised and the implant function was restored. Conclusion: The exuberant fibrotic response in later stages of ADNIV may be resistant to local immunosuppression with steroids. Surgical excision of fibrotic membranes over FA implants can reestablish local steroid delivery in cases of severe proliferative vitreoretinopathy. Keywords: autosomal dominant neovascular inflammatory vitreoretinopathy, ADNIV, CAPN5, calpain-5, Retisert, fluocinolone acetonide, fibrotic encapsulation

  5. Membrane manufacture for peptide separations

    KAUST Repository

    Kim, Dooli; Salazar Moya, Octavio Ruben; Nunes, Suzana Pereira

    2016-01-01

    Nanostructured polymeric membranes are key tools in biomedical applications such as hemodialysis, protein separations, in the food industry, and drinking water supply from seawater. Despite of the success in different separation processes, membrane manufacture itself is at risk, since the most used solvents are about to be banned in many countries due to environmental and health issues. We propose for the first time the preparation of polyethersulfone membranes based on dissolution in the ionic liquid 1-ethyl-3-methylimidazolium dimethylphosphate ([EMIM]DEP). We obtained a series of membranes tailored for separation of solutes with molecular weight of 30, 5, 1.3, and 1.25 kg mol-1 with respective water permeances of 140, 65, 30 and 20 Lm-2h-1bar-1. We demonstrate their superior efficiency in the separation of complex mixtures of peptides with molecular weights in the range of 800 to 3500 gmol-1. Furthermore, the thermodynamics and kinetics of phase separation leading to the pore formation in the membranes were investigated. The rheology of the solutions and the morphology of the prepared membranes were examed and compared to those of polyethersulfone in organic solvents currently used for membrane manufacture.

  6. FAS grafted superhydrophobic ceramic membrane

    Energy Technology Data Exchange (ETDEWEB)

    Lu Jun [School of Material Science and Engineering, Jingdezhen Ceramic Institute, 333001 Jingdezhen (China); Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, CAS, 1295 DingXi Road, Shanghai 200050 (China); Yu Yun, E-mail: yunyush@mail.sic.ac.cn [Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, CAS, 1295 DingXi Road, Shanghai 200050 (China); Zhou Jianer [School of Material Science and Engineering, Jingdezhen Ceramic Institute, 333001 Jingdezhen (China); Song Lixin; Hu Xingfang [Key Laboratory of Inorganic Coating Materials, Shanghai Institute of Ceramics, CAS, 1295 DingXi Road, Shanghai 200050 (China); Larbot, Andre [Institut Europeen des Membranes, UMR 5635-CNRS, ENSCM, UMII, 1919 Route de Mende 34293, Montpellier Cedex 5 (France)

    2009-08-30

    The hydrophobic properties of {gamma}-Al{sub 2}O{sub 3} membrane have been obtained by grafting fluoroalkylsilane (FAS) on the surface of the membrane. The following grafting parameters were studied: the eroding time of the original membrane, the grafting time, the concentration of FAS solution and the multiplicity of grafting. Hydrophobicity of the membranes was characterized by contact angle (CA) measurement. The thermogravimetric analysis (TGA) was used to investigate the weight loss process (25-800 deg. C) of the fluoroalkylsilane grafted on Al{sub 2}O{sub 3} powders under different grafting conditions. The morphologies of the membranes modified under different parameters were examined by field emission scanning electron microscopy (FE-SEM) and the surface roughness (Ra) was measured using white light interferometers. A needle-like structure was observed on the membrane surface after modification, which causes the change of Ra. On the results above, we speculated a model to describe the reaction between FAS and {gamma}-Al{sub 2}O{sub 3} membrane surface as well as the formed surface morphology.

  7. FAS grafted superhydrophobic ceramic membrane

    Science.gov (United States)

    Lu, Jun; Yu, Yun; Zhou, Jianer; Song, Lixin; Hu, Xingfang; Larbot, Andre

    2009-08-01

    The hydrophobic properties of γ-Al 2O 3 membrane have been obtained by grafting fluoroalkylsilane (FAS) on the surface of the membrane. The following grafting parameters were studied: the eroding time of the original membrane, the grafting time, the concentration of FAS solution and the multiplicity of grafting. Hydrophobicity of the membranes was characterized by contact angle (CA) measurement. The thermogravimetric analysis (TGA) was used to investigate the weight loss process (25-800 °C) of the fluoroalkylsilane grafted on Al 2O 3 powders under different grafting conditions. The morphologies of the membranes modified under different parameters were examined by field emission scanning electron microscopy (FE-SEM) and the surface roughness (Ra) was measured using white light interferometers. A needle-like structure was observed on the membrane surface after modification, which causes the change of Ra. On the results above, we speculated a model to describe the reaction between FAS and γ-Al 2O 3 membrane surface as well as the formed surface morphology.

  8. Membrane manufacture for peptide separations

    KAUST Repository

    Kim, Dooli

    2016-06-07

    Nanostructured polymeric membranes are key tools in biomedical applications such as hemodialysis, protein separations, in the food industry, and drinking water supply from seawater. Despite of the success in different separation processes, membrane manufacture itself is at risk, since the most used solvents are about to be banned in many countries due to environmental and health issues. We propose for the first time the preparation of polyethersulfone membranes based on dissolution in the ionic liquid 1-ethyl-3-methylimidazolium dimethylphosphate ([EMIM]DEP). We obtained a series of membranes tailored for separation of solutes with molecular weight of 30, 5, 1.3, and 1.25 kg mol-1 with respective water permeances of 140, 65, 30 and 20 Lm-2h-1bar-1. We demonstrate their superior efficiency in the separation of complex mixtures of peptides with molecular weights in the range of 800 to 3500 gmol-1. Furthermore, the thermodynamics and kinetics of phase separation leading to the pore formation in the membranes were investigated. The rheology of the solutions and the morphology of the prepared membranes were examed and compared to those of polyethersulfone in organic solvents currently used for membrane manufacture.

  9. Ultrastructure of Reissner's membrane in the rabbit

    DEFF Research Database (Denmark)

    Qvortrup, K.; Rostgaard, Jørgen; Bretlau, P.

    1994-01-01

    Anatomy, Reissner's membrane, electron microscopy, tubulocisternal endoplasmic reticulum, subsurface cisterns, rabbit......Anatomy, Reissner's membrane, electron microscopy, tubulocisternal endoplasmic reticulum, subsurface cisterns, rabbit...

  10. Nanofluidics : Silicon for the perfect membrane

    NARCIS (Netherlands)

    van den Berg, Albert; Wessling, Matthias

    2007-01-01

    Newly developed ultrathin silicon membranes can filter and separate molecules much more effectively than conventional polymer membranes. Many applications, of economic and medical significance, stand to benefit.

  11. Beard reconstruction: A surgical algorithm.

    Science.gov (United States)

    Ninkovic, M; Heidekrueger, P I; Ehrl, D; von Spiegel, F; Broer, P N

    2016-06-01

    Facial defects with loss of hair-bearing regions can be caused by trauma, infection, tumor excision, or burn injury. The presented analysis evaluates a series of different surgical approaches with a focus on male beard reconstruction, emphasizing the role of tissue expansion of regional and free flaps. Locoregional and free flap reconstructions were performed in 11 male patients with 14 facial defects affecting the hair-bearing bucco-mandibular or perioral region. In order to minimize donor-site morbidity and obtain large amounts of thin, pliable, hair-bearing tissue, pre-expansion was performed in five of 14 patients. Eight of 14 patients were treated with locoregional flap reconstructions and six with free flap reconstructions. Algorithms regarding pre- and intraoperative decision making are discussed and long-term (mean follow-up 1.5 years) results analyzed. Major complications, including tissue expander infection with the need for removal or exchange, partial or full flap loss, occurred in 0% (0/8) of patients with locoregional flaps and in 17% (1/6) of patients undergoing free flap reconstructions. Secondary refinement surgery was performed in 25% (2/8) of locoregional flaps and in 67% (4/6) of free flaps. Both locoregional and distant tissue transfers play a role in beard reconstruction, while pre-expansion remains an invaluable tool. Paying attention to the presented principles and considering the significance of aesthetic facial subunits, range of motion, aesthetics, and patient satisfaction were improved long term in all our patients while minimizing donor-site morbidity. Copyright © 2016 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  12. Surgical management of radiation enterocolitis

