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Sample records for bone lengthening

  1. Study of treating tibial large bone defect with migration of lengthened bone segment in goats

    Institute of Scientific and Technical Information of China (English)

    YANG liu; LI Qi-hong; ZHOU Zhong-an; TAN Zu-jian; PENG Yi-liang

    2001-01-01

    To study the effects of migration of lengthened bone segment (MLBS) on the blood circulation and repair remodeling process at the ends of large bone defect of a long bone. Methods: A total of 18 adult goats were used and more than 35% of the original length of their left tibia was resected. Upper metaphysiotomy to lengthen upper part of the tibia was done and the lengthened bone segment was migrated to repair the large bone defect. The results were observed with X-ray films, Chinese-ink permeated transparent sections and histological study. Results: After MLBS, the defect ends of the tibia were supplied with abundant blood circulation which resulted in rapid and solid long bone healing. Conclusion: Repair of large bone defect of long bones with MLBS provides a new method for clinical practice.

  2. Lengthening of the first metatarsal bone. A case of congenital shortening

    OpenAIRE

    Amillo, S.; Gil-Albarova, J. (Jorge); Pampliega, T. (Tomás)

    1991-01-01

    A 14-year-old boy had a congenital shortening of the first right metatarsal bone, with overloading of the central metatarsals and medial deviation of the second toe. A percutaneous osteotomy and slow distraction by an external fixator for 10 weeks lengthened the bone from 32 mm to 60 mm. After the distraction, a bone graft was performed, and tenotomies and a capsulotomy corrected a threatening subluxation. Consolidation of the lengthening focus required 16 weeks.

  3. Ilizarov Method for Bone Lengthening and Defect Management Review of Contemporary Literature.

    Science.gov (United States)

    Gubin, Alexander; Borzunov, Dmitry; Malkova, Tatiana

    2016-06-01

    Since its origination in the middle of the past century, the Ilizarov method has advanced greatly and has become a viable method for bone lengthening, severe deformity correc- tion, and defect management. As the reported studies show, it remains one of the most used tools for bone reconstruction. The original method and its modifications continue to be the topic of interest for orthopaedic scientists as evidenced by the number of clinical studies on the Ilizarov method that have been published in orthopaedic journals in the period from 2000 through 2014, most of which present the out- comes of treating large series of patients using distraction osteogenesis for bone lengthening, defect management, and deformity correction. We made a review of contemporary clinical studies on the Ilizarov method used for bone length- ening and defect management. PMID:27281320

  4. [The value of methods of bone regeneration evaluation in limb lengthening by the Wagner, Ilizarov methods and by physeal distraction].

    Science.gov (United States)

    Tesiorowski, Maciej; Kacki, Wojciech; Jasiewicz, Barbara; Rymarczyk, Adrian; Sebastianowicz, Piotr

    2005-01-01

    Limb lengthening is a long-lasting process, and during new bone formation different complications may occur. Due to this, early diagnosis of disturbances of new bone formation leading to such complications is of importance. The goal of this study is to analyze already used methods of regenerate evaluation. Material consists of retrospective data of 237 patients, who underwent limb lengthening between 1983 and 2002 by one of three methods: Wagner method, Ilizarow method and physeal distraction. During femoral lengthening by Wagner method appropriate shape of regenerate according to Hamanishi was observed in 9 cases (29.0%), and during tibia lengthening--only in 1 case (6.7%). During femoral lengthening by physeal distraction appropriate shape of regenerate (A or B according to Hamanishi) was observed in 24 cases (77.4%), and during tibia lengthening--in 11 cases (78.6%). During femoral lengthening by Ilizarow method appropriate shape of regenerate was observed in 51 cases (72.9%), and during tibia lengthening--in 46 cases (66.7%). Only in Wagner method a correlation between abnormal regenerate shape and bone consolidation complications was noted. Methods of evaluation of bone regeneration during distraction osteogenesis give only descriptive assessment. So far parameters applied for evaluation of distraction osteogenesis in Ilizarow method and physeal distraction do not allow for detailed assessment of bone regeneration process.

  5. DISTRACTION OF OSTEOGENESIS AND LENGTHENING OF CRANIOFACIAL BONE-PRELIMINARY REPORT OF AN EXPERIMENTAL RESEARCH

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective The method of bone lengthening by distraction of callus was used on dog mandible as a model to study the capability and changes of membranous bone during distraction osteogenesis. Methods 15 dogs aged 5~7 months were chosen as the subjects. The operation included a unilateral or bilateral periosteal preserving corti cotomy of mandibular bone, and an introral mini lengthening device were fixed to the buccal side of the mandible. After 7d, the mandible was lengthened lmm/d for 20d and then held in internal fixation for 7~ 140d (1 ~ 20 weeks). Results The dogs were killed at 3 times. Anthropometric measurements, X-ray examination and histological observa tion were conducted and conformed that the distracted bone had formed in the expanded zone successfully. Conclu sion The results suggested that we could use the DO technique in the area of craniofacial clinic. The strong ability of generating new bone in membranous skeleton by DO technique should be further demonstrated in the future.

  6. Scintigraphic evaluation of bone lengthening by Ilizarov technique; Avaliacao cintigrafica do alongamento osseo pela tecnica de Ilizarov

    Energy Technology Data Exchange (ETDEWEB)

    Wolosker, Sara; Knackfuss, Irocy; Marchiori, Edson

    1996-07-01

    One of the main problems in limb lengthening is the difficulty on the assessment of the regenerated bone healing, since there are no reliable methods for its in vitro evaluation of restoration and mechanical integrity. New bone formation depends on the interaction between blood supply and mechanical distraction. The uptake of 99m-Tc-MDP has been shown to be a function of both regional blood flow and bone formation. Therefore, we propose the use of sequential three phase bone scans as another method in monitoring the regenerated bone formation in the Ilizarov technique of limb lengthening. Our preliminary results are shown in this paper. (author)

  7. The effect of latency on bone lengthening force and bone mineralization: an investigation using strain gauge mounted on internal distractor device

    OpenAIRE

    Wang Jue; Wu Zhongying; Liu Yaxiong; Li Dichen; Singare Sekou

    2006-01-01

    Abstract Background The purpose of this study was to investigate the effect of latency on the development of bone lengthening force and bone mineralization during mandible distraction osteogenesis. Methods Distraction tensions were investigated at different latency period in 36 rabbits using internal unilateral distractor. Strain gauges were prepared and attached to the distractor to directly assess the level of distraction tension during mandible lengthening. The tensile force environment of...

  8. The effect of latency on bone lengthening force and bone mineralization: an investigation using strain gauge mounted on internal distractor device

    Directory of Open Access Journals (Sweden)

    Wang Jue

    2006-03-01

    Full Text Available Abstract Background The purpose of this study was to investigate the effect of latency on the development of bone lengthening force and bone mineralization during mandible distraction osteogenesis. Methods Distraction tensions were investigated at different latency period in 36 rabbits using internal unilateral distractor. Strain gauges were prepared and attached to the distractor to directly assess the level of distraction tension during mandible lengthening. The tensile force environment of the mandible of rabbit during distraction was evaluated through in vivo experiments using two gauges. The animals were divided into 3 groups each containing 12 rabbits. Latency periods of 0, 4 and 7 days respectively were observed prior to beginning distraction. The distraction protocol consisted of a lengthening rate of 1 mm once daily for 8 days, followed by a consolidation phase of 2 weeks after which the animals were killed. Biopsies specimens were taken from the distracted area at the end of the distraction period. A non-distracted area of the mandible bone served as control. The specimens were analyzed by scanning electron microscopy to assess the ultrastructural pattern, and the bone mineralization. Results The resting tension acting on the distraction gap increases through distraction. The 7-day latency groups exhibit higher tension then those of 0-day and 4-days latency groups. Quantitative energy dispersive spectral analysis confirmed that immediate distractions were associated with lower calcium and phosphate atomic weight ratio. Conclusion the latency periods could affect the bone lengthening tension and the bone mineralization process.

  9. Brachymetatarsia of the fourth metatarsal, lengthening scarf osteotomy with bone graft

    Directory of Open Access Journals (Sweden)

    Ankit Desai

    2013-09-01

    Full Text Available A 16-year-old girl presented with left fourth metatarsal shortening causing significant psychological distress. She underwent lengthening scarf osteotomy held with an Omnitech® screw (Biotech International, France with the addition of two 1 cm cancellous cubes (RTI Biologics, United States. A lengthening z-plasty of the extensor tendons and skin were also performed. At 6 weeks the patient was fully weight bearing and at one-year follow up, the patient was satisfied and discharged. A modified technique of lengthening scarf osteotomy is described for congenital brachymatatarsia. This technique allows one stage lengthening through a single incision with graft incorporation by 6 weeks.

  10. Orthodontic crown lengthening.

    Science.gov (United States)

    Hohlt, W F

    1992-01-01

    As comprehensive dentistry becomes more complex, procedures must be developed to save teeth once considered unsuitable for crown restoration due to inaccessible finishing lines. Orthodontic crown lengthening is less invasive than a flap procedure and does not result in crestal bone reduction. The crown lengthening procedure is a simple and time-saving remedy for a difficult restorative problem.

  11. Expression of inducible nitric oxide synthase in bone lengthening patients%骨延长患者诱导型一氧化氮合酶的表达

    Institute of Scientific and Technical Information of China (English)

    胡新永; 陈建文; 王义生

    2012-01-01

    背景:骨延长的牵张刺激如何转变为骨质再生的生物学信息至今不明确.目的:观察骨延长患者诱导型一氧化氮合酶的动态表达.方法:单侧胫腓骨延长组患者8例,分别于手术前第3天、术后第3,7,8,11,30天、停止延长时、停止延长第3,15,30天、拆除外固定器时、拆除外固定器后30 d,检测血清诱导型一氧化氮合酶水平.并设立年龄相匹配的对照组8例.结果与结论:骨延长组牵张操作开始第1天时(术后第8天),血清诱导型一氧化氮合酶即开始升高,停止延长时达高峰,这一时段各个时相骨延长组血清诱导型一氧化氮合酶均显著高于对照组(P < 0.01),停止延长3 d时的血清诱导型一氧化氮合酶亦高于对照组(P < 0.05).提示诱导型一氧化氮合酶的高表达是骨延长的分子生物学机制之一.%BACKGROUND: It is unknown that how to transfer the impetus of distraction into the message of bone regeneration in limb lengthening.OBJECTIVE: To study the dynamic expression of inducible nitric oxide synthase (iNOS) in bone lengthening patients.METHODS: Totally eight patients whose tibia and fibula are shorten in single lower limb were involved in bone lengthening group.The serum iNOS levels of the patients were measured respectively at 3 days preoperatively, at 3, 7, 8, 11, 13 days postoperatively, stopping bone lengthening, at 3, 15, 30 days after stopping bone lengthening, removing the external lengthening apparatus and at 30 days after removing the external lengthening apparatus. Eight patients with similar age to the bone lengthening group were selected as control.RESULTS AND CONCLUSION: The serum iNOS levels in the bone lengthening group began to increase at first day after the distraction (the eighth day after operation) and the peak values was at the stopping bone lengthening. The expression of iNOS in the bone lengthening group was significantly higher than that of the control group at every time point from

  12. Limb lengthening in achondroplasia

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    Sanjay K Chilbule

    2016-01-01

    Full Text Available Background: Stature lengthening in skeletal dysplasia is a contentious issue. Specific guidelines regarding the age and sequence of surgery, methods and extent of lengthening at each stage are not uniform around the world. Despite the need for multiple surgeries, with their attendant complications, parents demanding stature lengthening are not rare, due to the social bias and psychological effects experienced by these patients. This study describes the outcome and complications of extensive stature lengthening performed at our center. Materials and Methods: Eight achondroplasic and one hypochondroplasic patient underwent bilateral transverse lengthening for tibiae, humeri and femora. Tibia lengthening was carried out using a ring fixator and bifocal corticotomy, while a monolateral pediatric limb reconstruction system with unifocal corticotomy was used for the femur and humerus. Lengthening of each bone segment, height gain, healing index and complications were assessed. Subgroup analysis was carried out to assess the effect of age and bone segment on the healing index. Results: Nine patients aged five to 25 years (mean age 10.2 years underwent limb lengthening procedures for 18 tibiae, 10 femora and 8 humeri. Four patients underwent bilateral lengthening of all three segments. The mean length gain for the tibia, femur and humerus was 15.4 cm (100.7%, 9.9 cm (52.8% and 9.6 cm (77.9%, respectively. Healing index was 25.7, 25.6 and 20.6 days/cm, respectively, for the tibia, femur and humerus. An average of 33.3% height gain was attained. Lengthening of both tibia and femur added to projected height achieved as the 3 rd percentile of standard height in three out of four patients. In all, 33 complications were encountered (0.9 complications per segment. Healing index was not affected by age or bone segment. Conclusion: Extensive limb lengthening (more than 50% over initial length carries significant risk and should be undertaken only after due

  13. Humeral lengthening: Case report

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    Gajdobranski Đorđe

    2013-01-01

    Full Text Available Introduction. Difference in length of upper extremities has mainly esthetic significance and is therefore not so often a subject of operative treatment, compared to lower extremities. Case Outline. We are presenting a case of a 16­year­old patient in whom a shortening of 9 cm of the right humerus was determined at the end of growth. This shortening was the result of surgical treatment of solitary bone cyst at the proximal end of the humerus done at the age of 10 years. In order to correct the length of the humerus we applied distraction osteogenesis with a compressive­distracting device according to Mitkovic (Traffix, and we achieved the lengthening of 7.5 cm. During the period of distraction we encountered the following complications: minimal suppuration at the site of the wedges that was successfully resolved with intensive local treatment, while pain and paresthesias along the N. radialis were resolved with a temporarily slowing of the distraction process. Fixation with a plate, i.e. bone grafting was not necessary, and final functional and esthetic result was excellent. Conclusion. Successful lengthening of the shortened humerus can be achieved with a unilateral compressive­distracting device according to Mitkovic as its application up to a complete bone reconstruction does not require additional plate fixation or bone grafting. The patient was capable of performing usual daily activities during application of the device.

  14. Limb lengthening over plate

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    Ruta Kulkarni

    2012-01-01

    Conclusion: Lengthening over a plate allows early removal of external fixator and eliminates the risk of creating deep intramedullary infection as with lengthening over nail. Lengthening over plate is also applicable to children with open physis.

  15. Percutaneous Achilles Tendon Lengthening

    Science.gov (United States)

    ... require a more complex lengthening surgery. ​ Extent of ankle mobility before Achilles lengthening surgery . General Details of Procedure ... with strength and range of motion. ​ Extent of ankle mobility after Achilles lengthening surgery . Potential Complications There are ...

  16. Crown lengthening procedures

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    AA. Khoshkhonejad

    1994-06-01

    Full Text Available Nowadays, due to recent developments and researches in dental science, it is possible to preserve and restore previously extracted cases such as teeth with extensive caries, fractured or less appropriate cases for crown coverage as well as teeth with external perforation caused by restorative pins. In order to restore the teeth with preservation of periodontium, we should know thoroughly physiological aspects of periodontium and protection of Biologic Width which is formed by epithelial and supracrestal connective tissue connections. Considering biologic width is one of the principal rules of teeth restoration, otherwise we may destruct periodontal tissues. Several factors are involved in placing a restoration and one of the most important ones is where the restoration margin is terminated. Many studies have been conducted on the possible effects of restoration margin on the gingiva and due to the results of these studies it was concluded that restoration margin should be finished supragingivally. However, when we have to end the restoration under Gingival Crest, First a healthy gingival sulcus is required. Also, we should not invade the biological width. Since a normal biologic with is reported 2 mm and sound tooth tissue should be placed at least 2 mm coronal to the epithelial tissue, the distance between sound tooth tissue and crown margin should be at least 4mm. Thus, performing crown lengthening is essential to increase the clinical crown length. Basically, two objectives are considered: 1 restorative 2 esthetic (gummy smile Surgical procedure includes gingivectomy and flap procedure. Orthodontic procedure involves orthodontic extrusion or force eruption technique which is controlled vertical movements of teeth into occlusion. Besides, this procedure can also used to extrude teeth defects from the gingival tissue. By crown lengthening, tooth extraction is not required and furthermore, adjacent teeth preparation for placing a fixed

  17. Metacarpal lengthening by distraction histiogenesis in adults

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    Das Sakti

    2009-01-01

    Full Text Available Background: Metacarpal lengthening in the hand is a new application for distraction neo-histiogenesis. Metacarpal lengthening with distraction helps in improvement in pinch function. Thumb lengthening is technically easy in comparison to other metacarpals. We present the operative treatment and post-operative outcome in nine patients with amputations and congenital anomalies. Materials and Methods: Nine patients underwent distraction osteogenesis for the treatment of amputations of the hand and other congenital anomalies. The dominant right hand was operated in eight cases and the left hand in one case. There were six males and three females. Improvement of function was always the aim of surgery. Age range was between 18 and 23 years. Thumb lengthening was performed in five patients and that of the index finger in four patients. Distraction started on the fifth post-operative day at the rate of 0.25 mm/day. Sensory function and bone consolidation was assessed before fixator removal. Results: The mean duration of distraction was 51 days (range, 42-60 days and the distractor was removed at a mean of 150 days (range, 140 and 160 days and the bones were lengthened by a mean of 24 mm (range, 20-28 mm There was improvement of function in all cases. Conclusion: The metacarpal lengthening by distraction histiogenesis in congenital and traumatic amputations is safe and simple method to improve pinch function of hand.

  18. Crown lengthening revisited.

    Science.gov (United States)

    Rosenberg, E S; Cho, S C; Garber, D A

    1999-06-01

    Over the last 37 years, crown-lengthening procedures have been used predictably to restore teeth broken down from caries, trauma, and extensive wear. With crown lengthening, the dentogingival junction is "re-created" at a more apical level on the root to accommodate the junctional epithelium and the connective tissue attachment. Forced eruption can be used in addition, or as an alternative, to tooth lengthening. The authors discuss the indications for tooth lengthening, forced eruption, and orthodontic extrusion, as well as the treatment planning for these procedures.

  19. Crown lengthening and restorative treatment in mutilated molars.

    Science.gov (United States)

    Parashis, A; Tripodakis, A

    1994-03-01

    Crown lengthening has been advocated as a treatment modality to restore teeth with a clinical crown reduced subsequent to different kinds of trauma. Multirooted teeth, however, present certain anatomic features, such as the furcation area and corresponding interradicular bone, the retromolar area, and the external oblique ridge, that may limit the possibility for soft tissue and bone reduction and minimize the effectiveness of crown-lengthening procedures. This article describes surgical modifications to overcome the anatomic difficulties that multirooted teeth present when crown lengthening is required. Furthermore, root resection is discussed as an alternative to conventional surgery when the latter is not possible.

  20. Perception of Final Lengthening.

    Science.gov (United States)

    Edwards, Jan; Beckman, Mary

    A series of phonetic production and perception experiments were designed to describe the phonological or phonetic domains of two effects in spoken English: final lengthening, generally interpreted as a mark for the edge of some linguistically-defined unit of speech production, and stress-timed shortening, generally interpreted as evidence for…

  1. Limb lengthening in Turner syndrome.

    OpenAIRE

    Noonan, K. J.; Leyes, M.; Forriol, F.

    1997-01-01

    We report the results and complications of eight consecutive patients who underwent bilateral tibial lengthenings for dwarfism associated with Turner syndrome. Lengthening was performed via distraction osteogenesis with monolateral external fixation. Tibias were lengthened an average distance of 9.2 centimeters or 33 percent of the original tibial length. The average total treatment time was 268 days. The overall complication rate was 169 percent for each tibia lengthened and each segment req...

  2. Crown lengthening procedure in the management of amelogenesis imperfecta.

    Science.gov (United States)

    Kalaivani, S; Manohar, Jenish; Shakunthala, P; Sujatha, S; Rajasekaran, S A; Karthikeyan, B; Kalaiselvan, S

    2015-08-01

    Full mouth rehabilitation includes a promising treatment planning and execution thus fulfilling esthetic, occlusal, and functional parameters maintaining the harmony of the stomatognathic system. Crown lengthening procedures have become an integral component of the esthetic armamentarium and are utilized with increasing frequency to enhance the appearance of restorations placed in the esthetic zone. Crown lengthening plays a role to create healthy relationship of the gingiva and bone levels so as to gain access to more of the tooth which can be restored, if it is badly worn, decayed or fractured, below the gum line. This paper highlights the full mouth crown lengthening procedure performed on a patient with amelogenesis imperfecta.

  3. Crown lengthening procedure in the management of amelogenesis imperfecta

    Science.gov (United States)

    Kalaivani, S.; Manohar, Jenish; Shakunthala, P.; Sujatha, S.; Rajasekaran, S. A.; Karthikeyan, B.; Kalaiselvan, S.

    2015-01-01

    Full mouth rehabilitation includes a promising treatment planning and execution thus fulfilling esthetic, occlusal, and functional parameters maintaining the harmony of the stomatognathic system. Crown lengthening procedures have become an integral component of the esthetic armamentarium and are utilized with increasing frequency to enhance the appearance of restorations placed in the esthetic zone. Crown lengthening plays a role to create healthy relationship of the gingiva and bone levels so as to gain access to more of the tooth which can be restored, if it is badly worn, decayed or fractured, below the gum line. This paper highlights the full mouth crown lengthening procedure performed on a patient with amelogenesis imperfecta. PMID:26538965

  4. The role of skeletal sonography in limb lengthening procedures.

    OpenAIRE

    Malde H; Hemmadi S; Chadda D; Parihar M; Bhosale P; Kedar R

    1993-01-01

    Eleven patients (8 males, 3 females) undergoing limb-lengthening procedures were subjected to weekly conventional radiography along with fortnightly skeletal sonography of the distraction site, to assess the rate of new bone production and complications. The radiographs were assessed for: (i) distance between the distracted bone ends, (ii) presence of new bone formation at the distraction site, (iii) regeneration of the cortical outline and (iv) overlaying soft tissue abnormality. The sonogra...

