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Sample records for tissue defect including

  1. Tetralogy of Fallot with restrictive ventricular septal defect by accessory tricuspid leaflet tissue

    OpenAIRE

    Mahipat Raj Soni; Deepak A. Bohara; Ajay U. Mahajan; Pratap J. Nathani

    2012-01-01

    In tetralogy of Fallot septal defect is usually large because of malalignment of outlet septum, restrictive defect has been reported rarely. We present a case of tetralogy of Fallot with accessory tricuspid leaflet tissue restricting ventricular septal defect. The report includes echocardiographic and catheter images of this rare presentation of tetralogy of Fallot.

  2. Repair of osteochondral defects with allogeneic tissue engineered cartilage implants.

    Science.gov (United States)

    Schreiber, R E; Ilten-Kirby, B M; Dunkelman, N S; Symons, K T; Rekettye, L M; Willoughby, J; Ratcliffe, A

    1999-10-01

    The objective of this study was to evaluate the effect of allogeneic tissue engineered cartilage implants on healing of osteochondral defects. Rabbit chondrocytes were cultured in monolayer, then seeded onto biodegradable, three-dimensional polyglycolic acid meshes. Cartilage constructs were cultured hydrodynamically to yield tissue with relatively more (mature) or less (immature) hyalinelike cartilage, as compared with adult rabbit articular cartilage. Osteochondral defects in the patellar grooves of both stifle joints either were left untreated or implanted with allogeneic tissue engineered cartilage. Histologic samples from in and around the defect sites were examined 3, 6, 9, and 12, and 24 months after surgery. By 9 months after surgery, defects sites treated with cartilage implants contained significantly greater amounts of hyalinelike cartilage with high levels of proteoglycan, and had a smooth, nonfibrillated articular surface as compared to untreated defects. In contrast, the repair tissue formed in untreated defects had fibrillated articular surfaces, significant amounts of fibrocartilage, and negligible proteoglycan. These differences between treated and untreated defects persisted through 24 months after surgery. The results of this study suggest that the treatment of osteochondral lesions with allogenic tissue engineered cartilage implants may lead to superior repair tissue than that found in untreated osteochondral lesions.

  3. Hard tissue augmentation for alveolar defects before implant placement

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    Mutia Rochmawati

    2017-08-01

    Full Text Available Background. Often when planning implant therapy, there is a need to augment or  replace  bone  that  has  been  lost. The alveolar defects may occur as a result of tooth loss due to extraction, advanced periodontal diseases or trauma, long term use of removable appliances, dehiscence and fenestration defects, developmental defects/clefts, congenitally missing teeth and odontogenic cysts and tumors. Insufficient bone volume can be brought about by hard tissue augmentation. This techniques have led to increased predictability in reconstruction of alveolar ridge defects and functional implant placement. Purpose. To describe the methods of hard tissue augmentation which can be done with block grafts (autografts and allografts, particulate grafts (cortical and cancellous, xenografts, or synthetic materials. Review. The reconstruction of a normal alveolar housing, in height and width, is imperative to achieve a harmonious balance between biology, function, and aesthetics. Depending on the size and morphology of the defect, horizontal or vertical, various augmentation procedures can be used. Soft tissue management is a critical aspect of hard tissue augmentation procedures. Incisions, reflection, and manipulation should be designed to optimize blood supply and wound closure. The design and management of mucoperiosteal flaps must consider the increased dimensions of the ridge after augmentation as well as esthetics and approximation of the wound margins. The surgical procedure needs to be executed with utmost care to preserve the maximum vascularity to the flap and minimize tissue injury. Conclusion. Alveolar ridge defects can be classified by using Seibert’s classification or HVC System. The treatment of alveolar ridge defect before implant placement can be done with hard tissue augmentation.

  4. [Inconformity between soft tissue defect and bony defect in incomplete cleft palate].

    Science.gov (United States)

    Zhou, Xia; Ma, Lian

    2014-12-01

    To evaluate the inconformity between soft tissue defect and bony defect by observing the cleft extent of palate with complete secondary palate bony cleft in incomplete cleft palate patient. The patients with incomplete cleft palate treated in Hospital of Stomatology Peking University from July 2012 to June 2013 were reviewed, of which 75 cases with complete secondary palate bony cleft were selected in this study. The CT scan and intraoral photograph were taken before operation. The patients were classified as four types according to the extent of soft tissue defect. Type 1: soft tissue defect reached incisive foremen region, Type 2 was hard and soft cleft palate, Type 3 soft cleft palate and Type 4 submucous cleft palate. Type 1 was defined as conformity group (CG). The other three types were defined as inconformity group (ICG) and divided into three subgroups (ICG-I), (ICG-II) and (ICG-III). Fifty-seven patients were in ICG group, and the rate of inconformity was 76% (57/75). The percentage of ICG-I, ICG-II and ICG-III was 47% (27/57), 23% (13/57) and 30% (17/57), respevtively. There are different types of soft tissue deformity with complete secondary palate bony cleft. The inconformity between soft tissue and hard tissue defect exits in 3/4 of isolated cleft palate patients.

  5. Guided tissue regeneration for periodontal infra-bony defects.

    Science.gov (United States)

    Needleman, I G; Worthington, H V; Giedrys-Leeper, E; Tucker, R J

    2006-04-19

    Conventional treatment of destructive periodontal (gum) disease arrests the disease but does not usually regain the bone support or connective tissue lost in the disease process. Guided tissue regeneration (GTR) is a surgical procedure that specifically aims to regenerate the periodontal tissues when the disease is advanced and could overcome some of the limitations of conventional therapy. To assess the efficacy of GTR in the treatment of periodontal infra-bony defects measured against conventional surgery (open flap debridement (OFD)) and factors affecting outcomes. We conducted an electronic search of the Cochrane Oral Health Group Trials Register, MEDLINE and EMBASE up to April 2004. Handsearching included Journal of Periodontology, Journal of Clinical Periodontology, Journal of Periodontal Research and bibliographies of all relevant papers and review articles up to April 2004. In addition, we contacted experts/groups/companies involved in surgical research to find other trials or unpublished material or to clarify ambiguous or missing data and posted requests for data on two periodontal electronic discussion groups. Randomised, controlled trials (RCTs) of at least 12 months duration comparing guided tissue regeneration (with or without graft materials) with open flap debridement for the treatment of periodontal infra-bony defects. Furcation involvements and studies specifically treating aggressive periodontitis were excluded. Screening of possible studies and data extraction was conducted independently. The methodological quality of studies was assessed in duplicate using individual components and agreement determined by Kappa scores. Methodological quality was used in sensitivity analyses to test the robustness of the conclusions. The Cochrane Oral Health Group statistical guidelines were followed and the results expressed as mean differences (MD and 95% CI) for continuous outcomes and risk ratios (RR and 95% CI) for dichotomous outcomes calculated using

  6. Reconstruction of complicated skull base defects utilizing free tissue transfer.

    Science.gov (United States)

    Djalilian, Hamid R; Gapany, Markus; Levine, Samuel C

    2002-11-01

    We managed five patients with large skull base defects complicated by complex infections with microvascular free tissue transfer. The first patient developed an infection, cerebrospinal fluid (CSF) leak, and meningitis after undergoing a translabyrinthine resection of an acoustic neuroma. The second patient had a history of a gunshot wound to the temporal bone, with a large defect and an infected cholesteatoma that caused several episodes of meningitis. The third through the fifth patients had persistent CSF leakage and infection refractory to conventional therapy. In all cases prior attempts of closure with fat grafts or regional flaps had failed. Rectus abdominis myofascial free flap, radial forearm free flap or a gracilis muscle free flap was used after debridement of the infected cavities. The CSF leaks, local infections, and meningitis were controlled within a week. In our experience, microvascular free tissue provides the necessary bulk of viable, well-vascularized tissue, which not only assures a mechanical seal but also helps clear the local infection.

  7. Management of peri-implant soft tissue defect with connective tissue graft - A case report

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    Mohinder Panwar

    2017-01-01

    Full Text Available The use of dental implants to replace missing and nonrestorable teeth has increased significantly in the past two decades. The health of peri-implant tissues plays an important role in the long-term success of dental implants. Soft tissue dehiscence around dental implants has frequently been reported which may lead to poor oral hygiene, plaque accumulation, inflamed gingiva, compromised esthetics, and further progression to peri-implantitis. The coverage of exposed implants is aimed to provide adequate keratinized tissue around dental implant. Complete coverage of mucosal defect around the dental implants is still a challenging prospect. This case report describes correction of soft tissue defect and building up of keratinized tissue in relation to implant in the maxillary right first premolar region with subepithelial connective tissue graft along with coronally advanced flap.

  8. Outcome of reconstruction of cutaneous limb defects in dogs using hygroscopic "self-inflating" tissue expanders.

    Science.gov (United States)

    De Lorenzi, M; Swan, M C; Easter, C; Chanoit, G P A

    2018-02-01

    To describe the placement of self-inflating tissue expanders and clinical outcomes in 12 consecutive cases of reconstruction of distal cutaneous limb defects in dogs. Cases of distal cutaneous limb defect were divided into three groups based on the location of the placement of the self-inflating tissue expanders: Group A (n=4): on, or proximal to, the elbow and stifle; Group B (n=4): distal to the elbow or stifle and proximal to the carpus or tarsus; and Group C (n=4): distal to the carpus or tarsus. Owner satisfaction and clinical outcome were documented. Thirteen cases were originally included, but one was excluded because of incomplete follow-up. In one case, the self-inflating tissue expanders were removed before expansion started. A mean of five expanders were implanted per dog (range 2 to 9). Devices were removed after a mean of 24 days (range 13 to 42 days). Primary closure was achieved in eight of 11 cases, including all cases from Group A and 75% and 33% of cases from Groups B and C, respectively. All incompletely reconstructed defects or areas of wound dehiscence healed by second intention. Eight of 12 owners were satisfied. Self-inflating tissue expanders can be used as an alternative for the reconstruction of limb defects in dogs in which direct primary closure would otherwise not be achievable. Defects below the carpus and tarsus are more challenging to treat with this method. © 2017 British Small Animal Veterinary Association.

  9. Implementation of Water Bolus in Patient with Large Tissue Defect

    International Nuclear Information System (INIS)

    Park, Hyo Kuk; Kim, Joo Ho; Lee, Sang Kyu; Yoon, Jong Won; Cho, Jeong Hee; Kim, Dong Wook

    2006-01-01

    To demonstrate that water bolus in the patient surface can decrease the dose inhomogeneity by patient surface large tissue defect when the surface is in an electron-beam field. And We tried to find a easy way to water control. To demonstrate the use of water bolus in the irregular surface clinically, the case of a patient with myxofibrosarcoma of the chest wall who was treated with electrons. We obtained dose distribution using missing tissue option of PINACLE 6.2b (ADAC, USA). We fabricate a Mev-green for water bolus in patient with defect of tissue. Then put the water bolus which is vinyl packed water into the designed Mev-green. We performed CT scan with CT-simulator. Three-dimensional (3D) dose distributions with and without water bolus in the large irregular chest wall were calculated for a representative patient. Resulting dose distributions and dose-volume histograms of water bolus were compared with missing tissue option and non bolus plans. We fabricate a new water control device. Controlled Water bolus markedly decrease the dose heterogeneity, and minimizes normal tissue exposure caused by the surface irregularities of the chest wall mass. In the test case, The non bolus plan has a maximum target dose of 132%. After applying water bolus, the maximum target dose has been reduced substantially to 110.4%. The maximum target dose was reduced by 21.6% using this technique. The results showed that controlled water bolus could significantly improve the dose homogeneity in the PTV for patients treated with electron therapy using water control device. This technique may reduce the incidence of normal organ complications that occur after electron-beam therapy in irregular surface. And our new device shows handiness of water control.

  10. Defective regulation of adipose tissue autophagy in obesity.

    Science.gov (United States)

    Nuñez, C E; Rodrigues, V S; Gomes, F S; Moura, R F de; Victorio, S C; Bombassaro, B; Chaim, E A; Pareja, J C; Geloneze, B; Velloso, L A; Araujo, E P

    2013-11-01

    Autophagy is a highly regulated process that has an important role in the control of a wide range of cellular functions, such as organelle recycling, nutrient availability and tissue differentiation. A recent study has shown an increased autophagic activity in the adipose tissue of obese subjects, and a role for autophagy in obesity-associated insulin resistance was proposed. Body mass reduction is the most efficient approach to tackle insulin resistance in over-weight subjects; however, the impact of weight loss in adipose tissue autophagy is unknown. Adipose tissue autophagy was evaluated in mice and humans. First, a mouse model of diet-induced obesity and diabetes was maintained on a 15-day, 40% caloric restriction. At baseline, markers of autophagy were increased in obese mice as compared with lean controls. Upon caloric restriction, autophagy increased in the lean mice, whereas it decreased in the obese mice. The reintroduction of ad libitum feeding was sufficient to rapidly reduce autophagy in the lean mice and increase autophagy in the obese mice. In the second part of the study, autophagy was evaluated in the subcutaneous adipose tissue of nine obese-non-diabetic and six obese-diabetic subjects undergoing bariatric surgery for body mass reduction. Specimens were collected during the surgery and approximately 1 year later. Markers of systemic inflammation, such as tumor necrosis factor-1α, interleukin (IL)-6 and IL-1β were evaluated. As in the mouse model, human obesity was associated with increased autophagy, and body mass reduction led to an attenuation of autophagy in the adipose tissue. Obesity and caloric overfeeding are associated with the defective regulation of autophagy in the adipose tissue. The studies in obese-diabetic subjects undergoing improved metabolic control following calorie restriction suggest that autophagy and inflammation are regulated independently.

  11. Improved repair of bone defects with prevascularized tissue-engineered bones constructed in a perfusion bioreactor.

    Science.gov (United States)

    Li, De-Qiang; Li, Ming; Liu, Pei-Lai; Zhang, Yuan-Kai; Lu, Jian-Xi; Li, Jian-Min

    2014-10-01

    Vascularization of tissue-engineered bones is critical to achieving satisfactory repair of bone defects. The authors investigated the use of prevascularized tissue-engineered bone for repairing bone defects. The new bone was greater in the prevascularized group than in the non-vascularized group, indicating that prevascularized tissue-engineered bone improves the repair of bone defects. [Orthopedics. 2014; 37(10):685-690.]. Copyright 2014, SLACK Incorporated.

  12. Soft Tissue Reconstruction of Complete Circumferential Defects of the Upper Extremity

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    Zhi Yang Ng

    2017-03-01

    Full Text Available BackgroundUpper extremity soft tissue defects with complete circumferential involvement are not common. Coupled with the unique anatomy of the upper extremity, the underlying etiology of such circumferential soft tissue defects represent additional reconstructive challenges that require treatment to be tailored to both the patient and the wound. The aim of this study is to review the various options for soft tissue reconstruction of complete circumferential defects in the upper extremity.MethodsA literature review of PubMed and MEDLINE up to December 2016 was performed. The current study focuses on forearm and arm defects from the level at or proximal to the wrist and were assessed based on Tajima's classification (J Trauma 1974. Data reviewed for analysis included patient demographics, causality, defect size, reconstructive technique(s employed, and postoperative follow-up and functional outcomes (when available.ResultsIn accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, 14 unique articles were identified for a total of 50 patients (mean=28.1 years. Underlying etiologies varied from extensive thermal or electrical burns to high impact trauma leading to degloving or avulsion, crush injuries, or even occur iatrogenically after tumor extirpation or extensive debridement. Treatment options ranged from the application of negative pressure wound dressings to the opposite end of the spectrum in hand transplantation.ConclusionsWith the evolution of reconstructive techniques over time, the extent of functional and aesthetic rehabilitation of these complex upper extremity injuries has also improved. The proposed management algorithm comprehensively addresses the inherent challenges associated with these complex cases.

  13. Radiographic outcomes following treatment of intrabony defect with guided tissue regeneration in aggressive periodontitis.

    Science.gov (United States)

    Rakmanee, Thanasak; Griffiths, Gareth S; Auplish, Gita; Darbar, Ulpee; Petrie, Aviva; Olsen, Irwin; Donos, Nikolaos

    2016-07-01

    This study reports the radiographic analysis of a split-mouth, single-blinded, randomised controlled clinical trial which was designed to compare the efficacy of simplified papilla preservation flap (SPPF) with or without guided tissue regeneration (GTR) in patients with aggressive periodontitis (AgP). Eighteen AgP patients who had similar bilateral intrabony defects were treated. In all patients, the defects presented with radiographic evidence of an intrabony defect ≥3 and ≥5 mm of periodontal pocket depths (PPD). The surgical procedures included access for root instrumentation using SPPF alone (control) or, after debridement, a placement of resorbable GTR membrane (test). The standardised radiographic assessments were carried out at pre-surgical baseline and at 6 and 12 month post-surgery. Radiographic linear measurements and subtraction radiography were used as the method of analysis. Both treatments showed significant improvements in linear radiographic bone fill and defect resolution at 6 and 12 months, compared to baseline. The 12-month subtraction radiography at the GTR sites showed a significant improvement compared to the 6-month outcomes. Both therapies were effective in the treatment of intrabony defects in AgP patients although no significant differences between them could be demonstrated. The finding that the bone fill and resolution of the defect at the GTR sites were significantly higher at 12 months than at 6 months after treatment indicates that bone regeneration is still an ongoing process at 6 months post-surgery. Radiographic assessment of periodontal regeneration should be carried out at 12 months post-surgery in order to evaluate the complete healing of the bony defect.

  14. Effectiveness of the Gastrocsoleous Flap for Coverage of Soft Tissue Defects in Leg with Emphasis on the Distal Third

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    Ali Karbalaeikhani

    2015-07-01

    Full Text Available Background: The standard methods for reconstruction of soft tissue defects in the leg include gastrocnemius flap for proximal third defects, soleus flap for middle third and free flap in the distal third. However, there are problems with the use of free flap, like increased operative time, damage of major vessels and the need for experienced microsurgeon. Mathods: This prospective study was undertaken on 23 patients (20 male and 3 female with the mean age 32.13 years (14 to 65. This group consisted of all of the patients referred to Dr Bahonar Hospital, Kerman with soft tissue defects between April 2011 and April 20012 and would give informed consent for participation in the study and treatment of the defect with muscle flaps. 8 patients with proximal third defects were treated with were treated with gastrocnemius flap, 4 with middle third defects with soleus flap and 3 with reverse soleus flap and 8 with distal third defects with reverse soleus flap. The patients were followed up for at least 1 year. Finally the results were analyzed by SPSS 16. Results: In patients with soft tissue defect in proximal and middle third of leg repair was successful in all. In 5 patients with soft tissue defect in distal third of leg repair was complete but in 3 of them flap failure was seen. Overall success rate for reverse soleous flap was 72.7%. Conclusion: The success rate of the flap for the upper and lower thirds was similar to other studies and seems that this is the standard method. In the distal third defects the reverse soleous flap failed in 3 cases and it seems that preoperative investigations such as angiography must be performed before embarking on such a procedure.

  15. [Clinical observation of microsurgial repairing for the treatment of soft tissue defection of heel].

    Science.gov (United States)

    Liu, Jing-sheng; Wang, Yu-liang; Xia, Ya-yi; Hao, Jun-long; Zhou, Hai-yu; Zhao, Lin; Wu, Meng; Wang, Xu

    2014-10-01

    T o summarize the clinical effects of the repairing methods for skin and soft tissue defection of heel. From June 1998 to June 2009,42 patients with skin and soft tissue defection of heel underwent the repairing treatment,including 23 males and 19 females, with an average age of 37 years old ranging from 18 to 65. The causes of injuries included mangled injury in 22 cases, high fall injury in 10 cases, cut injury in 5 cases,melanoma in 3 cases, decubital ulcer in 2 cases. Of the 42 cases, 27 were on left side and 15 on right side. The defect area of skin ranged from 3 cm x 2 cm to 18 cm x 16 cm. The time between the injury and surgery ranged from 8 hours to 10 years. The wounds were repaired separately by medial plantar flap in 13 cases, lesser saphenous sural nerve vascular island flap in 18 cases, saphenous neurocutaneous vascular flap in 11 cases. The patients' outcome were evaluated with appearance,blood supply, texture, resilience and two points discrimination of the flaps. All of the 42 flaps were survived. The distal skin necrosis occurred in 2 flaps, but healing occurred after debridement and intermediate thickness skin grafting. Three patients with sinus formation healed after 5 to 12 months of dressing change. All patients were follow-up for 8 months to 6 years. The flaps of all patients gained a satisfied shape after operation. The patients had a normal gait, the flaps had a good sense and a resistance to wearing,and no ulcer occurred. The two point discrimination of the flap was 4 to 12 mm. It is convenient and effective to repair the heel skin and soft tissue defects using medial plantar island skin flap when the defects is less then 8 cmx6 cm. As reliable blood supply,major artery preservation and high survival, the lesser saphenous sural nerve vascular island flap and saphenous neurocutaneous vascular flap can be transferred to repair the large soft tissue defect of heel.

  16. The method of diagnosis and classification of the gingival line defects of the teeth hard tissues

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    Olena Bulbuk

    2017-06-01

    Full Text Available For solving the problem of diagnosis and treatment of hard tissue defects the significant role belongs to the choice of tactics for dental treatment of hard tissue defects located in the gingival line of any tooth. This work aims to study the problems of diagnosis and classification of gingival line defects of the teeth hard tissues. That will contribute to the objectification of differentiated diagnostic and therapeutic approaches in the dental treatment of various clinical variants of these defects localization. The objective of the study – is to develop the anatomical-functional classification for differentiated estimation of hard tissue defects in the gingival part, as the basis for the application of differential diagnostic-therapeutic approaches to the dental treatment of hard tissue defects disposed in the gingival part of any tooth. Materials and methods of investigation: There was conducted the examination of 48 patients with hard tissue defects located in the gingival part of any tooth. To assess the magnitude of gingival line destruction the periodontal probe and X-ray examination were used. Results. The result of the performed research the classification of the gingival line defects of the hard tissues was offered using exponent power. The value of this indicator is equal to an integer number expressed in millimeters of distance from the epithelial attachment to the cavity’s bottom of defect. Conclusions. The proposed classification fills an obvious gap in academic representations about hard tissue defects located in the gingival part of any tooth. Also it offers the prospects of consensus on differentiated diagnostic-therapeutic approaches in different clinical variants of location.  This classification builds methodological “bridge of continuity” between therapeutic and prosthetic dentistry in the field of treatment of the gingival line defects of dental hard tissues.

  17. Microvascular free flaps in the management of war wounds with tissue defects

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    Kozarski Jefta

    2003-01-01

    Full Text Available Background. War wounds caused by modern infantry weapons or explosive devices are very often associated with the defects of soft and bone tissue. According to their structure, tissue defects can be simple or complex. In accordance with war surgical doctrine, at the Clinic for Plastic Surgery and Burns of the Military Medical Academy, free flaps were used in the treatment of 108 patients with large tissue defects. With the aim of closing war wounds, covering deep structures, or making the preconditions for reconstruction of deep structures, free flaps were applied in primary, delayed, or secondary term. The main criteria for using free flaps were general condition of the wounded, extent, location, and structure of tissue defects. The aim was also to point out the advantages and disadvantages of the application of free flaps in the treatment of war wounds. Methods. One hundred and eleven microvascular free flaps were applied, both simple and complex, for closing the war wounds with extensive tissue defects. The main criteria for the application of free flaps were: general condition of the wounded, size, localization, and structure of tissue defects. For the extensive defects of the tissue, as well as for severely contaminated wounds latissimus dorsi free flaps were used. For tissue defects of distal parts of the lower extremities, scapular free flaps were preferred. While using free tissue transfer for recompensation of bone defects, free vascularized fibular grafts were applied, and in skin and bone defects complex free osteoseptocutaneous fibular, free osteoseptocutaneous radial forearm, and free skin-bone scapular flaps were used. Results. After free flap transfer 16 (14,4% revisions were performed, and after 8 unsuccessful revisions another free flaps were utilized in 3 (37,5% patients, and cross leg flaps in 5 (62,5% patients. Conclusion. The treatment of war wounds with large tissue defects by the application of free microvascular flaps

  18. Analysis of electronic models for solar cells including energy resolved defect densities

    Energy Technology Data Exchange (ETDEWEB)

    Glitzky, Annegret

    2010-07-01

    We introduce an electronic model for solar cells including energy resolved defect densities. The resulting drift-diffusion model corresponds to a generalized van Roosbroeck system with additional source terms coupled with ODEs containing space and energy as parameters for all defect densities. The system has to be considered in heterostructures and with mixed boundary conditions from device simulation. We give a weak formulation of the problem. If the boundary data and the sources are compatible with thermodynamic equilibrium the free energy along solutions decays monotonously. In other cases it may be increasing, but we estimate its growth. We establish boundedness and uniqueness results and prove the existence of a weak solution. This is done by considering a regularized problem, showing its solvability and the boundedness of its solutions independent of the regularization level. (orig.)

  19. Tissue- and cell-specific mitochondrial defect in Parkin-deficient mice.

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    Maria Damiano

    Full Text Available Loss of Parkin, encoded by PARK2 gene, is a major cause of autosomal recessive Parkinson's disease. In Drosophila and mammalian cell models Parkin has been shown in to play a role in various processes essential to maintenance of mitochondrial quality, including mitochondrial dynamics, biogenesis and degradation. However, the relevance of altered mitochondrial quality control mechanisms to neuronal survival in vivo is still under debate. We addressed this issue in the brain of PARK2-/- mice using an integrated mitochondrial evaluation, including analysis of respiration by polarography or by fluorescence, respiratory complexes activity by spectrophotometric assays, mitochondrial membrane potential by rhodamine 123 fluorescence, mitochondrial DNA content by real time PCR, and oxidative stress by total glutathione measurement, proteasome activity, SOD2 expression and proteins oxidative damage. Respiration rates were lowered in PARK2-/- brain with high resolution but not standard respirometry. This defect was specific to the striatum, where it was prominent in neurons but less severe in astrocytes. It was present in primary embryonic cells and did not worsen in vivo from 9 to 24 months of age. It was not associated with any respiratory complex defect, including complex I. Mitochondrial inner membrane potential in PARK2-/- mice was similar to that of wild-type mice but showed increased sensitivity to uncoupling with ageing in striatum. The presence of oxidative stress was suggested in the striatum by increased mitochondrial glutathione content and oxidative adducts but normal proteasome activity showed efficient compensation. SOD2 expression was increased only in the striatum of PARK2-/- mice at 24 months of age. Altogether our results show a tissue-specific mitochondrial defect, present early in life of PARK2-/- mice, mildly affecting respiration, without prominent impact on mitochondrial membrane potential, whose underlying mechanisms remain to be

  20. Hydrogel derived from porcine decellularized nerve tissue as a promising biomaterial for repairing peripheral nerve defects.

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    Lin, Tao; Liu, Sheng; Chen, Shihao; Qiu, Shuai; Rao, Zilong; Liu, Jianghui; Zhu, Shuang; Yan, Liwei; Mao, Haiquan; Zhu, Qingtang; Quan, Daping; Liu, Xiaolin

    2018-04-09

    Decellularized matrix hydrogels derived from tissues or organs have been used for tissue repair due to their biocompatibility, tunability, and tissue-specific extracellular matrix (ECM) components. However, the preparation of decellularized peripheral nerve matrix hydrogels and their use to repair nerve defects have not been reported. Here, we developed a hydrogel from porcine decellularized nerve matrix (pDNM-G), which was confirmed to have minimal DNA content and retain collagen and glycosaminoglycans content, thereby allowing gelatinization. The pDNM-G exhibited a nanofibrous structure similar to that of natural ECM, and a ∼280-Pa storage modulus at 10 mg/mL similar to that of native neural tissues. Western blot and liquid chromatography tandem mass spectrometry analysis revealed that the pDNM-G consisted mostly of ECM proteins and contained primary ECM-related proteins, including fibronectin and collagen I and IV). In vitro experiments showed that pDNM-G supported Schwann cell proliferation and preserved cell morphology. Additionally, in a 15-mm rat sciatic nerve defect model, pDNM-G was combined with electrospun poly(lactic-acid)-co-poly(trimethylene-carbonate)conduits to bridge the defect, which did not elicit an adverse immune response and promoted the activation of M2 macrophages associated with a constructive remodeling response. Morphological analyses and electrophysiological and functional examinations revealed that the regenerative outcomes achieved by pDNM-G were superior to those by empty conduits and closed to those using rat decellularized nerve matrix allograft scaffolds. These findings indicated that pDNM-G, with its preserved ECM composition and nanofibrous structure, represents a promising biomaterial for peripheral nerve regeneration. Decellularized nerve allografts have been widely used to treat peripheral nerve injury. However, given their limited availability and lack of bioactive factors, efforts have been made to improve the efficacy

  1. Biodegradable hybrid tissue engineering scaffolds for reconstruction of large bone defects

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    Barati, Danial

    Complex skeletal injuries and large bone fractures are still a significant clinical problem in US. Approximately 1.5 million Americans (veterans, their families, and civilians) every year suffer from bone loss due to traumatic skeletal injuries, infection, and resection of primary tumors that require extensive grafting to bridge the gap. The US bone graft market is over $2.2 billion a year. Due to insufficient mechanical stability, lack of vascularity, and inadequate resorption of the graft, patients with traumatic large skeletal injuries undergo multiple costly operations followed by extensive recovery steps to maintain proper bone alignment and length. Current strategies for repairing damaged or diseased bones include autologous or allograft bone transplantations. However, limited availability of autografts and risk of disease transmission associated with allografts have necessitated the search for the development of new bone graft options and strategies. The overall goal of this project is to develop a much-needed bone-mimetic engineered graft as a substitute for current strategies providing required bone grafts for reconstruction of large bone defects. This project will use the structure of natural cortical bone as a guide to produce an engineered bone graft with balanced strength, osteogenesis, vascularization, and resorption. The outcome of this project will be a biodegradable hybrid scaffold system (similar to natural cortical bone) including a mechanically strong scaffold allowing for mechanical stability of the load-bearing defect site and a soft and highly porous structure such as a hydrogel phase which will allow for efficient cell and growth factor delivery into the defect implantation site, cell niche establishment and promotion of mineralization. Successful completion of this project will transform bone graft technology for regeneration of complex bone defects from a frozen or freeze-dried allograft to a safe, infection-free, mechanically

  2. Angiogenic peptide nanofibers repair cardiac tissue defect after myocardial infarction.

    Science.gov (United States)

    Rufaihah, Abdul Jalil; Yasa, I Ceren; Ramanujam, Vaibavi Srirangam; Arularasu, Suganya Cheyyatraivendran; Kofidis, Theo; Guler, Mustafa O; Tekinay, Ayse B

    2017-08-01

    Myocardial infarction remains one of the top leading causes of death in the world and the damage sustained in the heart eventually develops into heart failure. Limited conventional treatment options due to the inability of the myocardium to regenerate after injury and shortage of organ donors require the development of alternative therapies to repair the damaged myocardium. Current efforts in repairing damage after myocardial infarction concentrates on using biologically derived molecules such as growth factors or stem cells, which carry risks of serious side effects including the formation of teratomas. Here, we demonstrate that synthetic glycosaminoglycan (GAG) mimetic peptide nanofiber scaffolds induce neovascularization in cardiovascular tissue after myocardial infarction, without the addition of any biologically derived factors or stem cells. When the GAG mimetic nanofiber gels were injected in the infarct site of rodent myocardial infarct model, increased VEGF-A expression and recruitment of vascular cells was observed. This was accompanied with significant degree of neovascularization and better cardiac performance when compared to the control saline group. The results demonstrate the potential of future clinical applications of these bioactive peptide nanofibers as a promising strategy for cardiovascular repair. We present a synthetic bioactive peptide nanofiber system can enhance cardiac function and enhance cardiovascular regeneration after myocardial infarction (MI) without the addition of growth factors, stem cells or other biologically derived molecules. Current state of the art in cardiac repair after MI utilize at least one of the above mentioned biologically derived molecules, thus our approach is ground-breaking for cardiovascular therapy after MI. In this work, we showed that synthetic glycosaminoglycan (GAG) mimetic peptide nanofiber scaffolds induce neovascularization and cardiomyocyte differentiation for the regeneration of cardiovascular

  3. Biomedical Technologies in the Treatment of Skin and Soft Tissue Defects in Patients with Diabetic Foot Syndrome

    Directory of Open Access Journals (Sweden)

    Magomed D Dibirov

    2016-03-01

    Full Text Available The aim of our study was to investigate the effectiveness of collagen implants in the closure of tissue defects. We offer a method that enables us to avoid the drawbacks of autodermoplasty based on the free split-thickness skin graft. Materials and Methods: This paper describes all steps of treatment of skin and soft tissue defects in patients with diabetic foot syndrome (DFS, including ultrasonic cavitation (UC with hydrosurgical debridement (HD to remove necrotic debris, purulent pellicle and bacterial biofilm, and an alternative technique for wound defect closure using high-tech biomaterials based on type I collagen (“Collost”, “Salvecoll”. Results: Use of type I collagen (“Collost”, “Salvecoll” as a component of combination treatment of tissue defects in DFS allowed us to increase the relative rate of wound healing, reduce the incidence of high-level amputations, and significantly reduce inpatient surgical coverage around the clock and speed up a patient's transfer to outpatient care. Conclusion: Ultrasonic cavitation with hydrosurgical debridement is the most effective procedure for wound preparation for closure. The use of bioplastic collagen materials in patients with DFS is the most effective solution in the management of wound defects.

  4. Omental free-tissue transfer for coverage of complex upper extremity and hand defects--the forgotten flap.

    Science.gov (United States)

    Seitz, Iris A; Williams, Craig S; Wiedrich, Thomas A; Henry, Ginard; Seiler, John G; Schechter, Loren S

    2009-12-01

    Free omental tissue transfer is a versatile reconstructive option for trunk, head and neck, and extremity reconstruction. Its utility is due to the length and caliber of the vascular pedicle and the malleability and surface area of the flap. We report our experience with omental free flap coverage of complex upper-extremity defects. A retrospective analysis of eight omental free-tissue transfers in seven patients with complex upper-extremity defects between 1999 and 2008 was performed. Indications, operative technique, and outcome were evaluated. Patient age ranged from 12 to 59 years with five male and two female patients. Indications included tissue defects due to crush-degloving injuries, pitbull mauling, or necrotizing soft tissue infection. All patients had prior operations including: revascularization, debridement, tendon repair, skin grafts, and/or fixation of associated fractures. One patient sustained severe bilateral crush-degloving injuries requiring free omental hemiflap coverage of both hands. The mean defect size was 291 cm(2) with all patients achieving complete wound coverage. No flap loss or major complications were noted. Laparoscopic-assisted omental free flap harvest was performed in conjunction with the general surgery team in three cases. Mean follow-up was 2 years. The omental free flap is a valuable, often overlooked reconstructive option. The long vascular pedicle and large amount of pliable, well-vascularized tissue allow the flap to be aggressively contoured to meet the needs of complex three-dimensional defects. In addition, laparoscopic-assisted harvest may aid with flap dissection and may result in reduced donor-site morbidity.

  5. Efficacy of Connective Tissue with and without Periosteum in Regeneration of Intrabony Defects

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    Vahid Esfahanian

    2014-12-01

    Full Text Available Background and aims. Connective tissue grafts with and without periosteum is used in regenerative treatments of bone and has demonstrated successful outcomes in previous investigations. The aim of present study was to evaluate the effec-tiveness of connective tissue graft with and without periosteum in regeneration of intrabony defects. Materials and methods. In this single-blind randomized split-mouth clinical trial, 15 pairs of intrabony defects in 15 pa-tients with moderate to advanced periodontitis were treated by periosteal connective tissue graft + ABBM (test group or non-periosteal connective tissue graft + ABBM (control group. Probing pocket depth, clinical attachment level, free gingi-val margin position, bone crestal position, crest defect depth and defect depth to stent were measured at baseline and after six months by surgical re-entry. Data was analyzed by Student’s t-test and paired t-tests (α=0.05. Results. Changes in clinical parameters after 6 months in the test and control groups were as follows: mean of PPD reduc-tion: 3.1±0.6 (P<0.0001; 2.5±1.0 mm (P<0.0001, CAL gain: 2.3±0.9 (P<0.0001; 2.2±1.0 mm (P<0.0001, bone fill: 2.2±0.7 mm (P<0.0001; 2.2±0.7 mm (P<0.0001, respectively. No significant differences in the position of free gingival margin were observed during 6 months compared to baseline in both groups. Conclusion. Combinations of periosteal connective tissue graft + ABBM and non-periosteal connective tissue graft + ABBM were similarly effective in treating intrabony defects without any favor for any group. Connective tissue and perio-steum can be equally effective in regeneration of intrabony defects.

  6. The composite anterolateral thigh flap for achilles tendon and soft tissue defect reconstruction with tendon repair by fascia with double or triple folding technique.

    Science.gov (United States)

    Youn, Seung Ki; Kim, Sang Wha; Kim, Youn Hwan; Hwang, Kyu Tae

    2015-11-01

    Rupture of the Achilles tendon is usually managed by surgical intervention. Recurrent tendon ruptures, segmental tendon defects, and overlying soft tissue defects render reconstructive procedures challenging. In this report, we present double or triple folding technique of the anterolateral thigh (ALT) free flap, and report the clinical outcomes of the reconstruction of combined defects, including the Achilles tendon and overlying soft tissue. From 2008 to 2013, 7 patients underwent reconstruction of combined Achilles tendon and soft tissue defects. The sizes of the soft tissue defects ranged from 9 × 5 to 12 × 5 cm(2) . Combined defects were reconstructed with ALT free flap including the vastus lateralis fascia and rectus femoris fascia, using a double or triple folding technique. The ALT free flap covered the soft tissue defect and the fascia was folded two or three times into a tendon-like structure. Three patients had full-layer defects of the Achilles tendon, and four patients had partial defects over half the layer. The dimension of the skin paddle of the ALT flap was 12 × 6 to 16 × 8 cm(2), and the dimension of the fascia was 12 × 8 to 16 × 10 cm(2). All the donor sites were closed primarily. All the flaps survived completely without complication. The mean follow-up period was 14.9 months. All patients were able to stand and ambulate. The double or triple folding technique of the ALT free flap represents simple, economical use of tissue, with minimal donor site morbidity. Thus, this technique may be useful and versatile reconstructive option for combined defects. © 2015 Wiley Periodicals, Inc.

  7. Bone tissue ultrastructural defects in a mouse model for osteogenesis imperfecta: a Raman spectroscopy study

    Science.gov (United States)

    Chen, Tsoching; Kozloff, Kenneth M.; Goldstein, Steven A.; Morris, Michael D.

    2004-07-01

    Osteogenesis imperfecta (OI) is genetic defect in which the genes that code for the α1(I) or α2(I) chains of type I collagen are defective. The defects often result in substitution of a bulky amino acid for glycine, causing formation of collagen that can not form the normal triple helix. Depending on the details of the defects, the outcomes range from controllable to lethal. This study focuses on OI type IV, a more common and moderately severe form of the disease. People with the disease have a substantial increase in the risk and rate of fracture. We examine the spectroscopic consequences of these defects, using a mouse model (BRTL) that mimics OI type IV. We compare Raman images from tibial cortical tissue of wild-type mice and BRTL mice with single copy of mutation and show that both mineral to matrix ratios and collagen inter-fibril cross-links are different in wild-type and mutant mice.

  8. Defective Wound-healing in Aging Gingival Tissue.

    Science.gov (United States)

    Cáceres, M; Oyarzun, A; Smith, P C

    2014-07-01

    Aging may negatively affect gingival wound-healing. However, little is known about the mechanisms underlying this phenomenon. The present study examined the cellular responses associated with gingival wound-healing in aging. Primary cultures of human gingival fibroblasts were obtained from healthy young and aged donors for the analysis of cell proliferation, cell invasion, myofibroblastic differentiation, and collagen gel remodeling. Serum from young and old rats was used to stimulate cell migration. Gingival repair was evaluated in Sprague-Dawley rats of different ages. Data were analyzed by the Mann-Whitney and Kruskal-Wallis tests, with a p value of .05. Fibroblasts from aged donors showed a significant decrease in cell proliferation, migration, Rac activation, and collagen remodeling when compared with young fibroblasts. Serum from young rats induced higher cell migration when compared with serum from old rats. After TGF-beta1 stimulation, both young and old fibroblasts demonstrated increased levels of alpha-SMA. However, alpha-SMA was incorporated into actin stress fibers in young but not in old fibroblasts. After 7 days of repair, a significant delay in gingival wound-healing was observed in old rats. The present study suggests that cell migration, myofibroblastic differentiation, collagen gel remodeling, and proliferation are decreased in aged fibroblasts. In addition, altered cell migration in wound-healing may be attributable not only to cellular defects but also to changes in serum factors associated with the senescence process. © International & American Associations for Dental Research.

  9. One-stage reconstruction of soft tissue defects with the sandwich technique: Collagen-elastin dermal template and skin grafts

    Directory of Open Access Journals (Sweden)

    Uwe Wollina

    2011-01-01

    Full Text Available Background : A full-thickness soft tissue defect closure often needs complex procedures. The use of dermal templates can be helpful in improving the outcome. Objective : The objective was to evaluate a sandwich technique combining the dermal collagen-elastin matrix with skin grafts in a one-stage procedure. Materials and Methods : Twenty-three patients with 27 wounds were enrolled in this prospective single-centre observational study. The mean age was 74.8 ± 17.2 years. Included were full-thickness defects with exposed bone, cartilage and/ or tendons. The dermal collagen-elastin matrix was applied onto the wound bed accomplished by skin transplants, i.e. ′sandwich′ transplantation. In six wounds, the transplants were treated with intermittent negative pressure therapy. Results : The size of defects was ≤875 cm 2 . The use of the dermal template resulted in a complete and stable granulation in 100% of wounds. Seventeen defects showed a complete closure and 19 achieved a complete granulation with an incomplete closure. There was a marked pain relief. No adverse events were noted due to the dermal template usage. Conclusions : Sandwich transplantation with the collagen-elastin matrix is a useful tool when dealing with full-thickness soft tissue defects with exposed bone, cartilage or tendons.

  10. The use of nanocrystalline silver for the treatment of massive soft tissue defects with exposed bone.

    Science.gov (United States)

    Jenwitheesuk, Kamonwan; Surakunprapha, Palakorn; Chowchuen, Bowornsilp

    2013-09-01

    In a complex wound with exposed tendon, joint or bone caused by trauma, soft tissue reconstruction is required to obtain function and aesthetic coverage. Surgical reconstruction can be performed using a variety of different techniques. The authors report their experience using a nanocrystalline silver with or without vacuum assisted wound closure to salvage the exposed vital structures such as bone, joint or tendon in traumatic wounds. The present study included 12 patients with 15 wounds that exposed vital structures especially in the lower extremities. After adequate debridement, four wounds were treated with nanocrystalline silver dressing and vacuum assisted wound closure, and ten wounds were treated in an out-patient program using nanocrystalline silver dressing. A preliminary evidence of impressive result was achieved with subsided infection and complete bony coverage by granulation tissue after treatment. Subsequently, a secondary healing or a split thickness skin graft was applied. The authors present the satisfactory results of alternative techniques that may be used for the massive soft tissue defects with exposed bone.

  11. SIS with tissue-cultured allogenic cartilages patch tracheoplasty in a rabbit model for tracheal defect.

    Science.gov (United States)

    Zhang, Longfang; Liu, Zhi; Cui, Pengcheng; Zhao, Daqing; Chen, Wenxian

    2007-06-01

    In the rabbit model, small intestinal submucosa (SIS) compounded with tissue-cultured allogenic cartilages appeared to be an efficacious method for the patch repair of partial circumferential tracheal defects instead of autologous grafts. SIS appears to be a safe and promising means of facilitating neovascularization and tissue regeneration. The long-term use of SIS and tissue-cultured allogenic cartilages warrants further investigation. Tracheal defect reparation remains a challenging surgical problem that can require reconstruction using autologous grafts or artificial stents. This study was performed to evaluate the efficacy of SIS, a biocompatible, acellular matrix, compounded with different tissue-cultured allogenic cartilages, in the repair of a critical-size tracheal defect. A full-thickness defect (4 x 8 mm) was created in tracheal rings four to six in adult rabbits. A piece of 8-ply SIS sandwiched in thyroid cartilage, auricular cartilage, or without cartilage, respectively (designated experiment 1, 2, or 3, respectively), was sutured to the edges of the defect with interrupted 4-0 polypropylene sutures. In control animals, the defect was closed with lamina praetrachealis. All animals were followed until signs of dyspnea became apparent or for 4 or 12 weeks. After follow-up and euthanasia, the trachea was harvested and prepared for histologic evaluation using conventional techniques. All animals tolerated the procedure well but two animals in group 1 (n=5), three in group 2 (n=5), and one in group 3 (n=5) had stridor after operation and expired within 1 month. Histologically, neovascularization of the patch was noted with moderate inflammation. The surface of the SIS patch was covered with a lining of ciliated epithelial cells. The tissue-cultured allogenic cartilages degraded to some extent.

  12. Enamel matrix derivative (Emdogain) for periodontal tissue regeneration in intrabony defects.

    Science.gov (United States)

    Esposito, M; Coulthard, P; Worthington, H V

    2003-01-01

    Periodontitis is a chronic infective disease of the gums caused by bacteria present in dental plaque. This condition induces the breakdown of the tooth supporting apparatus until teeth are lost. Surgery may be indicated to arrest disease progression and regenerate lost tissues. Several surgical techniques have been developed to regenerate periodontal tissues including guided tissue regeneration (GTR), bone grafting (BG) and the use of enamel matrix derivative (EMD). EMD is an extract of enamel matrix and contains amelogenins of various molecular weights. There is evidence to show that amelogenins are involved not only in enamel formation, but also in the formation of the periodontal attachment during tooth formation. To test the efficacy of EMD in comparison with open flap debridement, GTR and various BG procedures for the treatment of intrabony defects. We searched the Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. Several journals were handsearched. No language restrictions were applied. Authors of randomised controlled trials (RCTs) identified, personal contacts and the manufacturer were contacted to identify unpublished trials. Most recent search: January 2003. RCTs on patients affected by periodontitis having intrabony defects treated with EMD compared with open flap debridement, GTR and various BG procedures with at least one year follow up. The outcome measures considered were: tooth loss, changes in probing attachment levels (PAL), pocket depths (PPD), gingival recessions (REC), marginal bone levels on intraoral radiographs and postoperative infections. Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two reviewers. Results were expressed as random effect models using weighted mean differences for continuous outcomes and relative risk for dichotomous outcomes with 95

  13. Thoracodorsal artery perforator fasciocutaneous flap: A versatile alternative for coverage of various soft tissue defects

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    Celalettin Sever

    2012-01-01

    Full Text Available Objective: The thoracodorsal artery perforator (TDAP flap has contributed to the efficient reconstruction of tissue defects that require a large amount of cutaneous tissue. The optimal reconstruction method should provide thin, and well-vascularized tissue with minimal donor-site morbidity. The indications for the use of this particular flap with other flaps are discussed in this article. Materials and Methods: Thirteen patients underwent soft tissue reconstruction using TDAP flaps between 2009 and 2011. Of those, there were four cases of antecubital burn contracture, three cases of axillary burn contracture, two cases of giant hair cell nevus of upper extremity, two cases of axillary reconstruction following severe recurrent hidradenitis, and two cases of crush injury. All patients were male and their ages ranged from 20 to 23 (average, 21 years. The mean follow-up period was 8 months (range, 4-22 months. Results: All reconstructive procedures were completed without any major complications. Minor complications related to transfered flaps were wound dehiscence in one case, transient venous congestion in two cases. Minor complication related to the donor site was seroma in one case. The success rate was 100%, with satisfactory cosmetic results. Conclusions: The TDAP flap is a safe and extremely versatile flap that offers significant advantages in acute and delayed reconstruction. Although the vascular anatomy may be variable, free and pedicled TDAP flap is a versatile alternative for soft tissue defects. It adapts very well to the soft tissue defects with acceptable donor site scar.

  14. Methylation Profiling Defines an Extensive Field Defect in Histologically Normal Prostate Tissues Associated with Prostate Cancer

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    Bing Yang

    2013-04-01

    Full Text Available Prostate cancer (PCa is typically found as a multifocal disease suggesting the potential for molecular defects within the morphologically normal tissue. The frequency and spatial extent of DNA methylation changes encompassing a potential field defect are unknown. A comparison of non-tumor-associated (NTA prostate to histologically indistinguishable tumor-associated (TA prostate tissues detected a distinct profile of DNA methylation alterations (0.2% using genome-wide DNA arrays based on the Encyclopedia of DNA Elements 18 sequence that tile both gene-rich and poor regions. Hypomethylation (87% occurred more frequently than hypermethylation (13%. Several of the most significantly altered loci (CAV1, EVX1, MCF2L, and FGF1 were then used as probes to map the extent of these DNA methylation changes in normal tissues from prostates containing cancer. In TA tissues, the extent of methylation was similar both adjacent (2 mm and at a distance (>1 cm from tumor foci. These loci were also able to distinguish NTA from TA tissues in a validation set of patient samples. These mapping studies indicate that a spatially widespread epigenetic defect occurs in the peripheral prostate tissues of men who have PCa that may be useful in the detection of this disease.

  15. Adipose stem cells used to reconstruct 13 cases with cranio-maxillofacial hard-tissue defects.

    Science.gov (United States)

    Sándor, George K; Numminen, Jura; Wolff, Jan; Thesleff, Tuomo; Miettinen, Aimo; Tuovinen, Veikko J; Mannerström, Bettina; Patrikoski, Mimmi; Seppänen, Riitta; Miettinen, Susanna; Rautiainen, Markus; Öhman, Juha

    2014-04-01

    Although isolated reports of hard-tissue reconstruction in the cranio-maxillofacial skeleton exist, multipatient case series are lacking. This study aimed to review the experience with 13 consecutive cases of cranio-maxillofacial hard-tissue defects at four anatomically different sites, namely frontal sinus (3 cases), cranial bone (5 cases), mandible (3 cases), and nasal septum (2 cases). Autologous adipose tissue was harvested from the anterior abdominal wall, and adipose-derived stem cells were cultured, expanded, and then seeded onto resorbable scaffold materials for subsequent reimplantation into hard-tissue defects. The defects were reconstructed with either bioactive glass or β-tricalcium phosphate scaffolds seeded with adipose-derived stem cells (ASCs), and in some cases with the addition of recombinant human bone morphogenetic protein-2. Production and use of ASCs were done according to good manufacturing practice guidelines. Follow-up time ranged from 12 to 52 months. Successful integration of the construct to the surrounding skeleton was noted in 10 of the 13 cases. Two cranial defect cases in which nonrigid resorbable containment meshes were used sustained bone resorption to the point that they required the procedure to be redone. One septal perforation case failed outright at 1 year because of the postsurgical resumption of the patient's uncontrolled nasal picking habit.

  16. Biomimetic coatings for bone tissue engineering of critical-sized defects

    NARCIS (Netherlands)

    Liu, Y.; Wu, G.; de Groot, K.

    2010-01-01

    The repair of critical-sized bone defects is still challenging in the fields of implantology, maxillofacial surgery and orthopaedics. Current therapies such as autografts and allografts are associated with various limitations. Cytokine-based bone tissue engineering has been attracting increasing

  17. Treatment strategy for guided tissue regeneration in various class II furcation defect: Case series

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    Pushpendra Kumar Verma

    2013-01-01

    Full Text Available Periodontal regeneration is a main aspect in the treatment of teeth affected by periodontitis. Periodontal regeneration in furcation areas is quite challenging, especially when it is in interproximal region. There are several techniques used alone or in combination considered to achieve periodontal regeneration, including the bone grafts or substitutes, guided tissue regeneration (GTR, root surface modification, and biological mediators. Many factors may account for variability in response to regenerative therapy in class II furcation. This case series describes the management of class II furcation defect in a mesial interproximal region of a maxillary tooth and other with a buccal class II furcation of mandibular tooth, with the help of surgical intervention including the GTR membrane and bone graft materials. This combined treatment resulted in healthy periodontium with a radiographic evidence of alveolar bone gain in both cases. This case series demonstrates that proper diagnosis, followed by removal of etiological factors and utilizing the combined treatment modalities will restore health and function of the tooth with the severe attachment loss.

  18. [Anterolateral thigh and groin conjoined flap for emergent repair of ultra-long complex tissue defects in forearm and hand].

    Science.gov (United States)

    Wang, Maorong; Gu, Yunfeng; Chen, Fusheng; Li, Jun; Wang, Jiangning; Yin, Yefeng

    2013-08-01

    To evaluate the effectiveness of anterolateral thigh and groin conjoined flap in emergent repair of ultra-long complex tissue defects in forearm and hand. Between February 2009 and October 2011, 6 patients with complex tissue defect of dorsal forearm and hand were in adminsion. There were 5 male and 1 female with an average age of 38.5 years (range, 32-47 years). Injury reasons included machine injury in 5 cases and traffic accident injury in 1 case. Injury to admission time was from 3 to 16 hours (mean, 6 hours). All case were single limb injury, including right forearm and hand injury in 4 cases and left forearm and hand injury in 2 cases. The wound area was from 36 cm x 9 cm to 48 cm x 12 cm. The type of associated injury included elbow dislocation associated with open injury in 2 cases; fractures of the radial, ulnar, and metacarpal bone in 4 cases; defects of wrist dorsal skin and extensor tendons of fingers and wrist in 5 cases; and defects of ulnar artery and ulnar nerve in 1 case. The anterolateral thigh and groin conjoined free flaps were used to repair defects in the forearm and hand in emergency. The area of flap was from 36 cm x 9 cm to 48 cm x 12 cm. Meanwhile the partial functional reconstruction was performed. The donor site was repaired by skin grafts. The anastomotic embolization of vascular pedicle and arteria interossea dorsalis occurred in 1 case, purulent secretion under the flap in 1 case, which were cured after symptomatic treatment; the skin flaps completely survived, and primary healing of the wounds were obtained in the other cases. The donor skin grafts survived in 2 cases, and partial necrosis of the skin graft of lower abdominal occurred in 4 cases, and healed after changing dressing. All of the 6 patients were followed up 3 to 18 months (mean, 10 months). The appearance and texture of the flaps were good. The protective sensation was recovered in 2 cases followed up for more than 14 months; no sensory recovery was observed in the other

  19. Autologous granulation tissue tubes for replacement of urethral defects: An experimental study in male rabbits.

    Science.gov (United States)

    Jiang, Shi-Wei; Xu, Zhong-Hua; Zhao, Yuan-Yuan; Yan, Lei; Zhou, Zun-Lin; Gu, Gang-Li

    2017-10-31

    Tubularized urethroplasty is commonly performed in clinical practice using genital skin flaps, bladder mucosa, and buccal mucosa. However, the long-term effects are not satisfying, and donor site morbidities remain a problem. Besides, those grafts are unavailable with malignant conditions of the urinary tract, a history of lichen sclerosis, or oral disease. An autologous granulation tissue tube of any required length and diameter can be produced by implanting foreign objects subcutaneously (Summary Fig.). The current study aimed to investigate to what extent of length this fully autologous tissue could be used for tubularized urethroplasty, satisfying urethral patency and tissue regeneration, in male rabbits. Twenty-seven New Zealand male rabbits were randomly divided into three groups. Silastic tubes were implanted subcutaneously in Group 1 and Group 2. By 2 weeks the granulation tissue encapsulating the tubes was harvested. In Group 1, pendulous urethral segments of 1 cm were excised, and urethroplasty was performed with the granulation tissue tube in an end-to-end fashion. In Group 2, a pendulous urethral segment of 1.5 cm was replaced with the tissue tube. In Group 3, a pendulous urethral defect of 1 cm was repaired by re-anastomosis as control. Serial urethrograms were performed at 1, 2 and 6 months postoperatively. Meanwhile, the neo-urethra were harvested and analyzed grossly and histologically. The urethrograms showed that all animals in Group 1 maintained a wide urethral caliber. In contrast, animals in Group 2 and Group 3 developed progressive strictures. Histologically, an intact urothelium with one to two cell layers lined the graft by 1 month, which was surrounded by increasing organized smooth muscle in Group 1. By 6 months, the grafts were completely integrated into native urethra. Nevertheless, extensive fibrosis occurred in Group 2 and Group 3. The tissue successfully maintained patency and guided urethral regeneration across a distance of 1

  20. Mineralization Induction of Gingival Fibroblasts and Construction of a Sandwich Tissue-Engineered Complex for Repairing Periodontal Defects.

    Science.gov (United States)

    Wu, Mingxuan; Wang, Jie; Zhang, Yanning; Liu, Huijuan; Dong, Fusheng

    2018-02-22

    BACKGROUND The ideal healing technique for periodontal tissue defects would involve the functional regeneration of the alveolar bone, cementum, and periodontal ligament, with new periodontal attachment formation. In this study, gingival fibroblasts were induced and a "sandwich" tissue-engineered complex (a tissue-engineered periodontal membrane between 2 tissue-engineered mineralized membranes) was constructed to repair periodontal defects. We evaluated the effects of gingival fibroblasts used as seed cells on the repair of periodontal defects and periodontal regeneration. MATERIAL AND METHODS Primitively cultured gingival fibroblasts were seeded bilaterally on Bio-Gide collagen membrane (a tissue-engineered periodontal membrane) or unilaterally on small intestinal submucosa segments, and their mineralization was induced. A tissue-engineered sandwich was constructed, comprising the tissue-engineered periodontal membrane flanked by 2 mineralized membranes. Periodontal defects in premolar regions of Beagles were repaired using the tissue-engineered sandwich or periodontal membranes. Periodontal reconstruction was compared to normal and trauma controls 10 or 20 days postoperatively. RESULTS Periodontal defects were completely repaired by the sandwich tissue-engineered complex, with intact new alveolar bone and cementum, and a new periodontal ligament, 10 days postoperatively. CONCLUSIONS The sandwich tissue-engineered complex can achieve ideal periodontal reconstruction rapidly.

  1. Mutation of p107 exacerbates the consequences of Rb loss in embryonic tissues and causes cardiac and blood vessel defects.

    Science.gov (United States)

    Berman, Seth D; West, Julie C; Danielian, Paul S; Caron, Alicia M; Stone, James R; Lees, Jacqueline A

    2009-09-01

    The retinoblastoma tumor-suppressor protein, pRb, is a member of the pocket protein family that includes p107 and p130. These proteins have well-defined roles in regulating entry into and exit from the cell cycle and also have cell cycle-independent roles in facilitating differentiation. Here we investigate the overlap between pocket protein's function during embryonic development by using conditional mutant alleles to generate Rb;p107 double-mutant embryos (DKOs) that develop in the absence of placental defects. These DKOs die between e13.5 and e14.5, much earlier than either the conditional Rb or the germline p107 single mutants, which survive to birth or are largely viable, respectively. Analyses of the e13.5 DKOs shows that p107 mutation exacerbates the phenotypes resulting from pRb loss in the central nervous system and lens, but not in the peripheral nervous system. In addition, these embryos exhibit novel phenotypes, including increased proliferation of blood vessel endothelial cells, and heart defects, including double-outlet right ventricle (DORV). The DORV is caused, at least in part, by a defect in blood vessel endothelial cells and/or heart mesenchymal cells. These findings demonstrate novel, overlapping functions for pRb and p107 in numerous murine tissues.

  2. The use of the ALT Flap and Lateral Femoral Cutaneous Nerve for the Reconstruction of Carpal Soft Tissue and Ulnar Nerve Defects: a Case Report.

    Science.gov (United States)

    Karonidis, Athanasios; Bouloumpasis, Serafeim; Apostolou, Konstantinos; Tsoutsos, Dimosthenis

    2015-06-01

    The anterolateral thigh (ALT) flap has become one of the workhorse flaps, with indications including diverse reconstructive problems. The lateral thigh area is also a useful donor site for nerve grafts. The lateral femoral cutaneous (LFC) nerve can be dissected along with the ALT flap for a substantial length, depending on the requirements of the recipient site. The LFC nerve can be used as a vascularized or non-vascularized nerve graft. The technique offers advantages and it can find clinical applications, satisfying the functional and aesthetic reconstructive requirements of a complex defect. We report the case of a patient who presented with traumatic soft tissue defect of the volar aspect of the wrist and ulnar nerve defect as a complication of a fracture of distal radius. An ALT flap was used to reconstruct the soft tissue defect. The ulnar nerve was resected due to necrosis and the gap was repaired with non-vascularized grafts of the anterior branch of the LFC nerve. The soft tissues were resurfaced successfully without complications. Functional recovery was good for the superficial branch of the ulnar nerve, whereas it was variable for the deep branch of the ulnar nerve. The anterolateral thigh area offers significant advantages as donor site in the reconstruction of complex soft tissue defects being a large source of vascularized skin, fat, fascia, muscle and nerve. This availability allows for single donor site dissection, minimizing the operating time and the associated morbidity.

  3. Engraftment of Prevascularized, Tissue Engineered Constructs in a Novel Rabbit Segmental Bone Defect Model

    Directory of Open Access Journals (Sweden)

    Alexandre Kaempfen

    2015-06-01

    Full Text Available The gold standard treatment of large segmental bone defects is autologous bone transfer, which suffers from low availability and additional morbidity. Tissue engineered bone able to engraft orthotopically and a suitable animal model for pre-clinical testing are direly needed. This study aimed to evaluate engraftment of tissue-engineered bone with different prevascularization strategies in a novel segmental defect model in the rabbit humerus. Decellularized bone matrix (Tutobone seeded with bone marrow mesenchymal stromal cells was used directly orthotopically or combined with a vessel and inserted immediately (1-step or only after six weeks of subcutaneous “incubation” (2-step. After 12 weeks, histological and radiological assessment was performed. Variable callus formation was observed. No bone formation or remodeling of the graft through TRAP positive osteoclasts could be detected. Instead, a variable amount of necrotic tissue formed. Although necrotic area correlated significantly with amount of vessels and the 2-step strategy had significantly more vessels than the 1-step strategy, no significant reduction of necrotic area was found. In conclusion, the animal model developed here represents a highly challenging situation, for which a suitable engineered bone graft with better prevascularization, better resorbability and higher osteogenicity has yet to be developed.

  4. Enamel matrix derivative (Emdogain) for periodontal tissue regeneration in intrabony defects. A Cochrane systematic review.

    Science.gov (United States)

    Esposito, Marco; Grusovin, Maria Gabriella; Papanikolaou, Nikolaos; Coulthard, Paul; Worthington, Helen V

    2009-01-01

    Periodontitis is a chronic infective disease of the gums caused by bacteria present in dental plaque. This condition induces the breakdown of the tooth supporting apparatus until teeth are lost. Surgery may be indicated to arrest disease progression and regenerate lost tissues. Several surgical techniques have been developed to regenerate periodontal tissues including guided tissue regeneration (GTR), bone grafting (BG) and the use of enamel matrix derivative (EMD). EMD is an extract of enamel matrix and contains amelogenins of various molecular weights. Amelogenins are involved in the formation of enamel and periodontal attachment formation during tooth development. To test whether EMD is effective, and to compare EMD versus GTR, and various BG procedures for the treatment of intrabony defects. The Cochrane Oral Health Group Trials Register, CENTRAL, MEDLINE and EMBASE were searched. Several dental journals were hand searched. No language restrictions were applied. Authors of randomised controlled trials (RCTs) identified, personal contacts and the manufacturer were contacted to identify unpublished trials. The last electronic search was conducted on 4 February 2009. RCTs on patients affected by periodontitis having intrabony defects of at least 3 mm treated with EMD compared with open flap debridement, GTR and various BG procedures with at least 1 year of follow-up. The outcome measures considered were: tooth loss, changes in probing attachment levels (PAL), pocket depths (PPD), gingival recessions (REC), bone levels from the bottom of the defects on intraoral radiographs, aesthetics and adverse events. The following time points were to be evaluated: 1, 5 and 10 years. Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by at least two authors. Results were expressed as random-effects models using mean differences for continuous outcomes and risk ratios (RR) for

  5. Imaging findings in patients with ventral dural defects and herniation of neural tissue

    International Nuclear Information System (INIS)

    Baur, A.; Staebler, A.; Reiser, M.; Psenner, K.; Hamburger, C.

    1997-01-01

    The aim of this paper is to describe clinical and imaging findings in three patients with ventral dural defects and herniation of the spinal cord or cauda equina. The literature is reviewed and the clinical, radiological and operative findings are compared. Three patients with ventral dural defects of different etiologies are presented. One patient gave a longstanding history of ankylosing spondylitis, the second patient presents 37 years after spinal trauma, and the third patient presents with spontaneous spinal cord herniation. All patients had typically slowly progressive neurological symptoms with multiple hospitalizations until diagnosis was made. Characteristic findings in postmyelographic CT included a ventral or ventrolateral displacement with deformation of the spinal cord or the cauda equina. Sagittal MRI showed this abrupt and localized anterior deviation of the spinal cord or the cauda equina to the posterior portions of a vertebral body with or without a bony vertebral defect optimally. Additionally, due to the ventral displacement of the spinal cord, the dorsal subarachnoid space was relatively enlarged without evidence of an arachnoid cyst, in all patients. Magnetic resonance imaging and postmyelographic CT can diagnose ventral dural defects with spinal cord herniation or nerve root entrapment. Dural defects must be considered in the presence of neurological symptoms in cases of longstanding ankylosing spondylitis, late sequelae of fractures of vertebral bodies, and without history of spinal trauma or surgery. (orig.). With 3 figs

  6. HdhQ111 Mice Exhibit Tissue Specific Metabolite Profiles that Include Striatal Lipid Accumulation.

    Directory of Open Access Journals (Sweden)

    Jeffrey B Carroll

    Full Text Available The HTT CAG expansion mutation causes Huntington's Disease and is associated with a wide range of cellular consequences, including altered metabolism. The mutant allele is expressed widely, in all tissues, but the striatum and cortex are especially vulnerable to its effects. To more fully understand this tissue-specificity, early in the disease process, we asked whether the metabolic impact of the mutant CAG expanded allele in heterozygous B6.HdhQ111/+ mice would be common across tissues, or whether tissues would have tissue-specific responses and whether such changes may be affected by diet. Specifically, we cross-sectionally examined steady state metabolite concentrations from a range of tissues (plasma, brown adipose tissue, cerebellum, striatum, liver, white adipose tissue, using an established liquid chromatography-mass spectrometry pipeline, from cohorts of 8 month old mutant and wild-type littermate mice that were fed one of two different high-fat diets. The differential response to diet highlighted a proportion of metabolites in all tissues, ranging from 3% (7/219 in the striatum to 12% (25/212 in white adipose tissue. By contrast, the mutant CAG-expanded allele primarily affected brain metabolites, with 14% (30/219 of metabolites significantly altered, compared to wild-type, in striatum and 11% (25/224 in the cerebellum. In general, diet and the CAG-expanded allele both elicited metabolite changes that were predominantly tissue-specific and non-overlapping, with evidence for mutation-by-diet interaction in peripheral tissues most affected by diet. Machine-learning approaches highlighted the accumulation of diverse lipid species as the most genotype-predictive metabolite changes in the striatum. Validation experiments in cell culture demonstrated that lipid accumulation was also a defining feature of mutant HdhQ111 striatal progenitor cells. Thus, metabolite-level responses to the CAG expansion mutation in vivo were tissue specific and

  7. Temporary arthrodesis using fixator rods in two-stage revision of septic knee prothesis with severe bone and tissue defects.

    Science.gov (United States)

    Röhner, Eric; Pfitzner, Tilman; Preininger, Bernd; Zippelius, Timo; Perka, Carsten

    2016-01-01

    The present study describes a new temporary arthrodesis procedure, which aims for septic knee prosthesis replacement, in particular for larger bone and soft tissue defects. Our technique offers high stability and full weight-bearing capacity of the knee joint. The study included 16 patients with major bone defects (AORI type IIb or greater) after receiving a radical debridement and a septic two-stage revision total knee arthroplasty. After removing the infected prosthesis and debridement, two AO fixator rods were positioned into the intramedullary space of the femur and tibia. Subsequently, both rods were joined tube-to-tube and adjusted in the center of the knee joint. Finally, the whole cavity of the knee joint was filled with PMMA. The number of previous surgeries, bacterial spectrum, risk factors for further infection and reinfection rates was recorded. Immediately after the temporary arthrodesis, radiographs of the knee with the enclosed spacers were taken in order to compare to previous radiographs and avoiding to miss possible spacer loosening. Nine of sixteen patients underwent more than two revision surgeries before receiving our new arthrodesis technique. No cases of spacer loosening were observed in all 16 patients; further, there were no peri-implant fractures, and four persistent infections were noted. Temporary arthrodesis using AO fixator rods offers a high stability without loosening. Its potential to replace conventional augmentation techniques should be taken into account, particularly in the case of larger bone and tissue defects. In clinical practice, the cemented spacer using AO fixator rods could be an alternative technique for temporary knee arthrodesis after septic debridement. Retrospective case series, Level IV.

  8. Recovery of Peripheral Nerve with Massive Loss Defect by Tissue Engineered Guiding Regenerative Gel

    Directory of Open Access Journals (Sweden)

    Shimon Rochkind

    2014-01-01

    Full Text Available Objective. Guiding Regeneration Gel (GRG was developed in response to the clinical need of improving treatment for peripheral nerve injuries and helping patients regenerate massive regional losses in peripheral nerves. The efficacy of GRG based on tissue engineering technology for the treatment of complete peripheral nerve injury with significant loss defect was investigated. Background. Many severe peripheral nerve injuries can only be treated through surgical reconstructive procedures. Such procedures are challenging, since functional recovery is slow and can be unsatisfactory. One of the most promising solutions already in clinical practice is synthetic nerve conduits connecting the ends of damaged nerve supporting nerve regeneration. However, this solution still does not enable recovery of massive nerve loss defect. The proposed technology is a biocompatible and biodegradable gel enhancing axonal growth and nerve regeneration. It is composed of a complex of substances comprising transparent, highly viscous gel resembling the extracellular matrix that is almost impermeable to liquids and gasses, flexible, elastic, malleable, and adaptable to various shapes and formats. Preclinical study on rat model of peripheral nerve injury showed that GRG enhanced nerve regeneration when placed in nerve conduits, enabling recovery of massive nerve loss, previously unbridgeable, and enabled nerve regeneration at least as good as with autologous nerve graft “gold standard” treatment.

  9. Reverse Tissue Expansion in Gastroschisis: What to do if the Defect is too large to close after Silo Removal?

    Science.gov (United States)

    T Adikibi, Boma; O'Toole, Stuart

    2014-01-01

    A female baby with an antenatal diagnosis of gastroschisis was transferred to our institution. The defect was large but the bowel was in good condition and a silo was placed. After successful reduction of the bowel the abdominal wall defect was too large to allow fascial or even skin closure. We utilised a Gore-tex patch with two prolene purse string sutures placed concentrically to enable the diameter of the patch to be sequentially reduced. This enabled gradual stretching of the tissues with a progressive reduction in the size of the defect. The patch was removed after 8 days and a delayed fascial closure was achieved.

  10. Gene expression in cardiac tissues from infants with idiopathic conotruncal defects

    Directory of Open Access Journals (Sweden)

    Lofland Gary K

    2011-01-01

    Full Text Available Abstract Background Tetralogy of Fallot (TOF is the most commonly observed conotruncal congenital heart defect. Treatment of these patients has evolved dramatically in the last few decades, yet a genetic explanation is lacking for the failure of cardiac development for the majority of children with TOF. Our goal was to perform genome wide analyses and characterize expression patterns in cardiovascular tissue (right ventricle, pulmonary valve and pulmonary artery obtained at the time of reconstructive surgery from 19 children with tetralogy of Fallot. Methods We employed genome wide gene expression microarrays to characterize cardiovascular tissue (right ventricle, pulmonary valve and pulmonary artery obtained at the time of reconstructive surgery from 19 children with TOF (16 idiopathic and three with 22q11.2 deletions and compared gene expression patterns to normally developing subjects. Results We detected a signal from approximately 26,000 probes reflecting expression from about half of all genes, ranging from 35% to 49% of array probes in the three tissues. More than 1,000 genes had a 2-fold change in expression in the right ventricle (RV of children with TOF as compared to the RV from matched control infants. Most of these genes were involved in compensatory functions (e.g., hypertrophy, cardiac fibrosis and cardiac dilation. However, two canonical pathways involved in spatial and temporal cell differentiation (WNT, p = 0.017 and Notch, p = 0.003 appeared to be generally suppressed. Conclusions The suppression of developmental networks may represent a remnant of a broad malfunction of regulatory pathways leading to inaccurate boundary formation and improper structural development in the embryonic heart. We suggest that small tissue specific genomic and/or epigenetic fluctuations could be cumulative, leading to regulatory network disruption and failure of proper cardiac development.