    International Nuclear Information System (INIS)

    Ieda, Katsuyuki; Katsumi, Masaharu; Ura, Shinzoh

    1980-01-01

    We reviewed 17 cases of severe radiation enterocolitis caused by tele-cobalt treatment for pelvic malignancies. They consisted of six males and nine females, ranging from 32 to 77 years old. The duration between the completion of radiation and the onset of symptoms varied from two months to ten years. Only two cases of them were treated conservatively and the other 15 cases were managed surgically. Six cases of the latter underwent an urgent surgery because of severe obstructive symptoms. Totally, 19 injuries to the intestine were revealed. The ileum was involved in eight patients, the rectum in seven and the sigmoid colon in four. Operative procedures carried out were intestinal resection with primary anastomosis in seven, colostomy alone in six and bypass operation in three. The resected segments of the ileum measured 40 cm long in two and 70 cm, 90 cm and 100 cm long in three respectively and the resected segments of the colon measured 15 cm and 45 cm long respectively. Three out of the seven cases with bowel resection were reconstructed with Gambee's single layer anastomosis and four with Albert-Lembert's two layer anastomosis. Type of anastomosis was end-to-end in six and end-to-side in one. Three cases underwent bypass operations because the injured intestines were densely adhered to the surroundings. Only one minor leakage occurred in seven primary anastomosis. Radiation doses ranged from 3000 to 9300 R. There was no relation between doses and severity of damage, clinical symptoms and site of injuries. There was no malignant findings around the damaged intestine. Many of the literatures report a high anastomotic leak in radiation enterocolitis, primary anastomosis can be carried out more safely if wide resection and reasonable anastomosis are performed. (author)

  13. Surgical patient selection and counseling.

    Science.gov (United States)

    Ziegelmann, Matt; Köhler, Tobias S; Bailey, George C; Miest, Tanner; Alom, Manaf; Trost, Landon

    2017-08-01

    The objectives of patient selection and counseling are ultimately to enhance successful outcomes. However, the definition for success is often narrowly defined in published literature (ability to complete surgery, complications, satisfaction) and fails to account for patient desires and expectations, temporal changes, natural history of underlying diseases, or independent validation. Factors associated with satisfaction and dissatisfaction are often surgery-specific, although correlation with pre-operative expectations, revisions, and complications are common with most procedures. The process of appropriate patient selection is determined by the integration of patient and surgeon factors, including psychological capacity to handle unsatisfactory results, baseline expectations, complexity of case, and surgeon volume and experience. Using this model, a high-risk scenario includes one in which a low-volume surgeon performs a complex case in a patient with limited psychological capacity and high expectations. In contrast, a high-volume surgeon performing a routine case in a male with low expectations and abundant psychiatric reserve is more likely to achieve a successful outcome. To further help identify patients who are at high risk for dissatisfaction, a previously published mnemonic is recommended: CURSED Patient (compulsive/obsessive, unrealistic, revision, surgeon shopping, entitled, denial, and psychiatric). Appropriate patient counseling includes setting appropriate expectations, reviewing the potential and anticipated risks of surgery, post-operative instruction to limit complications, and long-term follow-up. As thorough counseling is often a time-consuming endeavor, busy practices may elect to utilize various resources including educational materials, advanced practice providers, or group visits, among others. The consequences for poor patient selection and counseling may range from poor surgical outcomes and patient dissatisfaction to lawsuits, loss of

  14. [Quality of surgical continuing education in Germany].

    Science.gov (United States)

    Ansorg, J; Hassan, I; Fendrich, V; Polonius, M J; Rothmund, M; Langer, P

    2005-03-11

    One of the reasons for young doctors to leave the clinical work to go abroad or into non-clinical fields is insufficient quality of training under bad circumstances. Aim of the study was to evaluate the surgical training in Germany from the viewpoint of the residents. A questionnaire was prepared by residents and consultants and approved by the German surgical societies (Deutsche Gesellschaft fur Chirurgie und Berufsverband der Deutschen Chirurgen). It was sent to surgical residents between June 2003 and June 2004, published in "Der Chirurg BDC" and distributed among residents taking part in courses conducted by the BDC. It could be answered anonymously by email, mail or online. The questionnaire was sent back by 584 surgical residents (about 30 % of all). 58 % of the residents declared that they finished the training in the intended time (6 years). Rotation-systems as part of a structured residency program existed for 43 %. Standard surgical procedures were discussed or explained before the procedure in only 46 %. 61 % of the residents were not satisfied with the teaching assistance by their clinical teachers in the OR. Only 33 % had regular talks with the Chief about their progress in surgical training. 18 % of residents felt, that the hospital is interested in their progress in training. Indication-conferences took place in 52 % and mortality-conferences in only 20 % of programs. Regular seminars on recent issues took place in 62 %, and 61 % of residents did not get financial support to attend congresses. 36 % of residents had to use their holidays to attend congresses. Surgical training structures are not well established in about 50 % of the training hospitals from where we got answers to our survey. The training potential of daily surgical work is not used appropriately. It is therefore imperative to develop guidelines for surgical training, the use of log-books and rotation-programs.

  15. Isolation of plasma membrane-associated membranes from rat liver.

    Science.gov (United States)

    Suski, Jan M; Lebiedzinska, Magdalena; Wojtala, Aleksandra; Duszynski, Jerzy; Giorgi, Carlotta; Pinton, Paolo; Wieckowski, Mariusz R

    2014-02-01

    Dynamic interplay between intracellular organelles requires a particular functional apposition of membrane structures. The organelles involved come into close contact, but do not fuse, thereby giving rise to notable microdomains; these microdomains allow rapid communication between the organelles. Plasma membrane-associated membranes (PAMs), which are microdomains of the plasma membrane (PM) interacting with the endoplasmic reticulum (ER) and mitochondria, are dynamic structures that mediate transport of proteins, lipids, ions and metabolites. These structures have gained much interest lately owing to their roles in many crucial cellular processes. Here we provide an optimized protocol for the isolation of PAM, PM and ER fractions from rat liver that is based on a series of differential centrifugations, followed by the fractionation of crude PM on a discontinuous sucrose gradient. The procedure requires ∼8-10 h, and it can be easily modified and adapted to other tissues and cell types.

  16. Diffusion of Integral Membrane Proteins in Protein-Rich Membranes

    DEFF Research Database (Denmark)

    Javanainen, Matti; Martinez-Seara, Hector; Metzler, Ralf

    2017-01-01

    of being protein-poor, native cell membranes are extremely crowded with proteins. On the basis of extensive molecular simulations, we here demonstrate that protein crowding of the membrane at physiological levels leads to deviations from the SD relation and to the emergence of a stronger Stokes......-like dependence D ∝ 1/R. We propose that this 1/R law mainly arises due to geometrical factors: smaller proteins are able to avoid confinement effects much better than their larger counterparts. The results highlight that the lateral dynamics in the crowded setting found in native membranes is radically different......The lateral diffusion of embedded proteins along lipid membranes in protein-poor conditions has been successfully described in terms of the Saffman-Delbrück (SD) model, which predicts that the protein diffusion coefficient D is weakly dependent on its radius R as D ∝ ln(1/R). However, instead...

  17. Graphene oxide improves the biocompatibility of collagen membranes in an in vitro model of human primary gingival fibroblasts.

    Science.gov (United States)

    De Marco, Patrizia; Zara, Susi; De Colli, Marianna; Radunovic, Milena; Lazović, Vladimir; Ettorre, Valeria; Di Crescenzo, Antonello; Piattelli, Adriano; Cataldi, Amelia; Fontana, Antonella

    2017-09-13

    Commercial collagen membranes are used in oral surgical procedures as scaffolds for bone deposition in guided bone regeneration. Here, we have enriched them with graphene oxide (GO) via a simple non-covalent functionalization, exploiting the capacity of oxygenated carbon functional moieties of GO to interact through hydrogen bonding with collagen. In the present paper, the GO-coated membranes have been characterized in terms of stability, nano-roughness, biocompatibility and induction of inflammatory response in human primary gingival fibroblast cells. The obtained coated membranes are demonstrated not to leak GO in the bulk solution, and to change some features of the membrane, such as stiffness and adhesion between the membrane and the atomic force microscopy (AFM) tip. Moreover, the presence of GO increases the roughness and the total surface exposed to the cells, as demonstrated by AFM analyses. The obtained material is biocompatible, and does not induce inflammation in the tested cells.