  5. Surgical lengthening of the clinical tooth crown.

    Science.gov (United States)

    Planciunas, Liudvikas; Puriene, Alina; Mackeviciene, Grazina

    2006-01-01

    To understand why the crown lengthening may be desirable, a review of periodontal anatomy is in order. The odontologists know, but often underestimate importance of periodontal tissues health to restoration of defected teeth or dental arches. In order to avoid pathological changes, to predict treatment results more precisely, it is necessary to keep gingival biological width unaltered during teeth restoration. If there are less than 2 mm from restoration's margin to marginal bone clinical crown lengthening possibility should be considered in dental treatment plan. The choice depends on relationship of crown-root-alveolar bone and esthetical expectations. In order to keep margins of restoration supragingivally the distance from marginal bone to margins of restoration should not be less than 3 mm. Ideally the margins of restoration should be supragingivally or in the same level as marginal gingiva. When the margins of restoration are prepared subgingivally, the distance from marginal gingiva to margins of restoration should not be more than 0.7 mm. To continue dental treatment in operated area is recommended not earlier than in 4 weeks, and making restorations in esthetical area--not earlier than in 6 weeks.

  6. Design of an intramedullary leg lengthening device with a shape memory actuator

    NARCIS (Netherlands)

    Aalsma, A.M.M.; Hekman, E.E.G.; Stapert, J.; Grootenboer, H.

    1999-01-01

    The procedure and the external fixator for lengthening long bones was developed by G.A. Ilizarov in the late 1960’s. This technique has, despite its proven abilities for leg lengthening and correction of angular deformities, some considerable disadvantages for the patients. Discomfort, infections an

  7. Radiographic imaging for Ilizarov limb lengthening in children

    International Nuclear Information System (INIS)

    The Ilizarov method for limb lengthening is rapidly gaining popularity in North America. Use of this new technique has necessitated modifications in radiographic protocol. Initial imaging problems gained from our experience with twenty children are detailed including accurate centering for the plain films, correcting for magnification to accurately measure the distraction gap and the expected radiographic appearance of the regenerate bone. Ultrasonography has potential value in accurately measuring the distraction gap and in imaging the new bone prior to radiographic appearance. Since overly fast distraction inhibits bone formation and overly slow distraction leads to premature consolidation, ultrasound may serve a useful role in the qualitative evaluation of new bone formation in Ilizarov limb lengthening, enabling the orthopedic surgeon to tailor the distraction rate to the particular child. (orig.)

  8. Bone lengthening after two-site osteotomy to treat massive bone and soft tissue defects of the tibia%二处截骨骨搬移治疗胫骨大段骨缺损合并软组织缺损

    Institute of Scientific and Technical Information of China (English)

    徐永清; 朱跃良; 范新宇; 丁晶; 何晓清; 王毅; 赵万秋; 简红

    2012-01-01

    Objective To explore bone lengthening after two-site osteotomy for the treatment of massive bone and soft tissue defects of the tibia. Methods From May 2009 to May 2011,we treated 6 cases of massive bone and soft tissue defects of the tibia.They were all males,aged from 20 to 51 years (average,34.5 years).Five of them were injured in a traffic accident and one was crushed by machinery.All injuries were open fractures of Gustilo type ⅢB.The soft tissue defects at the anterior leg ranged from 4 cm ×8 cm to 11 cm × 24 cm,and the tibial defects ranged from 8 to 18 cm.After debridement,the tibia was stabilized by a half-ring external fixator.Two osteotomies were made on the proximal and distal metaphyses of the tibia before bone lengthening was conducted at a speed of 1 mm/d at each osteotomy site.The bone lengthening lasted from 40 to 100 days,averaging 66.6 days. Results The 6 patients were followed up from 10 to 36 months (average,16 months).The soft tissue defects at the leg were healed and the bone defects reconstructed.Four patients obtained isometric length between the 2 legs and 2 got a length discrepancy of 1.5 cm between the 2 legs.The soft tissue defects healed after 60 to 180 days (average,103 days) and bone union was achieved after 12 to 31 months (average,19.3 months).Bone lengthening continued smoothly without nonunion or too rapid callus formation. No bone grafting was needed. Conclusion Bone lengthening after two-site osteotomy may effectively accelerate the healing of massive bone and sort tissue defects of the tibia.%目的 探讨二处截骨骨搬移治疗胫骨大段骨缺损合并软组织缺损的疗效及其加速骨和软组织愈合的可能性.方法 2009年5月至2011年5月共收治6例胫骨大段骨缺损合并软组织缺损患者,均为男性;年龄20~51岁,平均34.5岁.致伤原因:交通伤5例,机器压砸伤1例.均为Gustilo ⅢB型开放性骨折.小腿胫前软组织缺损面积为8cm ×4cm~24cm×11 cm

  9. Aesthetic Surgical Crown Lengthening Procedure

    Directory of Open Access Journals (Sweden)

    Pablo Santos de Oliveira

    2015-01-01

    Full Text Available The aim of this case report was to describe the surgical sequence of crown lengthening to apically reposition the dentogingival complex, in addition to an esthetic restorative procedure. Many different causes can be responsible for short clinical crown. In these cases, the correct execution of a restorative or prosthetic rehabilitation requires an increasing of the crown length. According to the 2003 American Academy of Periodontology (Practice Profile Survey, crown lengthening is the most habitual surgical periodontal treatment.

  10. Aesthetic Surgical Crown Lengthening Procedure.

    Science.gov (United States)

    de Oliveira, Pablo Santos; Chiarelli, Fabio; Rodrigues, José A; Shibli, Jamil A; Zizzari, Vincenzo Luca; Piattelli, Adriano; Iezzi, Giovanna; Perrotti, Vittoria

    2015-01-01

    The aim of this case report was to describe the surgical sequence of crown lengthening to apically reposition the dentogingival complex, in addition to an esthetic restorative procedure. Many different causes can be responsible for short clinical crown. In these cases, the correct execution of a restorative or prosthetic rehabilitation requires an increasing of the crown length. According to the 2003 American Academy of Periodontology (Practice Profile Survey), crown lengthening is the most habitual surgical periodontal treatment.

  11. Biologic width and crown lengthening: case reports and review.

    Science.gov (United States)

    Oh, Se-Lim

    2010-01-01

    The biologic width includes both the connective tissue attachment and the junctional epithelium and has a mean dimension of approximately 2 mm. Invading the biologic width with a restoration can result in localized crestal bone loss, gingival recession, localized gingival hyperplasia, or a combination of these three. When restoring teeth that have subgingival caries or fractures below the gingival attachment, a clinical crown-lengthening procedure is needed to establish the biologic width. This article presents three case reports that utilized crown-lengthening procedures.

  12. Limb Lengthening and Then Insertion of an Intramedullary Nail: A Case-matched Comparison

    OpenAIRE

    Rozbruch, S. Robert; Kleinman, Dawn; Fragomen, Austin T.; Ilizarov, Svetlana

    2008-01-01

    Distraction osteogenesis is an effective method for lengthening, deformity correction, and treatment of nonunions and bone defects. The classic method uses an external fixator for both distraction and consolidation leading to lengthy times in frames and there is a risk of refracture after frame removal. We suggest a new technique: lengthening and then nailing (LATN) technique in which the frame is used for gradual distraction and then a reamed intramedullary nail inserted to support the bone ...

  13. Clinical Results and Complications of Lower Limb Lengthening for Fibular Hemimelia: A Report of Eight Cases.

    Science.gov (United States)

    Mishima, Kenichi; Kitoh, Hiroshi; Iwata, Koji; Matsushita, Masaki; Nishida, Yoshihiro; Hattori, Tadashi; Ishiguro, Naoki

    2016-05-01

    Fibular hemimelia is a rare but the most common congenital long bone deficiency, encompassing a broad range of anomalies from isolated fibular hypoplasia up to substantial femoral and tibial shortening with ankle deformity and foot deficiency. Most cases of fibular hemimelia manifest clinically significant leg length discrepancy (LLD) with time that requires adequate correction by bone lengthening for stable walking. Bone lengthening procedures, especially those for pathological bones, are sometimes associated with severe complications, such as delayed consolidation, fractures, and deformities of the lengthened bones, leading to prolonged healing time and residual LLD at skeletal maturity. The purpose of this study was to review our clinical results of lower limb lengthening for fibular hemimelia.This study included 8 Japanese patients who diagnosed with fibular hemimelia from physical and radiological findings characteristic of fibular hemimelia and underwent single or staged femoral and/or tibial lengthening during growth or after skeletal maturity. LLD, state of the lengthened callus, and bone alignment were evaluated with full-length radiographs of the lower limb. Previous interventions, associated congenital anomalies, regenerate fractures were recorded with reference to medical charts and confirmed on appropriate radiographs. Successful lengthening was defined as the healing index <50 days/cm without regenerate fractures.A significant difference was observed in age at surgery between successful and unsuccessful lengthening. The incidence of regenerate fractures was significantly correlated with callus maturity before frame removal. LLD was corrected within 11 mm, whereas mechanical axis deviated laterally.Particular attention should be paid to the status of callus maturation and the mechanical axis deviation during the treatment period in fibular hemimelia. PMID:27227952

  14. Limb lengthening in Africa: tibial lengthening indicated for limb length discrepancy and postosteomyelitis pseudarthrosis

    Directory of Open Access Journals (Sweden)

    Ibrahima F

    2014-05-01

    Full Text Available Farikou Ibrahima,1,2 Pius Fokam,2 Félicien Faustin Mouafo Tambo11Department of Surgery and Specialties, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé, 2Department of Surgery, Douala General Hospital, Douala, CameroonBackground: We present a case of lengthening of a tibia to treat postosteomyelitis pseudarthrosis and limb length discrepancy by the Ilizarov device.Objective: The objective was to treat the pseudarthrosis and correct the consequent limb length discrepancy of 50 mm.Materials and methods: The patient was a 5-year-old boy. Osteotomy of the tibia, excision of fibrosis, and decortications were carried out. After a latency period of 5 days, the lengthening started at a rate of 1 mm per day.Results: The pseudarthrosis healed and the gained correction was 21.73%. The index consolidation was 49 days/cm. Minor complications were reported.Discussion: Osteomyelitis of long bones is a common poverty-related disease in Africa. The disease usually is diagnosed at an advanced stage with complications. In these conditions, treatment is much more difficult. Most surgical procedures treating this condition use the Ilizarov device. The most common reported surgical complications are refractures and recurrence of infection.Conclusion: This technique should be popularized in countries with limited resources because it would be an attractive alternative to the amputations that are sometimes performed.Keywords: Limb length discrepancy (LLD, bone gap, Ilizarov device

  15. Formation of the biologic width following crown lengthening in nonhuman primates.

    Science.gov (United States)

    Oakley, E; Rhyu, I C; Karatzas, S; Gandini-Santiago, L; Nevins, M; Caton, J

    1999-12-01

    The purpose of this study was to determine if and how the biologic width is reestablished following surgical crown lengthening. Crown-lengthening surgery was performed on the right or left maxillary and mandibular central and lateral incisors of three adult monkeys, with contralateral teeth serving as unoperated controls. Twelve weeks after surgery, tissue blocks were removed for histologic analysis. The results of a histometric evaluation indicate that the biologic width is reestablished following surgical crown lengthening. The junctional epithelium generally migrates to the apical level of root planing. Space for the supracrestal connective tissue fiber groups is created by crestal resorption of alveolar bone.

  16. Elimination of a "Gummy Smile" With Crown Lengthening and Lip Repositioning.

    Science.gov (United States)

    Mahn, Douglas H

    2016-01-01

    Excessive gingival display is considered unattractive by many patients. A combination of surgical approaches may be required to correct this problem. Clinical crown lengthening involves recontouring crestal bone levels and moving the gingival margin in an apical direction. Lip repositioning reduces gingival display by limiting upper lip movement when smiling. This article describes a case in which a combination of clinical crown lengthening and lip repositioning was used to correct excessive gingival display when smiling.

  17. Crown lengthening: a clinical review.

    Science.gov (United States)

    Talbot, T R; Briggs, P F; Gibson, M T

    1993-09-01

    The use of crown lengthening surgery as an adjunct to restorative therapy was first suggested by Rosen and Gitnick. This technique is designed to increase the clinical crown heights of teeth requiring restoration following extensive wear through attrition, abrasion and erosion. This loss of tooth tissue and resulting clinical crown height may be localized to a few teeth or affect the entire dentition. This clinical problem is reflected by the increasing number of reports of treatment of the worn dentition.

  18. [Surgical crown lengthening procedures. Preparatory step for fixed prosthesis].

    Science.gov (United States)

    Parashis, A O; Tripodakis, A P

    1990-04-01

    Necessary restorative requirements for full coverage are adequate axial wall height of the preparation for retention as well as sufficient vertical width of sound tooth structure cervically for the crown margins. In cases where adequate healthy tooth structure does not exist coronally to the epithelial attachment due to various crown damages, the margins of the crown might traumatize the periodontal attachment and the periodontium will be jeopardized iatrogenically. Teeth with inadequate axial Reight of the clinical crown, subgingival caries, vertical or horizontal fractures will require surgical crown lengthening procedures before prosthetic treatment is performed. These procedures may either involve only the soft tissues or bone remodeling as well. Irrespective of the procedure, crown lengthening must be performed with the objective of at least 3 mm. of healthy tooth structure coronally to the bone. This width will permit the formation of a new dentinogingival junction and the existence of 1-2 m.m. of sound tooth structure coronally to the new attachment line for the construction of a biologically acceptable crown margin. The purpose of this article is to discuss the clinical problem and underline the importance of crown lengthening procedures as a preparatory step for prosthetic treatment in fixed partial dentures.

  19. Surgical crown lengthening: a 12-month study - radiographic results

    Directory of Open Access Journals (Sweden)

    Daniela Eleutério Diniz

    2007-08-01

    Full Text Available OBJECTIVE: The purpose of this study was to perform a radiographic follow-up evaluation after a 12-month healing period, following crown lengthening surgery. MATERIAL AND METHODS: Twenty-three periodontally healthy subjects (mean age 32.5 years that required crown lengthening surgery in premolars were recruited. In a total of 30 premolars, full thickness flaps, osseous resection, and flap suturing were performed. The restorative margin was defined in the pre-surgical phase and maintained unaltered during the healing period, serving as a reference point. Standardized bitewing radiographs were taken before and after osseous reduction, and at 2, 3, 6, and 12-month healing periods. RESULTS: Intact lamina dura was observed at both mesial and distal alveolar crests only from the 3rd month. At 12-months, all alveolar crests presented lamina dura. The overall mean distance from the restorative margin to the alveolar crest achieved after osseous resection was 3.28±0.87 mm at mesial and 2.81±0.51 mm at distal sites. No significant radiographic changes in the bone crest were observed during a 12-month healing period. CONCLUSION: The findings of this study suggest that the radiographic proximal bone level observed on bitewing radiographs following crown lengthening surgery can be used as a reference to predict the future level of the healed alveolar crest.

  20. SURGICAL CROWN LENGTHENING: A 12-MONTH STUDY - RADIOGRAPHIC RESULTS*

    Science.gov (United States)

    Diniz, Daniela Eleutério; Okuda, Kalizia Marcela; Fonseca, Clarissa Ribeiro; Gonzalez, Marly Kimie Sonohara; Greghi, Sebastião Luiz Aguiar; do Valle, Accácio Lins; Lauris, José Roberto Pereira

    2007-01-01

    Objective The purpose of this study was to perform a radiographic follow-up evaluation after a 12-month healing period, following crown lengthening surgery. Material and methods Twenty-three periodontally healthy subjects (mean age 32.5 years) that required crown lengthening surgery in premolars were recruited. In a total of 30 premolars, full thickness flaps, osseous resection, and flap suturing were performed. The restorative margin was defined in the pre-surgical phase and maintained unaltered during the healing period, serving as a reference point. Standardized bitewing radiographs were taken before and after osseous reduction, and at 2, 3, 6, and 12-month healing periods. Results Intact lamina dura was observed at both mesial and distal alveolar crests only from the 3rd month. At 12-months, all alveolar crests presented lamina dura. The overall mean distance from the restorative margin to the alveolar crest achieved after osseous resection was 3.28±0.87 mm at mesial and 2.81±0.51 mm at distal sites. No significant radiographic changes in the bone crest were observed during a 12-month healing period. Conclusion The findings of this study suggest that the radiographic proximal bone level observed on bitewing radiographs following crown lengthening surgery can be used as a reference to predict the future level of the healed alveolar crest. PMID:19089145

  1. Biologic rationale of esthetic crown lengthening using innovative proportion gauges.

    Science.gov (United States)

    Fletcher, Paul

    2011-01-01

    Research shows that practitioners tend to underestimate the amount of tooth structure that must be exposed during a crown lengthening procedure. In the anterior portion of the mouth, this can lead to biologic width problems and subsequent cosmetic issues. This paper presents a biologically based, step-by-step approach to periodontal esthetic crown lengthening. Using a series of innovative measuring gauges, the ideal clinical crown length of a tooth as well as the proper occlusogingival placement of the interproximal papilla will be determined based on established, documented tooth proportion relationships. The biologic crown length of the tooth, defined as the distance from the incisal edge to the bone crest, will subsequently be determined as a function of the clinical crown length, with the ultimate goals being adequate tooth structure for the placement of a restorative margin, establishment of a healthy dentogingival complex, and the placement of an esthetically pleasing definitive restoration.

  2. Iliotibial band Z-lengthening.

    Science.gov (United States)

    Richards, David P; Alan Barber, F; Troop, Randal L

    2003-03-01

    Iliotibial band friction syndrome (ITBFS) is a common overuse injury reported to afflict 1.6% to 12% of runners. It results from an inflammatory response secondary to excessive friction that occurs between the lateral femoral epicondyle and the iliotibial band. Initial treatments include rest, anti-inflammatory medication, modalities (ice or heat), stretching, physical therapy, and possibly a cortisone injection. In recalcitrant cases of ITBFS, surgery has been advocated. This report describes a surgical technique of Z-lengthening of the iliotibial band in patients presenting with lateral knee pain localized to the iliotibial band at the lateral femoral epicondyle and Gerdy's tubercle who failed all nonoperative efforts.

  3. Surgical extrusion technique for clinical crown lengthening: report of three cases.

    Science.gov (United States)

    Kim, Chang-Sung; Choi, Seong-Ho; Chai, Jung-Kiu; Kim, Chong-Kwan; Cho, Kyoo-Sung

    2004-10-01

    Although a number of techniques have been proposed for clinical crown lengthening procedures, all have some limitation in terms of function and esthetics. This report presents the clinical and radiographic results of a surgical extrusion technique for clinical crown lengthening. Atraumatic surgical extrusion using a specially designed instrument (Periotome) was performed in three cases in which it was expected that extensive resective osseous surgery would have to be used for crown lengthening. Full-thickness mucoperiosteal flaps were raised both labially and palatally. The tooth was carefully luxated and extruded to the desired position without damaging the marginal bone area or root apex. No rigid splint was applied. Clinical examinations performed for more than 1 year after surgery revealed probing depths crown lengthening; it does not induce functional or esthetic deformities, especially in the anterior region.

  4. The Minimally Invasive Plate Osteosynthesis (MIPO Technique with a Locking Compression Plate for Femoral Lengthening

    Directory of Open Access Journals (Sweden)

    Tetsunaga,Tomonori

    2008-10-01

    Full Text Available A minimally invasive plate osteosynthesis technique using a locking compression plate (LCP has been used widely in trauma cases. Its advantages are that the MIPO technique does not interfere with the fracture site and thus provides improved biological healing, and that the LCP has excellent angular stability. Its use in bone lengthening, however, has not been established. In such cases, it is desirable to shorten the external skeletal fixation period as much as possible. Here, the MIPO technique using an LCP was applied to femoral distraction osteogenesis in an attempt to shorten the external skeletal fixation period. For femoral lengthening, the MIPO technique was performed in 2 stages. Orthofix external fixators (Orthofix, England were used to insert screws from the anterolateral side rather than from the lateral side of the femur for bone lengthening. When sufficient callus formation was detected postoperatively at the site of bone lengthening, and the absence of infection was ensured, limb draping was performed, including a whole external fixator, and then the MIPO technique was applied with an LCP. In 3 cases (5 limbs, the average duration of external skeletal fixation was 134days, the average external-fixation index was 24days/cm, and the average consolidation index was 22days/cm. The MIPO technique using an LCP made it possible to shorten the external skeletal fixation-wearing period in femoral lengthening.

  5. Clinical crown lengthening to improve implant results.

    Science.gov (United States)

    Kohner, J

    1992-01-01

    Clinical crown lengthening is used as an adjunct to implant procedures, and can help provide a better long-term prognosis by establishing proper occlusal planes and aiding in preparation of the abutment teeth. Crown lengthening procedures may be especially useful when caries or a fracture extends below the gingival margin, compromising impression taking and marginal fit.

  6. Crown lengthening: a surgical flap approach.

    Science.gov (United States)

    Lundergan, W; Hughes, W R

    1996-09-01

    In many instances it is not possible to place a restoration margin without encroaching on the periodontal attachment apparatus. A surgical crown-lengthening procedure can provide a good solution to this common clinical problem. This article discusses indication and contraindication for surgical crown-lengthening procedures and presents an appropriate surgical technique.

  7. Esthetic crown lengthening for maxillary anterior teeth.

    Science.gov (United States)

    Sonick, M

    1997-08-01

    In the maxillary anterior region, the gingival labial margin position is an important parameter in the achievement of an ideal smile. The relationship between the periodontium and the restoration is critical if gingival health and esthetics are to be achieved. Periodontal therapy is a necessary and useful adjunct when any anterior restoration is undertaken. Anterior surgical crown lengthening may be undertaken to avoid restorative margin impingement on the biologic width. Crown lengthening is also used to alter the gingival labial profiles. This article discusses the esthetic parameters of ideal gingival labial positions and presents a classification of crown-lengthening procedures and the procedure for a two-stage crown-lengthening technique. The two-stage crown-lengthening technique is surgically precise because healing is predictable.