  11. Intraarticular Hyaluronic Acid Injection after Microfracture Technique for the Management of Full-Thickness Cartilage Defects Does Not Improve the Quality of Repair Tissue

    Science.gov (United States)

    Bostan, Bora; Erdem, Mehmet; Koseoglu, Resid Dogan; Asci, Murat; Sen, Cengiz

    2012-01-01

    Objective: Tissue repair that occurs after microfracture does not include hyaline-like cartilage. Therefore, other treatment modalities must be combined with microfracture to improve repair tissue quality. In this study, we combined exogenous hyaluronic acid with microfracture. Design: Thirty mature New Zealand rabbits were randomly divided into 3 groups as control, microfracture (MF), and microfracture and hyaluronic acid (MFHA). Four-millimetre full-thickness cartilage defects were created in the medial femoral condyle of each rabbit. Microfracture was performed on defects in the MF and MFHA groups. At 1 week following surgery, 1 mL of saline was injected into the knees of the control and MF groups, whereas 1 mL (15 mg/mL) hyaluronic acid was injected into the knees of the MFHA group 3 times weekly. At 6 months postsurgery, defects were evaluated according to the ICRS (International Cartilage Repair Society) and Wakitani scales. Results: According to the ICRS and Wakitani scales, the quality of repair tissue was improved in MF and MFHA groups as compared the control group (P = 0.001 and 0.001, respectively). No significant difference was observed between the MF and MFHA groups (P = 0.342). Conclusions: According to the model in this study, no beneficial effect was obtained when HA injection was combined with microfracture in the treatment of full-thickness cartilage defects. PMID:26069616

  12. Bimaxillary protrusion with an atrophic alveolar defect: orthodontics, autogenous chin-block graft, soft tissue augmentation, and an implant.

    Science.gov (United States)

    Chiu, Grace S C; Chang, Chris H N; Roberts, W Eugene

    2015-01-01

    Bimaxillary protrusion in a 28-year-old woman was complicated by multiple missing, restoratively compromised, or hopeless teeth. The maxillary right central incisor had a history of avulsion and replantation that subsequently evolved into generalized external root resorption with Class III mobility and severe loss of the supporting periodontium. This complex malocclusion had a discrepancy index of 21, and 8 additional points were scored for the atrophic dental implant site (maxillary right central incisor). The comprehensive treatment plan included extraction of 4 teeth (both maxillary first premolars, the maxillary right central incisor, and the mandibular right first molar), orthodontic closure of all spaces except for the future implant site (maxillary right central incisor), augmentation of the alveolar defect with an autogenous chin-block graft, enhancement of the gingival biotype with a connective tissue graft, and an implant-supported prosthesis. Orthodontists must understand the limitations of bone grafts. Augmented alveolar defects are slow to completely turn over to living bone, so they are usually good sites for implants but respond poorly to orthodontic space closure. However, postsurgical orthodontic treatment is often indicated to optimally finish the esthetic zone before placing the final prosthesis. The latter was effectively performed for this patient, resulting in a total treatment time of about 36 months for comprehensive interdisciplinary care. An excellent functional and esthetic result was achieved. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  13. Effects of nitrofurazone on correction of abdominal wall defect treated with polypropylene mesh involved by fibrous tissue.

    Science.gov (United States)

    Yasojima, Edson Yuzur; Ribeiro Júnior, Rubens Fernando Gonçalves; Pessôa, Thyago Cezar Prado; Cavalcante, Lainy Carollyne da Costa; Ramos, Suzana Rodrigues; Serruya, Yuri Aarão Amaral; de Moraes, Mateus Malta

    2015-10-01

    To evaluate the effects of nitrofurazone on the correction of abdominal wall defect treated with polypropylene mesh involved by fibrous tissue in rats. A defect in the abdominal wall was created and corrected with polypropylene mesh in 20 rats. They were randomly distributed into four groups: control, fibrous mesh, nitrofurazone and nitrofurazone dip in the mesh. Euthanasia was performed in 21 post-operative days. The healing process was analyzed regarding the meshes and macroscopic and microscopic aspects. All animals had adhesions. However, no statistically significant difference (p>0.05) when compared between groups. Similarly microscopic analysis, in which there was no statistical significance level for the evaluated parameters such as mono and polymorphonuclear lymphocytes, granuloma, fibrosis, necrosis and collagen proliferation. There was no significant effect on the abdominal wall defect repair with polypropylene mesh surrounded by fibrous tissue when dipped in nitrofurazone 2%.

  14. [The application of microvascular anastomotic coupler in vascular anastomosis of free tissue flap for reconstruction of defect after head and neck cancer resection].

    Science.gov (United States)

    Zhang, Y J; Wang, Z H; Li, C H; Chen, J

    2017-09-07

    Objective: To investigate the application and operation skills in vein anastomosis by microvascular anastomotic coupler (MAC) in reconstruction of defects after head and neck cancer resection. Methods: From August 2015 to July 2016, in Department of Head and Neck Surgery, Sichuan Cancer Hosipital, 17 cases underwent the reconstruction of defects after head and neck cancer resection with free tissue flaps, including forearm flaps in 11 casess, anterolateral flaps in 4 casess and fibula flaps in 2 casess. Totally 17 MAC were used, including 14 MAC for end-to-end anastomosis and 3 MAC for end-to-side anastomosis. SPSS 22.0 software was used to analyze the data. Results: Venous anastomoses in 17 free tissue flaps were successfully completed, with no anastomotic errhysis. All flaps survived well. The time required for vascular anastomoses with MAC varied 2-9 min, with average time of (4.2±2.3) min, which was significantly shorter than that with manually anastomosis (17.4 ± 2.7) min ( t =15.1, P anastomosis in free tissue flap for reconstruction of defect after head and neck cancer resection, which requires for less operation time and shows good results.

  15. Estimation of sensitivity of island fasciocutaneous neurovascular medial plantar flap in the reconstruction of soft tissue defects in calcaneal region

    Directory of Open Access Journals (Sweden)

    Jevtović Dobrica

    2002-01-01

    Full Text Available The soft tissue cover in the calcaneal region represents one of the great problems in the reconstructive surgery. The distant skin, muscle and musculocutaneous flaps are subjected to ulcers even with the orthopedic shoes. The island fasciocutaneus mid sole neurocutaneous flap can be a good substitute for the soft tissue cover due to its anatomic structure. The flap has the required dimensions, sticks well to the bone and the movements and mobility of the patient is unrestricted. This paper analyses the sensitivity of the transposed flap and the sole distal to the secondary defect observed in 30 patients. The evaluation was made after tactile tests, two-point discrimination test, the warm-cold test, the electrostatus of medial plantar nerve (MPN, and the ninhydrin test. All the tests, including the electrostatus MPN, done after 3 weeks and 3 months after the surgery, showed successful recovery of sensitivity in the transposed medial plantar flap. The results monitored after three months showed that the speed of the neural conduction recovery was 70% of normal neural reaction speed of the MPN. The modified operative techniques provide safe dissection of the plantar nerve with minimal neuropraxia. The postoperative recovery of sensitivity was more rapid, and without loss of sensitivity on the sole.

  16. Expression of defective measles virus genes in brain tissues of patients with subacute sclerosing panencephalitis

    International Nuclear Information System (INIS)

    Baczko, K.; Liebert, U.G.; Billeter, M.; Cattaneo, R.; Budka, H.; Ter Meulen, V.

    1986-01-01

    The persistence of measles virus in selected areas of the brains of four patients with subacute sclerosing panencephalitis (SSPE) was characterized by immunohistological and biochemical techniques. The five measles virus structural proteins were never simultaneously detectable in any of the bran sections. Nucleocapsid proteins and phosphoproteins were found in every diseased brain area, whereas hemagglutinin protein was detected in two cases, fusion protein was detected in three cases, and matrix protein was detected in only one case. Also, it could be shown that the amounts of measles virus RNA in the brains differed from patient to patient and in the different regions investigated. In all patients, plus-strand RNAs specific for these five viral genes could be detected. However, the amounts of fusion and hemagglutinin mRNAs were low compared with the amounts in lytically infected cells. The presence of particular measles virus RNAs in SSPE-infected brains did not always correlate with mRNA activity. In in vitro translations, the matrix protein was produced in only one case, and the hemagglutinin protein was produced in none. These results indicate that measles virus persistence in SSPE is correlated with different defects of several genes which probably prevent assembly of viral particles in SSPE-infected brain tissue

  17. Accuracy of Intraoral Digital Impressions for Whole Upper Jaws, Including Full Dentitions and Palatal Soft Tissues.

    Science.gov (United States)

    Gan, Ning; Xiong, Yaoyang; Jiao, Ting

    2016-01-01

    Intraoral digital impressions have been stated to meet the clinical requirements for some teeth-supported restorations, though fewer evidences were proposed for larger scanning range. The aim of this study was to compare the accuracy (trueness and precision) of intraoral digital impressions for whole upper jaws, including the full dentitions and palatal soft tissues, as well as to determine the effect of different palatal vault height or arch width on accuracy of intraoral digital impressions. Thirty-two volunteers were divided into three groups according to the palatal vault height or arch width. Each volunteer received three scans with TRIOS intraoral scanner and one conventional impression of whole upper jaw. Three-dimensional (3D) images digitized from conventional gypsum casts by a laboratory scanner were chose as the reference models. All datasets were imported to a specific software program for 3D analysis by "best fit alignment" and "3D compare" process. Color-coded deviation maps showed qualitative visualization of the deviations. For the digital impressions for palatal soft tissues, trueness was (130.54±33.95)μm and precision was (55.26±11.21)μm. For the digital impressions for upper full dentitions, trueness was (80.01±17.78)μm and precision was (59.52±11.29)μm. Larger deviations were found between intraoral digital impressions and conventional impressions in the areas of palatal soft tissues than that in the areas of full dentitions (pimpressions for palatal soft tissues was slightly better than that for full dentitions (p = 0.049). There was no significant effect of palatal vault height on accuracy of digital impressions for palatal soft tissues (p>0.05), but arch width was found to have a significant effect on precision of intraoral digital impressions for full dentitions (p = 0.016). A linear correlation was found between arch width and precision of digital impressions for whole upper jaws (r = 0.326, p = 0.034 for palatal soft tissues and r

  18. Alveolar bone tissue engineering in critical-size defects of experimental animal models: a systematic review and meta-analysis.

    Science.gov (United States)

    Shanbhag, Siddharth; Pandis, Nikolaos; Mustafa, Kamal; Nyengaard, Jens R; Stavropoulos, Andreas

    2017-10-01

    Regeneration of large, 'critical-size' bone defects remains a clinical challenge. Bone tissue engineering (BTE) is emerging as a promising alternative to autogenous, allogeneic and biomaterial-based bone grafting. The objective of this systematic review was to answer the focused question: in animal models, do cell-based BTE strategies enhance regeneration in alveolar bone critical-size defects (CSDs), compared with grafting with only biomaterial scaffolds or autogenous bone? Following PRISMA guidelines, electronic databases were searched for controlled animal studies reporting maxillary or mandibular CSD and implantation of mesenchymal stem cells (MSCs) or osteoblasts (OBs) seeded on biomaterial scaffolds. A random effects meta-analysis was performed for the outcome histomorphometric new bone formation (%NBF). Thirty-six studies were included that reported on large- (monkeys, dogs, sheep, minipigs) and small-animal (rabbits, rats) models. On average, studies presented with an unclear-to-high risk of bias and short observation times. In most studies, MSCs or OBs were used in combination with alloplastic mineral-phase scaffolds. In five studies, cells were modified by ex vivo gene transfer of bone morphogenetic proteins (BMPs). The meta-analysis indicated statistically significant benefits in favour of: (1) cell-loaded vs. cell-free scaffolds [weighted mean difference (WMD) 15.59-49.15% and 8.60-13.85% NBF in large- and small-animal models, respectively]; and (2) BMP-gene-modified vs. unmodified cells (WMD 10.06-20.83% NBF in small-animal models). Results of cell-loaded scaffolds vs. autogenous bone were inconclusive. Overall, heterogeneity in the meta-analysis was high (I 2  > 90%). In summary, alveolar bone regeneration is enhanced by addition of osteogenic cells to biomaterial scaffolds. The direction and estimates of treatment effect are useful to predict therapeutic efficacy and guide future clinical trials of BTE. Copyright © 2016 John Wiley & Sons, Ltd

  19. Tissue specific mutagenic and carcinogenic responses in NER defective mouse models.

    NARCIS (Netherlands)

    Wijnhoven, Susan W P; Hoogervorst, Esther M; Waard, Harm de; Horst, Gijsbertus T J van der; Steeg, Harry van

    2007-01-01

    Several mouse models with defects in genes encoding components of the nucleotide excision repair (NER) pathway have been developed. In NER two different sub-pathways are known, i.e. transcription-coupled repair (TC-NER) and global-genome repair (GG-NER). A defect in one particular NER protein can

  20. A multiscale model for glioma spread including cell-tissue interactions and proliferation.

    Science.gov (United States)

    Engwer, Christian; Knappitsch, Markus; Surulescu, Christina

    2016-04-01

    Glioma is a broad class of brain and spinal cord tumors arising from glia cells, which are the main brain cells that can develop into neoplasms. They are highly invasive and lead to irregular tumor margins which are not precisely identifiable by medical imaging, thus rendering a precise enough resection very difficult. The understanding of glioma spread patterns is hence essential for both radiological therapy as well as surgical treatment. In this paper we propose a multiscale model for glioma growth including interactions of the cells with the underlying tissue network, along with proliferative effects. Our current accounting for two subpopulations of cells to accomodate proliferation according to the go-or-grow dichtomoty is an extension of the setting in [16]. As in that paper, we assume that cancer cells use neuronal fiber tracts as invasive pathways. Hence, the individual structure of brain tissue seems to be decisive for the tumor spread. Diffusion tensor imaging (DTI) is able to provide such information, thus opening the way for patient specific modeling of glioma invasion. Starting from a multiscale model involving subcellular (microscopic) and individual (mesoscale) cell dynamics, we perform a parabolic scaling to obtain an approximating reaction-diffusion-transport equation on the macroscale of the tumor cell population. Numerical simulations based on DTI data are carried out in order to assess the performance of our modeling approach.

  1. [Clinical application of free vascularized flaps based on the wrist cutaneous branch of ulnar artery in repairing finger soft tissue defect].

    Science.gov (United States)

    Tang, Yang-Hua; Zeng, Lin-Ru; Huang, Zhong-Ming; Yue, Zhen-Shuang; Xu, Can-Da; Xin, Da-Wei

    2014-09-01

    To investigate the methods and clinical effects of repairing finger soft tissue defect with free vascularized flaps based on the wrist cutaneous branch of ulnar artery. From February 2010 to December 2012, 16 patients with finger soft tissue defects were repaired by free vascularized flaps based on the wrist cutaneous branch of ulnar artery, including 10 males and 6 females with an average age of 38.2 years old ranging from 18 to 52 years. Among them, 5 cases caused by hot crush injury, 8 cases caused by machine crush injury, 3 cases caused by firecracker burst injury. The defect area varied from 1.3 cm x 2.3 cm to 2.6 cm x 5.0 cm. The flap area varied from 1.5 cm x 2.5 cm to 2.8 cm x 5.2 cm. The appearance and two-point discrimination of flap were observed after operation. All flaps survived and wounds healed primarily. No wound infection and skin necrosis were found in donor site and recipient site. Among repair methods, direct suture in forearm donor site had 11 cases and skin graft had 5 cases. All patients were followed up from 6 to 24 months with an average of 10.8 months. The appearance of flap was not fat or clumsy, texture and color were similar to the recipient site, the sensation were good, two-point discrimination was 6 to 9 mm. The appearance of donor site were well complicated with mild scarring without dysfunction obviously. The free vascularized flaps based on the wrist cutaneous branch of ulnar artery has the advantages of vascular anatomy constant,thickness moderate and carry sensory nerves, etc, which is effective way to repair finger soft tissue defects.

  2. Plastic surgery for large wound defects using vascularized flops in treatment of skin and soft-tissue tumors

    International Nuclear Information System (INIS)

    Korotkevich, E.A.; Zalutskij, I.V.; Ismail-Zade, R.S.; Frolov, G.N.

    1992-01-01

    The results were presented on plastic and reconstructive -anaplastic surgery in resection of locally spread and relapse tumors of the skin and soft tissues after multiple courses of radiation and combined treatment. 38 patients with skin melanoma and softtissue sarcomas received radio- and/or chemotherapy in preoperative period under conditions of local hyperthermia of the tumor. Two types of plasty of large wound defects using vascularized flaps were considered

  3. Use of cyanoacrylate as barrier in guided tissue regeneration in class II furcation defects

    Directory of Open Access Journals (Sweden)

    Carmen L Mueller Storrer

    2014-01-01

    Full Text Available The guided bone regeneration (GBR is a technique that uses resorbable and non-resorbable membranes in association with other filling biomaterials. GBR is one of the optional treatments for therapy of class II furcation defects. The current case report evaluates clinically and radiographically the use of the cyanoacrylate membrane (Glubran ®2 associated with organic bovine bone (GenOx for the treatment of vestibular class II furcation defect on the lower left molar. Conclusion: The GBR is an option in the treatment of vestibular class II furcation defects and cyanoacrylate surgical glue, acting as a mechanic barrier and providing an efficient stability for the graft.

  4. Mutations in TKT Are the Cause of a Syndrome Including Short Stature, Developmental Delay, and Congenital Heart Defects.

    Science.gov (United States)

    Boyle, Lia; Wamelink, Mirjam M C; Salomons, Gajja S; Roos, Birthe; Pop, Ana; Dauber, Andrew; Hwa, Vivian; Andrew, Melissa; Douglas, Jessica; Feingold, Murray; Kramer, Nancy; Saitta, Sulagna; Retterer, Kyle; Cho, Megan T; Begtrup, Amber; Monaghan, Kristin G; Wynn, Julia; Chung, Wendy K

    2016-06-02

    Whole-exome sequencing (WES) is increasingly being utilized to diagnose individuals with undiagnosed disorders. Developmental delay and short stature are common clinical indications for WES. We performed WES in three families, using proband-parent trios and two additional affected siblings. We identified a syndrome due to an autosomal-recessively inherited deficiency of transketolase, encoded by TKT, on chromosome 3p21. Our series includes three families with a total of five affected individuals, ranging in age from 4 to 25 years. Two families of Ashkenazi Jewish ancestry were homozygous for an 18 base pair in-frame insertion in TKT. The third family was compound heterozygous for nonsense and missense variants in TKT. All affected individuals had short stature and were developmentally delayed. Congenital heart defects were noted in four of the five affected individuals, and there was a history of chronic diarrhea and cataracts in the older individuals with the homozygous 18 base pair insertion. Enzymatic testing confirmed significantly reduced transketolase activity. Elevated urinary excretion of erythritol, arabitol, ribitol, and pent(ul)ose-5-phosphates was detected, as well as elevated amounts of erythritol, arabitol, and ribitol in the plasma of affected individuals. Transketolase deficiency reduces NADPH synthesis and nucleic acid synthesis and cell division and could explain the problems with growth. NADPH is also critical for maintaining cerebral glutathione, which might contribute to the neurodevelopmental delays. Transketolase deficiency is one of a growing list of inborn errors of metabolism in the non-oxidative part of the pentose phosphate pathway. Copyright © 2016 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  5. A composite critical-size rabbit mandibular defect for evaluation of craniofacial tissue regeneration

    NARCIS (Netherlands)

    Shah, S.R.; Young, S.; Goldman, J.L.; Jansen, J.A.; Wong, M.E.; Mikos, A.G.

    2016-01-01

    Translational biomaterials targeted toward the regeneration of large bone defects in the mandible require a preclinical model that accurately recapitulates the regenerative challenges present in humans. Computational modeling and in vitro assays do not fully replicate the in vivo environment.

  6. Reconstruction of radial bone defects using the reinforced tissue-engineered periosteum: an experimental study on rabbit weightbearing segment.

    Science.gov (United States)

    Guo, Honggang; Li, Xiaomian; Yuan, Xiaoyan; Ma, Xinlong

    2012-02-01

    The objective of this study was to compare the osteogenic potential of reinforced and conventional tissue-engineered periosteum. Adipose-derived stromal cells of rabbits were induced into osteoblasts. Osteoinduced cells were seeded onto chitosan-tricalcium-phosphate-gelatin (Cs-TCP-Gel) and chitosan (Cs) scaffold, thus constructing the reinforced and conventional tissue-engineered periostea, respectively. Alkaline phosphatase (ALP) and von Kossa staining protocols were used to assess osteoblast phenotype.We surgically created a 15-mm-long bone defect in the right radii of New Zealand rabbits. The defects were treated with reinforced biomimetic periosteum in group A (n = 30) and treated with conventional tissue-engineered periosteum in group B (n = 30).Group C (n = 30) received CS-TCP-Gel scaffold alone, and group D (n = 30) served as untreated side (sham group). Radiologic,histologic, immunohistochemical, and histomorphometric studies were used to analyze healing pattern. ALP was remarkably expressed in the osteoinduced cells, indicating that osteoblastic differentiation was stable. Extracellular matrix calcification with dark nodule was detected by von Kossa staining. Compared with groups B and C, histologic results demonstrated that de novo osteogenesis proliferated in group A at 4 weeks. This was further confirmed by radiographic findings, which displayed the segmental gap completely healed by mature bone at 12 weeks. Robust expression of bone morphogenetic protein-2 in group A was also evident, whereas group D displayed poor osteogenic performance. Furthermore, histomorphometric and biomechanical results in group A demonstrated statistical significance over those in other groups (p 0.05). Our findings show that the reinforced tissue-engineered periosteum is superior to conventional one as a better biomimetic tissue,further indicating that it can repair the weight-bearing defects. Copyright © 2012 by LippincottWilliams & Wilkins

  7. Sulfamethoxazole-Trimethoprim (Cotrimoxazole) for Skin and Soft Tissue Infections Including Impetigo, Cellulitis, and Abscess.

    Science.gov (United States)

    Bowen, Asha C; Carapetis, Jonathan R; Currie, Bart J; Fowler, Vance; Chambers, Henry F; Tong, Steven Y C

    2017-01-01

    Skin and soft tissue infections (SSTI) affect millions of people globally, which represents a significant burden on ambulatory care and hospital settings. The role of sulfamethoxazole-trimethoprim (SXT) in SSTI treatment, particularly when group A Streptococcus (GAS) is involved, is controversial. We conducted a systematic review of clinical trials and observational studies that address the utility of SXT for SSTI treatment, caused by either GAS or Staphylococcus aureus , including methicillin-resistant (MRSA). We identified 196 studies, and 15 underwent full text review by 2 reviewers. Observational studies, which mainly focused on SSTI due to S aureus , supported the use of SXT when compared with clindamycin or β-lactams. Of 10 randomized controlled trials, 8 demonstrated the efficacy of SXT for SSTI treatment including conditions involving GAS. These findings support SXT use for treatment of impetigo and purulent cellulitis (without an additional β-lactam agent) and abscess and wound infection. For nonpurulent cellulitis, β-lactams remain the treatment of choice.

  8. Nonwoven-based gelatin/polycaprolactone membrane proves suitability in a preclinical assessment for treatment of soft tissue defects.

    Science.gov (United States)

    Schulz, Simon; Angarano, Marco; Fabritius, Martin; Mülhaupt, Rolf; Dard, Michel; Obrecht, Marcel; Tomakidi, Pascal; Steinberg, Thorsten

    2014-07-01

    Standard preclinical assessments in vitro often have limitations regarding their transferability to human beings, mainly evoked by their nonhuman and tissue-different/nontissue-specific source. Here, we aimed at employing tissue-authentic simple and complex interactive fibroblast-epithelial cell systems and their in vivo-relevant biomarkers for preclinical in vitro assessment of nonwoven-based gelatin/polycaprolactone membranes (NBMs) for treatment of soft tissue defects. NBMs were composed of electrospun gelatin and polycaprolactone nanofiber nonwovens. Scanning electron microscopy in conjunction with actin/focal contact integrin fluorescence revealed successful adhesion and proper morphogenesis of keratinocytes and fibroblasts, along with cells' derived extracellular matrix deposits. The "feel-good factor" of cells under study on the NBM was substantiated by forming a confluent connective tissue entity, which was concomitant with a stratified epithelial equivalent. Immunohistochemistry proved tissue authenticity over time by abundance of the biomarker vimentin in the connective tissue entity, and chronological increase of keratins KRT1/10 and involucrin expression in epithelial equivalents. Suitability of the novel NBM as wound dressing was evidenced by an almost completion of epithelial wound closure in a pilot mini-pig study, after a surgical intervention-caused gingival dehiscence. In summary, preclinical assessment by tissue-authentic cell systems and the animal pilot study revealed the NBM as an encouraging therapeutic medical device for prospective clinical applications.

  9. Repair of segmental bone defect using Totally Vitalized tissue engineered bone graft by a combined perfusion seeding and culture system.

    Directory of Open Access Journals (Sweden)

    Lin Wang

    Full Text Available BACKGROUND: The basic strategy to construct tissue engineered bone graft (TEBG is to combine osteoblastic cells with three dimensional (3D scaffold. Based on this strategy, we proposed the "Totally Vitalized TEBG" (TV-TEBG which was characterized by abundant and homogenously distributed cells with enhanced cell proliferation and differentiation and further investigated its biological performance in repairing segmental bone defect. METHODS: In this study, we constructed the TV-TEBG with the combination of customized flow perfusion seeding/culture system and β-tricalcium phosphate (β-TCP scaffold fabricated by Rapid Prototyping (RP technique. We systemically compared three kinds of TEBG constructed by perfusion seeding and perfusion culture (PSPC method, static seeding and perfusion culture (SSPC method, and static seeding and static culture (SSSC method for their in vitro performance and bone defect healing efficacy with a rabbit model. RESULTS: Our study has demonstrated that TEBG constructed by PSPC method exhibited better biological properties with higher daily D-glucose consumption, increased cell proliferation and differentiation, and better cell distribution, indicating the successful construction of TV-TEBG. After implanted into rabbit radius defects for 12 weeks, PSPC group exerted higher X-ray score close to autograft, much greater mechanical property evidenced by the biomechanical testing and significantly higher new bone formation as shown by histological analysis compared with the other two groups, and eventually obtained favorable healing efficacy of the segmental bone defect that was the closest to autograft transplantation. CONCLUSION: This study demonstrated the feasibility of TV-TEBG construction with combination of perfusion seeding, perfusion culture and RP technique which exerted excellent biological properties. The application of TV-TEBG may become a preferred candidate for segmental bone defect repair in orthopedic and

  10. A comparative study of tissue-engineered constructs from Acropora and Porites coral in a large animal bone defect model

    Science.gov (United States)

    Manassero, M.; Bensidhoum, M.; Lecuelle, B.; Logeart-Avramoglou, D.; Petite, H.; Viateau, V.

    2017-01-01

    Objectives To compare the therapeutic potential of tissue-engineered constructs (TECs) combining mesenchymal stem cells (MSCs) and coral granules from either Acropora or Porites to repair large bone defects. Materials and Methods Bone marrow-derived, autologous MSCs were seeded on Acropora or Porites coral granules in a perfusion bioreactor. Acropora-TECs (n = 7), Porites-TECs (n = 6) and bone autografts (n = 2) were then implanted into 25 mm long metatarsal diaphyseal defects in sheep. Bimonthly radiographic follow-up was completed until killing four months post-operatively. Explants were subsequently processed for microCT and histology to assess bone formation and coral bioresorption. Statistical analyses comprised Mann-Whitney, t-test and Kruskal–Wallis tests. Data were expressed as mean and standard deviation. Results A two-fold increaseof newly formed bone volume was observed for Acropora-TECs when compared with Porites-TECs (14 sd 1089 mm3 versus 782 sd 507 mm3; p = 0.09). Bone union was consistent with autograft (1960 sd 518 mm3). The kinetics of bioresorption and bioresorption rates at four months were different for Acropora-TECs and Porites-TECs (81% sd 5% versus 94% sd 6%; p = 0.04). In comparing the defects that healed with those that did not, we observed that, when major bioresorption of coral at two months occurs and a scaffold material bioresorption rate superior to 90% at four months is achieved, bone nonunion consistently occurred using coral-based TECs. Discussion Bone regeneration in critical-size defects could be obtained with full bioresorption of the scaffold using coral-based TECs in a large animal model. The superior performance of Acropora-TECs brings us closer to a clinical application, probably because of more suitable bioresorption kinetics. However, nonunion still occurred in nearly half of the bone defects. Cite this article: A. Decambron, M. Manassero, M. Bensidhoum, B. Lecuelle, D. Logeart-Avramoglou, H. Petite, V. Viateau. A

  11. Usefulness of pulse-wave doppler tissue sampling and dobutamine stress echocardiography for identification of false positive inferior wall defects in SPECT

    International Nuclear Information System (INIS)

    Altinmakas, S.; Dagdeviren, B.; Turkmen, M.; Gursurer, M.; Say, B.; Tezel, T.; Ersek, B.

    2000-01-01

    False positive inferior wall perfusion defects restrict the accuracy of SPECT in diagnosis of coronary artery disease (CAD). Pulse-Wave Tissue Doppler (PWTD) has been recently proposed to assess regional wall motion velocities. The objectives of this study were to evaluate the presence of CAD by using PWTD during dobutamine stress echocardiography (DSE) in patients with an inferior perfusion defect detected by SPECT and compare PWTD parameters of normal cases with patients who had inferior perfusion defect and CAD. Sixty-five patients (mean age 58±8 years, 30 men) with a normal LV systolic function at rest according to echocardiographic evaluation with an inferior ischemia determined by SPECT and a control group (CG) of 34 normal cases (mean age 56±7 years, 16 men) were included in this study. All patients underwent a standard DSE (up to 40 μg/kg/min with additional atropine during sub-maximum heart rate responses). Pulse-wave Doppler tissue sampling of inferior wall was performed in the apical 2-chamber view at rest and stress. The coronary angiography was performed within 24 hours. The results were evaluated for the prediction of significant right coronary artery (RCA) and/or left circumflex coronary artery (CX) with narrowing (≥50% diameter stenosis, assessed by quantitative coronary angiography). It was observed that the peak stress mean E/A ratio was lower in patients with CAD when compared to patients without CAD (0.78±0.2 versus 1.29±0.11 p<0.0001). Also the peak stress E/A ratio of normal cases was significantly higher than patients who had CAD (1.19±0.3 versus 0.78±0.2 p<0.0001). When the cut off point for the E/A ratio was determined as 1, the sensitivity and specificity of dobutamine stress PWTD E/A were 89% and 86%, respectively. The peak stress E/A ratio was higher than 1 in all patients with a false positive perfusion defect. Systolic S velocity increase during DSE was significantly lower in patients with CAD (54%±17 versus 99%±24 p=0

  12. [Repair of skin and soft tissue defects at distal end of finger and donor site with relaying reversed perforator flaps].

    Science.gov (United States)

    Deng, Chengliang; Wei, Zairong; Sun, Guangfeng; Tang, Xiujun; Jin, Wenhu; Li, Hai; Wu, Bihua; Wang, Dali

    2015-04-01

    To explore the clinical effects of relaying reversed perforator flaps in repairing skin and soft tissue defects at distal end of finger and donor site. Seventeen patients (17 fingers) with skin and soft tissue defects at distal end of finger were hospitalized from June 2011 to June 2013. The reversed digital artery perforator flap with branch of digital nerve was used to repair the defect. The first donor site was repaired by dorsal metacarpal artery perforator flap; the second donor site was closed by suturing. The area of skin defect at distal end of finger ranged from 2.0 cm x 1.5 cm to 3.0 cm x 2.0 cm, and the area of digital artery perforator flap and dorsal metacarpal artery perforator flap ranged from 2.2 cm x 1.5 cm to 3.6 cm x 2.5 cm and 2.5 cm x 2.0 cm to 4.2 cm x 3.0 cm, respectively. All the 34 flaps survived completely. Cyanosis and partial necrosis of the epidermis appeared in 1 flap, which was healed after dressing change. All the patients were followed up for 1 to 18 months, with mean time of 8 months. The color, texture and appearance of flaps were satisfactory. There was no depression or breakdown in the first donor sites. Some linear scars appeared in the second donor sites, but they did not affect the general appearance. The donor sites at joint or tendon did not affect the joint activity after healing. The results of function evaluation of range of active movement of the fingers were excellent in 15 cases and good in 2 cases. The results of sensation of the flaps were S3 in 1 finger, S4 in 2 fingers, and S5 in 14 fingers. The distance of two-point discrimination of flaps ranged from 5 to 7 mm, with mean distance of 6 mm. Relaying reversed perforator flap, with reliable blood supply and both donor sites in the hand, can improve the appearance and function of the first donor site as well as repair skin and soft tissue defects at distal end of finger.

  13. Optimizing Soft Tissue Management and Spacer Design in Segmental Bone Defects

    Science.gov (United States)

    2015-10-01

    hematopoietic cells 5. Marrow area composed only of adipose tissue 6. Fibrous connective tissue 7. Hyaline cartilage 8. Void area (Express #2-8 as % of...than tissue area) *Cellularity  0 = No inflammatory cells  1 = Inflammatory cells confined to inner 10% of membrane thickness  2 = Inflammatory... stem differentiation, pluripotency, and cell -fate (Oct4, NANOG, Sox2 respectfully) as well as cytokine growth-factors (TGFβ1) and members of the

  14. Antibody-Mediated Osseous Regeneration for Bone Tissue Engineering in Canine Segmental Defects

    Directory of Open Access Journals (Sweden)

    A. Khojasteh

    2018-01-01

    Full Text Available Among many applications of therapeutic monoclonal antibodies (mAbs, a unique approach for regenerative medicine has entailed antibody-mediated osseous regeneration (AMOR. In an effort to identify a clinically relevant model of craniofacial defect, the present study investigated the efficacy of mAb specific for bone morphogenetic protein- (BMP- 2 to repair canine segmental mandibular continuity defect model. Accordingly, a 15 mm unilateral segmental defect was created in mandible and fixated with a titanium plate. Anorganic bovine bone mineral with 10% collagen (ABBM-C was functionalized with 25 μg/mL of either chimeric anti-BMP-2 mAb or isotype-matched mAb (negative control. Recombinant human (rh BMP-2 served as positive control. Morphometric analyses were performed on computed tomography (CT and histologic images. Bone densities within healed defect sites at 12 weeks after surgery were 1360.81 ± 10.52 Hounsfield Unit (HU, 1044.27 ± 141.16 HU, and 839.45 ± 179.41 HU, in sites with implanted anti-BMP-2 mAb, rhBMP-2, and isotype mAb groups, respectively. Osteoid bone formation in anti-BMP-2 mAb (42.99% ± 8.67 and rhBMP-2 (48.97% ± 2.96 groups was not significantly different but was higher (p<0.05 than in sites with isotype control mAb (26.8% ± 5.35. In view of the long-term objective of translational application of AMOR in humans, the results of the present study demonstrated the feasibility of AMOR in a large clinically relevant animal model.

  15. Use of the omentum flap as additional soft-tissue cover for abdominal wall defects reconstructed with Gore-Tex.

    Science.gov (United States)

    Wong, Chin-Ho; Tan, Bien-Keem; Koong, Heng-Nung; Lim, Chong-Hee; Chia, Sing-Joo; Song, Colin

    2005-11-01

    Use of alloplastic materials such as Gore-Tex and locoregional flaps for reconstruction of large abdominal wall defects has been well described. The purpose of this article is to present a novel technique of using the omentum as an interpositional flap to protect the Gore-Tex repair of the abdominal wall. Four patients with large abdominal wall defects underwent reconstruction with Gore-Tex and omentum flap. These defects resulted from tumor resection and recurrent incisional hernia. Their dimensions ranged from 15 x 10 cm to 25 x 27 cm. The Gore-Tex patch was inset using an underlay technique. The omentum was tunneled through a separate opening in the abdominal wall into the subcutaneous plane and used to cover the Gore-Tex. Skin coverage was accomplished by direct closure or myocutaneous flaps. The mean follow-up was 17 months. All wounds healed, with no hernias. One patient developed a subcutaneous abscess 6 months postoperatively, and this was treated successfully by percutaneous drainage, as the omentum had walled-off the abscess. The omentum flap served as an additional soft-tissue cover over the Gore-Tex repair to prevent exposure in the event of infection or flap breakdown. This technique is useful in situations in which delayed wound healing is anticipated or when large quantities of prosthetic material are used.

  16. Implantation of a novel biologic and hybridized tissue engineered bioimplant in large tendon defect: an in vivo investigation.

    Science.gov (United States)

    Oryan, Ahmad; Moshiri, Ali; Parizi, Abdolhamid Meimandi; Maffulli, Nicola

    2014-02-01

    Surgical reconstruction of large Achilles tendon defects is technically demanding. There is no standard method, and tissue engineering may be a valuable option. We investigated the effects of 3D collagen and collagen-polydioxanone sheath (PDS) implants on a large tendon defect model in rabbits. Ninety rabbits were divided into three groups: control, collagen, and collagen-PDS. In all groups, 2 cm of the left Achilles tendon were excised and discarded. A modified Kessler suture was applied to all injured tendons to retain the gap length. The control group received no graft, the treated groups were repaired using the collagen only or the collagen-PDS prostheses. The bioelectrical characteristics of the injured areas were measured at weekly intervals. The animals were euthanized at 60 days after the procedure. Gross, histopathological and ultrastructural morphology and biophysical characteristics of the injured and intact tendons were investigated. Another 90 pilot animals were also used to investigate the inflammatory response and mechanism of graft incorporation during tendon healing. The control tendons showed severe hyperemia and peritendinous adhesion, and the gastrocnemius muscle of the control animals showed severe atrophy and fibrosis, with a loose areolar connective tissue filling the injured area. The tendons receiving either collagen or collagen-PDS implants showed lower amounts of peritendinous adhesion, hyperemia and muscle atrophy, and a dense tendon filled the defect area. Compared to the control tendons, application of collagen and collagen-PDS implants significantly improved water uptake, water delivery, direct transitional electrical current and tissue resistance to direct transitional electrical current. Compared to the control tendons, both prostheses showed significantly increased diameter, density and alignment of the collagen fibrils and maturity of the tenoblasts at ultrastructure level. Both prostheses influenced favorably tendon healing

  17. TissuePatch™ as a novel synthetic sealant for repair of superficial lung defect: in vitro tests results.

    Science.gov (United States)

    Zhang, Ruoyu; Bures, Maximilian; Höffler, Hans-Klaus; Zinne, Norman; Länger, Florian; Bisdas, Theodosios; Haverich, Axel; Krüger, Marcus

    2012-11-19

    Controversies surrounding the efficacy of surgical sealants against alveolar air leaks (AAL) in lung surgery abound in the literature. We sought to test the sealing efficacy of a novel synthetic sealant, TissuePatch™ in an in vitro lung model. The lower lobe of freshly excised swine lung (n = 10) was intubated and ventilated. A superficial parenchymal defect (40 × 25 mm) was created, followed by AAL assessment. After sealant application, AAL was assessed again until burst failure occurred. The length of defect was recorded to evaluate the elasticity of the sealant. Superficial parenchymal defects resulted in AAL increasing disproportionally with ascending maximal inspiratory pressure (Pmax). Multiple linear regression analysis revealed strong correlation between AAL and Pmax, compliance, resistance. After sealant application, AAL was sealed in all ten tests at an inspired tidal volume (TVi) of 400 ml, in nine tests at TVi = 500 ml, in seven at TVi = 600 ml and in five at TVi = 700 ml. The mean burst pressure was 42 ± 9 mBar. Adhesive and cohesive sealant failures were found in six and three tests respectively. The length of defect before sealant failure was 8.9 ± 4.9% larger than that at TVi = 400 ml, demonstrating an adequate elasticity of this sealant film. TissuePatch™ may be a reliable sealant for alternative or adjunctive treatment for repair of superficial parenchymal defects in lung surgery. The clinical benefits of this sealant should be confirmed by prospective, randomised controlled clinical trials. ABSTRAKT: Die Wirksamkeit von chirurgischen Klebstoffen zur Prävention von alveolo-pleuralem Luftleck (APL) ist trotz zunehmenden klinischen Anwendungen in Lungenchirurgie immer noch kontrovers diskutiert. Wir evaluierten die Abdichtungswirksamkeit von einem neuartigen synthetischen Kleber, TissuePatch™ mittels eines in vitro Lungenmodels. METHODE: Der Unterlappen von frisch entnommenen Schweinlungen (n = 10) wurde

  18. Reconstruction of a Circumferential Upper Extremity Soft Tissue Defect With a Dermal Regeneration Template and Skin Grafting.

    Science.gov (United States)

    Son, Ji H; Bafus, Blaine; Khandelwal, Anjay; Chepla, Kyle J

    2018-03-01

    Extensive degloving injuries of the upper extremity are rare and pose unique reconstructive challenges. Circumferential loss of soft tissue coverage over the elbow treated by skin grafting is often complicated by elbow contracture and decreased range of motion, requiring secondary contracture release and free-flap reconstruction to restore function. As an alternative approach, we report a good outcome after the use of a dermal regenerative template and subsequent split-thickness skin grafting. A 38-year-old right hand dominant man presented with circumferential degloving injury of the entire right upper extremity to the level of the chest wall after an industrial accident. An immediate right transradial amputation was performed and serial debridement was required to remove all devitalized tissue. A dermal regenerative template with subsequent split-thickness skin grafting was used to cover the circumferential elbow soft tissue defect. Occupational therapy and splinting were used preoperatively and postoperatively to prevent contracture. However, axillary scar contracture release was required 4 months after injury. Six months after skin grafting, the patient had stable soft tissue coverage of the upper extremity. Shoulder motion measured 120-degree abduction and 140-degree forward flexion and elbow range of motion was 15 to 150 degrees. In this case, an excellent clinical outcome was obtained with a dermal regenerative template, aggressive wound care, and a multidisciplinary team approach.

  19. 3D printed optical phantoms and deep tissue imaging for in vivo applications including oral surgery

    Science.gov (United States)

    Bentz, Brian Z.; Costas, Alfonso; Gaind, Vaibhav; Garcia, Jose M.; Webb, Kevin J.

    2017-03-01

    Progress in developing optical imaging for biomedical applications requires customizable and often complex objects known as "phantoms" for testing, evaluation, and calibration. This work demonstrates that 3D printing is an ideal method for fabricating such objects, allowing intricate inhomogeneities to be placed at exact locations in complex or anatomically realistic geometries, a process that is difficult or impossible using molds. We show printed mouse phantoms we have fabricated for developing deep tissue fluorescence imaging methods, and measurements of both their optical and mechanical properties. Additionally, we present a printed phantom of the human mouth that we use to develop an artery localization method to assist in oral surgery.

  20. A comparative clinico-radiographic study of guided tissue regeneration with bioresorbable membrane and a composite synthetic bone graft for the treatment of periodontal osseous defects

    Directory of Open Access Journals (Sweden)

    Sumedha Srivastava

    2015-01-01

    Full Text Available Aim: The aim was to evaluate the bonefill in periodontal osseous defects with the help of guided tissue regeneration, bioresorbable membrane (PerioCol + bone graft (Grabio Glascera in combination and with bonegraft (Grabio Glascera alone. Materials and Methods: The study involved total 30 sites in systemically healthy 19 patients. The parameters for evaluation includes plaque index sulcus bleeding index with one or more periodontal osseous defects having (i probing depth (PD of ≥ 5 mm (ii clinical attachment loss (CAL of ≥ 5 mm and (iii ≥3 mm of radiographic periodontal osseous defect (iv bonefill (v crestal bone loss (vi defect resolution. The study involved the three wall and two wall defects which should be either located interproximally or involving the furcation area. The statistical analysis was done using Statistical Package for Social Sciences, the Wilcoxon signed rank statistic W + for Mann-Whitney U-test. Results: The net gain in PD and CAL after 6 months for Group I ([PerioCol] + [Grabio Glascera] and Group II (Grabio Glascera was 3.94 ± 1.81 mm, 3.57 ± 2.21 mm and 3.94 ± 1.81, 3.57 ± 2.21 mm, respectively. The results of the study for Group I and Group II with regards to mean net bonefill, was 3.25 ± 2.32 (58% mm and 5.14 ± 3.84 (40.26 ± 19.14% mm, crestal bone loss − 0.25 ± 0.68 mm and − 0.79 ± 1.19 mm. Defect resolution 3.50 ± 2.34 mm and 5.93 ± 4.01 mm, respectively. Conclusion: On comparing both the groups together after 6 months of therapy, the results were equally effective for combination of graft and membrane versus bone graft alone since no statistical significant difference was seen between above parameters for both the groups. Thus, both the treatment modalities are comparable and equally effective.

  1. Application potential of bone marrow mesenchymal stem cell (BMSCs) based tissue-engineering for spinal cord defect repair in rat fetuses with spina bifida aperta.

    Science.gov (United States)

    Li, Xiaoshuai; Yuan, Zhengwei; Wei, Xiaowei; Li, Hui; Zhao, Guifeng; Miao, Jiaoning; Wu, Di; Liu, Bo; Cao, Songying; An, Dong; Ma, Wei; Zhang, Henan; Wang, Weilin; Wang, Qiushi; Gu, Hui

    2016-04-01

    Spina bifida aperta are complex congenital malformations resulting from failure of fusion in the spinal neural tube during embryogenesis. Despite surgical repair of the defect, most patients who survive with spina bifida aperta have a multiple system handicap due to neuron deficiency of the defective spinal cord. Tissue engineering has emerged as a novel treatment for replacement of lost tissue. This study evaluated the prenatal surgical approach of transplanting a chitosan-gelatin scaffold seeded with bone marrow mesenchymal stem cells (BMSCs) in the healing the defective spinal cord of rat fetuses with retinoic acid induced spina bifida aperta. Scaffold characterisation revealed the porous structure, organic and amorphous content. This biomaterial promoted the adhesion, spreading and in vitro viability of the BMSCs. After transplantation of the scaffold combined with BMSCs, the defective region of spinal cord in rat fetuses with spina bifida aperta at E20 decreased obviously under stereomicroscopy, and the skin defect almost closed in many fetuses. The transplanted BMSCs in chitosan-gelatin scaffold survived, grew and expressed markers of neural stem cells and neurons in the defective spinal cord. In addition, the biomaterial presented high biocompatibility and slow biodegradation in vivo. In conclusion, prenatal transplantation of the scaffold combined with BMSCs could treat spinal cord defect in fetuses with spina bifida aperta by the regeneration of neurons and repairmen of defective region.

  2. The bone tissue responses to prehydrated and collagenated cortico-cancellous porcine bone grafts: a study in rabbit maxillary defects.

    Science.gov (United States)

    Nannmark, Ulf; Sennerby, Lars

    2008-12-01

    Bone substitutes should have osteoconductive properties and be completely replaced with new bone with time. Adding collagen gel to prehydrated and collagenated porcine bone (PCPB) particles results in a sticky and moldable material which facilitates clinical handling. However, the possible influence of the gel on the bone tissue response is not known. The objective of the study was to evaluate the bone tissue responses to PCPB graft with or without collagen gel and to evaluate the resorption/degradation properties of the biomaterials. Fourteen rabbits were used in the study. Bilateral bone defects, 5 x 8 x 3 mm, were created in the maxilla and filled with PCPB + collagen gel (test) or with PCPB only (control) and covered with a collagen membrane. Animals were killed after 2 (n = 3), 4 (n = 3), and 8 weeks (n = 8) for histological and morphometrical evaluations. There were no differences between test and control defects. Both materials showed bone formation directly on the particles by typical osteoblastic seams. The bone area increased with time (2-8 weeks) for both sides, from 16.2% (control) and 19.2% (test) to 42.7 and 43.8%, respectively. The PCPB, whether mixed with collagen gel or not, was resorbed by osteoclasts as well as part of remodeling with the formation of osteons within the particles. Morphometry showed a decrease of PCPB area from 19.4% (control) and 23.8% (test) after 2 weeks to 3.7 and 9.3% after 8 weeks, respectively. Mixing collagen gel and PCPB to facilitate the clinical handling does not influence the bone tissue responses to the material, which exhibited osteoconductive properties and was resorbed with time.

  3. Staged Soft Tissue Reconstruction Following Sarcoma Excision with Anticipated Large Cutaneous Defects: An Oncologically Safe Alternative

    Science.gov (United States)

    Siegel, Geoffrey W; Kuzon, William M.; Hasen, Jill M; Biermann, J. Sybil

    2016-01-01

    Background We hypothesized that select patients undergoing planned soft tissue sarcoma (STS) excision with anticipated skin and soft tissue deficits could be treated with a two stage surgical procedure which would allow some flexibility in coverage options while not significantly increasing local recurrence rate or wound complication rate. Methods A retrospective review was undertaken in a series of consecutive patients with a minimum 2-year follow-up treated by a single orthopedic oncologist and a single reconstructive plastic surgeon who were managed with a staged approach STS excision and reconstruction. Results There were 73 patients identified over a ten-year period that underwent staged STS excision and soft tissue reconstruction. There were 12 (16%) initial positive margins resected to negative final margins, and a variety of coverage procedures performed. Wound complication rate was 21%. Local recurrence rate was 11%. Conclusion Staged STS excision and reconstruction is an acceptable tool in the armamentarium of the orthopedic oncologist for managing major soft tissue deficits without an increase in local recurrence rates. PMID:27528845

  4. Tissue kallikrein-deficient mice display a defect in renal tubular calcium absorption.

    NARCIS (Netherlands)

    Picard, N.; Abel, M. van; Campone, C.; Seiler, M.; Bloch-Faure, M.; Hoenderop, J.G.J.; Loffing, J.; Meneton, P.; Bindels, R.J.M.; Paillard, M.; Alhenc-Gelas, F.; Houillier, P.

    2005-01-01

    Renal tubular calcium (RTCa) transport is one of the main factors that determine serum Ca concentration and urinary Ca excretion. The distal convoluted and connecting tubules reabsorb a significant fraction (10%) of filtered Ca. These tubule segments also synthesize in large abundance tissue

  5. SMRT has tissue-specific isoform profiles that include a form containing one CoRNR box

    International Nuclear Information System (INIS)

    Short, Stephen; Malartre, Marianne; Sharpe, Colin

    2005-01-01

    SMRT acts as a corepressor for a range of transcription factors. The amino-terminal part of the protein includes domains that mainly mediate transcriptional repression whilst the carboxy-terminal part includes domains that interact with nuclear receptors using up to three motifs called CoRNR boxes. The region of the SMRT primary transcript encoding the interaction domains is subject to alternative splicing that varies the inclusion of the third CoRNR box. The profile in mice includes an abundant, novel SMRT isoform that possesses just one CoRNR box. Mouse tissues therefore express SMRT isoforms containing one, two or three CoRNR boxes. In frogs, the SMRT isoform profile is tissue-specific. The mouse also shows distinct profiles generated by differential expression levels of the SMRT transcript isoforms. The formation of multiple SMRT isoforms and their tissue-specific regulation indicates a mechanism, whereby cells can define the repertoire of transcription factors regulated by SMRT

  6. 2-octyl-cyanoacrylate glue for fixation of STSG in genitourinary tissue defects due to Fournier gangrene: a preliminary trial.

    Science.gov (United States)

    Sivrioğlu, Nazan; Irkören, Saime; Ceylan, Ender; Sonel, Ali Murat; Copçu, Eray

    2013-05-01

    In these reported cases, we observed the outcomes of skin take and wound healing using 2-octyl-cyanoacrylate glue, which was used as tissue glue in the reconstruction of complex genital skin loss due to fournier gangrene. Fifteen patients with Fournier's gangrene were treated in this study. After initial surgical debridement, all defects were repaired using STSG. In this method a thin layer of 2-octyl-cyanoacrylate was dripped on the recipient site immediately before graft application. All wounds were followed up postoperatively and observed for evidence of graft take, seroma or hematoma formation, drainage, and infection. Patient and physician satisfaction were also determined. Grafts were completely accepted in all fifteen patients. None of the patients had wound infection, seroma, hematoma, or other complications. Use of 2-octyl-cyanoacrylate glue (Glueseal) for STSG fixation in complex genital skin defects after Fournier gangrene may be an acceptable alternative to conventional surgical closure with a good cosmetic outcome. Further studies are needed to confirm our initial success with this approach.

  7. Role of tissue-engineered artificial tendon in healing of a large Achilles tendon defect model in rabbits.

    Science.gov (United States)

    Moshiri, Ali; Oryan, Ahmad; Meimandi-Parizi, Abdolhamid

    2013-09-01

    Treatment of large Achilles tendon defects is technically demanding. Tissue engineering is an option. We constructed a collagen-based artificial tendon, covered it with a polydioxanon (PDS) sheath, and studied the role of this bioimplant on experimental tendon healing in vivo. A 2-cm tendon gap was created in the left Achilles tendon of rabbits (n = 120). The animals were randomly divided into 3 groups: control (no implant), treated with tridimensional-collagen, and treated with tridimensional-collagen-bidimensional-PDS implants. Each group was divided into 2 subgroups of 60 and 120 days postinjury (DPI). Another 50 pilot animals were used to study the host-implant interaction. Physical activity of the animals was scored and ultrasonographic and bioelectrical characteristics of the injured tendons were investigated weekly. After euthanasia, macro, micro, and nano morphologies and biophysical and biomechanical characteristics of the healing tendons were studied. Treatment improved function of the animals, time dependently. At 60 and 120 DPI, the treated tendons showed significantly higher maximum load, yield, stiffness, stress, and modulus of elasticity compared with controls. The collagen implant induced inflammation and absorbed the migrating fibroblasts in the defect area. By its unique architecture, it aligned the fibroblasts and guided their proliferation and collagen deposition along the stress line of the tendon and resulted in improved collagen density, micro-amp, micro-ohm, water uptake, and delivery of the regenerated tissue. The PDS-sheath covering amplified these characteristics. The implants were gradually absorbed and replaced by a new tendon. Minimum amounts of peritendinous adhesion, muscle atrophy, and fibrosis were observed in the treated groups. Some remnants of the implants were preserved and accepted as a part of the new tendon. The implants were cytocompatible, biocompatible, biodegradable, and effective in tendon healing and regeneration. This

  8. Histomorphometric Analysis of Periodontal Tissue Regeneration by the Use of High Density Polytetrafluoroethylen Membrane in Grade II Furcation Defects of Dogs

    Directory of Open Access Journals (Sweden)

    Raoofi S

    2015-09-01

    Full Text Available Statement of Problem: There are limited histomorphometric studies on biologic efficacy of high density tetrafluoroethylen (d-PTFE membrane. Objectives: To investigate the healing of surgically induced grade II furcation defects in dogs following the use of dense polytetrafluoroethylene as the barrier membrane and to compare the results with the contra lateral control teeth without the application of any membrane. Materials andMethods: Mandibular and maxillary 3rd premolar teeth of 18 young adult male mongrel dogs were used for the experiment. The furcation defects were created during the surgery. 5 weeks later, regenerative surgery was performed. The third premolar teeth were assigned randomly to control and test groups. In the test group, after a full thickness flap reflection, the d-PTFE membrane was placed over furcation defects. In the control group, no membrane was placed over the defect. 37 tissue blocks containing the teeth and surrounding hard and soft tissues were obtained three months post-regenerative surgery. The specimens were demineralized, serially sectioned, mounted and stained with Hematoxylin and Eosin staining technique. From each tissue block, 35-45 sections of 10 μm thickness within 60μm interval captured the entire surgically created defect. The histological images were transferred to computer and then the linear measurement ranges of the defects area, interadicular alveolar bone, epithelial attachment and coronal extension of the new cementum were done. Then, the volume and area of aforementioned parameters were calculated considering the thickness and interval of the sections. To compare the parameters between the control and test teeth, we calculated the amount of each one proportionally to the original amount of defects. Results: The mean interradicular root surface areas of original defects covered with new cementum was 74.46% and 29.59% for the membrane and control defects, respectively (p < 0.0001. Corresponding

  9. Treatment of intrabony defects with guided tissue regeneration in aggressive periodontitis: clinical outcomes at 6 and 12 months.

    Science.gov (United States)

    Rakmanee, Thanasak; Griffiths, Gareth S; Auplish, Gita; Darbar, Ulpee; Petrie, Aviva; Olsen, Irwin; Donos, Nikolaos

    2016-07-01

    The aim of this study was to compare clinical outcomes between guided tissue regeneration (GTR) and access flap (AF) surgery in patients with aggressive periodontitis (AgP). Eighteen AgP patients with similar bilateral intrabony defects were treated in this split-mouth, single-blinded, randomised, controlled clinical trial. All patients presented with ≥3 mm intrabony defects and ≥5 mm periodontal pocket depths (PPD). In each patient, one defect was treated with a polyglycolide membrane according to the GTR principle, whereas the contralateral side was treated with AF. For both sides, a simplified papilla preservation flap was used. At baseline, 6 and 12 months post-surgery, the clinical attachment levels (CAL) and PPD were evaluated. At 6 and 12 months, at the GTR sites, the mean [95 % CI] CAL gain was 1.7 mm [1.1, 2.3] and 1.6 mm [0.9, 2.1], respectively, while the mean [95 % CI] PPD reduction was 2.3 mm [1.9, 2.8] and 2.4 mm [1.9, 2.8], respectively. Similar CAL (1.6 mm [1.0, 2.2] and 2.1 mm [1.4, 2.7]) and PPD (2.0 mm [1.5, 2.4] and 2.5 mm [2.0, 3.0]) outcomes were observed at the control sites at 6 and 12 months, respectively. Notably, at the GTR-treated sites, 13 subjects presented with various degrees of membrane exposure. Both therapies were effective in the treatment of intrabony defects in AgP patients, and no statistically significant differences between them could be demonstrated, possibly as a result of the differing degrees of membrane exposure at the GTR sites. Both periodontal regeneration and conventional periodontal surgery are effective treatments for AgP patients.

  10. Histopathologic analysis of atrial tissue in patients with atrial fibrillation: comparison between patients with atrial septal defect and patients with mitral valvular heart disease.

    Science.gov (United States)

    Kwak, Jae Gun; Seo, Jeong-Wook; Oh, Sam Se; Lee, Sang Yun; Ham, Eui Keun; Kim, Woong-Han; Kim, Soo-Jin; Bae, Eun Jung; Lim, Cheoung; Lee, Chang-Ha; Lee, Cheul

    2014-01-01

    Atrial fibrillation (AF) in adult patients with atrial septal defect (ASD) accompanies an enlarged right atrium (RA) with a less enlarged left atrium (LA), which is the opposite situation in patients with AF and mitral valvular disease. This study was to compare the histopathological change in the atrium of patients with AF of two different etiologies: ASD and mitral disease. Twenty-four patients were enrolled. Group 1 included patients with ASD (8), Group 2 included patients with ASD with AF (6), and Group 3 included patients with mitral disease with AF (10). Preoperative atrial volumes were measured. Atrial tissues were obtained during surgical procedures and stained with periodic acid-Schiff, smooth muscle actin, Sirius red, and Masson's trichrome to detect histopathologic changes compatible with AF. The severity of histopathological changes was represented with "positivity" and "strong positivity" after analyzing digitalized images of the staining. We investigated the relationship between the degree of atrial dilatation and severity of histopathological changes according to the groups and tissues. Group 2 and Group 3 patients showed a tendency toward an enlarged RA volume and enlarged LA volume, respectively, compared with each others. However, in the histopathologic analysis, "positivity" and "strong positivity" showed no significant positive correlations with the degree of atrial volume in special staining. A similar degree of histopathologic changes was observed in both atria in patients with AF (Group 2 and 3) regardless of the degree of dilatation of atrial volume and disease entities. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.

  11. Mammalian tissues defective in nonsense-mediated mRNA decay display highly aberrant splicing patterns

    DEFF Research Database (Denmark)

    Weischenfeldt, Joachim Lütken; Waage, Johannes Eichler; Tian, Geng

    2012-01-01

    ABSTRACT: BACKGROUND: Nonsense-mediated mRNA decay (NMD) affects the outcome of alternative splicing by degrading mRNA isoforms with premature termination codons. Splicing regulators constitute important NMD targets; however, the extent to which loss of NMD causes extensive deregulation...... of alternative splicing has not previously been assayed in a global, unbiased manner. Here, we combine mouse genetics and RNA-seq to provide the first in vivo analysis of the global impact of NMD on splicing patterns in two primary mouse tissues ablated for the NMD factor UPF2. RESULTS: We developed...... importance, the latter events are associated with high intronic conservation. CONCLUSIONS: Our data demonstrate that NMD regulates alternative splicing outcomes through an intricate web of splicing regulators and that its loss leads to the deregulation of a panoply of splicing events, providing novel...

  12. Tissue Engineering Based Therapy for Articular Cartilage Defects - A New Approach

    Directory of Open Access Journals (Sweden)

    Abraham S

    2007-01-01

    Full Text Available Background: Articular cartilage, the load-bearing tissue in diarthrodial joints, when damaged due to trauma could lead to osteoarthritis. At present Autologous Cartilage Implantation is an established method in which patients own chondrocytes are isolated and then implanted after in vitro expansion over the affected area with bovine or porcine collagen matrix. This procedure results in more of Collagen Type I during in vitro expansion, which eventually becomes fibrocartilage. Also it requires growth factors. We have in this study tried growing human Chondrocytes without growth factors using synthetic scaffolds to grow more Collagen Type II Materials and Methods: Human cartilage specimens were harvested through arthroscopy from the non-weight bearing area of the knee joint from 13 patients who underwent surgical procedures of the knee joint after getting their informed consent. The tissues were transported in saline taking 1 hour to laboratory and subjected to digestion with Collagenase type II for 16~18 Hrs. The chondrocyte cells obtained after dissociation were divided into two groups for culture. Gr. I were embedded in a Thermogelation polymer (TGP and Gr. II in basal culture media (DMEM + Ascorbic Acid without using any growth factors. The Group II cells were viable only for 4 weeks and then started degenerating. The TGP-Chondrocytes scaffolds were grown for 16 weeks and the specimens were harvested at 4, 8, 12 and 16-week intervals and their morphology and molecular characteristics were studied by H&E staining, S-100 protein analysis and RT-PCR.Results: Human chondrocytes could be cultured in both TGP (group I and Basal culture media (group II. The Gr. I cells were viable upto the 16th week while the Group II chondrocytes started degenerating after the 4 week. Both the groups were proven positive for S-100 protein, a Chondrocyte specific marker protein; Gr. II specimens after 4 weeks, and Gr. I specimens after 4, 8, 12 and 16 weeks. RT

  13. A reliable method for the treatment of lower third soft tissue defects of the leg: Use of a posterior tibial artery perforator flap

    Directory of Open Access Journals (Sweden)

    Fikret Eren

    2015-12-01

    Full Text Available Management of lower third limb defects is a common challenge for the reconstructive surgeon due to a lack of soft tissue in that anatomic area. Traditionally, lower third of the limb defects were usually reconstructed with free flaps. The evolution of reconstructive surgery enabled thinner and pliable flaps to be harvested for the purpose of minimizing morbidity from muscle inclusion into the flap. With the introduction of perforator flaps, repairing of small and medium size defects of the distal lower third of leg and ankle region is possible with minimal donor site morbidity. Perforator flaps are based on cutaneous, small diameter vessels that arise from a main pedicle that adjacently perforates the fascia to reach the skin. In this article, we present our experience with two cases involving the repair of these defects by using posterior tibial artery perforator flaps. [Hand Microsurg 2015; 4(3.000: 67-70

  14. Bi-allelic Alterations in AEBP1 Lead to Defective Collagen Assembly and Connective Tissue Structure Resulting in a Variant of Ehlers-Danlos Syndrome

    KAUST Repository

    Blackburn, Patrick R.

    2018-03-29

    AEBP1 encodes the aortic carboxypeptidase-like protein (ACLP) that associates with collagens in the extracellular matrix (ECM) and has several roles in development, tissue repair, and fibrosis. ACLP is expressed in bone, the vasculature, and dermal tissues and is involved in fibroblast proliferation and mesenchymal stem cell differentiation into collagen-producing cells. Aebp1 mice have abnormal, delayed wound repair correlating with defects in fibroblast proliferation. In this study, we describe four individuals from three unrelated families that presented with a unique constellation of clinical findings including joint laxity, redundant and hyperextensible skin, poor wound healing with abnormal scarring, osteoporosis, and other features reminiscent of Ehlers-Danlos syndrome (EDS). Analysis of skin biopsies revealed decreased dermal collagen with abnormal collagen fibrils that were ragged in appearance. Exome sequencing revealed compound heterozygous variants in AEBP1 (c.1470delC [p.Asn490_Met495delins(40)] and c.1743C>A [p.Cys581]) in the first individual, a homozygous variant (c.1320_1326del [p.Arg440Serfs3]) in the second individual, and a homozygous splice site variant (c.1630+1G>A) in two siblings from the third family. We show that ACLP enhances collagen polymerization and binds to several fibrillar collagens via its discoidin domain. These studies support the conclusion that biallelic pathogenic variants in AEBP1 are the cause of this autosomal-recessive EDS subtype.

  15. Free tissue transfer versus pedicled flap reconstruction of head and neck malignancy defects.

    LENUS (Irish Health Repository)

    O'Neill, J P

    2012-02-01

    BACKGROUND: With the advent of microsurgery the pedicled flap is considered by many to be an outdated surgical option. AIMS: To explore the relationship between flap survival and pre-morbid risk factors, conduct a comparative analysis of flap and systemic morbidities and complete a cosmesis and functionality assessment for oral and oropharyngeal reconstruction patients. METHODS: 114 patients, over a 13-year period, who had a one-stage reconstructive procedure employing the pectoralis major myocutaneous flap (PMMF) or radial forearm-free flap (RFFF). RESULTS: Variables, including age, smoking and radiation exposure were not statistically significant predictors of flap survival probability. Atelectasis was a significant post-op finding of RFFF patients. Flap dehiscence of >50% was a significant morbidity of PMMF. No statistical difference in cosmetic deformity, diet and socialisation was noted. CONCLUSIONS: Pectoralis major myocutaneous flap remains an enduring and safe flap; however, the RFFF has markedly improved speech performance over the PMMF.

  16. Elevation of sulfatides in ovarian cancer: An integrated transcriptomic and lipidomic analysis including tissue-imaging mass spectrometry

    Directory of Open Access Journals (Sweden)

    McDonald John F

    2010-07-01

    Full Text Available Abstract Background Sulfatides (ST are a category of sulfated galactosylceramides (GalCer that are elevated in many types of cancer including, possibly, ovarian cancer. Previous evidence for elevation of ST in ovarian cancer was based on a colorimetric reagent that does not provide structural details and can also react with other lipids. Therefore, this study utilized mass spectrometry for a structure-specific and quantitative analysis of the types, amounts, and tissue localization of ST in ovarian cancer, and combined these findings with analysis of mRNAs for the relevant enzymes of ST metabolism to explore possible mechanisms. Results Analysis of 12 ovarian tissues graded as histologically normal or having epithelial ovarian tumors by liquid chromatography electrospray ionization-tandem mass spectrometry (LC ESI-MS/MS established that most tumor-bearing tissues have higher amounts of ST. Because ovarian cancer tissues are comprised of many different cell types, histological tissue slices were analyzed by matrix-assisted laser desorption ionization-tissue-imaging MS (MALDI-TIMS. The regions where ST were detected by MALDI-TIMS overlapped with the ovarian epithelial carcinoma as identified by H & E staining and histological scoring. Furthermore, the structures for the most prevalent species observed via MALDI-TIMS (d18:1/C16:0-, d18:1/C24:1- and d18:1/C24:0-ST were confirmed by MALDI-TIMS/MS, whereas, a neighboring ion(m/z 885.6 that was not tumor specific was identified as a phosphatidylinositol. Microarray analysis of mRNAs collected using laser capture microdissection revealed that expression of GalCer synthase and Gal3ST1 (3'-phosphoadenosine-5'-phosphosulfate:GalCer sulfotransferase were approximately 11- and 3.5-fold higher, respectively, in the ovarian epithelial carcinoma cells versus normal ovarian stromal tissue, and they were 5- and 2.3-fold higher in comparison with normal surface ovarian epithelial cells, which is a likely

  17. A stereotaxic, population-averaged T1w ovine brain atlas including cerebral morphology and tissue volumes

    Directory of Open Access Journals (Sweden)

    Björn eNitzsche

    2015-06-01

    Full Text Available Standard stereotaxic reference systems play a key role in human brain studies. Stereotaxic coordinate systems have also been developed for experimental animals including non-human primates, dogs and rodents. However, they are lacking for other species being relevant in experimental neuroscience including sheep. Here, we present a spatial, unbiased ovine brain template with tissue probability maps (TPM that offer a detailed stereotaxic reference frame for anatomical features and localization of brain areas, thereby enabling inter-individual and cross-study comparability. Three-dimensional data sets from healthy adult Merino sheep (Ovis orientalis aries, 12 ewes and 26 neutered rams were acquired on a 1.5T Philips MRI using a T1w sequence. Data were averaged by linear and non-linear registration algorithms. Moreover, animals were subjected to detailed brain volume analysis including examinations with respect to body weight, age and sex. The created T1w brain template provides an appropriate population-averaged ovine brain anatomy in a spatial standard coordinate system. Additionally, TPM for gray (GM and white (WM matter as well as cerebrospinal fluid (CSF classification enabled automatic prior-based tissue segmentation using statistical parametric mapping (SPM. Overall, a positive correlation of GM volume and body weight explained about 15% of the variance of GM while a positive correlation between WM and age was found. Absolute tissue volume differences were not detected, indeed ewes showed significantly more GM per bodyweight as compared to neutered rams. The created framework including spatial brain template and TPM represent a useful tool for unbiased automatic image preprocessing and morphological characterization in sheep. Therefore, the reported results may serve as a starting point for further experimental and/or translational research aiming at in vivo analysis in this species.

  18. The influence of a biomaterial on the closure of a marginal hard tissue defect adjacent to implants. An experimental study in the dog.

    Science.gov (United States)

    Botticelli, Daniele; Berglundh, Tord; Lindhe, Jan

    2004-06-01

    The present experiment was performed to determine the influence of Bio-Oss on hard tissue formation at sites that, following implant installation, presented a 1-1.25 mm wide marginal defect. Four Labrador dogs were used. The premolars and first molars on both sides of the mandible were extracted. After 3 months, mucoperiosteal flaps were elevated and three experimental sites were prepared for implant installation in each side of the mandible. A step drill was used to widen the marginal 5 mm of the canal. Thus, following the placement of the implant (3.3 x 10 mm, SLA surface, Straumann AG, Waldenburg, Switzerland) a circumferential gap, about 1-1.25 wide and 5 mm deep, remained lateral to the titanium rod. The test sites in the left side of the mandible were first filled with a deproteinized cancellous bone mineral (Bio-Oss). The defect sites in the right side of the mandible (control sites) were left for spontaneous healing. A resorbable barrier membrane (Bio-Gide) was placed to cover the implant and the bone tissue in two sites of each quadrant, while the third site was left without membrane placement. The flaps were repositioned to cover all defect sites and were sutured. After 4 months of healing, block biopsies of each implant site were dissected and processed for ground sectioning. It was demonstrated that at 4 months, all types of defects were filled with newly formed bone and that the biomaterial placed in the marginal defect in conjunction with implant installation during healing became incorporated in the newly formed bone tissue. A high degree of contact was established between the Bio-Oss particles and the newly formed bone. Bio-Oss became integrated with the newly formed bone. In the model used, Bio-Oss did not enhance the process of bone formation and defect closure.

  19. Coagulation defects.

    Science.gov (United States)

    Soliman, Doreen E; Broadman, Lynn M

    2006-09-01

    The present understanding of the coagulation process emphasizes the final common pathway and the proteolytic systems that result in the degradation of formed clots and the prevention of unwanted clot formations, as well as a variety of defense systems that include tissue repair, autoimmune processes, arteriosclerosis, tumor growth, the spread of metastases, and defense systems against micro-organisms. This article discusses diagnosis and management of some of the most common bleeding disorders. The goals are to provide a simple guide on how best to manage patients afflicted with congenital or acquired clotting abnormalities during the perioperative period, present a brief overview of the methods of testing and monitoring the coagulation defects, and discuss the appropriate pharmacologic or blood component therapies for each disease.

  20. Comparison of enamel matrix derivative (Emdogain) and subepithelial connective tissue graft for root coverage in patients with multiple gingival recession defects: A randomized controlled clinical study.

    Science.gov (United States)

    Alexiou, Angeliki; Vouros, Ioannis; Menexes, Georgios; Konstantinidis, Antonis

    2017-01-01

    The purpose of the present study was to compare the clinical efficiency of enamel matrix derivative (EMD) placed under a coronally advanced flap (CAF; test group), to a connective tissue graft (CTG) placed under a CAF (control group), in patients with multiple recession defects. Twelve patients with multiple Miller's Class I or II gingival recessions in contralateral quadrants of the maxilla were selected. The primary outcome variable was the change in depth of the buccal recession (REC), at 6 months (T6) after surgery. The secondary outcome parameters included the clinical attachment level (CAL), the probing pocket depth (PPD), and the width of keratinized gingiva (WKT) apical to the recession. Recession defects were randomly divided to the test or control group by using a computer-generated randomization list. Data were analyzed within the frame of Mixed Linear Models with the ANOVA method. There were no statistically significantly differences observed between test and control groups in regards with the depth of buccal recession with a mean REC of 1.82 mm (CTG) and 1.72 mm (EMD) respectively. Similarly the mean PPD value was 1.3 mm for both groups at T6, while the respective value for CAL was 1.7 mm (EMD) and 1.8 mm (CTG). Statistically significant differences were observed only for the WKT, which were 3.0 mm and 3.6 mm for the test and control groups respectively (P < .001) at T6. The use of EMD in conjunction with a CAF resulted in similar results as compared to the CTG plus CAF.