  18. An exploratory study with an adaptive continuous intravenous furosemide regimen in neonates treated with extracorporeal membrane oxygenation

    NARCIS (Netherlands)

    M.M.J. van der Vorst (Maria); J. den Hartigh (Jan); E.D. Wildschut (Enno); D. Tibboel (Dick); J. Burggraaf (Jacobus)

    2007-01-01

    textabstractIntroduction: The objective of the present study was to explore a continuous intravenous furosemide regimen that adapts to urine output in neonates treated with extracorporeal membrane oxygenation (ECMO). Methods: Seven neonates admitted to a paediatric surgical intensive care unit for

  19. Amniotic Membrane Transplantation

    Directory of Open Access Journals (Sweden)

    Alireza Baradaran-Rafii

    2008-12-01

    Full Text Available

    The past decade has witnessed the revival of amniotic membrane transplantation (AMT in ophthalmology. The importance of amniotic membrane lies in its ability to reduce inflammation and scarring, enhance epithelialization and wound healing, and in its antimicrobial properties. Amniotic membrane has recently been used as a substrate for culturing limbal stem cells for transplantation. It has also been used extensively in corneal conditions such as neurotrophic ulcers, persistent epithelial defects, shield ulcers, microbial keratitis, band keratopathy, bullous keratopathy, and following photorefractive keratectomy and chemical injuries. Other indications for AMT include ocular surface reconstruction surgery for conjunctival pathologies such as squamous neoplasia, pterygium, and symblepharon. In this review we describe the basic structure and properties of amniotic membrane, its preparation process and its applications in ophthalmology.

  1. Assessment of Surgical Skills and Competency.

    Science.gov (United States)

    Bhatti, Nasir I

    2017-10-01

    Evaluation of surgical skills and competency are important aspects of the medical education process. Measurable and reproducible methods of assessment with objective feedback are essential components of surgical training. Objective Structured Assessment of Technical Skills (OSATS) is widely used across the medical specialties and otolaryngology-specific tools have been developed and validated for sinus and mastoid surgery. Although assessment of surgical skills can be time-consuming and requires human and financial resources, new evaluation methods and emerging technology may alleviate these barriers while also improving data collection practices. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Simulators and virtual reality in surgical education.

    Science.gov (United States)

    Chou, Betty; Handa, Victoria L

    2006-06-01

    This article explores the pros and cons of virtual reality simulators, their abilities to train and assess surgical skills, and their potential future applications. Computer-based virtual reality simulators and more conventional box trainers are compared and contrasted. The virtual reality simulator provides objective assessment of surgical skills and immediate feedback further to enhance training. With this ability to provide standardized, unbiased assessment of surgical skills, the virtual reality trainer has the potential to be a tool for selecting, instructing, certifying, and recertifying gynecologists.

  3. Wastewater treatment by nanofiltration membranes

    Science.gov (United States)

    Mulyanti, R.; Susanto, H.

    2018-03-01

    Lower energy consumption compared to reverse osmosis (RO) and higher rejection compared to ultrafiltration make nanofiltration (NF) membrane get more and more attention for wastewater treatment. NF has become a promising technology not only for treating wastewater but also for reusing water from wastewater. This paper presents various application of NF for wastewater treatments. The factors affecting the performance of NF membranes including operating conditions, feed characteristics and membrane characteristics were discussed. In addition, fouling as a severe problem during NF application is also presented. Further, future prospects and challenges of NF for wastewater treatments are explained.

  4. Development of silica RO membranes

    International Nuclear Information System (INIS)

    Ikeda, Ayumi; Kawamoto, Takashi; Matsuyama, Emi; Utsumi, Keisuke; Nomura, Mikihiro; Sugimoto, Masaki; Yoshikawa, Masato

    2012-01-01

    Silica based membranes have been developed by using a counter diffusion CVD method. Effects of alkyl groups in the silica precursors and deposition temperatures had investigated in order to control pore sizes of the silica membranes. In this study, this type of a silica membrane was applied for RO separation. Effects of silica sources, deposition temperatures and post treatments had been investigated. Tetramethoxysilane (TMOS), Ethyltrimethoxysilane (ETMOS) and Phenyltrimethoxysilane (PhTMOS) were used as silica precursors. A counter diffusion CVD method was carried out for 90 min at 270 - 600degC on γ-alumina capillary substrates (effective length: 50 mm, φ: 4 nm: NOK Co.). O 3 or O 2 was introduced into the inside of the substrate at the O 2 rate of 0.2 L min -1 . Ion beam irradiation was carried out for a post treatment using Os at 490 MeV for 1.0 x 10 10 ions cm -2 or 3.0 x 10 10 ions cm -2 . Single gas permeance was measured by using H 2 , N 2 and SF 6 . RO tests were employed at 3.0 or 5.4 MPa for 100 mg L -1 of feed NaCl solution. First, effects of the silica sources were investigated. The total fluxes increased by increasing N 2 permeance through the silica membrane deposited by ETMOS. The maximum NaCl rejection was 28.2% at 12.2 kg m -2 h -1 of the total flux through the membrane deposited at 270degC. N 2 permeance was 9.6 x 10 -9 mol m -2 s -1 Pa -1 . While, total fluxes through the membrane deposited by using PhTMOS were smaller than those through the ETMOS membranes. The phenyl groups for the PhTMOS membrane must be important for the hydrophobic properties through the membrane. Next, effects of ion beam irradiation were tested for the TMOS membranes. Water is difficult to permeate through the TMOS membranes due to the low N 2 permeance through the membrane (3.1 x 10 -11 mol m -2 s -1 Pa -1 ). N 2 permeance increased to 7.3 x 10 -9 mol m -2 s -1 Pa -1 by the irradiation. Irradiation amounts had little effects on N 2 permeance. However, NaCl rejections

  5. Experimental approaches to membrane thermodynamics

    DEFF Research Database (Denmark)

    Westh, Peter

    2009-01-01

    Thermodynamics describes a system on the macroscopic scale, yet it is becoming an important tool for the elucidation of many specific molecular aspects of membrane properties. In this note we discuss this application of thermodynamics, and give a number of examples on how thermodynamic measurements...... have contributed to the understanding of specific membrane phenomena. We mainly focus on non-specific interactions of bilayers and small molecules (water and solutes) in the surrounding solvent, and the changes in membrane properties they bring about. Differences between thermodynamic...

  6. Membrane modules for building ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Kistler, K.R.; Cussler, E.L.

    2002-01-01

    Hollow fibre and flat sheet membranes with an interfacially polymerized coating of polyamide have a permeance for water vapour of about 0.16 m sec{sup -1}. These membranes can serve as a basis for building ventilation which provides fresh air while recovering about 70% of the specific heat and 60% of the latent heat. Because these membranes are selective for water vapour, the air is exhausted with internal pollutants like carbon monoxide, formaldehyde, and radon. The expense of the ventilator should be recovered in reduced heating costs in about three years. (Author)

  7. Sensing voltage across lipid membranes

    Science.gov (United States)

    Swartz, Kenton J.