  8. Three different surgical techniques of crown lengthening: A comparative study

    Directory of Open Access Journals (Sweden)

    Ramya Nethravathy

    2013-01-01

    Full Text Available Introduction: A short clinical crown may lead to poor retention form thereby leading to improper tooth preparation. Surgical crown lengthening procedure is done to increase the clinical crown length without violating the biologic width. Several techniques have been proposed for clinical crown lengthening which includes gingivectomy, apically displaced flap with or without resective osseous surgery, and surgical extrusion using periotome. Objective: The aim of this paper is to compare clinically the three different surgical techniques of crown lengthening procedures. Materials and Methods: Fifteen patients who reported to the department of Periodontology, were included in the study. Patients were randomly divided into three groups, which include patients who underwent gingivectomy (Group A, apically repositioned flap (Group B and surgical extrusion using periotome (Group C. Clinical measurements such as clinical crown length, gingival zenith, interdental papilla height were taken at baseline and at 3 rd month post-operatively. Results: Clinical and radiographic evaluation at 3 rd month suggest that surgical extrusion technique offers several advantages over the other conventional surgical techniques such as preservation of the interproximal papilla, gingival margin position and no marginal bone loss. Conclusions: This technique can be used to successfully treat a grossly damaged crown structure as a result of tooth fracture, dental caries and iatrogenic factors especially in the anterior region, where esthetics is of great concern.

  9. Crown lengthening: the periodontal-restorative connection.

    Science.gov (United States)

    Becker, W; Ochsenbein, C; Becker, B E

    1998-03-01

    Crown lengthening procedures are based on biologic principles that can be determinants for successful treatment. These procedures are fixed on an understanding of the biologic width. A few of the indications for crown lengthening are caries beneath the gingival margin, fractured teeth with insufficient clinical crown exposure, and teeth with excessive occlusal or incisal wear. This article describes flap designs, the use of a new bur probe for precise measurement of clinical crown exposure, and suturing methods for flap stabilization. Clinical documentation of patients with various clinical situations requiring crown lengthening is presented.

  10. Limited Quadricepsplasty for Contracture during Femoral Lengthening

    OpenAIRE

    Khakharia, Saurabh; Fragomen, Austin T.; Rozbruch, S. Robert

    2009-01-01

    Extension contracture of the knee is a common complication of femoral lengthening. Knee flexion exercises to stretch the contracture with physical therapy can be effective but take a prolonged amount of time to work and place increased stress across the patellofemoral joint. We developed a minimal-incision limited quadricepsplasty surgical technique to treat knee extension contracture secondary to femoral lengthening and retrospectively reviewed 16 patients treated with this procedure. The me...

  11. Clinical crown lengthening in the esthetic zone.

    Science.gov (United States)

    Camargo, Paulo M; Melnick, Philip R; Camargo, Luciano M

    2007-07-01

    Periodontal surgical procedures consisting of gingival flaps and osseous recontouring are indicated for crown lengthening of several contiguous teeth in the esthetic zone; both in cases where restorations are required and in cases where no restorations are planned, such as in patients with excessive gingival display due to altered passive eruption. Forced tooth eruption via orthodontic extrusion is the technique of choice when clinical crown lengthening is necessary on isolated teeth in the esthetic zone.

  12. Lengthening strategies for Peyronie's disease.

    Science.gov (United States)

    Gaffney, Christopher D; Pagano, Matthew J; Weinberg, Aaron C; Small, Alex C; Kuehas, Franklin E; Egydio, Paulo H; Valenzuela, Robert J

    2016-06-01

    Loss of penile length is a common complaint of men with Peyronie's disease (PD), both before and after corrective intervention, which has a significant negative effect on patient quality of life. We sought to identify and describe the methods by which penile length can be preserved or increased. We conducted an extensive, systematic literature review, based on a search of the PUBMED database for articles published between 1990 and 2015. Articles with the key words "Peyronie's disease", "penile length" and/or "penile lengthening" were reviewed if they contained subjective or objective penile length outcomes. Only English-language articles that were related to PD and penile size were included. We found no evidence in the literature that medical therapy alone increases penile length. Classic inflatable penile prosthesis (IPP) placement, plication procedures, and the Nesbit procedure appear likely to maintain or decrease penile length. Plaque incision (PI) and grafting appears likely to maintain or increase penile length, but is complicated by risk of post-operative erectile dysfunction (ED). There are several surgical procedures performed concomitantly with IPP placement that may be suitable treatment options for men with comorbid ED, and consistently increase penile length with otherwise good outcomes concerning sexual function. These include the subcoronal penile prosthesis (scIPP), Egydio circumferential technique, the sliding technique, the modified sliding technique (MoST), and the multiple slice technique (MuST). In addition, adjuvant therapies such as penile traction therapy (PTT), post-operative inflation protocols, suspensory ligament relaxation, lipectomy, and adjuvant medical therapy for glans engorgement appear to increase subjective and/or objective penile length for men at high risk of decreased penile length after PD surgery. Considering the psychological burden of length loss in men with PD, providers with adequate volume and expertise should attempt

  13. Surgical crown lengthening for function and esthetics.

    Science.gov (United States)

    Allen, E P

    1993-04-01

    Clinical crown lengthening is a useful procedure to provide tooth length for proper restoration of a tooth without compromising the periodontium or the retentive qualities of the restoration. It is also useful for enhancing maxillary anterior esthetics. Crown lengthening may be as simple as a limited removal of soft tissue or as complex as orthodontic extrusion followed by flap with osseous surgery on a tooth requiring endodontic therapy. Total treatment could thus involve endodontic, orthodontic, periodontic, and restorative procedures. Careful evaluation, case selection, treatment planning, and surgical treatment following the principles outlined in this article can achieve results that meet the functional and esthetic challenges of current dental practice.

  14. The telomere lengthening conundrum - artifact or biology?

    DEFF Research Database (Denmark)

    Steenstrup, Troels; Hjelmborg, Jacob V B; Kark, Jeremy D;

    2013-01-01

    Recent longitudinal studies of age-dependent leukocyte telomere length (LTL) attrition have reported that variable proportions of individuals experience LTL lengthening. Often, LTL lengthening has been taken at face value, and authors have speculated about the biological causation of this finding....... Based on empirical data and theoretical considerations, we show that regardless of the method used to measure telomere length (Southern blot or quantitative polymerase chain reaction-based methods), measurement error of telomere length and duration of follow-up explain almost entirely the absence of age...

  15. Cosmetic arm lengthening with monorail fixator

    Institute of Scientific and Technical Information of China (English)

    Hemendra Kumar Agrawal; Balvinder Singh; Mohit Garg; Vipin Khatkar; Sumit Batra; Vinod Kumar Sharma

    2015-01-01

    Upper limb length discrepancy is a rare occurrence.Humerus shortening may need specialized treatment to restore the functional and cosmetic status of upper limb.We report a case of humerus lengthening of 9 cm with a monorail external fixator and the result was observed during a 2-year follow-up.Humerus lengthening needs specialized focus as it is not only a cosmetic issue but also a functional demand.The monorail unilateral fixator is more functional and cosmetically acceptable,and thus becomes an effective treatment option.

  16. Bone

    Science.gov (United States)

    Helmberger, Thomas K.; Hoffmann, Ralf-Thorsten

    The typical clinical signs in bone tumours are pain, destruction and destabilization, immobilization, neurologic deficits, and finally functional impairment. Primary malignant bone tumours are a rare entity, accounting for about 0.2% of all malignancies. Also benign primary bone tumours are in total rare and mostly asymptomatic. The most common symptomatic benign bone tumour is osteoid osteoma with an incidence of 1:2000.

  17. Precise and feasible measurements of lateral calcaneal lengthening osteotomies by radiostereometric analysis in cadaver feet

    Science.gov (United States)

    Martinkevich, P.; Rahbek, O.; Møller-Madsen, B.; Søballe, K.; Stilling, M.

    2015-01-01

    Objectives Lengthening osteotomies of the calcaneus in children are in general grafted with bone from the iliac crest. Artificial bone grafts have been introduced, however, their structural and clinical durability has not been documented. Radiostereometric analysis (RSA) is a very accurate and precise method for measurements of rigid body movements including the evaluation of joint implant and fracture stability, however, RSA has not previously been used in clinical studies of calcaneal osteotomies. We assessed the precision of RSA as a measurement tool in a lateral calcaneal lengthening osteotomy (LCLO). Methods LCLO was performed in six fixed adult cadaver feet. Tantalum markers were inserted on each side of the osteotomy and in the cuboideum. Lengthening was done with a plexiglas wedge. A total of 24 radiological double examinations were obtained. Two feet were excluded due to loose and poorly dispersed markers. Precision was assessed as systematic bias and 95% repeatability limits. Results Systematic bias was generally below 0.10 mm for translations. Precision of migration measurements was below 0.2 mm for translations in the osteotomy. Conclusion RSA is a precise tool for the evaluation of stability in LCLO. Cite this article: Bone Joint Res 2015;4:78–83. PMID:25957380

  18. Bone

    International Nuclear Information System (INIS)

    Bone scanning provides information on the extent of primary bone tumors, on possible metastatic disease, on the presence of osteomyelitis prior to observation of roentgenographic changes so that earlier therapy is possible, on the presence of collagen diseases, on the presence of fractures not disclosed by x-ray films, and on the evaluation of aseptic necrosis. However, the total effect and contribution of bone scanning to the diagnosis, treatment, and ultimate prognosis of pediatric skeletal diseases is, as yet, unknown. (auth)

  19. Lengthening over nails using the double plate system ONAS-DPS.

    Science.gov (United States)

    Antolič, Vane

    2016-01-01

    Stable insertion of large Schanz screws behind an intramedullary (IM) nail when lengthening over nails (LON) may be difficult due to the limited bone stock. Additionally, the highly probable contact between the screws and IM nail (which is difficult to avoid) increases the likelihood of infection spreading from the skin via Schanz screws directly to the IM nail. A new device for LON has been developed. Instead of inserting Schanz screws from the external fixator beside the IM nail (as in standard LON), a system of two overlaying plates was constructed. Schanz screws can be fixed to the plates without entering the bone. The plates are fixed to the bone using four angle stability screws. The holes in the plates offer stabile fixation for a chosen angle under which the screw is positioned through the cortical bone. Using the new system there is no need to place Schanz screws behind the IM nail. Instead, Schanz screws pass to the plate and not through the bone. The new system for elongation over IM nail is called "Over Nail Angle Stability-Double Plate System" (ONAS-DPS) [Antolič V (2013) Modular side device with an intramedullary nail for guiding a bone during its lengthening. World Intellectual Property Organization. International Publication number: WO 2013/176632 A1]. PMID:27163094

  20. Lengthening over nails using the double plate system ONAS-DPS

    Directory of Open Access Journals (Sweden)

    Antolič Vane

    2016-01-01

    Full Text Available Stable insertion of large Schanz screws behind an intramedullary (IM nail when lengthening over nails (LON may be difficult due to the limited bone stock. Additionally, the highly probable contact between the screws and IM nail (which is difficult to avoid increases the likelihood of infection spreading from the skin via Schanz screws directly to the IM nail. A new device for LON has been developed. Instead of inserting Schanz screws from the external fixator beside the IM nail (as in standard LON, a system of two overlaying plates was constructed. Schanz screws can be fixed to the plates without entering the bone. The plates are fixed to the bone using four angle stability screws. The holes in the plates offer stabile fixation for a chosen angle under which the screw is positioned through the cortical bone. Using the new system there is no need to place Schanz screws behind the IM nail. Instead, Schanz screws pass to the plate and not through the bone. The new system for elongation over IM nail is called “Over Nail Angle Stability-Double Plate System” (ONAS-DPS [Antolič V (2013 Modular side device with an intramedullary nail for guiding a bone during its lengthening. World Intellectual Property Organization. International Publication number: WO 2013/176632 A1].

  1. Crown lengthening: basic principles, indications, techniques and clinical case reports.

    Science.gov (United States)

    Yeh, Simon; Andreana, Sebastiano

    2004-11-01

    Sometimes, in order to properly restore teeth, surgical intervention in the form of a crown-lengthening procedure is required. Crown lengthening is a periodontal resective procedure, aimed at removing supporting periodontal structures to gain sound tooth structure above the alveolar crest level. Periodontal health is of paramount importance for all teeth, both sound and restored. For the restorative dentist to utilize crown lengthening, it is important to understand the concept of biologic width, indications, techniques and other principles. This article reviews these basic concepts of clinical crown lengthening and presents four clinical cases utilizing crown lengthening as an integral part of treatments, to restore teeth and their surrounding tissues to health.

  2. ATRX represses alternative lengthening of telomeres

    OpenAIRE

    Napier, Christine E.; Huschtscha, Lily I.; Harvey, Adam; Bower, Kylie; Noble, Jane R.; Hendrickson, Eric A.; Reddel, Roger R

    2015-01-01

    The unlimited proliferation of cancer cells requires a mechanism to prevent telomere shortening. Alternative Lengthening of Telomeres (ALT) is an homologous recombination-mediated mechanism of telomere elongation used in tumors, including osteosarcomas, soft tissue sarcoma subtypes, and glial brain tumors. Mutations in the ATRX/DAXX chromatin remodeling complex have been reported in tumors and cell lines that use the ALT mechanism, suggesting that ATRX may be an ALT repressor. We show here th...

  3. Evaluation of the Effect of Surgical Crown Lengthening on Periodontal Parameters

    Directory of Open Access Journals (Sweden)

    Farzane Vaziri

    2015-09-01

    Full Text Available Background: Surgical crown lengthening is needed for teeth with subgingival caries, fractured teeth, insufficient crown length, and deep subgingival margin of failed restorations. Since there is no agreement on the effects of crown lengthening surgery on gingival parameters, the purpose of this study was to evaluate periodontal parameters in patients who needed crown lengthening surgery. Methods: Twenty patients who had healthy periodontium and needed surgical crown lengthening were included in this study. After professional dental cleaning, gingival parameters including gingival index (GI, probing depth (PD, bone level (BL, and transsulcular probing (TSP were recorded in interproximal and keratinized gingiva (KG in mid buccal portion. The patients were evaluated one and three months after the surgery. Results: After one and three months of the surgery, the amount of PD reduced from 2.32 mm to 1.25 mm and 1.17 mm, respectively (P=0.001. The mean of BL reduction was 0.88 mm after one month (P=0.001, but there was no reduction between 1 month and 3 months. Amounts of KG at baseline andone month later were 4.2 mm and 2.9 mm, respectively (P=0.001, and remained at the same level up to three months. TSP significantly reduced (from 3.67 mm at baseline to 2.62 mm after 1 month, and to 2.27 mm after 3 months (P=0.001, P=0.005. Conclusion: The present  study suggests that in the presence of good oral hygiene, except BW (biological width, other parameters including PD, BL, KG, and TSP had significant changes after crown lengthening surgery in the period of 1 month and 3 months (P

  4. Guided esthetic crown lengthening: case reports.

    Science.gov (United States)

    Borges, Ivan; Ribas, Tania Rocha Cabral; Duarte, Poliana Mendes

    2009-01-01

    It is well-recognized that excessive gingival display can have a negative impact on a patient's smile. Excessive gingival display due to gingival enlargement or altered passive eruption (dentogingival cause) can be corrected effectively through periodontal surgeries. This article describes two successful esthetic crown-lengthening surgeries that were guided by an acetate template to better predict the outcomes of the surgical procedures in relation to the symmetry and harmony of the gingival contour. This article also highlights the importance of utilizing an interdisciplinary approach to obtain an optimum esthetic result for restorative treatments in the anterior maxilla.

  5. Physeal growth arrest after tibial lengthening in achondroplasia

    Science.gov (United States)

    2012-01-01

    Background and purpose Bilateral tibial lengthening has become one of the standard treatments for upper segment-lower segment disproportion and to improve quality of life in achondroplasia. We determined the effect of tibial lengthening on the tibial physis and compared tibial growth that occurred at the physis with that in non-operated patients with acondroplasia. Methods We performed a retrospective analysis of serial radiographs until skeletal maturity in 23 achondroplasia patients who underwent bilateral tibial lengthening before skeletal maturity (lengthening group L) and 12 achondroplasia patients of similar height and age who did not undergo tibial lengthening (control group C). The mean amount of lengthening of tibia in group L was 9.2 cm (lengthening percentage: 60%) and the mean age at the time of lengthening was 8.2 years. The mean duration of follow-up was 9.8 years. Results Skeletal maturity (fusion of physis) occurred at 15.2 years in group L and at 16.0 years in group C. The actual length of tibia (without distraction) at skeletal maturity was 238 mm in group L and 277 mm in group C (p = 0.03). The mean growth rates showed a decrease in group L relative to group C from about 2 years after surgery. Physeal closure was most pronounced on the anterolateral proximal tibial physis, with relative preservation of the distal physis. Interpretation Our findings indicate that physeal growth rate can be disturbed after tibial lengthening in achondroplasia, and a close watch should be kept for such an occurrence—especially when lengthening of more than 50% is attempted. PMID:22489887

  6. Impact of pedicle-lengthening osteotomy on spinal canal volume and neural foramen size in three types of lumbar spinal stenosis

    Science.gov (United States)

    Li, P.; Qian, L.; Wu, W. D.; Wu, C. F.

    2016-01-01

    Objectives Pedicle-lengthening osteotomy is a novel surgery for lumbar spinal stenosis (LSS), which achieves substantial enlargement of the spinal canal by expansion of the bilateral pedicle osteotomy sites. Few studies have evaluated the impact of this new surgery on spinal canal volume (SCV) and neural foramen dimension (NFD) in three different types of LSS patients. Methods CT scans were performed on 36 LSS patients (12 central canal stenosis (CCS), 12 lateral recess stenosis (LRS), and 12 foraminal stenosis (FS)) at L4-L5, and on 12 normal (control) subjects. Mimics 14.01 workstation was used to reconstruct 3D models of the L4-L5 vertebrae and discs. SCV and NFD were measured after 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm pedicle-lengthening osteotomies at L4 and/or L5. One-way analysis of variance was used to examine between-group differences. Results In the intact state, SVC and NFD were significantly larger in the control group compared with the LSS groups (PCCS>FS>Control. After lengthening at L5 and L4-L5, the percentage increase in SCV (per millimetre) was LRS>FS>CCS>Control. After lengthening at L4 and L4-L5, the percentage increase in NFD (per millimetre) was FS>CCS>LRS>Control. After lengthening at L5, the percentage increase in NFD (per millimetre) was CCS>LRS>control>FS. Conclusions LRS patients are the most suitable candidates for treatment with pedicle-lengthening osteotomy. Lengthening L4 pedicles produced larger percentage increases in NFD than lengthening L5 pedicles (p lumbar spinal stenosis. Bone Joint Res 2016;5:239–246. DOI: 10.1302/2046-3758.56.2000469. PMID:27340140

  7. ATRX represses alternative lengthening of telomeres.

    Science.gov (United States)

    Napier, Christine E; Huschtscha, Lily I; Harvey, Adam; Bower, Kylie; Noble, Jane R; Hendrickson, Eric A; Reddel, Roger R

    2015-06-30

    The unlimited proliferation of cancer cells requires a mechanism to prevent telomere shortening. Alternative Lengthening of Telomeres (ALT) is an homologous recombination-mediated mechanism of telomere elongation used in tumors, including osteosarcomas, soft tissue sarcoma subtypes, and glial brain tumors. Mutations in the ATRX/DAXX chromatin remodeling complex have been reported in tumors and cell lines that use the ALT mechanism, suggesting that ATRX may be an ALT repressor. We show here that knockout or knockdown of ATRX in mortal cells or immortal telomerase-positive cells is insufficient to activate ALT. Notably, however, in SV40-transformed mortal fibroblasts ATRX loss results in either a significant increase in the proportion of cell lines activating ALT (instead of telomerase) or in a significant decrease in the time prior to ALT activation. These data indicate that loss of ATRX function cooperates with one or more as-yet unidentified genetic or epigenetic alterations to activate ALT. Moreover, transient ATRX expression in ALT-positive/ATRX-negative cells represses ALT activity. These data provide the first direct, functional evidence that ATRX represses ALT. PMID:26001292

  8. Surgical crown lengthening: a periodontal and restorative interdisciplinary approach.

    Science.gov (United States)

    Parwani, Simran R; Parwani, Rajkumar N

    2014-01-01

    Surgical crown lengthening helps to provide an adequate retention form for proper tooth preparation, thus enabling dentists to create esthetically pleasing and healthy restorations. Long-term stability requires accurate diagnosis and development of a comprehensive treatment plan in each case. This sequence of events stresses the importance of communication between the restorative dentist and the periodontist. This article presents 2 cases that involve surgical crown lengthening (including mucoperiosteal flap and ostectomy) for the restoration of teeth.

  9. Alternative lengthening of telomeres in normal mammalian somatic cells

    OpenAIRE

    Neumann, Axel A.; Watson, Catherine M.; Noble, Jane R.; Hilda A Pickett; Tam, Patrick P.L.; Reddel, Roger R

    2013-01-01

    Alternative lengthening of telomeres (ALT), a mechanism involving the replication of new telomeric DNA from a DNA template, is used by some cancer cells to lengthen their telomeres. Reddel and colleagues now show that ALT activity exists in normal somatic tissues as well. A telomere with a DNA tag is found to be intertelomerically copied in normal somatic cells but not germline cells, providing important implications for understanding telomere maintenance and its evolution.

  10. Physeal growth arrest after tibial lengthening in achondroplasia

    OpenAIRE

    Song, Sang-Heon; Agashe, Mandar Vikas; Huh, Young-Jae; Hwang, Soon-Young; Song, Hae-Ryong

    2012-01-01

    Background and purpose Bilateral tibial lengthening has become one of the standard treatments for upper segment-lower segment disproportion and to improve quality of life in achondroplasia. We determined the effect of tibial lengthening on the tibial physis and compared tibial growth that occurred at the physis with that in non-operated patients with acondroplasia. Methods We performed a retrospective analysis of serial radiographs until skeletal maturity in 23 achondroplasia patients who und...