  1. Sutural expansion osteogenesis for management of the bony-tissue defect in cleft palate repair: experimental studies in dogs.

    Science.gov (United States)

    Liu, C; Song, R; Song, Y

    2000-05-01

    A series of experimental studies on sutural expansion osteogenesis for management of the bony-tissue defect in cleft palate repair was performed between 1995 and 1997. Forty-five young dogs in weaning were used in four experiments that were divided into two parts. Part I probed the possibility of closing the surgically constructed hard palate cleft not only with mucoperiosteum but also with bony tissue by the technique of sutural expansion of lateral palatine sutures. Part II explored the possibility of pushing the palatine bone posteriorly and advancing the maxillary segment anteriorly by transverse palatine suture expansion. In Part I, a ring-shaped suture expander made of nickel-titanium shape memory alloy was used to expand the lateral suture of palatine bones. Expansion forces of 200 G, 360 G, and 480 G were used for the first experiment. A force of 360 G was chosen for two other experiments; this force is equivalent to the distraction rate of 0.5 mm per day of a jackscrew device. The ring-shaped suture expander was opened and its two feet were fixed in the medial sides of residual horizontal plates of the palatine bones immediately after a hard palate cleft was constructed surgically under endotracheal general anesthesia. At the eighth postoperative day, under the traction of 360 G, the two sides of the 8-mm-wide hard palate cleft were brought into contact with each other, and 8 or 9 days later the closed palatal cleft had healed completely with mucosal tissue. This experiment was repeated twice and yielded the same results. Sutural expansion osteogenesis was evaluated physically, fluorescently, histologically, and ultrastructurally to examine the deposition of the regenerated bone in the suture areas. Additionally, the influence of sutural expansion osteogenesis of the palatal bones on other facial bones was also studied cephalometrically. In Part II, a bow-shaped suture expander made of nickel-titanium shape memory alloy was applied to expand either the

  2. Comparative study on the role of gelatin, chitosan and their combination as tissue engineered scaffolds on healing and regeneration of critical sized bone defects: an in vivo study.

    Science.gov (United States)

    Oryan, Ahmad; Alidadi, Soodeh; Bigham-Sadegh, Amin; Moshiri, Ali

    2016-10-01

    Gelatin and chitosan are natural polymers that have extensively been used in tissue engineering applications. The present study aimed to evaluate the effectiveness of chitosan and gelatin or combination of the two biopolymers (chitosan-gelatin) as bone scaffold on bone regeneration process in an experimentally induced critical sized radial bone defect model in rats. Fifty radial bone defects were bilaterally created in 25 Wistar rats. The defects were randomly filled with chitosan, gelatin and chitosan-gelatin and autograft or left empty without any treatment (n = 10 in each group). The animals were examined by radiology and clinical evaluation before euthanasia. After 8 weeks, the rats were euthanized and their harvested healing bone samples were evaluated by radiology, CT-scan, biomechanical testing, gross pathology, histopathology, histomorphometry and scanning electron microscopy. Gelatin was biocompatible and biodegradable in vivo and showed superior biodegradation and biocompatibility when compared with chitosan and chitosan-gelatin scaffolds. Implantation of both the gelatin and chitosan-gelatin scaffolds in bone defects significantly increased new bone formation and mechanical properties compared with the untreated defects (P gelatin and chitosan considerably increased structural and functional properties of the healing bones when compared to chitosan scaffold (P gelatin and gelatin-chitosan groups in these regards (P > 0.05). In conclusion, application of the gelatin alone or its combination with chitosan had beneficial effects on bone regeneration and could be considered as good options for bone tissue engineering strategies. However, chitosan alone was not able to promote considerable new bone formation in the experimentally induced critical-size radial bone defects.

  3. Adipose stem cell tissue-engineered construct used to treat large anterior mandibular defect: a case report and review of the clinical application of good manufacturing practice-level adipose stem cells for bone regeneration.

    Science.gov (United States)

    Sándor, George K; Tuovinen, Veikko J; Wolff, Jan; Patrikoski, Mimmi; Jokinen, Jari; Nieminen, Elina; Mannerström, Bettina; Lappalainen, Olli-Pekka; Seppänen, Riitta; Miettinen, Susanna

    2013-05-01

    Large mandibular resection defects historically have been treated using autogenous bone grafts and reconstruction plates. However, a major drawback of large autogenous bone grafts is donor-site morbidity. This report describes the replacement of a 10-cm anterior mandibular ameloblastoma resection defect, reproducing the original anatomy of the chin, using a tissue-engineered construct consisting of β-tricalcium phosphate (β-TCP) granules, recombinant human bone morphogenetic protein-2 (BMP-2), and Good Manufacturing Practice-level autologous adipose stem cells (ASCs). Unlike prior reports, 1-step in situ bone formation was used without the need for an ectopic bone-formation step. The reconstructed defect was rehabilitated with a dental implant-supported overdenture. An additive manufactured medical skull model was used preoperatively to guide the prebending of patient-specific hardware, including a reconstruction plate and titanium mesh. A subcutaneous adipose tissue sample was harvested from the anterior abdominal wall of the patient before resection and simultaneous reconstruction of the parasymphysis. ASCs were isolated and expanded ex vivo over the next 3 weeks. The cell surface marker expression profile of ASCs was similar to previously reported results and ASCs were analyzed for osteogenic differentiation potential in vitro. The expanded cells were seeded onto a scaffold consisting of β-TCP and BMP-2 and the cell viability was evaluated. The construct was implanted into the parasymphyseal defect. Ten months after reconstruction, dental implants were inserted into the grafted site, allowing harvesting of bone cores. Histologic examination and in vitro analysis of cell viability and cell surface markers were performed and prosthodontic rehabilitation was completed. ASCs in combination with β-TCP and BMP-2 offer a promising construct for the treatment of large, challenging mandibular defects without the need for ectopic bone formation and allowing

  4. Deep tissue biopsy vs. superficial swab culture, including microbial loading determination, in the microbiological assessment of Skin and Soft Tissue Infections (SSTIs).

    Science.gov (United States)

    Esposito, Silvano; De Simone, Giuseppe; Gioia, Renato; Noviello, Silvana; Pagliara, Domenico; Campitiello, Nicola; Rubino, Corrado; Lo Pardo, Dante; Boccia, Giovanni; De Caro, Francesco; Ascione, Tiziana

    2017-06-01

    Thirty-two patients affected by SSTIs including DFIs were enrolled between 2013 and 2014. Superficial swab was obtained before and after cleansing with sterile saline, and after ultrasonic debridement; deep tissue biopsy was obtained from ulcer base. Samples were diluted with 1 mL of saline, serial 10-fold dilutions to 10 -6 were made and 50 μL of each dilution was plated onto appropriate media. Bacteria were identified by Vitek II system. Microbial load was expressed as CFU/mL. Statistical analysis was performed by χ2. Incidence of Gram positives was higher than Gram negatives (S. aureus and P. aeruginosa being the most frequent); concordance (same bacteria isolated before and after debridement) never exceeded 60%. Ultrasonic debridement significantly reduced bacterial load or even suppressed bacterial growth. While reliability of superficial swab is poor for microbiological diagnosis of SSTIs, swabbing after ultrasonic debridement and biopsy of the ulcer base may be equally reliable.

  5. Effect of a Connective Tissue Graft in Combination With a Single Flap Approach in the Regenerative Treatment of Intraosseous Defects [Formula: see text].

    Science.gov (United States)

    Trombelli, Leonardo; Simonelli, Anna; Minenna, Luigi; Rasperini, Giulio; Farina, Roberto

    2017-04-01

    In the attempt to limit the post-surgery increase in buccal gingival recession (bREC), effect of a connective tissue graft (CTG) when combined with a buccal single flap approach (SFA) in the regenerative treatment of intraosseous defects is evaluated. Data related to 30 patients with an intraosseous defect treated with a buccal SFA with (SFA+CTG group; n = 15) or without (SFA group; n = 15) placement of a CTG and regenerative treatment were retrospectively derived at three clinical centers. bREC and probing parameters were assessed at presurgery and 6 months post-surgery. In addition to a significant attachment gain and probing depth reduction, adjunctive use of a CTG to a buccal SFA in the regenerative treatment of periodontal intraosseous defects associated with a buccal bone dehiscence resulted in a limited post-surgery bREC, a lower prevalence of defects with a clinically detectable apical displacement of the gingival margin, and an increase in gingival width and thickness. Adjunctive use of a CTG in the regenerative treatment of intraosseous defects associated with buccal bone dehiscence accessed by buccal SFA may support the stability of the gingival profile.

  6. Low-level laser therapy as an adjunct to connective tissue graft procedure in the treatment of gingival recession defects: A systematic review and meta-analysis.

    Science.gov (United States)

    Akram, Zohaib; Vohra, Fahim; Javed, Fawad

    2018-03-26

    The aim of this study was to systematically evaluate the effectiveness of low level laser therapy (LLLT) as an adjunct to connective tissue graft (CTG) procedure for the treatment of gingival recession (GR). The addressed PICO question was; "In patients with Miller Class I or II recession defects (Population), what is the effect of LLLT as adjunct to CTG (Intervention) in comparison to CTG alone (Comparison) on gingival recession depth (Outcome)" Electronic databases were searched up to December 2017. Primary outcomes included gingival recession depth (GRD), whereas secondary outcomes were width of keratinized tissue (WKT) and relative clinical attachment level gain (RCAL). The weighted mean differences (WMD) of outcomes and 95% confidence intervals (CI) for each variable were calculated using random effect model. Four randomized clinical studies were included. Two studies showed significantly greater improvements with LLLT whereas, 2 studies showed comparable outcomes between LLLT and CTG group. Considering the effects of adjunctive LLLT as compared to CTG, a high degree of heterogeneity for GRD (Q value = 9.40, P = .02, I 2 =68.11%) and WKT ((Q value = 16.04, P = .001, I 2 =81.31%) was noticed among both the groups. Meta-analysis showed a statistically significant GRD (WMD= -0.61, 95% CI= -1.23 to 0.004, P = .05) for LLLT + CTG treatment versus CTG alone only. LLLT improves clinical and patient-centered outcomes of CTG procedures for the treatment of GR remains debatable. However, due to the small number of included studies and high heterogeneity in the laser parameters, precautions must be exercised when interpreting the results of the present systematic review. Gingival recessions in dentistry are of major esthetic concern. Minimal gingival recessions can be treated by flap operations, but the predictability and stability of the outcomes is debatable. In the present review, low level laser therapy (LLLT) adjunct to connective tissue

  7. Repair of deep tissue defects in the posterior talocrural region using a superficial temporal fascia free flap plus thin split-skin grafting in extensively burned patients

    Science.gov (United States)

    Yang, Xuekang; Zhao, Hui; Liu, Mengdong; Zhang, Yue; Chen, Qiaohua; Li, Zhiqiang; Han, Juntao; Hu, Dahai

    2018-01-01

    Abstract The aim of this study was to describe the scheme, surgical procedures, and clinical outcomes for the early repair of deep wounds of the posterior talocrural region in extensively burned patients with a method combining a superficial temporal fascia free flap with thin split-skin grafting. From January 2013 to February 2016, 9 extensively burned patients with deep tissue defects of the posterior talocrural region were treated in our department (2 patients had bilateral deep tissue defects of the posterior talocrural region). All 11 wounds were repaired using a superficial temporal fascia free flap and thin split-skin grafting. After the operation, survival of the fascia flaps and grafted skin was observed, and the appearance and functional recovery of the grafts were evaluated. Follow-up information was reviewed, and complications were documented. All 11 fascia flaps survived completely. Two cases of partial skin necrosis healed after the second application of skin grafts. The appearance and function of recipient sites were well restored in all patients over a follow-up period of 5 to 14 months. Deep tissue defects of the posterior talocrural region can be effectively repaired with our method combining a superficial temporal fascia free flap with thin split-skin grafting. This method offers the advantages of a good appearance, strong resistance to infection, minimal damage at the donor site, short course of disease, and good prognosis. PMID:29504968

  8. Repair of a soft tissue defect of medial malleolus with cross-leg bridge free transfer of anterolateral thigh muscle flap: a case report

    Directory of Open Access Journals (Sweden)

    ZHANG Gong-lin

    2012-11-01

    Full Text Available 【Abstract】A 38-year-old man sustained a traffic accident injury to his right medial malleolus and leg. It was an open fracture of the right tibia and fibula accompanied by a large soft tissue defect of the right medial malleolus sized 12 cm×4 cm. Doppler examination revealed that the tibialis posterior vessel was occluded due to thrombosis. The anterior tibial artery was patent. Three weeks after injury, the left anterolateral thigh muscle flap was harvested and transplanted to the right medial malleolus defect area for repair of the soft tissue defect, and an end-to-side anasto-mosis was performed between the posterior tibial vessel of the contralateral leg and the muscle flap’s vascular pedicle. A split thickness free skin graft was used to cover the muscle flap and around the flap’s vascular pedicle. The vascular pedicle was cut off after 28 days and the muscle flap sur-vived completely. After 3-year follow-up postoperatively, the right tibia and fibula fractures were confirmed healing radiologically. The posterior tibial artery of contralateral leg was patent by clinical and Doppler examinations. This tech-nique can be used to preserve the flow and patency of re-cipient arteries. Key words: Surgical flaps; Soft tissue injuries; Leg injuries; Wound healing

  9. Loss of Drosophila A-type lamin C initially causes tendon abnormality including disintegration of cytoskeleton and nuclear lamina in muscular defects.

    Science.gov (United States)

    Uchino, Ryo; Nonaka, Yu-Ki; Horigome, Tuneyoshi; Sugiyama, Shin; Furukawa, Kazuhiro

    2013-01-01

    Lamins are the major components of nuclear envelope architecture, being required for both the structural and informational roles of the nuclei. Mutations of lamins cause a spectrum of diseases in humans, including muscular dystrophy. We report here that the loss of the A-type lamin gene, lamin C in Drosophila resulted in pupal metamorphic lethality caused by tendon defects, matching the characteristics of human A-type lamin revealed by Emery-Dreifuss muscular dystrophy (EDMD). In tendon cells lacking lamin C activity, overall cell morphology was affected and organization of the spectraplakin family cytoskeletal protein Shortstop which is prominently expressed in tendon cells gradually disintegrated, notably around the nucleus and in a manner correlating well with the degradation of musculature. Furthermore, lamin C null mutants were efficiently rescued by restoring lamin C expression to shortstop-expressing cells, which include tendon cells but exclude skeletal muscle cells. Thus the critical function of A-type lamin C proteins in Drosophila musculature is to maintain proper function and morphology of tendon cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Prevention of dental anomalies in children by prosthetics defects hard tooth tissues and dentitions: the need to possibilities

    Directory of Open Access Journals (Sweden)

    Suetenkov D.Ye.

    2011-03-01

    Full Text Available This article presents the possibility of restore the function and anatomy of the tooth and replacement of defects of dentition by prosthesis in children under the removable bite as a method of prevention of dentoalveolar anomalies. Identified the need for prosthetic treatment of children and the willingness of dentists as primary health care professional to address the problems identified. A clinical analysis of complex treatment of defects in the teeth with fixed restorations

  11. Bone regeneration in 3D printing bioactive ceramic scaffolds with improved tissue/material interface pore architecture in thin-wall bone defect.

    Science.gov (United States)

    Shao, Huifeng; Ke, Xiurong; Liu, An; Sun, Miao; He, Yong; Yang, Xianyan; Fu, Jianzhong; Liu, Yanming; Zhang, Lei; Yang, Guojing; Xu, Sanzhong; Gou, Zhongru

    2017-04-12

    Three-dimensional (3D) printing bioactive ceramics have demonstrated alternative approaches to bone tissue repair, but an optimized materials system for improving the recruitment of host osteogenic cells into the bone defect and enhancing targeted repair of the thin-wall craniomaxillofacial defects remains elusive. Herein we systematically evaluated the role of side-wall pore architecture in the direct-ink-writing bioceramic scaffolds on mechanical properties and osteogenic capacity in rabbit calvarial defects. The pure calcium silicate (CSi) and dilute Mg-doped CSi (CSi-Mg6) scaffolds with different layer thickness and macropore sizes were prepared by varying the layer deposition mode from single-layer printing (SLP) to double-layer printing (DLP) and then by undergoing one-, or two-step sintering. It was found that the dilute Mg doping and/or two-step sintering schedule was especially beneficial for improving the compressive strength (∼25-104 MPa) and flexural strength (∼6-18 MPa) of the Ca-silicate scaffolds. The histological analysis for the calvarial bone specimens in vivo revealed that the SLP scaffolds had a high osteoconduction at the early stage (4 weeks) but the DLP scaffolds displayed a higher osteogenic capacity for a long time stage (8-12 weeks). Although the DLP CSi scaffolds displayed somewhat higher osteogenic capacity at 8 and 12 weeks, the DLP CSi-Mg6 scaffolds with excellent fracture resistance also showed appreciable new bone tissue ingrowth. These findings demonstrate that the side-wall pore architecture in 3D printed bioceramic scaffolds is required to optimize for bone repair in calvarial bone defects, and especially the Mg doping wollastontie is promising for 3D printing thin-wall porous scaffolds for craniomaxillofacial bone defect treatment.

  12. Non-thermodynamic approach to including bombardment-induced post-cascade redistribution of point defects in dynamic Monte Carlo code

    CERN Document Server

    Ignatova, V A; Katardjiev, I V

    2003-01-01

    The redistribution of the elements as a result of atomic relocations produced by the ions and the recoils due to the ballistic and transport processes is investigated by making use of a dynamic Monte Carlo code. Phenomena, such as radiation-enhanced diffusion (RED) and bombardment-induced segregation (BIS) triggered by the ion bombardment may also contribute to the migration of atoms within the target. In order to include both RED and BIS in the code, we suggest an approach which is considered as an extension of the binary collision approximation, i.e. it takes place 'simultaneously' with the cascade and acts as a correction to the particle redistribution for low energies. Both RED and BIS models are based on the common approach to treat the transport processes as a result of a random migration of point defects (vacancies and interstitials) according to a probability given by a pre-defined Gaussian. The models are tested and the influence of the diffusion and segregation is illustrated in the cases of 12 keV ...

  13. The healing of bony defects by cell-free collagen-based scaffolds compared to stem cell-seeded tissue engineered constructs.

    LENUS (Irish Health Repository)

    Lyons, Frank G

    2010-12-01

    One of the key challenges in tissue engineering is to understand the host response to scaffolds and engineered constructs. We present a study in which two collagen-based scaffolds developed for bone repair: a collagen-glycosaminoglycan (CG) and biomimetic collagen-calcium phosphate (CCP) scaffold, are evaluated in rat cranial defects, both cell-free and when cultured with MSCs prior to implantation. The results demonstrate that both cell-free scaffolds showed excellent healing relative to the empty defect controls and somewhat surprisingly, to the tissue engineered (MSC-seeded) constructs. Immunological analysis of the healing response showed higher M1 macrophage activity in the cell-seeded scaffolds. However, when the M2 macrophage response was analysed, both groups (MSC-seeded and non-seeded scaffolds) showed significant activity of these cells which are associated with an immunomodulatory and tissue remodelling response. Interestingly, the location of this response was confined to the construct periphery, where a capsule had formed, in the MSC-seeded groups as opposed to areas of new bone formation in the non-seeded groups. This suggests that matrix deposited by MSCs during in vitro culture may adversely affect healing by acting as a barrier to macrophage-led remodelling when implanted in vivo. This study thus improves our understanding of host response in bone tissue engineering.

  14. Inhibiting PHD2 in bone marrow mesenchymal stem cells via lentiviral vector-mediated RNA interference facilitates the repair of periodontal tissue defects in SD rats

    Science.gov (United States)

    Chen, Changxing; Li, Houxuan; Jiang, Jun; Zhang, Qian; Yan, Fuhua

    2017-01-01

    Hypoxia-inducible factors (HIFs) play an important role in angiogenesis, and they can activate the expression of several downstream angiogenic factors. HIF-1 is a major transcriptor of HIFs, composed of α and β subunits. Prolyl hydroxylase domain-containing protein 2 (PHD2) is the main catabolic enzyme for HIF-1α, and it can accelerate its degradation under normoxic conditions. PHD2 expression in bone marrow mesenchymal stem cells (BMMSCs) of SD rats was down-regulated under normoxic conditions in this study by utilizing lentiviral vector-mediated RNA interference to promote HIF-1α accumulation, thus enhancing the expression of angiogenic factors. A tissue-engineered compound was constructed using the composite collagen membrane of BMMSCs after PHD2 gene silencing to repair periodontal fenestration defects in SD rats. The results of this study indicated that, after PHD2 gene silencing, the osteogenic differentiation of BMMSCs was enhanced in vitro, the resistance of cells to oxidative stress was also validated in vitro, thereby illustrating the promotion of the repair of artificially constructed periodontal tissue defects in rats. The results of this study provide a reference and guidance for future applications of RNA interference in periodontal tissue engineering and serve as a basis for improving the survival of seed cells in recipient tissues. PMID:29069818

  15. MTO1 mediates tissue specificity of OXPHOS defects via tRNA modification and translation optimization, which can be bypassed by dietary intervention

    Science.gov (United States)

    Tischner, Christin; Hofer, Annette; Wulff, Veronika; Stepek, Joanna; Dumitru, Iulia; Becker, Lore; Haack, Tobias; Kremer, Laura; Datta, Alexandre N.; Sperl, Wolfgang; Floss, Thomas; Wurst, Wolfgang; Chrzanowska-Lightowlers, Zofia; De Angelis, Martin Hrabe; Klopstock, Thomas; Prokisch, Holger; Wenz, Tina

    2015-01-01

    Mitochondrial diseases often exhibit tissue-specific pathologies, but this phenomenon is poorly understood. Here we present regulation of mitochondrial translation by the Mitochondrial Translation Optimization Factor 1, MTO1, as a novel player in this scenario. We demonstrate that MTO1 mediates tRNA modification and controls mitochondrial translation rate in a highly tissue-specific manner associated with tissue-specific OXPHOS defects. Activation of mitochondrial proteases, aberrant translation products, as well as defects in OXPHOS complex assembly observed in MTO1 deficient mice further imply that MTO1 impacts translation fidelity. In our mouse model, MTO1-related OXPHOS deficiency can be bypassed by feeding a ketogenic diet. This therapeutic intervention is independent of the MTO1-mediated tRNA modification and involves balancing of mitochondrial and cellular secondary stress responses. Our results thereby establish mammalian MTO1 as a novel factor in the tissue-specific regulation of OXPHOS and fine tuning of mitochondrial translation accuracy. PMID:25552653

  16. In-situ tissue regeneration through SDF-1α driven cell recruitment and stiffness-mediated bone regeneration in a critical-sized segmental femoral defect.

    Science.gov (United States)

    Cipitria, Amaia; Boettcher, Kathrin; Schoenhals, Sophia; Garske, Daniela S; Schmidt-Bleek, Katharina; Ellinghaus, Agnes; Dienelt, Anke; Peters, Anja; Mehta, Manav; Madl, Christopher M; Huebsch, Nathaniel; Mooney, David J; Duda, Georg N

    2017-09-15

    In-situ tissue regeneration aims to utilize the body's endogenous healing capacity through the recruitment of host stem or progenitor cells to an injury site. Stromal cell-derived factor-1α (SDF-1α) is widely discussed as a potent chemoattractant. Here we use a cell-free biomaterial-based approach to (i) deliver SDF-1α for the recruitment of endogenous bone marrow-derived stromal cells (BMSC) into a critical-sized segmental femoral defect in rats and to (ii) induce hydrogel stiffness-mediated osteogenic differentiation in-vivo. Ionically crosslinked alginate hydrogels with a stiffness optimized for osteogenic differentiation were used. Fast-degrading porogens were incorporated to impart a macroporous architecture that facilitates host cell invasion. Endogenous cell recruitment to the defect site was successfully triggered through the controlled release of SDF-1α. A trend for increased bone volume fraction (BV/TV) and a significantly higher bone mineral density (BMD) were observed for gels loaded with SDF-1α, compared to empty gels at two weeks. A trend was also observed, albeit not statistically significant, towards matrix stiffness influencing BV/TV and BMD at two weeks. However, over a six week time-frame, these effects were insufficient for bone bridging of a segmental femoral defect. While mechanical cues combined with ex-vivo cell encapsulation have been shown to have an effect in the regeneration of less demanding in-vivo models, such as cranial defects of nude rats, they are not sufficient for a SDF-1α mediated in-situ regeneration approach in segmental femoral defects of immunocompetent rats, suggesting that additional osteogenic cues may also be required. Stromal cell-derived factor-1α (SDF-1α) is a chemoattractant used to recruit host cells for tissue regeneration. The concept that matrix stiffness can direct mesenchymal stromal cell (MSC) differentiation into various lineages was described a decade ago using in-vitro experiments. Recently

  17. The scale-up of a tissue engineered porous hydroxyapatite polymer composite scaffold for use in bone repair: an ovine femoral condyle defect study.

    Science.gov (United States)

    Tayton, Edward; Purcell, Matthew; Smith, James O; Lanham, Stuart; Howdle, Steven M; Shakesheff, Kevin M; Goodship, Allen; Blunn, Gordon; Fowler, Darren; Dunlop, Douglas G; Oreffo, Richard O C

    2015-04-01

    The development of an osteogenic bone graft substitute has important practical and cost implications in many branches of medicine where bone regeneration is required. Previous in vitro and small animal (murine) in vivo studies highlighted a porous hydroxyapatite/poly (DL-lactic acid) composite scaffold in combination with skeletal stem cells (SSCs) as a potential bone graft substitute candidate. The aim of the current study was to scale up the bone cell-scaffold construct to large animals and examine the potential for repair of a critical-sized defect via an ovine model. SSC seeded scaffolds (and unseeded scaffold controls) were implanted bilaterally into ovine femoral condyle critical defects for 3 months. A parallel in vitro analysis of ovine SSC seeded scaffolds was also performed. Post mortem mechanical indentation testing showed the bone strengths of the defect sites were 20% (controls) and 11% (SSC seeded scaffolds) those of normal cancellous bone (p scaffolds over the SSC seeded scaffolds (p = 0.14). Histological examination confirmed these findings, with enhanced quality new bone within the control defects. This study highlights important issues and steps to overcome in scale-up and translation of tissue engineered products. The scaffold demonstrated encouraging results as an osteoconductive matrix; however, further work is required with cellular protocols before any human trials. © 2014 Wiley Periodicals, Inc.

  18. The Benefits of Including Clinical Factors in Rectal Normal Tissue Complication Probability Modeling After Radiotherapy for Prostate Cancer

    International Nuclear Information System (INIS)

    Defraene, Gilles; Van den Bergh, Laura; Al-Mamgani, Abrahim; Haustermans, Karin; Heemsbergen, Wilma; Van den Heuvel, Frank; Lebesque, Joos V.

    2012-01-01

    Purpose: To study the impact of clinical predisposing factors on rectal normal tissue complication probability modeling using the updated results of the Dutch prostate dose-escalation trial. Methods and Materials: Toxicity data of 512 patients (conformally treated to 68 Gy [n = 284] and 78 Gy [n = 228]) with complete follow-up at 3 years after radiotherapy were studied. Scored end points were rectal bleeding, high stool frequency, and fecal incontinence. Two traditional dose-based models (Lyman-Kutcher-Burman (LKB) and Relative Seriality (RS) and a logistic model were fitted using a maximum likelihood approach. Furthermore, these model fits were improved by including the most significant clinical factors. The area under the receiver operating characteristic curve (AUC) was used to compare the discriminating ability of all fits. Results: Including clinical factors significantly increased the predictive power of the models for all end points. In the optimal LKB, RS, and logistic models for rectal bleeding and fecal incontinence, the first significant (p = 0.011–0.013) clinical factor was “previous abdominal surgery.” As second significant (p = 0.012–0.016) factor, “cardiac history” was included in all three rectal bleeding fits, whereas including “diabetes” was significant (p = 0.039–0.048) in fecal incontinence modeling but only in the LKB and logistic models. High stool frequency fits only benefitted significantly (p = 0.003–0.006) from the inclusion of the baseline toxicity score. For all models rectal bleeding fits had the highest AUC (0.77) where it was 0.63 and 0.68 for high stool frequency and fecal incontinence, respectively. LKB and logistic model fits resulted in similar values for the volume parameter. The steepness parameter was somewhat higher in the logistic model, also resulting in a slightly lower D 50 . Anal wall DVHs were used for fecal incontinence, whereas anorectal wall dose best described the other two endpoints. Conclusions

  19. Characterization of the Embryogenic Tissue of the Norway Spruce Including a Transition Layer between the Tissue and the Culture Medium by Magnetic Resonance Imaging

    Science.gov (United States)

    Kořínek, R.; Mikulka, J.; Hřib, J.; Hudec, J.; Havel, L.; Bartušek, K.

    2017-02-01

    The paper describes the visualization of the cells (ESEs) and mucilage (ECMSN) in an embryogenic tissue via magnetic resonance imaging (MRI) relaxometry measurement combined with the subsequent multi-parametric segmentation. The computed relaxometry maps T1 and T2 show a thin layer (transition layer) between the culture medium and the embryogenic tissue. The ESEs, mucilage, and transition layer differ in their relaxation times T1 and T2; thus, these times can be used to characterize the individual parts within the embryogenic tissue. The observed mean values of the relaxation times T1 and T2 of the ESEs, mucilage, and transition layer are as follows: 1469 ± 324 and 53 ± 10 ms, 1784 ± 124 and 74 ± 8 ms, 929 ± 164 and 32 ± 4.7 ms, respectively. The multi-parametric segmentation exploiting the T1 and T2 relaxation times as a classifier shows the distribution of the ESEs and mucilage within the embryogenic tissue. The discussed T1 and T2 indicators can be utilized to characterize both the growth-related changes in an embryogenic tissue and the effect of biotic/abiotic stresses, thus potentially becoming a distinctive indicator of the state of any examined embryogenic tissue.

  20. 2-year postoperative evaluation of a patient with a symptomatic full-thickness patellar cartilage defect repaired with particulated juvenile cartilage tissue.

    Science.gov (United States)

    Bonner, Kevin F; Daner, William; Yao, Jian Q

    2010-06-01

    This case report describes the early results of a 36-year-old man who underwent repair of a symptomatic full-thickness patellar cartilage defect with transplanted particulated juvenile articular cartilage. At 2 years postoperatively, the patient has experienced substantial clinical improvement in both pain and function when evaluated with both International Knee Documentation Committee subjective evaluation and Knee Injury and Osteoarthritis Outcome Score outcome measures. Two-year postoperative magnetic resonance imaging demonstrates fill of the defect with repair tissue and near complete resolution of preoperative subchondral bone edema. To the best of the authors' knowledge, this case report is the first to report clinical results of this new technique at 2 years postoperatively.

  1. The pulley suture: A reliable option for closure of selected soft tissue defects under tension- three years experience of a tertiary care hospital.

    Science.gov (United States)

    Saeed, Sadaf; Ahmed, Syed Kamran; Chinoy, Muhammad Amin; Khan, Mansoor Ali

    2015-03-01

    To assess the outcome of closure of soft tissue defects through pulley suture in different clinical situations. The descriptive chart review was conducted at The Indus Hospital, Karachi, and comprised data from May 2008 to November 2011. A detailed questionnaire was developed to address variables of interest. All patients with less than three months of follow-up or inadequate information were excluded. The data was collected through Health Management Information System. Data was entered and analysed by SPSS 16. There were 259 patients with 289 wounds in the study. The mean age was 29.2±11.9 years. At follow-up of two weeks, there was wound dehiscence in 2.07%, infection in 0.69% and partial flap necrosis in 1.03% patients. At 12 weeks, hypertrophic scar was reported in 2.07% and stretched scar in 0.3% patients. Acute pain was not reported in the first week of surgery. Type of wound was found to have significant association with complications (p valuepulley suture can lead to primary closure of selected soft tissue defects under moderate tension. The technique, however, needs to be utilised by surgeons experienced in soft tissue reconstruction.

  2. Treatment of a large periradicular defect using guided tissue regeneration: A case report of 2 years follow-up and surgical re-entry

    Directory of Open Access Journals (Sweden)

    Abhijit Ningappa Gurav

    2015-01-01

    Full Text Available Periradicular (PR bone defects are common sequelae of chronic endodontic lesions. Sometimes, conventional root canal therapy is not adequate for complete resolution of the lesion. PR surgeries may be warranted in such selected cases. PR surgery provides a ready access for the removal of pathologic tissue from the periapical region, assisting in healing. Recently, the regeneration of the destroyed PR tissues has gained more attention rather than repair. In order to promote regeneration after apical surgery, the principle of guided tissue regeneration (GTR has proved to be useful. This case presents the management of a large PR lesion in a 42-year-old male subject. The PR lesion associated with 21, 11 and 12 was treated using GTR membrane, fixated with titanium minipins. The case was followed up for 2 years radiographically, and a surgical re-entry confirmed the re-establishment of the lost labial plate. Thus, the principle of GTR may immensely improve the clinical outcome and prognosis of an endodontically involved tooth with a large PR defect.

  3. Repair of a large soft tissue defect in the leg with cross-leg bridge free transfer of a latissimus dorsi myocutaneous flap: a case report

    Directory of Open Access Journals (Sweden)

    ZHANG Gong-lin

    2012-12-01

    Full Text Available 【Abstract】A 48-year-old man sustained a traffic accident injury to his left leg. It was an open fracture of the left tibia and fibula accompanied by a large soft tissue de-fect (27 cm×7 cm. Doppler examination revealed the poste-rior tibial artery was occluded due to thrombosis. Three weeks after injury, the latissimus dors myocutaneous flap was elevated with a T-shaped vascular pedicle and was in-terposed between the two vascular ends of the posterior tibial vessel of the contralateral leg. Two end to end anasto-moses were performed between the two vascular ends of the posterior tibial vessel of the contralateral leg and the latissimus dors myocutaneous flap’s T-shaped vascular pedicle. The latissimus dorsi myocutaneous flap was used for repair of a large soft tissue defect of the left leg. The vascular pedicle was cut off after 28 days and the flap sur-vived completely. After 3-years’ follow-up postoperatively, a good contour was confirmed at the recipient area. The right tibia and fibula fractures were confirmed healing radiologically. The posterior tibial artery of contralateral leg was demonstrated patent by clinical and Doppler examinations. Key words: Surgical flaps; Leg injuries; Soft tissue injuries; Wound healing

  4. PTH/SDF-1α cotherapy induces CD90+CD34− stromal cells migration and promotes tissue regeneration in a rat periodontal defect model

    Science.gov (United States)

    Wang, Fang; Du, Lingqian; Ge, Shaohua

    2016-01-01

    Stromal cell-derived factor-1α (SDF-1α) is a key stem cell homing factor that is crucial for recruitment of stem cells to many diseased organs. However, the therapeutic activity of SDF-1α is potentially limited by N-terminal cleavage at position-2 proline by a cell surface protein CD26/dipeptidyl peptidase-IV (DPP-IV). Parathyroid hormone (PTH) is a DPP-IV inhibitor and has been suggested as a promising agent for periodontal tissue repair. The purpose of this study was to explore the effects of a cell-free system comprising SDF-1α and scaffold plus PTH systemic application on periodontal tissue regeneration in vivo. The results showed that PTH/SDF-1α cotherapy improved the quantity of regenerated bone and resulted in better organization of ligament interface. We further investigated the possible mechanisms, and found that PTH/SDF-1α cotherapy enhanced CD90+CD34− stromal cells migration in vivo, increased the number of CXCR4 + cells in periodontal defects, induced early bone osteoclastogenesis and enhanced the expression of runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP) and collagen I (Col I) in newly formed bone tissue. In conclusion, this cell-free tissue engineering system with local administration of SDF-1α and systemic application of PTH could be employed to induce CD90+CD34− stromal cells recruitment and promote periodontal tissue regeneration. PMID:27480134

  5. Tissue-Specific Methylation of Long Interspersed Nucleotide Element-1 of Homo Sapiens (L1Hs) During Human Embryogenesis and Roles in Neural Tube Defects.

    Science.gov (United States)

    Wang, L; Chang, S; Guan, J; Shangguan, S; Lu, X; Wang, Z; Wu, L; Zou, J; Zhao, H; Bao, Y; Qiu, Z; Niu, B; Zhang, T

    2015-01-01

    Epigenetic regulation of long interspersed nucleotide element-1 (LINE-1) retrotransposition events plays crucial roles during early development. Previously we showed that LINE-1 hypomethylation in neuronal tissues is associated with pathogenesis of neural tube defect (NTD). Herein, we further evaluated LINE-1 Homo sapiens (L1Hs) methylation in tissues derived from three germ layers of stillborn NTD fetuses, to define patterns of tissue specific methylation and site-specific hypomethylation at CpG sites within an L1Hs promoter region. Stable, tissue-specific L1Hs methylation patterns throughout three germ layer lineages of the fetus, placenta, and maternal peripheral blood were observed. Samples from maternal peripheral blood exhibited the highest level of L1Hs methylation (64.95%) and that from placenta showed the lowest (26.82%). Between samples from NTDs and controls, decrease in L1Hs methylation was only significant in NTD-affected brain tissue at 7.35%, especially in females (8.98%). L1Hs hypomethylation in NTDs was also associated with a significant increase in expression level of an L1Hs-encoded transcript in females (r = -0.846, p = 0.004). This could be due to genomic DNA instability and alternation in chromatins accessibility resulted from abnormal L1Hs hypomethylation, as showed in this study with HCT-15 cells treated with methylation inhibitor 5-Aza.

  6. Development and application of a rapid rehabilitation system for reconstruction of maxillofacial soft-tissue defects related to war and traumatic injuries.

    Science.gov (United States)

    Bai, Shi-Zhu; Feng, Zhi-Hong; Gao, Rui; Dong, Yan; Bi, Yun-Peng; Wu, Guo-Feng; Chen, Xi

    2014-01-01

    The application of a maxillofacial prosthesis is an alternative to surgery in functional-aesthetic facial reconstruction. Computer aided design/computer aided manufacturing has opened up a new approach to the fabrication of maxillofacial prostheses. An intelligentized rapid simulative design and manufacturing system for prostheses was developed to facilitate the prosthesis fabrication procedure. The rapid simulation design and rapid fabrication system for maxillofacial prostheses consists of three components: digital impression, intelligentized prosthesis design, and rapid manufacturing. The patients' maxillofacial digital impressions were taken with a structured-light 3D scanner; then, the 3D model of the prostheses and their negative molds could be designed with specific software; lastly, with resin molds fabricated by the rapid prototyping machine, the prostheses could be produced directly and quickly. Fifteen patients with maxillofacial defects received prosthesis rehabilitation provided by the established system. The total clinical time used for each patient was only 4 hours over 2 appointments on average. The contours of the prostheses coordinated properly with the appearance of the patients, and the uniform-thickness border sealed well to adjacent tissues. All of the patients were satisfied with their prostheses. The rapid simulative rehabilitation system of maxillofacial defects is approaching completion. It could provide an advanced technological solution for the Army in cases of maxillofacial defect rehabilitation.

  7. Tissue-engineered rhesus monkey nerve grafts for the repair of long ulnar nerve defects: similar outcomes to autologous nerve grafts

    Directory of Open Access Journals (Sweden)

    Chang-qing Jiang

    2016-01-01

    Full Text Available Acellular nerve allografts can help preserve normal nerve structure and extracellular matrix composition. These allografts have low immunogenicity and are more readily available than autologous nerves for the repair of long-segment peripheral nerve defects. In this study, we repaired a 40-mm ulnar nerve defect in rhesus monkeys with tissue-engineered peripheral nerve, and compared the outcome with that of autograft. The graft was prepared using a chemical extract from adult rhesus monkeys and seeded with allogeneic Schwann cells. Pathomorphology, electromyogram and immunohistochemistry findings revealed the absence of palmar erosion or ulcers, and that the morphology and elasticity of the hypothenar eminence were normal 5 months postoperatively. There were no significant differences in the mean peak compound muscle action potential, the mean nerve conduction velocity, or the number of neurofilaments between the experimental and control groups. However, outcome was significantly better in the experimental group than in the blank group. These findings suggest that chemically extracted allogeneic nerve seeded with autologous Schwann cells can repair 40-mm ulnar nerve defects in the rhesus monkey. The outcomes are similar to those obtained with autologous nerve graft.

  8. Biomaterial-Stabilized Soft Tissue Healing for Healing of Critical-Sized Bone Defects: the Masquelet Technique.

    Science.gov (United States)

    Tarchala, Magdalena; Harvey, Edward J; Barralet, Jake

    2016-03-01

    Critical-sized bone defects present a significant burden to the medical community due to their challenging treatment. However, a successful limb-salvaging technique, the Masquelet Technique (MT), has significantly improved the prognosis of many segmental bone defects in helping to restore form and function. Although the Masquelet Technique has proven to be clinically effective, the physiology of the healing it induces is not well understood. Multiple modifiable factors have been implicated by various surgical and research teams, but no single factor has been proven to be critical to the success of the Masquelet Technique. In this review the most recent clinical and experimental evidence that supports and helps to decipher the traditional Masquelet, as well as the modifiable factors and their effect on the success of the technique are discussed. In addition, future developments for the integration of the traditional Masquelet Technique with the use of alternative biomaterials to increase the effectiveness and expand the clinical applicability of the Masquelet Technique are reviewed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Levels of PAH-DNA adducts in cord blood and cord tissue and the risk of fetal neural tube defects in a Chinese population.

    Science.gov (United States)

    Yi, Deqing; Yuan, Yue; Jin, Lei; Zhou, Guodong; Zhu, Huiping; Finnell, Richard H; Ren, Aiguo

    2015-01-01

    Maternal exposure to polycyclic aromatic hydrocarbons (PAHs) has been shown to be associated with an elevated risk for neural tube defects (NTDs). In the human body, PAHs are bioactivated and the resultant reactive epoxides can covalently bind to DNA to form PAH-DNA adducts, which may, in turn, cause transcription errors, changes in gene expression or altered patterns of apoptosis. During critical developmental phases, these changes can result in abnormal morphogenesis. We aimed to examine the relationship between the levels of PAH-DNA adducts in cord blood and cord tissue and the risk of NTDs. From 2010 to 2012, 60 NTD cases and 60 healthy controls were recruited from a population-based birth defects surveillance system in five counties of Shanxi Province in Northern China, where the emission of PAHs remains one of the highest in the country and PAHs exposure is highly prevalent. PAH-DNA adducts in cord blood of 15 NTD cases and 15 control infants, and in cord tissue of 60 NTD cases and 60 control infants were measured using the (32)P-postlabeling method. PAH-DNA adduct levels in cord blood tend to be higher in the NTD group (28.5 per 10(8) nucleotides) compared with controls (19.7 per 10(8) nucleotides), although the difference was not statistically significant (P=0.377). PAH-DNA adducts in cord tissue were significantly higher in the NTD group (24.6 per 10(6) nucleotides) than in the control group (15.3 per 10(6) nucleotides), P=0.010. A positive dose-response relationship was found between levels of PAH-DNA adducts in cord tissue and the risk of NTDs (P=0.009). When the lowest tertile was used as the referent and potential confounding factors were adjusted for, a 1.03-fold (95% CI, 0.37-2.89) and 2.96-fold (95% CI, 1.16-7.58) increase in the risk of NTDs was observed for fetuses whose cord tissue PAH-DNA adduct levels were in the second and highest tertile, respectively. High levels of PAH-DNA adducts in fetal tissues were associated with increased risks of

  10. Diagnostic value of static MR imaging of soft tissue tumours including lesion size, borders and local extend

    International Nuclear Information System (INIS)

    Tacikowska, M.

    2001-01-01

    The usefulness of MR imaging in the evaluation of the degree of soft tissue malignancy is widely discussed. The aim of this study was to analyse the diagnostic value of MR imaging in the evaluation of local progression of soft tissue tumours and to analyse the usefulness of MR imaging in the differential diagnosis (malignant versus benign lesions). One hundred and ten patients with soft tissue tumours were examined by MR imaging (60 men and 50 women, aged 16 to 84 years). MR imaging was carried out with an Elscint 2T or 0.5T unit. Surface coils (passive) or circular polarized coils (active) depending on the localisation of the lesions were used with field vision from 20x24 cm or 40x40 cm, matrices 200x256, 256x256, or 22x315, layer thickness from 3 to 10 mm, gap 20-30%. SE T1 sequences (TR = 500 - 800 ms, TE = 15 - 20 ms) and FSE T2 (Tr = 2000-4500 ms, TE = 96-104 ms) were routinely used in at least two planes: transverse, frontal or saggital, and SE T1 sequences were used after administration of gadolinium Gd-DTPA in 0.1 m - 0.2 mmol/kg body weigh doses. The tumour dimensions by MR imaging were compared with the results of histological examination of samples obtained during surgery (65 cases) - the statistical analysis was performed using Student's t-test, with statistically significant difference accepted at p = 0.05 or less. The borders of the lesions were assessed in the entire material and in the group of 65 patients treated surgically. The latter were compared with the results of histological examination after surgery, thus calculating MR sensitivity and specificity. Static imaging is a valuable diagnostic method for preoperative assesment of the local progression of soft tissue tumours, however it is not suitable for differentiating malignant lesions from benign according to tumour size, borders and local extent. (author)

  11. Tissue reactions to implanted dental amalgam, including assessment by energy dispersive x-ray micro-analysis.

    Science.gov (United States)

    Eley, B M

    1982-11-01

    Dental amalgam, either in the form of a solid rod or as a fine powder was implanted subcutaneously into guinea-pigs and the tissue reactions were examined after varying time periods. The solid rods were enclosed by fibrous capsules within which only extremely limited breakdown occurred. This appears to result from electrolytic corrosion of the gamma 2 (SnHg) phase of the rod's surface. Powdered amalgam induced granulomata and most of the particles of amalgam were actively digested by macrophages and giant cells. This resulted in the progressive loss of mercury and tin from the lesion and the formation of minute particles containing silver and sulphur which became widely distributed throughout the lesion, being associated with basal lamina, collagen and elastic tissue and giving rise to the formation of a tattoo. In contrast, some particles of amalgam, too large to be interiorised, were encapsulated by collagen and persisted almost unchanged. Intracellular small amalgam particles and aggregates of fine particles, resulting from their degradation, were seen within lymph node macrophages. It is extremely likely that the sequence of events leadng to the formation of an amalgam tattoo of the oral mucosa in Man are the same.

  12. Novel feed including bioactive compounds from winery wastes improved broilers' redox status in blood and tissues of vital organs.

    Science.gov (United States)

    Makri, Sotiria; Kafantaris, Ioannis; Stagos, Dimitrios; Chamokeridou, Theodora; Petrotos, Konstantinos; Gerasopoulos, Konstantinos; Mpesios, Anastasios; Goutzourelas, Nikolaos; Kokkas, Stylianos; Goulas, Panagiotis; Komiotis, Dimitrios; Kouretas, Dimitrios

    2017-04-01

    Currently, there is a great interest in the production of animal feed with antioxidant activity. The aim of this study was to examine the potential antioxidant effects of a feed supplemented with grape pomace (GP), a winery by-product with high environmental load, in chickens. Broilers of 15 days post birth were separated into two groups fed either with standard diet or with diet supplemented with GP for 35 days. Blood and tissues collections were performed after feeding for 15 and 35 days with the experimental diet (i.e. at 30 and 50 days post birth). Free radical toxicity markers, namely thiobarbituric acid reactive substances, protein carbonyls, total antioxidant capacity, reduced glutathione, catalase activity and rate of H 2 O 2 decomposition were determined in blood and tissues of vital organs. The results indicated that feed supplemented with GP decreased oxidative stress-induced toxic effects and improved chickens' redox status, and so it may also improve their wellness and productivity. On the other hand, this exploitation of GP may solve problems of environmental pollution in areas with wineries. Copyright © 2017. Published by Elsevier Ltd.

  13. Ethical aspects of soft tissue engineering for congenital birth defects in children : what do experts in the field say?

    NARCIS (Netherlands)

    Oerlemans, A.J.; Rodrigues, Catarina; Verkerk, M.A.; van den Berg, P.P.; Dekkers, W.J.M.

    This article is part of the EuroSTEC project, which aims at developing tissue engineering-based treatments for structural disorders present at birth. EuroSTEC is positioned at the intersection of three areas with their own ethical issues: (1) regenerative medicine, (2) research with pregnant women

  14. Ethical aspects of soft tissue engineering for congenital birth defects in children - what do experts in the field say?

    NARCIS (Netherlands)

    Oerlemans, A.J.M.; Rodrigues, C.H.; Verkerk, M.A.; Berg, P.P. van den; Dekkers, W.J.M.

    2010-01-01

    This article is part of the EuroSTEC project, which aims at developing tissue engineering-based treatments for structural disorders present at birth. EuroSTEC is positioned at the intersection of three areas with their own ethical issues: (1) regenerative medicine, (2) research with pregnant women

  15. The use of beta-tricalcium phosphate and bovine bone matrix in the guided tissue regeneration treatment of deep infra-bony defects

    Directory of Open Access Journals (Sweden)

    Luković Natalija

    2009-01-01

    Full Text Available Introduction. The primary goal of bone regeneration procedures with application of various regenerative biologic agents and biomaterials is to facilitate the formation of periodontal tissues lost as a result of periodontitis. Objective. The aim of the study was to compare clinical outcome of the guided tissue regeneration (GTR treatment with the use of β-tricalcium phosphate and with bovine bone matrix in human deep intra-osseous defects. Methods. Twenty-one systemically healthy subjects with moderate to advanced periodontitis, between 30 and 56 years of age, 11 females and 10 males, were selected. Patients having two similar inter-proximal defects with pocket probing depths following initial therapy greater than 5 mm were recruited for the study. Experimental sites were grafted with pure β-tricalcium phosphate biomaterial (Cerasorb® and a biomembrane, while control sites were treated with bovine-bone hydroxiapatite xenograft (Bio-oss® and a biomembrane. Immediately before surgery and 12 months after surgery, pocket probing depth (PPD, epithelial attachment level (EAL and gingival recession (GR were evaluated. Results. In the experimental group PPD amounted to 6.76±0.83 mm before surgery, and decreased significantly to 2.67±0.48 mm 12 months following surgery, while in the control group PPD significantly decreased from 7.14±0.65 mm presurgically to 2.85±0.57 mm postsurgically. After one year, EAL gain was 2.76±0.99 mm in the experimental group, and 3.24±0.16 mm in the control group. After twelve months postoperatively GR amounted to 1.33±0.79 mm in the experimental group and to 1.05±0.80 mm in the control group. No statistically significant differences for PPD reduction, EAL gain and GR increase were detected between the groups. Conclusion. Results from the present study indicate that GTR treatment of deep intra-osseous defects with Bio-oss® and Cerasorb® resulted in clinically and statistically significant improvement of EAL gain

  16. The in vivo evaluation of tissue-based biomaterials in a rat full-thickness abdominal wall defect model.

    Science.gov (United States)

    Bryan, Nicholas; Ahswin, Helen; Smart, Neil; Bayon, Yves; Wohlert, Stephen; Hunt, John A

    2014-05-01

    Hernias are defects in which an anatomical fascia is breached resulting in ectopic positioning of an organ into an orifice which routinely does not contain it. Intervention often involves repositioning translocated organs and repair of damaged fascia using exogenous grafts. Despite hernia prevalence, repairs can still fail due to postoperative complications, such as chronic pain and decreased mobility. This study compared repair capacities and characterized the foreign body response elicited by a number of hernia repair grafts to deduce their bulk inflammatory properties while also concluding the point in their fabrication when these are inferred. Materials derived from human dermis (Alloderm(®) ), porcine dermis (Permacol™, patch A, patch D and Strattice(®) ), porcine small-intestinal submucosa (Surgisis™) and a synthetic (multifilament Surgipro™) were implanted into a rat full-thickness abdominal wall excision model, incubated for up to 2 years and characterized histopathologically. Surgisis™ resorbed the fastest of the materials tested (1-3 months) resulting in a mechanically stable parietal peritoneum. Decellularization using sodium dodecyl sulfate (patch A) stimulated a large early inflammatory response which ultimately may have contributed to increased resorption of porcine dermal matrix however the remaining materials typically persisted throughout the 2-year incubation. Cross-linking porcine dermis using 1,6-hexamethylene disocyanate (vs. an identical noncross-linked counterpart) showed no difference in cell recruitment or material integration over 2 years. Typically Strattice(®) and Alloderm(®) recruited larger early populations of cells than Permacol™; however, over extended periods of time in vivo this response normalized. Copyright © 2013 Wiley Periodicals, Inc.

  17. Arabidopsis cpFtsY mutants exhibit pleiotropic defects including an inability to increase iron deficiency-inducible root Fe(III) chelate reductase activity.

    Science.gov (United States)

    Durrett, Timothy P; Connolly, Erin L; Rogers, Elizabeth E

    2006-08-01

    All plants, except for the grasses, must reduce Fe(III) to Fe(II) in order to acquire iron. In Arabidopsis, the enzyme responsible for this reductase activity in the roots is encoded by FRO2. Two Arabidopsis mutants, frd4-1 and frd4-2, were isolated in a screen for plants that do not induce Fe(III) chelate reductase activity in their roots in response to iron deficiency. frd4 mutant plants are chlorotic and grow more slowly than wild-type Col-0 plants. Additionally, frd4 chloroplasts are smaller in size and possess dramatically fewer thylakoid membranes and grana stacks when compared with wild-type chloroplasts. frd4 mutant plants express both FRO2 and IRT1 mRNA normally in their roots under iron deficiency, arguing against any defects in systemic iron-deficiency signaling. Further, transgenic frd4 plants accumulate FRO2-dHA fusion protein under iron-deficient conditions, suggesting that the frd4 mutation acts post-translationally in reducing Fe(III) chelate reductase activity. FRO2-dHA appears to localize to the plasma membrane of root epidermal cells in both Col-0 and frd4-1 transgenic plants when grown under iron-deficient conditions. Map-based cloning revealed that the frd4 mutations reside in cpFtsY, which encodes a component of one of the pathways responsible for the insertion of proteins into the thylakoid membranes of the chloroplast. The presence of cpFtsY mRNA and protein in the roots of wild-type plants suggests additional roles for this protein, in addition to its known function in targeting proteins to the thylakoid membrane in chloroplasts.

  18. Brain tissue aspiration neural tube defect Aspiração de tecido cerebral em casos de defeitos de fechamento do tubo neural

    Directory of Open Access Journals (Sweden)

    Luiz Cesar Peres

    2005-09-01

    Full Text Available The study aimed to find out how frequent is brain tissue aspiration and if brain tissue heterotopia could be found in the lung of human neural tube defect cases. Histological sections of each lobe of both lungs of 22 fetuses and newborn with neural tube defect were immunostained for glial fibrillary acidic protein (GFAP. There were 15 (68.2% females and 7 (31.8% males. Age ranged from 18 to 40 weeks of gestation (mean= 31.8. Ten (45.5% were stillborn, the same newborn, and 2 (9.1% were abortuses. Diagnosis were: craniorrhachischisis (9 cases, 40.9%, anencephaly (8 cases, 36,4%, ruptured occipital encephalocele and rachischisis (2 cases, 9.1% each, and early amniotic band disruption sequence (1 case, 4.5%. Only one case (4.5% exhibited GFAP positive cells inside bronchioles and alveoli admixed to epithelial amniotic squames. No heterotopic tissue was observed in the lung interstitium. We concluded that aspiration of brain tissue from the amniotic fluid in neural tube defect cases may happen but it is infrequent and heterotopia was not observed.O objetivo do estudo foi identificar qual a freqüência de aspiração de tecido cerebral e a existência de heterotopia nos pulmões de casos humanos de defeito de fechamento do tubo neural através da reação imuno-histoquímica para proteína fibrilar glial ácida (GFAP em cortes histológicos de todos os lobos de ambos os pulmões de 22 casos de fetos e neonatos com defeito de fechamento do tubo neural. Havia 15 casos femininos (68,2% e 7 masculinos (31,8%, com idade gestacional variando de 18 a 40 semanas (média= 31,8, sendo natimortos e neomortos 10 (45,5% cada e 2 (9,1% abortos. Os diagnósticos foram: Craniorraquisquise (9 casos, 40,9%, anencefalia (8 casos, 36,4%, encefalocele occipital rota e raquisquise (2 casos, 9,1% e 1 (4,5%caso de seqüência de disruptura amniótica precoce. Somente 1 caso (4,5% apresentou células positivas dentro de bronquíolos e alvéolos em meio a células epiteliais

  19. Radiographic and ultrasonographic features of uroliths and other urinary tract filling defects

    International Nuclear Information System (INIS)

    Johnston, G.R.; Walter, P.A.; Feeney, D.A.

    1986-01-01

    Radiopaque uroliths and nonradiopaque (water density) uroliths are filling defects encountered in the urinary tracts of dogs and cats. Other free luminal and attached soft tissue density filling defects encountered during uroradiographic special procedures include blood clots, air bubbles, hematomas, granulomas, abscesses, inflammatory and neoplastic polyps. Nonradiopaque uroliths cannot be identified on survey radiographs from other soft tissue dense structures. Gray scale ultrasonography can be used to differentiate nonradiopaque (water dense) uroliths from other soft tissue attached or free luminal filling defects of the excretory pathway. The differential radiographic features of filling defects encountered during cystography and urethrography are described and illustrated

  20. PXR (NR1I2): splice variants in human tissues, including brain, and identification of neurosteroids and nicotine as PXR activators

    International Nuclear Information System (INIS)

    Lamba, Vishal; Yasuda, Kazuto; Lamba, Jatinder K.; Assem, Mahfoud; Davila, Julio; Strom, Stephen; Schuetz, Erin G.

    2004-01-01

    To gain insight on the expression of pregnane X receptor (PXR), we analyzed PXR.1 and PXR alternatively spliced transcripts in a panel of 36 human tissues. PXR.1 was expressed in many more tissues than previously determined, including human bone marrow and select regions of the human brain. In each of these tissues, we observed alternative splicing of various exons of PXR that generated multiple distinct PXR isoforms. The most abundant PXR alternative mRNA transcripts lacked 111 nucleotides, deleting 37 amino acids from the PXR LBD (PXR.2), or lacked 123 nt, deleting 41 amino acids from the PXR LBD (PXR.3). CYP3A4, a gene transcriptionally regulated by PXR, showed incomplete overlap with PXR in its tissue distribution. Quantitation of PXR mRNAs in human liver demonstrated that PXR.2 and PXR.3 represented 6.7% and 0.32% of total PXR mRNA transcripts. Brain expression of PXR prompted analysis of whether some brain acting chemicals were PXR ligands. The neurosteroids allopregnanolone and pregnanolone activated PXR and induced transcription of a CYP3A4-luciferase reporter. Nicotine, the psychoactive and addictive chemical in cigarettes, and a known inducer of brain CYP2B6, was an efficacious activator of PXR and inducer of CYP3A4 transcription. Because nicotine activation of PXR will enhance metabolism of nicotine to the non-psychoactive cotinine, these results provide one molecular mechanism for the development of tolerance to nicotine. Moreover, the identification of PXR in many human tissues, such as brain, and activation by tissue specific ligands (such as neurosteroids) suggests additional biological roles for this receptor in these tissues

  1. R5-SHIV induces multiple defects in T cell function during early infection of rhesus macaques including accumulation of T reg cells in lymph nodes.

    Directory of Open Access Journals (Sweden)

    Michael Santosuosso

    2011-04-01

    Full Text Available HIV-1 is a pathogen that T cell responses fail to control. HIV-1gp120 is the surface viral envelope glycoprotein that interacts with CD4 T cells and mediates entry. HIV-1gp120 has been implicated in immune dysregulatory functions that may limit anti-HIV antigen-specific T cell responses. We hypothesized that in the context of early SHIV infection, immune dysregulation of antigen-specific T-effector cell and regulatory functions would be detectable and that these would be associated or correlated with measurable concentrations of HIV-1gp120 in lymphoid tissues.Rhesus macaques were intravaginally inoculated with a Clade C CCR5-tropic simian-human immunodeficiency virus, SHIV-1157ipd3N4. HIV-1gp120 levels, antigen-specificity, levels of apoptosis/anergy and frequency and function of Tregs were examined in lymph node and blood derived T cells at 5 and 12 weeks post inoculation.We observed reduced responses to Gag in CD4 and gp120 in CD8 lymph node-derived T cells compared to the peripheral blood at 5 weeks post-inoculation. Reduced antigen-specific responses were associated with higher levels of PD-1 on lymph node-derived CD4 T cells as compared to peripheral blood and uninfected lymph node-derived CD4 T cells. Lymph nodes contained increased numbers of Tregs as compared to peripheral blood, which positively correlated with gp120 levels; T regulatory cell depletion restored CD8 T cell responses to Gag but not to gp120. HIV gp120 was also able to induce T regulatory cell chemotaxis in a dose-dependent, CCR5-mediated manner. These studies contribute to our broader understanding of the ways in which HIV-1 dysregulates T cell function and localization during early infection.

  2. Improved application of the electrophoretic tissue clearing technology, CLARITY, to intact solid organs including brain, pancreas, liver, kidney, lung, and intestine.

    Science.gov (United States)

    Lee, Hyunsu; Park, Jae-Hyung; Seo, Incheol; Park, Sun-Hyun; Kim, Shin

    2014-12-21

    Mapping of tissue structure at the cellular, circuit, and organ-wide scale is important for understanding physiological and biological functions. A bio-electrochemical technique known as CLARITY used for three-dimensional anatomical and phenotypical mapping within transparent intact tissues has been recently developed. This method provided a major advance in understanding the structure-function relationships in circuits of the nervous system and organs by using whole-body clearing. Thus, in the present study, we aimed to improve the original CLARITY procedure and developed specific CLARITY protocols for various intact organs. We determined the optimal conditions for reducing bubble formation, discoloration, and depositing of black particles on the surface of tissue, which allowed production of clearer organ images. We also determined the appropriate replacement cycles of clearing solution for each type of organ, and convincingly demonstrated that 250-280 mA is the ideal range of electrical current for tissue clearing. We then acquired each type of cleared organs including brain, pancreas, liver, lung, kidney, and intestine. Additionally, we determined the images of axon fibers of hippocampal region, the Purkinje layer of cerebellum, and vessels and cellular nuclei of pancreas. CLARITY is an innovative biochemical technology for the structural and molecular analysis of various types of tissue. We developed improved CLARITY methods for clearing of the brain, pancreas, lung, intestine, liver, and kidney, and identified the appropriate experimental conditions for clearing of each specific tissue type. These optimized methods will be useful for the application of CLARITY to various types of organs.

  3. Quality of Newly Formed Cartilaginous Tissue in Defects of Articular Surface after Transplantation of Mesenchymal Stem Cells in a Composite Scaffold Based on Collagen I with Chitosan Micro- and Nanofibres

    Czech Academy of Sciences Publication Activity Database

    Nečas, A.; Plánka, L.; Srnec, R.; Crha, M.; Hlučilová, Jana; Klíma, Jiří; Starý, L.; Křen, L.; Amler, Evžen; Vojtová, L.; Jančář, J.; Gál, P.

    2010-01-01

    Roč. 59, č. 4 (2010), s. 605-614 ISSN 0862-8408 R&D Projects: GA MŠk 2B06130 Institutional research plan: CEZ:AV0Z50450515; CEZ:AV0Z50390512 Keywords : Cartilaginous Tissue * Defects of Articular Surface * Mesenchymal Stem Cells Subject RIV: CE - Biochemistry Impact factor: 1.646, year: 2010

  4. Defect of the Eyelids.

    Science.gov (United States)

    Lu, Guanning Nina; Pelton, Ron W; Humphrey, Clinton D; Kriet, John David

    2017-08-01

    Eyelid defects disrupt the complex natural form and function of the eyelids and present a surgical challenge. Detailed knowledge of eyelid anatomy is essential in evaluating a defect and composing a reconstructive plan. Numerous reconstructive techniques have been described, including primary closure, grafting, and a variety of local flaps. This article describes an updated reconstructive ladder for eyelid defects that can be used in various permutations to solve most eyelid defects. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. [Ora-maxillofacial traumatic defects reconstruction with free flaps].

    Science.gov (United States)

    Peng, Xin; Mao, Chi; Zhang, Yi; Zhang, Lei; An, Jin-gang; Yu, Guang-yan

    2008-11-01

    To evaluate the application, indications and outcomes of free flaps for ora-maxillofacial traumatic defects reconstruction. Twenty consecutive cases of ora-maxillofacial the traumatic defects reconstruction with free flaps were reviewed. All clinical data including causes of injuries, the type of defects, selection of free flaps, perioperative complications and the follow-up were analyzed. All the cases underwent free flap reconstruction for ora-maxillofacial traumatic defects: 8 cases with soft tissue defects, 12 cases with soft and hard tissue defects. Fifteen patients received two-stage operation and 5 patients underwent primary reconstruction at the time of debridement or fracture reduction. Twenty free flaps were applied for the reconstruction, 11 cases with fibula flap, 1 case with iliac crest free flap, 7 cases with radial forearm flap and 1 case with scapula flap. No flap failure occurred. The successful rate of free flaps transfer was 100%. The free flaps transfer is reliable and can reconstruct the ora-maxillofacial traumatic soft and hard tissue defects. Fibula and radial forearm free flap are the most common used flaps. Early aggressive surgery with free flaps transfer for traumatic defects can prevent the scar contracture and tissue displace, which can shorten the treatment period and improve the final outcome.

  6. A novel application of biosynthetic tissue-engineered tridimensional implant on large tendon defects: a comprehensive, detailed, in vivo investigation with significant clinical value.

    Science.gov (United States)

    Moshiri, Ali; Oryan, Ahmad; MeimandiParizi, Abdolhamid

    2013-01-01

    This study was designed to investigate the effect of a biosynthetic implant on tendon healing in vivo. Fifty white New Zealand male rabbits were randomly divided into two groups, namely treated (n = 25) and control (n = 25) groups. A large gap was created in the Achilles tendon and was maintained by Kessler pattern. In the treated group, the implant was inserted in the injured area. No implant was used in the control group. Contrast radiography, hematology, and clinical examination were conducted during the course of the experiment. The animals were euthanized at 60 days post injury (DPI) and their Achilles tendons were subjected to the gross, histopathologic, and biomechanical analyses and the hydroxyproline content of these tendons was also evaluated. Another five treated animals, as a pilot group, were used to define the inflammatory reaction at 10 DPI. Severe inflammatory reaction was initiated by the partially degraded implant, at 10 DPI. However, at 60 DPI, the inflammation subsided, the implant was mostly removed but a few small remnants were still present in the injured area. The newly formed tendon, properly aligned along the longitudinal axis of the Achilles tendon replaced the collagen implant. In the control tendons, a loose areolar connective tissue which tightly adhered to the peri-tendinous tissue was the only regenerated structure in the injured area. At this stage, the treated tendons showed significantly higher ultimate strength (p = 0.001), yield strength (p = 0.001), and stiffness (p = 0.001) compared with the control ones. Application of the biosynthetic implant was a safe and effective option in managing the large tendon defects and could be considered as a substitute for autografts in clinical practice.

  7. Birth Defects

    Science.gov (United States)

    A birth defect is a problem that happens while a baby is developing in the mother's body. Most birth defects happen during the first 3 months of ... in the United States is born with a birth defect. A birth defect may affect how the ...

  8. HIV-1 genome is often defective in PBMCs and rectal tissues after long-term HAART as a result of APOBEC3 editing and correlates with the size of reservoirs.

    Science.gov (United States)

    Fourati, Slim; Lambert-Niclot, Sidonie; Soulie, Cathia; Malet, Isabelle; Valantin, Marc Antoine; Descours, Benjamin; Ait-Arkoub, Zaina; Mory, Benoit; Carcelain, Guislaine; Katlama, Christine; Calvez, Vincent; Marcelin, Anne Geneviève

    2012-10-01

    Precise characterization of viruses present in reservoirs in long-term pretreated patients will be a major issue to consider in the context of viral eradication. We assessed the frequency of defective viruses present in cellular reservoirs. Peripheral blood mononuclear cells (PBMCs) and rectal biopsy samples were compared between five patients on successful long-term highly active antiretroviral therapy (HAART) (>7 years without blips) and five untreated patients. Molecular cloning and sequencing of the reverse transcriptase region were used to detect the presence of and quantify in-frame stop codons in HIV quasi-species. The relationship between the size of the reservoir and the frequency of defective genomes was assessed. Defective genomes were systematically detected in all patients on long-term HAART in both compartments (PBMCs and rectal tissues), with a higher level of defective genomes per sample compared with PBMCs of untreated patients. A high level of defective genomes was correlated with a small size of HIV proviral DNA. Regarding the nucleotide context, guanine (G) to adenine (A) substitution at tryptophan positions was responsible for the appearance of 89% of all in-frame stop codons in the context of G-to-A hypermutation, likely reflecting APOBEC3 footprints on the viral genome. We propose a scenario whereby defective genomes accumulate during HAART treatment, eventually reaching a viral extinction threshold. In the context of viral eradication, measurement of the relative amounts of defective and non-defective viruses (by molecular cloning and ultradeep sequencing) should be used as a new criterion for eradicating HIV.

  9. Quantification of Adipose Tissue and Muscle Mass Based on Computed Tomography Scans: Comparison of Eight Planimetric and Diametric Techniques Including a Step-By-Step Guide.

    Science.gov (United States)

    Irlbeck, Thomas; Janitza, Silke; Poros, Balázs; Golebiewski, Monika; Frey, Lorenz; Paprottka, Philipp M; da Silva, Teresa; Irlbeck, Michael; Böcker, Wolfgang; Weig, Thomas

    2018-01-23

    Recent scientific work proved that knowledge about body composition beyond the body mass index is essential. Both adipose tissue and muscular status are determining risk factors of morbidity and mortality. Analysis of single cross-sectional computed tomography (CT) images, acquired during routine care only to prevent additional radiation exposure, provide a detailed insight into the body composition of chronically and critically ill patients. This retrospective study included 490 trauma patients of whom a whole-body multiple detector CT scan was acquired at admission. From a single cross-sectional CT, we compared eight diametric and planimetric techniques for the assessment of core muscle mass as well as visceral and subcutaneous adipose tissue. Furthermore, we derived formulas for converting the measurement results of various techniques into each other. For intra- and interobserver reliability, we obtained intraclass correlation coefficients (ICCs) ranging from 0.947 to 0.997 (intraobserver reliability) and from 0.850 to 0.998 (interobserver reliability) for planimetric measurements. Diametric techniques conferred lower ICCs with 0.851-0.995 and 0.833-0.971, respectively. Overall, area-based measurements of abdominal adipose tissue yielded highly correlated results with diametric measures of obesity. For example, the Pearson correlation of visceral adipose tissue and sagittal abdominal diameter was 0.87 for male and 0.82 for female patients. Planimetric and diametric muscle measurements correlated best for lean psoas area and bilateral diametric measurement of the psoas with a Pearson correlation of 0.90 and 0.93 for male and female patients, respectively. Planimetric measurements should remain the gold standard to describe fat and muscle compartments. Diametric measurements could however serve as a surrogate if planimetric techniques are not readily available or feasible as for example in large registries. © 2018 S. Karger AG, Basel.

  10. An optimized method for fatty acid analysis, including quantification of trans fatty acids, in human adipose tissue by gas-liquid chromatography

    DEFF Research Database (Denmark)

    Bysted, Anette; Cold, S; Hølmer, Gunhild Kofoed

    1999-01-01

    for 25 min, and finally raised at 25 degrees C/min to 225 degrees C. The trans and cis isomers of18:1 were well separated from each other, as shown by silver-ion thin-layer chromatography. Verification by standardsshowed that the trans 18:1 isomers with a double bond in position 12 or lower were......Considering the need for a quick direct method for measurement of the fatty acid composition including trans isomers ofhuman adipose tissue we have developed a procedure using gas-liquid chromatography (GLC) alone, which is thussuitable for validation of fatty acid status in epidemiological studies...

  11. [Analysis of the clinical application of epidermal growth factor ("Heberprot-P") and bioplastic material ("Collost") in treatment of skin and soft tissues defects in patients with diabetic foot syndrome].

    Science.gov (United States)

    Dibirov, M D; Gadzhimuradov, R U; Koreyba, K A

    2016-01-01

    Currently, there is increasing the number of diabetic foot patients with tissues defects. The local treatment of this pathology against the backdrop of diabetic angiopathy and polyneuropathy is a topical issue. Treatment of wound defects in patients with neuroischemic form of diabetic foot syndrome; study of the effectiveness of collagen implants and gene-therapy technologies in wound closure. The comparative study was conducted for analyzing clinical effects of "Heberprot-P" and bioplastic material "Collost" on wound healing process in patients with verified diagnosis "diabetic foot syndrome" on the base of City Clinical Hospital №81(Moscow) and "Diabetic Foot" center (Kazan). The article shows the availability, methodology, results of combination treatment of wound defects of lower limbs in DFS patients with gen-therapy methods and bioplastic materials based on native type I collagen. The use of bioplastic materials based on native type I collagen for treatment of tissue defects in patients with diabetic foot is preferably than the use of epidermal growth factor.