    2009-01-01

    The detection of electrical potentials across lipid bilayers by specialized membrane proteins is required for many fundamental cellular processes such as the generation and propagation of nerve impulses. These membrane proteins possess modular voltage-sensing domains, a notable example being the S1-S4 domains of voltage-activated ion channels. Ground-breaking structural studies on these domains explain how voltage sensors are designed and reveal important interactions with the surrounding lipid membrane. Although further structures are needed to fully understand the conformational changes that occur during voltage sensing, the available data help to frame several key concepts that are fundamental to the mechanism of voltage sensing. PMID:19092925

  8. Memcomputing with membrane memcapacitive systems

    International Nuclear Information System (INIS)

    Pershin, Y V; Traversa, F L; Ventra, M Di

    2015-01-01

    We show theoretically that networks of membrane memcapacitive systems—capacitors with memory made out of membrane materials—can be used to perform a complete set of logic gates in a massively parallel way by simply changing the external input amplitudes, but not the topology of the network. This polymorphism is an important characteristic of memcomputing (computing with memories) that closely reproduces one of the main features of the brain. A practical realization of these membrane memcapacitive systems, using, e.g., graphene or other 2D materials, would be a step forward towards a solid-state realization of memcomputing with passive devices. (paper)

  9. Perforated schneiderian membrane repair during sinus augmentation in conjunction with immediate implant placement

    Directory of Open Access Journals (Sweden)

    K Hameed Fathima

    2014-01-01

    Full Text Available Dental implant associated rehabilitation of the posterior maxilla poses unique challenge owing to the presence of pneumatized sinuses and atrophied alveolar bone. Sinus augmentation procedure to manage expanded sinuses frequently results in membrane tear resulting in unfavorable stabilization of the graft and associated bone regeneration. Simultaneous implant placement during sinus augmentation procedures frequently requires a minimal alveolar bone height, which when not present forces clinician to defer implant placement resulting in extended treatment duration and multiple surgical appointments. The present case report is about a piezosurgery assisted lateral wall osteotomy approach for sinus augmentation associated with membrane repair with simultaneous implant placement in the posterior maxilla.

  10. Injectible candidate sealants for fetal membrane repair: Bonding and toxicity in vitro

    Science.gov (United States)

    Bilic, Grozdana; Brubaker, Carrie; Messersmith, Phillip B.; Mallik, Ajit S.; Quinn, Thomas M.; Haller, Claudia; Done, Elisa; Gucciardo, Leonardo; Zeisberger, Steffen M.; Zimmermann, Roland; Deprest, Jan; Zisch, Andreas H.

    2010-01-01

    Objective This study was undertaken to test injectible surgical sealants that are biocompatible with fetal membranes, eventually for closure of iatrogenic membrane defects. Study Design Dermabond, Histoacryl, Tissucol fibrin glue, and three types of in situ forming poly(ethylene glycol)-based polymer hydrogels were tested for acute toxicity upon direct contact with fetal membranes for 24h. For determination of elution toxicity, extracts of sealants were incubated on amnion cell cultures for 72h. Bonding and toxicity was assessed through morphological and/or biochemical analysis. Results Extracts of all adhesives were non-toxic for cultured cells. However, only Tissucol and one type of poly(ethylene glycol)-based hydrogel, mussel-mimetic tissue adhesive, showed efficient, non-disruptive, non-toxic bonding to fetal membranes. Mussel-mimetic tissue adhesive applied over membrane defects created with a 3.5 mm trocar accomplished leak-proof closure that withstood membrane stretch in an in vitro model. Conclusion A synthetic hydrogel-type tissue adhesive emerged as potential sealing modality for iatrogenic membrane defects that merits further evaluation in vivo. PMID:20096254

  11. INTRASURGICAL MICROSCOPE-INTEGRATED SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY-ASSISTED MEMBRANE PEELING.

    Science.gov (United States)

    Falkner-Radler, Christiane I; Glittenberg, Carl; Gabriel, Max; Binder, Susanne

    2015-10-01

    To evaluate microscope-integrated intrasurgical spectral domain optical coherence tomography during macular surgery in a prospective monocenter study. Before pars plana vitrectomy and before, during, and after membrane peeling, 512 × 128 macular cube scans were performed using a Carl Zeiss Meditec Cirrus high-definition OCT system adapted to the optical pathway of a Zeiss OPMI VISU 200 surgical microscope and compared with retinal staining. The study included 51 patients with epiretinal membranes, with 8 of those having additional lamellar macular holes, 11 patients with vitreomacular traction, and 8 patients with full-thickness macular holes. Intraoperative spectral domain optical coherence tomography allowed performing membrane peeling without using retinal dyes in 40% of cases (28 of 70 patients). No residual membranes were found in 94.3% of patients (66 of 70 patients) in intrasurgical spectral domain optical coherence tomography and subsequent (re)staining. In patients with vitreomacular traction, intrasurgical spectral domain optical coherence tomography scans facilitated decisions on the need for an intraocular tamponade after membrane peeling. Intraoperative spectral domain optical coherence tomography was comparable with retinal dyes in confirming success after membrane peeling. However, the visualization of flat membranes was better after staining.

  12. Facile fabrication of aloe vera containing PCL nanofibers for barrier membrane application.

    Science.gov (United States)

    Carter, Princeton; Rahman, Shekh M; Bhattarai, Narayan

    2016-01-01

    Guided tissue regeneration (GTR) is a widely used method in dental surgical procedures that utilizes a barrier membrane to exclude migration of epithelium and ensure repopulation of periodontal ligament cells at the sites having insufficient gingiva. Commercial GTR membranes are typically composed of synthetic polymers that have had mild clinical success mostly because of their lack of proper bioactivity and appropriate degradation profile. In this study, a natural polymer, aloe vera was blended with polycaprolactone (PCL) to create nanofibrous GTR membranes by electrospinning. Aloe vera has proven anti-inflammatory properties and enhances the regeneration of periodontium tissues. PCL, a synthetic polymer, is well known to produce miscible polyblends nanofibers with natural polymers. Nanofibrous membranes with varying composition of PCL to aloe vera were fabricated, and several physicochemical and biological properties, such as fiber morphology, wettability, chemical structure, mechanical strength, and cellular compatibility of the membranes were analyzed. PCL/aloe vera membranes with ratios from 100/00 to 70/30 showed good uniformity in fiber morphology and suitable mechanical properties, and retained the integrity of their fibrous structure in aqueous solutions. Experimental results, using cell viability assay and cell attachment observation, showed that the nanofibrous membranes support 3T3 cell viability and could be a potential candidate for GTR therapy.

  13. Surgical Site Infection Rate and Risk Factors among Obstetric Cases ...

    African Journals Online (AJOL)

    2009-04-01

    Among surgical patients in obstetrics, Surgical Site Infections were the most ... for delivery from April 1, 2009 to March 31, 2010 in obstetric ward of the Hospital. ... applying improved surgical techniques and improving infection prevention ...

  14. Vacuum membrane distillation of liquid desiccants Utilizing Hollow Fiber Membranes

    KAUST Repository

    Lefers, Ryan; Srivatsa Bettahalli, N.M.; Fedoroff, Nina V.; Nunes, Suzana Pereira; Leiknes, TorOve

    2018-01-01

    This paper documents the testing of a vacuum membrane distillation system intended for use with liquid desiccants. Liquid desiccants offer the possibility for low-energy, ambient temperature dehumidification. Effective desalination and purification of diluted desiccants outputs two important products: a concentrated desiccant for reuse in dehumidification and fresh water. In this study, vacuum membrane distillation was used in the laboratory to purify diluted liquid desiccants. Calcium chloride and magnesium chloride were the desiccants selected for testing. Desiccant solutions were pumped through the lumens of poly(vinylidene fluoride) (PVDF) hollow fiber membranes at varying feed inlet temperatures, solution velocity rates and vacuum set points during membrane distillation. An average flux of 8 kg m-2 h-1 was obtained using 30 wt% magnesium chloride solution at a temperature of 50 °C while applying vacuum to achieve 25 mbar absolute pressure on the air side of the membrane. The results are promising for the development of a full-scale vacuum membrane distillation process for desiccant solution regeneration and fresh water recovery. In addition, the recovered condensate was of sufficient quality for use in agricultural irrigation or drinking water.

  15. Vacuum membrane distillation of liquid desiccants Utilizing Hollow Fiber Membranes

    KAUST Repository

    Lefers, Ryan

    2018-01-31

    This paper documents the testing of a vacuum membrane distillation system intended for use with liquid desiccants. Liquid desiccants offer the possibility for low-energy, ambient temperature dehumidification. Effective desalination and purification of diluted desiccants outputs two important products: a concentrated desiccant for reuse in dehumidification and fresh water. In this study, vacuum membrane distillation was used in the laboratory to purify diluted liquid desiccants. Calcium chloride and magnesium chloride were the desiccants selected for testing. Desiccant solutions were pumped through the lumens of poly(vinylidene fluoride) (PVDF) hollow fiber membranes at varying feed inlet temperatures, solution velocity rates and vacuum set points during membrane distillation. An average flux of 8 kg m-2 h-1 was obtained using 30 wt% magnesium chloride solution at a temperature of 50 °C while applying vacuum to achieve 25 mbar absolute pressure on the air side of the membrane. The results are promising for the development of a full-scale vacuum membrane distillation process for desiccant solution regeneration and fresh water recovery. In addition, the recovered condensate was of sufficient quality for use in agricultural irrigation or drinking water.