  11. Evaluation of cephalometric points in midface bone lengthening with the use of a rigid external device in syndromic craniosynostosis patients Avaliação de pontos cefalométricos no alongamento ósseo do terço médio da face em portadores de craniossinostose sindrômica com a utilização de dispositivo externo rígido

    Directory of Open Access Journals (Sweden)

    Daniel Santos Corrêa Lima

    2009-06-01

    Full Text Available Distraction osteogenesis has been extensively used to correct severe midface hypoplasia in syndromic craniosynostosis patients. However few studies have reported midface distraction outcomes through cephalometric evaluation. AIM: The purpose of the present study was to evaluate outcomes with midface distraction rigid external device (RED in patients with syndromic craniosynostosis, in terms of quantity of bone lengthening, skeletal stability and facial growth. MATERIALS AND METHODS: Eleven patients were retrospectively evaluated in this study. Cephalometrics was carried out through three teleradiographies from each patient (T1 -before surgery; T2- immediate postop, rigth after distractor removal; T3 - late postop, obtained with a minimal interval of 12 months after surgery. RESULTS: Significant midface advancement was achieved with the procedure. The rate of horizontal relapse was minimal. We noticed a clear vertical facial growth, contrary to what was seen in the horizontal aspect, when there was a mild posterior relapse and no growth evidence. CONCLUSION: Cephalometric evaluation showed adequate results in midface bone lengthening with rigid external distractor.A distração osteogênica tem sido extensamente empregada na correção da grave hipoplasia do terço médio da face de portadores de craniossinostose sindrômica. Poucos estudos têm apresentado os resultados da distração do terço médio da face através de avaliação cefalométrica. OBJETIVO: O objetivo do estudo foi o de avaliar os resultados obtidos com o avanço ósseo do terço médio da face seguida da utilização de dispositivo rígido externo de distração (RED, em portadores de craniossinostose sindrômica, através de análise cefalométrica. MATERIAL E MÉTODOS: O estudo teve desenho retrospectivo, onde onze pacientes foram avaliados retrospectivamente. A análise cefalométrica foi realizada a partir de três telerradiografias de cada paciente (T1- préoperatório; T

  12. The Accordion Maneuver: A Noninvasive Strategy for Absent or Delayed Callus Formation in Cases of Limb Lengthening

    Directory of Open Access Journals (Sweden)

    Asim M. Makhdom

    2015-01-01

    Full Text Available The distraction osteogenesis (DO technique has been used worldwide to treat many orthopaedic conditions. Although successful, absent or delayed callus formation in the distraction gap can lead to significant morbidities. An alternate cycle of distraction-compression (accordion maneuver is one approach to accelerate bone regeneration. The primary aim of our study is to report our experience with the accordion maneuver during DO and to provide a detailed description of this technique, as performed in our center. The secondary aim is to present a review of the literature regarding the use of accordion maneuver. We reviewed the database of all patients undergoing limb lengthening from the year of 1997 to 2012. Four patients (6.15% out of 65 showed poor bone regenerate in their tibiae and therefore accordion maneuver was applied for a mean of 6.75 weeks. Of these, three patients have had successful outcome with this technique. The literature showed that this technique is successful approach to trigger bone healing. However, details of how and when to apply this combination of distraction-compression forces were lacking. In conclusion, the accordion technique is safe noninvasive approach to promote bone formation, thus avoiding more invasive surgical procedures in cases of poor callus formation in limb lengthening.

  13. Laser-assisted flapless crown lengthening: a case series.

    Science.gov (United States)

    McGuire, Michael K; Scheyer, E Todd

    2011-01-01

    As part of the paradigm shift toward more minimally invasive surgical procedures, increasing numbers of references to laser-mediated flapless crown lengthening are noted in the published literature. The vast majority of these references are noncontrolled case reports or technique-focused articles. Therefore, prospective, randomized controlled studies that objectively examine the safety and efficacy of flapless crown lengthening are lacking. The current case series represents an initial attempt to examine some of the clinical issues posed by this minimally invasive flapless approach. Ultimately, only well-designed controlled clinical trials can yield the type of evidence-based data necessary to categorize this approach to crown lengthening as standard-of-care treatment.

  14. On the Effect of Lengthening Circadian Rhythm by Heavy Water

    Directory of Open Access Journals (Sweden)

    Akhmedov T. R.

    2014-01-01

    Full Text Available The problem of time sensor of biological clock (BC attracts interest of many scientists, and a great number of experiments are being conducted to stud y the influence of vari- ous physical and chemical factors on functioning of BC. Special attention is drawn to studying the influence of heavy water (D 2 O on functioning of BC that always leads to lengthening of circadian rhythms (CR. This work presents theoretical consideration of lengthening of CR, when hydrogen (H 2 in water is replaced by deuterium (D 2 , that is based on spacial difference of energy levels with similar principle quantum numbers.

  15. An Update on Crown Lengthening. Part 2: Increasing Clinical Crown Height to Facilitate Predictable Restorations.

    Science.gov (United States)

    Kalsi, Harpoonam Jeet; Bomfim, Deborah Iola; Darbar, Ulpee

    2015-04-01

    This is the second paper in this two-part series. Paper one provided an overview of managing gingival tissue excess and paper two will focus on increasing clinical crown height to facilitate restorative treatment. Crown lengthening is a surgical procedure aimed at the removal of gingival tissue with or without adjunctive bone removal. The different types of procedure undertaken will be discussed over the two papers. In order to provide predictable restorations, care must be taken to ensure the integrity of the margins. If this is not taken into account it can lead to an impingement on the biologic width, which may in turn lead to chronic inflammation resulting in recession or the development of periodontal problems which can be hard to manage. Clinical Relevance: This paper aims to reinforce the need for thorough diagnosis and treatment planning and provides an overview of the various procedures that can be undertaken.

  16. Analysis of callus pattern of tibia lengthening in achondroplasia and a novel method of regeneration assessment using pixel values

    International Nuclear Information System (INIS)

    To relate morphology of new bone formation to outcome after tibial lengthening performed in patients with achondroplasia. A retrospective analysis of 60 tibial segments in 30 achondroplasia patients was performed. There were 22 female patients and eight male patients, with a mean age of 9.8 years. New bone formation was classified by shape, homogeneity and density. Pixel values in relation to original bone were measured using a picture-archiving communication system (PACS). Clinical outcome was described by the external fixator and maturation indices. Mean lengthening was 9.2 cm (range 3-12.7 cm). The mean external fixator index was 23.4 (range 15.1-50). The mean maturation index was 12.3 days/cm (range 6-40 days/cm). Homogeneous pathways were associated with the best clinical results (fixator index 20.4, maturation index 10.8), followed by heterogeneous pathway (external fixator index 26.5, maturation index 16.8) and radiolucent pathway (fixator index 31.2, maturation index 21.4). Both cylindrical (external fixator index 25.2, maturation index 14.5) and concave (external fixator index 26.6, maturation index 16.3) callus shapes were favourable. Mineralization of new bone became equal to that of normal bone within 16 weeks (mean) for homogeneous pathway, 12 weeks for heterogeneous pathway and 32 weeks for lucent pathway. The type of new bone formation seen on radiographs is related to clinical outcome, with homogeneous pathways being the most favourable ones. (orig.)

  17. Impact of leg lengthening on viscoelastic properties of the deep fascia

    OpenAIRE

    Wu Zi-Xiang; Wei Yi-Yong; Wang Hai-Qiang; Luo Zhuo-Jing

    2009-01-01

    Abstract Background Despite the morphological alterations of the deep fascia subjected to leg lengthening have been investigated in cellular and extracellular aspects, the impact of leg lengthening on viscoelastic properties of the deep fascia remains largely unknown. This study aimed to address the changes of viscoelastic properties of the deep fascia during leg lengthening using uniaxial tensile test. Methods Animal model of leg lengthening was established in New Zealand white rabbits. Dist...

  18. Stretching skeletal muscle: chronic muscle lengthening through sarcomerogenesis.

    Directory of Open Access Journals (Sweden)

    Alexander M Zöllner

    Full Text Available Skeletal muscle responds to passive overstretch through sarcomerogenesis, the creation and serial deposition of new sarcomere units. Sarcomerogenesis is critical to muscle function: It gradually re-positions the muscle back into its optimal operating regime. Animal models of immobilization, limb lengthening, and tendon transfer have provided significant insight into muscle adaptation in vivo. Yet, to date, there is no mathematical model that allows us to predict how skeletal muscle adapts to mechanical stretch in silico. Here we propose a novel mechanistic model for chronic longitudinal muscle growth in response to passive mechanical stretch. We characterize growth through a single scalar-valued internal variable, the serial sarcomere number. Sarcomerogenesis, the evolution of this variable, is driven by the elastic mechanical stretch. To analyze realistic three-dimensional muscle geometries, we embed our model into a nonlinear finite element framework. In a chronic limb lengthening study with a muscle stretch of 1.14, the model predicts an acute sarcomere lengthening from 3.09[Formula: see text]m to 3.51[Formula: see text]m, and a chronic gradual return to the initial sarcomere length within two weeks. Compared to the experiment, the acute model error was 0.00% by design of the model; the chronic model error was 2.13%, which lies within the rage of the experimental standard deviation. Our model explains, from a mechanistic point of view, why gradual multi-step muscle lengthening is less invasive than single-step lengthening. It also explains regional variations in sarcomere length, shorter close to and longer away from the muscle-tendon interface. Once calibrated with a richer data set, our model may help surgeons to prevent muscle overstretch and make informed decisions about optimal stretch increments, stretch timing, and stretch amplitudes. We anticipate our study to open new avenues in orthopedic and reconstructive surgery and enhance

  19. Engineering of a functional bone organ through endochondral ossification

    OpenAIRE

    Scotti, Celeste; Piccinini, Elia; Takizawa, Hitoshi; Todorov, Atanas; Bourgine, Paul; Papadimitropoulos, Adam; Barbero, Andrea; Manz, Markus G.; Martin, Ivan

    2013-01-01

    Embryonic development, lengthening, and repair of most bones proceed by endochondral ossification, namely through formation of a cartilage intermediate. It was previously demonstrated that adult human bone marrow-derived mesenchymal stem/stromal cells (hMSCs) can execute an endochondral program and ectopically generate mature bone. Here we hypothesized that hMSCs pushed through endochondral ossification can engineer a scaled-up ossicle with features of a “bone organ,” including physiologicall...

  20. A new flapless technique for crown lengthening after orthodontic extrusion.

    Science.gov (United States)

    Braga, Giovanni; Bocchieri, Anna

    2012-02-01

    Orthodontic extrusion (OE), which is performed in many different clinical situations to move a tooth or its periodontal tissues coronally, is often associated with supracrestal fiberotomy and root planing (OEFRP) or followed by surgical crown lengthening. The OEFRP procedure must be carried out every 2 weeks during the entire extrusive orthodontic phase, and precise control of the technique itself can be quite difficult, especially when this approach is to be performed on a limited portion of the root perimeter in teeth affected by angular defects. The aim of this study was to show a new nonsurgical crown-lengthening technique, performed shortly after the completion of OE, to simultaneously achieve proper hard and soft tissue architecture. Three different illustrative situations (periodontal pocket, root fracture, and root perforation) are described.

  1. Femoral Lengthening by Ilizarov Technique: Results and Complications

    Directory of Open Access Journals (Sweden)

    Altaf A. Kawoosa, Suhail Majid, Manzoor A. Halwai, Mohd. Ramzan Mir, G.R. Mir

    2004-07-01

    Full Text Available Femoral lengthening using Ilizarov technique was performed in ten patients comprising of 6 femalesand 4 males in an age group of 10-19 years with an average shortening of 6.8 cms. The etiology ofshortening was post-infective in 8 patients and post-traumatic in two patients. The desired lengthwas achieved in six patients and in four patients the final limb length discrepancy ranged between 1to 3 cms. The total duration of external fixation ranged from 24 weeks to 90 weeks with an averagehealing index of 6.23 weeks/cm. There were 10 problems and 2 true complications. Temporarydecrease in knee range of motion was a common difficulty encountered during lengthening. Resultswere rated as excellent in five, good in two, fair in two and poor in one patient.

  2. Alternative lengthening of telomeres: remodeling the telomere architecture

    OpenAIRE

    Conomos, Dimitri; Hilda A Pickett; Reddel, Roger R

    2013-01-01

    To escape from the normal limits on proliferative potential, cancer cells must employ a means to counteract the gradual telomere attrition that accompanies semi-conservative DNA replication. While the majority of human cancers do this by up-regulating telomerase enzyme activity, most of the remainder use a homologous recombination-mediated mechanism of telomere elongation known as alternative lengthening of telomeres (ALT). Many molecular details of the ALT pathway are unknown, and even less ...

  3. Detection of alternative lengthening of telomeres by telomere quantitative PCR

    OpenAIRE

    Lau, Loretta M. S.; Dagg, Rebecca A.; Henson, Jeremy D.; Au, Amy Y.M.; Royds, Janice A; Reddel, Roger R

    2012-01-01

    Alternative lengthening of telomeres (ALT) is one of the two known telomere length maintenance mechanisms that are essential for the unlimited proliferation potential of cancer cells. Existing methods for detecting ALT in tumors require substantial amounts of tumor material and are labor intensive, making it difficult to study prevalence and prognostic significance of ALT in large tumor cohorts. Here, we present a novel strategy utilizing telomere quantitative PCR to diagnose ALT. The protoco...

  4. Slide crown lengthening procedure using wide surface incisions and cyanoacrylate.

    Science.gov (United States)

    Szymaitis, Dennis W

    2011-01-01

    This article introduces the slide crown lengthening procedure (SCLP), which incorporates surgical design features to overcome present crown lengthening procedure (CLP) shortcomings. The result is a 75% decrease in required surgery on adjacent teeth and a corresponding 75% reduction in surgical time. Other advantages include a reduction in surgical morbidity, improvement in terminal esthetics, and fewer teeth subject to papillae removal and apically repositioned gingiva. The 20 to 30 degree incision forming the slide is the pivotal feature; it allows effortless flap positioning. This incision angle enables wide surface incisions to adhere flaps together by producing stronger fibrin clots, decreasing tissue retraction angles, and reforming disrupted fibrin clots as incision sides slide while maintaining contact. This enhanced fibrin clot eliminates the need for sutures. The slide produced by the 20 to 30 degree incision functions for crown lengthening on all sites (facial, lingual, or palatal). This versatile surgical design introduces a new healing dimension that adapts to and provides benefits for other dental surgeries, such as gingival grafts, endodontic surgery, implants, and extractions.

  5. 牙冠延长术的临床应用%Clinical application of crown lengthening surgery

    Institute of Scientific and Technical Information of China (English)

    付兆江; 韩晓红

    2012-01-01

    牙冠延长术是近年来临床研究和推广的热门课题.临床上经常遇到因龋病、冠折等原因造成龈上牙体组织过短,给冠修复带来困难;如果冠边缘延伸至龈下过深,侵犯了生物学宽度,则易引起牙周问题.牙冠延长术利用生物学宽度的原理,应用翻瓣术联合牙槽骨修整的方法,延长牙冠或暴露龈下的牙体断端,其重点在于切除牙龈的同时,去除部分牙槽骨,以便在更根方的位置重建健康的牙周组织.%Crown lengthening surgery is a hot topic in clinic research. We often encountere too short teeth structures caused by caries or crown fracture. If the denture crown margin violate the biologic width periodontal problems will occur. Crown lengthening surgery, abide by the principle of biological width, using flap surgery combined with alveolar bone trimming can extend crown or expose the subgingival teeth structure by removing part of the alveolar bone and gum so as to reestablish healthy periodontal tissue in apical direction.

  6. Safety and efficacy of botox injection in alleviating post-operative pain and improving quality of life in lower extremity limb lengthening and deformity correction

    Directory of Open Access Journals (Sweden)

    Finley Allen

    2007-09-01

    Full Text Available Abstract Background Distraction osteogenesis is the standard treatment for the management of lower limb length discrepancy of more than 3 cm and bone loss secondary to congenital anomalies, trauma or infection. This technique consists of an osteotomy of the bone to be lengthened, application of an external fixator, followed by gradual and controlled distraction of the bone ends. Although limb lengthening using the Ilizarov distraction osteogenesis principle yields excellent results in most cases, the technique has numerous problems and is not well tolerated by many children. The objective of the current study is to determine if Botulinum Toxin A (BTX-A, which is known to possess both analgesic and paralytic actions, can be used to alleviate post-operative pain and improve the functional outcome of children undergoing distraction osteogenesis. Methods/Design The study design consists of a multi centre, randomized, double-blinded, placebo-controlled trial. Patients between ages 5–21 years requiring limb lengthening or deformity correction using distraction will be recruited from 6 different sites (Shriners Hospital for Children in Montreal, Honolulu, Philadelphia and Portland as well as DuPont Hospital for Children in Wilmington, Delaware and Hospital for Sick Children in Toronto, Ont. Approximately 150 subjects will be recruited over 2 years and will be randomized to either receive 10 units per Kg of BTX-A or normal saline (control group intraoperatively following the surgery. Functional outcome effects will be assessed using pain scores, medication dosages, range of motion, flexibility, strength, mobility function and quality of life of the patient. IRB approval was obtained from all sites and adverse reactions will be monitored vigorously and reported to IRB, FDA and Health Canada. Discussion BTX-A injection has been widely used world wide with no major side effects reported. However, to the best of our knowledge, this is the first time BTX

  7. Clinical evaluation of the biological width following surgical crown-lengthening procedure: A prospective study

    Directory of Open Access Journals (Sweden)

    Shobha K

    2010-01-01

    Full Text Available Background and Objectives: The purpose of this study was to evaluate the positional changes of the periodontal tissues, particularly the biological width, following surgical crown-lengthening in human subjects. Materials and Methods: A clinical trial study involving 15 patients was carried out for a period of 6 months. Sites were divided into 3 groups: treated (TT sites, adjacent (AD sites and nonadjacent (NAD sites. Free gingival margin [FGM], attachment level, pocket depth, bone level, biological width [BW] were recorded at baseline, 1, 3 and 6 months. Direct bone level after flap reflection was recorded before and after osseous resection at baseline only. Level of osseous crest was lowered based on BW, and supracrestal tooth structure needed using a combination of rotary and hand instruments. Statistical Analysis: Student t test and ANOVA were used. Results: Overall, apical displacement of FGM at TT, AD and NAD sites was statistically significant compared to baseline. The apical displacement of FGM at TT site was more when compared to that at AD and NAD sites at 3 and 6 months. The BW at the TT site was smaller at 1, 3 and 6 months compared to that at baseline. However, at all sites, BW was reestablished to the baseline value at the end of 6 months. Interpretation and Conclusion: The BW at TT sites was reestablished to its original vertical dimension by 6 months. In addition, a consistent 2-mm gain of coronal tooth structure was observed at the 1, 3 and 6-month examinations.

  8. Alternative lengthening of telomeres and loss of ATRX are frequent events in pleomorphic and dedifferentiated liposarcomas.

    Science.gov (United States)

    Lee, Jen-Chieh; Jeng, Yung-Ming; Liau, Jau-Yu; Tsai, Jia-Huei; Hsu, Hung-Han; Yang, Ching-Yao

    2015-08-01

    Telomerase activation and alternative lengthening of telomeres are two major mechanisms of telomere length maintenance. Soft tissue sarcomas appear to use the alternative lengthening of telomeres more frequently. Loss of α-thalassemia/mental retardation syndrome X-linked (ATRX) or death domain-associated protein 6 (DAXX) expression has been implicated in the pathogenesis of alternative telomere lengthening in pancreatic endocrine neoplasm and glioma. The mechanism leading to the alternative lengthening of telomeres in liposarcoma remains unknown. Whereas alternative telomere lengthening was determined to be an indicator of poor prognosis in liposarcomas as a whole, its prognostic power has not been verified in any subtype of liposarcoma. In this study, we characterized the status of alternative telomere lengthening and expression of ATRX and DAXX in 111 liposarcomas (28 well-differentiated, 52 dedifferentiated, 20 myxoid or round cell, and 11 pleomorphic liposarcomas) by telomere fluorescence in situ hybridization and immunohistochemistry, respectively. Alternative lengthening of telomere was observed in 0% (0/16) of well-differentiated, 30% (14/46) of dedifferentiated, 5% (1/19) of myxoid or round cell, and 80% (8/10) of pleomorphic liposarcomas. Eighteen (16%) and one (1%) tumors were negative for ATRX and DAXX immunostaining, respectively. Remarkably, all cases with loss of either ATRX or DAXX expression had alternative lengthening of telomeres, and 83% (19/23) of tumors that had alternative lengthening of telomeres showed loss of either protein. The correlation between loss of either ATRX or DAXX and alternative telomere lengthening was 100% in dedifferentiated liposarcoma. The presence of alternative telomere lengthening in dedifferentiated liposarcoma suggested poor overall survival (hazard ratio=1.954, P=0.077) and was the most significant indicator of short progression-free survival (hazard ratio=3.119, P=0.003). In conclusion, we found that ATRX loss was

  9. Recurrence of Diabetic Pedal Ulcerations Following Tendo-Achilles Lengthening

    Directory of Open Access Journals (Sweden)

    Richard D. Weiner

    2011-05-01

    Full Text Available Foot and ankle surgeons are frequently challenged by the devastating systemic consequences of diabetes mellitus manifested through neuropathy, integumentary and joint breakdown, delayed healing, decreased ability to fight infection, and fragile tendon/ligaments. Diabetic neuropathic pedal ulcerations lead to amputations at an alarming rate and also carry a high mortality rate. This article will discuss causes of diabetic pedal ulcerations that persist or recur after tendo-Achilles lengthening and will highlight areas that need to be addressed by the practitioner such as infection, vascular and nutritional status, glucose control, off-loading, biomechanics, and patient compliance.

  10. Lengthening Temporalis Myoplasty: Virtual Animation-Assisted Technical Video.

    Science.gov (United States)

    Aljudaibi, Nawaf; Bennis, Yasmine; Duquennoy-Martinot, Veronique; Labbé, Daniel; Guerreschi, Pierre

    2016-09-01

    Lengthening temporalis myoplasty is a well-established procedure for dynamic palliative reanimation of the lip in facial palsy sequelae. The particularity of this technique is that the entire temporal muscle is transferred from the coronoid process to the upper half of the lip without interposition of aponeurotic tissue. To date, no video describing the technique was available. This is the first video describing the entire procedure, from preoperative markings through postoperative rehabilitation. In the video presented herein, the authors craft virtual three-dimensional animations in addition to a live operation on a patient performed by Daniel Labbé, who first described this technique 20 years ago. PMID:27556626

  11. Lengthening Temporalis Myoplasty: Virtual Animation-Assisted Technical Video.

    Science.gov (United States)

    Aljudaibi, Nawaf; Bennis, Yasmine; Duquennoy-Martinot, Veronique; Labbé, Daniel; Guerreschi, Pierre

    2016-09-01

    Lengthening temporalis myoplasty is a well-established procedure for dynamic palliative reanimation of the lip in facial palsy sequelae. The particularity of this technique is that the entire temporal muscle is transferred from the coronoid process to the upper half of the lip without interposition of aponeurotic tissue. To date, no video describing the technique was available. This is the first video describing the entire procedure, from preoperative markings through postoperative rehabilitation. In the video presented herein, the authors craft virtual three-dimensional animations in addition to a live operation on a patient performed by Daniel Labbé, who first described this technique 20 years ago.