  12. Novel application of a tissue-engineered collagen-based three-dimensional bio-implant in a large tendon defect model: a broad-based study with high value in translational medicine.

    Science.gov (United States)

    Meimandi-Parizi, Abdolhamid; Oryan, Ahmad; Moshiri, Ali; Silver, Ian A

    2013-08-01

    This study was designed to investigate the effectiveness of a novel tissue-engineered three-dimensional collagen implant on healing of a large tendon-defect model, in vivo. Forty rabbits were divided into two equal groups: treated and control. A 2cm full-thickness gap was created in the left Achilles tendons of all the rabbits. To maintain the gap at the desired length (2cm), a Kessler suture was anchored within the proximal and distal ends of the remaining tendon. In the treated group a collagen implant was inserted in the gap while in the control group the gap was left unfilled. At weekly intervals the animals were examined clinically and their Achilles tendons tested bioelectrically. The hematological parameters and the serum Platelet-Derived Growth Factor of the animals were analyzed at 60 days post injury (DPI) immediately prior to euthanasia. Their injured (left) and normal contralateral Achilles tendons were harvested and examined at gross morphologic level before being subjected to biomechanical testing, and biophysical and biochemical analysis. The treated animals showed superior weight-bearing and greater physical activity than their controls. New dense tendinous tissue with a transverse diameter comparable to that of intact tendons filled the defect area of the treated tendons and had entirely replaced the collagen implant, at 60 DPI. In control lesions the defect was filled with loose areolar connective tissue similar to subcutaneous fascia. Treatment significantly improved the electrical resistance, dry matter, hydroxyproline content, water uptake and water delivery characteristics, of the healing tissue, as well as maximum load, yield load, maximum stress, yield stress and modulus of elasticity of the injured treated tendons compared to those of the control tendons (P<0.05). Use of this three-dimensional collagen implant improved the healing of large tendon defects in rabbits. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Repair of deep tissue defects in the posterior talocrural region using a superficial temporal fascia free flap plus thin split-skin grafting in extensively burned patients: A retrospective case series.

    Science.gov (United States)

    Yang, Xuekang; Zhao, Hui; Liu, Mengdong; Zhang, Yue; Chen, Qiaohua; Li, Zhiqiang; Han, Juntao; Hu, Dahai

    2018-01-01

    The aim of this study was to describe the scheme, surgical procedures, and clinical outcomes for the early repair of deep wounds of the posterior talocrural region in extensively burned patients with a method combining a superficial temporal fascia free flap with thin split-skin grafting.From January 2013 to February 2016, 9 extensively burned patients with deep tissue defects of the posterior talocrural region were treated in our department (2 patients had bilateral deep tissue defects of the posterior talocrural region). All 11 wounds were repaired using a superficial temporal fascia free flap and thin split-skin grafting. After the operation, survival of the fascia flaps and grafted skin was observed, and the appearance and functional recovery of the grafts were evaluated. Follow-up information was reviewed, and complications were documented.All 11 fascia flaps survived completely. Two cases of partial skin necrosis healed after the second application of skin grafts. The appearance and function of recipient sites were well restored in all patients over a follow-up period of 5 to 14 months.Deep tissue defects of the posterior talocrural region can be effectively repaired with our method combining a superficial temporal fascia free flap with thin split-skin grafting. This method offers the advantages of a good appearance, strong resistance to infection, minimal damage at the donor site, short course of disease, and good prognosis. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

  14. Computed tomography of lambdoid calvarial defect in neurofibromatosis

    International Nuclear Information System (INIS)

    Mann, H.; Kozic, Z.; Medinilla, O.R.

    1983-01-01

    A patient with neurofibromatosis is reported in whom cranial computed tomography (CT) revealed a calvarial defect with an associated soft-tissue mass in the region of the left lambdoid suture. This defect has been the subject of several previous reports, having been demonstrated by means of conventional skull radiography. It should be included in the differential diagnosis when a lytic calvarial lesion is found on CT. (orig.)

  15. Change in subcutaneous adipose tissue metabolism and gene network expression during the transition period in dairy cows, including differences due to sire genetic merit.

    Science.gov (United States)

    Khan, M J; Hosseini, A; Burrell, S; Rocco, S M; McNamara, J P; Loor, J J

    2013-04-01

    Adipose metabolism is an essential contributor to the efficiency of milk production, and metabolism is controlled by several mechanisms, including gene expression of critical proteins; therefore, the objective of this study was to determine how lactational state and the genetic merit of dairy cattle affects adipose tissue (AT) metabolism and mRNA expression of genes known to control metabolism. Animals of high (HGM) and low genetic merit (LGM) were fed to requirements, and weekly dry matter intake, milk production, blood glucose, and nonesterified fatty acids were measured. Subcutaneous AT biopsies were collected at -21, 7, 28 and 56 d in milk (DIM). The mRNA expression of genes coding for lipogenic enzymes [phosphoenolpyruvate carboxykinase 1 (soluble) (PCK1), fatty acid synthase (FASN), diacylglycerol O-acyltransferase 2 (DGAT2), and stearoyl-coenzyme A desaturase (SCD)], transcription regulators [peroxisome proliferator-activated receptor γ (PPARG), thyroid hormone responsive (THRSP), wingless-type MMTV integration site family, member 10B (WNT10B), sterol regulatory element binding transcription factor 1 (SREBF1), and adiponectin (ADIPOQ)], lipolytic enzymes [hormone-sensitive lipase (LIPE), patatin-like phospholipase domain containing 2 (PNPLA2), monoglyceride lipase (MGLL), adrenoceptor β-2 (ADRB2), adipose differentiation-related protein (ADFP), and α-β-hydrolase domain containing 5 (ABHD5)], and genes controlling the sensing of intracellular energy [phosphodiesterase 3A (PDE3A); PDE3B; protein kinase, AMP-activated, α-1 catalytic subunit (PRKAA1); PRKAA2; and growth hormone receptor (GHR)] was measured. Dry matter intake, blood glucose, and nonesterified fatty acid concentrations did not differ between genetic merit groups. Milk production was greater for HGM cows from 6 to 8 wk postpartum. As expected, the rates of lipogenesis decreased in early lactation, whereas stimulated lipolysis increased. At 7 DIM, lipogenesis in HGM cows increased as a function

  16. [Repair of skin and soft tissue defects at distal end of finger with serrated flap with digital proper artery and nerve pedicle combined with bilaterally pedicled V-Y advancement flap of the injured finger].

    Science.gov (United States)

    Chang, Shusen; Jin, Wenhu; Wei, Zairong; Sun, Guangfeng; Wang, Bo; Deng, Chengliang; Tang, Xiujun; Zeng, Xueqin; Nie, Kaiyu

    2016-04-01

    To investigate the therapeutic effects of repair of skin and soft tissue defects at distal end of finger with serrated flap with digital proper artery and nerve pedicle combined with bilaterally pedicled V-Y advancement flap of the injured finger. Thirteen patients with skin and soft tissue defects at distal end of 13 fingers were hospitalized from September 2013 to January 2015. After debridement, the wound area of finger ranged from 1.2 cm × 0.8 cm to 1.8 cm × 1.5 cm. Serrated flap with digital proper artery and nerve pedicle combined with bilaterally pedicled V-Y advancement flap of the injured finger were used to repair the defect. The flaps were interruptedly sutured. The areas of bilaterally pedicled V-Y advancement flap and serrated flap with digital proper artery and nerve pedicle ranged from 0.52 to 1.11 and 2.60 to 5.23 cm(2,) respectively. All flaps of 13 patients survived completely. The patients were followed up for 6 to 24 months. The color and texture of the flaps were good. After reconstruction, the finger tips were in round in shape. The appearance of the fingers was consistent with that of the normal fingers, and joint motility was normal. No hook-nail deformity or knuckle dysfunction was found. Sensation of the flaps was estimated as S4, and the distance of two-point discrimination ranged from 2 to 3 mm. The recovery of the joint motion function of the fingers was excellent. Serrated flap with digital proper artery and nerve pedicle, combined with bilaterally pedicled V-Y advancement flap from the injured finger can repair the skin and soft tissue defects at distal end of finger with reliable blood supply and simple operative technic. It also could avoid the formation of deformity subsequent to a linear scar, and a satisfactory appearance with good function could be obtained.

  17. Clinical and radiographic evaluation of Bio-Gen with biocollagen compared with Bio-Gen with connective tissue in the treatment of class II furcation defects: a randomized clinical trial

    Directory of Open Access Journals (Sweden)

    Niloofar Jenabian

    2013-09-01

    Full Text Available OBJECTIVE: Treatment of furcation defects are thought to be challenging. The purpose of this study was to evaluate the clinical and radiographic parameters of Bio-Gen with Biocollagen compared with Bio-Gen with connective tissue in the treatment of Class II furcation defects. MATERIAL AND METHODS: In this clinical trial, 24 patients with Class II furcation defect on a buccal or lingual mandibular molar were recruited. After oral hygiene instruction, scaling and root planing and achievement of acceptable plaque control, the patients were randomly chosen to receive either connective tissue and Bio-Gen (case group or Biocollagen and Bio-Gen (control group. The following parameters were recorded before the first and re-entry surgery (six months later: vertical clinical attachment level (VCAL, gingival index (GI, plaque index (PI, horizontal probing depth (HPD, vertical probing depth (VPD, gingival recession (GR, furcation vertical component (FVC, furcation to alveolar crest (FAC, fornix to base of defect (FBD, and furcation horizontal component (FHC were calculated at the time of first surgery and during re-entry. A digital periapical radiograph was taken in parallel before first surgery and re-entry. The radiographs were then analyzed by digital subtraction. The differences with p value <0.05 were considered significant. RESULTS: Only the mean changes of FAC, FHC, mean of FHC, FBD in re-entry revealed statistically significant differences between the two groups. HPD, VPD, FBD, FAC, and FHC showed statistically significant differences after 6 months in the case group. However, in the control group, statistically significant differences were found in GR and HPD. We did not observe any significant difference in radiographic changes among the two groups. CONCLUSION: The results of this trial indicate that better clinical outcomes can be obtained with connective tissue grafts in combination with bone material compared with a resorbable barrier with bone

  18. Defects in semiconductors

    CERN Document Server

    Romano, Lucia; Jagadish, Chennupati

    2015-01-01

    This volume, number 91 in the Semiconductor and Semimetals series, focuses on defects in semiconductors. Defects in semiconductors help to explain several phenomena, from diffusion to getter, and to draw theories on materials' behavior in response to electrical or mechanical fields. The volume includes chapters focusing specifically on electron and proton irradiation of silicon, point defects in zinc oxide and gallium nitride, ion implantation defects and shallow junctions in silicon and germanium, and much more. It will help support students and scientists in their experimental and theoret

  19. A comparative evaluation of freeze-dried bone allograft with and without bioabsorbable guided tissue regeneration membrane Healiguide® in the treatment of Grade II furcation defects: A clinical study

    Directory of Open Access Journals (Sweden)

    Deept Jain

    2015-01-01

    Full Text Available Background: Furcation defects represent one of the most demanding therapeutic challenges for periodontal therapy. Various treatment modalities have been tried with different success rates. The present study was undertaken to evaluate the efficacy of freeze-dried bone allograft (FDBA with and without bioabsorbable guided tissue regeneration (GTR membrane Healiguide® in the treatment of Grade II furcation defects. Materials and Methods: Ten patients with bilateral Grade II furcation defects were selected for the study. After phase I therapy, subjects were divided into two arms and treated in a split-mouth design. Ten defects were treated with FDBA alone in the control arm. Ten defects were treated with FDBA in conjunction with bioabsorbable GTR membrane Healiguide® in test arm. Clinical parameters like plaque index, gingival index, vertical probing depth, horizontal probing depth, and relative attachment level (RAL were assessed at baseline, 3 months, and 6 months postoperatively. Results: At 6 months, clinical improvement was seen in both the arms with mean pocket depth reduction of 1.2 ± 1.032 mm and 1.7 ± 0.948 mm and mean horizontal probing depth reduction being 2.1 ± 1.969 mm and 1.6 ± 1.264 mm in control and test arm, respectively. Both surgical procedures resulted in a statistically significant reduction in vertical and horizontal probing depths. Conclusion: Both the arms demonstrated a significant improvement in the probing depth, horizontal furcation depth, and RAL at 6 months postsurgery in the treatment of Grade II furcation defects. However, on the intergroup comparison, there was no statistically significant difference in the results achieved between two arms.

  20. Numerical simulation of fluid field and in vitro three-dimensional fabrication of tissue-engineered bones in a rotating bioreactor and in vivo implantation for repairing segmental bone defects.

    Science.gov (United States)

    Song, Kedong; Wang, Hai; Zhang, Bowen; Lim, Mayasari; Liu, Yingchao; Liu, Tianqing

    2013-03-01

    In this paper, two-dimensional flow field simulation was conducted to determine shear stresses and velocity profiles for bone tissue engineering in a rotating wall vessel bioreactor (RWVB). In addition, in vitro three-dimensional fabrication of tissue-engineered bones was carried out in optimized bioreactor conditions, and in vivo implantation using fabricated bones was performed for segmental bone defects of Zelanian rabbits. The distribution of dynamic pressure, total pressure, shear stress, and velocity within the culture chamber was calculated for different scaffold locations. According to the simulation results, the dynamic pressure, velocity, and shear stress around the surface of cell-scaffold construction periodically changed at different locations of the RWVB, which could result in periodical stress stimulation for fabricated tissue constructs. However, overall shear stresses were relatively low, and the fluid velocities were uniform in the bioreactor. Our in vitro experiments showed that the number of cells cultured in the RWVB was five times higher than those cultured in a T-flask. The tissue-engineered bones grew very well in the RWVB. This study demonstrates that stress stimulation in an RWVB can be beneficial for cell/bio-derived bone constructs fabricated in an RWVB, with an application for repairing segmental bone defects.

  1. Defects in hardwood timber

    Science.gov (United States)

    Roswell D. Carpenter; David L. Sonderman; Everette D. Rast; Martin J. Jones

    1989-01-01

    Includes detailed information on all common defects that may aRect hardwood trees and logs. Relationships between manufactured products and those forms of round material to be processed from the tree for conversion into marketable products are discussed. This handbook supersedes Agriculture Handbook No. 244, Grade defects in hardwood timber and logs, by C.R. Lockard, J...

  2. An evaluation of Admedus' tissue engineering process-treated (ADAPT) bovine pericardium patch (CardioCel) for the repair of cardiac and vascular defects.

    Science.gov (United States)

    Strange, Geoff; Brizard, Christian; Karl, Tom R; Neethling, Leon

    2015-03-01

    Tissue engineers have been seeking the 'Holy Grail' solution to calcification and cytotoxicity of implanted tissue for decades. Tissues with all of the desired qualities for surgical repair of congenital heart disease (CHD) are lacking. An anti-calcification tissue engineering process (ADAPT TEP) has been developed and applied to bovine pericardium (BP) tissue (CardioCel, AdmedusRegen Pty Ltd, Perth, WA, Australia) to eliminate cytotoxicity, improve resistance to acute and chronic inflammation, reduce calcification and facilitate controlled tissue remodeling. Clinical data in pediatric patients, and additional pre-market authorized prescriber data demonstrate that CardioCel performs extremely well in the short term and is safe and effective for a range of congenital heart deformations. These data are supported by animal studies which have shown no more than normal physiologic levels of calcification, with good durability, biocompatibility and controlled healing.

  3. Treatment history and outcome of 24 deliveries worldwide after autotransplantation of cryopreserved ovarian tissue, including two new Danish deliveries years after autotransplantation

    DEFF Research Database (Denmark)

    Macklon, Kirsten T; Jensen, Annette Klüver; Loft, Anne

    2014-01-01

    PURPOSE: To report another two successful pregnancies and deliveries resulting from autotransplanted cryopreserved ovarian tissue several years after the autotransplantation procedure took place. Further, to review the literature on the treatment history, number of live births and their outcome so......'s lymphoma. Both suffered from premature ovarian insufficiency after treatment. Because of a pregnancy wish they later had pieces of thawed cortical tissue transplanted to the remaining ovary and the anterior abdominal wall. PubMed was searched for reports of deliveries resulting from cryopreserved ovarian...

  4. Hemophilia as a defect of the tissue factor pathway of blood coagulation: Effect of factors VIII and IX on factor X activation in a continuous-flow reactor

    International Nuclear Information System (INIS)

    Repke, D.; Gemmell, C.H.; Guha, A.; Turitto, V.T.; Nemerson, Y.; Broze, G.J. Jr.

    1990-01-01

    The effect of factors VIII and IX on the ability of the tissue factor-factor VIIa complex to activate factor X was studied in a continuous-flow tubular enzyme reactor. Tissue factor immobilized in a phospholipid bilayer on the inner surface of the tube was exposed to a perfusate containing factors VIIa, VIII, IX, and X flowing at a wall shear rate of 57, 300, or 1130 sec -1 . The addition of factors VIII and IX at their respective plasma concentrations resulted in a further 2 endash-to 3 endash fold increase. The direct activation of factor X by tissue factor-factor VIIa could be virtually eliminated by the lipoprotein-associated coagulation inhibitor. These results suggest that the tissue factor pathway, mediated through factors VIII and IX, produces significant levels of factor Xa even in the presence of an inhibitor of the tissue factor-factor VIIa complex; moreover, the activation is dependent on local shear conditions. These findings are consistent both with a model of blood coagulation in which initiation of the system results from tissue factor and with the bleeding observed in hemophilia

  5. Tissue reactions to the separate implantation of individual constituent phases of dental amalgam, including assessment by energy dispersive X-ray microanalysis.

    Science.gov (United States)

    Eley, B M; Garrett, J R

    1983-04-01

    Soft tissue degradation of the 3 principal amalgam phases have been investigated in relation to their role in the formation of the amalgam tattoo. Each phase, finely powdered, was implanted subcutaneously into the submandibular region of guinea-pigs for periods ranging from 1 week to 1 year. The rates of breakdown were assessed radiographically and the final lesions were examined by light and electron microscopy and X-ray microanalysis. gamma 2 (Sn7Hg) phase degraded rapidly, mainly extracellularly, and did not produce a tattoo. Both mercury and tin disappeared from the lesion. gamma 1 (Ag2Hg3) phase degraded less rapidly, both extra and intracellularly, and produced a small tattoo. Mercury was lost from the lesion. gamma (Ag3Sn) phase degraded slowly, intracellularly, and produced a large tattoo. Tattoos always resulted from persistence of minute particles of silver and sulphur associated with basal lamina and connective tissue.

  6. Defects and defect processes in nonmetallic solids

    CERN Document Server

    Hayes, W

    2004-01-01

    This extensive survey covers defects in nonmetals, emphasizing point defects and point-defect processes. It encompasses electronic, vibrational, and optical properties of defective solids, plus dislocations and grain boundaries. 1985 edition.

  7. Tendon tissue engineering and its role on healing of the experimentally induced large tendon defect model in rabbits: a comprehensive in vivo study.

    Science.gov (United States)

    Meimandi-Parizi, Abdolhamid; Oryan, Ahmad; Moshiri, Ali

    2013-01-01

    Healing of large tendon defects is challenging. We studied the role of collagen implant with or without polydioxanone (PDS) sheath on the healing of a large Achilles tendon defect model, in rabbits. Sixty rabbits were divided into three groups. A 2 cm gap was created in the left Achilles tendon of all rabbits. In the control lesions, no implant was used. The other two groups were reconstructed by collagen and collagen-PDS implants respectively. The animals were clinically examined at weekly intervals and their lesions were observed by ultrasonography. Blood samples were obtained from the animals and were assessed for hematological analysis and determination of serum PDGF level, at 60 days post injury (DPI). The animals were then euthanized and their lesions were assessed for gross and histopathology, scanning electron microscopy, biomechanical testing, dry matter and hydroxyproline content. Another 65 pilot animals were also studied grossly and histopathologically to define the host implant interaction and graft incorporation at serial time points. The treated animals gained significantly better clinical scoring compared to the controls. Treatment with collagen and collagen-PDS implants significantly increased the biomechanical properties of the lesions compared to the control tendons at 60DPI (Ptendon. Implantation of the bioimplants had a significant role in initiating tendon healing and the implants were biocompatible, biodegradable and safe for application in tendon reconstructive surgery. The results of the present study may be valuable in clinical practice.

  8. Iatrogenic Urethral Defect Repairment: A Case Report

    Directory of Open Access Journals (Sweden)

    Ulas Fidan

    2013-10-01

    Full Text Available    Iatrogenic urethral defect is a complication that occurs after vaginal surgical procedures. Many surgical methods according to place of defect are described in case of injury of urethra. In this article, we reported the repairment of distal urethral defect with the help of greft taken from labia minor. This defect is made by the excision of the granulation tissue that occurred after chronic paraurethral  gland infection.

  9. The Adjunctive Effect of Platelet-Rich Fibrin to Connective Tissue Graft in the Treatment of Buccal Recession Defects: Results of a Randomized, Parallel-Group Controlled Trial.

    Science.gov (United States)

    Keceli, Huseyin Gencay; Kamak, Gulen; Erdemir, Ebru Olgun; Evginer, Mustafa Serdar; Dolgun, Anil

    2015-11-01

    Platelet-rich fibrin (PRF) is an autologous preparation that has encouraging effects in healing and regeneration. The aim of this trial is to evaluate the effectiveness of coronally advanced flap (CAF) + connective tissue graft (CTG) + PRF in Miller Class I and II recession treatment compared to CAF + CTG. Forty patients were treated surgically with either CAF + CTG + PRF (test group) or CAF + CTG (control group). Clinical parameters of plaque index, gingival index, vertical recession (VR), probing depth, clinical attachment level (CAL), keratinized tissue width (KTW), horizontal recession (HR), mucogingival junction localization, and tissue thickness (TT) were recorded at baseline and 3 and 6 months after surgery. Root coverage (RC), complete RC (CRC), attachment gain (AG), and keratinized tissue change (KTC) were also calculated. All individuals completed the entire study period. At baseline, mean VR, HR, CAL, KTW, and TT values were similar (P >0.05). In both groups, all parameters showed significant improvement after treatment (P effect of PRF on recession treatment with CAF + CTG, and additional trials are needed.

  10. Multifocal metastatic chordoma to the soft tissues of the fingertips: a case report including sonographic features and a review of the literature.

    Science.gov (United States)

    Smith, Zachary; Girard, Nicole; Hansford, Barry G

    2018-03-01

    Chordoma is a rare, locally aggressive tumor which commonly metastasizes, most often to the lung, liver, and spine. In this case report, a 59-year-old male with history of sacral chordoma and pulmonary metastases presented to the emergency department with swelling and discoloration of multiple left fingertips. The initial radiographs led to a presumptive diagnosis of gout, which did not respond to medical therapy. An ultrasound demonstrated multiple solid masses with vascular hyperechoic septations which were subsequently biopsied and proven to be metastatic chordoma. Metastatic disease to the hand is a well documented but rare manifestation of many malignancies. The clinical presentation and radiographic features of multifocal hand metastases may mimic entities such as systemic deposition and granulomatous diseases. To the best of our knowledge, this is the first case report of soft tissue chordoma metastases to the fingertips as well as the first reported sonographic description of chordoma metastases.

  11. Digital Genome-Wide ncRNA Expression, Including SnoRNAs, across 11 Human Tissues Using PolyA-Neutral Amplification

    Science.gov (United States)

    Castle, John C.; Armour, Christopher D.; Löwer, Martin; Haynor, David; Biery, Matthew; Bouzek, Heather; Chen, Ronghua; Jackson, Stuart; Johnson, Jason M.; Rohl, Carol A.; Raymond, Christopher K.

    2010-01-01

    Non-coding RNAs (ncRNAs) are an essential class of molecular species that have been difficult to monitor on high throughput platforms due to frequent lack of polyadenylation. Using a polyadenylation-neutral amplification protocol and next-generation sequencing, we explore ncRNA expression in eleven human tissues. ncRNAs 7SL, U2, 7SK, and HBII-52 are expressed at levels far exceeding mRNAs. C/D and H/ACA box snoRNAs are associated with rRNA methylation and pseudouridylation, respectively: spleen expresses both, hypothalamus expresses mainly C/D box snoRNAs, and testes show enriched expression of both H/ACA box snoRNAs and RNA telomerase TERC. Within the snoRNA 14q cluster, 14q(I-6) is expressed at much higher levels than other cluster members. More reads align to mitochondrial than nuclear tRNAs. Many lincRNAs are actively transcribed, particularly those overlapping known ncRNAs. Within the Prader-Willi syndrome loci, the snoRNA HBII-85 (group I) cluster is highly expressed in hypothalamus, greater than in other tissues and greater than group II or III. Additionally, within the disease locus we find novel transcription across a 400,000 nt span in ovaries. This genome-wide polyA-neutral expression compendium demonstrates the richness of ncRNA expression, their high expression patterns, their function-specific expression patterns, and is publicly available. PMID:20668672

  12. Digital genome-wide ncRNA expression, including SnoRNAs, across 11 human tissues using polyA-neutral amplification.

    Directory of Open Access Journals (Sweden)

    John C Castle

    Full Text Available Non-coding RNAs (ncRNAs are an essential class of molecular species that have been difficult to monitor on high throughput platforms due to frequent lack of polyadenylation. Using a polyadenylation-neutral amplification protocol and next-generation sequencing, we explore ncRNA expression in eleven human tissues. ncRNAs 7SL, U2, 7SK, and HBII-52 are expressed at levels far exceeding mRNAs. C/D and H/ACA box snoRNAs are associated with rRNA methylation and pseudouridylation, respectively: spleen expresses both, hypothalamus expresses mainly C/D box snoRNAs, and testes show enriched expression of both H/ACA box snoRNAs and RNA telomerase TERC. Within the snoRNA 14q cluster, 14q(I-6 is expressed at much higher levels than other cluster members. More reads align to mitochondrial than nuclear tRNAs. Many lincRNAs are actively transcribed, particularly those overlapping known ncRNAs. Within the Prader-Willi syndrome loci, the snoRNA HBII-85 (group I cluster is highly expressed in hypothalamus, greater than in other tissues and greater than group II or III. Additionally, within the disease locus we find novel transcription across a 400,000 nt span in ovaries. This genome-wide polyA-neutral expression compendium demonstrates the richness of ncRNA expression, their high expression patterns, their function-specific expression patterns, and is publicly available.

  13. [Ultrasound scanning of the distraction regenerate in case of multilocus elongation of the fragments in patients with defects of long bones].

    Science.gov (United States)

    Menshikova, T I; Borzunov, D Iu; Dolganova, T I

    2014-01-01

    It was done ultrasound examination of distraction regenerates in patients with defect of bone tissue. The first group included 4 patients who had the size of congenital bone tissue defect 15.8±8.1 cm; the second group (3 patients) included posttraumatic defects with defect size 11.75±3.6 cm; the third group (4 patients) included posttraumatic defects with defect size 11±5.3 cm. It was discovered the particularities of distraction regenerate structural condition in case of low level of reparative osteogenesis. In the first group "ischemic" regenerate was characterized by slow formation of bone trabecules. In the second group "ischemic" regenerate had one or two hypo-echogenic cystic-like formations in the intermediate regenerate area. All patients of the third group had organotypic remodeling of the regenerate according to terms of distraction and fixation.

  14. Efficacy of humidity retention bags for the reduced adsorption and improved cleaning of tissue proteins including prion-associated amyloid to surgical stainless steel surfaces.

    Science.gov (United States)

    Secker, T J; Pinchin, H E; Hervé, R C; Keevil, C W

    2015-01-01

    Increasing drying time adversely affects attachment of tissue proteins and prion-associated amyloid to surgical stainless steel, and reduces the efficacy of commercial cleaning chemistries. This study tested the efficacy of commercial humidity retention bags to reduce biofouling on surgical stainless steel and to improve subsequent cleaning. Surgical stainless steel surfaces were contaminated with ME7-infected brain homogenates and left to dry for 15 to 1,440 min either in air, in dry polythene bags or within humidity retention bags. Residual contamination pre/post cleaning was analysed using Thioflavin T/SYPRO Ruby dual staining and microscope analysis. An increase in biofouling was observed with increased drying time in air or in sealed dry bags. Humidity retention bags kept both protein and prion-associated amyloid minimal across the drying times both pre- and post-cleaning. Therefore, humidity bags demonstrate a cheap, easy to implement solution to improve surgical instrument reprocessing and to potentially reduce associated hospital acquired infections.

  15. Optical coherence tomography use in the diagnosis of enamel defects

    Science.gov (United States)

    Al-Azri, Khalifa; Melita, Lucia N.; Strange, Adam P.; Festy, Frederic; Al-Jawad, Maisoon; Cook, Richard; Parekh, Susan; Bozec, Laurent

    2016-03-01

    Molar incisor hypomineralization (MIH) affects the permanent incisors and molars, whose undermineralized matrix is evidenced by lesions ranging from white to yellow/brown opacities to crumbling enamel lesions incapable of withstanding normal occlusal forces and function. Diagnosing the condition involves clinical and radiographic examination of these teeth, with known limitations in determining the depth extent of the enamel defects in particular. Optical coherence tomography (OCT) is an emerging hard and soft tissue imaging technique, which was investigated as a new potential diagnostic method in dentistry. A comparison between the diagnostic potential of the conventional methods and OCT was conducted. Compared to conventional imaging methods, OCT gave more information on the structure of the enamel defects as well as the depth extent of the defects into the enamel structure. Different types of enamel defects were compared, each type presenting a unique identifiable pattern when imaged using OCT. Additionally, advanced methods of OCT image analysis including backscattered light intensity profile analysis and enface reconstruction were performed. Both methods confirmed the potential of OCT in enamel defects diagnosis. In conclusion, OCT imaging enabled the identification of the type of enamel defect and the determination of the extent of the enamel defects in MIH with the advantage of being a radiation free diagnostic technique.

  16. GLUT4 defects in adipose tissue are early signs of metabolic alterations in Alms1GT/GT, a mouse model for obesity and insulin resistance.

    Directory of Open Access Journals (Sweden)

    Francesca Favaretto

    Full Text Available Dysregulation of signaling pathways in adipose tissue leading to insulin resistance can contribute to the development of obesity-related metabolic disorders. Alström Syndrome, a recessive ciliopathy, caused by mutations in ALMS1, is characterized by progressive metabolic alterations such as childhood obesity, hyperinsulinemia, and type 2 diabetes. Here we investigated the role of Alms1 disruption in AT expansion and insulin responsiveness in a murine model for Alström Syndrome. A gene trap insertion in Alms1 on the insulin sensitive C57BL6/Ei genetic background leads to early hyperinsulinemia and a progressive increase in body weight. At 6 weeks of age, before the onset of the metabolic disease, the mutant mice had enlarged fat depots with hypertrophic adipocytes, but without signs of inflammation. Expression of lipogenic enzymes was increased. Pre-adipocytes isolated from mutant animals demonstrated normal adipogenic differentiation but gave rise to mature adipocytes with reduced insulin-stimulated glucose uptake. Assessment of whole body glucose homeostasis revealed glucose intolerance. Insulin stimulation resulted in proper AKT phosphorylation in adipose tissue. However, the total amount of glucose transporter 4 (SLC4A2 and its translocation to the plasma membrane were reduced in mutant adipose depots compared to wildtype littermates. Alterations in insulin stimulated trafficking of glucose transporter 4 are an early sign of metabolic dysfunction in Alström mutant mice, providing a possible explanation for the reduced glucose uptake and the compensatory hyperinsulinemia. The metabolic signaling deficits either reside downstream or are independent of AKT activation and suggest a role for ALMS1 in GLUT4 trafficking. Alström mutant mice represent an interesting model for the development of metabolic disease in which adipose tissue with a reduced glucose uptake can expand by de novo lipogenesis to an obese state.

  17. A quorum sensing-defective mutant of Pectobacterium carotovorum ssp. brasiliense 1692 is attenuated in virulence and unable to occlude xylem tissue of susceptible potato plant stems.

    Science.gov (United States)

    Moleleki, Lucy Novungayo; Pretorius, Rudolph Gustav; Tanui, Collins Kipngetich; Mosina, Gabolwelwe; Theron, Jacques

    2017-01-01

    Pectobacterium carotovorum ssp. brasiliense 1692 (Pcb1692) is an important emerging pathogen of potatoes causing blackleg in the field and soft rot during post-harvest storage. Blackleg diseases involve the bacterial colonization of vascular tissue and the formation of aggregates, also known as biofilms. To understand the role of quorum sensing in vascular colonization by Pcb1692, we generated a Pcb1692ΔexpI mutant strain. Inactivation of expI led to the reduced production of plant cell wall-degrading enzymes (PCWDEs), the inability to produce acyl homoserine lactone (AHL) and reduced virulence in potato tubers and stems. Complementation of the mutant strain with the wild-type expI gene in trans successfully restored AHL and PCWDE production as well as virulence. Transmission electron microscopy and in vitro motility assays demonstrated hyperpiliation and loss of flagella and swimming motility in the mutant strain compared with the wild-type Pcb1692. Furthermore, we noted that, in the early stages of infection, Pcb1692 wild-type cells had intact flagella which were shed at the later stages of infection. Confocal laser microscopy of PcbΔexpI-inoculated plants showed that the mutant strain tended to aggregate in intercellular spaces, but was unable to transit to xylem tissue. On the contrary, the wild-type strain was often observed forming aggregates within xylem tissue of potato stems. Gene expression analyses confirmed that flagella are part of the quorum sensing regulon, whereas fimbriae and pili appear to be negatively regulated by quorum sensing. The relative expression levels of other important putative virulence genes, such as those encoding different groups of PCWDEs, were down-regulated in the mutant compared with the wild-type strain. © 2016 BSPP and John Wiley & Sons Ltd.

  18. Appositional bone formation in marginal defects at implants.

    Science.gov (United States)

    Botticelli, Daniele; Berglundh, Tord; Buser, Daniel; Lindhe, Jan

    2003-02-01

    In a previous experiment, it was demonstrated that a wide marginal defect around an implant can heal with a high degree of osseointegration. The present experiment was performed to evaluate the degree and quality of de novo bone formation and osseointegration in marginal defects adjacent to submerged titanium implants. All mandibular premolars and 1st molars were extracted in four Labrador dogs. Four experimental sites were identified in the right side of the mandible. In two sites, custom-made implants with a sandblasted, large grit, acid-etched (SLA) surface were installed without further ostectomy (control sites). In the two remaining sites (test sites), a specially designed step drill was used to widen the marginal 5 mm of the canal. A barrier membrane was used to cover the implants in the defect sites. All implants were submerged. One month later, an identical procedure, including site preparation and implant installation, was performed in the left side of the mandible. Two months following the first implant installation procedure, biopsies were collected and prepared for sectioning. Ostectomy and implant installation in the control location resulted in a series of bone tissue alterations which eventually allowed newly formed bone to establish contact with the SLA surface. The marginal defect lateral to the implant in the test locations gradually became filled with newly formed bone. De novo bone formation started within the walls of the surgically prepared defect. Bone-to-implant contact was first established in the apical portion of the gap. This new bone tissue was in the coronal direction continuous with a dense, non-mineralized 'implant attached' soft tissue which, over time, also became mineralized to increase the height of the zone of bone-to-implant contact. The results suggest that healing of a wide marginal defect around an implant is characterized by appositional bone growth from the lateral and apical bone walls of the defect.

  19. Novel class of collector in electrospinning device for the fabrication of 3D nanofibrous structure for large defect load-bearing tissue engineering application.

    Science.gov (United States)

    Hejazi, Fatemeh; Mirzadeh, Hamid; Contessi, Nicola; Tanzi, Maria Cristina; Faré, Silvia

    2017-05-01

    Adequate porosity, appropriate pore size, and 3D-thick shape are crucial parameters in the design of scaffolds, as they should provide the right space for cell adhesion, spreading, migration, and growth. In this work, a novel design for fabricating a 3D nanostructured scaffold by electrospinning was taken into account. Helical spring-shaped collector was purposely designed and used for electrospinning PCL fibers. Improved morphological properties and more uniform diameter distribution of collected nanofibers on the turns of helical spring-shaped collector are confirmed by SEM analysis. SEM images elaboration showed 3D pores with average diameter of 4 and 5.5 micrometer in x-y plane and z-direction, respectively. Prepared 3D scaffold possessed 99.98% porosity which led to the increased water uptake behavior in PBS at 37°C up to 10 days, and higher degradation rate compared to 2D flat structure. Uniaxial compression test on 3D scaffolds revealed an elastic modulus of 7 MPa and a stiffness of 10 2 MPa, together with very low hysteresis area and residual strain. In vitro cytocompatibility test with MG-63 osteoblast-like cells using AlamarBlue ™ colorimetric assay, indicated a continuous increase in cell viability for the 3D structure over the test duration. SEM observation showed enhanced cells spreading and diffusion into the underneath layers for 3D scaffold. Accelerated calcium deposition in 3D substrate was confirmed by EDX analysis. Obtained morphological, physical, and mechanical properties together with in vitro cytocompatibility results, suggest this novel technique as a proper method for the fabrication of 3D nanofibrous scaffolds for the regeneration of critical-size load bearing defects. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1535-1548, 2017. © 2017 Wiley Periodicals, Inc.

  20. Embedded defects

    International Nuclear Information System (INIS)

    Barriola, M.; Vachaspati, T.; Bucher, M.

    1994-01-01

    We give a prescription for embedding classical solutions and, in particular, topological defects in field theories which are invariant under symmetry groups that are not necessarily simple. After providing examples of embedded defects in field theories based on simple groups, we consider the electroweak model and show that it contains the Z string and a one-parameter family of strings called the W(α) string. It is argued that although the members of this family are gauge equivalent when considered in isolation, each member becomes physically distinct when multistring configurations are considered. We then turn to the issue of stability of embedded defects and demonstrate the instability of a large class of such solutions in the absence of bound states or condensates. The Z string is shown to be unstable for all values of the Higgs boson mass when θ W =π/4. W strings are also shown to be unstable for a large range of parameters. Embedded monopoles suffer from the Brandt-Neri-Coleman instability. Finally, we connect the electroweak string solutions to the sphaleron

  1. Topological defects in epithelia govern cell death and extrusion

    Science.gov (United States)

    Saw, Thuan Beng; Doostmohammadi, Amin; Nier, Vincent; Kocgozlu, Leyla; Thampi, Sumesh; Toyama, Yusuke; Marcq, Philippe; Lim, Chwee Teck; Yeomans, Julia M.; Ladoux, Benoit

    2017-04-01

    Epithelial tissues (epithelia) remove excess cells through extrusion, preventing the accumulation of unnecessary or pathological cells. The extrusion process can be triggered by apoptotic signalling, oncogenic transformation and overcrowding of cells. Despite the important linkage of cell extrusion to developmental, homeostatic and pathological processes such as cancer metastasis, its underlying mechanism and connections to the intrinsic mechanics of the epithelium are largely unexplored. We approach this problem by modelling the epithelium as an active nematic liquid crystal (that has a long range directional order), and comparing numerical simulations to strain rate and stress measurements within monolayers of MDCK (Madin Darby canine kidney) cells. Here we show that apoptotic cell extrusion is provoked by singularities in cell alignments in the form of comet-shaped topological defects. We find a universal correlation between extrusion sites and positions of nematic defects in the cell orientation field in different epithelium types. The results confirm the active nematic nature of epithelia, and demonstrate that defect-induced isotropic stresses are the primary precursors of mechanotransductive responses in cells, including YAP (Yes-associated protein) transcription factor activity, caspase-3-mediated cell death, and extrusions. Importantly, the defect-driven extrusion mechanism depends on intercellular junctions, because the weakening of cell-cell interactions in an α-catenin knockdown monolayer reduces the defect size and increases both the number of defects and extrusion rates, as is also predicted by our model. We further demonstrate the ability to control extrusion hotspots by geometrically inducing defects through microcontact printing of patterned monolayers. On the basis of these results, we propose a mechanism for apoptotic cell extrusion: spontaneously formed topological defects in epithelia govern cell fate. This will be important in predicting

  2. ACC oxidase genes expressed in the wood-forming tissues of loblolly pine (Pinus taeda L.) include a pair of nearly identical paralogs (NIPs).

    Science.gov (United States)

    Yuan, S; Wang, Y; Dean, J F D

    2010-03-15

    1-Aminocyclopropane-1-carboxylate (ACC) oxidase catalyzes the final reaction of the ethylene biosynthetic pathway, converting the unusual cyclic amino acid, ACC, into ethylene. Past studies have shown a possible link between ethylene and compression wood formation in conifers, but the relationship has received no more than modest study at the gene expression level. In this study, a cDNA clone encoding a putative ACC oxidase, PtACO1, was isolated from a cDNA library produced using mRNA from lignifying xylem of loblolly pine (Pinus taeda) trunk wood. The cDNA clone comprised an open reading frame of 1461 bp encoding a protein of 333 amino acids. Using PCR amplification techniques, a genomic clone corresponding to PtACO1 was isolated and shown to contain three introns with typical GT/AG boundaries defining the splice junctions. The PtACO1 gene product shared 70% identity with an ACC oxidase from European white birch (Betula pendula), and phylogenetic analyses clearly placed the gene product in the ACC oxidase cluster of the Arabidopsis thaliana 2-oxoglutarate-dependent dioxygenase superfamily tree. The PtACO1 sequence was used to identify additional ACC oxidase clones from loblolly pine root cDNA libraries characterized as part of an expressed sequence tag (EST) discovery project. The PtACO1 sequence was also used to recover additional paralogous sequences from genomic DNA, one of which (PtACO2) turned out to be >98% identical to PtACO1 in the nucleotide coding sequence, leading to its classification as a "nearly identical paralog" (NIP). Quantitative PCR analyses showed that the expression level of PtACO1-like transcripts varied in different tissues, as well as in response to hormonal treatments and bending. Possible roles for PtACO1 in compression wood formation in loblolly pine and the discovery of its NIP are discussed in light of these results. 2009 Elsevier B.V. All rights reserved.

  3. Defective glucose and lipid metabolism in human immunodeficiency virus-infected patients with lipodystrophy involve liver, muscle tissue and pancreatic beta-cells

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Andersen, Ove; Dela, Flemming

    2005-01-01

    of glucose metabolism, lipid metabolism and beta-cell function in lipodystrophic HIV-infected patients. METHODS: [3-3H]glucose was applied during euglycaemic hyperinsulinaemic clamps in association with indirect calorimetry in 43 normoglycaemic HIV-infected patients (18 lipodystrophic patients on HAART (LIPO....... CONCLUSION: Our data suggest that normoglycaemic lipodystrophic HIV-infected patients display impaired glucose and lipid metabolism in multiple pathways involving liver, muscle tissue and beta-cell function.......OBJECTIVES: Lipodystrophy and insulin resistance are prevalent among human immunodeficiency virus (HIV)-infected patients on combined antiretroviral therapy (HAART). Aiming to provide a detailed description of the metabolic adverse effects of HIV-lipodystrophy, we investigated several aspects...

  4. Kappa-splints application for the treatment of pathological dental hard tissues abrasion in combination with dentition defects and dentition deformations

    Directory of Open Access Journals (Sweden)

    Svitlana Petrishin

    2017-03-01

    2. After studying the movements of conventional hinge axis in articulate heads of TMJ with the help of condylograph «Cadiax Compact» and eliminating the symptoms of stress in masticatory muscles of the patients with occlusive disorders at pathological dental hard tissues abrasion, it is the gradual application of a kappa-splints set, made of hard transparent plates of Ercodent Ercodur material (Germany with a thickness of 1.0 to 5.0 mm, which allows prevention of further tooth wear, normalization of occlusive correlations of the jaws, separating a bite with optimum thickness throughout the dentition, thus the lower jaw takes a position at which the state of functional equilibrium of the entire dentition is restored.

  5. Defective glucose and lipid metabolism in human immunodeficiency virus-infected patients with lipodystrophy involve liver, muscle tissue and pancreatic beta-cells

    DEFF Research Database (Denmark)

    Haugaard, Steen B; Andersen, Ove; Dela, Flemming

    2005-01-01

    OBJECTIVES: Lipodystrophy and insulin resistance are prevalent among human immunodeficiency virus (HIV)-infected patients on combined antiretroviral therapy (HAART). Aiming to provide a detailed description of the metabolic adverse effects of HIV-lipodystrophy, we investigated several aspects...... of glucose metabolism, lipid metabolism and beta-cell function in lipodystrophic HIV-infected patients. METHODS: [3-3H]glucose was applied during euglycaemic hyperinsulinaemic clamps in association with indirect calorimetry in 43 normoglycaemic HIV-infected patients (18 lipodystrophic patients on HAART (LIPO....... CONCLUSION: Our data suggest that normoglycaemic lipodystrophic HIV-infected patients display impaired glucose and lipid metabolism in multiple pathways involving liver, muscle tissue and beta-cell function....

  6. Reconstructions of eyelid defects

    Directory of Open Access Journals (Sweden)

    Nirmala Subramanian

    2011-01-01

    Full Text Available Eyelids are the protective mechanism of the eyes. The upper and lower eyelids have been formed for their specific functions by Nature. The eyelid defects are encountered in congenital anomalies, trauma, and postexcision for neoplasm. The reconstructions should be based on both functional and cosmetic aspects. The knowledge of the basic anatomy of the lids is a must. There are different techniques for reconstructing the upper eyelid, lower eyelid, and medial and lateral canthal areas. Many a times, the defects involve more than one area. For the reconstruction of the lid, the lining should be similar to the conjunctiva, a cover by skin and the middle layer to give firmness and support. It is important to understand the availability of various tissues for reconstruction. One layer should have the vascularity to support the other layer which can be a graft. A proper plan and execution of it is very important.

  7. Prosthetic rehabilitation of large mid-facial defect with magnet-retained silicone prosthesis

    Directory of Open Access Journals (Sweden)

    Kirti Jajoo Shrivastava

    2015-01-01

    Full Text Available Rehabilitation of maxillofacial defect patients is a challenging task. The most common prosthetic treatment problem with such patients is, getting adequate retention, stability, and support. In cases of large maxillofacial defect, movement of the prosthesis is inevitable. The primary objectives in rehabilitating the maxillofacial defect patients are to restore the function of mastication, deglutition, speech, and to achieve normal orofacial appearance. This clinical report describes maxillofacial prosthetic rehabilitation of large midfacial defect including orbit along with its contents, zygoma and soft tissues including half of the nose, cheeks, upper lip of left side, accompanying postsurgical microstomia and orofacial communication, which resulted from severe fungal infection mucormycosis. The defect in this case was restored with magnet retained two piece maxillofacial prosthesis having hollow acrylic resin framework and an overlying silicone facial prosthesis. The retention of prosthesis was further enhanced with the use of spectacles. This type of combination prosthesis enhanced the cosmesis and functional acceptability of prosthesis.

  8. BWR SFAT, gross-defect verification of spent BWR fuel. Final report on Task FIN A563 on the Finnish Support Programme to IAEA Safeguards including BWR SFAT User Manual

    International Nuclear Information System (INIS)

    Tarvainen, M.; Paakkunainen, M.; Tiitta, A.; Sarparanta, K.

    1994-04-01

    A measurement instrument called Spent Fuel Attribute Tester, SFAT, has been designed, fabricated and taken into use by the IAEA in gross defect verification of spent BWR fuel assemblies. The equipment consists of an underwater measurement head connected with cables to a control unit on the bridge of the fuel handling machine as well as to a PMCA for measurement of the gamma spectra. The BWR SFAT is optimized for the AFR interim storage, TVO KPA-STORE, of the TVO Power Company in Olkiluoto, Finland. It has a shape and it is moved like a fuel assembly using the fuel handling machine. No fuel movements are needed. Spent fuel specific radiation from the fission product 137 Cs at the gamma-ray energy of 662 keV is detected above the assemblies in the storage rack using a NaI(Tl) detector. In the design and in licensing the requirements of the IAEA, operator and the safety authority have been taken into account. The BWR SFAT allows modifications for other LWR fuel types with minor changes. The work has been carried out under the task FIN A 563 of the Finnish Support Programme to IAEA Safeguards. (orig.) (9 refs., 22 figs.)

  9. Multipaddled anterolateral thigh chimeric flap for reconstruction of complex defects in head and neck.

    Directory of Open Access Journals (Sweden)

    Canhua Jiang

    Full Text Available The anterolateral thigh flap has been the workhouse flap for coverage of soft-tissue defects in head and neck for decades. However, the reconstruction of multiple and complex soft-tissue defects in head and neck with multipaddled anterolateral thigh chimeric flaps is still a challenge for reconstructive surgeries. Here, a clinical series of 12 cases is reported in which multipaddled anterolateral thigh chimeric flaps were used for complex soft-tissue defects with several separately anatomic locations in head and neck. Of the 12 cases, 7 patients presented with trismus were diagnosed as advanced buccal cancer with oral submucous fibrosis, 2 tongue cancer cases were found accompanied with multiple oral mucosa lesions or buccal cancer, and 3 were hypopharyngeal cancer with anterior neck skin invaded. All soft-tissue defects were reconstructed by multipaddled anterolateral thigh chimeric flaps, including 9 tripaddled anterolateral thigh flaps and 3 bipaddled flaps. The mean length of skin paddle was 19.2 (range: 14-23 cm and the mean width was 4.9 (range: 2.5-7 cm. All flaps survived and all donor sites were closed primarily. After a mean follow-up time of 9.1 months, there were no problems with the donor or recipient sites. This study supports that the multipaddled anterolateral thigh chimeric flap is a reliable and good alternative for complex and multiple soft-tissue defects of the head and neck.

  10. Characterization of the structure and chemistry of defects in materials

    International Nuclear Information System (INIS)

    Larson, B.C.; Ruehle, M.; Seidman, D.N.

    1988-01-01

    Research programs, presented at the materials research symposium, on defects in materials are presented. Major areas include: point defects, defect aggregates, and ordering; defects in non-metals and semiconductors; atomic resolution imaging of defects; and gain boundaries, interfaces, and layered materials. Individual projects are processed separately for the data bases

  11. Use of autologous platelet - Rich plasma in the treatment of intrabony defects

    Directory of Open Access Journals (Sweden)

    Sharath K Shetty

    2009-01-01

    Treatment of intrabony defects by autologous PRP gel alone caused significant soft tissue clinical improvement as well as hard tissue defect fill as evidenced by SSD view in spiral computed tomography.

  12. Vascularized fibular transfer in longstanding and infected large bone defects.

    Science.gov (United States)

    Lê Thua, Trung-Hau; Pham, Dang-Nhat; Boeckx, Willy; De Mey, Albert

    2014-03-01

    The reconstruction of large bone defects in the infectious environment is still a big challenge for limb salvage because of disturbance in bacterial flora, bacterial resistance and limitation of blood supply at scarred tissue. This retrospective study was to evaluate long-term outcomes in patients who were performed vascularized fibular transfers for treatment of large bone defects in the infectious environment. The review included 26 patients with an average age of 27 years old. Bone defects were located at the arm in 1 patient, the forearm in 2 patients, the thigh in 6 patients and the leg in 17 patients. The cause of the bone defects included high-energy trauma in 14 cases, chronic osteomyelitis in 7 cases, infected non-union in 5 cases. All patients had had several previous operative procedures. The average length of fibular vascularized graft was 16.6 cm (range, 10-22 cm), and the average size of the associated fasciocutaneous component in 16 patients was 3.6 x 8.5 cm. Three patients had partial necrosis of skin paddle. Three patients, who were stabilized by screw and external fixator, had an infection at the distal part of the fibular graft and pin tracts. 25 fibular grafts (96%) showed complete bone union. This review has showed that the vascularized fibular transfer can be effective for management of large segmental bone defects in the infectious environment.

  13. Fashioning reversed axial pattern forearm tissues in different challenging conditions of the forearm territory as a reliable substitute for free tissue transfer.

    Science.gov (United States)

    El-Shazly, M

    2012-01-01

    Traumatic tissue defects, chronic ulcerations, burn contractures and post-oncological excisions are the main problems affecting the hand and forearm areas. This work addresses the question of whether reversed axial island flaps from the forearm area could be applicable to any form of soft tissue defects in the territory of the forearm, and whether they could be considered reliable substitutes for free tissue transfer. Thirteen patients who sought surgical treatment for soft tissue defects of the hand, wrist, and distal forearm regions were included in this evaluation report. The patients complained of four different etiologies, and their resultant tissue defects were managed by reversed radial forearm flap in eight cases and by the ulnar variety of the reversed forearm flap in another five cases. Selection of the flap option depended on the site of the pathology, size and thickness of the resultant defect, special needs of the defect, vascular limitations, and the like-tissue reconstruction objective. All flaps survived well with no complications. Both donor and recipient sites healed successfully. The selected flaps were ideal in their specific application. Harvesting reversed forearm flaps does not require high surgical skills or special equipment, venous congestion is less significant than with free flaps, and the patients do not need intensive immediate postoperative care and supervision. This is an easy and reliable technique requiring short operating time, and initiation of early physiotherapy is permitted, making forearm flaps reliable substitutes for free flap applications with all the associated complications.

  14. Extrinsic point defects in aluminum antimonide

    OpenAIRE

    Erhart, Paul; Åberg, Daniel; Lordi, Vincenzo

    2010-01-01

    We investigate thermodynamic and electronic properties of group IV (C, Si, Ge, Sn) and group VI (O, S, Se, Te) impurities as well as P and H in aluminum antimonide (AlSb) using first-principles calculations. To this end, we compute the formation energies of a broad range of possible defect configurations including defect complexes with the most important intrinsic defects. We also obtain relative scattering cross strengths for these defects to determine their impact on charge carrier mobility...

  15. Neural Tube Defects

    Science.gov (United States)

    Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the ... that she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In ...

  16. The Significance of Immunohistochemical Staining, Including that for Glucose Transporter Protein Isoform 1, as Related to the Clinical and Angiographic Features of Adult Soft-Tissue Hemangioma and Arteriovenous Malformation in the Head and Neck

    International Nuclear Information System (INIS)

    Lee, Ha Young; Kim, Seon Mi; Choi, Jin Woo

    2009-01-01

    Glucose transporter protein isoform 1 (GLUT1) has been introduced to diagnose the hemangiomas of infancy. We investigated the usefulness of several immunohistochemical markers, including GLUT1, as related with the clinical and radiologic findings for making the diagnosis of adult subcutaneous vascular lesions in the head and neck. Materials and Methods: The 24 patients who underwent operations for soft tissue vascular lesion during the previous 7 years were included in this study. We analyzed the angiographic data, the clinical data and the immunohistochemical study results, including the GLUT1, S-100 protein and Movat pentichrome staining. Results: Twenty-two patients were confirmed to have arteriovenous malformation (AVM) and two hemangiomas, respectively. The number of lesions with positive Movat pentichrome, S-100 and GLUT1 staining in the patients with AVM and those patients with hemangioma were 22/22, 20/22 and 0/22, and 0/2, 0/2 and 0/2, respectively. For the 22 patients with AVMs, eight had a soft tissue vascular lesion at birth, 13 had cutaneous change and 15 had a change of the size of the lesion. For the 2 patients with one hemangioma each, neither patient had a soft tissue vascular lesion at birth, and both patients had cutaneous change and a change of the size of the lesion. The angiograms revealed a focal hypervascular mass (19/24) or diffuse staining (5/24) without showing significant features for making the definitive differential diagnosis. Our study revealed that none of the patients with AVM or hemangioma had GLUT1 positivity, and an arteriovenous malformation was more common than the adult-type hemangioma

  17. Photochemical tissue bonding

    Science.gov (United States)

    Redmond, Robert W [Brookline, MA; Kochevar, Irene E [Charlestown, MA

    2012-01-10

    Photochemical tissue bonding methods include the application of a photosensitizer to a tissue and/or tissue graft, followed by irradiation with electromagnetic energy to produce a tissue seal. The methods are useful for tissue adhesion, such as in wound closure, tissue grafting, skin grafting, musculoskeletal tissue repair, ligament or tendon repair and corneal repair.

  18. Serine biosynthesis and transport defects.

    Science.gov (United States)

    El-Hattab, Ayman W

    2016-07-01

    l-serine is a non-essential amino acid that is biosynthesized via the enzymes phosphoglycerate dehydrogenase (PGDH), phosphoserine aminotransferase (PSAT), and phosphoserine phosphatase (PSP). Besides its role in protein synthesis, l-serine is a potent neurotrophic factor and a precursor of a number of essential compounds including phosphatidylserine, sphingomyelin, glycine, and d-serine. Serine biosynthesis defects result from impairments of PGDH, PSAT, or PSP leading to systemic serine deficiency. Serine biosynthesis defects present in a broad phenotypic spectrum that includes, at the severe end, Neu-Laxova syndrome, a lethal multiple congenital anomaly disease, intermediately, infantile serine biosynthesis defects with severe neurological manifestations and growth deficiency, and at the mild end, the childhood disease with intellectual disability. A serine transport defect resulting from deficiency of the ASCT1, the main transporter for serine in the central nervous system, has been recently described in children with neurological manifestations that overlap with those observed in serine biosynthesis defects. l-serine therapy may be beneficial in preventing or ameliorating symptoms in serine biosynthesis and transport defects, if started before neurological damage occurs. Herein, we review serine metabolism and transport, the clinical, biochemical, and molecular aspects of serine biosynthesis and transport defects, the mechanisms of these diseases, and the potential role of serine therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Is Three-Dimensional Echocardiography Useful in Evaluation of Atrial Septal Defects?

    Directory of Open Access Journals (Sweden)

    Charles German

    2015-06-01

    Full Text Available Of all birth defects, Congenital Heart Disease (CHD remains the most prevalent. These malformations are largely multifactorial with both environmental and genetic components, but known chromosomal abnormalities and mutations of single genes account for less than 10% of all cardiac defects (1. They affect approximately 6 to 13 newborns per 1000 live births (2 and are made up of 5 major Atrial Septal Defects (ASDs, including primum and secundum type defects, sinus venosus and coronary sinus defects, and Patent Foramen Ovale (PFO. However, there is debate within the medical community regarding inclusion of PFOs and coronary sinus defects within the realm of CHD. PFOs do not have absent septal tissue, and coronary sinus defects, or unroofed coronary sinus, represent an abnormal communication between the superior portion of the coronary sinus and the neighboring left atrium. Regardless, these anomalies can go undetected at birth, particularly if asymptomatic. Though some defects may be innocuous at birth, the continued shunting of blood between the atria can lead to pulmonary hypertension, heart failure, and even death. Thus, finding an accurate and reliable means of diagnosis via echocardiography is necessary in establishing the optimal treatment and ultimately improving patient mortality.

  20. Defect forces, defect couples and path integrals in fracture mechanics

    International Nuclear Information System (INIS)

    Roche, R.L.

    1979-07-01

    In this work, it is shown that the path integrals can be introduced without any reference to the material behavior. The method is based on the definition in a continuous medium of a set of vectors and couples having the dimension of a force or a moment. More precisely, definitions are given of volume defect forces, surface defect forces, volume defect couples, and surface defect couples. This is done with the help of the stress working variation of a particule moving through the solid. The most important result is: the resultant of all the defect forces included in a volume V is the J integral on the surface surrounding V and the moment resultant is the L integral. So these integrals are defined without any assumption on the material constitutive equation. Another result is the material form of the virtual work principle - defect forces are acting like conventional forces in the conventional principles of virtual work. This lead to the introduction of the energy momentum tensor and of the associated couple stress. Application of this method is made to fracture mechanics in studying the defect forces distribution around a crack [fr

  1. Magnetoencephalography signals are influenced by skull defects.

    Science.gov (United States)

    Lau, S; Flemming, L; Haueisen, J

    2014-08-01

    Magnetoencephalography (MEG) signals had previously been hypothesized to have negligible sensitivity to skull defects. The objective is to experimentally investigate the influence of conducting skull defects on MEG and EEG signals. A miniaturized electric dipole was implanted in vivo into rabbit brains. Simultaneous recording using 64-channel EEG and 16-channel MEG was conducted, first above the intact skull and then above a skull defect. Skull defects were filled with agar gels, which had been formulated to have tissue-like homogeneous conductivities. The dipole was moved beneath the skull defects, and measurements were taken at regularly spaced points. The EEG signal amplitude increased 2-10 times, whereas the MEG signal amplitude reduced by as much as 20%. The EEG signal amplitude deviated more when the source was under the edge of the defect, whereas the MEG signal amplitude deviated more when the source was central under the defect. The change in MEG field-map topography (relative difference measure, RDM(∗)=0.15) was geometrically related to the skull defect edge. MEG and EEG signals can be substantially affected by skull defects. MEG source modeling requires realistic volume conductor head models that incorporate skull defects. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  2. Incorporation by host tissue of two biomaterials used as repair of defects produced in abdominal wall of rats Incorporação por tecido do hospedeiro de dois biomateriais usados como reparo de defeitos produzido em parede abdominal de ratos

    Directory of Open Access Journals (Sweden)

    Suyiene Cordeiro Falcão

    2008-02-01

    Full Text Available PURPOSE: Biomaterials may be used as treatment of great abdominal wall defects to avoid tension during repair. In the present research we intended to investigate incorporation type by host tissue of membranes of microbial cellulose (MC, produced by the bacteria Zoogloea sp., and of polytetrafluoroethylene (ePTFE in abdominal wall defects of rats. METHODS: Sixty male rats Wistar, anesthetized by ketamine (5mg/100g and xylazine (2mg/100g, were submitted to a rectangular excision (2x3cm of the abdominal wall, including fascia, muscles and peritoneum and further treated with implants of microbial cellulose (MC Group - 30 animals or expanded polytetrafluoroethylene ( ePTFE Group- 30 animals. Each group was subdivided in 14th DPO, 28th DPO and 60th DPO Subgroups. RESULTS: Incorporation of biomaterials was observed by wrapping and infiltration by host tissue. It has been found that wrapping associated to infiltration of host connective tissue in implants of ePTFE were present in 100% of the observed samples, and this may be responsible for increase resistance to traction. Inversely, wrapping without host tissue infiltration was seen in 100% of examined specimens of MC implants. CONCLUSION: Wrapping and host tissue infiltration is seen only in ePTFE implants.OBJETIVO: Biomateriais podem ser usados como tratamento de grandes defeitos da parede abdominal para evitar tensão durante reparo. Na presente pesquisa pretendeu-se investigar o tipo de incorporação pelo tecido do hospedeiro de membranas de celulose microbiana (CM, produzidas pela bactérias Zoogloea sp., e de politetrafluoretileno (PTFEe em defeitos da parede abdominal de ratos. MÉTODOS: Sessenta ratos machos Wistar, anestesiados através de cetamina (5mg/100g e xilazina (2mg/100g, foram submetidos a uma excisão retangular (2x3cm da parede abdominal, incluindo fascia, músculos e peritoneum e posteriormente tratadas com implantes de celulose microbiana (Groupo CM - 30 animais ou

  3. Tissue engineering

    CERN Document Server

    Fisher, John P; Bronzino, Joseph D

    2007-01-01

    Increasingly viewed as the future of medicine, the field of tissue engineering is still in its infancy. As evidenced in both the scientific and popular press, there exists considerable excitement surrounding the strategy of regenerative medicine. To achieve its highest potential, a series of technological advances must be made. Putting the numerous breakthroughs made in this field into a broad context, Tissue Engineering disseminates current thinking on the development of engineered tissues. Divided into three sections, the book covers the fundamentals of tissue engineering, enabling technologies, and tissue engineering applications. It examines the properties of stem cells, primary cells, growth factors, and extracellular matrix as well as their impact on the development of tissue engineered devices. Contributions focus on those strategies typically incorporated into tissue engineered devices or utilized in their development, including scaffolds, nanocomposites, bioreactors, drug delivery systems, and gene t...

  4. Hair defects in Hoxc13 mutant mice.

    Science.gov (United States)

    Godwin, A R; Capecchi, M R

    1999-12-01

    Hox genes encode transcription factors that are important during normal embryonic development of diverse organisms including vertebrates. In mammals, Hox genes are responsible for conferring regional identity in embryonic tissues, including the limb bud, the neural tube, the presomitic mesoderm and the intestinal tract. Recent studies have demonstrated expression of Hox genes in skin and hair follicles, suggesting potential functions for these genes in epidermal appendages. These studies are reviewed here with emphasis on Hoxc13, as Hoxc13 mutants are the first Hox mutants to demonstrate overt hair defects. In addition, because Hoxc13 does not show regionally restricted expression in the skin, as demonstrated for other Hox genes, the potentially different roles of Hoxc13 versus other Hox genes in the skin are discussed.

  5. Mesenchymal Stem Cells for Treating Articular Cartilage Defects and Osteoarthritis.

    Science.gov (United States)

    Wang, Yu; Yuan, Mei; Guo, Quan-yi; Lu, Shi-bi; Peng, Jiang

    2015-01-01

    Articular cartilage damage and osteoarthritis are the most common joint diseases. Joints are prone to damage caused by sports injuries or aging, and such damage regularly progresses to more serious joint disorders, including osteoarthritis, which is a degenerative disease characterized by the thinning and eventual wearing out of articular cartilage, ultimately leading to joint destruction. Osteoarthritis affects millions of people worldwide. Current approaches to repair of articular cartilage damage include mosaicplasty, microfracture, and injection of autologous chondrocytes. These treatments relieve pain and improve joint function, but the long-term results are unsatisfactory. The long-term success of cartilage repair depends on development of regenerative methodologies that restore articular cartilage to a near-native state. Two promising approaches are (i) implantation of engineered constructs of mesenchymal stem cell (MSC)-seeded scaffolds, and (ii) delivery of an appropriate population of MSCs by direct intra-articular injection. MSCs may be used as trophic producers of bioactive factors initiating regenerative activities in a defective joint. Current challenges in MSC therapy are the need to overcome current limitations in cartilage cell purity and to in vitro engineer tissue structures exhibiting the required biomechanical properties. This review outlines the current status of MSCs used in cartilage tissue engineering and in cell therapy seeking to repair articular cartilage defects and related problems. MSC-based technologies show promise when used to repair cartilage defects in joints.

  6. Dural sinus filling defect: intrasigmoid encephalocele

    Science.gov (United States)

    Karatag, Ozan; Cosar, Murat; Kizildag, Betul; Sen, Halil Murat

    2013-01-01

    Filling defects of dural venous sinuses are considered to be a challenging problem especially in case of symptomatic patients. Many lesions have to be ruled out such as sinus thrombosis, arachnoid granulations and tumours. Encephalocele into dural sinus is also a rare cause of these filling defects of dural sinuses. Here, we report an extremely rare case with spontaneous occult invagination of temporal brain tissue into the left sigmoid sinus and accompanying cerebellar ectopia. PMID:24311424

  7. A composite model including visfatin, tissue polypeptide-specific antigen, hyaluronic acid, and hematological variables for the diagnosis of moderate-to-severe fibrosis in nonalcoholic fatty liver disease: a preliminary study.

    Science.gov (United States)

    Chwist, Alina; Hartleb, Marek; Lekstan, Andrzej; Kukla, Michał; Gutkowski, Krzysztof; Kajor, Maciej

    2014-01-01

    Histopathological risk factors for end-stage liver failure in patients with nonalcoholic fatty liver disease (NAFLD) include nonalcoholic steatohepatitis (NASH) and advanced liver fibrosis. There is a need for noninvasive diagnostic methods for these 2 conditions. The aim of this study was to investigate new laboratory variables with a predictive potential to detect advanced fibrosis (stages 2 and 3) in NAFLD. The study involved 70 patients with histologically proven NAFLD of varied severity. Additional laboratory variables included zonulin, haptoglobin, visfatin, adiponectin, leptin, tissue polypeptide-specific antigen (TPSA), hyaluronic acid, and interleukin 6. Patients with NASH (NAFLD activity score of ≥5) had significantly higher HOMA-IR values and serum levels of visfatin, haptoglobin, and zonulin as compared with those without NASH on histological examination. Advanced fibrosis was found in 16 patients (22.9%) and the risk factors associated with its prevalence were age, the ratio of erythrocyte count to red blood cell distribution width, platelet count, and serum levels of visfatin and TPSA. Based on these variables, we constructed a scoring system that differentiated between NAFLD patients with and without advanced fibrosis with a sensitivity of 75% and specificity of 100% (area under the receiver operating characteristic curve, 0.93). The scoring system based on the above variables allows to predict advanced fibrosis with high sensitivity and specificity. However, its clinical utility should be verified in further studies involving a larger number of patients.

  8. Optimizing reconstruction of oncologic sternectomy defects based on surgical outcomes.

    Science.gov (United States)

    Butterworth, James A; Garvey, Patrick B; Baumann, Donald P; Zhang, Hong; Rice, David C; Butler, Charles E

    2013-08-01

    The optimal strategy for oncologic sternectomy reconstruction has not been well characterized. We hypothesized that the major factors driving the reconstructive strategy for oncologic sternectomy include the need for skin replacement, extent of the bony sternectomy defect, and status of the internal mammary vessels. We reviewed consecutive oncologic sternectomy reconstructions performed at The University of Texas MD Anderson Cancer Center during a 10-year period. Regression models analyzed associations between patient, defect, and treatment factors and outcomes to identify patient and treatment selection criteria. We developed a generalized management algorithm based on these data. Forty-nine consecutive patients underwent oncologic sternectomy reconstruction (mean follow-up 18 ± 23 months). More sternectomies were partial (74%) rather than total/subtotal (26%). Most defects (n = 40 [82%]) required skeletal reconstruction. Pectoralis muscle flaps were most commonly used for sternectomies with intact overlying skin (64%) and infrequently used when a presternal skin defect was present (36%; p = 0.06). Free flaps were more often used for total/subtotal vs partial sternectomy defects (75% vs 25%, respectively; p = 0.02). Complication rates for total/subtotal sternectomy and partial sternectomy were equivalent (46% vs 44%, respectively; p = 0.92). Despite more extensive sternal resections, total/subtotal sternectomies resulted in equivalent postoperative complications when combined with the appropriate soft-tissue reconstruction. Good surgical and oncologic outcomes can be achieved with defect-characteristic-matched reconstructive strategies for these complex oncologic sternectomy resections. Copyright © 2013 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  9. Additive manufacturing for in situ repair of osteochondral defects

    International Nuclear Information System (INIS)

    Cohen, Daniel L; Lipton, Jeffrey I; Bonassar, Lawrence J; Lipson, Hod

    2010-01-01

    Tissue engineering holds great promise for injury repair and replacement of defective body parts. While a number of techniques exist for creating living biological constructs in vitro, none have been demonstrated for in situ repair. Using novel geometric feedback-based approaches and through development of appropriate printing-material combinations, we demonstrate the in situ repair of both chondral and osteochondral defects that mimic naturally occurring pathologies. A calf femur was mounted in a custom jig and held within a robocasting-based additive manufacturing (AM) system. Two defects were induced: one a cartilage-only representation of a grade IV chondral lesion and the other a two-material bone and cartilage fracture of the femoral condyle. Alginate hydrogel was used for the repair of cartilage; a novel formulation of demineralized bone matrix was used for bone repair. Repair prints for both defects had mean surface errors less than 0.1 mm. For the chondral defect, 42.8 ± 2.6% of the surface points had errors that were within a clinically acceptable error range; however, with 1 mm path planning shift, an estimated ∼75% of surface points could likely fall within the benchmark envelope. For the osteochondral defect, 83.6 ± 2.7% of surface points had errors that were within clinically acceptable limits. In addition to implications for minimally invasive AM-based clinical treatments, these proof-of-concept prints are some of the only in situ demonstrations to-date, wherein the substrate geometry was unknown a priori. The work presented herein demonstrates in situ AM, suggests potential biomedical applications and also explores in situ-specific issues, including geometric feedback, material selection and novel path planning techniques.

  10. Characterization and evaluation of graphene oxide scaffold for periodontal wound healing of class II furcation defects in dog.

    Science.gov (United States)

    Kawamoto, Kohei; Miyaji, Hirofumi; Nishida, Erika; Miyata, Saori; Kato, Akihito; Tateyama, Akito; Furihata, Tomokazu; Shitomi, Kanako; Iwanaga, Toshihiko; Sugaya, Tsutomu

    2018-01-01

    The 3-dimensional scaffold plays a key role in volume and quality of repair tissue in periodontal tissue engineering therapy. We fabricated a novel 3D collagen scaffold containing carbon-based 2-dimensional layered material, named graphene oxide (GO). The aim of this study was to characterize and assess GO scaffold for periodontal tissue healing of class II furcation defects in dog. GO scaffolds were prepared by coating the surface of a 3D collagen sponge scaffold with GO dispersion. Scaffolds were characterized using cytotoxicity and tissue reactivity tests. In addition, GO scaffold was implanted into dog class II furcation defects and periodontal healing was investigated at 4 weeks postsurgery. GO scaffold exhibited low cytotoxicity and enhanced cellular ingrowth behavior and rat bone forming ability. In addition, GO scaffold stimulated healing of dog class II furcation defects. Periodontal attachment formation, including alveolar bone, periodontal ligament-like tissue, and cementum-like tissue, was significantly increased by GO scaffold implantation, compared with untreated scaffold. The results suggest that GO scaffold is biocompatible and possesses excellent bone and periodontal tissue formation ability. Therefore, GO scaffold would be beneficial for periodontal tissue engineering therapy.