  16. The Role of Ion Exchange Membranes in Membrane Capacitive Deionisation.

    Science.gov (United States)

    Hassanvand, Armineh; Wei, Kajia; Talebi, Sahar; Chen, George Q; Kentish, Sandra E

    2017-09-14

    Ion-exchange membranes (IEMs) are unique in combining the electrochemical properties of ion exchange resins and the permeability of a membrane. They are being used widely to treat industrial effluents, and in seawater and brackish water desalination. Membrane Capacitive Deionisation (MCDI) is an emerging, energy efficient technology for brackish water desalination in which these ion-exchange membranes act as selective gates allowing the transport of counter-ions toward carbon electrodes. This article provides a summary of recent developments in the preparation, characterization, and performance of ion exchange membranes in the MCDI field. In some parts of this review, the most relevant literature in the area of electrodialysis (ED) is also discussed to better elucidate the role of the ion exchange membranes. We conclude that more work is required to better define the desalination performance of the proposed novel materials and cell designs for MCDI in treating a wide range of feed waters. The extent of fouling, the development of cleaning strategies, and further techno-economic studies, will add value to this emerging technique.

  17. SAGES TAVAC safety and effectiveness analysis: da Vinci ® Surgical System (Intuitive Surgical, Sunnyvale, CA).

    Science.gov (United States)

    Tsuda, Shawn; Oleynikov, Dmitry; Gould, Jon; Azagury, Dan; Sandler, Bryan; Hutter, Matthew; Ross, Sharona; Haas, Eric; Brody, Fred; Satava, Richard

    2015-10-01

    The da Vinci(®) Surgical System (Intuitive Surgical, Sunnyvale, CA, USA) is a computer-assisted (robotic) surgical system designed to enable and enhance minimally invasive surgery. The Food and Drug Administration (FDA) has cleared computer-assisted surgical systems for use by trained physicians in an operating room environment for laparoscopic surgical procedures in general, cardiac, colorectal, gynecologic, head and neck, thoracic and urologic surgical procedures. There are substantial numbers of peer-reviewed papers regarding the da Vinci(®) Surgical System, and a thoughtful assessment of evidence framed by clinical opinion is warranted. The SAGES da Vinci(®) TAVAC sub-committee performed a literature review of the da Vinci(®) Surgical System regarding gastrointestinal surgery. Conclusions by the sub-committee were vetted by the SAGES TAVAC Committee and SAGES Executive Board. Following revisions, the document was evaluated by the TAVAC Committee and Executive Board again for final approval. Several conclusions were drawn based on expert opinion organized by safety, efficacy, and cost for robotic foregut, bariatric, hepatobiliary/pancreatic, colorectal surgery, and single-incision cholecystectomy. Gastrointestinal surgery with the da Vinci(®) Surgical System is safe and comparable, but not superior to standard laparoscopic approaches. Although clinically acceptable, its use may be costly for select gastrointestinal procedures. Current data are limited to the da Vinci(®) Surgical System; further analyses are needed.

  18. Treatment of intrabony defects with resorbable materials, non-resorbable materials and flap debridement.

    Science.gov (United States)

    Zybutz, M D; Laurell, L; Rapoport, D A; Persson, G R

    2000-03-01

    Different types of barriers are used in guided tissue regenerative procedures. This prospective study compared resorbable citric acid ester softened polylactic acid membranes (RM) and non-resorbable expanded polytetrafluoroethylene (ePTFE) barriers (NRM) in GTR treatment of intrabony defects. 29 subjects were randomly assigned to the RM group or NRM group. Each patient received one GTR procedure. An open flap debridement (FD) was performed at another site 2 weeks later to evaluate healing potential. Clinical treatment outcomes were finally evaluated 12 months after surgery for changes of pocket depth PD, probing attachment level PAL, and probing bone level PBL, and radiographically for bone change using standardised radiographs. No differences in healing patters after surgery were found between patients in the 2 study groups as evaluated from the FD surgical procedures. NRM treated sites showed less signs of post-surgical inflammation during the 1st 4 weeks of healing than did RM treated sites (p<0.05). GTR-treated defects in the RM group, initially 7.0+/-2.2 mm deep, showed PD reduction of 3.3+/-2.2 mm, PAL gain of 2.4+/-1.8 mm, PBL gain of 2.4+/-3.7 mm (28%) and a radiographic bone fill of 2.3+/-2.4 mm. Defects treated with the NRM exhibited PD reduction of 3.1+/-2.1 mm, PAL gain of 2.4+/-0.8 mm, PBL gain of 2.2+/-1.7 mm (25%) and a radiographic bone fill of 3.3+/-2.2 mm. All improvements were statistically significant (p<0.01) but there was no difference between RM and NRM treatments for any of the efficacy variables. The results of this study indicated that there was no clinically significant difference in treatment outcomes following GTR treatment of intrabony defects with citric acid ester softened polylactic acid membranes as compared to ePTFE barriers. The overall mean inter-proximal vertical bone defect fill at 12 months as assessed from intra-oral radiographs was 44% of the original mean defect depth. Thus, no clinically significant difference in

  19. Layered plasma polymer composite membranes

    Science.gov (United States)

    Babcock, Walter C.

    1994-01-01

    Layered plasma polymer composite fluid separation membranes are disclosed, which comprise alternating selective and permeable layers for a total of at least 2n layers, where n is .gtoreq.2 and is the number of selective layers.

  20. Lysosomal degradation of membrane lipids.

    Science.gov (United States)

    Kolter, Thomas; Sandhoff, Konrad

    2010-05-03

    The constitutive degradation of membrane components takes place in the acidic compartments of a cell, the endosomes and lysosomes. Sites of lipid degradation are intralysosomal membranes that are formed in endosomes, where the lipid composition is adjusted for degradation. Cholesterol is sorted out of the inner membranes, their content in bis(monoacylglycero)phosphate increases, and, most likely, sphingomyelin is degraded to ceramide. Together with endosomal and lysosomal lipid-binding proteins, the Niemann-Pick disease, type C2-protein, the GM2-activator, and the saposins sap-A, -B, -C, and -D, a suitable membrane lipid composition is required for degradation of complex lipids by hydrolytic enzymes. Copyright 2009 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  1. Membrane Trafficking and Vesicle Fusion

    Indian Academy of Sciences (India)

    IAS Admin

    protein and the data can be cor- related with cellular .... these mutant cells under the electron microscope and found a large number of ... trans-Golgi network and early ..... Arrows represent the flow of membrane traffic: black arrows – antero-.

  2. Surgical Excision Of A Craniopharynginoma By Transcallosal ...

    African Journals Online (AJOL)

    complaints included: polydipsia and polyuria in one case, progressive hypopsia in the second case; headache in the third case; and hormonal manifestations in the .... Intraventricular craniopharyngiomas: topographical classification and surgical approach selection based on an extensive overview. Acta Neurochir , 2004 ,.

  3. Surgical manipulation of mammalian embryos in vitro.

    Science.gov (United States)

    Naruse, I; Keino, H; Taniguchi, M

    1997-04-01

    Whole-embryo culture systems are useful in the fields of not only embryology but also teratology, toxicology, pharmacology, and physiology. Of the many advantages of whole-embryo culture, we focus here on the surgical manipulation of mammalian embryos. Whole-embryo culture allows us to manipulate mammalian embryos, similarly to fish, amphibian and avian embryos. Many surgical experiments have been performed in mammalian embryos in vitro. Such surgical manipulation alters the destiny of morphogenesis of the embryos and can answer many questions concerning developmental issues. As an example of surgical manipulation using whole-embryo culture systems, one of our experiments is described. Microsurgical electrocauterization of the deep preaxial mesodermal programmed cell death zone (fpp) in the footplate prevented the manifestation of polydactyly in genetic polydactyly mouse embryos (Pdn/Pdn), in which fpp was abolished.