  12. Technique, indications, and results of proximal medial gastrocnemius lengthening.

    Science.gov (United States)

    Barouk, Pierre

    2014-12-01

    Gastrocnemius proximal lengthening was first performed to correct spasticity in children, and was adapted for the patient with no neuromuscular condition in the late 1990s. Since then, the proximal gastrocnemius release has become less invasive and has evolved to include only the fascia overlying the medial head of the gastrocnemius muscle. The indications for performing this procedure are a clinically demonstrable gastrocnemius contracture that influences a variety of clinical conditions in the forefoot, hindfoot, and ankle. It is a safe and easy procedure that can be performed bilaterally simultaneously, and does not require immobilization of the ankle after surgery. PMID:25456723

  13. Limb lengthening over a nail can safely reduce the duration of external fixation

    OpenAIRE

    Chaudhary Milind

    2008-01-01

    Background: Limb lengthening using Ilizarov external fixation is safe, but the consolidation phase tends to take too long. A method that can safely reduce the time spent in external fixation would help increase patient tolerance and comfort. We report our results of lengthening over nails (LON) method in which an interlocking nail was used along with an Ilizarov external fixator to reduce external fixation duration in limb lengthening. This is a retrospective study. Materials and Methods: ...

  14. The effect on the extracellular matrix of the deep fascia in response to leg lengthening

    OpenAIRE

    Wei Yi-Yong; Wu Zi-Xiang; Li Xin-Kui; Wang Hai-Qiang; Luo Zhuo-Jing

    2008-01-01

    Abstract Background Whereas the alterations of diverse tissues in cellular and molecular levels have been investigated during leg lengthening via microscopy and biochemical studies, little is known about the response of deep fascia. This study aims to investigate the changes of the extracellular matrix in deep fascia in response to leg lengthening. Methods Animal model of leg lengthening was established in New Zealand white rabbits. Distraction was initiated at a rate of 1 mm/day and 2 mm/day...

  15. Comprehensive screening of alternative lengthening of telomeres phenotype and loss of ATRX expression in sarcomas.

    Science.gov (United States)

    Liau, Jau-Yu; Lee, Jen-Chieh; Tsai, Jia-Huei; Yang, Ching-Yao; Liu, Tsung-Lin; Ke, Zhi-Long; Hsu, Hung-Han; Jeng, Yung-Ming

    2015-12-01

    According to cytogenetic aberrations, sarcomas can be categorized as complex or simple karyotype tumors. Alternative lengthening of telomeres is a telomere-maintenance mechanism common in sarcomas. Recently, this mechanism was found to be associated with loss of either α-thalassemia/mental retardation syndrome X-linked (ATRX) or death domain-associated (DAXX) protein. We previously reported that alternative lengthening of telomeres and loss of ATRX expression were common in leiomyosarcoma, angiosarcoma, pleomorphic liposarcoma, and dedifferentiated liposarcoma. In the present study, we screened an additional 245 sarcomas of other types to determine the prevalence of alternative lengthening of telomeres, loss of ATRX/DAXX expression, and their relationship. Undifferentiated pleomorphic sarcomas were frequently alternative lengthening of telomeres positive (65%) and loss of ATRX was seen in approximately half of the alternative lengthening of telomeres-positive tumors. Nineteen of 25 myxofibrosarcomas were alternative lengthening of telomeres-positive, but only one was ATRX deficient. Three of 15 radiation-associated sarcomas were alternative lengthening of telomeres positive, but none of them was ATRX deficient. Alternative lengthening of telomeres and/or loss of ATRX were uncommon in malignant peripheral nerve sheath tumors, gastrointestinal stromal tumors, and embryonal rhabdomyosarcomas. By contrast, none of the 71 gene fusion-associated sarcomas was ATRX deficient or alternative lengthening of telomeres positive. All tumors exhibited preserved DAXX expression. Combining our previous studies and this study, a total of 384 sarcomas with complex karyotypes were examined, 83 of which were ATRX deficient (22%). By telomere-specific fluorescence in situ hybridization, 45% (138/308) were alternative lengthening of telomeres positive, 55% (76/138) of which were ATRX deficient. Loss of ATRX was highly associated with alternative lengthening of telomeres (Plengthening of

  16. [Combined crown lengthening surgery with restorative therapy for inducing papilla growth: a case report].

    Science.gov (United States)

    Le, Di; Hu, Wen-jie; Zhang, Hao

    2013-04-18

    A young lady with unsatisfied restorations of upper anterior teeth and swollen gum wanted to improve aesthetics. Oral examination showed that 12-22 were provisional crowns with normal occlusion, poorly gingival contour and gummy smile. The gingiva was red, light swollen and bleeding on probing. X-ray showed the roots of 11, 21 were short and the alveolar bone absorbed. After the periodontal initial treatment, an ideal location of gingival margin was determined. Then, an esthetic periodontal surgery was performed to recover the biology width and the gingival margin was fitted with the anterior teeth. The temporary restorations were made twice to guide the gingiva growth by changing the shape of the restorations and moving up the contact points of the restorations. The ceramic crowns were completed 3 months after the operation. The gummy smile disappeared and the gingival margin was filled well with the upper anterior ceramic crowns. The 14-month follow-up presented a satisfied effect. Crown lengthening surgery combined restorative therapy could lead papilla to grow well. This process is beneficial for the future treatment plan and clinical esthetic evaluation.

  17. Effects of lengthening contraction on calcium kinetics and skeletal muscle contractility in humans

    DEFF Research Database (Denmark)

    Nielsen, J S; Madsen, K; Jørgensen, L V;

    2005-01-01

    We have tested the hypothesis that the altered muscle contractility after lengthening contractions (LC) is caused by altered calcium (Ca2+) kinetics.......We have tested the hypothesis that the altered muscle contractility after lengthening contractions (LC) is caused by altered calcium (Ca2+) kinetics....

  18. Tibial lengthening for unilateral Crowe type-IV developmental dysplasia of the hip

    Directory of Open Access Journals (Sweden)

    Jun Wan

    2014-01-01

    Conclusions: Tibial lengthening may effectively correct gait and satisfactorily improve body image in young patients with unilateral Crowe type-IV DDH. Mono-lateral external fixator allows for accelerated postoperative rehabilitation and optimal preservation of ankle movements. Lengthening along with intramedullary nails may significantly reduce the external fixation time and the risk of fixator-related complications.

  19. Studies of RF Noise Induced Bunch Lengthening at the LHC

    CERN Document Server

    Mastoridis, T; Rivetta, C H; Baudrenghien, P; Butterworth, A C; Molendijk, J C

    2011-01-01

    Radio Frequency noise induced bunch lengthening can strongly affect the Large Hadron Collider performance through luminosity reduction, particle loss, and other effects. Models and theoretical formalisms demonstrating the dependence of the LHC longitudinal bunch length on the RF station noise spectral content have been presented*,**. Initial measurements validated these studies and determined the performance limiting RF components. For the existing LHC LLRF implementation the bunch length increases with a rate of 1 mm/hr, which is higher than the intrabeam scattering diffusion and leads to a 27% bunch length increase over a 20 hour store. This work presents measurements from the LHC that better quantify the relationship between the RF noise and longitudinal emittance blowup. Noise was injected at specific frequency bands and with varying amplitudes at the LHC accelerating cavities. The experiments presented in this paper confirmed the predicted effects on the LHC bunch length due to both the noise around the ...

  20. Radial Forcing and Edgar Allan Poe's Lengthening Pendulum

    CERN Document Server

    McMillan, Matthew; Whitney, Heather M

    2013-01-01

    Inspired by Edgar Allan Poe's The Pit and the Pendulum, we investigate a radially driven, lengthening pendulum. We first show that increasing the length of an undriven pendulum at a uniform rate does not amplify the oscillations in a manner consistent with the behavior of the scythe in Poe's story. We discuss parametric amplification and the transfer of energy (through the parameter of the pendulum's length) to the oscillating part of the system. In this manner radial driving may easily and intuitively be understood, and the fundamental concept applied in many other areas. We propose and show by a numerical model that appropriately timed radial forcing can increase the oscillation amplitude in a manner consistent with Poe's story. Our analysis contributes a computational exploration of the complex harmonic motion that can result from radially driving a pendulum, and sheds light on a mechanism by which oscillations can be amplified parametrically. These insights should prove especially valuable in the undergra...

  1. Alternative lengthening of telomeres: remodeling the telomere architecture

    Directory of Open Access Journals (Sweden)

    Dimitri eConomos

    2013-02-01

    Full Text Available To escape from the normal limits on proliferative potential, cancer cells must employ a means to counteract the gradual telomere attrition that accompanies semi-conservative DNA replication. While the majority of human cancers do this by up-regulating telomerase enzyme activity, most of the remainder use a homologous recombination-mediated mechanism of telomere elongation known as alternative lengthening of telomeres (ALT. Many molecular details of the ALT pathway are unknown, and even less is known regarding the mechanisms by which this pathway is activated. Here, we review current findings about telomere structure in ALT cells, including DNA sequence, shelterin content, and heterochromatic state. We speculate that remodeling of the telomere architecture may contribute to the emergence and maintenance of the ALT phenotype.

  2. An aggressive chondroblastoma of the knee treated with resection arthrodesis and limb lengthening using the Ilizarov technique

    Science.gov (United States)

    2010-01-01

    This case report describes the management of a 15 year old male with a biologically aggressive chondroblastoma of the knee. Following CT, bone scan, angiography and an open biopsy, the diagnosis was confirmed histologically and immunohistochemically. The patient underwent a 13 cm en-bloc excision of the knee, and knee arthrodesis with simultaneous bone transport using an Ilizarov ring fixator. Following 136 days of bone transport, the patient achieved radiological and clinical bony union after a total frame time of 372 days. He then commenced 50% partial weight-bear in a protective knee brace and gradually worked up to full weight-bearing by 4 months. The patient developed superficial pin tract infections around the k-wires on 2 occasions; these settled with a cephalosporin antibiotic spray and local dressings. At 13 years follow-up there are no signs of disease recurrence or failure at the fusion site. The patient is able to fully weight bear and stand independently on the operated leg. Knee arthrodesis with simultaneous limb-lengthening is an effective treatment modality following en-bloc resection of an aggressive chondroblastoma. The case is discussed with reference to the literature. PMID:20667131

  3. An aggressive chondroblastoma of the knee treated with resection arthrodesis and limb lengthening using the Ilizarov technique

    Directory of Open Access Journals (Sweden)

    Rakočević Zoran

    2010-07-01

    Full Text Available Abstract This case report describes the management of a 15 year old male with a biologically aggressive chondroblastoma of the knee. Following CT, bone scan, angiography and an open biopsy, the diagnosis was confirmed histologically and immunohistochemically. The patient underwent a 13 cm en-bloc excision of the knee, and knee arthrodesis with simultaneous bone transport using an Ilizarov ring fixator. Following 136 days of bone transport, the patient achieved radiological and clinical bony union after a total frame time of 372 days. He then commenced 50% partial weight-bear in a protective knee brace and gradually worked up to full weight-bearing by 4 months. The patient developed superficial pin tract infections around the k-wires on 2 occasions; these settled with a cephalosporin antibiotic spray and local dressings. At 13 years follow-up there are no signs of disease recurrence or failure at the fusion site. The patient is able to fully weight bear and stand independently on the operated leg. Knee arthrodesis with simultaneous limb-lengthening is an effective treatment modality following en-bloc resection of an aggressive chondroblastoma. The case is discussed with reference to the literature.

  4. Effective Lateral Canthal Lengthening with Triangular Rotation Flap

    Science.gov (United States)

    2016-01-01

    In Korea, lateral canthoplasty, along with medial epicanthoplasty, has become popular over the past years to widen the horizontal length of the palpebral fissure. However, the effect of the surgery differs greatly depending on the shape and structure of the eyes. If over-widened, complications such as eversion, scarring, and conjunctival exposure may occur. Thus, the author of this study suggests a more effective and safe method for lateral canthal lengthening that causes minimal complications. A total of 236 patients underwent lateral canthoplasty between July 2007 and December 2015. For each patient, a triangular flap 4–5 mm away from the lateral canthus was elevated and rotated 45 degrees laterally while the continuity of the lower eyelid gray line was maintained. A new lateral canthus was created by fixating the rotation flap to the lateral orbital rim with minimal skin trimming and tension-free sutures, preventing relapse and maintaining a triangular shape. In more than 95% of cases, effective and satisfactory extension was achieved. On average, a 3 mm extension of the lateral canthus was achieved. There were minor complications such as wound dehiscence, webbing, and scarring, which were easily corrected. The author not only extended the lateral canthus 3–4 mm laterally but also maintained the continuity of the gray line on the lower lid as a more natural-looking triangular shape, while minimizing complications such as webbing and conjunctival exposure.

  5. Radial forcing and Edgar Allan Poe's lengthening pendulum

    Science.gov (United States)

    McMillan, Matthew; Blasing, David; Whitney, Heather M.

    2013-09-01

    Inspired by Edgar Allan Poe's The Pit and the Pendulum, we investigate a radially driven, lengthening pendulum. We first show that increasing the length of an undriven pendulum at a uniform rate does not amplify the oscillations in a manner consistent with the behavior of the scythe in Poe's story. We discuss parametric amplification and the transfer of energy (through the parameter of the pendulum's length) to the oscillating part of the system. In this manner, radial driving can easily and intuitively be understood, and the fundamental concept applied in many other areas. We propose and show by a numerical model that appropriately timed radial forcing can increase the oscillation amplitude in a manner consistent with Poe's story. Our analysis contributes a computational exploration of the complex harmonic motion that can result from radially driving a pendulum and sheds light on a mechanism by which oscillations can be amplified parametrically. These insights should prove especially valuable in the undergraduate physics classroom, where investigations into pendulums and oscillations are commonplace.

  6. Bunch lengthening in the Fermilab main ring during storage

    International Nuclear Information System (INIS)

    There are two known current dependent effects which can increase the length of stored bunched beams: (1) a reduction of the potential well of the applied rf focusing system; and (2) induced unstable oscillations of the bunches, which can stabilize at a longer length by the process of Landau damping. In the first case, the current distribution in the bunches, interacting with induced electromagnetic fields in the walls, leaves a wake field which acts back on the bunches. A new equilibrium bunch shape results, different from that due to the applied rf, and this new equilibrium bunch shape will slowly establish itself as the particles within the bunch move on their new trajectories. The second form of bunch instability is the single bunch type. These are characterized by high frequency (i.e. within bunch) oscillations in the microwave region and fast growth rates. The coherent effects are very difficult to observe and such instabilities tend to simulate an incoherent growth in the bunch. An attempt is made to describe the observation of bunch lengthening in the main ring in terms of both potential well distortion and induced microwave fields. It is found that the increase in bunch size is in qualitative agreement with an induced microwave instability if the wall (i.e. chamber discontinuities) couples to beam with a broad resistive impedance in the microwave region of the order of Z/n approximately 75 OMEGA

  7. Bone tumor

    Science.gov (United States)

    Tumor - bone; Bone cancer; Primary bone tumor; Secondary bone tumor ... The cause of bone tumors is unknown. They often occur in areas of the bone that grow rapidly. Possible causes include: Genetic defects ...

  8. A cross-sectional survey of clinicians performing periodontal surgical crown lengthening.

    Science.gov (United States)

    Wyatt, Gillian; Grey, Nick; Deery, Chris

    2004-09-01

    The aim of this study was to conduct a survey of surgical crown lengthening practice performed by dental specialists and general dental practitioners using a cross-sectional questionnaire. One hundred general dental practitioners and 100 specialists from each of the following specialties: prosthodontics, periodontics, restorative dentistry and surgical dentistry. There were fewer surgical dentists performing surgical crown lengthening than the other specialists. The specialists in periodontics were significantly more likely to perform surgical crown lengthening than not. The respondents predominantly considered that periodontal surgical crown lengthening is within the remit of periodontics. 33% of the respondents performing more than 50 PSCL procedures in one year thought that the gingival margin was stable after three months. 33% thought that it was stable after six months and 33% declined to state a post-operative marginal stability time period.

  9. Comparing Laser and Scalpel for Soft Tissue Crown Lengthening: A Clinical Study.

    Science.gov (United States)

    Farista, Sana; Kalakonda, Butchibabu; Koppolu, Pradeep; Baroudi, Kusai; Elkhatat, Esam; Dhaifullah, Essam

    2016-02-24

    Crown lengthening procedure is aimed at exposure of sufficient crown structure accomplished by a gingivectomy, an apically positioned flap with osseous resection or the use of lasers. Our present clinical study is aimed to assess the clinical effectiveness of a diode laser for functional crown lengthening procedure and to compare it with the conventional procedure using the scalpel. Fourteen patients including males and females, aged 20- 40 years were recruited and divided into two groups to undergo crown lengthening either with the scalpel or the laser. The data obtained was analyzed for intergroup comparison with an Unpaired t-test and intragroup comparison was determined by ANOVA.Analysis of the intergroup results for pain showcased that there was a significant difference (Pcrown lengthening performed with the scalpel.

  10. Crown lengthening to facilitate restorative treatment in the presence of incomplete passive eruption.

    Science.gov (United States)

    Hempton, T J; Esrason, F

    2000-04-01

    Crown-lengthening surgery can be utilized to expose subgingival caries. In this clinical case, a patient presented with incomplete passive eruption in the maxillary anterior sextant. This case illustrates that when incomplete passive eruption is present and restorative treatment is necessary in the maxillary anterior sextant, crown-lengthening surgery not only provides exposure of subgingival caries but can also result in a more esthetic therapeutic outcome.

  11. Full mouth rehabilitation of partially and fully edentulous patient with crown lengthening procedure: a case report

    OpenAIRE

    Seol, Hyon-Woo; Koak, Jai-Young; Kim, Seong-Kyun; Heo, Seong-Joo

    2010-01-01

    BACKGROUND In order to restore severely attrited teeth properly, surgical intervention in the form of a crown-lengthening procedure may be required. And also, proper diagnosis and treatment sequencing is critical to obtain a successful results. Adequate diagnostic wax-up ensures good esthetics and healthy periodontal tissue. CASE DESCRIPTION This clinical case report describes a diagnostically based protocol for restoration on mandibular anterior teeth with crown lengthening procedure and the...

  12. Telomere elongation involves intra-molecular DNA replication in cells utilizing alternative lengthening of telomeres

    OpenAIRE

    Muntoni, Alessandra; Neumann, Axel A.; Hills, Mark; Reddel, Roger R

    2008-01-01

    Alternative lengthening of telomeres (ALT) is a telomere length maintenance mechanism based on recombination, where telomeres use other telomeric DNA as a template for DNA synthesis. About 10% of all human tumors depend on ALT for their continued growth, and understanding its molecular details is critically important for the development of cancer treatments that target this mechanism. We have previously shown that telomeres of ALT-positive human cells can become lengthened via inter-telomeric...

  13. Z-plasty lengthening for iliotibial band friction syndrome.

    Science.gov (United States)

    Barber, F Alan; Boothby, Michael H; Troop, Randal L

    2007-10-01

    Iliotibial band friction syndrome presents with lateral knee pain usually in runners. When conservative treatment fails, surgical lengthening, or Z-plasty, can provide symptomatic relief. This retrospective study evaluated the long-term results of iliotibial band Z-plasty for chronic iliotibial band friction syndrome in a consecutive series of patients. Inclusion criteria were failed nonoperative treatment for symptomatic iliotibial band friction syndrome for at least 3 months, minimum age of 17 years, and closed growth plates. Exclusion criteria were history of significant trauma, prior knee surgery, lateral compartment pathology, and anterior or posterior cruciate ligament instability. Postoperative evaluation included annual physical examination consisting of Tegner, Lysholm, Cincinnati, and International Knee Documentation Committee (IKDC) activity scores. Of an initial group of 11 patients, 8 were evaluated an average of 75.6 months postoperatively (range: 59-97 months). Average length of preoperative symptoms was 15.6 months (range: 3-36 months), and average length of nonoperative management was 6.9 months (range: 3-24 months). Postoperatively, mean Cincinnati score was 82.9 (range: 55-95), Tegner score was 4.4 (range: 2-7), Lysholm score was 88.6 (range: 57-100), and IKDC activity score was 2.6 (range: 1-4). No adverse events occurred during surgery. All patients reported complete resolution of lateral knee pain and a full return to preoperative activity levels. Iliotibial Z-plasty was successful for refractory iliotibial band friction syndrome. This improvement was maintained out to 8 years after surgery.

  14. Transplantation of Autologous Bone Marrow Mesenchymal Stem Cells with Platelet-Rich Plasma Accelerate Distraction Osteogenesis in A Canine Model

    OpenAIRE

    2015-01-01

    Objective: Distraction osteogenesis (DO) is a surgical procedure used to generate large volumes of new bone for limb lengthening. Materials and Methods: In this animal experimental study, a 30% lengthening of the left tibia (mean distraction distance: 60.8 mm) was performed in ten adult male dogs by callus distraction after osteotomy and application of an Ilizarov fixator. Distraction was started on postoperative day seven with a distraction rate of 0.5 mm twice per day and car...

  15. Bone Biopsy

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Bone Biopsy Bone biopsy uses a needle and imaging guidance ... limitations of Bone Biopsy? What is a Bone Biopsy? A bone biopsy is an image-guided procedure ...

  16. Bone Diseases

    Science.gov (United States)

    ... avoid smoking and drinking too much alcohol. Bone diseases can make bones easy to break. Different kinds ... break Osteogenesis imperfecta makes your bones brittle Paget's disease of bone makes them weak Bones can also ...