  11. Soft tissue grafting to improve implant esthetics

    Directory of Open Access Journals (Sweden)

    Moawia M Kassab

    2010-09-01

    Full Text Available Moawia M KassabDivision of Periodontics, Marquette University, School of Dentistry, Milwaukee, WI, USAAbstract: Dental implants are becoming the treatment of choice to replace missing teeth, especially if the adjacent teeth are free of restorations. When minimal bone width is present, implant placement becomes a challenge and often resulting in recession and dehiscence around the implant that leads to subsequent gingival recession. To correct such defect, the author turned to soft tissue autografting and allografting to correct a buccal dehiscence around tooth #24 after a malpositioned implant placed by a different surgeon. A 25-year-old woman presented with the chief complaint of gingival recession and exposure of implant threads around tooth #24. The patient received three soft tissue grafting procedures to augment the gingival tissue. The first surgery included a connective tissue graft to increase the width of the keratinized gingival tissue. The second surgery included the use of autografting (connective tissue graft to coronally position the soft tissue and achieve implant coverage. The third and final surgery included the use of allografting material Alloderm to increase and mask the implant from showing through the gingiva. Healing period was uneventful for the patient. After three surgical procedures, it appears that soft tissue grafting has increased the width and height of the gingiva surrounding the implant. The accomplished thickness of gingival tissue appeared to mask the showing of implant threads through the gingival tissue and allowed for achieving the desired esthetic that the patient desired. The aim of the study is to present a clinical case with soft tissue grafting procedures.Keywords: case report, connective tissue, dental implants, allograft, coronally positioned flap

  12. MRI of fibrous cortical defect and non-ossifying fibroma

    Energy Technology Data Exchange (ETDEWEB)

    Mishima, Yoshiko; Aoki, Takatoshi; Watanabe, Hideyuki; Nakata, Hajime; Hashimoto, Hiroshi; Nakamura, Toshitaka [Univ. of Occupational and Environmental Health, Kitakyushu, Fukuoka (Japan). School of Medicine

    1999-02-01

    Fibrous cortical defect and non-ossifying fibroma are the benign fibrous lesions of bone commonly involving children. Their diagnosis is usually done with radiography, and MR examinations are rarely performed. We evaluated MRI findings of 11 lesions in 10 cases of fibrous cortical defect and non-ossifying fibroma. Signal intensity of the lesions was varied and large lesions (2 cm<) tended to show heterogeneous signal intensity on both T1-weighted and T2-weighted images corresponding to a mixture of components including fibrous tissue, hemosiderin and foam cells. MRI helps to delineate the extent of the involved bone and to assess the various histological components of the lesions. However, their diagnosis is basically made on the radiographic findings and the role of MRI is limited. (author)

  13. On holographic defect entropy

    Energy Technology Data Exchange (ETDEWEB)

    Estes, John [Blackett Laboratory, Imperial College,London SW7 2AZ (United Kingdom); Jensen, Kristan [Department of Physics and Astronomy, University of Victoria,Victoria, BC V8W 3P6 (Canada); C.N. Yang Institute for Theoretical Physics, SUNY Stony Brook,Stony Brook, NY 11794-3840 (United States); O’Bannon, Andy [Rudolf Peierls Centre for Theoretical Physics, University of Oxford,1 Keble Road, Oxford OX1 3NP (United Kingdom); Tsatis, Efstratios [8 Kotylaiou Street, Athens 11364 (Greece); Wrase, Timm [Stanford Institute for Theoretical Physics, Stanford University,Stanford, CA 94305 (United States)

    2014-05-19

    We study a number of (3+1)- and (2+1)-dimensional defect and boundary conformal field theories holographically dual to supergravity theories. In all cases the defects or boundaries are planar, and the defects are codimension-one. Using holography, we compute the entanglement entropy of a (hemi-)spherical region centered on the defect (boundary). We define defect and boundary entropies from the entanglement entropy by an appropriate background subtraction. For some (3+1)-dimensional theories we find evidence that the defect/boundary entropy changes monotonically under certain renormalization group flows triggered by operators localized at the defect or boundary. This provides evidence that the g-theorem of (1+1)-dimensional field theories generalizes to higher dimensions.

  14. On holographic defect entropy

    Science.gov (United States)

    Estes, John; Jensen, Kristan; O'Bannon, Andy; Tsatis, Efstratios; Wrase, Timm

    2014-05-01

    We study a number of (3 + 1)- and (2 + 1)-dimensional defect and boundary conformal field theories holographically dual to supergravity theories. In all cases the defects or boundaries are planar, and the defects are codimension-one. Using holography, we compute the entanglement entropy of a (hemi-)spherical region centered on the defect (boundary). We define defect and boundary entropies from the entanglement entropy by an appropriate background subtraction. For some (3 + 1)-dimensional theories we find evidence that the defect/boundary entropy changes monotonically under certain renormalization group flows triggered by operators localized at the defect or boundary. This provides evidence that the g-theorem of (1 + 1)-dimensional field theories generalizes to higher dimensions.

  15. Soft Tissue Sarcoma

    Science.gov (United States)

    ... muscles, tendons, fat, and blood vessels. Soft tissue sarcoma is a cancer of these soft tissues. There ... have certain genetic diseases. Doctors diagnose soft tissue sarcomas with a biopsy. Treatments include surgery to remove ...

  16. Perception of risk from automobile safety defects.

    Science.gov (United States)

    Slovic, P; MacGregor, D; Kraus, N N

    1987-10-01

    Descriptions of safety engineering defects of the kind that compel automobile manufacturers to initiate a recall campaign were evaluated by individuals on a set of risk characteristic scales that included overall vehicle riskiness, manufacturer's ability to anticipate the defect, importance for vehicle operation, severity of consequences and likelihood of compliance with a recall notice. A factor analysis of the risk characteristics indicated that judgments could be summarized in terms of two composite scales, one representing the uncontrollability of the damage the safety defect might cause and the other representing the foreseeability of the defect by the manufacturer. Motor vehicle defects were found to be highly diverse in terms of the perceived qualities of their risks. Location of individual defects within the factor space was closely associated with perceived riskiness, perceived likelihood of purchasing another car from the same manufacturer, perceived likelihood of compliance with a recall notice, and actual compliance rates.

  17. The efficacy of using 'biohapel' in the therapy of infrabony periodontal defects

    Directory of Open Access Journals (Sweden)

    Stevanović Momir

    2014-01-01

    Full Text Available Vertical type of the alveolar bone resorption causes formation of periodontal pockets of infrabony type. Presence of these kinds of defects, from the aspect of a plan of therapy and the therapy itself represents a serious problem. The aim of this research was to test the efficacy of tissue regeneration of periodontal infrabony defects after using a new material 'Biohapel'. This study included 16 patients, males and females, of the average age of 48.6, all of them suffering from clinically manifested periodontal disease. The inclusion criteria for the study was presence of at least two similar periodontal defects 5 mm deep at least, around the same mandibular posterior teeth, bilaterally. After conducting initial therapy, the defects were divided into 2 groups - experimental group (n=16 which was reconstructed with 'Biohapel' implant (one side of the mandible and control group (n=16, where standard surgical procedure was applied (other side of the mandible. The assessment of periodontal tissues conditions was verified, before and 6 months after the surgical procedure was performed, measuring periodontal pocket depth and the clinical attachment level. Statistically significant difference between experimental and control group was noticed (p<0.05, in regar to the tested parameters of periodontal regeneration. Use of' Biohapel' in therapy of infrabony periodontal defects indicates highly significant level of bone regeneration in comparison with the standard surgical procedure.

  18. Detection of Quiescent Infections with Multiple Elephant Endotheliotropic Herpesviruses (EEHVs), Including EEHV2, EEHV3, EEHV6, and EEHV7, within Lymphoid Lung Nodules or Lung and Spleen Tissue Samples from Five Asymptomatic Adult African Elephants.

    Science.gov (United States)

    Zong, Jian-Chao; Heaggans, Sarah Y; Long, Simon Y; Latimer, Erin M; Nofs, Sally A; Bronson, Ellen; Casares, Miguel; Fouraker, Michael D; Pearson, Virginia R; Richman, Laura K; Hayward, Gary S

    2015-12-30

    More than 80 cases of lethal hemorrhagic disease associated with elephant endotheliotropic herpesviruses (EEHVs) have been identified in young Asian elephants worldwide. Diagnostic PCR tests detected six types of EEHV in blood of elephants with acute disease, although EEHV1A is the predominant pathogenic type. Previously, the presence of herpesvirus virions within benign lung and skin nodules from healthy African elephants led to suggestions that African elephants may be the source of EEHV disease in Asian elephants. Here, we used direct PCR-based DNA sequencing to detect EEHV genomes in necropsy tissue from five healthy adult African elephants. Two large lung nodules collected from culled wild South African elephants contained high levels of either EEHV3 alone or both EEHV2 and EEHV3. Similarly, a euthanized U.S. elephant proved to harbor multiple EEHV types distributed nonuniformly across four small lung nodules, including high levels of EEHV6, lower levels of EEHV3 and EEHV2, and a new GC-rich branch type, EEHV7. Several of the same EEHV types were also detected in random lung and spleen samples from two other elephants. Sanger PCR DNA sequence data comprising 100 kb were obtained from a total of 15 different strains identified, with (except for a few hypervariable genes) the EEHV2, EEHV3, and EEHV6 strains all being closely related to known genotypes from cases of acute disease, whereas the seven loci (4.0 kb) obtained from EEHV7 averaged 18% divergence from their nearest relative, EEHV3. Overall, we conclude that these four EEHV species, but probably not EEHV1, occur commonly as quiescent infections in African elephants. Acute hemorrhagic disease characterized by high-level viremia due to infection by members of the Proboscivirus genus threatens the future breeding success of endangered Asian elephants worldwide. Although the genomes of six EEHV types from acute cases have been partially or fully characterized, lethal disease predominantly involves a variety

  19. Hard tissue compatibility of natural hydroxyapatite/chitosan composite

    International Nuclear Information System (INIS)

    Tang Xiaojun; Gui Lai; Lue Xiaoying

    2008-01-01

    The natural hydroxyapatite/chitosan (NHC) composite is a new synthesized material. The aim of this experiment was to assess the bone tissue compatibility of this NHC composite in vivo. Twenty-four healthy New Zealand rabbits were included in this study. Of those, 20 were used as the experimental group and four as the control group. In the experimental group, animals receive a cranium defect procedure and NHC composite repair. In the control group, animals underwent the cranium defect procedure without NHC composite repair. At 1, 4, 12, 24, and 40 weeks after surgery, the animals were sacrificed and samples were taken and assessed by gross observation, three-dimensional (3D) computerized tomographic (CT) reconstruction, histology and scanning electron microscope. Our results showed that at 1 week after repairing the bone defect with the NHC composite in the experimental group, new bone appeared around the composite and matured gradually. At 24 weeks after surgery, there were little collagenous tissues present between the material and surrounding bones. At 40 weeks after surgery, new bone had grown into the mature bone and total osseointegration had occurred. In the control group, however, no bone defect healing was observed at 40 weeks after surgery. All these results of the present in vivo work suggest that the NHC composite has a good hard tissue biocompatibility and an excellent osteoconductivity. It is suitable for artificial bone implants and frame materials of tissue engineering.

  20. Hard tissue compatibility of natural hydroxyapatite/chitosan composite

    Energy Technology Data Exchange (ETDEWEB)

    Tang Xiaojun; Gui Lai [Department of Cranio-maxillofacial Surgery, Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 33 Ba-Da-Chu Road, Beijing, 100144 (China); Lue Xiaoying [State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096 (China)], E-mail: laiguiplastic@tom.com, E-mail: luxy@seu.edu.cn

    2008-12-15

    The natural hydroxyapatite/chitosan (NHC) composite is a new synthesized material. The aim of this experiment was to assess the bone tissue compatibility of this NHC composite in vivo. Twenty-four healthy New Zealand rabbits were included in this study. Of those, 20 were used as the experimental group and four as the control group. In the experimental group, animals receive a cranium defect procedure and NHC composite repair. In the control group, animals underwent the cranium defect procedure without NHC composite repair. At 1, 4, 12, 24, and 40 weeks after surgery, the animals were sacrificed and samples were taken and assessed by gross observation, three-dimensional (3D) computerized tomographic (CT) reconstruction, histology and scanning electron microscope. Our results showed that at 1 week after repairing the bone defect with the NHC composite in the experimental group, new bone appeared around the composite and matured gradually. At 24 weeks after surgery, there were little collagenous tissues present between the material and surrounding bones. At 40 weeks after surgery, new bone had grown into the mature bone and total osseointegration had occurred. In the control group, however, no bone defect healing was observed at 40 weeks after surgery. All these results of the present in vivo work suggest that the NHC composite has a good hard tissue biocompatibility and an excellent osteoconductivity. It is suitable for artificial bone implants and frame materials of tissue engineering.

  1. On the connective tissue regulator Follistatin-like 1

    NARCIS (Netherlands)

    Sylva, M.

    2014-01-01

    Even though for many years the molecular mechanisms underlying cardiac development have been studied, the majority of cardiac defects remain unexplained. Defects in the cardiac connective tissue component result in a large proportion of heart defects such as valve and septal defects. Previous

  2. 16 CFR 1115.4 - Defect.

    Science.gov (United States)

    2010-01-01

    ... defect exists. At a minimum, defect includes the dictionary or commonly accepted meaning of the word... appliance presents a shock hazard because, through a manufacturing error, its casing can be electrically... for home garages is advertised as activating when carbon monoxide fumes reach a dangerous level but...

  3. Distribution of defects in wind turbine blades and reliability assessment of blades containing defects

    DEFF Research Database (Denmark)

    Stensgaard Toft, Henrik; Branner, Kim; Berring, Peter

    2009-01-01

    on the assumption that one error in the production process tends to trigger several defects. For both models additional information about number, type and size of the defects is included as stochastic variables. The probability of failure for a wind turbine blade will not only depend on variations in the material......In the present paper two stochastic models for the distribution of defects in wind turbine blades are proposed. The first model assumes that the individual defects are completely randomly distributed in the blade. The second model assumes that the defects occur in clusters of different size based...... properties and the load but also on potential defects in the blades. As a numerical example the probability of failure is calculated for the main spar both with and without defects in terms of delaminations. The delaminations increase the probability of failure compared to a perfect blade, but by applying...

  4. Unicortical critical size defect of rabbit tibia is larger than 8 mm

    DEFF Research Database (Denmark)

    Aaboe, M; Pinholt, E M; Hjørting-Hansen, E

    1994-01-01

    The critical-size defect is important as an experimental model to test bone repair materials. Guided tissue regeneration is an established method for tissue regeneration within periodontal surgery. Bony defects covered by a membrane are allowed to be filled by bony tissue. Healing of 8-mm...

  5. Nanomaterials for Craniofacial and Dental Tissue Engineering.

    Science.gov (United States)

    Li, G; Zhou, T; Lin, S; Shi, S; Lin, Y

    2017-07-01

    Tissue engineering shows great potential as a future treatment for the craniofacial and dental defects caused by trauma, tumor, and other diseases. Due to the biomimetic features and excellent physiochemical properties, nanomaterials are of vital importance in promoting cell growth and stimulating tissue regeneration in tissue engineering. For craniofacial and dental tissue engineering, the frequently used nanomaterials include nanoparticles, nanofibers, nanotubes, and nanosheets. Nanofibers are attractive for cell invasion and proliferation because of their resemblance to extracellular matrix and the presence of large pores, and they have been used as scaffolds in bone, cartilage, and tooth regeneration. Nanotubes and nanoparticles improve the mechanical and chemical properties of scaffold, increase cell attachment and migration, and facilitate tissue regeneration. In addition, nanofibers and nanoparticles are also used as a delivery system to carry the bioactive agent in bone and tooth regeneration, have better control of the release speed of agent upon degradation of the matrix, and promote tissue regeneration. Although applications of nanomaterials in tissue engineering remain in their infancy with numerous challenges to face, the current results indicate that nanomaterials have massive potential in craniofacial and dental tissue engineering.

  6. Uso del regenerador dérmico Integra® como material de relleno para el tratamiento de defectos del contorno corporal Use of Integra® dermal regeneration template in deep tissue planes for contour defects treatment

    Directory of Open Access Journals (Sweden)

    P. A. Gómez Morell

    2007-09-01

    Full Text Available En el tratamiento de los defectos de contorno corporal se usan múltiples productos biológicos y/o sintéticos. Cuando el volumen no es grande, los autores plantean el uso del regenerador dérmico Integra® eliminando previamente su capa superficial de silicona frente a los inconvenientes que presenta el uso de otros materiales de relleno en Cirugía Plástica (reabsorción variable, intolerancia, infección, granulomas, calcificación, etc. Dicho producto acaba transformándose en neodermis del propio paciente, bien tolerada. Presentamos dos casos con defectos a nivel frontal (postraumático y en tórax anterior (secuelas de reconstrucción tras mastectomía respectivamente, en los que se colocó Integra® en bolsillos profundos y doblado sobre sí mismo para aumentar su volumen. Los resultados son previsibles, con mínima reabsorción y además son duraderos, con seguimiento a los 6 y 12 meses. Los autores recomiendan el uso del regenerador dérmico en volúmenes moderados y/o pequeños, considerando que en grandes volúmenes es preferible el uso del colgajos autólogos y/o colgajos más prótesis.In the treatment of body contour defects we can use many biological and synthetic products. They have many inconvenient effects as variable reabsortion, intolerance, infection, granulomas, calcification, etc. In moderate defects, the authors propose the use of modificated Integra® dermal regeneration template without the superficial silicone layer. Two patients are reported, one with a traumatic frontal defect and another with a depression in the anterior thorax after postmastectomy breast reconstruction post mastectomy. In both we put Integra® into a subcutaneous pocket and we bent it to increase lamina volume. Results are predictable, permanent, with minimal reabsortion after 6 and 12 months follow up. Integra® will be autologous neodermis. The authors recommend the dermal regeneration template for small or medium defects; in large defects they

  7. Relatively high rates of G:C → A:T transitions at CpG sites were observed in certain epithelial tissues including pancreas and submaxillary gland of adult big blue® mice.

    Science.gov (United States)

    Prtenjaca, Anita; Tarnowski, Heather E; Marr, Alison M; Heney, Melanie A; Creamer, Laura; Sathiamoorthy, Sarmitha; Hill, Kathleen A

    2014-01-01

    With few exceptions, spontaneous mutation frequency and pattern are similar across tissue types and relatively constant in young to middle adulthood in wild type mice. Underrepresented in surveys of spontaneous mutations across murine tissues is the diversity of epithelial tissues. For the first time, spontaneous mutations were detected in pancreas and submaxillary gland and compared with kidney, lung, and male germ cells from five adult male Big Blue® mice. Mutation load was assessed quantitatively through measurement of mutant and mutation frequency and qualitatively through identification of mutations and characterization of recurrent mutations, multiple mutations, mutation pattern, and mutation spectrum. A total of 9.6 million plaque forming units were screened, 226 mutants were collected, and 196 independent mutations were identified. Four novel mutations were discovered. Spontaneous mutation frequency was low in pancreas and high in the submaxillary gland. The submaxillary gland had multiple recurrent mutations in each of the mice and one mutant had two independent mutations. Mutation patterns for epithelial tissues differed from that observed in male germ cells with a striking bias for G:C to A:T transitions at CpG sites. A comprehensive review of lacI spontaneous mutation patterns in young adult mice and rats identified additional examples of this mutational bias. An overarching observation about spontaneous mutation frequency in adult tissues of the mouse remains one of stability. A repeated observation in certain epithelial tissues is a higher rate of G:C to A:T transitions at CpG sites and the underlying mechanisms for this bias are not known. Copyright © 2013 Wiley Periodicals, Inc.

  8. Effect of systemic administration of nicotine on healing in osseous defects. An experimental study in rabbits. Part II

    DEFF Research Database (Denmark)

    Balatsouka, Dimitra; Gotfredsen, Klaus; Sørensen, Lars

    2006-01-01

    OBJECTIVES: The aim of the present study was to analyze the effect of systemic administration of nicotine on bone healing in osseous defects in the tibia of rabbits. MATERIAL AND METHODS: Sixteen female rabbits received nicotine (n=8; test group) or saline (n=8; control group) via subcutaneously...... 4 weeks and in the left leg after 6 weeks of nicotine/placebo exposure. Thus, 2- and 4-week healing groups were created for the bone defects. After 8 weeks, the animals were killed. Tissue blocks including the bone defects were prepared for histological analysis. RESULTS: The animals in the test...... group lost weight, while the control group gained weight during the experiment. The prostaglandin E(2) levels in plasma increased significantly following nicotine exposure in the test group. No significant differences in the percentage of vessels and bone density in the osseous defects were found...

  9. REPAIR OF LARGE SKULL BASE DEFECT FOLLOWING EXCISION OF BASALOID SQUAMOUS CELL CARCINOMA OF MAXILLO - ETHMOID REGION : A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Monoj Mukherjee

    2015-02-01

    Full Text Available AIM: To present a case of basaloid squamous cell carcinoma of maxillo - ethmoid region with intracranial extradural extention and its surgical management including repair of the skull base defect. MATERIAL : A 30 year female presented with progressive bilateral nasal obstruction, facial deformity for 5 years duration. She developed blindness in last 6 months. Recent CT s can showed large heterogeneous enhancing soft tissue mass in right maxillary sinus, nasal cavity and right ethmoid sinus invading the skull base . INTERVENTION : She underwent excision of the mass by modified weber ferguson incision and repair of skull base defect with temporalis muscle flap. Skin defect over the face and nose was repaired by median forehead flap. RESULT : There was total tumor clearance and no CSF leakage following surgery. CONCLUSION : Sinonasal malignancy with intracranial extradural extenti on is not a contraindication for successful surgical management. Resultant skull base defect can be repaired by a temporalis muscle flap to prevent CSF leak and intracranial infection

  10. External fixation of femoral defects in athymic rats: Applications for human stem cell implantation and bone regeneration

    Directory of Open Access Journals (Sweden)

    Terasa Foo

    2013-01-01

    Full Text Available An appropriate animal model is critical for the research of stem/progenitor cell therapy and tissue engineering for bone regeneration in vivo. This study reports the design of an external fixator and its application to critical-sized femoral defects in athymic rats. The external fixator consists of clamps and screws that are readily available from hardware stores as well as Kirschner wires. A total of 35 rats underwent application of the external fixator with creation of a 6-mm bone defect in one femur of each animal. This model had been used in several separate studies, including implantation of collagen gel, umbilical cord blood mesenchymal stem cells, endothelial progenitor cells, or bone morphogenetic protein-2. One rat developed fracture at the proximal pin site and two rats developed deep tissue infection. Pin loosening was found in nine rats, but it only led to the failure of external fixation in two animals. In 8 to 10 weeks, various degrees of bone growth in the femoral defects were observed in different study groups, from full repair of the bone defect with bone morphogenetic protein-2 implantation to fibrous nonunion with collagen gel implantation. The external fixator used in these studies provided sufficient mechanical stability to the bone defects and had a comparable complication rate in athymic rats as in immunocompetent rats. The external fixator does not interfere with the natural environment of a bone defect. This model is particularly valuable for investigation of osteogenesis of human stem/progenitor cells in vivo.

  11. Combining decellularized human adipose tissue extracellular matrix and adipose-derived stem cells for adipose tissue engineering.

    Science.gov (United States)

    Wang, Lina; Johnson, Joshua A; Zhang, Qixu; Beahm, Elisabeth K

    2013-11-01

    Repair of soft tissue defects resulting from lumpectomy or mastectomy has become an important rehabilitation process for breast cancer patients. This study aimed to provide an adipose tissue engineering platform for soft tissue defect repair by combining decellularized human adipose tissue extracellular matrix (hDAM) and human adipose-derived stem cells (hASCs). To derive hDAM incised human adipose tissues underwent a decellularization process. Effective cell removal and lipid removal were proved by immunohistochemical analysis and DNA quantification. Scanning electron microscopic examination showed a three-dimensional nanofibrous architecture in hDAM. The hDAM included collagen, sulfated glycosaminoglycan, and vascular endothelial growth factor, but lacked major histocompatibility complex antigen I. hASC viability and proliferation on hDAM were proven in vitro. hDAM implanted subcutaneously in Fischer rats did not cause an immunogenic response, and it underwent remodeling, as indicated by host cell infiltration, neovascularization, and adipose tissue formation. Fresh fat grafts (Coleman technique) and engineered fat grafts (hDAM combined with hASCs) were implanted subcutaneously in nude rats. The implanted engineered fat grafts maintained their volume for 8 weeks, and the hASCs contributed to adipose tissue formation. In summary, the combination of hDAM and hASCs provides not only a clinically translatable platform for adipose tissue engineering, but also a vehicle for elucidating fat grafting mechanisms. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Craniotomy Frontal Bone Defect

    African Journals Online (AJOL)

    2018-03-01

    Mar 1, 2018 ... with cosmetic deformity of fore head (Figure 1), and he claimed that he could not get job because of ... 1: Pre-operative forontal view of patient. Figure 2: Intra operative photography of defect (A) reconstructed defect (B) ... with a cosmetic deformity of forehead on left side. (4nA and B). He was a candidate for.

  13. Basement Membrane Defects in Genetic Kidney Diseases

    Directory of Open Access Journals (Sweden)

    Christine Chew

    2018-01-01

    Full Text Available The glomerular basement membrane (GBM is a specialized structure with a significant role in maintaining the glomerular filtration barrier. This GBM is formed from the fusion of two basement membranes during development and its function in the filtration barrier is achieved by key extracellular matrix components including type IV collagen, laminins, nidogens, and heparan sulfate proteoglycans. The characteristics of specific matrix isoforms such as laminin-521 (α5β2γ1 and the α3α4α5 chain of type IV collagen are essential for the formation of a mature GBM and the restricted tissue distribution of these isoforms makes the GBM a unique structure. Detailed investigation of the GBM has been driven by the identification of inherited abnormalities in matrix proteins and the need to understand pathogenic mechanisms causing severe glomerular disease. A well-described hereditary GBM disease is Alport syndrome, associated with a progressive glomerular disease, hearing loss, and lens defects due to mutations in the genes COL4A3, COL4A4, or COL4A5. Other proteins associated with inherited diseases of the GBM include laminin β2 in Pierson syndrome and LMX1B in nail patella syndrome. The knowledge of these genetic mutations associated with GBM defects has enhanced our understanding of cell–matrix signaling pathways affected in glomerular disease. This review will address current knowledge of GBM-associated abnormalities and related signaling pathways, as well as discussing the advances toward disease-targeted therapies for patients with glomerular disease.

  14. Defects at oxide surfaces

    CERN Document Server

    Thornton, Geoff

    2015-01-01

    This book presents the basics and characterization of defects at oxide surfaces. It provides a state-of-the-art review of the field, containing information to the various types of surface defects, describes analytical methods to study defects, their chemical activity and the catalytic reactivity of oxides. Numerical simulations of defective structures complete the picture developed. Defects on planar surfaces form the focus of much of the book, although the investigation of powder samples also form an important part. The experimental study of planar surfaces opens the possibility of applying the large armoury of techniques that have been developed over the last half-century to study surfaces in ultra-high vacuum. This enables the acquisition of atomic level data under well-controlled conditions, providing a stringent test of theoretical methods. The latter can then be more reliably applied to systems such as nanoparticles for which accurate methods of characterization of structure and electronic properties ha...

  15. International conference on defects in insulating crystals

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    Short summaries of conference papers are presented. Some of the conference topics included transport properties, defect levels, superionic conductors, radiation effects, John-Teller effect, electron-lattice interactions, and relaxed excited states. (SDF)

  16. International conference on defects in insulating crystals

    International Nuclear Information System (INIS)

    1977-01-01

    Short summaries of conference papers are presented. Some of the conference topics included transport properties, defect levels, superionic conductors, radiation effects, John-Teller effect, electron-lattice interactions, and relaxed excited states

  17. Role of tissue engineered collagen based tridimensional implant on the healing response of the experimentally induced large Achilles tendon defect model in rabbits: a long term study with high clinical relevance.

    Science.gov (United States)

    Meimandi-Parizi, Abdolhamid; Oryan, Ahmad; Moshiri, Ali

    2013-05-14

    Tendon injury is one of the orthopedic conditions poses with a significant clinical challenge to both the surgeons and patients. The major limitations to manage these injuries are poor healing response and development of peritendinous adhesions in the injured area. This study investigated the effectiveness of a novel collagen implant on tendon healing in rabbits. Seventy five mature White New-Zealand rabbits were divided into treated (n = 55) and control (n = 20) groups. The left Achilles tendon was completely transected and 2 cm excised. The defects of the treated animals were filled with collagen implants and repaired with sutures, but in control rabbits the defects were sutured similarly but the gap was left untreated. Changes in the injured and normal contralateral tendons were assessed weekly by measuring the diameter, temperature and bioelectrical characteristics of the injured area. Clinical examination was done and scored. Among the treated animals, small pilot groups were euthanized at 5, 10, 15, 20, 30, 40 and 60 (n = 5 at each time interval) and the remainder (n = 20) and the control animals at 120 days post injury (DPI). The lesions of all animals were examined at macroscopic and microscopic levels and the dry matter content, water delivery and water uptake characteristics of the lesions and normal contralateral tendons of both groups were analyzed at 120 DPI. This novel collagen implant was biodegradable, biocompatible and possibly could be considered as a substitute for auto and allografts in clinical practice in near future.

  18. Intercalary bone segment transport in treatment of segmental tibial defects

    International Nuclear Information System (INIS)

    Iqbal, A.; Amin, M.S.

    2002-01-01

    Objective: To evaluate the results and complications of intercalary bone segment transport in the treatment of segmental tibial defects. Design: This is a retrospective analysis of patients with segmental tibial defects who were treated with intercalary bone segment transport method. Place and Duration of Study: The study was carried out at Combined Military Hospital, Rawalpindi from September 1997 to April 2001. Subjects and methods: Thirteen patients were included in the study who had developed tibial defects either due to open fractures with bone loss or subsequent to bone debridement of infected non unions. The mean bone defect was 6.4 cms and there were eight associated soft tissue defects. Locally made unilateral 'Naseer-Awais' (NA) fixator was used for bone segment transport. The distraction was done at the rate of 1mm/day after 7-10 days of osteotomy. The patients were followed-up fortnightly during distraction and monthly thereafter. The mean follow-up duration was 18 months. Results: The mean time in external fixation was 9.4 months. The m ean healing index' was 1.47 months/cm. Satisfactory union was achieved in all cases. Six cases (46.2%) required bone grafting at target site and in one of them grafting was required at the level of regeneration as well. All the wounds healed well with no residual infection. There was no residual leg length discrepancy of more than 20 mm nd one angular deformity of more than 5 degrees. The commonest complication encountered was pin track infection seen in 38% of Shanz Screws applied. Loosening occurred in 6.8% of Shanz screws, requiring re-adjustment. Ankle joint contracture with equinus deformity and peroneal nerve paresis occurred in one case each. The functional results were graded as 'good' in seven, 'fair' in four, and 'poor' in two patients. Overall, thirteen patients had 31 (minor/major) complications with a ratio of 2.38 complications per patient. To treat the bone defects and associated complications, a mean of

  19. Classification and Methods of Shrinkage Defect Control

    Directory of Open Access Journals (Sweden)

    N. S. Larichev

    2016-01-01

    Full Text Available The objective is to put forward a proposal to divide the internal shrinkage defects into the dimensional levels according to defects of certain size and shape.The paper presents the terminology used to describe the internal shrinkage defects in the casting and shows its flaws. These include the lack of well-defined threshold size values and shape of defects. It is shown that in describing defects their sizes and shape are defined qualitatively rather than quantitatively. And it is noted that division of defects into pores and shells is based on the morphological characters.The paper notes that a distinct difference between defects is necessary because of different methods of their elimination from the casting body.The paper presents an overview of control methods to determine the defects of the shrinkage nature in castings. These are methods of destructive and non-destructive testing, such as Xrays, tomography, and metallography. The paper also shows advantages and disadvantages of the considered methods of control. Based on the control method capacities it offers to divide the shrinkage defects into the three dimensional levels.To estimate the shape of defects the paper suggests a new option, that is a shape criterion. By the example of the typical defects of each dimensional level are defined the threshold values of the shape criterion.The paper discusses the basic techniques to estimate the porosity and offers a relationship between the defects of different dimensional levels and a porosity score and percent. It shows that the transition from a dimensional level to another one is in line with not only increasing pore size, but also with a significant deterioration of the mechanical properties of castings.The main conclusions are as follows:1. At present, there is no single unambiguous classification of casting shrinkage defects in the technical literature.2. As follows from the analysis of the classifications of shrinkage defects, their

  20. Buildability as a tool for optimisation of building defects

    DEFF Research Database (Denmark)

    Nielsen, Jørgen; Hansen, Ernst Jan de Place; Aagaard, Niels-Jørgen

    2009-01-01

    Defects in buildings harm the reputation of the construction industry and the amount of defects is believed to represent a loss in economy. The purpose is to study whether the buildability concept could serve as an efficient tool for reduction of defects. The project includes a literature study...

  1. A detailed model for defect concentration and dopant activation in ...

    Indian Academy of Sciences (India)

    Unknown

    We have also included Si and related defects when this element is implanted as an n-type dopant. All these defects are considered in several charge states allowed by their stability conditions. The model assumes thermodynamic equilibrium between the point defects at an anneal temperature. Then the GaAs wafer.

  2. Defect relaxation in disordered materials

    International Nuclear Information System (INIS)

    Crandell, R.S.

    1989-01-01

    Using an exponential distribution of activation barriers, annealing data for metastable effects in hydrogenated amorphous silicon, a-Si:H, are quantitatively explained. This includes the stretched exponential time dependence of annealing and a Meyer-Neldel rule for the annealing time constant. An exponential distribution of annealing energies arises because defects are frozen in during growth at high temperature. Mechanisms that lead to an exponential distribution of annealing energies are weak bond-breaking and charge trapping

  3. Neonatal septum transversum diaphragmatic defects

    International Nuclear Information System (INIS)

    Wesselhoeft, C.W. Jr.; DeLuca, F.G.

    1984-01-01

    Over 10 years, 8 infants required surgery for central diaphragmatic herniation. Contrast peritoneography and technetium-99m-sulfur colloid radionuclide scanning were the most definitive diagnostic aids. Associated anomalies included variations of the pentalogy of Cantrell. A midline gastroduodenal loop was found in two infants. Six infants are alive and well 6 months to 3 years postoperatively. An abdominal approach is preferred if there is an intestinal hernia, associated gastrointestinal anomalies, or if a bilateral defect is present

  4. Neonatal septum transversum diaphragmatic defects

    Energy Technology Data Exchange (ETDEWEB)

    Wesselhoeft, C.W. Jr.; DeLuca, F.G.

    1984-04-01

    Over 10 years, 8 infants required surgery for central diaphragmatic herniation. Contrast peritoneography and technetium-99m-sulfur colloid radionuclide scanning were the most definitive diagnostic aids. Associated anomalies included variations of the pentalogy of Cantrell. A midline gastroduodenal loop was found in two infants. Six infants are alive and well 6 months to 3 years postoperatively. An abdominal approach is preferred if there is an intestinal hernia, associated gastrointestinal anomalies, or if a bilateral defect is present.

  5. Screening Tests for Birth Defects

    Science.gov (United States)

    ... Advocacy For Patients About ACOG Screening Tests for Birth Defects Home For Patients Search FAQs Screening Tests ... FAQ165, April 2014 PDF Format Screening Tests for Birth Defects Pregnancy What is a birth defect? What ...

  6. Evaluation of Bone Regeneration on Polyhydroxyethyl-polymethyl Methacrylate Membrane in a Rabbit Calvarial Defect Model.

    Science.gov (United States)

    Kim, Somin; Hwang, Yawon; Kashif, Muhammad; Jeong, Dosun; Kim, Gonhyung

    This study was conducted to evaluate the capacity of guiding bone regeneration of polyhydroxyethyl-polymethyl methacrylate (PHEMA-PMMA) membrane as a guided tissue regeneration membrane for bone defects. Two 8-mm diameter transosseous round defects were made at the parietal bone of 18 New Zealand White rabbits. Defects were covered with or without PHEMA-PMMA membrane. Radiological and histological evaluation revealed that the bone tissue over the defect was more regenerated with time in both groups. However, there was significantly more bone regeneration at 8 weeks in the experimental group than the control group (p<0.05). There was no sign of membrane degradation or tissue inflammation and no invasion of muscle and fibrous tissue into defects. PHEMA-PMMA is a potential material for guided tissue regeneration membrane as it induces no adverse tissue reaction and effectively supports selective bone regeneration. Copyright © 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  7. Defect distribution and reliability assessment of wind turbine blades

    DEFF Research Database (Denmark)

    Stensgaard Toft, Henrik; Branner, Kim; Berring, Peter

    2011-01-01

    on the assumption that one error in the production process tends to trigger several defects. For both models, additional information, such as number, type, and size of the defects, is included as stochastic variables. In a numerical example, the reliability is estimated for a generic wind turbine blade model both...... with and without defects in terms of delaminations. The reliability of the blade decreases when defects are included. However, the distribution of the defects influences how much the reliability is decreased. It is also shown how non-destructive inspection (NDI) after production can be used to update...... the reliability for the wind turbine blade using Bayesian statistics....

  8. Nanocarbon: Defect Architectures and Properties

    Science.gov (United States)

    Vuong, Amanda

    The allotropes of carbon make its solid phases amongst the most diverse of any element. It can occur naturally as graphite and diamond, which have very different properties that make them suitable for a wide range of technological and commercial purposes. Recent developments in synthetic carbon include Highly Oriented Pyrolytic Graphite (HOPG) and nano-carbons, such as fullerenes, nanotubes and graphene. The main industrial application of bulk graphite is as an electrode material in steel production, but in purified nuclear graphite form, it is also used as a moderator in Advanced Gas-cooled Reactors across the United Kingdom. Both graphene and graphite are damaged over time when subjected to bombardment by electrons, neutrons or ions, and these have a wide range of effects on their physical and electrical properties, depending on the radiation flux and temperature. This research focuses on intrinsic defects in graphene and dimensional change in nuclear graphite. The method used here is computational chemistry, which complements physical experiments. Techniques used comprise of density functional theory (DFT) and molecular dynamics (MD), which are discussed in chapter 2 and chapter 3, respectively. The succeeding chapters describe the results of simulations performed to model defects in graphene and graphite. Chapter 4 presents the results of ab initio DFT calculations performed to investigate vacancy complexes that are formed in AA stacked bilayer graphene. In AB stacking, carbon atoms surrounding the lattice vacancies can form interlayer structures with sp2 bonding that are lower in energy compared to in-plane reconstructions. From the investigation of AA stacking, sp2 interlayer bonding of adjacent multivacancy defects in registry creates a type of stable sp2 bonded wormhole between the layers. Also, a new class of mezzanine structure characterised by sp3 interlayer bonding, resembling a prismatic vacancy loop has also been identified. The mezzanine, which is a

  9. Tissue Classification

    DEFF Research Database (Denmark)

    Van Leemput, Koen; Puonti, Oula

    2015-01-01

    Computational methods for automatically segmenting magnetic resonance images of the brain have seen tremendous advances in recent years. So-called tissue classification techniques, aimed at extracting the three main brain tissue classes (white matter, gray matter, and cerebrospinal fluid), are now...... well established. In their simplest form, these methods classify voxels independently based on their intensity alone, although much more sophisticated models are typically used in practice. This article aims to give an overview of often-used computational techniques for brain tissue classification....... Although other methods exist, we concentrate on Bayesian modeling approaches, in which generative image models are constructed and subsequently ‘inverted’ to obtain automated segmentations. This general framework encompasses a large number of segmentation methods, including those implemented in widely used...

  10. Traffic jam in the primitive streak: the role of defective mesoderm migration in birth defects.

    Science.gov (United States)

    Herion, Nils J; Salbaum, J Michael; Kappen, Claudia

    2014-08-01

    Gastrulation is the process in which the three germ layers are formed that contribute to the formation of all major tissues in the developing embryo. We here review mouse genetic models in which defective gastrulation leads to mesoderm insufficiencies in the embryo. Depending on severity of the abnormalities, the outcomes range from incompatible with embryonic survival to structural birth defects, such as heart defects, spina bifida, or caudal dysgenesis. The combined evidence from the mutant models supports the notion that these congenital anomalies can originate from perturbations of mesoderm specification, epithelial-mesenchymal transition, and mesodermal cell migration. Knowledge about the molecular pathways involved may help to improve strategies for the prevention of major structural birth defects. © 2014 Wiley Periodicals, Inc.

  11. Functional reconstruction of complex tendo Achilles defect by free latissimus dorsi muscle flap

    Directory of Open Access Journals (Sweden)

    Divya N Upadhyaya

    2012-01-01

    Full Text Available Managing the complex tendo Achilles defect involves reconstructing the Achilles tendon as well as providing soft tissue cover to the heel area. The advent of microsurgery has revolutionised the reconstruction of this difficult defect providing a number of options to the reconstructive surgeon. We present a case of complex tendo Achilles defect reconstructed by the latissimus dorsi free flap.

  12. Single Ventricle Defects

    Science.gov (United States)

    ... heart defects along with pulmonary atresia. (Children with tetralogy of Fallot who also have pulmonary atresia may have treatment similar to others with tetralogy of Fallot.) How does it affect the heart? An opening ...

  13. Repairing Nanoparticle Surface Defects

    NARCIS (Netherlands)

    Marino, Emanuele; Kodger, Thomas E.; Crisp, R.W.; Timmerman, Dolf; MacArthur, Katherine E.; Heggen, Marc; Schall, Peter

    2017-01-01

    Solar devices based on semiconductor nanoparticles require the use of conductive ligands; however, replacing the native, insulating ligands with conductive metal chalcogenide complexes introduces structural defects within the crystalline nanostructure that act as traps for charge carriers. We

  14. Neural tube defects

    Directory of Open Access Journals (Sweden)

    M.E. Marshall

    1981-09-01

    Full Text Available Neural tube defects refer to any defect in the morphogenesis of the neural tube, the most common types being spina bifida and anencephaly. Spina bifida has been recognised in skeletons found in north-eastern Morocco and estimated to have an age of almost 12 000 years. It was also known to the ancient Greek and Arabian physicians who thought that the bony defect was due to the tumour. The term spina bifida was first used by Professor Nicolai Tulp of Amsterdam in 1652. Many other terms have been used to describe this defect, but spina bifida remains the most useful general term, as it describes the separation of the vertebral elements in the midline.

  15. Wilms tumor arising in extracoelomic paravertebral soft tissues.

    LENUS (Irish Health Repository)

    Mulligan, Linda

    2012-02-01

    Extrarenal Wilms tumor (ERWT) is a well-established entity which most commonly arises within the genitourinary tract, including intracoelomic paranephric soft tissue. Rarely, ERWT arises within teratoma, and it tends to occur predominantly in distinct settings, such as females with spinal defects and males with testicular teratomas. We report a unique ERWT arising within an extracoelomic teratoma of the paraspinal musculature, thereby expanding the range of reported locations for this unusual tumor.

  16. ILT based defect simulation of inspection images accurately predicts mask defect printability on wafer

    Science.gov (United States)

    Deep, Prakash; Paninjath, Sankaranarayanan; Pereira, Mark; Buck, Peter

    2016-05-01

    At advanced technology nodes mask complexity has been increased because of large-scale use of resolution enhancement technologies (RET) which includes Optical Proximity Correction (OPC), Inverse Lithography Technology (ILT) and Source Mask Optimization (SMO). The number of defects detected during inspection of such mask increased drastically and differentiation of critical and non-critical defects are more challenging, complex and time consuming. Because of significant defectivity of EUVL masks and non-availability of actinic inspection, it is important and also challenging to predict the criticality of defects for printability on wafer. This is one of the significant barriers for the adoption of EUVL for semiconductor manufacturing. Techniques to decide criticality of defects from images captured using non actinic inspection images is desired till actinic inspection is not available. High resolution inspection of photomask images detects many defects which are used for process and mask qualification. Repairing all defects is not practical and probably not required, however it's imperative to know which defects are severe enough to impact wafer before repair. Additionally, wafer printability check is always desired after repairing a defect. AIMSTM review is the industry standard for this, however doing AIMSTM review for all defects is expensive and very time consuming. Fast, accurate and an economical mechanism is desired which can predict defect printability on wafer accurately and quickly from images captured using high resolution inspection machine. Predicting defect printability from such images is challenging due to the fact that the high resolution images do not correlate with actual mask contours. The challenge is increased due to use of different optical condition during inspection other than actual scanner condition, and defects found in such images do not have correlation with actual impact on wafer. Our automated defect simulation tool predicts

  17. Evaluation of Polyurethane Membrane as a Barrier in Treatment of Intrabony Defects

    Directory of Open Access Journals (Sweden)

    Haghighati F

    2000-05-01

    Full Text Available Clinical healing following guided tissue regeneration (GTR in intrabony pockets using a"npolyurethane membrane was compared to healing following gingival flap surgery (GFS."nTen patients with adult periodontitis and the presence of intrabony defects were selected. Oral hygenic"ntreatments were performed during a 4- weeks period prior to surgery."nOne intrabony defects on each patient was randomly chosen to be treated according to the guided tissue"nregeneration (GTR procedure. The other side received the control treatment GFS. Test group received"nthe GTP treatment including polyurethane membrane after reflecting the flap and curettage of defect."nHowever, flap surgery and curettage were done in control group."nThe patients were evaluated for changes in probing depth (PD, clinical attachment level (CAL,"nrecession changes in crestai resorting, and defect bone fill. Clinical examinations were performed again 6"nmonths post operatively."nThe average of (PD, (CAL and defect depth (DD before surgery in test group was 3.23, 13.87 and 7.3"nmm respectively and in control group was 3.1, 8.9, 7.4 mm. After 6 months the average of (PD, (CAL"nand (DD was 1.69, 1.68, 3.5 mm, respectively and in control group was 1.24, 1.09, and 2.90mm."nTest group and control group showed successful results in treatment of intrabony defects. Test group"nshowed better results than control."nNo significant difference was observed between two treatment procedures from the point of view of"npocket depth reduction, attachment gain, and recession."nThe bony fill and crestai resorption results suggest similar clinical potential of GTR procedures"ncompared to GFS in treatment of intrabony pocket. However, in order to gain future insight, larger"nsamples and longer observation periods should be evaluated.

  18. The effects of defects on copper melting under hydrostatic and shock loading

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Shengnian [Los Alamos National Laboratory; An, Qi [Los Alamos National Laboratory; Germann, Timothy C [Los Alamos National Laboratory; Han, Li - Bo [USTC

    2009-07-24

    With molecular dynamics (MD) simulations, we investigate the effects of defects on Cu melting under hydrostatic and shock wave loading. We explore preexistent defects including vacancies, stacking faults and grain boundaries, as well as shock-induced defects. Depending on defect characteristics (energy and concentration), defects may have negligible or considerable effects on melting at MD scales However, it is expected that defects have more pronounced effects at heating rates lower than the MD rates.

  19. Microsurgical Composite Tissue Transplantation

    Science.gov (United States)

    Serafin, Donald; Georgiade, Nicholas G.

    1978-01-01

    Since 1974, 69 patients with extensive defects have undergone reconstruction by microsurgical composite tissue transplantation. Using this method, donor composite tissue is isolated on its blood supply, removed to a distant recipient site, and the continuity of blood flow re-established by microvascular anastomoses. In this series, 56 patients (81%) were completely successful. There have been eight (12%) failures, primarily in the extremities. There have been five (7%) partial successes, (i.e., a microvascular flap in which a portion was lost requiring a secondary procedure such as a split thickness graft). In those patients with a severely injured lower extremity, the failure rate was the greatest. Most of these were arterial (six of seven). These failures occurred early in the series and were thought to be related to a severely damaged recipient vasculature. This problem has been circumvented by an autogenous interpositional vein graft, permitting more mobility of flap placement. In the upper extremity, all but one case were successful. Early motion was permitted, preventing joint capsular contractures and loss of function. Twenty-three cases in the head and neck region were successful (one partial success). This included two composite rib grafts to the mandible. Prolonged delays in reconstruction following extirpation of a malignancy were avoided. A rapid return to society following complete reconstruction was ensured. Nine patients presented for reconstruction of the breast and thorax following radical mastectomy. All were successfully reconstructed with this new technique except one patient. Its many advantages include immediate reconstruction without delayed procedures and no secondary deformity of the donor site. Healthy, well vascularized tissue can now be transferred to a previously irradiated area with no tissue loss. This new method offers many advantages to older methods of reconstruction. Length of hospital stay and immobilization are reduced. The

  20. Evaluation of detectable defect size for inner defect of pressure vessel using laser speckle

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyeoung Suk; Seon, Sang Woo; Choi, Tae Ho; Kang, Chan Geun; Na, Man Gyun; Jung, Hyun Chul [Chsoun University, Gwangju (Korea, Republic of)

    2014-04-15

    Pressure vessels are used in various industrial fields. If a defect occurs on the inner or outer surface of a pressure vessel, it may cause a massive accident. A defect on the outer surface can be detected by visual inspection. However, a defect on the inner surface is generally impossible to detect with visual inspection. Nondestructive testing can be used to detect this type of defect. Laser speckle shearing interferometry is one nondestructive testing method that can optically detect a defect; its advantages include noncontact, full field, and real time inspection. This study evaluated the detectable size for an internal defect of a pressure vessel. The material of the pressure vessel was ASTM A53 Gr.B. The internal defect was detected when the pressure vessel was loaded by internal pressure controlled by a pneumatic system. The internal pressure was controlled from 0.2 MPa to 0.6 MPa in increments of 0.2 MPa. The results confirmed that an internal defect with a 25 % defect depth could be detected even at 0.2 MPa pressure variation.

  1. Multiscale simulations of defect dipole-enhanced electromechanical coupling at dilute defect concentrations

    Science.gov (United States)

    Liu, Shi; Cohen, R. E.

    2017-08-01

    The role of defects in solids of mixed ionic-covalent bonds such as ferroelectric oxides is complex. Current understanding of defects on ferroelectric properties at the single-defect level remains mostly at the empirical level, and the detailed atomistic mechanisms for many defect-mediated polarization-switching processes have not been convincingly revealed quantum mechanically. We simulate the polarization-electric field (P-E) and strain-electric field (ɛ-E) hysteresis loops for BaTiO3 in the presence of generic defect dipoles with large-scale molecular dynamics and provide a detailed atomistic picture of the defect dipole-enhanced electromechanical coupling. We develop a general first-principles-based atomistic model, enabling a quantitative understanding of the relationship between macroscopic ferroelectric properties and dipolar impurities of different orientations, concentrations, and dipole moments. We find that the collective orientation of dipolar defects relative to the external field is the key microscopic structure feature that strongly affects materials hardening/softening and electromechanical coupling. We show that a small concentration (≈0.1 at. %) of defect dipoles dramatically improves electromechanical responses. This offers the opportunity to improve the performance of inexpensive polycrystalline ferroelectric ceramics through defect dipole engineering for a range of applications including piezoelectric sensors, actuators, and transducers.

  2. Defects of mitochondrial DNA replication.

    Science.gov (United States)

    Copeland, William C

    2014-09-01

    Mitochondrial DNA is replicated by DNA polymerase γ in concert with accessory proteins such as the mitochondrial DNA helicase, single-stranded DNA binding protein, topoisomerase, and initiating factors. Defects in mitochondrial DNA replication or nucleotide metabolism can cause mitochondrial genetic diseases due to mitochondrial DNA deletions, point mutations, or depletion, which ultimately cause loss of oxidative phosphorylation. These genetic diseases include mitochondrial DNA depletion syndromes such as Alpers or early infantile hepatocerebral syndromes, and mitochondrial DNA deletion disorders, such as progressive external ophthalmoplegia, ataxia-neuropathy, or mitochondrial neurogastrointestinal encephalomyopathy. This review focuses on our current knowledge of genetic defects of mitochondrial DNA replication (POLG, POLG2, C10orf2, and MGME1) that cause instability of mitochondrial DNA and mitochondrial disease. © The Author(s) 2014.

  3. Vancomycin graft composite for infected bone defects

    International Nuclear Information System (INIS)

    Winkler, H.; Janata, O.; Georgopoulos, A.

    1999-01-01

    Reconstructive surgery under septic conditions represents a major challenge in orthopaedics. Local application of antibiotics can provide high drug levels at the site of infection without systemic effects. However, removal of non-resorbable implants and filling of defects usually requires additional operative procedures. An ideal antibiotic carrier should provide for : 1) Effective bactericidal activity, especially against staphylococci including MRSA; 2) High and long lasting levels at the site of infection without local or systemic toxicity; 3) Repair of defects without a second stage procedure. Allogeneic cancellous bone is proven to be effective in restoration of bone stock. Vancomycin is effective against all gram-positive populations and the agent of choice for infections with MRSA. The aim of our study is to investigate the efficacy of a combination of both components in bone infection. Cancellous bone of human origin was processed during several steps and incubated in 10% vancomycin solution. The antimicrobial activity of the vancomycin graft composite (VGC) was evaluated using an agar diffusion bioassay against staphylococcus aureus and high performance liquid chromatography (HPLC). The testing period was up to 9 weeks. Elution of vancomycin from the graft was evaluated in 2.5% human albumin solution, which was exchanged every 24 hours. Concentration of vancomycin in allograft-bone was between 6.653[tg/g and 23.194gg/g with an average of 15.250 [tg/g, which is equivalent to 10.000 times the minimum inhibitory concentration (MIC) for s. aureus. The initial activity decreased to approx. 50% during the first week and approx. 30% at the end of the 9th week. The lowest values measured exceeded the MIC by 2000 times. Concentration in surrounding fluid decreased from 24.395,80 to 18,43pg/ml after 11 complete exchanges. Human cancellous bone, processed in an adequate way, offers capability to store high quantities of vancomycin. Vancomycin graft composites are

  4. Pedicled Descending Branch Latissimus Dorsi Mini-flap for Repairing Partial Mastectomy Defect: A New Technique

    Directory of Open Access Journals (Sweden)

    Ruizhao Cai, M.D.

    2018-03-01

    Full Text Available Summary:. Volume loss is 1 of the major factors influencing cosmetic outcomes of breast after partial mastectomy (PM, especially for smaller breasts, and therefore, volume replacement is critical for optimizing the final aesthetic outcome. We present a novel technique of raising a pedicled descending branch latissimus dorsi (LD mini-flap for reconstruction of PM defects via an axillary incision. After PM, the LD mini-flap is harvested through the existing axillary incision of the axillary dissection or the sentinel lymph node biopsy. The descending branches of thoracodorsal vessels and nerve are carefully identified and isolated. The transverse branches are protected to maintain muscle innervation and function. The LD muscle is then undermined posteriorly and inferiorly to create a submuscular pocket and a subcutaneous pocket between LD muscle and superficial fascia. Once the submuscular plane is created, the muscle is divided along the muscle fibers from the deep surface including a layer of fat above the muscle. Finally, the LD mini-flap is transferred to the breast defect. Given the limited length and mobility of the LD mini-flap, this approach is best utilized for lateral breast defects. However, for medial defects, the lateral breast tissue is rearranged to reconstruct the medial breast defect, and an LD mini-flap is then used to reconstruct the lateral breast donor site. This technique can therefore be employed to reconstruct all quadrants of the breast and can provide aesthetic outcomes without scars on the back, with minimal dysfunction of LD muscle.

  5. Vertebral defect, anal atresia, cardiac defect, tracheoesophageal fistula/esophageal atresia, renal defect, and limb defect association with Mayer-Rokitansky-Küster-Hauser syndrome in co-occurrence: two case reports and a review of the literature.

    Science.gov (United States)

    Bjørsum-Meyer, Thomas; Herlin, Morten; Qvist, Niels; Petersen, Michael B

    2016-12-21

    defect, and limb defect association and Mayer-Rokitansky-Küster-Hauser syndrome is extremely rare. This group of patients has unusual phenotypic characteristics. The long-term outcome after treatment of defects is not well reported. A single unifying cause is not known and the etiology probably includes both genetic and non-genetic causes. We stress the importance of future studies to optimized treatment, follow-up, and etiology.

  6. Stem cells in bone tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Jeong Min [Department of Preventive and Social Dentistry and Institute of Oral Biology, College of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Kim, Byung-Chul; Park, Jae-Hong; Kwon, Il Keun; Hwang, Yu-Shik [Department of Maxillofacial Biomedical Engineering and Institute of Oral Biology, College of Dentistry, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Mantalaris, Anathathios, E-mail: yshwang@khu.ac.k [Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom)

    2010-12-15

    Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have received extensive attention in the field of bone tissue engineering due to their distinct biological capability to differentiate into osteogenic lineages. The application of these stem cells to bone tissue engineering requires inducing in vitro differentiation of these cells into bone forming cells, osteoblasts. For this purpose, efficient in vitro differentiation towards osteogenic lineage requires the development of well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source for application to bone tissue engineering therapies. This review provides a critical examination of the various experimental strategies that could be used to direct the differentiation of ESC, BM-MSC, UCB-MSC, ADSC, MDSC and DPSC towards osteogenic lineages and their potential applications in tissue engineering, particularly in the regeneration of bone. (topical review)

  7. Bone Tissue Engineering: Recent Advances and Challenges

    Science.gov (United States)

    Amini, Ami R.; Laurencin, Cato T.; Nukavarapu, Syam P.

    2013-01-01

    The worldwide incidence of bone disorders and conditions has trended steeply upward and is expected to double by 2020, especially in populations where aging is coupled with increased obesity and poor physical activity. Engineered bone tissue has been viewed as a potential alternative to the conventional use of bone grafts, due to their limitless supply and no disease transmission. However, bone tissue engineering practices have not proceeded to clinical practice due to several limitations or challenges. Bone tissue engineering aims to induce new functional bone regeneration via the synergistic combination of biomaterials, cells, and factor therapy. In this review, we discuss the fundamentals of bone tissue engineering, highlighting the current state of this field. Further, we review the recent advances of biomaterial and cell-based research, as well as approaches used to enhance bone regeneration. Specifically, we discuss widely investigated biomaterial scaffolds, micro- and nano-structural properties of these scaffolds, and the incorporation of biomimetic properties and/or growth factors. In addition, we examine various cellular approaches, including the use of mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), adult stem cells, induced pluripotent stem cells (iPSCs), and platelet-rich plasma (PRP), and their clinical application strengths and limitations. We conclude by overviewing the challenges that face the bone tissue engineering field, such as the lack of sufficient vascularization at the defect site, and the research aimed at functional bone tissue engineering. These challenges will drive future research in the field. PMID:23339648

  8. Stem cells in bone tissue engineering

    International Nuclear Information System (INIS)

    Seong, Jeong Min; Kim, Byung-Chul; Park, Jae-Hong; Kwon, Il Keun; Hwang, Yu-Shik; Mantalaris, Anathathios

    2010-01-01

    Bone tissue engineering has been one of the most promising areas of research, providing a potential clinical application to cure bone defects. Recently, various stem cells including embryonic stem cells (ESCs), bone marrow-derived mesenchymal stem cells (BM-MSCs), umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs), adipose tissue-derived stem cells (ADSCs), muscle-derived stem cells (MDSCs) and dental pulp stem cells (DPSCs) have received extensive attention in the field of bone tissue engineering due to their distinct biological capability to differentiate into osteogenic lineages. The application of these stem cells to bone tissue engineering requires inducing in vitro differentiation of these cells into bone forming cells, osteoblasts. For this purpose, efficient in vitro differentiation towards osteogenic lineage requires the development of well-defined and proficient protocols. This would reduce the likelihood of spontaneous differentiation into divergent lineages and increase the available cell source for application to bone tissue engineering therapies. This review provides a critical examination of the various experimental strategies that could be used to direct the differentiation of ESC, BM-MSC, UCB-MSC, ADSC, MDSC and DPSC towards osteogenic lineages and their potential applications in tissue engineering, particularly in the regeneration of bone. (topical review)

  9. El colgajo muscular de hemitríceps sural para la cobertura de grandes defectos en la pierna: Experiencia de 9 años The sural hemitriceps muscular flap for reconstruction of large tissue defects of the leg: A 9 year experience

    Directory of Open Access Journals (Sweden)

    R. Graciano Balcón

    2009-09-01

    Full Text Available En el Instituto Nacional de Ortopedia y Traumatología de Montevideo, Uruguay, utilizamos el colgajo muscular de hemitríceps sural para reconstruir defectos de cobertura en traumatismos graves de pierna que asientan en el tercio medio y en la unión del tercio medio con el distal. El colgajo de hemitríceps sural permite cubrir exposiciones óseas más extensas que el colgajo de hemisóleo en forma aislada, con un menor tiempo quirúrgico y sin afectar a la potencia en la flexión plantar. Presentamos una serie de 13 casos clínicos de fracturas expuestas con importantes defectos de cobertura cutánea de la pierna, tratados con colgajos de hemitríceps durante el período marzo de 1999 a julio de 2008. El seguimiento promedio fue de 15 meses.The sural hemitriceps muscular flap is used in the National Institute of Orthopedics and Traumatology in Montevideo to reconstruct soft-tissue defects after severe lower extremity trauma on the middle third and the union of the middle and inferior third of the leg. The hemitriceps sural flap can successfully cover more extensive osseous exposure than the hemisoleus flap alone, with less surgical time and without affecting plantar flexion strength. A series of 13 cases is presented of leg open fractures with important cutaneous soft-tissue defect treated with hemitriceps flaps, operated on the period from march 1999 to july 2008. Average follow-up time was 15 months.

  10. A bioactive "self-fitting" shape memory polymer scaffold with potential to treat cranio-maxillo facial bone defects.

    Science.gov (United States)

    Zhang, Dawei; George, Olivia J; Petersen, Keri M; Jimenez-Vergara, Andrea C; Hahn, Mariah S; Grunlan, Melissa A

    2014-11-01

    While tissue engineering is a promising alternative for treating critical-sized cranio-maxillofacial bone defects, improvements in scaffold design are needed. In particular, scaffolds that can precisely match the irregular boundaries of bone defects as well as exhibit an interconnected pore morphology and bioactivity would enhance tissue regeneration. In this study, a shape memory polymer (SMP) scaffold was developed exhibiting an open porous structure and the capacity to conformally "self-fit" into irregular defects. The SMP scaffold was prepared via photocrosslinking of poly(ε-caprolactone) (PCL) diacrylate using a SCPL method, which included a fused salt template. A bioactive polydopamine coating was applied to coat the pore walls. Following exposure to warm saline at T>T(trans) (T(trans)=T(m) of PCL), the scaffold became malleable and could be pressed into an irregular model defect. Cooling caused the scaffold to lock in its temporary shape within the defect. The polydopamine coating did not alter the physical properties of the scaffold. However, polydopamine-coated scaffolds exhibited superior bioactivity (i.e. formation of hydroxyapatite in vitro), osteoblast adhesion, proliferation, osteogenic gene expression and extracellular matrix deposition. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  11. Effects of mechanical loading on cortical defect repair using a novel mechanobiological model of bone healing.

    Science.gov (United States)

    Liu, Chao; Carrera, Robert; Flamini, Vittoria; Kenny, Lena; Cabahug-Zuckerman, Pamela; George, Benson M; Hunter, Daniel; Liu, Bo; Singh, Gurpreet; Leucht, Philipp; Mann, Kenneth A; Helms, Jill A; Castillo, Alesha B

    2018-03-01

    Mechanical loading is an important aspect of post-surgical fracture care. The timing of load application relative to the injury event may differentially regulate repair depending on the stage of healing. Here, we used a novel mechanobiological model of cortical defect repair that offers several advantages including its technical simplicity and spatially confined repair program, making effects of both physical and biological interventions more easily assessed. Using this model, we showed that daily loading (5N peak load, 2Hz, 60 cycles, 4 consecutive days) during hematoma consolidation and inflammation disrupted the injury site and activated cartilage formation on the periosteal surface adjacent to the defect. We also showed that daily loading during the matrix deposition phase enhanced both bone and cartilage formation at the defect site, while loading during the remodeling phase resulted in an enlarged woven bone regenerate. All loading regimens resulted in abundant cellular proliferation throughout the regenerate and fibrous tissue formation directly above the defect demonstrating that all phases of cortical defect healing are sensitive to physical stimulation. Stress was concentrated at the edges of the defect during exogenous loading, and finite element (FE)-modeled longitudinal strain (ε zz ) values along the anterior and posterior borders of the defect (~2200με) was an order of magnitude larger than strain values on the proximal and distal borders (~50-100με). It is concluded that loading during the early stages of repair may impede stabilization of the injury site important for early bone matrix deposition, whereas loading while matrix deposition and remodeling are ongoing may enhance stabilization through the formation of additional cartilage and bone. Published by Elsevier Inc.

  12. Transplantation of an LGR6+ Epithelial Stem Cell-Enriched Scaffold for Repair of Full-Thickness Soft-Tissue Defects: The In Vitro Development of Polarized Hair-Bearing Skin.

    Science.gov (United States)

    Lough, Denver M; Wetter, Nathan; Madsen, Christopher; Reichensperger, Joel; Cosenza, Nicole; Cox, Lisa; Harrison, Carrie; Neumeister, Michael W

    2016-02-01

    Recent literature has shown that full-thickness wounds, devoid of the stem cell niche, can subsequently be reconstructed with functional skin elements following migration of the LGR6 epithelial stem cell into the wound bed. In this study, the authors use a variety of LGR6 epithelial stem cell-seeded scaffolds to determine therapeutic utility and regenerative potential in the immediate reconstruction of full-thickness wounds. Isolated LGR6 epithelial stem cells were seeded onto a spectrum of acellular matrices and monitored in both in vitro and in vivo settings to determine their relative capacity to regenerate tissues and heal wounds. Wound beds containing LGR6 stem cell-seeded scaffolds showed significantly augmented rates of healing, epithelialization, and hair growth compared with controls. Gene and proteomic expression studies indicate that LGR6 stem cell-seeded constructs up-regulate WNT, epidermal growth factor, and angiogenesis pathways. Finally, the addition of stromal vascular fraction to LGR6 stem cell-seeded constructs induces polarized tissue formation, nascent hair growth, and angiogenesis within wounds. LGR6 stem cells are able to undergo proliferation, differentiation, and migration following seeding onto a variety of collagen-based scaffolding. In addition, deployment of these constructs induces epithelialization, hair growth, and angiogenesis within wound beds. The addition of stromal vascular fraction to LGR6 stem cell-containing scaffolds initiated an early form of tissue polarization, providing for the first time a clinically applicable stem cell-based construct that is capable of the repair of full-thickness wounds and hair regeneration. Therapeutic, V.

  13. Advances of mesenchymal stem cells derived from bone marrow and dental tissue in craniofacial tissue engineering.

    Science.gov (United States)

    Yang, Maobin; Zhang, Hongming; Gangolli, Riddhi

    2014-05-01

    Bone and dental tissues in craniofacial region work as an important aesthetic and functional unit. Reconstruction of craniofacial tissue defects is highly expected to ensure patients to maintain good quality of life. Tissue engineering and regenerative medicine have been developed in the last two decades, and been advanced with the stem cell technology. Bone marrow derived mesenchymal stem cells are one of the most extensively studied post-natal stem cell population, and are widely utilized in cell-based therapy. Dental tissue derived mesenchymal stem cells are a relatively new stem cell population that isolated from various dental tissues. These cells can undergo multilineage differentiation including osteogenic and odontogenic differentiation, thus provide an alternative source of mesenchymal stem cells for tissue engineering. In this review, we discuss the important issues in mesenchymal stem cell biology including the origin and functions of mesenchymal stem cells, compare the properties of these two types of mesenchymal cells, update recent basic research and clinic applications in this field, and address important future challenges.

  14. DEFECTS SIMULATION OF ROLLING STRIP

    OpenAIRE

    Rudolf Mišičko; Tibor Kvačkaj; Martin Vlado; Lucia Gulová; Miloslav Lupták; Jana Bidulská

    2009-01-01

    The defects in the continuous casting slabs can be developed or kept down in principle by rolling technology, especially depend to sort, size and distribution of primary defects, as well as used of rolling parameters. Scope of the article is on observation behavior artificial surface and undersurface defects (scores) without filler (surface defects) and filling by oxides and casting powder (subsurface defects). First phase of hot rolling process have been done by software simulation DEFORM 3D...

  15. The application of digital surgical diagnosis and treatment technology: a promising strategy for surgical reconstruction of craniomaxillofacial defect and deformity.

    Science.gov (United States)

    Wang, Li-ya; Du, Hong-ming; Zhang, Gang; Tang, Wei; Liu, Lei; Jing, Wei; Long, Jie

    2011-12-01

    The craniomaxillofacial defect and deformity always leads to serious dysfunction in mastication and facial contour damage, significantly reducing patients' quality of life. However, surgical reconstruction of a craniomaxillofacial hard tissue defect or deformity is extremely complex and often does not result in desired facial morphology. Improving the result for patients with craniomaxillofacial defect and deformity remains a challenge for surgeons. Using digital technology for surgical diagnosis and treatment may help solve this problem. Computer-assisted surgical technology and surgical navigation technology are included in the accurate digital diagnosis and treatment system we propose. These technologies will increase the accuracy of the design of the operation plan. In addition, the intraoperative real-time navigating location system controlling the robotic arm or advanced intelligent robot will provide accurate, individualized surgical treatment for patients. Here we propose the hypothesis that a digital surgical diagnosis and treatment technology may provide a new approach for precise surgical reconstruction of complicated craniomaxillofacial defect and deformity. Our hypothesis involves modern digital surgery, a three-dimensional navigation surgery system and modern digital imaging technology, and our key aim is to establish a technological platform for customized digital surgical design and surgical navigation for craniomaxillofacial defect and deformity. If the hypothesis is proven practical, this novel therapeutic approach could improve the result of surgical reconstruction for craniomaxillofacial defect and deformity for many patients. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Computational mask defect review for contamination and haze inspections

    Science.gov (United States)

    Morgan, Paul; Rost, Daniel; Price, Daniel; Corcoran, Noel; Satake, Masaki; Hu, Peter; Peng, Danping; Yonenaga, Dean; Tolani, Vikram; Wolf, Yulian; Shah, Pinkesh

    2013-09-01

    the mask manufacturing process. The latter characterization qualifies real defect signatures, such as pin-dots or pin-holes, extrusions or intrusions, assist-feature or dummy-fill defects, writeerrors or un-repairable defects, chrome-on-shifter or missing chrome-from-shifter defects, particles, etc., and also false defect signatures, such as those due to inspection tool registration or image alignment, interlace artifacts, CCD camera artifacts, optical shimmer, focus errors, etc. Such qualitative characterization of defects has enabled better inspection tool SPC and process defect control in the mask shop. In this paper, the same computational approach to defect review has been extended to contamination style defect inspections, including Die-to-Die reflected, and non Die-to-Die or single-die inspections. In addition to the computational methods used for transmitted aerial images, defects detected in die-to-die reflected light mode are analyzed based on special defect and background coloring in reflected-light, and other characteristics to determine the exact type and severity. For those detected in the non Die-to-Die mode, only defect images are available from the inspection tool. Without a reference, i.e., defect-free image, it is often difficult to determine the true nature or impact of the defect in question. Using a combination of inspection-tool modeling and image inversion techniques, Luminescent's LAIPHTM system generates an accurate reference image, and then proceeds with automated defect characterization as if the images were simply from a die-to-die inspection. The disposition of contamination style defects this way, filters out >90% of false and nuisance defects that otherwise would have been manually reviewed or measured on AIMSTM. Such computational defect review, unifying defect disposition across all available inspection modes, has been imperative to ensuring no yield losses due to errors in operator defect classification on one hand, and on the other

  17. Quantum computing with defects

    Science.gov (United States)

    Varley, Joel

    2011-03-01

    The development of a quantum computer is contingent upon the identification and design of systems for use as qubits, the basic units of quantum information. One of the most promising candidates consists of a defect in diamond known as the nitrogen-vacancy (NV-1) center, since it is an individually-addressable quantum system that can be initialized, manipulated, and measured with high fidelity at room temperature. While the success of the NV-1 stems from its nature as a localized ``deep-center'' point defect, no systematic effort has been made to identify other defects that might behave in a similar way. We provide guidelines for identifying other defect centers with similar properties. We present a list of physical criteria that these centers and their hosts should meet and explain how these requirements can be used in conjunction with electronic structure theory to intelligently sort through candidate systems. To elucidate these points, we compare electronic structure calculations of the NV-1 center in diamond with those of several deep centers in 4H silicon carbide (SiC). Using hybrid functionals, we report formation energies, configuration-coordinate diagrams, and defect-level diagrams to compare and contrast the properties of these defects. We find that the NC VSi - 1 center in SiC, a structural analog of the NV-1 center in diamond, may be a suitable center with very different optical transition energies. We also discuss how the proposed criteria can be translated into guidelines to discover NV analogs in other tetrahedrally coordinated materials. This work was performed in collaboration with J. R. Weber, W. F. Koehl, B. B. Buckley, A. Janotti, C. G. Van de Walle, and D. D. Awschalom. This work was supported by ARO, AFOSR, and NSF.