  4. Surgical Competence: Assessing, Acquiring, Maintaining, and ...

    African Journals Online (AJOL)

    Hp 630 Dual Core

    Emeritus Professor of Paediatric Surgery, Royal Aberdeen Children s ... Formerly Vice President of the Royal College of Surgeons of Edinburgh ... where a highly critical if not toxic climate of low tolerance of surgical failure, with judicial,.

  5. Liability exposure for surgical robotics instructors.

    Science.gov (United States)

    Lee, Yu L; Kilic, Gokhan; Phelps, John Y

    2012-01-01

    Surgical robotics instructors provide an essential service in improving the competency of novice gynecologic surgeons learning robotic surgery and advancing surgical skills on behalf of patients. However, despite best intentions, robotics instructors and the gynecologists who use their services expose themselves to liability. The fear of litigation in the event of a surgical complication may reduce the availability and utility of robotics instructors. A better understanding of the principles of duty of care and the physician-patient relationship, and their potential applicability in a court of law likely will help to dismantle some concerns and uncertainties about liability. This commentary is not meant to discourage current and future surgical instructors but to raise awareness of liability issues among robotics instructors and their students and to recommend certain preventive measures to curb potential liability risks. Published by Elsevier Inc.

  6. Non-surgical therapy of Peyronie's disease.

    Science.gov (United States)

    Taylor, Frederick L; Levine, Laurence A

    2008-01-01

    The present paper provides a review of the available non-surgical treatments for Peyronie's disease (PD). A review of published literature on oral, intralesional, external energy and iontophoresis therapies for PD was performed, and the published results of available treatment options reviewed. The authors recommendations for appropriate non-surgical management of PD are provided. Although there are many published reports that show the efficacy of non-surgical therapies for PD, there is a lack of large scale, multicenter controlled clinical trials, which makes treatment recommendations difficult. Careful review of the literature does suggest that there are treatment options that make scientific sense and appear to stabilize the disease process, reduce deformity, and improve function. Offering no treatment at all will encourage our patients to pursue alternative treatments, which might do harm, and misses the opportunity to do some good. Clearly further work is necessary to develop safe and effective non-surgical treatments for PD.

  7. Surgical Apgar Score Predicts Postoperative Complications in ...

    African Journals Online (AJOL)

    complications were determined during the thirty day post operative period. ... An ideal model to predict postoperative complications ... their SAS for purposes of risk stratification; high risk. (0-4), medium .... surgical audit (9,14). Serial monitoring ...

  8. Mechanical ventilation strategies for the surgical patient

    NARCIS (Netherlands)

    Schultz, Marcus J.; Abreu, Marcelo Gama de; Pelosi, Paolo

    2015-01-01

    Purpose of review To summarize clinical evidence for intraoperative ventilation settings, which could protect against postoperative pulmonary complications (PPCs) in surgical patients with uninjured lungs. Recent findings There is convincing evidence for protection against PPCs by low tidal volumes:

  9. Surgical treatment of endometriosis before gamete intrafallopian ...

    African Journals Online (AJOL)

    Abstract. Objective. To determine whether active pelvic endometriosis impairs the efficacy of GIFT (gamete intrafallopian transfer) and whether prior surgical treatment of endometriosis improves the efficacy of GIFT. Design. Matched controlled retrospective study. Setting. University-based assisted reproduction programme.

  10. Abdominal Compartment Syndrome in Surgical Patients

    African Journals Online (AJOL)

    abdominal hypertension and abdominal compartment syndrome, affect ... timely surgical intervention is crucial. Key words: .... On the second postoperative day, he was noted to be restless ... Although surgery is very effective in managing ACS.

  11. Surgical Apgar Score Predicts Post- Laparatomy Complications

    African Journals Online (AJOL)

    calculated Surgical Apgar Scores for 152 patients during a 6-month study ... major postoperative complications and/or death within. 30 days of ... respond to and control hemodynamic changes during a ... abdominal injury (18.42%). Intestinal ...

  12. Right Diaphragm Spontaneous Rupture: A Surgical Approach

    Directory of Open Access Journals (Sweden)

    Duilio Divisi

    2011-01-01

    Full Text Available We present a case of spontaneous rupture of the diaphragm, characterized by nonspecific symptoms. The rapid diagnosis and appropriate surgical approach led to a positive resolution of the pathology.

  13. Posterior fossa meningioma (surgical experiences) | Moussa ...

    African Journals Online (AJOL)

    Symptoms included headache (75%), cerebellar manifestations (60%), cranial nerve affection (40%) and hearing disturbances (15%). Most of the cases (50%) were cerebellopontine angle meningioma while the least (5%) were foramen magnum meningioma. Surgical approaches used included retrosigmoid approach ...

  14. Hemorrhoidectomy - making sense of the surgical options

    Science.gov (United States)

    Yeo, Danson; Tan, Kok-Yang

    2014-01-01

    While debate continues as to which is the best surgical method for the treatment of hemorrhoids, none of the currently available surgical methods approach the ideal surgical option, which is one that is effective while being safe and painless. In reality, the less painful the procedure, the more likely it is to be associated with recurrence post-op. Where hemorrhoids surgery is concerned, there isn’t a “one size fits all” option. Most of the randomized controlled trials performed to date include hemorrhoids of various grades and with a focus on only comparing surgical methods while failing to stratify the outcomes according to the grade of hemorrhoid. We believe that surgery needs to be tailored not only to the grade of the hemorrhoids, but also to the size, circumferential nature of the disease, and prevailing symptomatology. PMID:25493010

  15. Clinicopathological review of surgically removed appendix in ...

    African Journals Online (AJOL)

    Babatunde M. Duduyemi

    2014-09-17

    Sep 17, 2014 ... It is the most common cause of acute surgical abdomen worldwide. ... Faculty of Medicine. Alexandria Journal of Medicine ... and sex distribution, nature of clinical signs and symptoms as .... radiological investigations.

  16. [Surgical site infections: antibiotic prophylaxis in surgery].

    Science.gov (United States)

    Asensio, Angel

    2014-01-01

    Surgical site infections (SSI) are very common, and represent more than 20% of all hospital-acquired infections. SSIs are associated with a higher mortality, as well as to an extended hospital stay and costs, depending on the surgical procedure and type of SSI. Advances in control practices for these infections include improvement in operating room ventilation, sterilization methods, barriers, and surgical techniques, as well as in surgical antimicrobial prophylaxis. For the latter, the antimicrobial agent should: be active against the most common pathogens, be administered in an appropriate dosage and in a time frame to ensure serum and tissue concentrations over the period of potential contamination, be safe, and be administered over the shortest effective time period to minimize adverse events, development of resistances, and cost. Copyright © 2013 Elsevier España, S.L. All rights reserved.

  17. An overview of pre-surgical evaluation

    Directory of Open Access Journals (Sweden)

    Kurupath Radhakrishnan

    2014-01-01

    Full Text Available The success of an epilepsy surgery program depends upon the early identification of potential surgical candidates and selecting from them, ideal candidates for surgery, who are destined to have a post-operative seizure-free outcome without any unacceptable neurological deficits. Since epilepsy surgery centers in resource-poor countries will lack the full range of state-of-the-art technologies usually available in resource-rich countries to perform pre-surgical evaluation, cost-effectively utilization of the locally available investigative facilities to select the surgical candidates becomes challenging. In the present era of rapid electronic communications and telemedicine, it has become possible for epilepsy surgery centers to pool their technological and human resources and to partner with centers nationally and internationally in implementing pre-surgical evaluation strategies.

  18. Surgical treatment for ectopic atrial tachycardia.

    Science.gov (United States)

    Graffigna, A; Vigano, M; Pagani, F; Salerno, G

    1992-08-01

    Atrial tachycardia is an infrequent but potentially dangerous arrhythmia which often determines cardiac enlargement. Surgical ablation of the arrhythmia is effective and safe, provided a careful atrial mapping is performed and the surgical technique is tailored to the individual focus location. Eight patients underwent surgical ablation of ectopic atrial tachycardia between 1977 and 1990. Different techniques were adopted for each patient according to the anatomical location of the focus and possibly associated arrhythmias. Whenever possible, a closed heart procedure was chosen. In 1 patient a double focal origin was found and treated by separate procedures. In 1 patient with ostium secundum atrial septal defect and atrial flutter, surgical isolation of the right appendage and the ectopic focus was performed. In all patients ectopic atrial tachycardia was ablated with maintenance of the sinoatrial and atrioventricular nodal function as well as internodal conduction. In follow-up up to December 1991, no recurrency was recorded.