  17. Cambios dimensionales de los tejidos en los procedimientos de alargamiento coronario Dimensional changes in tissues after crown lengthening procedures

    Directory of Open Access Journals (Sweden)

    C. Álvarez-Novoa García

    2012-08-01

    : We performed a search in PubMed with the keyword "crown lengthening", limited to English language articles, that were published between the years 1990-2009, which were clinical trials. The recovery of documents was held in the periodicals of the Faculty of Dentistry in UCM, and in Compludoc database. Two evaluators reviewed the papers individually. Results and Discussion: The seven articles, including studies in both animals and humans, which were included in the review, analyzing gingival index, bone level, probing depth, attachment level and biological width, and crown length and the position of the gingival margin. Conclusions: Bone level is altered during the first 3 months, but thereafter remains constant. The longer-term studies found no significant differences in bone probing depth at 6 and 12 months after the surgery.

  18. The contractile response during steady lengthening of stimulated frog muscle fibres.

    Science.gov (United States)

    Lombardi, V; Piazzesi, G

    1990-12-01

    1. Steady lengthenings at different velocities (0.025-1.2 microns/s per half-sarcomere; temperature 2-5.5 degrees C) were imposed on isolated frog muscle fibres at the isometric tetanus plateau by means of a loudspeaker motor. The lengthening at the sarcomere level was measured by means of a striation follower either in fixed-end or in length-clamp mode. The force response was measured by a capacitance gauge transducer (resonance frequency 50 kHz). Preparations showing gross non-homogeneity during lengthening were excluded. 2. A steady tension was in all cases reached after about 20 nm per half-sarcomere of lengthening. Tension during this steady phase rose with speed of elongation up to 0.25-0.4 micron/s per half-sarcomere, when tension was 1.9-2 times isometric tetanic force (T0). Further increase in speed produced only very little increase in the steady tension. 3. During the transitory phase, before steady tension was reached, the tension rose monotonically if speed of lengthening was less than 0.25-0.3 micron/s per half-sarcomere; at higher speed the tension rose above the steady level, reaching a peak when extension was 10-14 nm per half-sarcomere, and then fell to the steady level. Tension at the peak continued to rise with speed of lengthening above 0.3 micron/s per half-sarcomere. 4. During the tension rise within the transitory phase of force response the segment elongated at a speed 15-20% lower than that imposed on the whole fibre, as a consequence of tendon compliance. 5. During the steady phase, non-homogeneity of lengthening speed began above a speed of lengthening which varied from fibre to fibre. At speeds below this value, segments elongated at the same speed as that imposed on the fibre. 6. Tension responses to large step stretches (up to 12 nm per half-sarcomere), applied at the plateau of isometric tetanus, showed that the instantaneous elasticity of contractile machinery is not responsible for the limit in force attained with high

  19. Crown lengthening in the maxillary anterior region: a 6-month prospective clinical study.

    Science.gov (United States)

    Deas, David E; Mackey, Scott A; Sagun, Ruben S; Hancock, Raymond H; Gruwell, Scott F; Campbell, Casey M

    2014-01-01

    The purpose of this study was to assess osseous parameters and stability of maxillary anterior teeth following crown lengthening surgery. Thirty-six patients requiring facial crown lengthening of 277 maxillary anterior and first premolar teeth were included. Presurgical and intraoperative clinical measurements were recorded at baseline and 1, 3, and 6 months postsurgery at midfacial, mesiofacial, and distofacial line angles. The data presented here suggest that when crown lengthening anterior maxillary teeth, the distance between the desired gingival margin and alveolar crest is usually insufficient to allow for biologic width. In addition, there is significant tissue rebound that may stabilize by 6 months. Tissue rebound appears related to flap position relative to the alveolar crest at suturing. These findings suggest that clinicians should establish proper anterior crown length with osseous resection.

  20. The effect on the extracellular matrix of the deep fascia in response to leg lengthening

    Directory of Open Access Journals (Sweden)

    Wei Yi-Yong

    2008-07-01

    Full Text Available Abstract Background Whereas the alterations of diverse tissues in cellular and molecular levels have been investigated during leg lengthening via microscopy and biochemical studies, little is known about the response of deep fascia. This study aims to investigate the changes of the extracellular matrix in deep fascia in response to leg lengthening. Methods Animal model of leg lengthening was established in New Zealand white rabbits. Distraction was initiated at a rate of 1 mm/day and 2 mm/day in two steps, and preceded until increases of 10% and 20% in the initial length of tibia had been achieved. Alcian blue stain and picrosirius-polarization method were used for the study of the extracellular matrix of deep fascia samples. Leica DM LA image analysis system was used to investigate the quantitative changes of collagen type I and III. Results Alcian blue stain showed that glycosaminoglycans of fascia of each group were composed of chondroitin sulphate and heparin sulphate, but not of keratan sulphate. Under the polarization microscopy, the fascia consisted mainly of collagen type I. After leg lengthening, the percentage of collagen type III increased. The most similar collagen composition of the fascia to that of the normal fascia was detected at a 20% increase in tibia length achieved via a distraction rate of 1 mm/d. Conclusion The changes in collagen distribution and composition occur in deep fascia during leg lengthening. Although different lengthening schemes resulted in varied matrix changes, the most comparable collagen composition to be demonstrated under the scheme of a distraction rate of 1 mm/day and 20% increase in tibia length. Efficient fascia regeneration is initiated only in certain combinations of the leg load parameters including appropriate intensity and duration time, e.g., either low density distraction that persist a relatively short time or high distraction rates.

  1. Crown lengthening with removable orthodontics: a combined approach for ideal esthetics.

    Science.gov (United States)

    Reyes, Elio; Barrow, Sarah; McLeod, Dwight E

    2011-01-01

    Cases in which a single tooth is in need of crown lengthening while remaining esthetically pleasing represent a unique challenge. A case is presented here in which crown lengthening in a challenging esthetic situation on a canine was achieved through forced eruption with a removable orthodontic appliance. The case was considered a success by both the clinician and the patient. Fabrication of the acrylic stent is a simple procedure that can be completed chairside, and the patient's acceptance of the appliance as well as the overall cost and time invested made this a very convenient alternative. The report emphasizes the general dentist's complete control over each treatment sequence.

  2. Multidisciplinary and esthetic approach to clinical crown lengthening: report of a case.

    Science.gov (United States)

    Ngan, P; Knobloch, L

    1993-12-01

    This paper describes the combined efforts of an orthodontist, periodontist, and a restorative dentist to save an unrestorable tooth by clinical crown lengthening. A maxillary lateral incisor, originally treatment planned for extraction, was treated with orthodontic extrusion, circumferential fiberotomy, and metal-ceramic crown restoration. To maximize the esthetic appearance of the tooth during orthodontic treatment, an acrylic resin facing was designed together with the orthodontic appliance used to facilitate vertical extrusion. Clinical crown lengthening may be used as an alternative approach to the treatment of severely broken down anterior teeth.

  3. Mathematical Basis of Idea That Harmonious Marriage Can Lengthen Life-span

    Institute of Scientific and Technical Information of China (English)

    Zhi-qiang Zhang

    2009-01-01

    It is a very important issue for us to explore the effects of the marriage to life. In recent years, many scholars have proved that the marriage can lengthen life-span from different angles. With the development of theory of dependence random variables, we discuss the effects of the marriage to life and provide a mathematical basis of the idea that the harmonious marriage can lengthen life-span in this paper. Meanwhile, we analyze the impact of the marriage on life on the basis of the net single premium.

  4. Molecular mechanisms of activity and derepression of alternative lengthening of telomeres.

    Science.gov (United States)

    Pickett, Hilda A; Reddel, Roger R

    2015-11-01

    Alternative lengthening of telomeres (ALT) involves homology-directed telomere synthesis. This multistep process is facilitated by loss of the ATRX or DAXX chromatin-remodeling factors and by abnormalities of the telomere nucleoprotein architecture, including altered DNA sequence and decreased TRF2 saturation. Induction of telomere-specific DNA damage triggers homology-directed searches, and NuRD-ZNF827 protein-protein interactions provide a platform for the telomeric recruitment of homologous recombination (HR) proteins. Telomere lengthening proceeds by strand exchange and template-driven DNA synthesis, which culminates in dissolution of HR intermediates. PMID:26581522

  5. Coexistence of Alternative Lengthening of Telomeres and Telomerase in hTERT-Transfected GM847 Cells

    OpenAIRE

    Perrem, Kilian; Colgin, Lorel M.; Neumann, Axel A.; Yeager, Thomas R.; Reddel, Roger R

    2001-01-01

    It has been shown previously that some immortalized human cells maintain their telomeres in the absence of significant levels of telomerase activity by a mechanism referred to as alternative lengthening of telomeres (ALT). Cells utilizing ALT have telomeres of very heterogeneous length, ranging from very short to very long. Here we report the effect of telomerase expression in the ALT cell line GM847. Expression of exogenous hTERT in GM847 (GM847/hTERT) cells resulted in lengthening of the sh...

  6. Cosmetic Lateral Canthoplasty: Lateral Canthoplasty to Lengthen the Lateral Canthal Angle and Correct the Outer Tail of the Eye.

    Science.gov (United States)

    Chae, Soo Wook; Yun, Byung Min

    2016-07-01

    There are many women who want larger and brighter eyes that will give a favorable impression. Surgical methods that make the eye larger and brighter include double eyelidplasty, epicanthoplasty, as well as lateral canthoplasty. Double eyelidplasty produces changes in the vertical dimension of the eyes, whereas epicanthoplasty and lateral canthoplasty create changes in the horizontal dimension of the eyes. Epicanthoplasty, a surgical procedure which enlarges the eye horizontally, is performed at the inner corner of the eye, whereas lateral canthoplasty enlarges the outer edge of the eye. In particular, if the slant of the palpebral fissure is raised and the horizontal dimension of the palpebral fissure is short, adjusting the slant of the palpebral fissure through lateral canthoplasty can achieve an enlargement of eye width and smoother features. Depending on the patient's condition, even better results can be achieved if this procedure is performed in conjunction with other procedures, such as double eyelidplasty, epicanthoplasty, eye roll formation surgery, fat graft, and facial bone contouring surgery. In this paper, the authors will introduce in detail their surgical method for a cosmetic lateral canthoplasty that lengthens the lateral canthal angle and corrects the outer tail of the eyes, in order to ease the unfavorable impression. PMID:27462564

  7. Cosmetic Lateral Canthoplasty: Lateral Canthoplasty to Lengthen the Lateral Canthal Angle and Correct the Outer Tail of the Eye

    Science.gov (United States)

    Yun, Byung Min

    2016-01-01

    There are many women who want larger and brighter eyes that will give a favorable impression. Surgical methods that make the eye larger and brighter include double eyelidplasty, epicanthoplasty, as well as lateral canthoplasty. Double eyelidplasty produces changes in the vertical dimension of the eyes, whereas epicanthoplasty and lateral canthoplasty create changes in the horizontal dimension of the eyes. Epicanthoplasty, a surgical procedure which enlarges the eye horizontally, is performed at the inner corner of the eye, whereas lateral canthoplasty enlarges the outer edge of the eye. In particular, if the slant of the palpebral fissure is raised and the horizontal dimension of the palpebral fissure is short, adjusting the slant of the palpebral fissure through lateral canthoplasty can achieve an enlargement of eye width and smoother features. Depending on the patient's condition, even better results can be achieved if this procedure is performed in conjunction with other procedures, such as double eyelidplasty, epicanthoplasty, eye roll formation surgery, fat graft, and facial bone contouring surgery. In this paper, the authors will introduce in detail their surgical method for a cosmetic lateral canthoplasty that lengthens the lateral canthal angle and corrects the outer tail of the eyes, in order to ease the unfavorable impression. PMID:27462564

  8. Bone Grafts

    Science.gov (United States)

    ... repair and rebuild diseased bones in your hips, knees, spine, and sometimes other bones and joints. Grafts can also repair bone loss caused by some types of fractures or cancers. Once your body accepts the bone ...

  9. Compensatory Vowel Lengthening for Omitted Coda Consonants: A Phonetic Investigation of Children's Early Representations of Prosodic Words

    Science.gov (United States)

    Song, Jae Yung; Demuth, Katherine

    2008-01-01

    Children's early word productions often differ from the target form, sometimes exhibiting vowel lengthening when word-final coda consonants are omitted (e.g., "dog" /d[open o]g/ [arrow right] [d[open o]:]). It has typically been assumed that such lengthening compensates for a missing prosodic unit (a mora). However, this study raises the…

  10. Bone within a bone

    Energy Technology Data Exchange (ETDEWEB)

    Williams, H.J.; Davies, A.M. E-mail: wendy.turner@roh.nhs.uk; Chapman, S

    2004-02-01

    The 'bone within a bone' appearance is a well-recognized radiological term with a variety of causes. It is important to recognize this appearance and also to be aware of the differential diagnosis. A number of common conditions infrequently cause this appearance. Other causes are rare and some remain primarily of historical interest, as they are no longer encountered in clinical practice. In this review we illustrate some of the conditions that can give the bone within a bone appearance and discuss the physiological and pathological aetiology of each where known.

  11. Treatment of tibial defect and bone nonunion with limb shortening with external fixator and reconstituted bone xenograft

    Institute of Scientific and Technical Information of China (English)

    王志刚; 刘建; 胡蕴玉; 孟国林; 金格勒; 袁志; 王海强; 戴先文

    2003-01-01

    Objective: To explore the effect of external fixator and reconstituted bone xenograft (RBX) in the treatment of tibial bone defect, tibial bone nonunion and congenital pseudarthrosis of the tibia with limb shortening. Methods: Twenty patients ( 13 males and 7 females) with tibial bone defect, tibial bone nonunion or congenital pseudarthrosis of the tibia with limb shortening were treated with external fixation. Two kinds of external fixators were used: a half ring sulcated external fixator used in 13 patients and a combined external fixator in 7 patients. Foot-drop was corrected at the same time with external fixation in 4 patients. The shortened length of the tibia was in the range of 2-9 cm, with an average of 4.8 cm. For bone grafting, RBX was used in 12 patients, autogenous ilium was used in 3 patients and autogenous fibula was implanted as a bone plug into the medullary canal in 1 case, and no bone graft was used in 4 patients. Results: All the 20 patients were followed-up for 8 months to 7 years, averaging 51 months. Satisfactory function of the affected extremities was obtained. All the shortened extremities were lengthened to the expected length. For all the lengthening area and the fracture sites, bone union was obtained at the last. The average healing time of 12 patients treated with RBX was 4.8 months. Conclusions: Both the half ring sulcated external fixator and the combined external fixator have the advantages of small trauma, simple operation, elastic fixation without stress shielding and non-limitation from local soft tissue conditions, and there is satisfactory functional recovery of affected extremities in the treatment of tibial bone defects, tibial bone nonunion and congenital pseudarthrosis of the tibia combined with limb shortening. RBX has good biocompatibility and does not cause immunological rejections. It can also be safely used in treatment of bone nonunion and has reliable effect to promote bone healing.

  12. Limb lengthening over a nail can safely reduce the duration of external fixation

    Directory of Open Access Journals (Sweden)

    Chaudhary Milind

    2008-01-01

    Full Text Available Background: Limb lengthening using Ilizarov external fixation is safe, but the consolidation phase tends to take too long. A method that can safely reduce the time spent in external fixation would help increase patient tolerance and comfort. We report our results of lengthening over nails (LON method in which an interlocking nail was used along with an Ilizarov external fixator to reduce external fixation duration in limb lengthening. This is a retrospective study. Materials and Methods: Twenty-seven lengthening surgeries were done with the LON method in 23 patients with 22 tibiae and five femora during the last 12 years. Length gain ranged from 1.5 cm to a maximum of 9.8 cm with a mean of 4.6 cm. The mean modified Paley difficulty score was 7.6 points. Fourteen associated procedures were performed in these patients, including equinus contracture releases, supracondylar osteotomies, ilizarov hip reonstruction and ankle fusion. We had a 29% rate of complications which included one problem, three obstacles and four complications with no serious deep intramedullary infections. Our rate of complications compares favorably with series reported in the literature. External fixation duration was reduced significantly to a mean of 17.8 days per cm. Conclusions: A combination of intramedullary nailing along with external fixation significantly reduces external fixation time while maintaining low rate of complications. Great care needs to be taken to prevent pin track infection and deep intramedullary sepsis.

  13. [An esthetic crown lengthening technic of the clinical crown. Rapid orthodontic extrusion].

    Science.gov (United States)

    Blase, D; Bercy, P

    1993-01-01

    Rapid orthodontic root extrusion is an esthetic technique for clinical crown lengthening. Associated with periodontal surgery, it exposes subgingival lesions and preserves an harmonious gingivo-osseous morphology. This conservative technique is easy to apply by the general dentist as it requires non specialised material.

  14. Leg Lengthening as a Means of Improving Ambulation Following an Internal Hemipelvectomy

    Directory of Open Access Journals (Sweden)

    Wakyo Sato

    2016-01-01

    Full Text Available Reconstructive surgery following an internal hemipelvectomy for a malignant pelvic tumor is difficult due to the structural complexity of the pelvis and the massive extension of the tumor. While high complication rates have been encountered in various types of reconstructive surgery, resection without reconstruction reportedly involved fewer complications. However, this method often results in limb shortening with resultant instability during walking. We reported herein leg lengthening performed to correct lower limb shortening after an internal hemipelvectomy, which improved ambulatory stability and overall QOL. An 18-year-old male patient came to our hospital to correct a lower limb discrepancy resulting from a left internal hemipelvectomy. His left pelvis and proximal femur had been resected, and the femur remained without an acetabular roof. His left lower limb was about 8 centimeters shorter. The left tibia was lengthened 8 centimeters with an external fixator. After the lengthening, the patient was able to walk without support and his gait remarkably improved. Additionally he no longer required placing a wallet in his back pocket as a pad as a means of raising the left side of his torso while sitting. Leg lengthening was a useful method of improving ambulation after an internal hemipelvectomy.

  15. Intraoral distraction osteogenesis to lengthen the ascending ramus - Experience with seven patients

    NARCIS (Netherlands)

    Jansma, J; Bierman, MWJ; Becking, AG

    2004-01-01

    Seven children with facial asymmetry, mean age 12 years (range 11-14.5) were treated by intraoral distraction osteogenesis to lengthen the hypoplastic ramus. We achieved a mean increase in length of the ramus of 13 mm (range 10-16). In only one patient did we achieve a posterior open bite on the dis

  16. Precise and feasible measurements of lateral calcaneal lengthening osteotomies by radiostereometric analysis in cadaver feet

    DEFF Research Database (Denmark)

    Martinkevich, P; Rahbek, Ole; Møller-Madsen, B;

    2015-01-01

    osteotomy (LCLO). METHODS: LCLO was performed in six fixed adult cadaver feet. Tantalum markers were inserted on each side of the osteotomy and in the cuboideum. Lengthening was done with a plexiglas wedge. A total of 24 radiological double examinations were obtained. Two feet were excluded due to loose...

  17. Foot lengthening and shortening during gait: a parameter to investigate foot function?

    NARCIS (Netherlands)

    Stolwijk, N.M.; Koenraadt, K.L.M.; Louwerens, J.W.; Grim, D.; Duysens, J.E.J.; Keijsers, N.L.W.

    2014-01-01

    INTRODUCTION: Based on the windlass mechanism theory of Hicks, the medial longitudinal arch (MLA) flattens during weight bearing. Simultaneously, foot lengthening is expected. However, changes in foot length during gait and the influence of walking speed has not been investigated yet. METHODS: The f

  18. A Comparative Evaluation for Biologic Width following Surgical Crown Lengthening Using Gingivectomy and Ostectomy Procedure

    Directory of Open Access Journals (Sweden)

    Kiran Kumar Ganji

    2012-01-01

    Full Text Available Surgical crown lengthening has been proposed as a means of facilitating restorative procedures and preventing injuries in teeth with structurally inadequate clinical crown or exposing tooth structure in the presence of deep, subgingival pathologies which may hamper the access for proper restorative measures. Histological studies utilizing animal models have shown that postoperative crestal resorption allowed reestablishment of the biologic width. However, very little has been done in humans. Aims. The purpose of the study was to evaluate the potential changes in the periodontal tissues, particularly the biologic width, following surgical crown lengthening by two surgical procedures before and after crown placement. Methods and Material. Twenty (20 patients who needed surgical crown lengthening to gain retention necessary for prosthetic treatment and/or to access caries, tooth fracture, or previous prosthetic margins entered the study. The following parameters were obtained from line angles of treated teeth (teeth requiring surgical crown lengthening and adjacent sites: Plaque and Gingival Indices (PI & (GI, Position of Gingival Margin from reference Stent (PGMRS, Probing depth (PD, and Biologic Width (BW. Statistical Analysis Used. Student “t” Test. Results. Initial baseline values of biologic width were 2.55 mm (Gingivectomy procedure B1 Group and 1.95 mm (Ostectomy procedure B2 Group and after surgical procedure the values were 1.15 mm and 1.25 mm. Conclusions. Within the limitations of the study the biologic width, at treated sites, was re-established to its original vertical dimension by 3 months. Ostectomy with apically positioned flap can be considered as a more effective procedure than Gingivectomy for Surgical Crown Lengthening.

  19. A Comparative Evaluation for Biologic Width following Surgical Crown Lengthening Using Gingivectomy and Ostectomy Procedure.

    Science.gov (United States)

    Ganji, Kiran Kumar; Patil, Veena Ashok; John, Jiji

    2012-01-01

    Surgical crown lengthening has been proposed as a means of facilitating restorative procedures and preventing injuries in teeth with structurally inadequate clinical crown or exposing tooth structure in the presence of deep, subgingival pathologies which may hamper the access for proper restorative measures. Histological studies utilizing animal models have shown that postoperative crestal resorption allowed reestablishment of the biologic width. However, very little has been done in humans. Aims. The purpose of the study was to evaluate the potential changes in the periodontal tissues, particularly the biologic width, following surgical crown lengthening by two surgical procedures before and after crown placement. Methods and Material. Twenty (20) patients who needed surgical crown lengthening to gain retention necessary for prosthetic treatment and/or to access caries, tooth fracture, or previous prosthetic margins entered the study. The following parameters were obtained from line angles of treated teeth (teeth requiring surgical crown lengthening) and adjacent sites: Plaque and Gingival Indices (PI) & (GI), Position of Gingival Margin from reference Stent (PGMRS), Probing depth (PD), and Biologic Width (BW). Statistical Analysis Used. Student "t" Test. Results. Initial baseline values of biologic width were 2.55 mm (Gingivectomy procedure B1 Group) and 1.95 mm (Ostectomy procedure B2 Group) and after surgical procedure the values were 1.15 mm and 1.25 mm. Conclusions. Within the limitations of the study the biologic width, at treated sites, was re-established to its original vertical dimension by 3 months. Ostectomy with apically positioned flap can be considered as a more effective procedure than Gingivectomy for Surgical Crown Lengthening.