  18. Structure defects in cementite

    International Nuclear Information System (INIS)

    Schmitt, Bernard

    1971-01-01

    After a presentation of experimental techniques (elaboration principles, elaboration techniques, and investigation techniques for cementite thin layers and iron-carbon massive alloys), the author of this research thesis reports the study of cementite structure (interatomic distance, description and representation), reports the study of iron-carbon thin layers (structure, influence of silicon, defects), reports the study of perfect and imperfect dislocations and of plane defects in cementite. The author also reports hardness measurements, and discusses the relationships between cementite and other iron carbides

  19. Mandibular reconstruction with composite microvascular tissue transfer

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, J.J. III; Wooden, W.A. (Emory Univ. School of Medicine, Atlanta, GA (USA))

    1990-10-01

    Microvascular free tissue transfer has provided a variety of methods of restoring vascularized bone and soft tissue to difficult defects created by tumor resection and trauma. Over 7 years, 26 patients have undergone 28 free flaps for mandibular reconstruction, 15 for primary squamous cell carcinoma of the floor of the mouth or tongue, 7 for recurrent tumor, and 6 for other reasons (lymphangioma (1), infection (1), gunshot wound (1), and osteoradionecrosis (3)). Primary reconstruction was performed in 19 cases and secondary in 9. All repairs were composite flaps including 12 scapula, 5 radial forearm, 3 fibula, 2 serratus, and 6 deep circumflex iliac artery. Mandibular defects included the symphysis alone (7), symphysis and body (5), symphysis-body-ramus condyle (2), body or ramus (13), and bilateral body (1). Fourteen patients had received prior radiotherapy to adjuvant or curative doses. Eight received postoperative radiotherapy. All patients had initially successful vascularized reconstruction by clinical examination (28) and positive radionuclide scan (22 of 22). Bony stability was achieved in 25 of 26 patients and oral continence in 24 of 26. One complete flap loss occurred at 14 days. Complications of some degree developed in 22 patients including partial skin necrosis (3), orocutaneous fistula (3), plate exposure (1), donor site infection (3), fracture of reconstruction (1), and fracture of the radius (1). Microvascular transfer of bone and soft tissue allows a reliable reconstruction--despite previous radiotherapy, infection, foreign body, or surgery--in almost every situation in which mandible and soft tissue are absent. Bony union, a healed wound, and reasonable function and appearance are likely despite early fistula, skin loss, or metal plate or bone exposure.

  20. Quantum computing with defects.

    Science.gov (United States)

    Weber, J R; Koehl, W F; Varley, J B; Janotti, A; Buckley, B B; Van de Walle, C G; Awschalom, D D

    2010-05-11

    Identifying and designing physical systems for use as qubits, the basic units of quantum information, are critical steps in the development of a quantum computer. Among the possibilities in the solid state, a defect in diamond known as the nitrogen-vacancy (NV(-1)) center stands out for its robustness--its quantum state can be initialized, manipulated, and measured with high fidelity at room temperature. Here we describe how to systematically identify other deep center defects with similar quantum-mechanical properties. We present a list of physical criteria that these centers and their hosts should meet and explain how these requirements can be used in conjunction with electronic structure theory to intelligently sort through candidate defect systems. To illustrate these points in detail, we compare electronic structure calculations of the NV(-1) center in diamond with those of several deep centers in 4H silicon carbide (SiC). We then discuss the proposed criteria for similar defects in other tetrahedrally coordinated semiconductors.

  1. Defects in semiconductor nanostructures

    Indian Academy of Sciences (India)

    sizes were less than 100 Si atoms due to computational limitations. An interesting parallel is that current first principles calculations alluded to in §5 are size ham- pered for similar reasons. These 'defect molecule' calculations were probably the first studies in SN. We believe that a perusal of this 'ancient' scientific literature.

  2. Production of point defects

    International Nuclear Information System (INIS)

    Zuppiroli, L.

    1975-01-01

    Vacancies at thermodynamic equilibrium and the annealing of these defects are studied first, after which electron irradiations are dealt with. The displacement threshold energy concept is introduced. Part three concerns heavy ion and neutron irradiations. Displacement cascades and the thermal spike concept are discussed [fr

  3. Fetal abdominal wall defects.

    Science.gov (United States)

    Prefumo, Federico; Izzi, Claudia

    2014-04-01

    The most common fetal abdominal wall defects are gastroschisis and omphalocele, both with a prevalence of about three in 10,000 births. Prenatal ultrasound has a high sensitivity for these abnormalities already at the time of the first-trimester nuchal scan. Major unrelated defects are associated with gastroschisis in about 10% of cases, whereas omphalocele is associated with chromosomal or genetic abnormalities in a much higher proportion of cases. Challenges in management of gastroschisis are related to the prevention of late intrauterine death, and the prediction and treatment of complex forms. With omphalocele, the main difficulty is the exclusion of associated conditions, not all diagnosed prenatally. An outline of the postnatal treatment of abdominal wall defects is given. Other rarer forms of abdominal wall defects are pentalogy of Cantrell, omphalocele, bladder exstrophy, imperforate anus, spina bifida complex, prune-belly syndrome, body stalk anomaly, and bladder and cloacal exstrophy; they deserve multidisciplinary counselling and management. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Defects in flexoelectric solids

    Science.gov (United States)

    Mao, Sheng; Purohit, Prashant K.

    2015-11-01

    A solid is said to be flexoelectric when it polarizes in proportion to strain gradients. Since strain gradients are large near defects, we expect the flexoelectric effect to be prominent there and decay away at distances much larger than a flexoelectric length scale. Here, we quantify this expectation by computing displacement, stress and polarization fields near defects in flexoelectric solids. For point defects we recover some well known results from strain gradient elasticity and non-local piezoelectric theories, but with different length scales in the final expressions. For edge dislocations we show that the electric potential is a maximum in the vicinity of the dislocation core. We also estimate the polarized line charge density of an edge dislocation in an isotropic flexoelectric solid which is in agreement with some measurements in ice. We perform an asymptotic analysis of the crack tip fields in flexoelectric solids and show that our results share some features from solutions in strain gradient elasticity and piezoelectricity. We also compute the energy release rate for cracks using simple crack face boundary conditions and use them in classical criteria for crack growth to make predictions. Our analysis can serve as a starting point for more sophisticated analytic and computational treatments of defects in flexoelectric solids which are gaining increasing prominence in the field of nanoscience and nanotechnology.

  5. Semiconductor Nanowires: Defects Update

    Science.gov (United States)

    Kavanagh, Karen L.

    2008-05-01

    Structural defects commonly observed in semiconducting nanowires by electron microscopy will be reviewed and their origins discussed. Their effects on electrical and optical properties will be illustrated with examples from GaSb, InAs, and ZnSe nanowires grown by MOCVD and MBE.

  6. Regenerative potential of tonsil mesenchymal stem cells on surgical cutaneous defect.

    Science.gov (United States)

    Shin, Sung-Chan; Seo, Yoojin; Park, Hee Young; Jung, Da-Woon; Shin, Tae-Hoon; Son, Haejin; Kim, Young Keum; Lee, Jin-Choon; Sung, Eui-Suk; Jang, Jeon Yeob; Kim, Hyung-Sik; Lee, Byung-Joo

    2018-02-07

    As tissue engineering and regenerative medicine have evolved recently, stem cell therapy has been investigated in the field of impaired wound healing. Several studies have reported that mesenchymal stem cells derived from various tissues including bone marrow and adipose tissue can exert the regenerative efficacy in the wound healing. Previously, we have demonstrated the isolation and characterization of tonsil-derived mesenchymal stem cells (TMSCs) with excellent proliferative property. In the present study, we aimed to evaluate the regenerative efficacy of TMSCs in the wound healing process. Two distinct cutaneous surgical defects were generated in the dorsum of mice. Each wound was treated with TMSCs or phosphate-buffered saline (PBS), respectively. After sacrifice, the skin and subcutaneous tissues around the surgical defect were harvested and assessed for inflammation, re-epithelialization, dermal regeneration, and granulation tissue formation. The administration of TMSCs into wound beds significantly promoted the repair of surgical defects in mice. Especially, TMSCs efficiently contributed to the attenuation of excessive inflammation in the surgical lesion, as well as the augmentation of epidermal and dermal regeneration. To elucidate the underlying mechanisms, TMSCs were analyzed for their potency in immunomodulatory ability on immune cells, stimulatory effect on the proliferation of keratinocytes, and fibroblasts, as well as the regulation of fibroblast differentiation. TMSCs inhibited the non-specific or T-cell-specific proliferation of peripheral blood mononuclear cells, as well as the M1 polarization of macrophage-like cells. Moreover, TMSCs augmented the proliferation of skin-constituting fibroblasts and keratinocytes while they suppressed the differentiation of fibroblasts into myofibroblasts. Taken together, our findings demonstrate the regenerative potential of TMSCs in wound healing process through the regulation on inflammation, proliferation

  7. Cranial Defects and Cranioplasty. Part 8. Chapter 194,

    Science.gov (United States)

    1984-01-01

    skull. That such tissue is quantitatively unavailable explains the search for an acceptable albeit imperfect substitute. An ideal material would be...deficiency of periosteum from skull to form bone (55, 56). Isolated periosteum of tibia over tibial defects had 7 times the potency for osteogenesis ...Folkman J, Mulliken JB: Application of the biological principle of induced osteogenesis for craniofacial I. defects. Lancet 1:959-963, 1981. 18. Grant

  8. Reconstruction of Alar Nasal Cartilage Defects Using a Tissue Engineering Technique Based on a Combined Use of Autologous Chondrocyte Micrografts and Platelet-rich Plasma: Preliminary Clinical and Instrumental Evaluation

    Science.gov (United States)

    Scioli, Maria G.; Bielli, Alessandra; Orlandi, Augusto; Cervelli, Valerio

    2016-01-01

    Background: Developing cartilage constructs with injectability, appropriate matrix composition, and persistent cartilaginous phenotype remains an enduring challenge in cartilage repair. The combined use of autologous chondrocyte micrografts and platelet-rich plasma (PRP) is an alternative that opens a new era in this field. Methods: At the Department of Plastic and Reconstructive Surgery, University of Rome Tor Vergata, Italy, 11 patients underwent nasal alar reconstruction with chondrocyte micrografts gently poured onto PRP in solid form. A computed tomographic scan control was performed after 12 months. Pearson’s Chi-square test was used to investigate difference in cartilage density between native and newly formed cartilages. Results: The constructs of chondrocyte micrografts–PRP that were subcutaneously injected resulted in a persistent cartilage tissue with appropriate morphology, adequate central nutritional perfusion without central necrosis or ossification, and further augmented nasal dorsum without obvious contraction and deformation. Conclusion: This report demonstrated that chondrocyte micrografts derived from nasal septum poured onto PRP in solid form are useful for cartilage regeneration in patients with external nasal valve collapse. PMID:27826462

  9. A clinical case of single-stage correction of penetration combined orofacial defect with two microsurgical autografts

    Directory of Open Access Journals (Sweden)

    A. D. Kaprin

    2015-01-01

    Full Text Available After surgical treatment for locally advanced oral tumors with resection of soft tissues, mucosal membrane, and facial skeletal structures, there are penetration combined defects, removal of which is a challenge for reconstructive surgeons. Mandibular repair is one of the problems in the correction of combined oral defects. Surgeons use different grafts to remove mandibular defects. One-flap transplantation does not always solve all reconstruction problems and ensure the repair of the mucosal membrane, a soft-tissue component, skin integuments, and facial skeleton.The authors describe a clinical case of successful single-stage correction of penetration combined orofacial defect after resection of the tongue, mouth floor, en bloc resection of the lower jaw and mental soft tissues, bilateral cervical supramyochoroidal lymphadenectomy, stage LCL CM mandibular defect formation after J. Boyd, by using two microsurgical autografts (a peroneal skin-muscle-skin autograft and a radial skin-fascia one in a 39-year-old female patient clinically diagnosed with carcinoma of the left mandibular alveolar ridge mucosa, Stage IVA (T4аN0M0.The Department of Microsurgery, P.A. Herzen Moscow Oncology Research Institute, Ministry of Health of Russia, has gained experience in comprehensively correcting extensive combined maxillofacial defects with two or more grafts in 27 patients who underwent autografting with a total of 73 flaps. The most functionally incapacitating and life-incompatible defect was removed at Stage 1 of reconstructive treatment. Delayed reconstruction was made after a complex of specialized antitumor therapy and assessment of treatment results in the absence of progressive growth. A great problem during multi-stage defect correction is presented by the lack of recipient vessels after cervical lymphadenectomy, the presence of soft tissue scar changes, trismus, temporomandibular joint ankylosis, contractures and displacement of the edges of the

  10. Reduction in Defect Content of ODS Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ritherdon, J

    2001-05-15

    The work detailed within this report is a continuation of earlier work carried out under contract number 1DX-SY382V. The earlier work comprises a literature review of the sources and types of defects found principally in Fe-based ODS alloys as well as experimental work designed to identify defects in the prototype ODS-Fe{sub 3}Al alloy, deduce their origins and to recommend methods of defect reduction. The present work is an extension of the experimental work already reported and concentrates on means of reduction of defects already identified rather than the search for new defect types. This report also includes results gathered during powder separation trials, conducted by the University of Groningen, Netherlands and coordinated by the University of Liverpool, involving the separation of different metallic powders in terms of their differing densities. The scope and objectives of the present work were laid out in the technical proposal ''Reduction in Defect Content in ODS Alloys-III''. All the work proposed in the ''Statement of Work'' section of the technical proposal has been carried out and all work extra to the ''Statement of Work'' falls within the context of an ODS-Fe{sub 3}Al alloy of improved overall quality and potential creep performance in the consolidated form. The outturn of the experimental work performed is reported in the following sections.

  11. The reading man flap for closure of large meningomyelocele defects.

    Science.gov (United States)

    Mutaf, Mehmet; Temel, Metin; Günal, Ertan

    2012-05-01

    Closure of the skin defect in myelomeningocele repair is an essential step that determines the quality of the surgical result. In large myelomeningoceles, however, adequate skin coverage may not be accomplished by direct closure or skin undermining. In such cases, the skin defect is best repaired using flaps. The aim of this study is to evaluate the reading man procedure for closure of large meningomyelocele defect. In this procedure, after neurosurgical repair and closure of the placode, the defect surgically becomes a circle in shape. Then, the circular defect is closed by transposition of two skin flaps designed in an unequal Z-plasty manner. Over 5 years, the reading man procedure was used for closure of large meningomyelocele defects in seven patients (four females and three males), aged between 1.5 and 6 months. The defect size was 10.5×7.25 cm (8.5×5.3 and 12.6×9.5 cm) on average. The localisation of the lesions was thoracolumbar in two patients and lumbosacral in five patients. In all patients, a successful tension-free one-stage closure was obtained without dog-ear formation. Except for one patient with minimal tip necrosis, healing was uneventful without any complications. There was no patient with late breakdown of the wound during 1.5 years (8 months-4 years) of mean follow-up. The reading man procedure enables the surgeon to achieve a tension-free defect closure of considerably large meningomyeleocele defects. Using two well-vascularised fasciocutaneous flaps, it provides a durable coverage and soft tissue padding over the neural tissues with no suture seam at midline. With these advantages, the Reading Man Procedure seems to be a useful and safe alternative for closure of large meningomyelocele defects. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  12. Maternal autoimmune disease and birth defects in the National Birth Defects Prevention Study.

    Science.gov (United States)

    Howley, Meredith M; Browne, Marilyn L; Van Zutphen, Alissa R; Richardson, Sandra D; Blossom, Sarah J; Broussard, Cheryl S; Carmichael, Suzan L; Druschel, Charlotte M

    2016-11-01

    Little is known about the association between maternal autoimmune disease or its treatment and the risk of birth defects. We examined these associations using data from the National Birth Defects Prevention Study, a multi-site, population-based, case-control study. Analyses included 25,116 case and 9897 unaffected control infants with estimated delivery dates between 1997 and 2009. Information on autoimmune disease, medication use, and other pregnancy exposures was collected by means of telephone interview. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for birth defects with five or more exposed cases; crude ORs and exact 95% CIs were estimated for birth defects with three to four exposed cases. Autoimmune disease was reported by 373 mothers (279 case and 94 control mothers). The majority of birth defects evaluated were not associated with autoimmune disease; however, a statistically significant association between maternal autoimmune disease and encephalocele was observed (OR, 4.64; 95% CI, 1.95-11.04). Eighty-two mothers with autoimmune disease used an immune modifying/suppressing medication during pregnancy; this was associated with encephalocele (OR, 7.26; 95% CI, 1.37-24.61) and atrial septal defects (OR, 3.01; 95% CI, 1.16-7.80). Our findings suggest maternal autoimmune disease and treatment are not associated with the majority of birth defects, but may be associated with some defects, particularly encephalocele. Given the low prevalence of individual autoimmune diseases and the rare use of specific medications, we were unable to examine associations of specific autoimmune diseases and medications with birth defects. Other studies are needed to confirm these findings. Birth Defects Research (Part A) 106:950-962, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  13. Ethanol exposure disrupts extraembryonic microtubule cytoskeleton and embryonic blastomere cell adhesion, producing epiboly and gastrulation defects

    Directory of Open Access Journals (Sweden)

    Swapnalee Sarmah

    2013-08-01

    Fetal alcohol spectrum disorder (FASD occurs when pregnant mothers consume alcohol, causing embryonic ethanol exposure and characteristic birth defects that include craniofacial, neural and cardiac defects. Gastrulation is a particularly sensitive developmental stage for teratogen exposure, and zebrafish is an outstanding model to study gastrulation and FASD. Epiboly (spreading blastomere cells over the yolk cell, prechordal plate migration and convergence/extension cell movements are sensitive to early ethanol exposure. Here, experiments are presented that characterize mechanisms of ethanol toxicity on epiboly and gastrulation. Epiboly mechanisms include blastomere radial intercalation cell movements and yolk cell microtubule cytoskeleton pulling the embryo to the vegetal pole. Both of these processes were disrupted by ethanol exposure. Ethanol effects on cell migration also indicated that cell adhesion was affected, which was confirmed by cell aggregation assays. E-cadherin cell adhesion molecule expression was not affected by ethanol exposure, but E-cadherin distribution, which controls epiboly and gastrulation, was changed. E-cadherin was redistributed into cytoplasmic aggregates in blastomeres and dramatically redistributed in the extraembryonic yolk cell. Gene expression microarray analysis was used to identify potential causative factors for early development defects, and expression of the cell adhesion molecule protocadherin-18a (pcdh18a, which controls epiboly, was significantly reduced in ethanol exposed embryos. Injecting pcdh18a synthetic mRNA in ethanol treated embryos partially rescued epiboly cell movements, including enveloping layer cell shape changes. Together, data show that epiboly and gastrulation defects induced by ethanol are multifactorial, and include yolk cell (extraembryonic tissue microtubule cytoskeleton disruption and blastomere adhesion defects, in part caused by reduced pcdh18a expression.

  14. Ventricular Septal Defect (For Teens)

    Science.gov (United States)

    ... have a heart defect should avoid getting body piercings. Piercing increases the possibility that bacteria can get into ... damage heart valves. If you're considering a piercing and you have a heart defect, talk to ...

  15. Congenital Heart Defects (For Parents)

    Science.gov (United States)

    ... diagnosed until the teen years — or even adulthood. Newborn Screening Newborns in the U.S. are screened at ... Has a Heart Defect Coarctation of the Aorta Arrhythmias Mitral Valve Prolapse Atrial Septal Defect Ventricular Septal ...

  16. Defects in Quantum Computers.

    Science.gov (United States)

    Gardas, Bartłomiej; Dziarmaga, Jacek; Zurek, Wojciech H; Zwolak, Michael

    2018-03-14

    The shift of interest from general purpose quantum computers to adiabatic quantum computing or quantum annealing calls for a broadly applicable and easy to implement test to assess how quantum or adiabatic is a specific hardware. Here we propose such a test based on an exactly solvable many body system-the quantum Ising chain in transverse field-and implement it on the D-Wave machine. An ideal adiabatic quench of the quantum Ising chain should lead to an ordered broken symmetry ground state with all spins aligned in the same direction. An actual quench can be imperfect due to decoherence, noise, flaws in the implemented Hamiltonian, or simply too fast to be adiabatic. Imperfections result in topological defects: Spins change orientation, kinks punctuating ordered sections of the chain. The number of such defects quantifies the extent by which the quantum computer misses the ground state, and is, therefore, imperfect.

  17. Computer experiment studies on mechanisms for irradiation induced defect production and annealing processes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Beeler, J.R. Jr.; Beeler, M.F.

    1979-06-01

    This research is based on pair potentials used in the Brookhaven work. It extends their use in defect production simulations to the 5 MeV range and characterizes the short term annealing of the primary defect states. Defect properties and interactions are studied. Defect interactions include carbon, helium, and misfit metallic substitutional impurity interactions with vacancy and interstitial defects as well as vacancy-vacancy, interstitial-interstitial and vacancy-interstitial interactions. (FS)

  18. Computer experiment studies on mechanisms for irradiation induced defect production and annealing processes. Final report

    International Nuclear Information System (INIS)

    Beeler, J.R. Jr.; Beeler, M.F.

    1979-06-01

    This research is based on pair potentials used in the Brookhaven work. It extends their use in defect production simulations to the 5 MeV range and characterizes the short term annealing of the primary defect states. Defect properties and interactions are studied. Defect interactions include carbon, helium, and misfit metallic substitutional impurity interactions with vacancy and interstitial defects as well as vacancy-vacancy, interstitial-interstitial and vacancy-interstitial interactions

  19. Ultrasonic NDE Simulation for Composite Manufacturing Defects

    Science.gov (United States)

    Leckey, Cara A. C.; Juarez, Peter D.

    2016-01-01

    The increased use of composites in aerospace components is expected to continue into the future. The large scale use of composites in aerospace necessitates the development of composite-appropriate nondestructive evaluation (NDE) methods to quantitatively characterize defects in as-manufactured parts and damage incurred during or post manufacturing. Ultrasonic techniques are one of the most common approaches for defect/damage detection in composite materials. One key technical challenge area included in NASA's Advanced Composite's Project is to develop optimized rapid inspection methods for composite materials. Common manufacturing defects in carbon fiber reinforced polymer (CFRP) composites include fiber waviness (in-plane and out-of-plane), porosity, and disbonds; among others. This paper is an overview of ongoing work to develop ultrasonic wavefield based methods for characterizing manufacturing waviness defects. The paper describes the development and implementation of a custom ultrasound simulation tool that is used to model ultrasonic wave interaction with in-plane fiber waviness (also known as marcelling). Wavefield data processing methods are applied to the simulation data to explore possible routes for quantitative defect characterization.

  20. Computational model-informed design and bioprinting of cell-patterned constructs for bone tissue engineering.

    Science.gov (United States)

    Carlier, Aurélie; Skvortsov, Gözde Akdeniz; Hafezi, Forough; Ferraris, Eleonora; Patterson, Jennifer; Koç, Bahattin; Van Oosterwyck, Hans

    2016-05-17

    Three-dimensional (3D) bioprinting is a rapidly advancing tissue engineering technology that holds great promise for the regeneration of several tissues, including bone. However, to generate a successful 3D bone tissue engineering construct, additional complexities should be taken into account such as nutrient and oxygen delivery, which is often insufficient after implantation in large bone defects. We propose that a well-designed tissue engineering construct, that is, an implant with a specific spatial pattern of cells in a matrix, will improve the healing outcome. By using a computational model of bone regeneration we show that particular cell patterns in tissue engineering constructs are able to enhance bone regeneration compared to uniform ones. We successfully bioprinted one of the most promising cell-gradient patterns by using cell-laden hydrogels with varying cell densities and observed a high cell viability for three days following the bioprinting process. In summary, we present a novel strategy for the biofabrication of bone tissue engineering constructs by designing cell-gradient patterns based on a computational model of bone regeneration, and successfully bioprinting the chosen design. This integrated approach may increase the success rate of implanted tissue engineering constructs for critical size bone defects and also can find a wider application in the biofabrication of other types of tissue engineering constructs.

  1. Benign gastric filling defect

    Energy Technology Data Exchange (ETDEWEB)

    Oh, K. K.; Lee, Y. H.; Cho, O. K.; Park, C. Y. [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1979-06-15

    The gastric lesion is a common source of complaints to Orientals, however, evaluation of gastric symptoms and laboratory examination offer little specific aid in the diagnosis of gastric diseases. Thus roentgenography of gastrointestinal tract is one of the most reliable method for detail diagnosis. On double contract study of stomach, gastric filling defect is mostly caused by malignant gastric cancer, however, other benign lesions can cause similar pictures which can be successfully treated by surgery. 66 cases of benign causes of gastric filling defect were analyzed at this point of view, which was verified pathologically by endoscope or surgery during recent 7 years in Yensei University College of Medicine, Severance Hospital. The characteristic radiological picture of each disease was discussed for precise radiologic diagnosis. 1. Of total 66 cases, there were 52 cases of benign gastric tumor 10 cases of gastric varices, 5 cases of gastric bezoar, 5 cases of corrosive gastritis, 3 cases of granulomatous disease and one case of gastric hematoma. 2. The most frequent causes of benign tumors were adenomatous polyp (35/42) and the next was leiomyoma (4/42). Others were one of case of carcinoid, neurofibroma and cyst. 3. Characteristic of benign adenomatous polyp were relatively small in size, smooth surface and were observed that large size, benign polyp was frequently type IV lesion with a stalk. 4. Submucosal tumors such as leiomyoma needed differential diagnosis with polypoid malignant cancer. However, the characteristic points of differentiation was well circumscribed smooth margined filling defect without definite mucosal destruction on surface. 5. Gastric varices showed multiple lobulated filling defected especially on gastric fundus that changed its size and shape by respiration and posture of patients. Same varices lesions on esophagus and history of liver disease were helpful for easier diagnosis. 6. Gastric bezoar showed well defined movable mass

  2. Benign gastric filling defect

    International Nuclear Information System (INIS)

    Oh, K. K.; Lee, Y. H.; Cho, O. K.; Park, C. Y.

    1979-01-01

    The gastric lesion is a common source of complaints to Orientals, however, evaluation of gastric symptoms and laboratory examination offer little specific aid in the diagnosis of gastric diseases. Thus roentgenography of gastrointestinal tract is one of the most reliable method for detail diagnosis. On double contract study of stomach, gastric filling defect is mostly caused by malignant gastric cancer, however, other benign lesions can cause similar pictures which can be successfully treated by surgery. 66 cases of benign causes of gastric filling defect were analyzed at this point of view, which was verified pathologically by endoscope or surgery during recent 7 years in Yensei University College of Medicine, Severance Hospital. The characteristic radiological picture of each disease was discussed for precise radiologic diagnosis. 1. Of total 66 cases, there were 52 cases of benign gastric tumor 10 cases of gastric varices, 5 cases of gastric bezoar, 5 cases of corrosive gastritis, 3 cases of granulomatous disease and one case of gastric hematoma. 2. The most frequent causes of benign tumors were adenomatous polyp (35/42) and the next was leiomyoma (4/42). Others were one of case of carcinoid, neurofibroma and cyst. 3. Characteristic of benign adenomatous polyp were relatively small in size, smooth surface and were observed that large size, benign polyp was frequently type IV lesion with a stalk. 4. Submucosal tumors such as leiomyoma needed differential diagnosis with polypoid malignant cancer. However, the characteristic points of differentiation was well circumscribed smooth margined filling defect without definite mucosal destruction on surface. 5. Gastric varices showed multiple lobulated filling defected especially on gastric fundus that changed its size and shape by respiration and posture of patients. Same varices lesions on esophagus and history of liver disease were helpful for easier diagnosis. 6. Gastric bezoar showed well defined movable mass

  3. Nanotechnology in bone tissue engineering.

    Science.gov (United States)

    Walmsley, Graham G; McArdle, Adrian; Tevlin, Ruth; Momeni, Arash; Atashroo, David; Hu, Michael S; Feroze, Abdullah H; Wong, Victor W; Lorenz, Peter H; Longaker, Michael T; Wan, Derrick C

    2015-07-01

    Nanotechnology represents a major frontier with potential to significantly advance the field of bone tissue engineering. Current limitations in regenerative strategies include impaired cellular proliferation and differentiation, insufficient mechanical strength of scaffolds, and inadequate production of extrinsic factors necessary for efficient osteogenesis. Here we review several major areas of research in nanotechnology with potential implications in bone regeneration: 1) nanoparticle-based methods for delivery of bioactive molecules, growth factors, and genetic material, 2) nanoparticle-mediated cell labeling and targeting, and 3) nano-based scaffold construction and modification to enhance physicochemical interactions, biocompatibility, mechanical stability, and cellular attachment/survival. As these technologies continue to evolve, ultimate translation to the clinical environment may allow for improved therapeutic outcomes in patients with large bone deficits and osteodegenerative diseases. Traditionally, the reconstruction of bony defects has relied on the use of bone grafts. With advances in nanotechnology, there has been significant development of synthetic biomaterials. In this article, the authors provided a comprehensive review on current research in nanoparticle-based therapies for bone tissue engineering, which should be useful reading for clinicians as well as researchers in this field. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. [Experimental study of repairing full-thickness articular cartilage defect with chondrocyte-sodium alginate hydrogel-SIS complex].

    Science.gov (United States)

    Mo, Xiangtao; Deng, Li; Li, Xiuqun; Xie, Huiqi; Luo, Jingcong; Guo, Shangchun; Yang, Zhiming

    2009-08-01

    To explore the effect of tissue engineered cartilage reconstructed by using sodium alginate hydrogel and SIS complex as scaffold material and chondrocyte as seed cell on the repair of full-thickness articular cartilage defects. SIS was prepared by custom-made machine and detergent-enzyme treatment. Full-thickness articular cartilage of loading surface of the humeral head and the femoral condyle obtained from 8 New Zealand white rabbits (2-3 weeks old) was used to culture chondrocytes in vitro. Rabbit chondrocytes at passage 4 cultured by conventional multiplication method were diluted by sodium alginate to (5-7) x 10(7) cells/mL, and then were coated on SIS to prepare chondrocyte-sodium alginate hydrogel-SIS complex. Forty 6-month-old clean grade New Zealand white rabbits weighing 3.0-3.5 kg were randomized into two groups according to different operative methods (n = 20 rabbits per group), and full-thickness cartilage defect model of the unilateral knee joint (right or left) was established in every rabbit. In experimental group, the complex was implanted into the defect layer by layer to construct tissue engineered cartilage, and SIS membrane was coated on the surface to fill the defect completely. While in control group, the cartilage defect was filled by sodium alginate hydrogel and was sutured after being coated with SIS membrane without seeding of chondrocyte. General condition of the rabbits after operation was observed. The rabbits in two groups were killed 1, 3, 5, 7, and 9 months after operation, and underwent gross and histology observation. Eight rabbits were excluded due to anesthesia death, wound infection and diarrhea death. Sixteen rabbits per group were included in the experiment, and 3, 3, 3, 3, and 4 rabbits from each group were randomly selected and killed 1, 3, 5, 7, and 9 months after operation, respectively. Gross observation and histology Masson trichrome staining: in the experimental group, SIS on the surface of the implant was fused with

  5. Risk factors for pedicled flap necrosis in hand soft tissue reconstruction: a multivariate logistic regression analysis.

    Science.gov (United States)

    Gong, Xu; Cui, Jianli; Jiang, Ziping; Lu, Laijin; Li, Xiucun

    2018-03-01

    Few clinical retrospective studies have reported the risk factors of pedicled flap necrosis in hand soft tissue reconstruction. The aim of this study was to identify non-technical risk factors associated with pedicled flap perioperative necrosis in hand soft tissue reconstruction via a multivariate logistic regression analysis. For patients with hand soft tissue reconstruction, we carefully reviewed hospital records and identified 163 patients who met the inclusion criteria. The characteristics of these patients, flap transfer procedures and postoperative complications were recorded. Eleven predictors were identified. The correlations between pedicled flap necrosis and risk factors were analysed using a logistic regression model. Of 163 skin flaps, 125 flaps survived completely without any complications. The pedicled flap necrosis rate in hands was 11.04%, which included partial flap necrosis (7.36%) and total flap necrosis (3.68%). Soft tissue defects in fingers were noted in 68.10% of all cases. The logistic regression analysis indicated that the soft tissue defect site (P = 0.046, odds ratio (OR) = 0.079, confidence interval (CI) (0.006, 0.959)), flap size (P = 0.020, OR = 1.024, CI (1.004, 1.045)) and postoperative wound infection (P < 0.001, OR = 17.407, CI (3.821, 79.303)) were statistically significant risk factors for pedicled flap necrosis of the hand. Soft tissue defect site, flap size and postoperative wound infection were risk factors associated with pedicled flap necrosis in hand soft tissue defect reconstruction. © 2017 Royal Australasian College of Surgeons.

  6. Thermal properties of defective fullerene

    Science.gov (United States)

    Li, Jian; Zheng, Dong-Qin; Zhong, Wei-Rong

    2016-09-01

    We have investigated the thermal conductivity of defective fullerene (C60) by using the nonequilibrium molecular dynamics (MD) method. It is found that the thermal conductivity of C60 with one defect is lower than the thermal conductivity of perfect C60. However, double defects in C60 have either positive or negative influence on the thermal conductivity, which depends on the positions of the defects. The phonon spectra of perfect and defective C60 are also provided to give corresponding supports. Our results can be extended to long C60 chains, which is helpful for the thermal management of C60.

  7. Cell and Tissue Engineering

    CERN Document Server

    2012-01-01

    “Cell and Tissue Engineering” introduces the principles and new approaches in cell and tissue engineering. It includes both the fundamentals and the current trends in cell and tissue engineering, in a way useful both to a novice and an expert in the field. The book is composed of 13 chapters all of which are written by the leading experts. It is organized to gradually assemble an insight in cell and tissue function starting form a molecular nano-level, extending to a cellular micro-level and finishing at the tissue macro-level. In specific, biological, physiological, biophysical, biochemical, medical, and engineering aspects are covered from the standpoint of the development of functional substitutes of biological tissues for potential clinical use. Topics in the area of cell engineering include cell membrane biophysics, structure and function of the cytoskeleton, cell-extracellular matrix interactions, and mechanotransduction. In the area of tissue engineering the focus is on the in vitro cultivation of ...

  8. Analysis of the defect clusters in congruent lithium tantalate

    Science.gov (United States)

    Vyalikh, Anastasia; Zschornak, Matthias; Köhler, Thomas; Nentwich, Melanie; Weigel, Tina; Hanzig, Juliane; Zaripov, Ruslan; Vavilova, Evgenia; Gemming, Sibylle; Brendler, Erica; Meyer, Dirk C.

    2018-01-01

    A wide range of technological applications of lithium tantalate (LT) is closely related to the defect chemistry. In literature, several intrinsic defect models have been proposed. Here, using a combinational approach based on DFT and solid-state NMR, we demonstrate that distribution of electric field gradients (EFGs) can be employed as a fingerprint of a specific defect configuration. Analyzing the distribution of 7Li EFGs, the FT-IR and electron spin resonance (ESR) spectra, and the 7Li spin-lattice relaxation behavior, we have found that the congruent LT samples provided by two manufacturers show rather different defect concentrations and distributions although both were grown by the Czochralski method. After thermal treatment hydrogen out-diffusion and homogeneous distribution of other defects have been observed by ESR, NMR, and FT-IR. The defect structure in one of two congruent LT crystals after annealing has been identified and proved by defect formation energy considerations, whereas the more complex defect configuration, including the presence of extrinsic defects, has been suggested for the other LT sample. The approach of searching the EFG fingerprints from DFT calculations in NMR spectra can be applied for identifying the defect clusters in other complex oxides.

  9. Defect reaction network in Si-doped InAs. Numerical predictions.

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-05-01

    This Report characterizes the defects in the def ect reaction network in silicon - doped, n - type InAs predicted with first principles density functional theory. The reaction network is deduced by following exothermic defect reactions starting with the initially mobile interstitial defects reacting with common displacement damage defects in Si - doped InAs , until culminating in immobile reaction p roducts. The defect reactions and reaction energies are tabulated, along with the properties of all the silicon - related defects in the reaction network. This Report serves to extend the results for the properties of intrinsic defects in bulk InAs as colla ted in SAND 2013 - 2477 : Simple intrinsic defects in InAs : Numerical predictions to include Si - containing simple defects likely to be present in a radiation - induced defect reaction sequence . This page intentionally left blank

  10. Fermi-level pinning through defects at GaAs/oxide interfaces: A density functional study

    Science.gov (United States)

    Colleoni, Davide; Miceli, Giacomo; Pasquarello, Alfredo

    2015-09-01

    Using density functional calculations, we study a set of candidate defects for Fermi-level pinning at GaAs/oxide interfaces. The set of considered defects comprises both bulklike and interfacial defects, including As antisites, Ga and As dangling bonds, the As-As dimer/dangling bond defect, and several defect complexes. The defects are generated within atomistic model structures representing the GaAs /Al2O3 interface. Formation energies of bulklike defects are obtained and compared with those of corresponding bulk defects, while interfacial defects are studied through their relative defect energies. Finite-size corrections to the defect energies are applied through a scheme that accounts for the interfacial geometry of our models. Defect levels are defined as thermodynamic transition levels between different charge states and are calculated for all considered defects. Through an alignment procedure based on hybrid functional calculations, the defect levels are then positioned within the calculated band gap of GaAs that reproduces the experimental one, thereby enabling direct comparisons with the experimental density of defect states. Our study shows that several As-related defects show a similar amphoteric bistability between an As-As dimer state and a configuration with two doubly occupied As dangling bonds. The associated charge transition levels generally lie in the midgap region, in accord with experimental observations. This mechanism is proposed as the origin of the observed Fermi-level pinning at GaAs/oxide interfaces.

  11. Point defects in nickel

    International Nuclear Information System (INIS)

    Peretto, P.

    1969-01-01

    The defects in electron irradiated nickel (20 deg. K) or neutron irradiated nickel (28 deg. K) are studied by simultaneous analysis using the magnetic after-effect, electron microscopy and electrical resistivity recovery. We use zone refined nickel (99.999 per cent) which, for some experiments, is alloyed with a small amount of iron (for example 0.1 per cent Fe). The temperature dependant electrical recovery may be divided in four stages. The sub-stages I B (31 deg. K), I C (42 deg. K), I D (from to 57 deg. K) and I E (62 deg. K) of stage I are due to the disappearance of single interstitials into vacancies. The interstitial defect has a split configuration with a migration energy of about 0.15 eV. In the close pair which disappears in stage I B the interstitial is found to be in a 3. neighbour position whilst in stage I D it is near the direction from the vacancy. In stage I E there is no longer any interaction between the interstitial and the vacancy. The stage II is due to more complicated interstitial defects: di-interstitials for stage II B (84 deg. K) and larger and larger interstitial loops for the following sub-stages. The loops may be seen by electron microscopy. Impurities can play the role of nucleation centers for the loops. Stages III A (370 deg. K) and III B (376 deg. K) are due to two types of di-vacancies. During stage IV (410 deg. K) the single vacancies migrate. Vacancy type loops and interstitial type loops grow concurrently and disappear at about 800 deg. K as observed by electron microscopy. (author) [fr

  12. Platelet-rich plasma plus bioactive glass in the treatment of intra-bony defects: a study in dogs

    Directory of Open Access Journals (Sweden)

    Marcelo Diniz Carvalho

    2011-02-01

    Full Text Available OBJECTIVE: This study was designed to evaluate, histomorphometrically, the association of platelet-rich plasma (PRP and bioactive glass (BG in the treatment of periodontal intrabony defects. MATERIAL AND METHODS: Nine mongrel dogs were included in the study. Three-wall intrabony defects were surgically created at the mesial and distal aspect of first mandibular molar and exposed to plaque accumulation for 1 month. The defects were randomly assigned to the groups: control, BG, PRP, PRP+BG. Dogs were sacrificed 90 days after the surgeries. The histometric parameters evaluated were: length of sulcular and junctional epithelium, connective tissue adaptation, new cementum, new bone, defect extension and area of new bone filling the defect. RESULTS: A superior area of new bone was observed in PRP+BG and BG (13.80±2.32 mm² and 15.63±2.64 mm², respectively when compared to the other groups (8.19±1.46 mm² and 8.81±1.47 mm² for control and PRP, respectively. No statistically significant differences were observed in the remaining parameters. CONCLUSIONS: Within the limits of this study, it may be concluded that PRP failed to provide statistically significant improvements in the histometric parameters.

  13. Computer programs for eddy-current defect studies

    Energy Technology Data Exchange (ETDEWEB)

    Pate, J. R.; Dodd, C. V. [Oak Ridge National Lab., TN (USA)

    1990-06-01

    Several computer programs to aid in the design of eddy-current tests and probes have been written. The programs, written in Fortran, deal in various ways with the response to defects exhibited by four types of probes: the pancake probe, the reflection probe, the circumferential boreside probe, and the circumferential encircling probe. Programs are included which calculate the impedance or voltage change in a coil due to a defect, which calculate and plot the defect sensitivity factor of a coil, and which invert calculated or experimental readings to obtain the size of a defect. The theory upon which the programs are based is the Burrows point defect theory, and thus the calculations of the programs will be more accurate for small defects. 6 refs., 21 figs.

  14. Conductivity of epitaxial and CVD graphene with correlated line defects

    DEFF Research Database (Denmark)

    Radchenko, T. M.; Shylau, Artsem; Zozoulenko, I. V.

    2014-01-01

    -type scattering potential. The dc conductivity is calculated numerically for different cases of distribution of line defects. This includes a random (uncorrelated) and a correlated distribution with a prevailing direction in the orientation of lines. The anisotropy of the conductivity along and across the line...... defects is revealed, which agrees with experimental measurements for epitaxial graphene grown on SiC. We performed a detailed study of the conductivity for different defect correlations, introducing the correlation angle αmax-the maximum possible angle between any two lines. We find that for a given...... electron density, the relative enhancement of the conductivity for the case of fully correlated line defects in comparison to the case of uncorrelatecl ones is larger for a higher defect density. Finally, we, for the first time, study the conductivity of realistic samples where both extended line defects...

  15. Clinical management of soft tissue sarcomas

    International Nuclear Information System (INIS)

    Pinedo, H.M.; Verweij, J.

    1986-01-01

    This book is concerned with the clinical management of soft tissue sarcomas. Topics covered include: Radiotherapy; Pathology of soft tissue sarcomas; Surgical treatment of soft tissue sarcomas; and Chemotherapy in advanced soft tissue sarcomas

  16. Single ventricle cardiac defect

    International Nuclear Information System (INIS)

    Eren, B.; Turkmen, N.; Fedakar, R.; Cetin, V.

    2010-01-01

    Single ventricle heart is defined as a rare cardiac abnormality with a single ventricle chamber involving diverse functional and physiological defects. Our case is of a ten month-old baby boy who died shortly after admission to the hospital due to vomiting and diarrhoea. Autopsy findings revealed cyanosis of finger nails and ears. Internal examination revealed; large heart, weighing 60 grams, single ventricle, without a septum and upper membranous part. Single ventricle is a rare pathology, hence, this paper aims to discuss this case from a medico-legal point of view. (author)

  17. Osteochondral defects in the ankle: why painful?

    NARCIS (Netherlands)

    van Dijk, C. Niek; Reilingh, Mikel L.; Zengerink, Maartje; van Bergen, Christiaan J. A.

    2010-01-01

    Osteochondral defects of the ankle can either heal and remain asymptomatic or progress to deep ankle pain on weight bearing and formation of subchondral bone cysts. The development of a symptomatic OD depends on various factors, including the damage and insufficient repair of the subchondral bone

  18. Multiple congenital defects in a newborn foal

    Directory of Open Access Journals (Sweden)

    J.F. Silva

    2014-12-01

    Full Text Available A case of multiple congenital defects in a newborn foal is reported. The animal showed hypoplasia of the left pelvic limb bones, uterus unicornis, congenital diaphragmatic hernia, and unilateral renal and ureteral agenesis. This report includes the macroscopic and microscopic lesions observed in the case.

  19. Defects and diffusion in semiconductors XIV

    CERN Document Server

    Fisher, David J

    2012-01-01

    This 14th volume in the series covers the latest results in the field of Defects and Diffusion in Semiconductor. The issue also includes some original papers: An Experimental Study of the Thermal Properties of Modified 9Cr-1Mo Steel; Physico-Mechanical Properties of Sintered Iron-Silica Sand Nanoparticle Composites: A Preliminary Study; Defect and Dislocation Density Parameters of 5251 Al Alloy Using Positron Annihilation Lifetime Technique; A Novel Computational Strategy to Enhance the Ability of Elaborate Search by Entire Swarm to Find the Best Solution in Optimization of AMCs; Synthesis and

  20. Experimental reconstruction of cervical esophageal defect with artificial esophagus made of polyurethane in a dog model.

    Science.gov (United States)

    Jiang, H; Cui, Y; Ma, K; Gong, M; Chang, D; Wang, T

    2016-01-01

    artificial esophagus staying in situ after migration was not covered by epithelium, and the granulation tissue was infiltrated by a great deal of inflammatory cells. Antibodies against cytokeratin were positively expressed in epithelium of neo-esophagus. Up to 12 months after operation, antibodies against smooth muscle actin and desmin were both negatively expressed in neo-esophagus. The artificial esophagus made of non-degradable polyurethane reconstructing cervical esophageal defect is practicable. Although there are some problems, including anastomotic leakage, migration, and dysphagia, they are not lethal following good supportive therapy. The esophageal epithelium can regenerate with the supporting role of artificial esophagus. In the future, deformable artificial esophagus should be improved, and a much longer follow-up will be performed to evaluate whether the esophageal gland and skeletal muscle can regenerate. © 2014 International Society for Diseases of the Esophagus.

  1. Tissue Engineering Strategies in Ligament Regeneration

    Directory of Open Access Journals (Sweden)

    Caglar Yilgor

    2012-01-01

    Full Text Available Ligaments are dense fibrous connective tissues that connect bones to other bones and their injuries are frequently encountered in the clinic. The current clinical approaches in ligament repair and regeneration are limited to autografts, as the gold standard, and allografts. Both of these techniques have their own drawbacks that limit the success in clinical setting; therefore, new strategies are being developed in order to be able to solve the current problems of ligament grafting. Tissue engineering is a novel promising technique that aims to solve these problems, by producing viable artificial ligament substitutes in the laboratory conditions with the potential of transplantation to the patients with a high success rate. Direct cell and/or growth factor injection to the defect site is another current approach aiming to enhance the repair process of the native tissue. This review summarizes the current approaches in ligament tissue engineering strategies including the use of scaffolds, their modification techniques, as well as the use of bioreactors to achieve enhanced regeneration rates, while also discussing the advances in growth factor and cell therapy applications towards obtaining enhanced ligament regeneration.

  2. Atrioventricular septal defects among infants in Europe

    DEFF Research Database (Denmark)

    Christensen, Nikolas; Andersen, Helle; Garne, Ester

    2013-01-01

    OBJECTIVE: To describe the epidemiology of chromosomal and non-chromosomal cases of atrioventricular septal defects in Europe. METHODS: Data were obtained from EUROCAT, a European network of population-based registries collecting data on congenital anomalies. Data from 13 registries for the period...... 2000-2008 were included. RESULTS: There was a total of 993 cases of atrioventricular septal defects, with a total prevalence of 5.3 per 10,000 births (95% confidence interval 4.1 to 6.5). Of the total cases, 250 were isolated cardiac lesions, 583 were chromosomal cases, 79 had multiple anomalies, 58...... of pregnancy owing to foetal anomaly. Among the groups, additional associated cardiac anomalies were most frequent in heterotaxia cases (38%) and least frequent in chromosomal cases (8%). Coarctation of the aorta was the most common associated cardiac defect. The 1-week survival rate for live births was 94...

  3. The management of bone defects of the forearm after trauma.

    Science.gov (United States)

    Stevanovic, M; Gutow, A P; Sharpe, F

    1999-05-01

    In summary, the authors believe that traumatic bone defects of the diaphyseal forearm, fewer than 6 cm in length, can be well managed with corticocancellous bone grafting, provided the patient has an adequate soft-tissue envelope. In cases of soft-tissue compromise, primary bone grafting is still the treatment of choice, combined with simultaneous soft-tissue coverage. This does not exclude the use of immediate primary shortening. Traumatic bone defects larger than 6 cm can best be managed with osteoseptocutaneous free fibular graft with excellent functional and cosmetic results. The creation of a one-bone forearm is rarely necessary, but remains a treatment option for an otherwise unsalvageable extremity. Osteo-articular defects can be more difficult to manage. Proximal osteo-articular defects of the radial head can be treated with excision or placement of a titanium radial head prosthesis. Distal osteo-articular defects may be better addressed in the case of radial bone loss by primary wrist fusion and, in the ulna, by a primary Darrach or Suave-Kapandji procedure.

  4. Tissue bank: Sri Lanka

    International Nuclear Information System (INIS)

    2003-01-01

    Human degenerative diseases and congenital defects are common throughout the world. Many people suffer also from burns, fractures and nerve damage resulting from traumatic accidents and outbreaks of violence which occur all too frequently, especially in poorer countries. Far too many people are impaired for life because they have no access to treatment or simply cannot afford it. The Department of Technical Co-operation is sponsoring a programme, with technical support from the Division of Nuclear Medicine, to improve facilities at the Sri Lanka Tissue Bank. (IAEA)

  5. Dipole defects in beryl

    International Nuclear Information System (INIS)

    Holanda, B A; Cordeiro, R C; Blak, A R

    2010-01-01

    Dipole defects in gamma irradiated and thermally treated beryl (Be 3 Al 2 Si 6 O 18 ) samples have been studied using the Thermally Stimulated Depolarization Currents (TSDC) technique. TSDC experiments were performed in pink (morganite), green (emerald), blue (aquamarine) and colourless (goshenite) natural beryl. TSDC spectra present dipole peaks at 190K, 220K, 280K and 310K that change after gamma irradiation and thermal treatments. In morganite samples, for thermal treatments between 700K and 1100K, the 280K peak increase in intensity and the band at 220K disappears. An increase of the 280K peak and a decrease of the 190K peak were observed in the TSDC spectra of morganite after a gamma irradiation of 25kGy performed after the thermal treatments. In the case of emerald samples, thermal treatments enhanced the 280K peak and gamma irradiation partially destroyed this band. The goshenite TSDC spectra present only one band at 280K that is not affected either by thermal treatments or by gamma irradiation. All the observed peaks are of dipolar origin because the intensity of the bands is linearly dependent on the polarization field, behaviour of dipole defects. The systematic study, by means of TSDC measurements, of ionizing irradiation effects and thermal treatments in these crystals makes possible a better understanding of the role played by the impurities in beryl crystals.

  6. Severe cardiac defect in a patient with the OEIS complex.

    Science.gov (United States)

    Kant, S G; Bartelings, M M; Kibbelaar, R E; Van Haeringen, A

    1997-10-01

    The OEIS complex is an association of fetal malformations including omphalocele, exstrophy of the cloaca, imperforate anus and spinal defects. We present a fetus with the OEIS complex in combination with a cardiac defect. Until now very few cases with this combination have been described.

  7. Tissue-engineered autologous grafts for facial bone reconstruction.

    Science.gov (United States)

    Bhumiratana, Sarindr; Bernhard, Jonathan C; Alfi, David M; Yeager, Keith; Eton, Ryan E; Bova, Jonathan; Shah, Forum; Gimble, Jeffrey M; Lopez, Mandi J; Eisig, Sidney B; Vunjak-Novakovic, Gordana

    2016-06-15

    Facial deformities require precise reconstruction of the appearance and function of the original tissue. The current standard of care-the use of bone harvested from another region in the body-has major limitations, including pain and comorbidities associated with surgery. We have engineered one of the most geometrically complex facial bones by using autologous stromal/stem cells, native bovine bone matrix, and a perfusion bioreactor for the growth and transport of living grafts, without bone morphogenetic proteins. The ramus-condyle unit, the most eminent load-bearing bone in the skull, was reconstructed using an image-guided personalized approach in skeletally mature Yucatán minipigs (human-scale preclinical model). We used clinically approved decellularized bovine trabecular bone as a scaffolding material and crafted it into an anatomically correct shape using image-guided micromilling to fit the defect. Autologous adipose-derived stromal/stem cells were seeded into the scaffold and cultured in perfusion for 3 weeks in a specialized bioreactor to form immature bone tissue. Six months after implantation, the engineered grafts maintained their anatomical structure, integrated with native tissues, and generated greater volume of new bone and greater vascular infiltration than either nonseeded anatomical scaffolds or untreated defects. This translational study demonstrates feasibility of facial bone reconstruction using autologous, anatomically shaped, living grafts formed in vitro, and presents a platform for personalized bone tissue engineering. Copyright © 2016, American Association for the Advancement of Science.

  8. Periodontal tissue engineering strategies based on nonoral stem cells.

    Science.gov (United States)

    Requicha, João Filipe; Viegas, Carlos Alberto; Muñoz, Fernando; Reis, Rui Luís; Gomes, Manuela Estima

    2014-01-01

    Periodontal disease is an inflammatory disease which constitutes an important health problem in humans due to its enormous prevalence and life threatening implications on systemic health. Routine standard periodontal treatments include gingival flaps, root planning, application of growth/differentiation factors or filler materials and guided tissue regeneration. However, these treatments have come short on achieving regeneration ad integrum of the periodontium, mainly due to the presence of tissues from different embryonic origins and their complex interactions along the regenerative process. Tissue engineering (TE) aims to regenerate damaged tissue by providing the repair site with a suitable scaffold seeded with sufficient undifferentiated cells and, thus, constitutes a valuable alternative to current therapies for the treatment of periodontal defects. Stem cells from oral and dental origin are known to have potential to regenerate these tissues. Nevertheless, harvesting cells from these sites implies a significant local tissue morbidity and low cell yield, as compared to other anatomical sources of adult multipotent stem cells. This manuscript reviews studies describing the use of non-oral stem cells in tissue engineering strategies, highlighting the importance and potential of these alternative stem cells sources in the development of advanced therapies for periodontal regeneration. Copyright © 2013 Wiley Periodicals, Inc.

  9. Prevalence and prognostic role of mismatch repair gene defect in endometrial cancer patients.

    Science.gov (United States)

    Tangjitgamol, Siriwan; Kittisiam, Thannaporn; Tanvanich, Sujitra

    2017-09-01

    The study was to evaluate the prevalence of mismatch repair gene defect among Thai patients with endometrial cancer and its association with clinico-pathological features and survivals. The formalin fixed paraffin-embedded blocks of EMC tissue from hysterectomy specimens of patients having surgery in our institution between 1 Jan 1995 and 31 December 2016 were assessed for the immunohistochemical expression of 4 mismatch repair proteins (MLH1, PMS, MSH2, MSH 6). Mismatch repair gene defect was determined by a negative expression of at least 1 protein. Among 385 EMC patients included in the study, mean age was 57.3 ± 10.8 years with 62.3% aged ⩽ 60 years. The most frequent mismatch repair gene defect was MSH6 (38.7%), followed by PMS2 (34.3%), MLH1 (33.2%), and MSH2 (16.4%). Overall, 55.1% showed negative expression of at least one protein. We found significantly higher mismatch repair gene defect in patients aged ⩽ 60 years, with early stage disease, and negative lymph node status than the other comparative groups: 59.2% vs 48.3% for age (p = 0.037), 58.2% vs 45.2% (p = 0.027) for stage, and 58.1% vs 44.6% (p = 0.048) for nodal status. The 5-year progression-free survival, overall survival, and endometrial cancer-specific survival of patients with mismatch repair gene defect was higher than those without gene defect. The differences were statistically significant for only progression-free survival and endometrial cancer-specific survival: 87.7% (95% confidence interval = 83.0%-92.4%) vs 81.5% (95% confidence interval = 75.4%-87.6%) (p = 0.049) for progression-free survival and 91.0% (95% confidence interval = 86.9%-95.1%) vs 85.5% (95% confidence interval = 80.0%-91.0%) (p = 0.044) for endometrial cancer-specific survival, respectively. In conclusion, more than half of Thai endometrial cancer patients had mismatch repair gene defect. The patients with mismatch repair gene defect had significantly younger age (⩽ 60 years) and better prognosis in terms of

  10. Lateral pedicle graft for repair of residual gingival defect following complete surgical excision of a pyogenic granuloma

    OpenAIRE

    Awadhesh Kumar Singh; Abhisek Gautam

    2016-01-01

    The pyogenic granuloma, one of the gingival lesions, has recurrence rate of 16%. To minimize the recurrence rate, it must be completely excised. Complete surgical excision can result in residual gingival defect. McCrea repaired residual gingival defect by subepithelial connective tissue graft with lateral mucogingival pedicle flap, and Choudhary et al. managed residual gingival defect by subepithelial connective tissue graft only. The aim of this case report was to use lateral pedicle graft f...

  11. [Biological downsizing : Acetabular defect reconstruction in revision total hip arthroplasty].

    Science.gov (United States)

    Koob, S; Scheidt, S; Randau, T M; Gathen, M; Wimmer, M D; Wirtz, D C; Gravius, S

    2017-02-01

    Periacetabular bony defects remain a great challenge in revision total hip arthroplasty. After assessment and classification of the defect and selection of a suitable implant the primary stable fixation and sufficient biological reconstitution of a sustainable bone stock are essential for long term success in acetabular revision surgery. Biological defect reconstruction aims for the down-sizing of periacetabular defects for later revision surgeries. In the field of biological augmentation several methods are currently available. Autologous transplants feature a profound osseointegrative capacity. However, limitations such as volume restrictions and secondary complications at the donor site have to be considered. Structural allografts show little weight bearing potential in the long term and high failure rates. In clinical practice, the usage of spongious chips implanted via impaction bone grafting technique in combination with antiprotrusio cages for the management of contained defects have shown promising long time results. Nevertheless, when dealing with craniolateral acetabular and dorsal column defects, the additional implantation of macroporous metal implants or augments should be considered since biological augmentation has shown little clinical success in these particular cases. This article provides an overview of the current clinically available biological augmentation methods of peri-acetabular defects. Due to the limitations of autologous and allogeneic bone transplants in terms of size and availability, the emerging field of innovative implantable tissue engineering constructs gains interest and will also be discussed in this article.

  12. Efficacy of Honeycomb TCP-induced Microenvironment on Bone Tissue Regeneration in Craniofacial Area.

    Science.gov (United States)

    Watanabe, Satoko; Takabatake, Kiyofumi; Tsujigiwa, Hidetsugu; Watanabe, Toshiyuki; Tokuyama, Eijiro; Ito, Satoshi; Nagatsuka, Hitoshi; Kimata, Yoshihiro

    2016-01-01

    Artificial bone materials that exhibit high biocompatibility have been developed and are being widely used for bone tissue regeneration. However, there are no biomaterials that are minimally invasive and safe. In a previous study, we succeeded in developing honeycomb β-tricalcium phosphate (β-TCP) which has through-and-through holes and is able to mimic the bone microenvironment for bone tissue regeneration. In the present study, we investigated how the difference in hole-diameter of honeycomb β-TCP (hole-diameter: 75, 300, 500, and 1600 μm) influences bone tissue regeneration histologically. Its osteoconductivity was also evaluated by implantation into zygomatic bone defects in rats. The results showed that the maximum bone formation was observed on the β-TCP with hole-diameter 300μm, included bone marrow-like tissue and the pattern of bone tissue formation similar to host bone. Therefore, the results indicated that we could control bone tissue formation by creating a bone microenvironment provided by β-TCP. Also, in zygomatic bone defect model with honeycomb β-TCP, the result showed there was osseous union and the continuity was reproduced between the both edges of resected bone and β-TCP, which indicated the zygomatic bone reproduction fully succeeded. It is thus thought that honeycomb β-TCP may serve as an excellent biomaterial for bone tissue regeneration in the head, neck and face regions, expected in clinical applications.

  13. In situ repair of bone and cartilage defects using 3D scanning and 3D printing

    OpenAIRE

    Li, Lan; Yu, Fei; Shi, Jianping; Shen, Sheng; Teng, Huajian; Yang, Jiquan; Wang, Xingsong; Jiang, Qing

    2017-01-01

    Three-dimensional (3D) printing is a rapidly emerging technology that promises to transform tissue engineering into a commercially successful biomedical industry. However, the use of robotic bioprinters alone is not sufficient for disease treatment. This study aimed to report the combined application of 3D scanning and 3D printing for treating bone and cartilage defects. Three different kinds of defect models were created to mimic three orthopedic diseases: large segmental defects of long bon...

  14. Cloacal Exstrophy : An Epidemiologic Study From the International Clearinghouse for Birth Defects Surveillance and Research

    NARCIS (Netherlands)

    Feldkamp, Marcia L.; Botto, Lorenzo D.; Amar, Emmanuelle; Bakker, Marian K.; Bermejo-Sanchez, Eva; Bianca, Sebastiano; Canfield, Mark A.; Castilla, Eduardo E.; Clementi, Maurizio; Csaky-Szunyogh, Melinda; Leoncini, Emanuele; Li, Zhu; Lowry, R. Brian; Mastroiacovo, Pierpaolo; Merlob, Paul; Morgan, Margery; Mutchinick, Osvaldo M.; Rissmann, Anke; Ritvanen, Annukka; Siffel, Csaba; Carey, John C.

    2011-01-01

    Cloacal exstrophy presents as a complex abdominal wall defect thought to result from a mesodermal abnormality. Anatomically, its main components are Omphalocele, bladder Exstrophy and Imperforate anus. Other associated malformations include renal malformations and Spine defects (OEIS complex).

  15. Autosomal dominant familial radial luxation, carpal fusion and scapular dysplasia with variable heart defects

    NARCIS (Netherlands)

    van Bever, Y.; Dijkstra, P. F.; Hennekam, R. C.

    1996-01-01

    A family is described with skeletal abnormalities involving the shoulder, elbow, and hand, in combination with variable cardiac defects including conduction defects and anatomical anomalies. The disorder followed an autosomal dominant pattern of inheritance with apparently full penetrance for the

  16. Intermittent′ restrictive ventricular septal defect in Tetralogy of Fallot

    Directory of Open Access Journals (Sweden)

    Sudhir S Shetkar

    2015-01-01

    Full Text Available Ventricular septal defect (VSD in Tetralogy of Fallot (TOF is usually large and non-restrictive with equalization of right and left ventricular pressures. Restrictive VSD in TOF is rare. We present an unusual case of TOF with restriction to VSD caused by accessory tricuspid valve tissue that varied with respiration.

  17. Incomplete bone regeneration of rabbit calvarial defects using different membranes

    DEFF Research Database (Denmark)

    Aaboe, M; Pinholt, E M; Schou, S

    1998-01-01

    group. Undecalcified sections were prepared for histologic evaluation after an observation period of 8 weeks. Complete bone healing of the defects was not observed in any of the specimens. The Polyglactin 910 material lacks physical strength, resulting in collapse of the membrane and brain tissue...

  18. Maternal occupation and the risk of birth defects: an overview from the National Birth Defects Prevention Study.

    NARCIS (Netherlands)

    Herdt-Losavio, M.L.; Lin, S.; Chapman, B.R.; Hooiveld, M.; Olshan, A.; Liu, X.; DePersis, R.D.; Zhu, J.; Druschel, C.M.

    2010-01-01

    OBJECTIVES: To examine the association between a spectrum of 24 maternal occupations and 45 birth defects for hypothesis generating purposes. METHODS: Cases of isolated and multiple birth defects (n = 8977) and all non-malformed live-born control births (n = 3833) included in the National Birth

  19. [Strategies to choose scaffold materials for tissue engineering].

    Science.gov (United States)

    Gao, Qingdong; Zhu, Xulong; Xiang, Junxi; Lü, Yi; Li, Jianhui

    2016-02-01

    Current therapies of organ failure or a wide range of tissue defect are often not ideal. Transplantation is the only effective way for long time survival. But it is hard to meet huge patients demands because of donor shortage, immune rejection and other problems. Tissue engineering could be a potential option. Choosing a suitable scaffold material is an essential part of it. According to different sources, tissue engineering scaffold materials could be divided into three types which are natural and its modified materials, artificial and composite ones. The purpose of tissue engineering scaffold is to repair the tissues or organs damage, so could reach the ideal recovery in its function and structure aspect. Therefore, tissue engineering scaffold should even be as close as much to the original tissue or organs in function and structure. We call it "organic scaffold" and this strategy might be the drastic perfect substitute for the tissues or organs in concern. Optimized organization with each kind scaffold materials could make up for biomimetic structure and function of the tissue or organs. Scaffold material surface modification, optimized preparation procedure and cytosine sustained-release microsphere addition should be considered together. This strategy is expected to open new perspectives for tissue engineering. Multidisciplinary approach including material science, molecular biology, and engineering might find the most ideal tissue engineering scaffold. Using the strategy of drawing on each other strength and optimized organization with each kind scaffold material to prepare a multifunctional biomimetic tissue engineering scaffold might be a good method for choosing tissue engineering scaffold materials. Our research group had differentiated bone marrow mesenchymal stem cells into bile canaliculi like cells. We prepared poly(L-lactic acid)/poly(ε-caprolactone) biliary stent. The scaffold's internal played a part in the long-term release of cytokines which

  20. Topological defects in extended inflation

    International Nuclear Information System (INIS)

    Copeland, E.J.; Kolb, E.W.; Chicago Univ., IL; Liddle, A.R.

    1990-04-01

    We consider the production of topological defects, especially cosmic strings, in extended inflation models. In extended inflation, the Universe passes through a first-order phase transition via bubble percolation, which naturally allows defects to form at the end of inflation. The correlation length, which determines the number density of the defects, is related to the mean size of bubbles when they collide. This mechanism allows a natural combination of inflation and large-scale structure via cosmic strings. 18 refs

  1. Diaphragmatic defect in trisomy 13

    International Nuclear Information System (INIS)

    Reinbold, W.D.; Reinwein, H.; Back, E.

    1986-01-01

    Congenital diaphragmatic defect is often combined with other malformations that are severe or fatal. The rare finding of a congenital diaphragmatic defect in a newborn with trisomy 13 is reported. The newborn died within 2 days. Postmortem examination showed typical malformations due to trisomy 13 besides a diaphragmatic defect of left retrosternal position. Karyotype revealed a 13/14 translocation of trisomy 13. (orig.) [de

  2. Topological defects in extended inflation

    International Nuclear Information System (INIS)

    Copeland, E.J.; Kolb, E.W.; Liddle, A.R.

    1990-01-01

    We consider the production of topological defects, especially cosmic strings, in extended-inflation models. In extended inflation, the Universe passes through a first-order phase transition via bubble percolation, which naturally allows defects to form at the end of inflation. The correlation length, which determines the number density of the defects, is related to the mean size of the bubbles when they collide. This mechanism allows a natural combination of inflation and large-scale structure via cosmic strings

  3. 3D Volumetric Modeling and Microvascular Reconstruction of Irradiated Lumbosacral Defects after Oncologic Resection.

    Science.gov (United States)

    Garcia-Tutor, Emilio; Romeo, Marco; Chae, Michael P; Hunter-Smith, David J; Rozen, Warren Matthew

    2016-01-01

    Locoregional flaps are sufficient in most sacral reconstructions. However, large sacral defects due to malignancy necessitate a different reconstructive approach, with local flaps compromised by radiation and regional flaps inadequate for broad surface areas or substantial volume obliteration. In this report, we present our experience using free muscle transfer for volumetric reconstruction, in such cases, and demonstrate three-dimensional (3D) haptic models of the sacral defect to aid preoperative planning. Five consecutive patients with irradiated sacral defects secondary to oncologic resections were included, surface area ranging from 143-600 cm 2 . Latissimus dorsi (LD)-based free flap sacral reconstruction was performed in each case, between 2005 and 2011. Where the superior gluteal artery was compromised, the subcostal artery (SA) was used as a recipient vessel. Microvascular technique, complications, and outcomes are reported. The use of volumetric analysis and 3D printing is also demonstrated, with imaging data converted to 3D images suitable for 3D printing with Osirix software (Pixmeo, Geneva, Switzerland). An office-based, desktop 3D printer was used to print 3D models of sacral defects, used to demonstrate surface area and contour and produce a volumetric print of the dead space needed for flap obliteration. The clinical series of LD free flap reconstructions is presented, with successful transfer in all cases, and adequate soft-tissue cover and volume obliteration achieved. The original use of the SA as a recipient vessel was successfully achieved. All wounds healed uneventfully. 3D printing is also demonstrated as a useful tool for 3D evaluation of volume and dead space. Free flaps offer unique benefits in sacral reconstruction where local tissue is compromised by irradiation and tumor recurrence, and dead space requires accurate volumetric reconstruction. We describe for the first time the use of the SA as a recipient in free flap sacral

  4. Point defects in lines in single crystalline phosphorene: directional migration and tunable band gaps.

    Science.gov (United States)

    Li, Xiuling; Ma, Liang; Wang, Dayong; Zeng, Xiao Cheng; Wu, Xiaojun; Yang, Jinlong

    2016-10-20

    Extended line defects in two-dimensional (2D) materials can play an important role in modulating their electronic properties. During the experimental synthesis of 2D materials, line defects are commonly generated at grain boundaries between domains of different orientations. In this work, twelve types of line-defect structures in single crystalline phosphorene are examined by using first-principles calculations. These line defects are typically formed via migration and aggregation of intrinsic point defects, including the Stone-Wales (SW), single or double vacancy (SV or DV) defects. Our calculated results demonstrate that the migration of point defects in phosphorene is anisotropic, for instance, the lowest migration energy barriers are 1.39 (or 0.40) and 2.58 (or 0.49) eV for SW (or SV) defects in zigzag and armchair directions, respectively. The aggregation of point defects into lines is energetically favorable compared with the separated point defects in phosphorene. In particular, the axis of line defects in phosphorene is direction-selective, depending on the composed point defects. The presence of line defects effectively modulates the electronic properties of phosphorene, rendering the defect-containing phosphorene either metallic or semiconducting with a tunable band gap. Of particular interest is the fact that the SV-based line defect can behave as a metallic wire, suggesting a possibility to fabricate a circuit with subnanometer widths in the semiconducting phosphorene for nanoscale electronic application.

  5. Strip defect recognition in electrical tests of silicon microstrip sensors

    Energy Technology Data Exchange (ETDEWEB)

    Valentan, Manfred, E-mail: valentan@mpp.mpg.de

    2017-02-11

    This contribution describes the measurement procedure and data analysis of AC-coupled double-sided silicon microstrip sensors with polysilicon resistor biasing. The most thorough test of a strip sensor is an electrical measurement of all strips of the sensor; the measured observables include e.g. the strip's current and the coupling capacitance. These measurements are performed to find defective strips, e.g. broken capacitors (pinholes) or implant shorts between two adjacent strips. When a strip has a defect, its observables will show a deviation from the “typical value”. To recognize and quantify certain defects, it is necessary to determine these typical values, i.e. the values the observables would have without the defect. As a novel approach, local least-median-of-squares linear fits are applied to determine these “would-be” values of the observables. A least-median-of-squares fit is robust against outliers, i.e. it ignores the observable values of defective strips. Knowing the typical values allows to recognize, distinguish and quantify a whole range of strip defects. This contribution explains how the various defects appear in the data and in which order the defects can be recognized. The method has been used to find strip defects on 30 double-sided trapezoidal microstrip sensors for the Belle II Silicon Vertex Detector, which have been measured at the Institute of High Energy Physics, Vienna (Austria).

  6. Who named the quantum defect?

    Energy Technology Data Exchange (ETDEWEB)

    Rau, A.R.P. [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Physics and Astronomy; Inokuti, M. [Argonne National Lab., IL (United States). Physics Div.

    1997-08-01

    The notion of the quantum defect is important in atomic and molecular spectroscopy and also in unifying spectroscopy with collision theory. In the latter context, the quantum defect may be viewed as an ancestor of the phase shift. However, the origin of the term quantum defect does not seem to be explained in standard textbooks. It occurred in a 1921 paper by Schroedinger, preceding quantum mechanics, yet giving the correct meaning as an index of the short-range interactions with the core of an atom. The authors present the early history of the quantum-defect idea, and sketch its recent developments.

  7. Biomaterials with antibacterial and osteoinductive properties to repair infected bone defects

    NARCIS (Netherlands)

    Lu, H.; Liu, Y.; Guo, J.; Wu, H.; Wang, J.; Wu, G.

    2016-01-01

    The repair of infected bone defects is still challenging in the fields of orthopedics, oral implantology and maxillofacial surgery. In these cases, the self-healing capacity of bone tissue can be significantly compromised by the large size of bone defects and the potential/active bacterial activity.