  19. Surgical Oncology Nursing: Looking Back, Looking Forward.

    Science.gov (United States)

    Crane, Patrick C; Selanders, Louise

    2017-02-01

    To provide a historical perspective in the development of oncology nursing and surgical oncology as critical components of today's health care system. Review of the literature and Web sites of key organizations. The evolution of surgical oncology nursing has traversed a historical journey from that of a niche subspecialty of nursing that had very little scientific underpinning, to a highly sophisticated discipline within a very short time. Nursing continues to contribute its expertise to the encyclopedic knowledge base of surgical oncology and cancer care, which have helped improve the lives of countless patients and families who have had to face the difficulties of this diagnosis. An understanding of the historical context for which a nursing specialty such as surgical oncology nursing evolves is critical to gaining an appreciation for the contributions of nursing. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Factors influencing incident reporting in surgical care.

    Science.gov (United States)

    Kreckler, S; Catchpole, K; McCulloch, P; Handa, A

    2009-04-01

    To evaluate the process of incident reporting in a surgical setting. In particular: the influence of event outcome on reporting behaviour; staff perception of surgical complications as reportable events. Anonymous web-based questionnaire survey. General Surgical Department in a UK teaching hospital. Of 203 eligible staff, 55 (76.4%) doctors and 82 (62.6%) nurses participated. Knowledge and use of local reporting system; propensity to report incidents which vary by outcome (harm, no harm, harm prevented); propensity to report surgical complications; practical and psychological barriers to reporting. Nurses were significantly more likely to know of the local reporting system and to have recently completed a report than doctors. The level of harm (F(1.8,246) = 254.2, pvs 53%, z = 4.633, psystems.

  1. Recent technological advancements in laparoscopic surgical instruments

    Science.gov (United States)

    Subido, Edwin D. C.; Pacis, Danica Mitch M.; Bugtai, Nilo T.

    2018-02-01

    Laparoscopy was a progressive step to advancing surgical procedures as it minimised the scars left on the body after surgery, compared to traditional open surgery. Many years later, single-incision laparoscopic surgery (SILS) was created where, instead of having multiple incisions, only one incision is made or multiple small incisions in one location. SILS, or laparoendoscopic single-site surgery (LESS), may produce lesser scars but drawbacks for the surgeons are still present. This paper aims to present related literature of the recent technological developments in laparoscopic tools and procedure particularly in the vision system, handheld instruments. Tech advances in LESS will also be shown. Furthermore, this review intends to give an update on what has been going on in the surgical robot market and state which companies are interested and are developing robotic systems for commercial use to challenge Intuitive Surgical's da Vinci Surgical System that currently dominates the market.

  2. Oxygen Transport Ceramic Membranes

    Energy Technology Data Exchange (ETDEWEB)

    S. Bandopadhyay; N. Nagabhushana; X.-D Zhou; Q. Cai; J. Yang; W.B. Yelon; W.J. James; H.U. Anderson; Alan Jacobson; C.A. Mims

    2004-05-01

    The present quarterly report describes some of the investigations on the structural properties of dense OTM bars provided by Praxair and studies on newer composition of Ti doped LSF. In this report, in situ neutron diffraction was used to characterize the chemical and structural properties of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} (here after as L2SF55T) specimen, which was subject to measurements of neutron diffraction from room temperature to 900 C in N{sub 2}. Space group of R3c was found to result in a better refinement and is used in this study. The difference for crystal structure, lattice parameters and local crystal chemistry for LSFT nearly unchanged when gas environment switched from air to N{sub 2}. Stable crack growth studies on Dense OTM bars provided by Praxair were done at room temperature in air. A bridge-compression fixture was fabricated to achieve stable pre-cracks from Vickers indents. Post fracture evaluation indicated stable crack growth from the indent and a regime of fast fracture. Post-fracture X-ray data of the OTM fractured at 1000 C in environment were refined by FullProf code and results indicate a distortion of the parent cubic perovskite to orthorhombic structure with reduced symmetry. TGA-DTA studies on the post-fracture samples also indicated residual effect arising from the thermal and stress history of the samples. The thermal and chemical expansion of La{sub 0.2}Sr{sub 0.8}Fe{sub 0.55}Ti{sub 0.45}O{sub 3-{delta}} were studied at 800 {le} T {le} 1000 C and at {approx} 1 x 10{sup -15} {le} pO{sub 2} {le} 0.21 atm. The thermal expansion coefficient of the sample was calculated from the dilatometric analysis in the temperature range between room temperature and 1200 C in air. A series of isotope transients under air separation mode (small gradient) were completed on the membrane of LSCrF-2828 at 900 C. Low pO{sub 2} atmospheres based on with CO-CO{sub 2} mixtures have also been admitted to the delivery side of

  3. 42 CFR 482.51 - Condition of participation: Surgical services.

    Science.gov (United States)

    2010-10-01

    ... of medicine or osteopathy. (2) Licensed practical nurses (LPNs) and surgical technologists (operating... performing surgery in accordance with the competencies of each practitioner. The surgical service must...

  4. Gas separation membrane module assembly

    Science.gov (United States)

    Wynn, Nicholas P [Palo Alto, CA; Fulton, Donald A [Fairfield, CA

    2009-03-31

    A gas-separation membrane module assembly and a gas-separation process using the assembly. The assembly includes a set of tubes, each containing gas-separation membranes, arranged within a housing. The housing contains a tube sheet that divides the space within the housing into two gas-tight spaces. A permeate collection system within the housing gathers permeate gas from the tubes for discharge from the housing.

  5. Membranes in Lithium Ion Batteries

    Science.gov (United States)

    Yang, Min; Hou, Junbo

    2012-01-01

    Lithium ion batteries have proven themselves the main choice of power sources for portable electronics. Besides consumer electronics, lithium ion batteries are also growing in popularity for military, electric vehicle, and aerospace applications. The present review attempts to summarize the knowledge about some selected membranes in lithium ion batteries. Based on the type of electrolyte used, literature concerning ceramic-glass and polymer solid ion conductors, microporous filter type separators and polymer gel based membranes is reviewed. PMID:24958286

  6. Membranes in Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Junbo Hou

    2012-07-01

    Full Text Available Lithium ion batteries have proven themselves the main choice of power sources for portable electronics. Besides consumer electronics, lithium ion batteries are also growing in popularity for military, electric vehicle, and aerospace applications. The present review attempts to summarize the knowledge about some selected membranes in lithium ion batteries. Based on the type of electrolyte used, literature concerning ceramic-glass and polymer solid ion conductors, microporous filter type separators and polymer gel based membranes is reviewed.

  7. Static and Dynamic Membrane Structures

    Directory of Open Access Journals (Sweden)

    Sergiu Ivanov

    2012-10-01

    Full Text Available While originally P systems were defined to contain multiset rewriting rules, it turned out that considering different types of rules may produce important results, such as increasing the computational power of the rules. This paper focuses on factoring out the concept of a membrane structure out of various P system models with the goal of providing useful formalisations. Both static and dynamic membrane structures are considered.

  8. Graft infections after surgical aortic reconstructions

    OpenAIRE

    Berger, P.

    2015-01-01

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

  9. Clinical and Surgical Anatomy of the Neck

    OpenAIRE

    Fernández Russo, Gustavo A.H.

    2012-01-01

    Introduction: to bring relevance on morphological details pertaining to medical and surgical applicability and demonstrate its value as an unavoidable mainstay for diagnosis and mangement of head and neck pathology.Materials and method: a. standarized dissections, of preserved adult human corpses, to obtain anatomical pieces for teaching purposes in school of medicine, axial slices and its comparative study with computed tomography (CT) images. b.application of normalized surgical techniques...