  20. Oral Crest Lengthening for Increasing Removable Denture Retention by Means of CO2 Laser

    Directory of Open Access Journals (Sweden)

    Samir Nammour

    2014-01-01

    Full Text Available The loss of teeth and their replacement by artificial denture is associated with many problems. The denture needs a certain amount of ridge height to give it retention and a long-term function. Crest lengthening procedures are performed to provide a better anatomic environment and to create proper supporting structures for more stability and retention of the denture. The purpose of our study is to describe and evaluate the effectiveness of CO2 laser-assisted surgery in patients treated for crest lengthening (vestibular deepening. There have been various surgical techniques described in order to restore alveolar ridge height by pushing muscles attaching of the jaws. Most of these techniques cause postoperative complications such as edemas, hemorrhage, pain, infection, slow healing, and rebound to initial position. Our clinical study describes the treatment planning and clinical steps for the crest lengthening with the use of CO2 laser beam (6–15 Watts in noncontact, energy density range: 84.92–212.31 J/cm2, focus, and continuous mode with a focal point diameter of 0.3 mm. At the end of each surgery, dentures were temporarily relined with a soft material. Patients were asked to mandatorily wear their relined denture for a minimum of 4–6 weeks and to remove it for hygienic purposes. At the end of each surgery, the deepest length of the vestibule was measured by the operator. No sutures were made and bloodless wounds healed in second intention without grafts. Results pointed out the efficiency of the procedure using CO2 laser. At 8 weeks of post-op, the mean of crest lengthening was stable without rebound. Only a loss of 15% was noticed. To conclude, the use of CO2 laser is an effective option for crest lengthening.

  1. Callus features of regenerate fracture cases in femoral lengthening in achondroplasia

    International Nuclear Information System (INIS)

    We studied the callus features seen in cases of regenerate fracture in femoral lengthening using a monolateral fixator in achondroplasia to determine whether callus types and shapes can predict the probability of callus fracture. The radiographs of 28 cases of femoral lengthening in 14 patients, 14 cases of callus fracture, and 14 cases without callus fracture were retrospectively analyzed by four observers and classified into different shapes and types in concordance with the Ru Li classification. The average lengthening of 9.4 cm (range 7.5-11.8 cm) was achieved, which was 41% (range 30-55%) of the original length and the average timing of callus fracture was 470 days (range 440-545 days) after surgery in the callus fracture group. While the average lengthening of 9.1 cm (range 8-9.7 cm) was achieved, this was 30% (range 28-32%) of the original length in the group of patients without callus fracture. The callus was atypically shaped, there was a 48% average (range 30-72%) reduction of the callus width compared with the natural width of the femur, and a lucent pathway was present in all cases of regenerate fracture. A lucent pathway was seen in all fracture cases with concave, lateral, and atypical shapes, and there was more than 30% lengthening and 30% reduction of the callus width compared with the natural width of the femur, which are the warning signs for regenerate fractures. These signs help the surgeon to predict the outcome and guide him in planning for any additional interventions. The Ru Li classification is an effective method for the evaluation of the chance of callus fracture. (orig.)

  2. Callus features of regenerate fracture cases in femoral lengthening in achondroplasia

    Energy Technology Data Exchange (ETDEWEB)

    Devmurari, Kamlesh N.; Song, Hae Ryong; Modi, Hitesh N.; Venkatesh, K.P.; Ju, Kim Seung; Song, Sang Heon [Korea University Medical College, Institute for Rare Diseases and Department of Orthopedic Surgery, Seoul (Korea)

    2010-09-15

    We studied the callus features seen in cases of regenerate fracture in femoral lengthening using a monolateral fixator in achondroplasia to determine whether callus types and shapes can predict the probability of callus fracture. The radiographs of 28 cases of femoral lengthening in 14 patients, 14 cases of callus fracture, and 14 cases without callus fracture were retrospectively analyzed by four observers and classified into different shapes and types in concordance with the Ru Li classification. The average lengthening of 9.4 cm (range 7.5-11.8 cm) was achieved, which was 41% (range 30-55%) of the original length and the average timing of callus fracture was 470 days (range 440-545 days) after surgery in the callus fracture group. While the average lengthening of 9.1 cm (range 8-9.7 cm) was achieved, this was 30% (range 28-32%) of the original length in the group of patients without callus fracture. The callus was atypically shaped, there was a 48% average (range 30-72%) reduction of the callus width compared with the natural width of the femur, and a lucent pathway was present in all cases of regenerate fracture. A lucent pathway was seen in all fracture cases with concave, lateral, and atypical shapes, and there was more than 30% lengthening and 30% reduction of the callus width compared with the natural width of the femur, which are the warning signs for regenerate fractures. These signs help the surgeon to predict the outcome and guide him in planning for any additional interventions. The Ru Li classification is an effective method for the evaluation of the chance of callus fracture. (orig.)

  3. Tibial lengthening over humeral and tibial intramedullary nails in patients with sequelae of poliomyelitis: a comparative study.

    Science.gov (United States)

    Chen, Daoyun; Chen, Jianmin; Jiang, Yao; Liu, Fanggang

    2011-06-01

    Leg discrepancy is common after poliomyelitis. Tibial lengthening is an effective way to solve this problem. It is believed lengthening over a tibial intramedullary nail can provide a more comfortable lengthening process than by the conventional technique. However, patients with sequelae of poliomyelitis typically have narrow intramedullary canals allowing limited space for inserting a tibial intramedullary nail and Kirschner wires. To overcome this problem, we tried using humeral nails instead of tibial nails in the lengthening procedure. In this study, we used humeral nails in 20 tibial lengthening procedures and compared the results with another group of patients who were treated with tibial lengthening over tibial intramedullary nails. The mean consolidation index, percentage of increase and external fixation index did not show significant differences between the two groups. However, less blood loss and shorter operating time were noted in the humeral nail group. More patients encountered difficulty with the inserted intramedullary nail in the tibial nail group procedure. The complications did not show a statistically significant difference between the two techniques on follow-up. In conclusion, we found the humeral nail lengthening technique was more suitable in leg discrepancy patients with sequelae of poliomyelitis.

  4. Evaluation of the Prevalence of Different Treatment Failure Modes after Crown Lengthening Surgical Procedures

    Directory of Open Access Journals (Sweden)

    Amirreza Babaloo

    2016-07-01

    Full Text Available Introduction: Preservation of the health of periodontium is very important for the long-term success of restored teeth and a balance should always be created between the patients’ esthetic requirements and the periodontal health. Failures of crown lengthening procedures are classified into early and late failures. The aim of this study was to evaluate the prevalence of early failures of crown leathering surgical procedures. Materials and methods: In this descriptive/cross-sectional study, 96 patients were selected from those referring to the Department of Periodontitis, Tabriz Faculty of Dentistry, who required crown lengthening procedures. The particulars of these patients were recorded in special forms and the reasons for the failure of surgical procedures were separately determined at 2- and 6-week intervals. In addition, the frequencies of the reasons for failures were determined in percentages and absolute frequencies. Data were analyzed with descriptive statistics (frequencies and percentages using SPSS 21. Statistical significance was set at P<0.05. Results: Evaluation of patients 6 weeks after surgery showed a failure rate of 14.5% for crown lengthening procedures in patients referring to the Department of Periodontics, Tabriz Faculty of Dentistry. The most common reasons for such early failures in the 6th week, in descending order, were a lack of sufficient keratinized gingiva around in tooth in question, fracture of the tooth structure after surgery, inadequate surgery (not creating a proper distance between the healthy margin and the crest and the coronal returning of the gingival tissue on the tooth. A lack of sufficient keratinized gingiva around the tooth was the most frequent reason for the early failure of crown lengthening procedure at both study intervals. Conclusion: It can be concluded from the results of the present study that during the 6th postoperative week the crown lengthening procedures exhibited a 14.5% failure rate

  5. Esthetic Rehabilitation through Crown Lengthening Surgery and Conservative CAD/CAM Veneers: A Multidisciplinary Case Report.

    Science.gov (United States)

    Passos, Leandro; Soares, Fernando Peixoto; Gallo, Mauricio

    2016-01-01

    This case report describes a successful multidisciplinary approach used to improve the smile esthetics of a patient presenting with excessive gingival display, asymmetric gingival margins, and small upper anterior teeth and lower anterior teeth. The treatment combined esthetic crown lengthening, dental bleaching, and restorative dentistry using CAD/CAM veneer. The 6-month follow-up examination confirmed the stability of the modification and absence of adverse effects.

  6. Esthetic Rehabilitation through Crown Lengthening Surgery and Conservative CAD/CAM Veneers: A Multidisciplinary Case Report

    Directory of Open Access Journals (Sweden)

    Leandro Passos

    2016-01-01

    Full Text Available This case report describes a successful multidisciplinary approach used to improve the smile esthetics of a patient presenting with excessive gingival display, asymmetric gingival margins, and small upper anterior teeth and lower anterior teeth. The treatment combined esthetic crown lengthening, dental bleaching, and restorative dentistry using CAD/CAM veneer. The 6-month follow-up examination confirmed the stability of the modification and absence of adverse effects.

  7. Esthetic Rehabilitation through Crown Lengthening Surgery and Conservative CAD/CAM Veneers: A Multidisciplinary Case Report.

    Science.gov (United States)

    Passos, Leandro; Soares, Fernando Peixoto; Gallo, Mauricio

    2016-01-01

    This case report describes a successful multidisciplinary approach used to improve the smile esthetics of a patient presenting with excessive gingival display, asymmetric gingival margins, and small upper anterior teeth and lower anterior teeth. The treatment combined esthetic crown lengthening, dental bleaching, and restorative dentistry using CAD/CAM veneer. The 6-month follow-up examination confirmed the stability of the modification and absence of adverse effects. PMID:27668099

  8. ATRX mutations and glioblastoma: Impaired DNA damage repair, alternative lengthening of telomeres, and genetic instability.

    Science.gov (United States)

    Koschmann, Carl; Lowenstein, Pedro R; Castro, Maria G

    2016-05-01

    Alpha thalassemia/mental retardation syndrome X-linked (ATRX) is mutated in nearly a third of pediatric glioblastoma (GBM) patients. We developed an animal model of ATRX-deficient GBM. Using this model combined with analysis of multiple human glioma genome-wide datasets, we determined that ATRX mutation leads to genetic instability, impaired non-homologous end joining, and alternate lengthening of telomeres (ALT). PMID:27314101

  9. Distinct Roles of TRF1 in the Regulation of Telomere Structure and Lengthening*S⃞

    OpenAIRE

    Okamoto, Keiji; Iwano, Tomohiko; Tachibana, Makoto; Shinkai, Yoichi

    2008-01-01

    The telomere is a functional chromatin structure that consists of G-rich repetitive sequences and various associated proteins. Telomeres protect chromosomal ends from degradation, provide escape from the DNA damage response, and regulate telomere lengthening by telomerase. Multiple proteins that localize at telomeres form a complex called shelterin/telosome. One component, TRF1, is a double-stranded telomeric DNA binding protein. Inactivation of TRF1 disrupts telomeric...

  10. Alternative lengthening of telomeres pathway: recombination-mediated telomere maintenance mechanism in human cells.

    OpenAIRE

    Nabetani, Akira; Ishikawa, Fuyuki

    2011-01-01

    Unlimitedly proliferating cells need to acquire the telomere DNA maintenance mechanism, to counteract possible shortening through multiple rounds of replication and segregation of linear chromosomes. Most human cancer cells express telomerase whereas the other cells utilize the alternative lengthening of telomeres (ALT) pathway to elongate telomere DNA. It is suggested that ALT depends on the recombination between telomere repetitive DNAs. However, the molecular details remain unknown. Recent...

  11. Alternative lengthening of telomeres (ALT) in cancer stem cells in vivo

    OpenAIRE

    Bojovic, Bojana; Booth, Ryan E.; Jin, Yi; Zhou, Xiaofeng; Crowe, David L.

    2014-01-01

    Chromosome ends are protected by telomeres which prevent DNA damage response and degradation. Telomerase expression extends telomeres and inhibits DNA damage response. Telomeres are also maintained by the recombination based alternative lengthening pathway. Telomerase is believed to be the sole mechanism for telomere maintenance in epidermis. We show that basal cells in epidermis maintain telomeres both by telomerase and ALT mechanisms in vivo. ALT was detected in epidermal stem cells in Terc...

  12. Suppression of the alternative lengthening of telomere pathway by the chromatin remodelling factor ATRX

    OpenAIRE

    Clynes, David; Jelinska, Clare; Xella, Barbara; Ayyub, Helena; Scott, Caroline; Mitson, Matthew; Taylor, Stephen; Higgs, Douglas R.; Gibbons, Richard J.

    2015-01-01

    Fifteen per cent of cancers maintain telomere length independently of telomerase by the homologous recombination (HR)-associated alternative lengthening of telomeres (ALT) pathway. A unifying feature of these tumours are mutations in ATRX. Here we show that expression of ectopic ATRX triggers a suppression of the pathway and telomere shortening. Importantly ATRX-mediated ALT suppression is dependent on the histone chaperone DAXX. Re-expression of ATRX is associated with a reduction in replica...

  13. Alternative Lengthening of Telomeres is characterized by reduced compaction of telomeric chromatin.

    OpenAIRE

    Episkopou, Charikleia; Draskovic, Irena; Van Beneden, Amandine; Tilman, Gaëlle; Mattiussi, Marina; Gobin, Matthieu; Arnoult, Nausica; Londoño-Vallejo, Arturo; Decottignies, Anabelle

    2014-01-01

    International audience Proper telomeric chromatin configuration is thought to be essential for telomere homeostasis and stability. Previous studies in mouse suggested that loss of heterochromatin marks at telomeres might favor onset of Alternative Lengthening of Telomeres (ALT) pathway, by promoting homologous recombination. However, analysis of chromatin status at human ALT telomeres has never been reported. Here, using isogenic human cell lines and cellular hybrids, which rely either on ...

  14. Alternative mechanisms of telomere lengthening: permissive mutations, DNA repair proteins and tumorigenic progression

    OpenAIRE

    Sandy Gocha1, April Renee; Harris, Julia; Groden, Joanna

    2012-01-01

    Telomeres protect chromosome termini to maintain genomic stability and regulate cellular lifespan. Maintenance of telomere length is required for neoplastic cells after the acquisition of mutations that deregulate cell cycle control and increase cellular proliferation, and can occur through expression of the enzyme telomerase or in a telomerase-independent manner termed alternative lengthening of telomeres (ALT). The precise mechanisms that govern the activation of ALT or telomerase in tumor ...

  15. Topoisomerase IIIα is required for normal proliferation and telomere stability in alternative lengthening of telomeres

    OpenAIRE

    Temime-Smaali, Nassima; Guittat, Lionel; Wenner, Thomas; Bayart, Emilie; Douarre, Céline; Gomez, Dennis; Giraud-Panis, Marie-Josèphe; Londono-Vallejo, Arturo; Gilson, Eric; Amor-Guéret, Mounira; Riou, Jean-François

    2008-01-01

    Topoisomerase (Topo) IIIα associates with BLM helicase, which is proposed to be important in the alternative lengthening of telomeres (ALT) pathway that allows telomere recombination in the absence of telomerase. Here, we show that human Topo IIIα colocalizes with telomeric proteins at ALT-associated promyelocytic bodies from ALT cells. In these cells, Topo IIIα immunoprecipitated with telomere binding protein (TRF) 2 and BLM and was shown to be associated with telomeric DNA by chromatin immu...

  16. The roles of WRN and BLM RecQ helicases in the Alternative Lengthening of Telomeres

    OpenAIRE

    Mendez-Bermudez, Aaron; Hidalgo-Bravo, Alberto; Cotton, Victoria E.; Gravani, Athanasia; Jeyapalan, Jennie N.; Royle, Nicola J.

    2012-01-01

    Approximately 10% of all cancers, but a higher proportion of sarcomas, use the recombination-based alternative lengthening of telomeres (ALT) to maintain telomeres. Two RecQ helicase genes, BLM and WRN, play important roles in homologous recombination repair and they have been implicated in telomeric recombination activity, but their precise roles in ALT are unclear. Using analysis of sequence variation present in human telomeres, we found that a WRN– ALT+ cell line lacks the class of complex...

  17. Pilocytic Astrocytomas Have Telomere-Associated Promyelocytic Leukemia Bodies without Alternatively Lengthened Telomeres

    OpenAIRE

    Slatter, Tania; Gifford-Garner, Jennifer; Wiles, Anna; Tan, Xin; Chen, Yu-Jen; MacFarlane, Martin; Sullivan, Michael; Royds, Janice; Hung, Noelyn

    2010-01-01

    Telomere maintenance by either telomerase activity or the recombination-mediated alternative lengthening of telomeres (ALT) mechanism is a hallmark of cancer. Tumors that use ALT as their telomere maintenance mechanism are characterized by long telomeres of great heterogeneity in length and by specific nuclear structures of co-localized promyelocytic leukemia protein and telomere DNA, called ALT-associated promyelocytic leukemia bodies (APBs). Recent advances have revealed a direct role for A...

  18. Rapid induction of Alternative Lengthening of Telomeres by depletion of the histone chaperone ASF1

    OpenAIRE

    O'Sullivan, Roderick J; Arnoult, Nausica; Daniel H Lackner; Oganesian, Liana; Haggblom, Candy; Corpet, Armelle; Almouzni, Genevieve; Karlseder, Jan

    2014-01-01

    The mechanism of activation of the Alternative Lengthening of Telomeres (ALT) pathway of mammalian chromosome end maintenance has remained an unresolved issue. We have discovered that co-depletion of the histone chaperones ASF1a and ASF1b in human cells induced all hallmarks of ALT in both primary and cancer cells. These included the formation of ALT associated PML bodies (APBs), extra-chromosomal telomeric DNA species an elevated frequency of telomeric sister chromatid exchanges (t-SCE) even...

  19. Sudden Telomere Lengthening Triggers a Rad53-dependent Checkpoint in Saccharomyces cerevisiae

    OpenAIRE

    Viscardi, Valeria; Baroni, Enrico; Romano, Michele; Lucchini, Giovanna; Longhese, Maria Pia

    2003-01-01

    Telomeres are specialized functional complexes that ensure chromosome stability by protecting chromosome ends from fusions and degradation and avoiding chromosomal termini from being sensed as DNA breaks. Budding yeast Tel1 is required both for telomere metabolism and for a Rad53-dependent checkpoint responding to unprocessed double-strand breaks. We show that overexpression of a GAL1-TEL1 fusion causes transient telomere lengthening and activation of a Rad53-dependent...

  20. Alternative Lengthening of Telomeres Renders Cancer Cells Hypersensitive to ATR Inhibitors

    OpenAIRE

    Flynn, Rachel Litman; Cox, Kelli E.; Jeitany, Maya; Wakimoto, Hiroaki; Bryll, Alysia R.; Ganem, Neil J.; Bersani, Francesca; Pineda, Jose R.; Suvà, Mario L.; Benes, Cyril H.; Haber, Daniel A.; Boussin, Francois D.; Zou, Lee

    2015-01-01

    Cancer cells rely on telomerase or the alternative lengthening of telomeres (ALT) pathway to overcome replicative mortality. ALT is mediated by recombination and is prevalent in a subset of human cancers, yet whether it can be exploited therapeutically remains unknown. Loss of the chromatin remodeling protein ATRX associates with ALT in cancers. Here, we show that ATRX loss compromises cell-cycle regulation of the telomeric non-coding RNA TERRA and leads to persistent association of replicati...

  1. Esthetic Rehabilitation through Crown Lengthening Surgery and Conservative CAD/CAM Veneers: A Multidisciplinary Case Report

    Science.gov (United States)

    Soares, Fernando Peixoto; Gallo, Mauricio

    2016-01-01

    This case report describes a successful multidisciplinary approach used to improve the smile esthetics of a patient presenting with excessive gingival display, asymmetric gingival margins, and small upper anterior teeth and lower anterior teeth. The treatment combined esthetic crown lengthening, dental bleaching, and restorative dentistry using CAD/CAM veneer. The 6-month follow-up examination confirmed the stability of the modification and absence of adverse effects.

  2. INFLUENCE OF SHORTENED AND LENGTHENED IMMOBILIZATION ON RAT SOLEUS MUSCLE ATROPHY

    Institute of Scientific and Technical Information of China (English)

    邢国刚; 樊小力; 吴苏娣; 宋新爱; 朱保恭; 唐斌

    2001-01-01

    Objective: To study the possible mechanism and prevention of disuse muscle atrophy. Methods: The shortened immobilization (plaster fixation) of rat' s soleus muscle (SOL) was used as the model of muscle and the lengthened immobilization of rat' s SOL muscle as "passive stretch" method. Types of skeletal muscle fibers were differentiated with m - ATPase staining technique. The changes of rat' s SOL muscle weight (wet weight) as well as the types and the mean cross - sectional area (CSA) of muscle fibers were examined respectively on day 2, 4,7, 14 and 21 under both shortened and lengthened immobilization and then the effect of passive stretch on soleus muscle atrophy in immobilized rats was observed. Results: When shortened immobilization was applied for 4 days, SOL muscle weight (wet weight) became lighter; the fiber crosssectional area (CSA) shrank and type Ⅰ muscle fibers started transforming into type Ⅱ, which all indicated immobilized muscles began to atrophy and as immobilization proceeded, muscle atrophy proceeded toward higher level. In contrast to that, when lengthened immobilization was applied, SOL muscle didn' t show any sign of atrophy until 7th day, and reached its highest level on day 14 and maintained that level even though immobilization continued. Conclusion: From the results, we conclude that passive stretch can either relieve or defer disuse muscle atrophy.