  8. Guided bone regeneration : the influence of barrier membranes on bone grafts and bone defects

    NARCIS (Netherlands)

    Gielkens, Pepijn Frans Marie

    2008-01-01

    Guided bone regeneration (GBR) can be described as the use of a barrier membrane to provide a space available for new bone formation in a bony defect. The barrier membrane protects the defect from in-growth of soft tissue cells and allows bone progenitor cells to develop bone within a blood clot

  9. Reconstruction of Complex Facial Defects Using Cervical Expanded Flap Prefabricated by Temporoparietal Fascia Flap.

    Science.gov (United States)

    Zhang, Ling; Yang, Qinghua; Jiang, Haiyue; Liu, Ge; Huang, Wanlu; Dong, Weiwei

    2015-09-01

    Reconstruction of complex facial defects using cervical expanded flap prefabricated by temporoparietal fascia flap. Complex facial defects are required to restore not only function but also aesthetic appearance, so it is vital challenge for plastic surgeons. Skin grafts and traditional flap transfer cannot meet the reconstructive requirements of color and texture with recipient. The purpose of this sturdy is to create an expanded prefabricated temporoparietal fascia flap to repair complex facial defects. Two patients suffered severe burns on the face underwent complex facial resurfacing with prefabricated cervical flap. The vasculature of prefabricated flap, including the superficial temporal vessel and surrounding fascia, was used as the vascular carrier. The temporoparietal fascia flap was sutured underneath the cervical subcutaneous tissue, and expansion was begun in postoperative 1 week. After 4 to 6 months of expansion, the expander was removed, facial scars were excised, and cervical prefabricated flap was elevated and transferred to repair the complex facial defects. Two complex facial defects were repaired successfully by prefabricated temporoparietal fascia flap, and prefabricated flaps survived completely. On account of donor site's skin was thinner and expanded too fast, 1 expanded skin flap was rupture during expansion, but necrosis was not occurred after the 2nd operation. Venous congestion was observed in 1 patient, but after dressing, flap necrosis was not happened. Donor site was closed primarily. Postoperative follow-up 6 months, the color, texture of prefabricated flap was well-matched with facial skin. This method of expanded prefabricated flap may provide a reliable solution to the complex facial resurfacing.

  10. Monti’s procedure as an alternative technique in complex urethral distraction defect

    Directory of Open Access Journals (Sweden)

    Jalil Hosseini

    2010-06-01

    Full Text Available PURPOSE: Pelvic fracture urethral distraction defect is usually managed by the end to end anastomotic urethroplasty. Surgical repair of those patients with post-traumatic complex posterior urethral defects, who have undergone failed previous surgical treatments, remains one of the most challenging problems in urology. Appendix urinary diversion could be used in such cases. However, the appendix tissue is not always usable. We report our experience on management of patients with long urethral defect with history of one or more failed urethroplasties by Monti channel urinary diversion. MATERIALS AND METHODS: From 2001 to 2007, we evaluated data from 8 male patients aged 28 to 76 years (mean age 42.5 in whom the Monti technique was performed. All cases had history of posterior urethral defect with one or more failed procedures for urethral reconstruction including urethroplasty. A 2 to 2.5 cm segment of ileum, which had a suitable blood supply, was cut. After the re-anastomosis of the ileum, we closed the opened ileum transversely surrounding a 14-16 Fr urethral catheter using running Vicryl sutures. The newly built tube was used as an appendix during diversion. RESULTS: All patients performed catheterization through the conduit without difficulty and stomal stenosis. Mild stomal incontinence occurred in one patient in the supine position who became continent after adjustment of the catheterization intervals. There was no dehiscence, necrosis or perforation of the tube. CONCLUSION: Based on our data, Monti’s procedure seems to be a valuable technique in patients with very long complicated urethral defect who cannot be managed with routine urethroplastic techniques.

  11. Studies of defects and defect agglomerates by positron annihilation spectroscopy

    DEFF Research Database (Denmark)

    Eldrup, Morten Mostgaard; Singh, B.N.

    1997-01-01

    A brief introduction to positron annihilation spectroscopy (PAS), and in particular lo its use for defect studies in metals is given. Positrons injected into a metal may become trapped in defects such as vacancies, vacancy clusters, voids, bubbles and dislocations and subsequently annihilate from...

  12. Defective membrane remodeling in neuromuscular diseases: insights from animal models.

    Directory of Open Access Journals (Sweden)

    Belinda S Cowling

    Full Text Available Proteins involved in membrane remodeling play an essential role in a plethora of cell functions including endocytosis and intracellular transport. Defects in several of them lead to human diseases. Myotubularins, amphiphysins, and dynamins are all proteins implicated in membrane trafficking and/or remodeling. Mutations in myotubularin, amphiphysin 2 (BIN1, and dynamin 2 lead to different forms of centronuclear myopathy, while mutations in myotubularin-related proteins cause Charcot-Marie-Tooth neuropathies. In addition to centronuclear myopathy, dynamin 2 is also mutated in a dominant form of Charcot-Marie-Tooth neuropathy. While several proteins from these different families are implicated in similar diseases, mutations in close homologues or in the same protein in the case of dynamin 2 lead to diseases affecting different tissues. This suggests (1 a common molecular pathway underlying these different neuromuscular diseases, and (2 tissue-specific regulation of these proteins. This review discusses the pathophysiology of the related neuromuscular diseases on the basis of animal models developed for proteins of the myotubularin, amphiphysin, and dynamin families. A better understanding of the common mechanisms between these neuromuscular disorders will lead to more specific health care and therapeutic approaches.

  13. Pump apparatus including deconsolidator

    Energy Technology Data Exchange (ETDEWEB)

    Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew

    2014-10-07

    A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.

  14. Birth defects surveillance in China.

    Science.gov (United States)

    Dai, Li; Zhu, Jun; Liang, Juan; Wang, Yan-Ping; Wang, He; Mao, Meng

    2011-11-01

    Birth defects are a global public health problem because of their large contribution to infant mortalities and disabilities. It is estimated that 4%-6% of Chinese newborns are affected by birth defects every year. Surveillance is a basic approach to understanding the occurrence and associated factors of birth defects. The Ministry of Health of China initiated a national hospital-based birth defects monitoring system 20 years ago. Nearly every province in this country has established its own surveillance system in the past. The authors reviewed the result of the monitoring system at different administrative levels in China. Available publications on the surveillance of birth defects and data from national and provincial birth defects surveillance systems were reviewed to evaluate the effectiveness of the surveillance systems. According to the 2009 data, the national hospital-based birth defects surveillance system monitored over 1.3 million births, which accounted for more than 8% of births in China. In addition, 30 provincial hospital-based surveillance programs covered a birth population of more than 3.6 million (22% of births in China). Great achievements have been made in terms of case ascertainment, data quality control, and online reporting. But the surveillance systems in China still have some limitations. A short ascertainment period may miss some internal anomalies, inherited metabolic diseases, and malformed fetus aborted before the 28th gestational week. Discrepancies in antenatal or postnatal diagnosis of birth defects between surveillance institutes may affect the detection rate and introduce biases. Absence of baseline data and lack of integrated database systems limit the application of surveillance data to etiological studies and affect the process of decision-making. The surveillance system for birth defects is prerequisite to propose, conduct and assess any interventions for the disease. To meet the need of study and prevention of birth defects

  15. Study on on-machine defects measuring system on high power laser optical elements

    Science.gov (United States)

    Luo, Chi; Shi, Feng; Lin, Zhifan; Zhang, Tong; Wang, Guilin

    2017-10-01

    The influence of surface defects on high power laser optical elements will cause some harm to the performances of imaging system, including the energy consumption and the damage of film layer. To further increase surface defects on high power laser optical element, on-machine defects measuring system was investigated. Firstly, the selection and design are completed by the working condition analysis of the on-machine defects detection system. By designing on processing algorithms to realize the classification recognition and evaluation of surface defects. The calibration experiment of the scratch was done by using the self-made standard alignment plate. Finally, the detection and evaluation of surface defects of large diameter semi-cylindrical silicon mirror are realized. The calibration results show that the size deviation is less than 4% that meet the precision requirement of the detection of the defects. Through the detection of images the on-machine defects detection system can realize the accurate identification of surface defects.

  16. Thermal buckling behavior of defective CNTs under pre-load: A molecular dynamics study.

    Science.gov (United States)

    Mehralian, Fahimeh; Tadi Beni, Yaghoub; Kiani, Yaser

    2017-05-01

    Current study is concentrated on the extraordinary properties of defective carbon nanotubes (CNTs). The role of vacancy defects in thermal buckling response of precompressed CNTs is explored via molecular dynamics (MD) simulations. Defective CNTs are initially compressed at a certain ratio of their critical buckling strain and then undergo a uniform temperature rise. Comprehensive study is implemented on both armchair and zigzag CNTs with different vacancy defects including monovacancy, symmetric bivacancy and asymmetric bivacancy. The results reveal that defects have a pronounced impact on the buckling behavior of CNTs; interestingly, defective CNTs under compressive pre-load show higher resistance to thermal buckling than pristine ones. In the following, the buckling response of defective CNTs is shown to be dependent on the vacancy defects, location of defects and chirality. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Progressive Muscle Cell Delivery as a Solution for Volumetric Muscle Defect Repair

    OpenAIRE

    Ji Hyun Kim; In Kap Ko; Anthony Atala; James J. Yoo

    2016-01-01

    Reconstructing functional volumetric tissue in vivo following implantation remains a critical challenge facing cell-based approaches. Several pre-vascularization approaches have been developed to increase cell viability following implantation. Structural and functional restoration was achieved in a preclinical rodent tissue defect; however, the approach used in this model fails to repair larger (>mm) defects as observed in a clinical setting. We propose an effective cell delivery system utili...

  18. Optical modulator including grapene

    Science.gov (United States)

    Liu, Ming; Yin, Xiaobo; Zhang, Xiang

    2016-06-07

    The present invention provides for a one or more layer graphene optical modulator. In a first exemplary embodiment the optical modulator includes an optical waveguide, a nanoscale oxide spacer adjacent to a working region of the waveguide, and a monolayer graphene sheet adjacent to the spacer. In a second exemplary embodiment, the optical modulator includes at least one pair of active media, where the pair includes an oxide spacer, a first monolayer graphene sheet adjacent to a first side of the spacer, and a second monolayer graphene sheet adjacent to a second side of the spacer, and at least one optical waveguide adjacent to the pair.

  19. Ocular Defects in Photosensitive Epilepsy

    Directory of Open Access Journals (Sweden)

    Ebere C. Anyanwu

    2004-01-01

    Full Text Available Patients with photosensitive epilepsy are susceptible to seizures due to photoparoxysmal response (PPR. This response adversely precipitates factors that modify the functional status of the visual system. Such factors may or may not be evident superficially, but may lead to ocular defects due to trauma, hormonal imbalance, abnormal intraocular pressure (IOP, or any other reflex-inducing stimuli. The extent to which photosensitive epileptic patients suffer from PPR-related ocular defects has not been documented fully. In this investigation, ocular defects in patients with photosensitive epilepsy are studied using visual-evoked response (VER. A total of 212 photosensitive epileptic patients were studied to ascertain the magnitude and distribution of ocular defects using the changes in EEG and visual-evoked potential (VEP; 51% of the patients were female, the age range was 1–46 years. The major ocular defects and complications found were visual field defects, optic nerve abnormalities, nystagmus, cataracts, amblyopia, and migraine. These findings were analyzed according to age and sex. The relationship between the ocular abnormalities and the interpretations of the changes in the characteristics of the VEP indicated that optic-related atrophies, visual defects, optic neuritis, chiasmal compression, nystagmus, migraine headache, cataracts, and amblyopia were prevalent in photosensitive epileptic patients at varying degrees. The results showed that although ocular defects in photosensitive epilepsy may not be obvious differentially, VEP can be used in their diagnosis, contrary to earlier studies reporting that VEP is not of much value in epilepsy diagnosis.

  20. Space mapping and defect correction

    NARCIS (Netherlands)

    Echeverría, D.; Hemker, P.W.

    2005-01-01

    In this paper we show that space-mapping optimization can be understood in the framework of defect correction. Then, space-mapping algorithms can be seen as special cases of defect correction iteration. In order to analyze the properties of space mapping and the space-mapping function, we introduce

  1. Birth defects surveillance·

    African Journals Online (AJOL)

    1989-07-01

    Jul 1, 1989 ... A pilot birth defects surveillance system was established in. 1982 as part of an epidemiological baseline study pertaining to potential changes in water quality in the Cape Peninsula. The methodology used for reporting birth defects for two information systems, one hospital-based and the other popu-.

  2. Treatment of infrabony defects with platelet-rich fibrin along with bone graft: Case report

    Directory of Open Access Journals (Sweden)

    Surekha Y Bhedasgaonkar

    2015-01-01

    Full Text Available Although periodontitis is an infectious disease of periodontal tissues, changes that occur in the bone are crucial, because destruction of bone is responsible for tooth loss. Although horizontal bone loss is most common, vertical bone loss is more amenable to regenerative periodontal therapy. Recently, importance has been given to use of platelet-rich fibrin (PRF for predictably obtaining periodontal regeneration. PRF is a concentrated suspension of growth factors found in platelets. These growth factors moderate the wound healing and promote tissue regeneration. This article includes case reports of two patients who showed infrabony defects that were treated with combining PRF with allograft. This case report tried to compare the clinical and radiographical outcome obtained by combination of PRF and allograft.

  3. Holographic Chern-Simons defects

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Mitsutoshi [Department of Physics and Astronomy, University of Kentucky,Lexington, KY 40506 (United States); Yukawa Institute for Theoretical Physics, Kyoto University,Kyoto 606-8502 (Japan); Melby-Thompson, Charles M. [Department of Physics, Fudan University,220 Handan Road, 200433 Shanghai (China); Kavli Institute for the Physics and Mathematics of the Universe (WPI),The University of Tokyo Institutes for Advanced Study (UTIAS),The University of Tokyo, Kashiwanoha, Kashiwa, 277-8583 (Japan); Meyer, René [Department of Physics and Astronomy, Stony Brook University,Stony Brook, New York 11794-3800 (United States); Kavli Institute for the Physics and Mathematics of the Universe (WPI),The University of Tokyo Institutes for Advanced Study (UTIAS),The University of Tokyo, Kashiwanoha, Kashiwa, 277-8583 (Japan); Sugimoto, Shigeki [Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto University,Kyoto 606-8502 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI),The University of Tokyo Institutes for Advanced Study (UTIAS),The University of Tokyo, Kashiwanoha, Kashiwa, 277-8583 (Japan)

    2016-06-28

    We study SU(N) Yang-Mills-Chern-Simons theory in the presence of defects that shift the Chern-Simons level from a holographic point of view by embedding the system in string theory. The model is a D3-D7 system in Type IIB string theory, whose gravity dual is given by the AdS soliton background with probe D7 branes attaching to the AdS boundary along the defects. We holographically renormalize the free energy of the defect system with sources, from which we obtain the correlation functions for certain operators naturally associated to these defects. We find interesting phase transitions when the separation of the defects as well as the temperature are varied. We also discuss some implications for the Fractional Quantum Hall Effect and for 2-dimensional QCD.

  4. Toward Intelligent Software Defect Detection

    Science.gov (United States)

    Benson, Markland J.

    2011-01-01

    Source code level software defect detection has gone from state of the art to a software engineering best practice. Automated code analysis tools streamline many of the aspects of formal code inspections but have the drawback of being difficult to construct and either prone to false positives or severely limited in the set of defects that can be detected. Machine learning technology provides the promise of learning software defects by example, easing construction of detectors and broadening the range of defects that can be found. Pinpointing software defects with the same level of granularity as prominent source code analysis tools distinguishes this research from past efforts, which focused on analyzing software engineering metrics data with granularity limited to that of a particular function rather than a line of code.

  5. Cell-extrinsic defective lymphocyte development in Lmna(-/- mice.

    Directory of Open Access Journals (Sweden)

    J Scott Hale

    2010-04-01

    Full Text Available Mutations in the LMNA gene, which encodes all A-type lamins, result in a variety of human diseases termed laminopathies. Lmna(-/- mice appear normal at birth but become runted as early as 2 weeks of age and develop multiple tissue defects that mimic some aspects of human laminopathies. Lmna(-/- mice also display smaller spleens and thymuses. In this study, we investigated whether altered lymphoid organ sizes are correlated with specific defects in lymphocyte development.Lmna(-/- mice displayed severe age-dependent defects in T and B cell development which coincided with runting. Lmna(-/- bone marrow reconstituted normal T and B cell development in irradiated wild-type recipients, driving generation of functional and self-MHC restricted CD4(+ and CD8(+ T cells. Transplantation of Lmna(-/- neonatal thymus lobes into syngeneic wild-type recipients resulted in good engraftment of thymic tissue and normal thymocyte development.Collectively, these data demonstrate that the severe defects in lymphocyte development that characterize Lmna(-/- mice do not result directly from the loss of A-type lamin function in lymphocytes or thymic stroma. Instead, the immune defects in Lmna(-/- mice likely reflect indirect damage, perhaps resulting from prolonged stress due to the striated muscle dystrophies that occur in these mice.

  6. DNA from keratinous tissue

    DEFF Research Database (Denmark)

    Bengtsson, Camilla F.; Olsen, Maja E.; Brandt, Luise Ørsted

    2011-01-01

    Keratinous tissues such as nail, hair, horn, scales and feather have been used as a source of DNA for over 20 years. Particular benefits of such tissues include the ease with which they can be sampled, the relative stability of DNA in such tissues once sampled, and, in the context of ancient...... genetic analyses, the fact that sampling generally causes minimal visual damage to valuable specimens. Even when freshly sampled, however, the DNA quantity and quality in the fully keratinized parts of such tissues is extremely poor in comparison to other tissues such as blood and muscle – although little...... systematic research has been undertaken to characterize how such degradation may relate to sample source. In this review paper we present the current understanding of the quality and limitations of DNA in two key keratinous tissues, nail and hair. The findings indicate that although some fragments of nuclear...

  7. Tissue types (image)

    Science.gov (United States)

    There are 4 basic types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue. Connective tissue ... and binds them together (bone, blood, and lymph tissues). Epithelial tissue provides a covering (skin, the linings of ...

  8. Endoscopic Approach for Tissue Expansion for Different Cosmetic ...

    African Journals Online (AJOL)

    Background/Purpose: The use of tissue expanders in plastic and reconstruction surgery is now well established for large defects in adults & children. Tissue expansion is one of the reconstructive surgeon's alternatives in providing optimal tissue replacement when skin shortage is a major problem. Predesigned plan about ...

  9. Congenital disorders of glycosylation: new defects and still counting

    NARCIS (Netherlands)

    Scott, K.; Gadomski, T.; Kozicz, L.T.; Morava, E.

    2014-01-01

    Almost 50 inborn errors of metabolism have been described due to congenital defects in N-linked glycosylation. These phenotypically diverse disorders typically present as clinical syndromes, affecting multiple systems including the central nervous system, muscle function, transport, regulation,

  10. Soft tissue engineering with micronized-gingival connective tissues.

    Science.gov (United States)

    Noda, Sawako; Sumita, Yoshinori; Ohba, Seigo; Yamamoto, Hideyuki; Asahina, Izumi

    2018-01-01

    The free gingival graft (FGG) and connective tissue graft (CTG) are currently considered to be the gold standards for keratinized gingival tissue reconstruction and augmentation. However, these procedures have some disadvantages in harvesting large grafts, such as donor-site morbidity as well as insufficient gingival width and thickness at the recipient site post-treatment. To solve these problems, we focused on an alternative strategy using micronized tissue transplantation (micro-graft). In this study, we first investigated whether transplantation of micronized gingival connective tissues (MGCTs) promotes skin wound healing. MGCTs (≤100 µm) were obtained by mincing a small piece (8 mm 3 ) of porcine keratinized gingiva using the RIGENERA system. The MGCTs were then transplanted to a full skin defect (5 mm in diameter) on the dorsal surface of immunodeficient mice after seeding to an atelocollagen matrix. Transplantations of atelocollagen matrixes with and without micronized dermis were employed as experimental controls. The results indicated that MGCTs markedly promote the vascularization and epithelialization of the defect area 14 days after transplantation compared to the experimental controls. After 21 days, complete wound closure with low contraction was obtained only in the MGCT grafts. Tracking analysis of transplanted MGCTs revealed that some mesenchymal cells derived from MGCTs can survive during healing and may function to assist in wound healing. We propose here that micro-grafting with MGCTs represents an alternative strategy for keratinized tissue reconstruction that is characterized by low morbidity and ready availability. © 2017 Wiley Periodicals, Inc.

  11. Engineering functional bladder tissues.

    Science.gov (United States)

    Horst, Maya; Madduri, Srinivas; Gobet, Rita; Sulser, Tullio; Milleret, Vinzent; Hall, Heike; Atala, Anthony; Eberli, Daniel

    2013-07-01

    End stage bladder disease can seriously affect patient quality of life and often requires surgical reconstruction with bowel tissue, which is associated with numerous complications. Bioengineering of functional bladder tissue using tissue-engineering techniques could provide new functional tissues for reconstruction. In this review, we discuss the current state of this field and address different approaches to enable physiologic voiding in engineered bladder tissues in the near future. In a collaborative effort, we gathered researchers from four institutions to discuss the current state of functional bladder engineering. A MEDLINE® and PubMed® search was conducted for articles related to tissue engineering of the bladder, with special focus on the cells and biomaterials employed as well as the microenvironment, vascularisation and innervation strategies used. Over the last decade, advances in tissue engineering technology have laid the groundwork for the development of a biological substitute for bladder tissue that can support storage of urine and restore physiologic voiding. Although many researchers have been able to demonstrate the formation of engineered tissue with a structure similar to that of native bladder tissue, restoration of physiologic voiding using these constructs has never been demonstrated. The main issues hindering the development of larger contractile tissues that allow physiologic voiding include the development of correct muscle alignment, proper innervation and vascularization. Tissue engineering of a construct that will support the contractile properties that allow physiologic voiding is a complex process. The combination of smart scaffolds with controlled topography, the ability to deliver multiple trophic factors and an optimal cell source will allow for the engineering of functional bladder tissues in the near future. Copyright © 2012 John Wiley & Sons, Ltd.

  12. Scintigraphic evaluation of the osteoblastic activity of rabbit tibial defects after HYAFF11 membrane application.

    Science.gov (United States)

    Mermerkaya, Musa Uğur; Doral, Mahmut Nedim; Karaaslan, Fatih; Huri, Gazi; Karacavuş, Seyhan; Kaymaz, Burak; Alkan, Erkan

    2016-05-03

    An unfavorable condition for bone healing is the presence of bone defects. Under such conditions, a material can play a role to cover fractured or defective bone. Technological advances now allow for the use of such material. Hyalonect(®) (Fidia Advanced Biopolymers SLR, Italy), a novel membrane comprising knitted fibers of esterified hyaluronan (HYAFF11) can be used to cover fractured or grafted bone and can also serve as a scaffold to keep osteoprogenitor cells in place. The aim of this study was to compare osteoblastic activity by the use of scintigraphic methods in defective rabbit tibias during early-phase bone healing with or without a hyaluronan-based mesh. Two groups (A and B) of New Zealand albino rabbits were used; each group included 10 animals. Operations on all rabbits were performed under general anesthesia. We also resected 10-mm bone segments from each animal's tibial diaphysis. After resection, tibias with defects were fixed using Kirschner wires. In group A, no hyaluronan-based mesh was used. In group B, tibial segmental defects were enclosed with a hyaluronan-based mesh. The rabbits were followed up for 4 weeks postoperatively, after which bone scintigraphic studies were performed on each animal to detect and compare osteoblastic activity. The mean count in the fracture side of the hyaluronan-based mesh group was significantly higher compared to that of the group A (p = 0.019). However, there was no significant difference between group B and control rabbits with respect to the mean count on the intact bone side (p = 0.437). The bone defect (fracture)/intact bone mean count ratio was significantly higher in group B compared to group A (p = 0.008). A hyaluronan-based mesh plays a role in promoting osteoblastic activity. Hyalonect(®) is suitable for restoring tissue continuity whenever the periosteal membrane is structurally impaired or inadequate. Our results demonstrated that, during early-phase bone healing, osteoblastic activity

  13. Structural defects in monocrystalline silicon: from radiation ones to growing and technological

    International Nuclear Information System (INIS)

    Gerasimenko, N.N.; Pavlyuchenko, M.N.; Dzhamanbalin, K.K.

    2001-01-01

    The systematical review of properties and conditions of radiation structures in monocrystalline silicon including own defects (elementary and complex, disordered fields) as well as defect-impurity formations is presented. The most typical examples of principle effects influence of known defects on radiation-induced processes (phase transformations, diffusion and heteration and others are considered. Experimental facts and models of silicon radiation amorphization have been analyzed in comparison of state of the radiation amorphization radiation problem of metals and alloys. The up-to-date status of the problem of the radiation defects physics are discussed, including end-of-range -, n+-, rod-like- defects. The phenomenon self-organization in crystals with defects has been considered. The examples of directed using radiation defects merged in independent trend - defects engineering - are given

  14. A Novel Alpha Cardiac Actin (ACTC1) Mutation Mapping to a Domain in Close Contact with Myosin Heavy Chain Leads to a Variety of Congenital Heart Defects, Arrhythmia and Possibly Midline Defects

    Science.gov (United States)

    Augière, Céline; Mégy, Simon; El Malti, Rajae; Boland, Anne; El Zein, Loubna; Verrier, Bernard; Mégarbané, André; Deleuze, Jean-François; Bouvagnet, Patrice

    2015-01-01

    Background A Lebanese Maronite family presented with 13 relatives affected by various congenital heart defects (mainly atrial septal defects), conduction tissue anomalies and midline defects. No mutations were found in GATA4 and NKX2-5. Methods and Results A set of 399 poly(AC) markers was used to perform a linkage analysis which peaked at a 2.98 lod score on the long arm of chromosome 15. The haplotype analysis delineated a 7.7 meganucleotides genomic interval which included the alpha-cardiac actin gene (ACTC1) among 36 other protein coding genes. A heterozygous missense mutation was found (c.251T>C, p.(Met84Thr)) in the ACTC1 gene which changed a methionine residue conserved up to yeast. This mutation was absent from 1000 genomes and exome variant server database but segregated perfectly in this family with the affection status. This mutation and 2 other ACTC1 mutations (p.(Glu101Lys) and p.(Met125Val)) which result also in congenital heart defects are located in a region in close apposition to a myosin heavy chain head region by contrast to 3 other alpha-cardiac actin mutations (p.(Ala297Ser),p.(Asp313His) and p.(Arg314His)) which result in diverse cardiomyopathies and are located in a totally different interaction surface. Conclusions Alpha-cardiac actin mutations lead to congenital heart defects, cardiomyopathies and eventually midline defects. The consequence of an ACTC1 mutation may in part be dependent on the interaction surface between actin and myosin. PMID:26061005

  15. A Novel Alpha Cardiac Actin (ACTC1 Mutation Mapping to a Domain in Close Contact with Myosin Heavy Chain Leads to a Variety of Congenital Heart Defects, Arrhythmia and Possibly Midline Defects.

    Directory of Open Access Journals (Sweden)

    Céline Augière

    Full Text Available A Lebanese Maronite family presented with 13 relatives affected by various congenital heart defects (mainly atrial septal defects, conduction tissue anomalies and midline defects. No mutations were found in GATA4 and NKX2-5.A set of 399 poly(AC markers was used to perform a linkage analysis which peaked at a 2.98 lod score on the long arm of chromosome 15. The haplotype analysis delineated a 7.7 meganucleotides genomic interval which included the alpha-cardiac actin gene (ACTC1 among 36 other protein coding genes. A heterozygous missense mutation was found (c.251T>C, p.(Met84Thr in the ACTC1 gene which changed a methionine residue conserved up to yeast. This mutation was absent from 1000 genomes and exome variant server database but segregated perfectly in this family with the affection status. This mutation and 2 other ACTC1 mutations (p.(Glu101Lys and p.(Met125Val which result also in congenital heart defects are located in a region in close apposition to a myosin heavy chain head region by contrast to 3 other alpha-cardiac actin mutations (p.(Ala297Ser,p.(Asp313His and p.(Arg314His which result in diverse cardiomyopathies and are located in a totally different interaction surface.Alpha-cardiac actin mutations lead to congenital heart defects, cardiomyopathies and eventually midline defects. The consequence of an ACTC1 mutation may in part be dependent on the interaction surface between actin and myosin.

  16. Main properties of nanocrystalline hydroxyapatite as a bone graft material in treatment of periodontal defects. A review of literature

    International Nuclear Information System (INIS)

    Bayani, Mojtaba; Torabi, Sepehr; Shahnaz, Aysan; Pourali, Mohammad

    2017-01-01

    This study aims to provide a literature review on nanocrystalline hydroxyapatite (n-HA). n-HA constitutes the principle inorganic part of hard tissues. Therefore, preparation of commercial synthetic analogues, the so-called ‘biomimetic’, has gained a lot of attention since it can precisely mimic the physicochemical features of biological apatite compounds. Due to its improved osseointegrative properties, n-HA may represent a promising class of bone graft materials. n-HA binds to the bone and by stimulation of osteoblast activity and enhancing local growth factors it improves bone healing. Periodontitis is an inflammatory condition in response to microbial plaque that leads to periodontal tissue destruction and osseous defects in alveolar bone. A review of the extant literature reveals that n-HA has certain advantages in periodontal tissue regeneration including minimal patient morbidity, better biocompatibility, and lack of toxicity

  17. Role of free tissue transfer in management of chronic venous ulcer

    Directory of Open Access Journals (Sweden)

    Reddy K

    2004-01-01

    Full Text Available Most of the venous ulcers will heal with the treatment of primary venous problem. But a few patients will have refractory, recurrent chronic venous ulcers causing inconvenience to the patients in terms of loss of productive working hours. There is no standard method available for treatment of this chronic problem. Our modality of treatment includes wide excision of ulcer, ligation of incompetent perforators and coverage of defect with well vascularized tissue by free tissue transfer. We have analyzed this form of treatment in five patients with satisfactory result.

  18. Early rehabilitation of facial defects using interim removable prostheses: A clinical case report

    Directory of Open Access Journals (Sweden)

    Vivekanandhan Ramkumar

    2013-01-01

    Full Text Available Surgical resection of neoplasms or malformations of the face may result in defects that are not amenable to immediate surgical reconstruction. Such defects can have a severe adverse effect on patient perceptions of body image and self-esteem. In these cases, the use of an interim removable facial prosthesis can offer a rapid alternative treatment solution. The patient may then resume social interactions more comfortably while permitting easy access to the facial defect to observe tissue healing while awaiting definitive rehabilitation. This article presents a case report describing the use of interim nasal prostheses to provide rapid patient rehabilitation of facial defects.

  19. Cardiac Defects and Results of Cardiac Surgery in 22q11.2 Deletion Syndrome

    Science.gov (United States)

    Carotti, Adriano; Digilio, Maria Cristina; Piacentini, Gerardo; Saffirio, Claudia; Di Donato, Roberto M.; Marino, Bruno

    2008-01-01

    Specific types and subtypes of cardiac defects have been described in children with 22q11.2 deletion syndrome as well as in other genetic syndromes. The conotruncal heart defects occurring in patients with 22q11.2 deletion syndrome include tetralogy of Fallot, pulmonary atresia with ventricular septal defect, truncus arteriosus, interrupted aortic…

  20. Advances in Meniscal Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Umile Giuseppe Longo

    2012-01-01

    Full Text Available Meniscal tears are the most common knee injuries and have a poor ability of healing. In the last few decades, several techniques have been increasingly used to optimize meniscal healing. Current research efforts of tissue engineering try to combine cell-based therapy, growth factors, gene therapy, and reabsorbable scaffolds to promote healing of meniscal defects. Preliminary studies did not allow to draw definitive conclusions on the use of these techniques for routine management of meniscal lesions. We performed a review of the available literature on current techniques of tissue engineering for the management of meniscal tears.

  1. Identification of biochemical features of defective Coffea arabica L. beans.

    Science.gov (United States)

    Casas, María I; Vaughan, Michael J; Bonello, Pierluigi; McSpadden Gardener, Brian; Grotewold, Erich; Alonso, Ana P

    2017-05-01

    Coffee organoleptic properties are based in part on the quality and chemical composition of coffee beans. The presence of defective beans during processing and roasting contribute to off flavors and reduce overall cup quality. A multipronged approach was undertaken to identify specific biochemical markers for defective beans. To this end, beans were split into defective and non-defective fractions and biochemically profiled in both green and roasted states. A set of 17 compounds in green beans, including organic acids, amino acids and reducing sugars; and 35 compounds in roasted beans, dominated by volatile compounds, organic acids, sugars and sugar alcohols, were sufficient to separate the defective and non-defective fractions. Unsorted coffee was examined for the presence of the biochemical markers to test their utility in detecting defective beans. Although the green coffee marker compounds were found in all fractions, three of the roasted coffee marker compounds (1-methylpyrrole, 5-methyl- 2-furfurylfuran, and 2-methylfuran) were uniquely present in defective fractions. Published by Elsevier Ltd.

  2. 2010 Defects in Semiconductors GRC

    Energy Technology Data Exchange (ETDEWEB)

    Shengbai Zhang

    2011-01-06

    Continuing its tradition of excellence, this Gordon Conference will focus on research at the forefront of the field of defects in semiconductors. The conference will have a strong emphasis on the control of defects during growth and processing, as well as an emphasis on the development of novel defect detection methods and first-principles defect theories. Electronic, magnetic, and optical properties of bulk, thin film, and nanoscale semiconductors will be discussed in detail. In contrast to many conferences, which tend to focus on specific semiconductors, this conference will deal with point and extended defects in a broad range of electronic materials. This approach has proved to be extremely fruitful for advancing fundamental understanding in emerging materials such as wide-band-gap semiconductors, oxides, sp{sup 2} carbon based-materials, and photovoltaic/solar cell materials, and in understanding important defect phenomena such as doping bottleneck in nanostructures and the diffusion of defects and impurities. The program consists of about twenty invited talks and a number of contributed poster sessions. The emphasis should be on work which has yet to be published. The large amount of discussion time provides an ideal forum for dealing with topics that are new and/or controversial.

  3. DEFECTS SIMULATION OF ROLLING STRIP

    Directory of Open Access Journals (Sweden)

    Rudolf Mišičko

    2009-06-01

    Full Text Available The defects in the continuous casting slabs can be developed or kept down in principle by rolling technology, especially depend to sort, size and distribution of primary defects, as well as used of rolling parameters. Scope of the article is on observation behavior artificial surface and undersurface defects (scores without filler (surface defects and filling by oxides and casting powder (subsurface defects. First phase of hot rolling process have been done by software simulation DEFORM 3D setting to the limited condition for samples with surface defects. Samples of material with low-carbon steel of sizes h x b x l have been chosen and the surface defects shape „U” and „V” of scores have been injected artificially by software. The process of rolling have been simulated on the deformation temperatures 1200°C and 900°C, whereas on the both of this deformation temperatures have been applied amount of deformation 10 and 50 %. With respect to the process of computer simulation, it is not possible to truthful real oxidation condition (physical – chemical process during heat of metal, in the second phase of our investigation have been observed influence of oxides and casting powders inside the scores for a defect behavior in plastic deformation process (hot and cold rolling process in laboratory condition. The basic material was STN steel class 11 375, cladding material was steel on the bases C-Mn-Nb-V. Scores have been filled by scales to get from the heating temperatures (1100°C a 1250°C, varied types of casting powders, if you like mixture of scale and casting powders in the rate 1:4. The joint of the basic and cladding material have been done by peripheral welded joint. Experiment results from both phases are pointed on the evolution of original typology defects in rolling process.

  4. The distally-based island ulnar artery perforator flap for wrist defects

    Directory of Open Access Journals (Sweden)

    Karki Durga

    2007-01-01

    Full Text Available Background: Reconstruction of soft tissue defects around the wrist with exposed tendons, joints, nerves and bone represents a challenge to plastic surgeons, and such defects necessitate flap coverage to preserve hand functions and to protect its vital structures. We evaluated the use of a distally-based island ulnar artery perforator flap in patients with volar soft tissue defects around the wrist. Materials and Methods: Between June 2004 and June 2006, seven patients of soft tissue defects on the volar aspect of the wrist underwent distally-based island ulnar artery perforator flap. Out of seven patients, five were male and two patients were female. This flap was used in the reconstruction of the post road traffic accident defects in four patients and post electric burn defects in three patients. Flap was raised on one or two perforators and was rotated to 180°. Results: All flaps survived completely. Donor sites were closed primarily without donor site morbidity. Conclusion: The distally-based island Ulnar artery perforator flap is convenient, reliable, easy to manage and is a single-stage technique for reconstructing soft tissue defects of the volar aspect of the wrist. Early use of this flap allows preservation of vital structures, decreases morbidity and allows for early rehabilitation.

  5. Positron studies of defected metals, metallic surfaces

    International Nuclear Information System (INIS)

    Bansil, A.

    1991-01-01

    Specific problems proposed under this project included the treatment of electronic structure and momentum density in various disordered and defected systems. Since 1987, when the new high-temperature superconductors were discovered, the project focused extensively on questions concerning the electronic structure and Fermiology of high-T c superconductors, in particular, (i) momentum density and positron experiments, (ii) angle-resolved photoemission intensities, (iii) effects of disorder and substitutions in the high-T c 's

  6. Theory of radiation induced defect production

    International Nuclear Information System (INIS)

    Robinson, M.T.

    1975-10-01

    The theory of defect production in solids by neutron irradiation is reviewed, including discussions of the nuclear reactions which produce the primary recoils and the loss of energy from the displacement cascade by electron excitations. The theoretical predictions are compared with the limited available experiments on thermal and fast neutron irradiation. The results are in rough agreement in most instances, but further improvements in the theory are clearly needed

  7. The role of point defects and defect complexes in silicon device processing. Summary report and papers

    Energy Technology Data Exchange (ETDEWEB)

    Sopori, B.; Tan, T.Y.

    1994-08-01

    This report is a summary of a workshop hold on August 24--26, 1992. Session 1 of the conference discussed characteristics of various commercial photovoltaic silicon substrates, the nature of impurities and defects in them, and how they are related to the material growth. Session 2 on point defects reviewed the capabilities of theoretical approaches to determine equilibrium structure of defects in the silicon lattice arising from transitional metal impurities and hydrogen. Session 3 was devoted to a discussion of the surface photovoltaic method for characterizing bulk wafer lifetimes, and to detailed studies on the effectiveness of various gettering operations on reducing the deleterious effects of transition metals. Papers presented at the conference are also included in this summary report.

  8. When Your Baby Has a Birth Defect

    Science.gov (United States)

    ... Search English Español When Your Baby Has a Birth Defect KidsHealth / For Parents / When Your Baby Has ... to help you and your child. What Are Birth Defects? Birth defects (also called congenital anomalies) are ...

  9. Reconstruction of Defects After Fournier Gangrene: A Systematic Review.

    Science.gov (United States)

    Karian, Laurel S; Chung, Stella Y; Lee, Edward S

    2015-01-01

    Reconstruction of scrotal defects after Fournier gangrene is often achieved with skin grafts or flaps, but there is no general consensus on the best method of reconstruction or how to approach the exposed testicle. We systematically reviewed the literature addressing methods of reconstruction of Fournier defects after debridement. PubMed and Cochrane databases were searched from 1950 to 2013. Inclusion criteria were reconstruction for Fournier defects, patients 18 to 90 years old, and reconstructive complication rates reported as whole numbers or percentages. Exclusion criteria were studies focused on methods of debridement or other phases of care rather than reconstruction, studies with fewer than 5 male patients with Fournier defects, literature reviews, and articles not in English. The initial search yielded 982 studies, which was refined to 16 studies with a total pool of 425 patients. There were 25 (5.9%) patients with defects that healed by secondary intention, 44 (10.4%) with delayed primary closure, 36 (8.5%) with implantation of the testicle in a medial thigh pocket, 6 (1.4%) with loose wound approximation, 96 (22.6%) with skin grafts, 68 (16.0%) with scrotal advancement flaps, 128 (30.1%) with flaps, and 22 (5.2%) with flaps or skin grafts in combination with tissue adhesives. Four outcomes were evaluated: number of patients, defect size, method of reconstruction, and wound-healing complications. Most reconstructive techniques provide reliable coverage and protection of testicular function with an acceptable cosmetic result. There is no conclusive evidence to support flap coverage of exposed testes rather than skin graft. A reconstructive algorithm is proposed. Skin grafting or flap reconstruction is recommended for defects larger than 50% of the scrotum or extending beyond the scrotum, whereas scrotal advancement flap reconstruction or healing by secondary intention is best for defects confined to less than 50% of the scrotum that cannot be closed

  10. Tissue Photolithography

    Science.gov (United States)

    Wade, Lawrence A.; Kartalov, Emil; Shibata, Darryl; Taylor, Clive

    2011-01-01

    Tissue lithography will enable physicians and researchers to obtain macromolecules with high purity (greater than 90 percent) from desired cells in conventionally processed, clinical tissues by simply annotating the desired cells on a computer screen. After identifying the desired cells, a suitable lithography mask will be generated to protect the contents of the desired cells while allowing destruction of all undesired cells by irradiation with ultraviolet light. The DNA from the protected cells can be used in a number of downstream applications including DNA sequencing. The purity (i.e., macromolecules isolated form specific cell types) of such specimens will greatly enhance the value and information of downstream applications. In this method, the specific cells are isolated on a microscope slide using photolithography, which will be faster, more specific, and less expensive than current methods. It relies on the fact that many biological molecules such as DNA are photosensitive and can be destroyed by ultraviolet irradiation. Therefore, it is possible to protect the contents of desired cells, yet destroy undesired cells. This approach leverages the technologies of the microelectronics industry, which can make features smaller than 1 micrometer with photolithography. A variety of ways has been created to achieve identification of the desired cell, and also to designate the other cells for destruction. This can be accomplished through chrome masks, direct laser writing, and also active masking using dynamic arrays. Image recognition is envisioned as one method for identifying cell nuclei and cell membranes. The pathologist can identify the cells of interest using a microscopic computerized image of the slide, and appropriate custom software. In one of the approaches described in this work, the software converts the selection into a digital mask that can be fed into a direct laser writer, e.g. the Heidelberg DWL66. Such a machine uses a metalized glass plate (with

  11. Defect detection based on extreme edge of defective region histogram

    Directory of Open Access Journals (Sweden)

    Zouhir Wakaf

    2018-01-01

    Full Text Available Automatic thresholding has been used by many applications in image processing and pattern recognition systems. Specific attention was given during inspection for quality control purposes in various industries like steel processing and textile manufacturing. Automatic thresholding problem has been addressed well by the commonly used Otsu method, which provides suitable results for thresholding images based on a histogram of bimodal distribution. However, the Otsu method fails when the histogram is unimodal or close to unimodal. Defects have different shapes and sizes, ranging from very small to large. The gray-level distributions of the image histogram can vary between unimodal and multimodal. Furthermore, Otsu-revised methods, like the valley-emphasis method and the background histogram mode extents, which overcome the drawbacks of the Otsu method, require preprocessing steps and fail to use the general threshold for multimodal defects. This study proposes a new automatic thresholding algorithm based on the acquisition of the defective region histogram and the selection of its extreme edge as the threshold value to segment all defective objects in the foreground from the image background. To evaluate the proposed defect-detection method, common standard images for experimentation were used. Experimental results of the proposed method show that the proposed method outperforms the current methods in terms of defect detection.

  12. The osmotic tissue expander : a three-year clinical experience

    NARCIS (Netherlands)

    Obdeijn, Miryam C.; Nicolai, Jean-Philippe A.; Werker, Paul M. N.

    Closure of defects after trauma or excision of neoplasms is a basic skill in plastic surgery. Local, regional and distant flaps lead to additional scars. Skin recruitment by serial excision or skin expansion is a Less damaging option for defects that must be closed. Advantages of tissue expansion

  13. First-Principles Investigations of Defects in Minerals

    Science.gov (United States)

    Verma, Ashok K.

    2011-07-01

    The ideal crystal has an infinite 3-dimensional repetition of identical units which may be atoms or molecules. But real crystals are limited in size and they have disorder in stacking which as called defects. Basically three types of defects exist in solids: 1) point defects, 2) line defects, and 3) surface defects. Common point defects are vacant lattice sites, interstitial atoms and impurities and these are known to influence strongly many solid-state transport properties such as diffusion, electrical conduction, creep, etc. In thermal equilibrium point defects concentrations are determined by their formation enthalpies and their movement by their migration barriers. Line and surface defects are though absent from the ideal crystal in thermal equilibrium due to higher energy costs but they are invariably present in all real crystals. Line defects include edge-, screw- and mixed-dislocations and their presence is essential in explaining the mechanical strength and deformation of real crystals. Surface defects may arise at the boundary between two grains, or small crystals, within a larger crystal. A wide variety of grain boundaries can form in a polycrystal depending on factors such growth conditions and thermal treatment. In this talk we will present our first-principles density functional theory based defect studies of SiO2 polymorphs (stishovite, CaCl2-, α-PbO2-, and pyrite-type), Mg2SiO4 polymorphs (forsterite, wadsleyite and ringwoodite) and MgO [1-3]. Briefly, several native point defects including vacancies, interstitials, and their complexes were studied in silica polymorphs upto 200 GPa. Their values increase by a factor of 2 over the entire pressure range studied with large differences in some cases between different phases. The Schottky defects are energetically most favorable at zero pressure whereas O-Frenkel pairs become systematically more favorable at pressures higher than 20 GPa. The geometric and electronic structures of defects and migrating

  14. Is Maternal Parity an Independent Risk Factor for Birth Defects?

    Science.gov (United States)

    Duong, Hao T.; Hoyt, Adrienne T.; Carmichael, Suzan L.; Gilboa, Suzanne M.; Canfield, Mark A.; Case, Amy; McNeese, Melanie L.; Waller, Dorothy Kim

    2015-01-01

    BACKGROUND Although associations between maternal parity and birth defects have been observed previously, few studies have focused on the possibility that parity is an independent risk factor for birth defects. We investigated the relation between levels of parity and a range of birth defects, adjusting each defect group for the same covariates. METHODS We included infants who had an estimated delivery date between 1997 and 2007 and participated in the National Birth Defects Prevention Study, a multisite case-control study. Cases included infants or fetuses belonging to 38 phenotypes of birth defects (n = 17,908), and controls included infants who were unaffected by a major birth defect (n = 7173). Odds ratios (ORs) were adjusted for 12 covariates using logistic regression. RESULTS Compared with primiparous mothers, nulliparous mothers were more likely to have infants with amniotic band sequence, hydrocephaly, esophageal atresia, hypospadias, limb reduction deficiencies, diaphragmatic hernia, omphalocele, gastroschisis, tetralogy of Fallot, and septal cardiac defects, with significant ORs (1.2 to 2.3). Compared with primiparous mothers, multiparous mothers had a significantly increased risk of omphalocele, with an OR of 1.5, but had significantly decreased risk of hypospadias and limb reduction deficiencies, with ORs of 0.77 and 0.77. CONCLUSIONS Nulliparity was associated with an increased risk of specific phenotypes of birth defects. Most of the phenotypes associated with nulliparity in this study were consistent with those identified by previous studies. Research into biologic or environmental factors that are associated with nulliparity may be helpful in explaining some or all of these associations. PMID:22371332

  15. Birth Defects Data and Statistics

    Science.gov (United States)

    ... Submit" /> Information For… Media Policy Makers Data & Statistics Recommend on Facebook Tweet Share Compartir On This ... and critical. Read below for the latest national statistics on the occurrence of birth defects in the ...

  16. What Are Congenital Heart Defects?

    Science.gov (United States)

    ... of a Normal Heart and a Heart With Tetralogy of Fallot Figure A shows the structure and blood flow ... shows a heart with the four defects of tetralogy of Fallot. Babies and children who have tetralogy of Fallot ...

  17. Birth Defects Research and Tracking

    Science.gov (United States)

    ... Environmental public health tracking is the ongoing collection, integration, analysis, interpretation, and dissemination of data on environmental ... 2016) Key Findings: Gastroschisis – a Serious Birth Defect – Continues to Increase New CDC research shows that the ...

  18. Defects in semiconductors

    International Nuclear Information System (INIS)

    Tilly, L.

    1993-04-01

    In this thesis, experimental results of the transition metals Ti, V, Nb, Mo, and W as impurity centres in silicon are presented. Transition metal doping was accomplished by ion implantation. Emphasis is put on energy level position, electrical and optical properties of the encountered defect levels. Junction space charge methods (JSCM) such as DLTS, photocapacitance and photocurrent techniques are employed. Three energy levels are found for the 3d-transition metals Ti(E c -0.06eV, E c -0.30eV, E v +0.26) and V(E c -0.21eV, E c -0,48e, E v +0.36eV), and for the 4d-element Nb(E c -0.29eV, E c -0.58eV, E v +0.163eV) in Silicon, whereas only one transition metal induced level is found for Mo(E v +0.30eV) and W(E v +0.38eV) respectively. Electrical and optical characteristics of Si 1-x Ge x ,0.7 7 cm -2 . The solvent Bi, used in the LPE-process, is found to be the dominant impurity element. Furthermore, liquid phase epitaxy of high purity In 0.53 Ga 0.57 As on InP, together with the properties of the Cu-induced acceptor in this material are examined. Free electron concentrations of n=5x10 14 cm -3 and electron Hall-mobilities of μ 77K = 44000 cm 2 /Vs are achieved. The energy level position of the Cu-acceptor is found to be E v +0.025eV. Photoluminescence and Hall-effect measurements, together with JSCM are the main characterization methods used. The band linups of In 0.53 Ga 0.47 As with GaAs and with InP are determined according to the Cu-acceptor energy level position in these materials. Additionally, the hydrostatic pressure dependence of the Cu-acceptor energy level position in In 0.53 Ga 0.47 As is examined. (103 refs.)

  19. Skeletal muscle tissue engineering: methods to form skeletal myotubes and their applications.

    Science.gov (United States)

    Ostrovidov, Serge; Hosseini, Vahid; Ahadian, Samad; Fujie, Toshinori; Parthiban, Selvakumar Prakash; Ramalingam, Murugan; Bae, Hojae; Kaji, Hirokazu; Khademhosseini, Ali

    2014-10-01

    Skeletal muscle tissue engineering (SMTE) aims to repair or regenerate defective skeletal muscle tissue lost by traumatic injury, tumor ablation, or muscular disease. However, two decades after the introduction of SMTE, the engineering of functional skeletal muscle in the laboratory still remains a great challenge, and numerous techniques for growing functional muscle tissues are constantly being developed. This article reviews the recent findings regarding the methodology and various technical aspects of SMTE, including cell alignment and differentiation. We describe the structure and organization of muscle and discuss the methods for myoblast alignment cultured in vitro. To better understand muscle formation and to enhance the engineering of skeletal muscle, we also address the molecular basics of myogenesis and discuss different methods to induce myoblast differentiation into myotubes. We then provide an overview of different coculture systems involving skeletal muscle cells, and highlight major applications of engineered skeletal muscle tissues. Finally, potential challenges and future research directions for SMTE are outlined.

  20. Skeletal Muscle Tissue Engineering: Methods to Form Skeletal Myotubes and Their Applications

    Science.gov (United States)

    Ostrovidov, Serge; Hosseini, Vahid; Ahadian, Samad; Fujie, Toshinori; Parthiban, Selvakumar Prakash; Ramalingam, Murugan; Bae, Hojae; Kaji, Hirokazu

    2014-01-01

    Skeletal muscle tissue engineering (SMTE) aims to repair or regenerate defective skeletal muscle tissue lost by traumatic injury, tumor ablation, or muscular disease. However, two decades after the introduction of SMTE, the engineering of functional skeletal muscle in the laboratory still remains a great challenge, and numerous techniques for growing functional muscle tissues are constantly being developed. This article reviews the recent findings regarding the methodology and various technical aspects of SMTE, including cell alignment and differentiation. We describe the structure and organization of muscle and discuss the methods for myoblast alignment cultured in vitro. To better understand muscle formation and to enhance the engineering of skeletal muscle, we also address the molecular basics of myogenesis and discuss different methods to induce myoblast differentiation into myotubes. We then provide an overview of different coculture systems involving skeletal muscle cells, and highlight major applications of engineered skeletal muscle tissues. Finally, potential challenges and future research directions for SMTE are outlined. PMID:24320971

  1. Cell-Derived Extracellular Matrix: Basic Characteristics and Current Applications in Orthopedic Tissue Engineering.

    Science.gov (United States)

    Zhang, Weixiang; Zhu, Yun; Li, Jia; Guo, Quanyi; Peng, Jiang; Liu, Shichen; Yang, Jianhua; Wang, Yu

    2016-06-01

    The extracellular matrix (ECM) is a dynamic and intricate microenvironment with excellent biophysical, biomechanical, and biochemical properties, which can directly or indirectly regulate cell proliferation, adhesion, migration, and differentiation, as well as plays key roles in homeostasis and regeneration of tissues and organs. The ECM has attracted a great deal of attention with the rapid development of tissue engineering in the field of regenerative medicine. Tissue-derived ECM scaffolds (also referred to as decellularized tissues and whole organs) are considered a promising therapy for the repair of musculoskeletal defects, including those that are widely used in orthopedics, although there are a few shortcomings. Similar to tissue-derived ECM scaffolds, cell-derived ECM scaffolds also have highly advantageous biophysical and biochemical properties, in particular their ability to be produced in vitro from a number of different cell types. Furthermore, cell-derived ECM scaffolds more closely resemble native ECM microenvironments. The products of cell-derived ECM have a wide range of biomedical applications; these include reagents for cell culture substrates and biomaterials for scaffolds, hybrid scaffolds, and living cell sheet coculture systems. Although cell-derived ECM has only just begun to be investigated, it has great potential as a novel approach for cell-based tissue repair in orthopedic tissue engineering. This review summarizes and analyzes the various types of cell-derived ECM products applied in cartilage, bone, and nerve tissue engineering in vitro or in vivo and discusses future directions for investigation of cell-derived ECM.

  2. One step automated unpatterned wafer defect detection and classification

    International Nuclear Information System (INIS)

    Dou Lie; Kesler, Daniel; Bruno, William; Monjak, Charles; Hunt, Jim

    1998-01-01

    Automated detection and classification of crystalline defects on micro-grade silicon wafers is extremely important for integrated circuit (IC) device yield. High training cost, limited capability of classifying defects, increasing possibility of contamination, and unexpected human mistakes necessitate the need to replace the human visual inspection with automated defect inspection. The Laser Scanning Surface Inspection Systems (SSISs) equipped with the Reconvergent Specular Detection (RSD) apparatus are widely used for final wafer inspection. RSD, more commonly known as light channel detection (LC), is capable of detecting and classifying material defects by analyzing information from two independent phenomena, light scattering and reflecting. This paper presents a new technique including a new type of light channel detector to detect and classify wafer surface defects such as slipline dislocation, Epi spikes, Pits, and dimples. The optical system to study this technique consists of a particle scanner to detect and quantify light scattering events from contaminants on the wafer surface and a RSD apparatus (silicon photo detector). Compared with the light channel detector presently used in the wafer fabs, this new light channel technique provides higher sensitivity for small defect detection and more defect scattering signatures for defect classification. Epi protrusions (mounds and spikes), slip dislocations, voids, dimples, and some other common defect features and contamination on silicon wafers are studied using this equipment. The results are compared quantitatively with that of human visual inspection and confirmed by microscope or AFM. This new light channel technology could provide the real future solution to the wafer manufacturing industry for fully automated wafer inspection and defect characterization

  3. Possible role of mechanical force in regulating regeneration of the vascularized fat flap inside a tissue engineering chamber.

    Science.gov (United States)

    Ye, Yuan; Yuan, Yi; Lu, Feng; Gao, Jianhua

    2015-12-01

    In plastic and reconstructive surgery, adipose tissue is widely used as effective filler for tissue defects. Strategies for treating soft tissue deficiency, which include free adipose tissue grafts, use of hyaluronic acid, collagen injections, and implantation of synthetic materials, have several clinical limitations. With the aim of overcoming these limitations, researchers have recently utilized tissue engineering chambers to produce large volumes of engineered vascularized fat tissue. However, the process of growing fat tissue in a chamber is still relatively limited, and can result in unpredictable or dissatisfactory final tissue volumes. Therefore, detailed understanding of the process is both necessary and urgent. Many studies have shown that mechanical force can change the function of cells via mechanotransduction. Here, we hypothesized that, besides the inflammatory response, one of the key factors to control the regeneration of vascularized fat flap inside a tissue engineering chamber might be the balance of mechanical forces. To test our hypothesis, we intend to change the balance of forces by means of measures in order to make the equilibrium point in favor of the direction of regeneration. If those measures proved to be feasible, they could be applied in clinical practice to engineer vascularized adipose tissue of predictable size and shape, which would in turn help in the advancement of tissue engineering. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Topological defects from the multiverse

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jun; Vilenkin, Alexander [Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); Blanco-Pillado, Jose J. [Department of Theoretical Physics, University of the Basque Country UPV/EHU, 48080 Bilbao (Spain); Garriga, Jaume, E-mail: jun.zhang@tufts.edu, E-mail: josejuan.blanco@ehu.es, E-mail: jaume.garriga@ub.edu, E-mail: vilenkin@cosmos.phy.tufts.edu [Departament de Fisica Fonamental i Institut de Ciencies del Cosmos, Universitat de Barcelona, Marti i Franques, 1, 08028, Barcelona (Spain)

    2015-05-01

    Many theories of the early universe predict the existence of a multiverse where bubbles continuously nucleate giving rise to observers in their interior. In this paper, we point out that topological defects of several dimensionalities will also be produced in de Sitter like regions of the multiverse. In particular, defects could be spontaneously nucleated in our parent vacuum. We study the evolution of these defects as they collide with and propagate inside of our bubble. We estimate the present distribution of defects in the observable part of the universe. The expected number of such nearby defects turns out to be quite small, even for the highest nucleation rate. We also study collisions of strings and domain walls with our bubble in our past light cone. We obtain simulated full-sky maps of the loci of such collisions, and find their angular size distribution. Similarly to what happens in the case of bubble collisions, the prospect of detecting any collisions of our bubble with ambient defects is greatly enhanced in the case where the cosmological constant of our parent vacuum is much higher than the vacuum energy density during inflation in our bubble.

  5. Topological defects from the multiverse

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jun [Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States); Blanco-Pillado, Jose J. [Department of Theoretical Physics, University of the Basque Country UPV/EHU, 48080 Bilbao (Spain); IKERBASQUE, Basque Foundation for Science, 48013, Bilbao (Spain); Garriga, Jaume [Departament de Fisica Fonamental i Institut de Ciencies del Cosmos, Universitat de Barcelona, Marti i Franques, 1, 08028, Barcelona (Spain); Vilenkin, Alexander [Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States)

    2015-05-28

    Many theories of the early universe predict the existence of a multiverse where bubbles continuously nucleate giving rise to observers in their interior. In this paper, we point out that topological defects of several dimensionalities will also be produced in de Sitter like regions of the multiverse. In particular, defects could be spontaneously nucleated in our parent vacuum. We study the evolution of these defects as they collide with and propagate inside of our bubble. We estimate the present distribution of defects in the observable part of the universe. The expected number of such nearby defects turns out to be quite small, even for the highest nucleation rate. We also study collisions of strings and domain walls with our bubble in our past light cone. We obtain simulated full-sky maps of the loci of such collisions, and find their angular size distribution. Similarly to what happens in the case of bubble collisions, the prospect of detecting any collisions of our bubble with ambient defects is greatly enhanced in the case where the cosmological constant of our parent vacuum is much higher than the vacuum energy density during inflation in our bubble.

  6. Electrical fingerprint of pipeline defects

    International Nuclear Information System (INIS)

    Mica, Isabella; Polignano, Maria Luisa; Marco, Cinzia De

    2004-01-01

    Pipeline defects are dislocations that connect the source region of the transistor with the drain region. They were widely reported to occur in CMOS, BiCMOS devices and recently in SOI technologies. They can reduce device yield either by affecting the devices functionality or by increasing the current consumption under stand-by conditions. In this work the electrical fingerprint of these dislocations is studied, its purpose is to enable us to identify these defects as the ones responsible for device failure. It is shown that the pipeline defects are responsible for a leakage current from source to drain in the transistors. This leakage has a resistive characteristic and it is lightly modulated by the body bias. It is not sensitive to temperature; vice versa the off-current of a good transistor exhibits the well-known exponential dependence on 1/T. The emission spectrum of these defects was studied and compared with the spectrum of a good transistor. The paper aims to show that the spectrum of a defective transistor is quite peculiar; it shows well defined peaks, whereas the spectrum of a good transistor under saturation conditions is characterized by a broad spectral light emission distribution. Finally the deep-level transient spectroscopy (DLTS) is tried on defective diodes

  7. Hard-tissue alterations following immediate implant placement in extraction sites.

    Science.gov (United States)

    Botticelli, Daniele; Berglundh, Tord; Lindhe, Jan

    2004-10-01

    The marginal gap that may occur following implant installation in an extraction socket may be resolved by hard-tissue fill during healing. To study dimensional alterations of hard tissues that occur following tooth extraction and immediate placement of implants. Eighteen subjects with a total of 21 teeth scheduled for extraction were included. Following flap elevation and the removal of a tooth and implant installation, clinical measurements were made to characterize the dimension of the surrounding bone walls, as well as the marginal defect. No membranes or filler material was used. The flaps were subsequently replaced and secured with sutures in such a way that the healing cap of the implant was exposed to the oral environment. After 4 months of healing a re-entry procedure was performed and the clinical measurements were repeated. Fifty-two marginal defects exceeding 3 mm were present at baseline: 21 at buccal, 17 at lingual/palatal, and 14 at approximal surfaces. At the re-entry eight defects exceeding 3.0 mm remained. During the 4 months of healing, the bone walls of the extraction underwent marked change. The horizontal resorption of the buccal bone dimension amounted to about 56%. The corresponding resorption of the lingual/palatal bone was 30%. The vertical bone crest resorption amounted to 0.3+/-0.6 mm (buccal), 0.6+/-1.0 mm (lingual/palatal), 0.2+/-0.7 mm (mesial), and 0.5+/-0.9 mm (distal). The marginal gap that occurred between the metal rod and the bone tissue following implant installation in an extraction socket may predictably heal with new bone formation and defect resolution. The current results further documented that marginal gaps in buccal and palatal/lingual locations were resolved through new bone formation from the inside of the defects and substantial bone resorption from the outside of the ridge. Copyright Blackwell Munksgaard, 2004

  8. [TIBIAL PERIOSTEAL FLAP PEDICLED WITH INTERMUSCULAR BRANCH OF POSTERIOR TIBIAL VESSELS COMBINED WITH AUTOLOGOUS BONE GRAFT FOR TIBIAL BONE DEFECT].

    Science.gov (United States)

    Ni, Yulong; Gao, Shunhong; Zhang, Jingyu; Dong, Huishuang; Zhang, Yunpeng; Fu, Jiansong

    2015-10-01

    To investigate the effectiveness of tibial periosteal flap pedicled with intermuscular branch of posterior tibial vessels combined with autologous bone graft in the treatment of tibial bone defects. Between January 2007 and December 2013, 19 cases of traumatic tibia bone and soft tissue defects were treated. There were 14 males and 5 females, aged from 18 to 49 years (mean, 28 years). The tibial fracture site located at the middle tibia in 6 cases and at the distal tibia in 13 cases. According to Gustilo type, 4 cases were rated as type III A, 14 cases as type III B, and 1 case as type III C (injury of anterior tibial artery). The length of bone defect ranged from 4.3 to 8.5 cm (mean, 6.3 cm). The soft tissue defects ranged from 8 cm x 5 cm to 17 cm x 9 cm. The time from injury to operation was 3 to 8 hours (mean, 4 hours). One-stage operation included debridement, external fixation, and vacuum sealing drainage. After formation of granulation tissue, the fresh wound was repaired with sural neurovascular flap or posterior tibial artery perforator flap. The flap size ranged from 10 cmx6 cm to 19 cm x 11 cm. In two-stage operation, tibial periosteal flap pedicled with intermuscular branch of posterior tibial vessels combined with autologous bone graft was used to repair tibial defect. The periosteal flap ranged from 6.5 cm x 4.0 cm to 9.0 cm x 5.0 cm; bone graft ranged from 4.5 to 9.0 cm in length. External fixation was changed to internal fixation. All flaps survived with soft texture, and no ulcer and infection occurred. All incisions healed by the first intention. All patients were followed up 18-40 months (mean, between normal and affected sides.The function of the knee an ankle joint was good without infection, malunion, and equinus. According to the Johner standard at last follow-up, the results were excellent in 15 cases, good in 3 cases, and fair in 1 case, with an excellent and good rate of 94.7%. Tibial periosteal flap pedicled with intermuscular branch of

  9. [Diagnosis of atrial septal defect using magnetic resonance imaging].

    Science.gov (United States)

    Sakakibara, M; Kobayashi, S; Imai, H; Watanabe, S; Masuda, Y; Inagaki, Y

    1987-12-01

    We studied the morphological features of defects of the interatrial septum using magnetic resonance imaging (MRI) to determine the sizes of defects and other abnormalities. MR images were obtained in 28 patients with atrial septal defect, including five cases with complicated anomalies (two with Ebstein's anomaly, one pentalogy of Fallot, and one anomalous pulmonary vein connection and azygos continuation). Images were also obtained in the control subjects including seven normal volunteers and 142 patients with various acquired heart diseases. The diagnosis of atrial septal defect was established by cardiac catheterization, angiography and two-dimensional echocardiography prior to the MRI studies, and in 14 patients, the diagnosis was confirmed by surgery. The MRI unit had a superconducting magnet and operated at 0.25 or 0.50 Tesla. A spin echo pulse sequence was used with an echo time of 40 or 60 msec. At the beginning of this study, non-gated MRI images were obtained in the 28 controls and in three patients with atrial septal defect. Nongated MRI could not image the anatomical structure of the interatrial septa of 12 of the 28 controls, or any of the three patients with atrial septal defect. Nongated MRI was, therefore, inadequate for visualizing cardiac anatomy. Gated MRI images were obtained in 141 controls and in 25 patients with atrial septal defect. Gated MRI revealed the interatrial septum, interventricular septum, atrioventricular septum, mitral valve, tricuspid valve and other intracardiac structures in most subjects. In 17 control subjects (12%), however, there was a very faint signal from the central portion of the interatrial septum. In these instances, there was a gradual fading of the signal of the interatrial septum, so that they could be distinguished from the atrial septal defect. The sudden disappearance of the signal from the interatrial septum was observed by gated MRI in all 25 patients with atrial septal defect. The sizes of the defects by

  10. Management of the Sequelae of Severe Congenital Abdominal Wall Defects

    Directory of Open Access Journals (Sweden)

    Sara Fuentes

    2016-05-01

    Full Text Available BackgroundThe survival rate of newborns with severe congenital abdominal wall defects has increased. After successfully addressing life-threatening complications, it is necessary to focus on the cosmetic and functional outcomes of the abdominal wall.MethodsWe performed a chart review of five cases treated in our institution.ResultsFive patients, ranging from seven to 18 years of age, underwent the following surgical approaches: simple approximation of the rectus abdominis fascia, the rectus abdominis sheath turnover flap, the placement of submuscular tissue expanders, mesh repair, or a combination of these techniques depending on the characteristics of each individual case.ConclusionsPatients with severe congenital abdominal wall defects require individualized surgical treatment to address both the aesthetic and functional issues related to the sequelae of their defects.

  11. Large animal in vivo evaluation of a binary blend polymer scaffold for skeletal tissue-engineering strategies; translational issues.

    Science.gov (United States)

    Smith, James O; Tayton, Edward R; Khan, Ferdous; Aarvold, Alexander; Cook, Richard B; Goodship, Allen; Bradley, Mark; Oreffo, Richard O C

    2017-04-01

    Binary blend polymers offer the opportunity to combine different desirable properties into a single scaffold, to enhance function within the field of tissue engineering. Previous in vitro and murine in vivo analysis identified a polymer blend of poly(l-lactic acid)-poly(ε-caprolactone) (PLLA:PCL 20:80) to have characteristics desirable for bone regeneration. Polymer scaffolds in combination with marrow-derived skeletal stem cells (SSCs) were implanted into mid-shaft ovine 3.5 cm tibial defects, and indices of bone regeneration were compared to groups implanted with scaffolds alone and with empty defects after 12 weeks, including micro-CT, mechanical testing and histological analysis. The critical nature of the defect was confirmed via all modalities. Both the scaffold and scaffold/SSC groups showed enhanced quantitative bone regeneration; however, this was only found to be significant in the scaffold/SSCs group (p = 0.04) and complete defect bridging was not achieved in any group. The mechanical strength was significantly less than that of contralateral control tibiae (p blend polymer scaffold. © 2015 The Authors. Journal of Tissue Engineering and Regenerative Medicine published by John Wiley & Sons, Ltd. © 2015 The Authors. Journal of Tissue Engineering and Regenerative Medicine published by John Wiley & Sons, Ltd.

  12. Reconstruction of sternal defect - a literature review

    DEFF Research Database (Denmark)

    Juhl, Alexander Andersen; Koudahl, Vibeke; Damsgaard, Tine Engberg

    2012-01-01

    OBJECTIVES: The management of sternal defects arisen after deep sternal wound infection is challenging and often requires extensive interdisciplinary teamwork between plastic and thoracic surgeons. In this study, the published literature on methods used to reconstruct sternal defects arisen...... as a result of deep sternal wound infection after open-heart surgery will be reviewed. DESIGN: The Cochrane, Embase, PubMed, and SveMed+ databases were searched in December 2011. Only papers regarding treatment of deep sternal wound infection after open-heart surgery in adults were included. RESULTS......: The literature search identified 224 original papers that met the inclusion criteria. The majority dealt with surgical techniques. None of the studies regarding reconstructive options were designed as randomized controlled trials, and the levels of evidence are generally low. CONCLUSION: The treatment of deep...

  13. Hyaluronic acid in calves defects correction

    Directory of Open Access Journals (Sweden)

    Lorenzo Rosset

    2014-09-01

    Full Text Available Aim: Since the advent of fillers, new techniques are continuously developed for different uses. In this study, we evaluated the use of hyaluronic acid for calf augmentation. Methods: A total of 42 patients were enrolled in this study. All of them underwent augmentation procedure in our centers under local anesthesia, the operations were completed within 1 h with a prompt correction of the defects. Results: Thirty-nine patients were satisfied with the treatment (93%, while three had complications, local infection, and lumps, that were resolved quickly (7%. Conclusion: Macrofillers can be injected into the calf to correct any defects. The advantages include short duration of treatment; the procedure performed under local anesthesia and limited side-effects that resolve promptly. This study suggests the use of biocompatible macrofillers for the augmentation of not only calves, but also for augmentation of breast and buttocks.

  14. Procurement strategies for combined multiorgan and composite tissues for transplantation.

    Science.gov (United States)

    Datta, Néha; Yersiz, Hasan; Kaldas, Fady; Azari, Kodi

    2015-04-01

    The purpose of this article is to identify the unique aspects of combined multiorgan and vascularized composite allograft (VCA) procurement from deceased donors and outline the steps essential for success. Transplantation of nonsolid organ composite tissues is becoming a viable option for reconstruction of massive tissue defects. With the United Network for Organ Sharing designation of VCAs as organs, placing them under the domain of the Organ Procurement and Transplantation Network, a systematic method for combined solid organ and VCA procurement is required. Several centers have reported experience with successful procurement strategies including sequential and simultaneous retrievals. The published literature describing donor screening, sequence of procurement with relation to solid organs and allocation is reviewed. With the 2013 classification of VCAs as organs, the Organ Procurement and Transplantation Network and United Network for Organ Sharing are better suited to aligning procurement and allocation policies. As VCA transplantation becomes more commonplace, protocol guidelines will ensure smooth integration with existing procurement infrastructure.

  15. Biomaterials mediated microRNA delivery for bone tissue engineering.

    Science.gov (United States)

    Sriram, M; Sainitya, R; Kalyanaraman, V; Dhivya, S; Selvamurugan, N

    2015-03-01

    Bone tissue engineering is an alternative strategy to overcome the problems associated with traditional treatments for bone defects. A number of bioactive materials along with new techniques like porous scaffold implantation, gene delivery, 3D organ printing are now-a-days emerging for traditional bone grafts and metal implants. Studying the molecular mechanisms through which these biomaterials induce osteogenesis is an equally hot field. Biomaterials could determine the fate of a cell via microRNAs (miRNAs). miRNAs are short non-coding RNAs that act as post-transcriptional regulators of gene expression and play an essential role for regulation of cell specific lineages including osteogenesis. Thus, this review focuses the recent trends on establishing a link of biomaterials with miRNAs and their delivery for bone tissue engineering applications. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Collective Calcium Signaling of Defective Multicellular Networks

    Science.gov (United States)

    Potter, Garrett; Sun, Bo

    2015-03-01

    A communicating multicellular network processes environmental cues into collective cellular dynamics. We have previously demonstrated that, when excited by extracellular ATP, fibroblast monolayers generate correlated calcium dynamics modulated by both the stimuli and gap junction communication between the cells. However, just as a well-connected neural network may be compromised by abnormal neurons, a tissue monolayer can also be defective with cancer cells, which typically have down regulated gap junctions. To understand the collective cellular dynamics in a defective multicellular network we have studied the calcium signaling of co-cultured breast cancer cells and fibroblast cells in various concentrations of ATP delivered through microfluidic devices. Our results demonstrate that cancer cells respond faster, generate singular spikes, and are more synchronous across all stimuli concentrations. Additionally, fibroblast cells exhibit persistent calcium oscillations that increase in regularity with greater stimuli. To interpret these results we quantitatively analyzed the immunostaining of purigenic receptors and gap junction channels. The results confirm our hypothesis that collective dynamics are mainly determined by the availability of gap junction communications.