  10. Non-surgical treatment of esophageal achalasia

    Science.gov (United States)

    Annese, Vito; Bassotti, Gabrio

    2006-01-01

    Esophageal achalasia is an infrequent motility disorder characterized by a progressive stasis and dilation of the oesophagus; with subsequent risk of aspiration, weight loss, and malnutrition. Although the treatment of achalasia has been traditionally based on a surgical approach, especially with the introduction of laparoscopic techniques, there is still some space for a medical approach. The present article reviews the non-surgical therapeutic options for achalasia. PMID:17007039

  11. Review of emerging surgical robotic technology.

    Science.gov (United States)

    Peters, Brian S; Armijo, Priscila R; Krause, Crystal; Choudhury, Songita A; Oleynikov, Dmitry

    2018-04-01

    The use of laparoscopic and robotic procedures has increased in general surgery. Minimally invasive robotic surgery has made tremendous progress in a relatively short period of time, realizing improvements for both the patient and surgeon. This has led to an increase in the use and development of robotic devices and platforms for general surgery. The purpose of this review is to explore current and emerging surgical robotic technologies in a growing and dynamic environment of research and development. This review explores medical and surgical robotic endoscopic surgery and peripheral technologies currently available or in development. The devices discussed here are specific to general surgery, including laparoscopy, colonoscopy, esophagogastroduodenoscopy, and thoracoscopy. Benefits and limitations of each technology were identified and applicable future directions were described. A number of FDA-approved devices and platforms for robotic surgery were reviewed, including the da Vinci Surgical System, Sensei X Robotic Catheter System, FreeHand 1.2, invendoscopy E200 system, Flex® Robotic System, Senhance, ARES, the Single-Port Instrument Delivery Extended Research (SPIDER), and the NeoGuide Colonoscope. Additionally, platforms were reviewed which have not yet obtained FDA approval including MiroSurge, ViaCath System, SPORT™ Surgical System, SurgiBot, Versius Robotic System, Master and Slave Transluminal Endoscopic Robot, Verb Surgical, Miniature In Vivo Robot, and the Einstein Surgical Robot. The use and demand for robotic medical and surgical platforms is increasing and new technologies are continually being developed. New technologies are increasingly implemented to improve on the capabilities of previously established systems. Future studies are needed to further evaluate the strengths and weaknesses of each robotic surgical device and platform in the operating suite.

  12. Trends in the Surgical Correction of Gynecomastia

    OpenAIRE

    Brown, Rodger H.; Chang, Daniel K.; Siy, Richard; Friedman, Jeffrey

    2015-01-01

    Gynecomastia refers to the enlargement of the male breast due to a proliferation of ductal, stromal, and/or fatty tissue. Although it is a common condition affecting up to 65% of men, not all cases require surgical intervention. Contemporary surgical techniques in the treatment of gynecomastia have become increasingly less invasive with the advent of liposuction and its variants, including power-assisted and ultrasound-assisted liposuction. These techniques, however, have been largely limited...

  13. Spinal intramedullary ependymoma: surgical approaches and outcome.

    Science.gov (United States)

    Borges, Lawrence F

    2018-02-01

    Intramedullary ependymomas are uncommon tumors that can occur within the medullary substance of the spinal cord. Despite this difficult location, they are typically benign tumors that can most often be removed completely with an acceptable surgical risk. Therefore, the recommended management approach is usually surgical excision. This review will consider the historical context in which surgeons began treating these tumors and then review the more recent literature that guides their current management.

  14. Endotoxins in surgical instruments of hip arthroplasty

    OpenAIRE

    Goveia, Vania Regina; Mendoza, Isabel Yovana Quispe; Guimarães, Gilberto Lima; Ercole, Flavia Falci; Couto, Bráulio Roberto Gonçalves Marinho; Leite, Edna Marilea Meireles; Stoianoff, Maria Aparecida Resende; Ferreira, José Antonio Guimarães

    2016-01-01

    Abstract OBJECTIVE To investigate endotoxins in sterilized surgical instruments used in hip arthroplasties. METHOD A descriptive exploratory study conducted in a public teaching hospital. Six types of surgical instruments were selected, namely: acetabulum rasp, femoral rasp, femoral head remover, chisel box, flexible bone reamer and femoral head test. The selection was based on the analysis of the difficulty in removing bone and blood residues during cleaning. The sample was made up of 60...

  15. Motivation factors of surgical profile nurses work

    OpenAIRE

    Namajuškaitė, Vaida

    2006-01-01

    The aim of the study – investigate the motivation factors of surgical profile nurses work. The objectives of the study: 1. To investigate of satisfaction with work, to identify the motivation positive factors, emotional exhaustion of nurses, which are working in the surgical profile departments and operating-theaters. 2. To investigate negative factors (emotional exhaustion, salary, nursing load). 3. To give the offers for the main problems solutions. Hypothesis – the nurses m...

  16. Non-surgical treatment of esophageal achalasia

    OpenAIRE

    Annese, Vito; Bassotti, Gabrio

    2006-01-01

    Esophageal achalasia is an infrequent motility disorder characterized by a progressive stasis and dilation of the oesophagus; with subsequent risk of aspiration, weight loss, and malnutrition. Although the treatment of achalasia has been traditionally based on a surgical approach, especially with the introduction of laparoscopic techniques, there is still some space for a medical approach. The present article reviews the non-surgical therapeutic options for achalasia.

  17. Surgical Pathology Bootcamp: A Military Experience

    Science.gov (United States)

    2018-03-17

    CAP 2018, Vancouver, British Columbia, Canada, March 17-23, 2018 14. ABSTRACT Surgical Pathology Bootcamp: A Military Experience Nathaniel Smith...REPORT TYPE 3. DATES COVERED (From - To) 17/03/2018 poster 03/17/2018-03/23/2018 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Surgical Pathology ...or its Components. Background A common complaint among pathology department faculty is the variable medical knowledge and histological experience

  18. Approach to Pediatric Patients during Surgical Interventions

    OpenAIRE

    Seher Ünver; Meltem Yıldırım

    2013-01-01

    A child’s surgical period usually contains unpleasant and difficult experiences, for the child and the parents. The child in this period experiences greater anxiety and distress. On the other hand, pediatric patients have complex states that directly effects their perioperative care during. Because their perioperative care includes not only the knowledge of general surgical procedure and care of a patient in the operating room. It also includes the specific understanding of a child’s airway, ...

  19. Surgical treatment for medically refractory myasthenic blepharoptosis

    OpenAIRE

    Shimizu, Yusuke; Suzuki,Shigeaki; Nagasao,Tomohisa; Ogata,Hisao; Yazawa,Masaki; Suzuki,Norihiro; Kishi,Kazuo

    2014-01-01

    Yusuke Shimizu,1 Shigeaki Suzuki,2 Tomohisa Nagasao,1 Hisao Ogata,1 Masaki Yazawa,1 Norihiro Suzuki,2 Kazuo Kishi1 1Department of Plastic and Reconstructive Surgery, 2Department of Neurology, Keio University School of Medicine, Tokyo, JapanPurpose: Currently, only a few reports have recommended surgery as a suitable treatment for blepharoptosis associated with myasthenia gravis. The present study aims to introduce our surgical criteria, surgical options, outcomes, and precautions for medicall...

  20. Advances in surgical treatment of chronic pancreatitis.

    Science.gov (United States)

    Ni, Qingqiang; Yun, Lin; Roy, Manish; Shang, Dong

    2015-02-08

    The incidence of chronic pancreatitis (CP) is between 2 and 200 per 100,000 persons and shows an increasing trend year by year. India has the highest incidence of CP in the world at approximately 114 to 200 per 100,000 persons. The incidence of CP in China is approximately 13 per 100,000 persons. The aim of this review is to assist surgeons in managing patients with CP in surgical treatment. We conducted a PubMed search for "chronic pancreatitis" and "surgical treatment" and reviewed relevant articles. On the basis of our review of the literature, we found that CP cannot be completely cured. The purpose of surgical therapy for CP is to relieve symptoms, especially pain; to improve the patient's quality of life; and to treat complications. Decompression (drainage), resection, neuroablation and decompression combined with resection are commonly used methods for the surgical treatment of CP. Before developing a surgical regimen, surgeons should comprehensively evaluate the patient's clinical manifestations, auxiliary examination results and medical history to develop an individualized surgical treatment regimen.