  17. Introduction to tissue engineering applications and challenges

    CERN Document Server

    Birla, Ravi

    2014-01-01

    Covering a progressive medical field, Tissue Engineering describes the innovative process of regenerating human cells to restore or establish normal function in defective organs. As pioneering individuals look ahead to the possibility of generating entire organ systems, students may turn to this textbook for a comprehensive understanding and preparation for the future of regenerative medicine. This book explains chemical stimulations, the bioengineering of specific organs, and treatment plans for chronic diseases. It is a must-read for tissue engineering students and practitioners.

  18. Ultrasonic defect characterization using parametric-manifold mapping

    Science.gov (United States)

    Velichko, A.; Bai, L.; Drinkwater, B. W.

    2017-06-01

    The aim of ultrasonic non-destructive evaluation includes the detection and characterization of defects, and an understanding of the nature of defects is essential for the assessment of structural integrity in safety critical systems. In general, the defect characterization challenge involves an estimation of defect parameters from measured data. In this paper, we explore the extent to which defects can be characterized by their ultrasonic scattering behaviour. Given a number of ultrasonic measurements, we show that characterization information can be extracted by projecting the measurement onto a parametric manifold in principal component space. We show that this manifold represents the entirety of the characterization information available from far-field harmonic ultrasound. We seek to understand the nature of this information and hence provide definitive statements on the defect characterization performance that is, in principle, extractable from typical measurement scenarios. In experiments, the characterization problem of surface-breaking cracks and the more general problem of elliptical voids are studied, and a good agreement is achieved between the actual parameter values and the characterization results. The nature of the parametric manifold enables us to explain and quantify why some defects are relatively easy to characterize, whereas others are inherently challenging.

  19. Method of identifying defective particle coatings

    Science.gov (United States)

    Cohen, Mark E.; Whiting, Carlton D.

    1986-01-01

    A method for identifying coated particles having defective coatings desig to retain therewithin a build-up of gaseous materials including: (a) Pulling a vacuum on the particles; (b) Backfilling the particles at atmospheric pressure with a liquid capable of wetting the exterior surface of the coated particles, said liquid being a compound which includes an element having an atomic number higher than the highest atomic number of any element in the composition which forms the exterior surface of the particle coating; (c) Drying the particles; and (d) Radiographing the particles. By television monitoring, examination of the radiographs is substantially enhanced.

  20. Defects and diffusion, theory & simulation II

    CERN Document Server

    Fisher, David J

    2010-01-01

    This second volume in a new series covering entirely general results in the fields of defects and diffusion includes 356 abstracts of papers which appeared between the end of 2009 and the end of 2010. As well as the abstracts, the volume includes original papers on theory/simulation, semiconductors and metals: ""Predicting Diffusion Coefficients from First Principles ..."" (Mantina, Chen & Liu), ""Gouge Assessment for Pipes ..."" (Meliani, Pluvinage & Capelle), ""Simulation of the Impact Behaviour of ... Hollow Sphere Structures"" (Ferrano, Speich, Rimkus, Merkel & Öchsner), ""Elastic-Plastic

  1. Tissue depletion of taurine accelerates skeletal muscle senescence and leads to early death in mice.

    Science.gov (United States)

    Ito, Takashi; Yoshikawa, Natsumi; Inui, Takaaki; Miyazaki, Natsuko; Schaffer, Stephen W; Azuma, Junichi

    2014-01-01

    Taurine (2-aminoethanesulfonic acid) is found in milimolar concentrations in mammalian tissues. One of its main functions is osmoregulation; however, it also exhibits cytoprotective activity by diminishing injury caused by stress and disease. Taurine depletion is associated with several defects, many of which are found in the aging animal, suggesting that taurine might exert anti-aging actions. Therefore, in the present study, we examined the hypothesis that taurine depletion accelerates aging by reducing longevity and accelerating aging-associated tissue damage. Tissue taurine depletion in taurine transporter knockout (TauTKO) mouse was found to shorten lifespan and accelerate skeletal muscle histological and functional defects, including an increase in central nuclei containing myotubes, a reduction in mitochondrial complex 1 activity and an induction in an aging biomarker, Cyclin-dependent kinase 4 inhibitor A (p16INK4a). Tissue taurine depletion also enhances unfolded protein response (UPR), which may be associated with an improvement in protein folding by taurine. Our data reveal that tissue taurine depletion affects longevity and cellular senescence; an effect possibly linked to a disturbance in protein folding.

  2. Effects of mechanical loading on human mesenchymal stem cells for cartilage tissue engineering.

    Science.gov (United States)

    Choi, Jane Ru; Yong, Kar Wey; Choi, Jean Yu

    2018-03-01

    Today, articular cartilage damage is a major health problem, affecting people of all ages. The existing conventional articular cartilage repair techniques, such as autologous chondrocyte implantation (ACI), microfracture, and mosaicplasty, have many shortcomings which negatively affect their clinical outcomes. Therefore, it is essential to develop an alternative and efficient articular repair technique that can address those shortcomings. Cartilage tissue engineering, which aims to create a tissue-engineered cartilage derived from human mesenchymal stem cells (MSCs), shows great promise for improving articular cartilage defect therapy. However, the use of tissue-engineered cartilage for the clinical therapy of articular cartilage defect still remains challenging. Despite the importance of mechanical loading to create a functional cartilage has been well demonstrated, the specific type of mechanical loading and its optimal loading regime is still under investigation. This review summarizes the most recent advances in the effects of mechanical loading on human MSCs. First, the existing conventional articular repair techniques and their shortcomings are highlighted. The important parameters for the evaluation of the tissue-engineered cartilage, including chondrogenic and hypertrophic differentiation of human MSCs are briefly discussed. The influence of mechanical loading on human MSCs is subsequently reviewed and the possible mechanotransduction signaling is highlighted. The development of non-hypertrophic chondrogenesis in response to the changing mechanical microenvironment will aid in the establishment of a tissue-engineered cartilage for efficient articular cartilage repair. © 2017 Wiley Periodicals, Inc.

  3. Tissue depletion of taurine accelerates skeletal muscle senescence and leads to early death in mice.

    Directory of Open Access Journals (Sweden)

    Takashi Ito

    Full Text Available Taurine (2-aminoethanesulfonic acid is found in milimolar concentrations in mammalian tissues. One of its main functions is osmoregulation; however, it also exhibits cytoprotective activity by diminishing injury caused by stress and disease. Taurine depletion is associated with several defects, many of which are found in the aging animal, suggesting that taurine might exert anti-aging actions. Therefore, in the present study, we examined the hypothesis that taurine depletion accelerates aging by reducing longevity and accelerating aging-associated tissue damage. Tissue taurine depletion in taurine transporter knockout (TauTKO mouse was found to shorten lifespan and accelerate skeletal muscle histological and functional defects, including an increase in central nuclei containing myotubes, a reduction in mitochondrial complex 1 activity and an induction in an aging biomarker, Cyclin-dependent kinase 4 inhibitor A (p16INK4a. Tissue taurine depletion also enhances unfolded protein response (UPR, which may be associated with an improvement in protein folding by taurine. Our data reveal that tissue taurine depletion affects longevity and cellular senescence; an effect possibly linked to a disturbance in protein folding.

  4. Recent Developments of Functional Scaffolds for Craniomaxillofacial Bone Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Yukihiko Kinoshita

    2013-01-01

    Full Text Available Autogenous bone grafting remains a gold standard for the reconstruction critical-sized bone defects in the craniomaxillofacial region. Nevertheless, this graft procedure has several disadvantages such as restricted availability, donor-site morbidity, and limitations in regard to fully restoring the complicated three-dimensional structures in the craniomaxillofacial bone. The ultimate goal of craniomaxillofacial bone reconstruction is the regeneration of the physiological bone that simultaneously fulfills both morphological and functional restorations. Developments of tissue engineering in the last two decades have brought such a goal closer to reality. In bone tissue engineering, the scaffolds are fundamental, elemental and mesenchymal stem cells/osteoprogenitor cells and bioactive factors. A variety of scaffolds have been developed and used as spacemakers, biodegradable bone substitutes for transplanting to the new bone, matrices of drug delivery system, or supporting structures enhancing adhesion, proliferation, and matrix production of seeded cells according to the circumstances of the bone defects. However, scaffolds to be clinically completely satisfied have not been developed yet. Development of more functional scaffolds is required to be applied widely to cranio-maxillofacial bone defects. This paper reviews recent trends of scaffolds for crania-maxillofacial bone tissue engineering, including our studies.

  5. Correlation of cutaneous tension distribution and tissue oxygenation with acute external tissue expansion

    Directory of Open Access Journals (Sweden)

    Marquardt C

    2009-11-01

    Full Text Available Abstract Today, the biomechanical fundamentals of skin expansion are based on viscoelastic models of the skin. Although many studies have been conducted in vitro, analyses performed in vivo are rare. Here, we present in vivo measurements of the expansion at the skin surface as well as measurement of the corresponding intracutaneous oxygen partial pressure. In our study the average skin stretching was 24%, with a standard deviation of 11%, excluding age or gender dependency. The measurement of intracutaneous oxygen partial pressure produced strong inter-individual fluctuations, including initial values at the beginning of the measurement, as well as varying individual patient reactions to expansion of the skin. Taken together, we propose that even large defect wounds can be closed successfully using the mass displacement caused by expansion especially in areas where soft, voluminous tissue layers are present.

  6. Periodontal Defects in the A116T Knock-in Murine Model of Odontohypophosphatasia.

    Science.gov (United States)

    Foster, B L; Sheen, C R; Hatch, N E; Liu, J; Cory, E; Narisawa, S; Kiffer-Moreira, T; Sah, R L; Whyte, M P; Somerman, M J; Millán, J L

    2015-05-01

    Mutations in ALPL result in hypophosphatasia (HPP), a disease causing defective skeletal mineralization. ALPL encodes tissue nonspecific alkaline phosphatase (ALP), an enzyme that promotes mineralization by reducing inorganic pyrophosphate, a mineralization inhibitor. In addition to skeletal defects, HPP causes dental defects, and a mild clinical form of HPP, odontohypophosphatasia, features only a dental phenotype. The Alpl knockout (Alpl (-/-)) mouse phenocopies severe infantile HPP, including profound skeletal and dental defects. However, the severity of disease in Alpl (-/-) mice prevents analysis at advanced ages, including studies to target rescue of dental tissues. We aimed to generate a knock-in mouse model of odontohypophosphatasia with a primarily dental phenotype, based on a mutation (c.346G>A) identified in a human kindred with autosomal dominant odontohypophosphatasia. Biochemical, skeletal, and dental analyses were performed on the resulting Alpl(+/A116T) mice to validate this model. Alpl(+/A116T) mice featured 50% reduction in plasma ALP activity compared with wild-type controls. No differences in litter size, survival, or body weight were observed in Alpl(+/A116T) versus wild-type mice. The postcranial skeleton of Alpl(+/A116T) mice was normal by radiography, with no differences in femur length, cortical/trabecular structure or mineral density, or mechanical properties. Parietal bone trabecular compartment was mildly altered. Alpl(+/A116T) mice featured alterations in the alveolar bone, including radiolucencies and resorptive lesions, osteoid accumulation on the alveolar bone crest, and significant differences in several bone properties measured by micro-computed tomography. Nonsignificant changes in acellular cementum did not appear to affect periodontal attachment or function, although circulating ALP activity was correlated significantly with incisor cementum thickness. The Alpl(+/A116T) mouse is the first model of odontohypophosphatasia

  7. Reconstruction of Ligament and Tendon Defects Using Cell Technologies.

    Science.gov (United States)

    Chailakhyan, R K; Shekhter, A B; Ivannikov, S V; Tel'pukhov, V I; Suslin, D S; Gerasimov, Yu V; Tonenkov, A M; Grosheva, A G; Panyushkin, P V; Moskvina, I L; Vorob'eva, N N; Bagratashvili, V N

    2017-02-01

    We studied the possibility of restoring the integrity of the Achilles tendon in rabbits using autologous multipotent stromal cells. Collagen or gelatin sponges populated with cells were placed in a resorbable Vicryl mesh tube and this tissue-engineered construct was introduced into a defect of the middle part of the Achilles tendon. In 4 months, histological analysis showed complete regeneration of the tendon with the formation of parallel collagen fibers, spindle-shaped tenocytes, and newly formed vessels.

  8. Determination of defect content and defect profile in semiconductor heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Zubiaga, A [Laboratory of Physics, HUT, PO Box 1100, 02015 TKK, Espoo (Finland); Garcia, J A; Plazaola, F [Zientzia eta Teknologia Fakultatea, Euskal Herriko Unbertsitatea, P. K. 644, 48080, Bilbao (Spain); Zuniga-Perez, J; Munoz-Sanjose, V, E-mail: fernando.plazaola@ehu.es [Universitat de Valencia, Departamento de Fisica Aplicada i Electromagnetisme, Dr. Moliner 50, 46100 Burjassot, Valencia (Spain)

    2011-01-10

    In this article we present an overview of the technique to obtain the defects depth profile and width of a deposited layer and multilayer based on positron annihilation spectroscopy. In particular we apply the method to ZnO and ZnO/ZnCdO layers deposited on sapphire substrates. After introducing some terminology we first calculate the trend that the W/S parameters of the Doppler broadening measurements must follow, both in a qualitative and quantitative way. From this point we extend the results to calculate the width and defect profiles in deposited layer samples.

  9. Tissue Classification

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, David Gerald [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    The project began as a e ort to support InLight and Lumidigm. With the sale of the companies to a non-New Mexico entity, the project then focused on supporting a new company Medici Technologies. The Small Business (SB) is attempting to quantify glucose in tissue using a series of short interferometer scans of the nger. Each scan is produced from a novel presentation of the nger to the device. The intent of the project is to identify and, if possible, implement improved methods for classi cation, feature selection, and training to improve the performance of predictive algorithms used for tissue classi cation.

  10. Stoichiometric Defects in Silicon Carbide

    International Nuclear Information System (INIS)

    Liao, Ting; Bedoya-Martinez, O. N.; Roma, G.; Liao, Ting; Liao, Ting

    2010-01-01

    Defect structures showing odd-membered rings are known features of several tetrahedral semiconductors as well as carbon nano-structures; examples of them are bond defects in crystalline and amorphous silicon, Stone Wales defects in fullerenes and carbon nano-tubes, and the core structure of partial dislocations in some tetrahedral semiconductors. We investigate, using Density Functional Theory, two types of stoichiometry-conserving defects, which we call SCD and anti-SCD and which are metastable structures presenting five- and seven-membered rings, both in the cubic and in the hexagonal 4H-SiC polytypes. We also investigate the annealing properties of the two mentioned variants and find that one of them (SCD) easily disappears, turning back to a normal site, while the other (anti-SCD) transforms to an antisite pair, overcoming a barrier of 0. 21 eV. The very short lifetimes at ambient conditions explain why those defects have not been observed up to now, but they suggest they should be observable at very low temperature, and we provide local vibrational modes to facilitate their identification. (authors)

  11. Closure of round cutaneous defects progressively with the purse string suture technique.

    Science.gov (United States)

    Küçükdurmaz, Fatih; Agir, Ismail; Gümüstas, Seyitali; Kivilcim, Hakan; Tetik, Cihangir

    2015-01-01

    There are many closure techniques available to cutaneous surgeons. One of them is the purse-string suture which is used to provide complete or partial closure of round skin defects. In our animal study; we closed skin defects with using subcuticular purse string suture technique by progressively cinching wound and we aim to more rapidly healing according to secondary healing. After anaesthetize, we created a 4 cm diameter circular full thickness skin defect on dorsal area of rats. In group 1, subcuticular purse string suture was applied by using a nonabsorbable and monofilament suture and a sliding arthroscopic knot was applied to both ends. Arthroscopic suture was shift 1 cm forward every day. In group 2 skin defect was leaved open and daily dressing was made and in both group defect diameters were measured every day and noted. The skin defects were closed totally after 15 days in group 1 but in group 2 defects were reduced but still had a mean 1,5-cm diameter sircular defect. Closing large circular wound with purse string suture and gradual tightening decreases the healing time and expand the skin tissue without using any tissue expander.

  12. Genetic epidemiology of neural tube defects.

    Science.gov (United States)

    Lupo, Philip J; Agopian, A J; Castillo, Heidi; Castillo, Jonathan; Clayton, Gerald H; Dosa, Nienke P; Hopson, Betsy; Joseph, David B; Rocque, Brandon G; Walker, William O; Wiener, John S; Mitchell, Laura E

    2017-12-11

    It has been estimated that 60-70% of neural tube defects (NTDs) have a genetic component, but few causative genes have been identified. The lack of information on genes associated with non-syndromic NTDs in humans is especially notable as the "genomic revolution" has led to new tools (e.g., genome-wide genotyping arrays, next-generation sequencing) that are helping to elucidate the full spectrum of genetic variation (from common to rare) contributing to complex traits, including structural birth defects. However, the application of modern genomic approaches to the study of NTDs has lagged behind that of some other common structural birth defects. This may be due to the difficulty of assembling large study cohorts for anencephaly or spina bifida. The purpose of this review is to outline the evolution of genetic studies of NTDs, from studies of familial aggregation to candidate gene and genome-wide association studies, through whole-exome and whole-genome sequencing. Strategies for addressing gaps in NTD genetic research are also explored.

  13. Automatically high accurate and efficient photomask defects management solution for advanced lithography manufacture

    Science.gov (United States)

    Zhu, Jun; Chen, Lijun; Ma, Lantao; Li, Dejian; Jiang, Wei; Pan, Lihong; Shen, Huiting; Jia, Hongmin; Hsiang, Chingyun; Cheng, Guojie; Ling, Li; Chen, Shijie; Wang, Jun; Liao, Wenkui; Zhang, Gary

    2014-04-01

    Defect review is a time consuming job. Human error makes result inconsistent. The defects located on don't care area would not hurt the yield and no need to review them such as defects on dark area. However, critical area defects can impact yield dramatically and need more attention to review them such as defects on clear area. With decrease in integrated circuit dimensions, mask defects are always thousands detected during inspection even more. Traditional manual or simple classification approaches are unable to meet efficient and accuracy requirement. This paper focuses on automatic defect management and classification solution using image output of Lasertec inspection equipment and Anchor pattern centric image process technology. The number of mask defect found during an inspection is always in the range of thousands or even more. This system can handle large number defects with quick and accurate defect classification result. Our experiment includes Die to Die and Single Die modes. The classification accuracy can reach 87.4% and 93.3%. No critical or printable defects are missing in our test cases. The missing classification defects are 0.25% and 0.24% in Die to Die mode and Single Die mode. This kind of missing rate is encouraging and acceptable to apply on production line. The result can be output and reloaded back to inspection machine to have further review. This step helps users to validate some unsure defects with clear and magnification images when captured images can't provide enough information to make judgment. This system effectively reduces expensive inline defect review time. As a fully inline automated defect management solution, the system could be compatible with current inspection approach and integrated with optical simulation even scoring function and guide wafer level defect inspection.

  14. Reconstruction of a midfacial defect using an intraoral-extraoral combination prosthesis employing magnets: a clinical report

    OpenAIRE

    Nair, Anoop; Regish, K M.; Shah, Farhan K.; Prithviraj, D R.

    2012-01-01

    Radical maxillectomy frequently leads to extended defects in hard and soft tissues that result in a connection between the oral cavities and orbit. If the defect cannot be surgically reconstructed, a combination prosthesis may be necessary to remedy dysfunction in patient function, comfort, esthetics. For minor defects, enlargement of the base of the intra oral prosthesis is generally sufficient. Resections that affect more than one third of the maxilla usually require an intra oral and an ex...

  15. Enamel Defects of Human Primary Dentition as Virtual Memory of Early Developmental Events

    Directory of Open Access Journals (Sweden)

    Naser Asl Aminabadi

    2009-12-01

    Full Text Available Background and aims. The objectives of the present study were to investigate the prevalence and the position of enamel defects of primary teeth and hence to estimate the approximate time of an insult. Material and methods. 121 children aged 3 to 5 years were included in the study. The Modified Developmental Defects of Enamel Index was used to diagnose and classify the defects. The defects were categorized as hypoplasia, hypocalcification or a combination of them. Each tooth was investigated for occlusal/incisal, middle, cervical, incisomiddle, cervicomiddle and complete crown defects. Results. 55.37% of the children were affected by enamel defects, 23.96% being categorized as hypocalcification and 22.31% as hypoplasia. The enamel defects were more abundant in maxillary primary incisors and mandibular primary canines. Minimum involvement was seen in maxillary primary second molars and mandibular primary lateral incisors. The prevalence of cervical defects in maxillary primary incisors was significantly more than the middle or incisal defects (P < 0.05. The prevalence of incisal defects in mandibular primary incisors was significantly more than the middle or cervical defects (P < 0.05. Conclusions. The results revealed a considerable number of enamel defects which are multiple, symmetric and chronologically accordant with the estimated neonatal line in primary teeth of healthy children.

  16. Freely-migrating defects: Their production and interaction with cascade remnants

    International Nuclear Information System (INIS)

    Rehn, L.E.; Wiedersich, H.

    1991-05-01

    Many microstructural changes that occur during irradiation are driven primarily by freely-migrating defects, i.e. those defects which escape from nascent cascades to migrate over distances that are large relative to typical cascade dimensions. Several measurements during irradiation at elevated temperatures have shown that the survival rate of freely-migrating defects decreases much more strongly with increasing primary recoil energy than does the survival rate for defects generated at liquid helium temperatures. For typical fission or fusion recoil spectra, and for heavy-ion bombardment, the fraction of defects that migrate long-distances is apparently only ∼1% of the calculated dpa. This small surviving fraction of freely-migrating defects results at least partially from additional intracascade recombination at elevated temperatures. However, cascade remnants, e.g., vacancy and interstitial clusters, also contribute by enhancing intercascade defect annihilation. A recently developed rate-theory approach is used to discuss the relative importance of intra- and intercascade recombination to the survival rate of freely-migrating defects. Within the validity of certain simplifying assumptions, the additional sink density provided by defect clusters produced directly within individual cascades can explain the difference between a defect survival rate of about 30% for low dose, low temperature irradiations with heavy ions, and a survival rate of only ∼1% for freely-migrating defects at elevated temperatures. The status of our current understanding of freely-migrating defects, including remaining unanswered questions, is also discussed. 33 refs., 5 figs

  17. Enhancing native defect sensitivity for EUV actinic blank inspection: optimized pupil engineering and photon noise study

    Science.gov (United States)

    Wang, Yow-Gwo; Neureuther, Andrew; Naulleau, Patrick

    2016-03-01

    In this paper, we discuss the impact of optimized pupil engineering and photon noise on native defect sensitivity in EUV actinic blank inspection. Native defects include phase-dominated defects, absorber defects, and defects with a combination of phase and absorption behavior. First, we extend the idea of the Zernike phase contrast (ZPC) method and study the impact of optimum phase shift in the pupil plane on native defect sensitivity, showing a 23% signal-to-noise ratio (SNR) enhancement compare to bright field (BF) for a phase defect with 20% absorption. We also describe the possibility to increase target defect SNR on target defect sizes at the price of losing the sensitivity on smaller (non-critical) defects. Moreover, we show the advantage of the optimized phase contrast (OZPC) method over BF EUV actinic blank inspection. A single focus scan from OZPC has better inspection efficiency over BF. Second, we make a detailed comparison between the phase contrast with apodization (AZPC) method and dark field (DF) method based on defect sensitivity in the presence of both photon shot noise and camera noise. Performance is compared for a variety of photon levels, mask roughness conditions, and combinations of defect phase and absorption.

  18. Defect CFTs and holographic multiverse

    Energy Technology Data Exchange (ETDEWEB)

    Fiol, Bartomeu, E-mail: bfiol@ub.edu [Departament de Física Fonamental i Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, 08193 Barcelona (Spain)

    2010-07-01

    We investigate some aspects of a recent proposal for a holographic description of the multiverse. Specifically, we focus on the implications on the suggested duality of the fluctuations of a bubble separating two universes with different cosmological constants. We do so by considering a similar problem in a 2+1 CFT with a codimension one defect, obtained by an M5-brane probe embedding in AdS{sub 4} × S{sup 7}, and studying its spectrum of fluctuations. Our results suggest that the kind of behavior required by the spectrum of bubble fluctuations is not likely to take place in defect CFTs with an AdS dual, although it might be possible if the defect supports a non-unitary theory.

  19. Therapeutic efficacy of guided tissue regeneration and connective tissue autotransplants with periosteum in the management of gingival recession

    Directory of Open Access Journals (Sweden)

    Jovičić Bojan

    2008-01-01

    Full Text Available Background/Aim. Gingival recession progression in clinical practice as an ethiological factor of periodontal diseases, and symptoms of the disease have caused the development of various surgical procedures and techniques of the reconstruction of periodontal defects. The aim of this study was to verify efficacy of surgical procedures that include connective tissue autotransplants with periosteum and guided tissue regeneration for the treatment of gingival recession. Methods. The study included 20 teet with gingival recession, Müller class II and III. Ten teeth with gingival recession were treated with resorptive membrane and coronary guided surgical flap (GTR group. On the contralateral side 10 teeth with gingival recession were treated with connective tissue autotransplants with periosteum in combination with coronary guided surgical flap (TVT group. We measured the degree of epithelial attachment (DEA, width of subgingival curettage (WGC and vertical deepness of recession (VDR. For statistical significance we used Student's ttest. Results. The study revealed statistical significance in reducing VDR by both used treatments. Root deepness in GTR and TVT group was 63.5%, and 90%, respectively. With both surgical techniques we achieved coronary dislocation of the epithelial attachment, larger zone of gingival curettage, and better oral hygiene. Conclusion. Current surgical techniques are effective in the regeneration of deep periodontal spaces and the treatment of gingival recession. Significantly better results were achieved with the used coronary guided surgical flap than with guided tissue regeneration.

  20. A review of fibrin and fibrin composites for bone tissue engineering.

    Science.gov (United States)

    Noori, Alireza; Ashrafi, Seyed Jamal; Vaez-Ghaemi, Roza; Hatamian-Zaremi, Ashraf; Webster, Thomas J

    2017-01-01

    Tissue engineering has emerged as a new treatment approach for bone repair and regeneration seeking to address limitations associated with current therapies, such as autologous bone grafting. While many bone tissue engineering approaches have traditionally focused on synthetic materials (such as polymers or hydrogels), there has been a lot of excitement surrounding the use of natural materials due to their biologically inspired properties. Fibrin is a natural scaffold formed following tissue injury that initiates hemostasis and provides the initial matrix useful for cell adhesion, migration, proliferation, and differentiation. Fibrin has captured the interest of bone tissue engineers due to its excellent biocompatibility, controllable biodegradability, and ability to deliver cells and biomolecules. Fibrin is particularly appealing because its precursors, fibrinogen, and thrombin, which can be derived from the patient's own blood, enable the fabrication of completely autologous scaffolds. In this article, we highlight the unique properties of fibrin as a scaffolding material to treat bone defects. Moreover, we emphasize its role in bone tissue engineering nanocomposites where approaches further emulate the natural nanostructured features of bone when using fibrin and other nanomaterials. We also review the preparation methods of fibrin glue and then discuss a wide range of fibrin applications in bone tissue engineering. These include the delivery of cells and/or biomolecules to a defect site, distributing cells, and/or growth factors throughout other pre-formed scaffolds and enhancing the physical as well as biological properties of other biomaterials. Thoughts on the future direction of fibrin research for bone tissue engineering are also presented. In the future, the development of fibrin precursors as recombinant proteins will solve problems associated with using multiple or single-donor fibrin glue, and the combination of nanomaterials that allow for the

  1. The impact of thickness of resorbable membrane of human origin on the ossification of bone defects: A pathohistologic study

    Directory of Open Access Journals (Sweden)

    Bubalo Marija

    2012-01-01

    Full Text Available Background/Aim. A wide range of resorbable and nonresorbable membranes have been investigated over the last two decades. The barrier membrane protects the defect from ingrowth of soft tissue cells and allows bone progenitor cells to develop bone within a blood clot that is formed beneath the barrier membrane. The membranes are applied to reconstruct small bony defect prior to implantation, to cover dehiscences and fenestrations around dental implants. The aim of this study was to evaluate the influence of human resorbable demineralized membrane (RHDM thickness on bone regeneration. Methods. The experiment, approved by Ethical Committee, was performed on 6 dogs and conducted into three phases. Bone defects were created in all the 6 dogs on the left side of the mandible, 8 weeks after extraction of second, third and fourth premolars. One defect was covered with RHDM 100 μ thick, one with RHDM 200 μ thick, and the third defect left empty (control defect. The histopathological analysis was done 2, 4 and 6 months after the surgery. In the third phase samples of bone tissue were taken and subjected to histopathological analysis. Results. In all the 6 dogs the defects treated with RHDM 200 μ thick showed higher level of bone regeneration in comparison with the defect treated with RHDM 100 μ thick and especially with empty defect. Conclusion. Our results demonstrated that the thicker membrane showed the least soft tissue ingrowths and promoted better bone formation at 6 months compared with a thinner one.

  2. Two-dimensional transition metal dichalcogenides: interface and defect engineering.

    Science.gov (United States)

    Hu, Zehua; Wu, Zhangting; Han, Cheng; He, Jun; Ni, Zhenhua; Chen, Wei

    2018-03-06

    Two-dimensional (2D) transition metal dichalcogenides (TMDCs) have been considered as promising candidates for next generation nanoelectronics. Because of their atomically-thin structure and high surface to volume ratio, the interfaces involved in TMDC-based devices play a predominant role in determining the device performance, such as charge injection/collection at the metal/TMDC interface, and charge carrier trapping at the dielectric/TMDC interface. On the other hand, the crystalline structures of TMDCs are enriched by a variety of intrinsic defects, including vacancies, adatoms, grain boundaries, and substitutional impurities. Customized design and engineering of the interfaces and defects provides an effective way to modulate the properties of TMDCs and finally enhance the device performance. Herein, we summarize and highlight recent advances and state-of-the-art investigations on the interface and defect engineering of TMDCs and their corresponding applications in electronic and optoelectronic devices. Various interface engineering approaches for TMDCs are overviewed, including surface charge transfer doping, TMDC/metal contact engineering, and TMDC/dielectric interface engineering. Subsequently, different types of structural defects in TMDCs are introduced. Defect engineering strategies utilized to modulate the optical and electronic properties of TMDCs, as well as the developed high-performance and functional devices are summarized. Finally, we highlight the challenges and opportunities for interface and defect engineering in TMDC materials for electronics and optoelectronics.

  3. Catalysts for better health care. Medical tissue banks bring multiple benefits to countries

    International Nuclear Information System (INIS)

    Phillips, G.O.; Morales, J.

    2002-01-01

    For millions of injured and disabled people around the world, the treatment brings a new quality of life. Called tissue grafting or transplantation, it relies on the use of sterilized bone, skin, and other tissues to heal serious injuries, wounds, and sickness. Prime beneficiaries include severe burn victims, and men, women, and children suffering from crippling diseases, birth defects, and blindness. Long applied in plastic and orthopaedic surgery, tissue grafting once relied only on using a patient's own tissues, known as an autograft. But now tissues from human or animal donors (allograft) are used for transplantation. This new form of tissue grafting has made big strides over the past decade. An expanding number of facilities today prepare the valuable tissues to the high-quality standards demanded in medical care. Dozens of such new tissue banks have opened in Asia, Latin America, Europe, and North America. A productive channel of progress has been an IAEA-supported technical cooperation programme. Through it, experts have worked together behind the scenes to help national health authorities establish tissue banks, train associated staff, and develop standards and regulatory guides. The IAEA accordingly has gained more experience and success than any other international organization in supporting the establishment of tissue banks for medical use in developing countries. Increasingly for quality and cost reasons, the technology of irradiation is used to sterilize tissues for medical care. The IAEA, through its technical cooperation channels, assists national atomic energy authorities to safely and productively employ radiation technology. An interregional programme on radiation and tissue banking, initiated over a decade ago, today extends to 30 countries

  4. Tenonplasty for closing defects during sclerocorneal surgery-A brief review of its anatomy and clinical applications.

    Science.gov (United States)

    Fries, Fabian N; Suffo, Shady; Daas, Loay; Seitz, Berthold; Fiorentzis, Miltiadis; Viestenz, Arne

    2018-01-01

    To provide insight into the clinical anatomy of Tenon's capsule and to describe a technique to manage sclerocorneal defects using autologous Tenon's tissue. A thin layer of Tenon's capsule harvested from the patient's own eye is used to seal the defect and act as a scaffold. The Tenon's flap is spread over the defect and held in place by Vicryl sutures. A bandage contact lens is then placed on the eye. Tenon's capsule is composed of thick fibrous tissue with smooth muscle fibers and a thin posterior capsule of orbital fat. It is rich in fibroblasts, which can accelerate wound healing and eventually lead to robust scarring without risk of immunogenicity and without cost. Tenonplasty uses easily-available autologous Tenon's tissue in patients with sclerocorneal defects to preserve globe morphology. The technique is a feasible alternative not limited by the availability of graft tissue. Clin. Anat. 31:72-76, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  5. Satellite spot defect reduction on 193-nm contact hole lithography using photo cell monitor methodology

    Science.gov (United States)

    Boulenger, Caroline; Caze, Jean-Luc; Mihet, Mihaela

    2006-03-01

    The goal of overall process and yield improvement requires a litho defect management and reduction strategy, which includes several layers of tactical methods. Defects may be identified through a number of schemes, including After-Develop Inspection (ADI), which was the primary tool in this study in our 0,13μ fab. Defects on 193nm contact hole lithography were identified using a KLA-Tencor 2351 High Resolution Imaging Patterned Wafer Inspection System, coupled with in-line Automatic Defect Classification (iADC). The optimized inspection was used at the core of the Photo Cell Monitor (PCM) to isolate critical defect types. PCM uses the fab's standard production resist coat, exposure, develop, and rinse process, with the focus and exposure optimized for resist on silicon test wafers. Through Pareto analysis of 193nm defects, one defect type, called satellite spot, was targeted for immediate improvement and monitoring. This paper describes the work done in improving the litho defectivity. The work includes optimization of inspection and classification parameters and the Design of Experiments (DOE) to identify the source (including the interaction between the resist and developer) and contributing factors. Several process modifications were identified which resulted in lowered defectivity up to complete suppression of satellite spot defects, although at higher process complexity and cost. This work was also done in conjunction with resist suppliers, which used the same inspection to confirm the problem at their facilities. The work with the suppliers continues with the goal of identifying a less expensive permanent solution.

  6. Periodontal regeneration - intrabony defects: a consensus report from the AAP Regeneration Workshop.

    Science.gov (United States)

    Reynolds, Mark A; Kao, Richard T; Camargo, Paulo M; Caton, Jack G; Clem, Donald S; Fiorellini, Joseph P; Geisinger, Maria L; Mills, Michael P; Nares, Salvador; Nevins, Marc L

    2015-02-01

    Treatment of intrabony defects is an important therapeutic goal of periodontal therapy. The goal of this consensus report was to critically appraise the evidence for the available approaches for promoting periodontal regeneration in intrabony defects. In addition to evaluating the effectiveness of new regenerative approaches for intrabony defects, recommendations for future research were defined for this area. A systematic review was conducted using computerized searches of PubMed and Cochrane databases, supplemented with screening of references in original reports, review articles, and a hand search in selected journals. All searches were focused on regenerative approaches with histologic evidence of periodontal regeneration (proof of principle), clinical trials, and case reports. For purposes of analysis, change in intrabony defect fill was considered the primary outcome variable, with change in clinical attachment as a secondary outcome. The SORT (Strength of Recommendation Taxonomy) grade was used to evaluate the quality and strength of the evidence. During the consensus meeting, the group agreed on the outcomes of the systematic review, pertinent sources of evidence, clinical recommendations, and areas requiring future research. The systematic review, which was conducted for the consensus conference, evaluated the effectiveness of the use of biologics for the treatment of intrabony defects. Enamel matrix derivative (EMD) and recombinant human platelet-derived growth factor-BB (rhPDGF-BB) with β-tricalcium phosphate were shown to be efficacious in regenerating intrabony defects. The level of evidence is supported by multiple studies documenting effectiveness. The clinical application of biologics supports improvements in clinical parameters comparable with selected bone replacement grafts and guided tissue regeneration (GTR). Factors negatively affecting regeneration included smoking and excessive tooth mobility. Periodontal regeneration in intrabony defects

  7. Restoration of long bone defects treated with the induced membrane technique: protocol and outcomes.

    Science.gov (United States)

    Giannoudis, Peter V; Harwood, Paul J; Tosounidis, Theodoros; Kanakaris, Nikolaos K

    2016-12-01

    This prospective study was undertaken at a regional tertiary referral centre to evaluate the results of treatment of bone defects managed with the induced membrane (IM) technique. Inclusion criteria were patients with bone defects secondary to septic non-union, chronic osteomyelitis and acute fracture with bone loss. Pathological fractures with bone loss were excluded. Data collection included patient demographics, pathology, previous surgical intervention, size of bone defect, type of graft implanted, time-to-union and complications/reinterventions. The minimum time of follow up was 12 months. Forty-three patients (32 males) met the inclusion criteria with a mean age of 47.9 years (range 18-80 years). 22 patients had an acute traumatic bone loss associated with open fracture and 21 presented with an infected non-union or underlying osteomyelitis requiring bone excision. The most common microorganisms grown were staphylcoccous aureus and coagulase negative staphylococcous. The mean length of the bone defect area was 4.2 cm (range 2-12 cm). All patients were managed with the two stage technique receiving composited grafting (Autologous bone graft (Iliac crest/RIA), graft expander as required, osteoprogenitor cells, growth factor) during the second stage. There was one failure (humeral infected non-union) in a previous background of bone radiation that necessitated reconstruction with a free fibula vascularized graft. One patient had a fall and sustained implant failure (humeral defect) 3 months after reconstruction and following re-plating progressed to union 4 months later. Two patients required re-grafting due to failure of healing in one of the defect sides. One patient presented with a discharging sinus 2 years after successful healing of a tibial defect that was treated successfully with soft tissue and bone debridement without necessitating further interventions. One patient despite union (distal 1/3 tibia) underwent a below knee amputation due to a

  8. Gene expression profile of the cartilage tissue spontaneously regenerated in vivo by using a novel double-network gel: Comparisons with the normal articular cartilage

    Directory of Open Access Journals (Sweden)

    Kurokawa Takayuki

    2011-09-01

    Full Text Available Abstract Background We have recently found a phenomenon that spontaneous regeneration of a hyaline cartilage-like tissue can be induced in a large osteochondral defect by implanting a double-network (DN hydrogel plug, which was composed of poly-(2-Acrylamido-2-methylpropanesulfonic acid and poly-(N, N'-Dimetyl acrylamide, at the bottom of the defect. The purpose of this study was to clarify gene expression profile of the regenerated tissue in comparison with that of the normal articular cartilage. Methods We created a cylindrical osteochondral defect in the rabbit femoral grooves. Then, we implanted the DN gel plug at the bottom of the defect. At 2 and 4 weeks after surgery, the regenerated tissue was analyzed using DNA microarray and immunohistochemical examinations. Results The gene expression profiles of the regenerated tissues were macroscopically similar to the normal cartilage, but showed some minor differences. The expression degree of COL2A1, COL1A2, COL10A1, DCN, FMOD, SPARC, FLOD2, CHAD, CTGF, and COMP genes was greater in the regenerated tissue than in the normal cartilage. The top 30 genes that expressed 5 times or more in the regenerated tissue as compared with the normal cartilage included type-2 collagen, type-10 collagen, FN, vimentin, COMP, EF1alpha, TFCP2, and GAPDH genes. Conclusions The tissue regenerated by using the DN gel was genetically similar but not completely identical to articular cartilage. The genetic data shown in this study are useful for future studies to identify specific genes involved in spontaneous cartilage regeneration.

  9. Soft Tissue Reconstruction following Hemipelvectomy: Eight-Year Experience and Literature Review

    Directory of Open Access Journals (Sweden)

    A. Z. Mat Saad

    2012-01-01

    Results. Thirteen patients were included with median age of 39 years (range 13–78 of which all had advanced tumour with stage IIb (54% and Stage III (46%. External hemipelvectomy was performed in all cases, and resultant defects were reconstructed with variety type of flaps. These include fillet thigh flaps, regional pedicle flaps of different designs, and free flap. Conclusions. Massive pelvic tumour is rarely encountered in our population but can be seen across all age groups and usually due to late presentation. The defects should be reconstructed using local or regional flaps, incorporating the muscle component to enhance flap perfusion. The tissue should be harvested from the amputated limb, as it can limit the donor site morbidity.

  10. Defect branes as Alice strings

    International Nuclear Information System (INIS)

    Okada, Takashi; Sakatani, Yuho

    2015-01-01

    There exist various defect-brane backgrounds in supergravity theories which arise as the low energy limit of string theories. These backgrounds typically have non-trivial monodromies, and if we move a charged probe around the center of a defect, its charge will be changed by the action of the monodromy. During the process, the charge conservation law seems to be violated. In this paper, to resolve this puzzle, we examine a dynamics of the charge changing process and show that the missing charge of the probe is transferred to the background. We then explicitly construct the resultant background after the charge transfer process by utilizing dualities. This background has the same monodromy as the original defect brane, but has an additional charge which does not have any localized source. In the literature, such a charge without localized source is known to appear in the presence of Alice strings. We argue that defect branes can in fact be regarded as a realization of Alice strings in string theory and examine the charge transfer process from that perspective.

  11. Space Mapping and Defect Correction

    NARCIS (Netherlands)

    D. Echeverria (David); D.J.P. Lahaye (Domenico); P.W. Hemker (Piet); W.H.A. Schilders (Wil); H.A. van der Vorst (Henk); J. Rommes

    2008-01-01

    textabstractIn this chapter we present the principles of the space-mapping iteration techniques for the efficient solution of optimization problems. We also show how space-mapping optimization can be understood in the framework of defect correction. We observe the difference between the solution

  12. Space mapping and defect correction

    NARCIS (Netherlands)

    Echeverría, D.; Lahaye, D.; Hemker, P.W.; Schilders, W.H.A.; van der Vorst, H.A.; Rommes, J.

    2008-01-01

    In this chapter we present the principles of the space-mapping iteration techniques for the efficient solution of optimization problems. We also show how space-mapping optimization can be understood in the framework of defect correction. We observe the difference between the solution of the

  13. Grassman defectivity à la Terracini

    Directory of Open Access Journals (Sweden)

    Carla Dionisi

    2001-11-01

    Full Text Available This work is a modern rivisitation of a classical paper by nA. Terracini, going back to 1915, which suggests an elementary but powerful method for studying Grassmann defective varieties. In particular, the case of Veronese surfaces is completely understood, giving a positive answer to the so-called Waring problem for pairs of homogeneous polynomials in three variables.

  14. Defects and an unusual superconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Gor' kov, L.P.; Kalugin, P.A.

    1985-03-10

    If the superconducting gap in a pure material has zeros on an entire line along the Fermi surface, the state density is finite at epsilon = 0, beginning with the lowest defect concentrations. The splitting of the superconducting transition by impurities, U/sub 1-x/Th/sub x/Be/sub 13/ is discussed.

  15. Delamination initiated by a defect

    DEFF Research Database (Denmark)

    Biel, Anders; Toftegaard, Helmuth Langmaack

    2016-01-01

    Composite materials in wind turbines are mainly joined with adhesives. Adhesive joining is preferable since it distributes the stresses over a larger area. This study shows how a defect can influence the fracture behaviour of adhesively joined composite. Repeated experiments are performed using d...

  16. Ocular defects in cerebral palsy

    Directory of Open Access Journals (Sweden)

    Katoch Sabita

    2007-01-01

    Full Text Available There is a high prevalence of ocular defects in children with developmental disabilities. This study evaluated visual disability in a group of 200 cerebral palsy (CP patients and found that 68% of the children had significant visual morbidity. These findings emphasize the need for an early ocular examination in patients with CP.

  17. Polymicrobial Chronic Infection Including Acinetobacter Baumannii in a Plated Segmental Defect in the Rat Femur

    National Research Council Canada - National Science Library

    Tsukayama, Dean T

    2008-01-01

    .... This model could then be used to assess the combined therapy of an osteogenic agent to stimulate bone formation while local and system antibiotic therapy was being applied to control the polymicrobial infection...

  18. States of Stress and Strain in Adhesive Joints Including Photoelastic Imaging of Defects in Adherends.

    Science.gov (United States)

    1980-11-30

    T = Dt/a 2 , R = ra, C = c/ cSAT with D a constant diffusion coefficient. 19 II By using a suitable substitution this equation is Bessel’s of order...to allow a joint to be made at the cut has been very carefully examined. A custom built chain wrench closes the gap too quickly, and a range of

  19. Cell sheet-based tissue engineering for fabricating 3-dimensional heart tissues.

    Science.gov (United States)

    Shimizu, Tatsuya

    2014-01-01

    In addition to stem cell biology, tissue engineering is an essential research field for regenerative medicine. In contrast to cell injection, bioengineered tissue transplantation minimizes cell loss and has the potential to repair tissue defects. A popular approach is scaffold-based tissue engineering, which utilizes a biodegradable polymer scaffold for seeding cells; however, new techniques of cell sheet-based tissue engineering have been developed. Cell sheets are harvested from temperature-responsive culture dishes by simply lowering the temperature. Monolayer or stacked cell sheets are transplantable directly onto damaged tissues and cell sheet transplantation has already been clinically applied. Cardiac cell sheet stacking produces pulsatile heart tissue; however, lack of vasculature limits the viable tissue thickness to 3 layers. Multistep transplantation of triple-layer cardiac cell sheets cocultured with endothelial cells has been used to form thick vascularized cardiac tissue in vivo. Furthermore, in vitro functional blood vessel formation within 3-dimensional (3D) tissues has been realized by successfully imitating in vivo conditions. Triple-layer cardiac cell sheets containing endothelial cells were layered on vascular beds and the constructs were media-perfused using novel bioreactor systems. Interestingly, cocultured endothelial cells migrate into the vascular beds and form perfusable blood vessels. An in vitro multistep procedure has also enabled the fabrication of thick, vascularized heart tissues. Cell sheet-based tissue engineering has revealed great potential to fabricate 3D cardiac tissues and should contribute to future treatment of severe heart diseases and human tissue model production.

  20. Free toe pulp flap for finger pulp and volar defect reconstruction

    Directory of Open Access Journals (Sweden)

    Jyoshid R Balan

    2016-01-01

    Full Text Available Background: Fingertip injury requiring flap cover is very common in the modern era. The ideal cover should fulfill both functional and aesthetic improvement. Materials and Methods: From June 2015 to April 2016, we performed seven free toe pulp flaps for finger defect reconstruction. All patients were males. Five flaps were done in emergency post-traumatic cases, and two were done in elective set up. The cases included reconstruction of three thumbs, one index and one ring finger in an emergency set up and two ring fingers in the elective. Thumb reconstruction was done with great toe lateral pulp and the other digits reconstructed with second toe pulp flap. Follow-up evaluation included both functional and aesthetic assessment. Results: Five flaps survived completely, one suffered partial loss, and one flap failed completely. The median follow-up period was 9 months. The median duration of surgery was 255 min (range 210 to 300 min. The median two-point discrimination was 6.5 mm (range 4–8 mm. There was the return of temperature sensation in all patients; two had cold intolerance. The Semmes-Weinstein monofilament score varied from 3.61 to 5.07 (median filament index value 4.31/pressure value of 2 g/mm2. Three patients had delayed donor site wound healing. Conclusions: The free toe pulp flap is an efficient choice for fingertip and volar finger defects reconstruction with an excellent tissue match.

  1. [Prosthodontic treatment of edentulous patients with postoperative mandibular defects of oncological origin].

    Science.gov (United States)

    Arutyunov, A S; Shanidze, Z L; Tsareva, E V; Arutyunov, S D

    2018-01-01

    The aim of the study was clinical and bacteriological approbation of improved obturator dentures with soft lining. The study involved 116 patients (68 females and 48 males aged 47-78) with edentulous jaws and side palatal defect of oncological origin. Improved elastic obturator maxilla dentures in patients with palatal defects proved to have better stability and provides better comfort effectively preventing inflammation of prosthetic bed soft tissues.

  2. Is bone transplantation the gold standard for repair of alveolar bone defects?

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    Cassio Eduardo Raposo-Amaral

    2014-01-01

    Full Text Available New strategies to fulfill craniofacial bone defects have gained attention in recent years due to the morbidity of autologous bone graft harvesting. We aimed to evaluate the in vivo efficacy of bone tissue engineering strategy using mesenchymal stem cells associated with two matrices (bovine bone mineral and α-tricalcium phosphate, compared to an autologous bone transfer. A total of 28 adult, male, non-immunosuppressed Wistar rats underwent a critical-sized osseous defect of 5 mm diameter in the alveolar region. Animals were divided into five groups. Group 1 (n = 7 defects were repaired with autogenous bone grafts; Group 2 (n = 5 defects were repaired with bovine bone mineral free of cells; Group 3 (n = 5 defects were repaired with bovine bone mineral loaded with mesenchymal stem cells; Group 4 (n = 5 defects were repaired with α-tricalcium phosphate free of cells; and Group 5 (n = 6 defects were repaired with α-tricalcium phosphate loaded with mesenchymal stem cells. Groups 2–5 were compared to Group 1, the reference group. Healing response was evaluated by histomorphometry and computerized tomography. Histomorphometrically, Group 1 showed 60.27% ± 16.13% of bone in the defect. Groups 2 and 3 showed 23.02% ± 8.6% (p = 0.01 and 38.35% ± 19.59% (p = 0.06 of bone in the defect, respectively. Groups 4 and 5 showed 51.48% ± 11.7% (p = 0.30 and 61.80% ± 2.14% (p = 0.88 of bone in the defect, respectively. Animals whose bone defects were repaired with α-tricalcium phosphate and mesenchymal stem cells presented the highest bone volume filling the defects; both were not statistically different from autogenous bone.

  3. Clinical and Radiological Regeneration of Large and Deep Osteochondral Defects of the Knee by Bone Augmentation Combined With Matrix-Guided Autologous Chondrocyte Transplantation.

    Science.gov (United States)

    Zellner, Johannes; Grechenig, Stephan; Pfeifer, Christian G; Krutsch, Werner; Koch, Matthias; Welsch, Goetz; Scherl, Madeleine; Seitz, Johannes; Zeman, Florian; Nerlich, Michael; Angele, Peter

    2017-11-01

    Large osteochondral defects of the knee are a challenge for regenerative treatment. While matrix-guided autologous chondrocyte transplantation (MACT) represents a successful treatment for chondral defects, the treatment potential in combination with bone grafting by cancellous bone or bone block augmentation for large and deep osteochondral defects has not been evaluated. To evaluate 1- to 3-year clinical outcomes and radiological results on magnetic resonance imaging (MRI) after the treatment of large osteochondral defects of the knee with bone augmentation and MACT. Special emphasis is placed on different methods of bone grafting (cancellous bone grafting or bone block augmentation). Case series; Level of evidence, 4. Fifty-one patients were included. Five patients were lost to follow-up. This left 46 patients (mean age, 28.2 years) with a median follow-up time of 2 years. The 46 patients had 47 deep, large osteochondral defects of the knee joint (1 patient with bilateral defects; mean defect size, 6.7 cm 2 ). The origin of the osteochondral defects was osteochondritis dissecans (n = 34), osteonecrosis (n = 8), or subchondral cysts (n = 5). Depending on the depth, all defects were treated by cancellous bone grafting (defect depth ≤10 mm; n = 16) or bone block augmentation (defect depth >10 mm; n = 31) combined with MACT. Clinical outcomes were followed at 3 months, 6 months, 1 year, 2 years, and 3 years and evaluated using the International Knee Documentation Committee (IKDC) score and Cincinnati score. A magnetic resonance imaging (MRI) evaluation was performed at 1 and 2 years, and the magnetic resonance observation of cartilage repair tissue (MOCART) score with additional specific subchondral bone parameters (bone regeneration, bone signal quality, osteophytes, sclerotic areas, and edema) was analyzed. The clinical outcome scores revealed a significant increase at follow-up (6 months to 3 years) compared with the preclinical results. The median IKDC score

  4. Surgical techniques on periodontal plastic surgery and soft tissue regeneration: consensus report of Group 3 of the 10th European Workshop on Periodontology.

    Science.gov (United States)

    Sanz, Mariano; Simion, Massimo

    2014-04-01

    The scope was to review the three main clinical indications in periodontal plastic surgical procedures. To review the fundamental principles in periodontal plastic surgery, the main surgical designs in flap surgery applied to the treatment of recessions, peri-implant soft tissue deficiencies and soft tissue ridge augmentation, as well as the surgical principles of using autologous connective tissue grafts and soft tissue substitutes. In the pre-operative phase, the key elements are the control of prognostic factors affecting the patient, namely oral hygiene, tobacco smoking cessation and systemic disease control. In the operative phase, the principles of flap design, mobilization, advancement, adaptation and stabilization. In the post-operative phase infection control, including effective oral hygiene measures, antiseptic treatment and other medications. In single recession defects, the most widely used flap technique is the coronally advanced flap and in specific clinical situations the laterally positioned flap. In multiple recession defects, the number of defects and their location and depth guide the surgical design, being one design with and the other without vertical releasing incisions. When flaps are used in combination with grafts the tunnel flap is also used extensively. The key elements are the donor site selection and harvesting technique, its tissue integration and volume stability. Given the current evidence, various clinical recommendations on the use of flaps and grafts are provided. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Differentially expressed genes in embryonic cardiac tissues of mice lacking Folr1 gene activity

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    Schwartz Robert J

    2007-11-01

    Full Text Available Abstract Background Heart anomalies are the most frequently observed among all human congenital defects. As with the situation for neural tube defects (NTDs, it has been demonstrated that women who use multivitamins containing folic acid peri-conceptionally have a reduced risk for delivering offspring with conotruncal heart defects 123. Cellular folate transport is mediated by a receptor or binding protein and by an anionic transporter protein system. Defective function of the Folr1 (also known as Folbp1; homologue of human FRα gene in mice results in inadequate transport, accumulation, or metabolism of folate during cardiovascular morphogenesis. Results We have observed cardiovascular abnormalities including outflow tract and aortic arch arterial defects in genetically compromised Folr1 knockout mice. In order to investigate the molecular mechanisms underlying the failure to complete development of outflow tract and aortic arch arteries in the Folr1 knockout mouse model, we examined tissue-specific gene expression difference between Folr1 nullizygous embryos and morphologically normal heterozygous embryos during early cardiac development (14-somite stage, heart tube looping (28-somite stage, and outflow track septation (38-somite stage. Microarray analysis was performed as a primary screening, followed by investigation using quantitative real-time PCR assays. Gene ontology analysis highlighted the following ontology groups: cell migration, cell motility and localization of cells, structural constituent of cytoskeleton, cell-cell adhesion, oxidoreductase, protein folding and mRNA processing. This study provided preliminary data and suggested potential candidate genes for further description and investigation. Conclusion The results suggested that Folr1 gene ablation and abnormal folate homeostasis altered gene expression in developing heart and conotruncal tissues. These changes affected normal cytoskeleton structures, cell migration and

  6. Osteogenesis and chondrogenesis of biomimetic integrated porous PVA/gel/V-n-HA/pa6 scaffolds and BMSCs construct in repair of articular osteochondral defect.

    Science.gov (United States)

    Li, Xiang; Li, Yubao; Zuo, Yi; Qu, Dan; Liu, Yiming; Chen, Tao; Jiang, Nan; Li, Hui; Li, Jihua

    2015-10-01

    A novel bi-layered osteochondral scaffold, including of PVA/Gel/V layer for the cartilage and n-HA/PA6 layer for the subchondral bone, has been proposed to evaluate the potential of the engineered of osteochondral grafts in repairing articular osteochondral defects in rabbits. The two different layers of the scaffolds were seeded with allogenic bone marrow-derived stem cells (BMSCs), which were chondrogenically and osteogenically induced respectively. The critical-size osteochondral defects were created in the knees of adult rabbits. The defects were treated with cell-bi-layered constructs (Group A), bi-layered constructs (Group B) and untreated group C as control group. The adhesion, proliferation and differentiation of BMSCs were demonstrated by immunohistochemical staining and scanning electron microscopy (SEM) in vitro. Cell survival was tracked via fluorescent labeling in vivo. Overall, the porous PVA/Gel/V-n-HA/PA6 scaffold was compatible and had no negative effects on the BMSCs in vitro culture. The cell-bi-layered scaffolds showed superior repair results as compared to the control group using gross examination and histological assessment. With BMSCs implantation, the two different layers of the composite biomimetic scaffolds provided a suitable environment for cells to form respective tissue. Simultaneously, the RT-PCR results confirmed the expression of specific extracellular matrix (ECM) markers for cartilaginous or osteoid tissue. This investigation showed that the porous PVA/Gel/V-n-HA/PA6 scaffold is a potential matrix for treatment of osteochondral defects, and the method of using chondrogenically and osteogenically differentiated BMSCs as seed cells on each layer might be a promising strategy in repair of articular osteochondral defect due to enhanced chondrogenesis and osteogenesis. © 2015 Wiley Periodicals, Inc.

  7. Software defect prevention based on human error theories

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    Fuqun HUANG

    2017-06-01

    Full Text Available Software defect prevention is an important way to reduce the defect introduction rate. As the primary cause of software defects, human error can be the key to understanding and preventing software defects. This paper proposes a defect prevention approach based on human error mechanisms: DPeHE. The approach includes both knowledge and regulation training in human error prevention. Knowledge training provides programmers with explicit knowledge on why programmers commit errors, what kinds of errors tend to be committed under different circumstances, and how these errors can be prevented. Regulation training further helps programmers to promote the awareness and ability to prevent human errors through practice. The practice is facilitated by a problem solving checklist and a root cause identification checklist. This paper provides a systematic framework that integrates knowledge across disciplines, e.g., cognitive science, software psychology and software engineering to defend against human errors in software development. Furthermore, we applied this approach in an international company at CMM Level 5 and a software development institution at CMM Level 1 in the Chinese Aviation Industry. The application cases show that the approach is feasible and effective in promoting developers’ ability to prevent software defects, independent of process maturity levels.

  8. The role of defects and doping in 2D graphene sheets and 1D nanoribbons.

    Science.gov (United States)

    Terrones, Humberto; Lv, Ruitao; Terrones, Mauricio; Dresselhaus, Mildred S

    2012-06-01

    Defects are usually seen as imperfections in materials that could significantly degrade their performance. However, at the nanoscale, defects could be extremely useful since they could be exploited to generate novel, innovative and useful materials and devices. Graphene and graphene nanoribbons are no exception. This review therefore tries to categorize defects, emphasize their importance, introduce the common routes to study and identify them and to propose new ways to construct novel devices based on 'defective' graphene-like materials. In particular, we will discuss defects in graphene-like systems including (a) structural (sp(2)-like) defects, (b) topological (sp(2)-like) defects, (c) doping or functionalization (sp(2)- and sp(3)-like) defects and (d) vacancies/edge type defects (non-sp(2)-like). It will be demonstrated that defects play a key role in graphene physicochemical properties and could even be critical to generate biocompatible materials. There are numerous challenges in this emerging field, and we intend to provide a stimulating account which could trigger new science and technological developments based on defective graphene-like materials that could be introduced into other atomic layered materials, such as BN, MoS(2) and WS(2), not discussed in this review.

  9. Ambient air pollution and birth defects in brisbane, australia.

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    Craig A Hansen

    Full Text Available BACKGROUND: Birth defects are a major public health concern as they are the leading cause of neonatal and infant mortality. Observational studies have linked environmental pollution to adverse birth outcomes, including congenital anomalies. This study examined potential associations between ambient air pollution and congenital heart defects and cleft lip or palate among births in Brisbane, Australia (1998-2004. METHODS: Ambient air pollution levels were averaged over weeks 3-8 of pregnancy among 150,308 births. Using a case-control design, we used conditional logistic regression and matched cases to 5 controls. Analyses were conducted using all births, and then births where the mother resided within 6 and 12 kilometers of an ambient air quality monitor. FINDINGS: When analyzing all births there was no indication that ambient air pollution in Brisbane was associated with a higher risk of cardiac defects. Among births where the mother resided within 6 kilometers of an ambient air quality monitor, a 5 ppb increase in O(3 was associated with an increased risk of pulmonary artery and valve defects (OR 2.96, 95% CI: 1.34, 7.52 while a 0.6 ppb increase in SO(2 was associated with an increased risk of aortic artery and valve defects (OR 10.76, 95% CI: 1.50, 179.8. For oral cleft defects among all births, the only adverse association was between SO(2 and cleft lip with or without cleft palate (OR 1.27, 95% CI: 1.01, 1.62. However, various significant inverse associations were also found between air pollutants and birth defects. CONCLUSIONS: This study found mixed results and it is difficult to conclude whether ambient air pollution in Brisbane has an adverse association with the birth defects examined. Studies using more detailed estimates of air pollution exposure are needed.

  10. Congenital Heart Defects and Receipt of Special Education Services.

    Science.gov (United States)

    Riehle-Colarusso, Tiffany; Autry, Andrew; Razzaghi, Hilda; Boyle, Coleen A; Mahle, William T; Van Naarden Braun, Kim; Correa, Adolfo

    2015-09-01

    We investigated the prevalence of receipt of special education services among children with congenital heart defects (CHDs) compared with children without birth defects. Children born from 1982 to 2004 in metropolitan Atlanta with CHDs (n = 3744) were identified from a population-based birth defect surveillance program; children without birth defects (n = 860 715) were identified from birth certificates. Cohorts were linked to special education files for the 1992-2012 school years to identify special education services. Children with noncardiac defects or genetic syndromes were excluded; children with CHDs were classified by presence or absence of critical CHDs (ie, CHDs requiring intervention by age one year). We evaluated the prevalence of receipt of special education services and prevalence rate ratios using children without birth defects as a reference. Compared with children without birth defects, children with CHDs were 50% more likely to receive special education services overall (adjusted prevalence rate ratio [aPRR] = 1.5; 95% confidence interval [CI]: 1.4-1.7). Specifically, they had higher prevalence of several special education categories including: intellectual disability (aPRR = 3.8; 95% CI: 2.8-5.1), sensory impairment (aPRR = 3.0; 95% CI: 1.8-5.0), other health impairment (aPRR = 2.8; 95% CI: 2.2-3.5), significant developmental delay (aPRR = 1.9; 95% CI: 1.3-2.8), and specific learning disability (aPRR = 1.4; 95% CI: 1.1-1.7). For most special education services, the excess prevalence did not vary by presence of critical CHDs. Children with CHDs received special education services more often than children without birth defects. These findings highlight the need for special education services and the importance of developmental screening for all children with CHDs. Copyright © 2015 by the American Academy of Pediatrics.

  11. Defects and Rearrangements in Disordered Solids

    Science.gov (United States)

    Wijtmans, Sven

    In this thesis, I will investigate the properties of disordered materials under strain. Disordered materials encompass a large variety of materials, including glasses, polymers, granular matter, dense colloids, and gels. There is currently no constitutive equation based on microscopic observables that describes these materials. Given the prevalence and usefulness of these materials, we derive tools to aid our understanding of them. We develop a new method to isolate localized defects from extended vibrational modes in disordered solids. This method augments particle interactions with an artificial potential that acts as a high-pass filter: it preserves small-scale structures while pushing extended vibrational modes to higher frequencies. The low-frequency modes that remain are ``bare" defects; they are exponentially localized without the quadrupolar tails associated with elastic interactions. We demonstrate that these localized excitations are excellent predictors of plastic rearrangements in the solid. We characterize several of the properties of these defects that appear in mesoscopic theories of plasticity, including their distribution of energy barriers, number density, and size, which is a first step in testing and revising continuum models for plasticity in disordered solids. We additionally study the properties of rearrangement types in 2D disordered packings of particles with a harmonic potential at a range of packing fractions above jamming. We develop a generalizable procedure that classifies events by stress drop, energy drop, and reversibility under two protocols. Somewhat surprisingly, we find a large population of contact change events that have no associated stress drop. Reversible events become more common at high pressures above a packing fraction of phi=0.865, at which point line reversible events are more common than loop reversible events. At low pressures, irreversible events are associated with spatially extended events, while at high

  12. Aging changes in organs - tissue - cells

    Science.gov (United States)

    ... the passages inside the body, such as the gastrointestinal system, are made of epithelial tissue. Muscle tissue includes ... including changes in: Hormone production Immunity The skin Sleep Bones, muscles, and joints The breasts The face ...

  13. Use of platelet rich fibrin in a fenestration defect around an implant

    Directory of Open Access Journals (Sweden)

    R Vijayalakshmi

    2012-01-01

    Full Text Available Guided bone regeneration (GBR in implant therapy is especially useful for implant placement with dehiscence defects or fenestration defects. In alveolar ridges with marked facial/buccal depressions or in knifeedge alveolar crests, the position and direction of fixture placement is restricted. Improvement of alveolar ridge morphology becomes possible with GBR. This article describes a case in which the fenestration defect around an implant was treated by the application of platelet rich fibrin, a second generation platelet concentrate along with bone graft, and guided tissue regeneration membrane.

  14. Rectus Abdominis Muscle Malignant Fibrous Histiocytoma Causing a Large Abdominal Wall Defect: Reconstruction with Biological Mesh

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    Evangelos Falidas

    2014-01-01

    Full Text Available Malignant fibrous histiocytoma (MFH is a common soft tissue sarcoma usually involving limbs and retroperitoneum. MFH of the rectus abdominis muscle is extremely rare. Surgery in similar cases leads to large abdominal wall defects needing reconstruction. Biological and synthetic laminar absorbable prostheses are available for the repair of hernia defects in the abdominal wall. They share the important feature of being gradually degraded in the host, resulting the formation of a neotissue. We herein report the case of an 84-year-old man with MFH of the rectus abdominis muscle which was resected and the large abdominal wall defect was successfully repaired with a biological mesh.

  15. Does a muscle flap accelerate wound healing of gastric wall defects compared with an omental flap?

    Science.gov (United States)

    Hishida, Masashi; Toriyama, Kazuhiro; Yagi, Shunjiro; Ebisawa, Katsumi; Morishita, Tsuyoshi; Takanari, Keisuke; Kamei, Yuzuru

    2015-06-01

    Most often used for reconstruction at superficial sites, a muscle flap recently was reported to promote clinical wound healing in a duodenal defect. We therefore examined whether a muscle flap could promote wound healing comparably to an omental flap in rats with gastric wall defects. After perforation of the centre of the anterior gastric wall, rats were divided into 2 groups. In the muscle group, a muscle flap was fixed to the defect; in the omentum group, an omental flap was placed over the defect. We histopathologically compared tissue responses during gastric wall healing. While stratified villi had completely covered the defect by day 7 in both groups, scar maturation differed. Scar tissue persisted in the muscle group, but was gradually replaced by adipose tissue in the omentum group. Both muscle and omental flaps accelerated gastric wall wound healing. A muscle flap is an excellent alternative for repair of gastric defects when no omental flap is available. Copyright © 2015. Published by Elsevier Ltd.

  16. Quality control in tissue banking--ensuring the safety of allograft tissues.

    Science.gov (United States)

    Humphries, Linda K; Mansavage, Vicki L

    2006-09-01

    DESPITE FEDERAL REGULATIONS for tissue-banking practices, inadequate quality control led to the largest allograft tissue recall in history in October 2005. THE RECALL INCLUDED all allograft tissues obtained from 761 donors and distributed by five tissue banks. Many of these tissues already had been implanted and were unrecoverable. THIS ARTICLE DESCRIBES the many tissue-banking industry variables, including donor selection and testing and tissue recovery, processing, and preservation. QUESTIONS THAT HEALTH CARE providers can ask to determine which tissue banks' quality control measures best ensure the safety of the allografts they provide also are included.

  17. Predicting internal red oak (Quercus rubra) log defect features using surface defect defect measurements

    Science.gov (United States)

    R. Edward. Thomas

    2013-01-01

    Determining the defects located within a log is crucial to understanding the tree/log resource for efficient processing. However, existing means of doing this non-destructively requires the use of expensive x-ray/CT (computerized tomography), MRI (magnetic resonance imaging), or microwave technology. These methods do not lend themselves to fast, efficient, and cost-...

  18. Supermicrosurgical reconstruction of knee defect using superior medial genicular perforator as a recipient vessel

    Directory of Open Access Journals (Sweden)

    Hoon Kim

    2014-09-01

    Full Text Available A 24-year-old male presented after being involved in a motorcycle accident and was found to have soft tissue defects of the knee with exposure of patella. Due to the severe injury from the popliteal fossa to the posterior aspects of the lower leg, repair with a free flap from anterolateral thigh perforator was planned instead of local calf muscle flap. Preoperative angiography was performed, and it showed that superior medial genicular perforator was patent compared with unreliable filling of the superior lateral genicular perforator. The soft tissue defect was repaired using the superior medial genicular perforator as the recipient vessel. This was performed by creating perforator to perforator anastomosis (supermicrosurgery. The flap survived successfully, and the patient was able to ambulate in a few weeks without serious complications. This case indicates that superior medial genicular perforator can be used as the recipient vessel for covering the soft tissue defects of the knee caused by blunt injury.

  19. Trends in Tissue Engineering for Blood Vessels

    Science.gov (United States)

    Nemeno-Guanzon, Judee Grace; Lee, Soojung; Berg, Johan Robert; Jo, Yong Hwa; Yeo, Jee Eun; Nam, Bo Mi; Koh, Yong-Gon; Lee, Jeong Ik

    2012-01-01

    Over the years, cardiovascular diseases continue to increase and affect not only human health but also the economic stability worldwide. The advancement in tissue engineering is contributing a lot in dealing with this immediate need of alleviating human health. Blood vessel diseases are considered as major cardiovascular health problems. Although blood vessel transplantation is the most convenient treatment, it has been delimited due to scarcity of donors and the patient's conditions. However, tissue-engineered blood vessels are promising alternatives as mode of treatment for blood vessel defects. The purpose of this paper is to show the importance of the advancement on biofabrication technology for treatment of soft tissue defects particularly for vascular tissues. This will also provide an overview and update on the current status of tissue reconstruction especially from autologous stem cells, scaffolds, and scaffold-free cellular transplantable constructs. The discussion of this paper will be focused on the historical view of cardiovascular tissue engineering and stem cell biology. The representative studies featured in this paper are limited within the last decade in order to trace the trend and evolution of techniques for blood vessel tissue engineering. PMID:23251085

  20. Stem Cells Cultured on Beta Tricalcium Phosphate (β-TCP) in Combination with Recombinant Human Platelet-Derived Growth Factor - BB (rh-PDGF-BB) for the Treatment of Human Infrabony Defects.

    Science.gov (United States)

    Dhote, Roshani; Charde, Priti; Bhongade, Manohar; Rao, Jyotsana

    2015-01-01

    Knowledge gained from the field of tissue engineering, helped to develop a biological substitute that promotes tissue regeneration. The usual biological substitute consists of stem cells, growth factors and an appropriate scaffold. The present randomized controlled clinical and radiographic study was undertaken to evaluate the effectiveness of mesenchymal stem cells cultured on beta tricalcium phosphate (β-TCP) in combination with rh-PDGF-BB in treatment of infrabony defect in humans. A total of 24 infrabony defects in 14 systemically healthy patients were selected for the present study. The selected defects exhibited a probing pocket depth (PPD) of ≥ 5 mm and depth of infrabony component ≥ 3 mm as assessed by clinical and radiographic measurements and later confirmed by intrasurgical measurement. Baseline measurements included were Plaque Index (PI), Papillary Bleeding Index (PBI), Probing Pocket Depth (PPD), Relative gingival marginal level (RGML), Relative Clinical Attachment Level (R-CAL) and Radiographic Defect Depth (DD) and linear bone growth (LBG). 6 weeks after initial therapy, the defects were randomly assigned to either test group or control group. The control group was treated by an open flap debridement (OFD) only, while the test group was treated by a Stem cells cultured on β-TCP in combination with rh-PDGF-BB. All the measurements recorded preoperatively were repeated at 6 months after the surgery. The efficacy of each treatment modality was investigated through statistical analysis. Mean probing pocket depth reduction was significantly greater in test group (4.50 ± 1.08 mm) compared to the OFD group (3.50 ± 0.90 mm). Mean gains in clinical attachment level was 3.91 ± 1.37 mm in the test group and 2.08 ± 0.90 mm in the control group. The mean increase in gingival recession (GR) was less in test group (0.58 ± 0.79 mm) compared to OFD group (1.4 ± 0.66 mm). Radiographic defect depth reduction was greater in the test group (3.50 ± 0.67 mm

  1. 3D Volumetric Modeling and Microvascular Reconstruction of Irradiated Lumbosacral Defects After Oncologic Resection

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    Emilio Garcia-Tutor

    2016-12-01

    Full Text Available Background: Locoregional flaps are sufficient in most sacral reconstructions. However, large sacral defects due to malignancy necessitate a different reconstructive approach, with local flaps compromised by radiation and regional flaps inadequate for broad surface areas or substantial volume obliteration. In this report, we present our experience using free muscle transfer for volumetric reconstruction in such cases, and demonstrate 3D haptic models of the sacral defect to aid preoperative planning.Methods: Five consecutive patients