  3. Changes in H-reflex amplitude to muscle stretch and lengthening in humans.

    Science.gov (United States)

    Budini, Francesco; Tilp, Markus

    2016-07-01

    Spinal reflex excitability is traditionally assessed to investigate neural adjustments that occur during human movement. Different experimental procedures are known to condition spinal reflex excitability. Among these, lengthening movements and static stretching the human triceps have been investigated over the last 50 years. The purpose of this review is to shed light on several apparent incongruities in terms of magnitude and duration of the reported results. In the present review dissimilarities in neuro-spinal changes are examined in relation to the methodologies applied to condition and measure them. Literature that investigated three different conditioning procedures was reviewed: passive dorsiflexion, active dorsiflexion through antagonists shortening and eccentric plantar-flexors contractions. Measurements were obtained before, during and after lengthening or stretching. Stimulation intensities and time delays between conditioning procedures and stimuli varied considerably. H-reflex decreases immediately as static stretching is applied and in proportion to the stretch degree. During dorsiflexions the inhibition is stronger with greater dorsiflexion angular velocity and at lower nerve stimulation intensities, while it is weaker if any concomitant muscle contraction is performed. Within 2 s after a single passive dorsiflexion movement, H-reflex is strongly inhibited, and this effect disappears within 15 s. Dorsiflexions repeated over 1 h and prolonged static stretching training induce long-lasting inhibition. This review highlights that the apparent disagreement between studies is ascribable to small methodological differences. Lengthening movements and stretching can strongly influence spinal neural pathways. Results interpretation, however, needs careful consideration of the methodology applied. PMID:27089411

  4. Posterior Cruciate Ligament (pcl) Reconstruction by Transtibial Tunnel:. Suggestions of Lengthening and Slippage Ratio

    Science.gov (United States)

    Kim, Jay-Jung; Kim, Cheol-Woong

    This paper examined the biomechanical fatigue behavior of Achilles tendon autograft after posterior cruciate ligament (PLC) reconstructions. It experimented with various fixation devices and locations on the degree of initial lengthening and slippage to investigate the relationship between lengthening and slippage ratios among calcaneal and soft tissue fixation methods. Eight specimens of proximal tibia and Achilles tendon grafts were harvested from cadavers and classified into four groups according to the type of transtibial fixation technique. A cyclic load ranging from 50N to 250N was applied to each graft when fixed to the proximal tibia at 55 degrees. The soft tissue fixation method, which uses an interference screw, demonstrated a 56.4% ratio of slippage to total elongation. The use of a double cross-pin with the same method demonstrated a 45.4% slippage ratio. The former was associated with approximately 2 mm less total elongation and 13% more slippage than lengthening compared to the latter. This result was predominantly due to the poor standard of fixation compared to the same method using a double cross-pin.

  5. Harmine lengthens circadian period of the mammalian molecular clock in the suprachiasmatic nucleus.

    Science.gov (United States)

    Kondoh, Daisuke; Yamamoto, Saori; Tomita, Tatsunosuke; Miyazaki, Koyomi; Itoh, Nanako; Yasumoto, Yuki; Oike, Hideaki; Doi, Ryosuke; Oishi, Katsutaka

    2014-01-01

    The circadian clock is a cell-autonomous endogenous system that generates circadian rhythms in the behavior and physiology of most organisms. We previously reported that the harmala alkaloid, harmine, lengthens the circadian period of Bmal1 transcription in NIH 3T3 fibroblasts. Clock protein dynamics were examined using real-time reporter assays of PER2::LUC to determine the effects of harmine on the central clock in the suprachiasmatic nucleus (SCN). Harmine significantly lengthened the period of PER2::LUC expression in embryonic fibroblasts, in neuronal cells differentiated from neuronal progenitor cells and in SCN slices obtained from PER2::LUC mice. Although harmine did not induce the transient mRNA expression of clock genes such as Per1, Per2 and Bmal1 in embryonic fibroblasts, it significantly extended the half-life of PER2::LUC protein in neuronal cells and SCN slices. Harmine might lengthen the circadian period of the molecular clock by increasing PER2 protein stability in the SCN.

  6. Association of Interleukin-6 Signalling with the Muscle Stem Cell Response Following Muscle-Lengthening Contractions in Humans

    OpenAIRE

    McKay, Bryon R.; Michael De Lisio; Johnston, Adam P. W.; Ciara E O'Reilly; Phillips, Stuart M.; Tarnopolsky, Mark A.; Gianni Parise

    2009-01-01

    BACKGROUND: The regulation of muscle stem cells in humans in response to muscle injury remains largely undefined. Recently, interleukin-6 (IL-6) has been implicated in muscle stem cell (satellite cell)-mediated muscle hypertrophy in animals; however, the role of IL-6 in the satellite cell (SC) response following muscle-lengthening contractions in humans has not been studied. METHODOLOGY/PRINCIPAL FINDINGS: Eight subjects (age 22+/-1 y; 79+/-8 kg) performed 300 maximal unilateral lengthening c...

  7. Loss of Wild-Type ATRX Expression in Somatic Cell Hybrids Segregates with Activation of Alternative Lengthening of Telomeres

    OpenAIRE

    Kylie Bower; Napier, Christine E.; Cole, Sara L.; Dagg, Rebecca A.; Lau, Loretta M. S.; Duncan, Emma L; Moy, Elsa L.; Reddel, Roger R

    2012-01-01

    Alternative Lengthening of Telomeres (ALT) is a non-telomerase mechanism of telomere lengthening that occurs in about 10% of cancers overall and is particularly common in astrocytic brain tumors and specific types of sarcomas. Somatic cell hybridization analyses have previously shown that normal telomerase-negative fibroblasts and telomerase-positive immortalized cell lines contain repressors of ALT activity, indicating that activation of ALT results from loss of one or more unidentified repr...

  8. [Distraction osteogenesis of deficient alveolar bone prior to dental rehabilitation].

    Science.gov (United States)

    Shilo, D; Emodi, O; Aizenbud, D; Rachmiel, A

    2015-07-01

    Implant supported rehabilitation has become very common in treatment plans nowadays, yet many patients lack the vertical and horizontal bone dimensions required for endosseous implant insertion. Distraction osteogenesis is a technique in which bone is generated by progressive elongation of two bone fragments following an osteotomy or corticotomy. Distraction osteogenesis of the alveolar ridge as a treatment modality in implant dentistry is a very useful technique that allows for adequate bone formation suitable for implant insertion. Alveolar distraction can be unidirectional, bidirectional, multidirectional or horizontal. Alveolar distraction osteogenesis can be performed by using intraosseous distraction devices, intraosseous distraction implants or by extraosseous devices which are the most prevalent today. Distraction osteogenesis has many advantages such as gradual lengthening of the bone with no need for an autogenous bone graft and lack of the associated donor site morbidity as well as distraction of the surrounding soft tissue together with the transported bone. One of the major challenges when using alveolar distraction osteogenesis is controlling the vector of distraction, this problem should be further addressed in future researches. We describe different methods for alveolar distraction osteogenesis, including the surgical procedure, latency period, lengthening and consolidation period. We also discuss the advantages, disadvantages and complications of the method. In this manuscript a case of mandibular alveolar deficiency following mandibular fracture and loss of teeth and the alveolar bone is presented. This patient was treated by alveolar distraction osteogenesis with excellent results. This patient was later rehabilitated . using endosseous implants as demonstrated by radiographs. Alveolar distraction osteogenesis provides a method to regain both hard tissue and soft tissue without additional grafting and is an efficient modality in cases of medium

  9. Bone Densitometry (Bone Density Scan)

    Science.gov (United States)

    ... of DXA Bone Densitometry? What is a Bone Density Scan (DXA)? Bone density scanning, also called dual-energy x-ray absorptiometry ( ... is today's established standard for measuring bone mineral density (BMD). An x-ray (radiograph) is a noninvasive ...

  10. Low Bone Density

    Science.gov (United States)

    ... Density Exam/Testing › Low Bone Density Low Bone Density Low bone density is when your bone density ... people with normal bone density. Detecting Low Bone Density A bone density test will determine whether you ...

  11. The MAGEC system for spinal lengthening in children with scoliosis: A NICE Medical Technology Guidance.

    Science.gov (United States)

    Jenks, Michelle; Craig, Joyce; Higgins, Joanne; Willits, Iain; Barata, Teresa; Wood, Hannah; Kimpton, Christine; Sims, Andrew

    2014-12-01

    Scoliosis-structural lateral curvature of the spine-affects around four children per 1,000. The MAGEC system comprises a magnetically distractible spinal rod implant and an external remote controller, which lengthens the rod; this system avoids repeated surgical lengthening. Rod implants brace the spine internally and are lengthened as the child grows, preventing worsening of scoliosis and delaying the need for spinal fusion. The Medical Technologies Advisory Committee at the National Institute for Health and Care Excellence (NICE) selected the MAGEC system for evaluation in a NICE medical technologies guidance. Six studies were identified by the sponsor (Ellipse Technologies Inc.) as being relevant to the decision problem. Meta-analysis was used to compare the clinical evidence results with those of one conventional growth rod study, and equal efficacy of the two devices was concluded. The key weakness was selection of a single comparator study. The External Assessment Centre (EAC) identified 16 conventional growth rod studies and undertook meta-analyses of relevant outcomes. Its critique highlighted limitations around study heterogeneity and variations in baseline characteristics and follow-up duration, precluding the ability to draw firm conclusions. The sponsor constructed a de novo costing model showing that MAGEC rods generated cost savings of £9,946 per patient after 6 years, compared with conventional rods. The EAC critiqued and updated the model structure and inputs, calculating robust cost savings of £12,077 per patient with MAGEC rods compared with conventional rods over 6 years. The year of valuation was 2012. NICE issued a positive recommendation as supported by the evidence (Medical Technologies Guidance 18). PMID:25172432

  12. Mechanical Characteristics of a Polymer Spring Device used to Lengthen Small Intestine

    Science.gov (United States)

    Steinberger, Douglas J.

    Short Bowel Syndrome (SBS) is a condition that occurs due to an insufficient amount of small intestine needed for nutrient absorption and water regulation of the body. A compression spring device is being developed in order to provide a mechanical stimulus to the tissue, as this type of force has been shown to promote lengthening of the tissue. The research completed in this thesis investigated the mechanical characteristics of the spring device and attempted to relate it to the functionality in rat and porcine intestinal tissue. Results from the evaluation of the springs show that Poly(epsilon-caprolactone), or PCL, is a sufficient polymer to use for creating a biodegradable device as the spring dimensions can be adjusted through variations in the diameter, thickness, and band size in order to provide an adequate spring constant for multiple animal types. Design of the springs, however, need to take into account the size of the gelatin capsule used, the amount of plastic deformation and creep behavior of the spring under compression for an extended time period, and the variation in the mechanical properties of the animal soft tissue that requires lengthening. Integration of the spring in-continuity requires a feature that will provide a mechanical resistance to force that is greater than the force of the spring in the compressed state. The spring still requires further development and any design should also take into account the possibility of intestinal perforations or obstructions. The polymer spring device provides a good means towards developing a treatment option for SBS, and other potential soft tissue lengthening needs of the body.

  13. Monitoring of bone regeneration process by means of texture analysis

    International Nuclear Information System (INIS)

    An image analysis method is proposed for the monitoring of the regeneration of the tibial bone. For this purpose, 130 digitized radiographs of 13 patients, who had undergone tibial lengthening by the Ilizarov method, were studied. For each patient, 10 radiographs, taken at an equal number of postoperative successive time moments, were available. Employing available software, 3 Regions Of Interest (ROIs), corresponding to the: (a) upper, (b) central, and (c) lower aspect of the gap, where bone regeneration was expected to occur, were determined on each radiograph. Employing custom developed algorithms: (i) a number of textural features were generated from each of the ROIs, and (ii) a texture-feature based regression model was designed for the quantitative monitoring of the bone regeneration process. Statistically significant differences (p 2 = 0.9, p < 0.001). The suggested method may contribute to the monitoring of the tibial bone regeneration process.

  14. An analysis on forced eruption in crown lengthening of un-restorable teeth

    Directory of Open Access Journals (Sweden)

    Vahid A

    2004-07-01

    Full Text Available Cervical third root defects, like perforations (due to resoption or iatrogeic, fractures or invasive decays make great difficulties for appropriate restoration making. In these circumstances crown lengthening is needed, especially for anterior teeth. Forced eruption also could be a beneficial treatment. By this therapy, cervical third root defects will be available to receive a good restoration. without gum and biologic width problems. In this article tried to introduce this method of therapy by reviewing litraure and with regard to personal research.

  15. Joint Angular Velocity in Spastic Gait and the Influence of Muscle-Tendon Lengthening*

    Science.gov (United States)

    GRANATA, KEVIN P.; ABEL, MARK F.; DAMIANO, DIANE L.

    2006-01-01

    Background Joint angular velocity (the rate of flexion and extension of a joint) is related to the dynamics of muscle activation and force generation during walking. Therefore, the goal of this research was to examine the joint angular velocity in normal and spastic gait and changes resulting from muscle-tendon lengthening (recession and tenotomy) in patients who have spastic cerebral palsy. Methods The gait patterns of forty patients who had been diagnosed with spastic cerebral palsy (mean age, 8.3 years; range, 3.7 to 14.8 years) and of seventy-three age-matched, normally developing subjects were evaluated with three-dimensional motion analysis and electromyography. The patients who had cerebral palsy were evaluated before muscle-tendon lengthening and nine months after treatment. Results The gait patterns of the patients who had cerebral palsy were characterized by increased flexion of the knee in the stance phase, premature plantar flexion of the ankle, and reduced joint angular velocities compared with the patterns of the normally developing subjects. Even though muscle-tendon lengthening altered sagittal joint angles in gait, the joint angular velocities were generally unchanged at the hip and knee. Only the ankle demonstrated modified angular velocities, including reduced dorsiflexion velocity at foot-strike and improved dorsiflexion velocity through midstance, after treatment. Electromyographic changes included reduced amplitude of the gastrocnemius-soleus during the loading phase and decreased knee coactivity (the ratio of quadriceps and hamstring activation) at toe-off. Principal component analyses showed that, compared with joint-angle data, joint angular velocity was better able to discriminate between the gait patterns of the normal and cerebral palsy groups. Conclusions This study showed that muscle-tendon lengthening corrects biomechanical alignment as reflected by changes in sagittal joint angles. However, joint angular velocity and

  16. Fixator-Assisted Lengthening and Deformity Correction Over an Intramedullary Nail in a Patient with Achondroplasia

    Directory of Open Access Journals (Sweden)

    Erdal Uzun

    2014-12-01

    Full Text Available Achondroplasia is the most frequently encountered form of nonlethal skeletal dysplasia and a type of rhizomelic dwarfism. It results in considerable physical and psychologic handicaps owing to the disproportionate stature of the body and difficulty in performing routine activities of daily living. They also have major musculoskeletal problems including symptomatic malalignment of the lower limbs. Limb lengthening has been used in patients with achondroplasia by different techniques (Intramedullar nailing, monolateral or circular external fixator. We report our treatment of a patient 17 years of age with achondroplasia for bilateral lower limb length discrepancy and bilateral tibial varus deformity.

  17. Crown lengthening procedure following intentional endodontic therapy for correction of supra-erupted posterior teeth: Case series with long-term follow-up

    Directory of Open Access Journals (Sweden)

    Shruti Arun Patil

    2016-01-01

    Full Text Available Context: The crown lengthening procedure (CLP is routinely carried out to correct gingival levels and achieve esthetic contours and adequate crown lengths for restorative purposes. Though the short-term outcomes have been found to be stable, long-term results are not much reported. Aims: To evaluate the long-term stability of the marginal bone levels, gingival levels, and the status of the teeth, which underwent endodontic therapy, followed by CLP and final restorations. Settings and Design: Institutional setting, long-term case series. Materials and Methods: Case records of the patients who underwent CLP and endodontic therapy for corrections of the supra-erupted teeth to regain the lost interocclusal spaces were retrieved, and the cases with complete set of the clinical and radiographs were taken. All the cases were recalled and bone levels on the radiographs, bleeding on probing, probing pocket depths, and changes in the soft tissue margins were evaluated. Statistical Analysis Used: Descriptive analysis. Results: A total of 25 teeth had undergone CLP and endodontic therapy and final restorations for a minimum of 24 months. The mean post-restorative duration was 50.8 ± 22.48 months (range 24–96 months. All the teeth were functional and asymptomatic with 100% survival. Interdental bone loss of 1 mm, probing pockets of 5 mm, and 1 mm buccal recession were observed in 16% of the sites. The amount of interocclusal space regained was adequate to restore the missing teeth in the opposing arch. Conclusions: The CLP is a predictive procedure for correction of supra-erupted teeth. The survival of the teeth that underwent the procedure in the present study was 100% over 24–96 months.

  18. Bone Cancer

    Science.gov (United States)

    ... cancer. Surgery is often the main treatment for bone cancer. Other treatments may include amputation, chemotherapy, and radiation therapy. Because bone cancer can come back after treatment, regular follow-up visits are important. NIH: National ...

  19. Odontoplasty associated with clinical crown lengthening in management of extensive crown destruction

    Directory of Open Access Journals (Sweden)

    Márcio K da Cruz

    2012-01-01

    Full Text Available Aim: The aim of this study was to evaluate the clinical outcome of teeth submitted to odontoplasty during clinical crown lengthening surgery (CCLS, when compared to their contralateral non-operated teeth. Materials and Methods: Fourteen patients submitted to odontoplasty during CCLS were evaluated according to plaque index, bleeding on probing, probing depth and final restoration outcome (total success, relative success and failure. Results: The mean follow-up period was 13.57 (± 8.00 months, and ranged from 6 to 24 months. Twelve cases presented total success of the final rehabilitation and 2 cases presented relative success. The cases of relative success were due to the necessity for a new periodontal intervention (scalling. No differences were observed with respect to periodontal parameters (P>0.05 and the patients that showed relative success presented generalized poor oral hygiene. Conclusions: The odontoplasty during clinical crown lengthening surgery is a feasible procedure in the management of extensive crown destruction.

  20. A comprehensive approach to long-standing facial paralysis based on lengthening temporalis myoplasty.

    Science.gov (United States)

    Labbè, D; Bussu, F; Iodice, A

    2012-06-01

    Long-standing peripheral monolateral facial paralysis in the adult has challenged otolaryngologists, neurologists and plastic surgeons for centuries. Notwithstanding, the ultimate goal of normality of the paralyzed hemi-face with symmetry at rest, and the achievement of a spontaneous symmetrical smile with corneal protection, has not been fully reached. At the beginning of the 20(th) century, the main options were neural reconstructions including accessory to facial nerve transfer and hypoglossal to facial nerve crossover. In the first half of the 20(th) century, various techniques for static correction with autologous temporalis muscle and fascia grafts were proposed as the techniques of Gillies (1934) and McLaughlin (1949). Cross-facial nerve grafts have been performed since the beginning of the 1970s often with the attempt to transplant free-muscle to restore active movements. However, these transplants were non-vascularized, and further evaluations revealed central fibrosis and minimal return of function. A major step was taken in the second half of the 1970s, with the introduction of microneurovascular muscle transfer in facial reanimation, which, often combined in two steps with a cross-facial nerve graft, has become the most popular option for the comprehensive treatment of long-standing facial paralysis. In the second half of the 1990s in France, a regional muscle transfer technique with the definite advantages of being one-step, technically easier and relatively fast, namely lengthening temporalis myoplasty, acquired popularity and consensus among surgeons treating facial paralysis. A total of 111 patients with facial paralysis were treated in Caen between 1997 and 2005 by a single surgeon who developed 2 variants of the technique (V1, V2), each with its advantages and disadvantages, but both based on the same anatomo-functional background and aim, which is transfer of the temporalis muscle tendon on the coronoid process to the lips. For a comprehensive

  1. Recombinant human bone morphogenetic protein-2 suspended in fibrin glue enhances bone formation during distraction osteogenesis in rabbits

    Science.gov (United States)

    Li, Yunfeng; Li, Rui; Hu, Jing; Song, Donghui; Jiang, Xiaowen

    2016-01-01

    Introduction Bone morphogenetic protein-2 (BMP-2) has high potential for bone formation, but its in vivo effects are unpredictable due to the short life time. This study was designed to evaluate the effects of recombinant human (rh) BMP-2 suspended in fibrin on bone formation during distraction osteogenesis (DO) in rabbits. Material and methods The in vitro release kinetics of rhBMP-2 suspended in fibrin was tested using an enzyme-linked immunosorbent assay. Unilateral tibial lengthening for 10 mm was achieved in 48 rabbits. At the completion of osteodistraction, vehicle, fibrin, rhBMP-2 or rhBMP-2 suspended in fibrin (rhBMP-2 + fibrin) was injected into the center of the lengthened gap, with 12 animals in each group. Eight weeks later, the distracted callus was examined by histology, micro-CT and biomechanical testing. Radiographs of the distracted tibiae were taken at both 4 and 8 weeks after drug treatment. Results It was found that fibrin prolonged the life span of rhBMP-2 in vitro with sustained release during 17 days. The rhBMP-2 + fibrin treated animals showed the best results in bone mineral density, bone volume fraction, cortical bone thickness by micro-CT evaluation and mechanical properties by the three-point bending test when compared to the other groups (p < 0.05). In histological images, rhBMP-2 + fibrin treatment showed increased callus formation and better gap bridging compared to the other groups. Conclusions The results of this study suggest that fibrin holds promise to be a good carrier of rhBMP-2, and rhBMP-2 suspended in fibrin showed a stronger promoting effect on bone formation during DO in rabbits. PMID:27279839

  2. The Role of ATRX in the Alternative Lengthening of Telomeres (ALT Phenotype

    Directory of Open Access Journals (Sweden)

    João P. Amorim

    2016-09-01

    Full Text Available Telomeres are responsible for protecting chromosome ends in order to prevent the loss of coding DNA. Their maintenance is required for achieving immortality by neoplastic cells and can occur by upregulation of the telomerase enzyme or through a homologous recombination-associated process, the alternative lengthening of telomeres (ALT. The precise mechanisms that govern the activation of ALT or telomerase in tumor cells are not fully understood, although cellular origin may favor one of the other mechanisms that have been found thus far in mutual exclusivity. Specific mutational events influence ALT activation and maintenance: a unifying frequent feature of tumors that acquire this phenotype are the recurrent mutations of the Alpha Thalassemia/Mental Retardation Syndrome X-Linked (ATRX or Death-Domain Associated Protein (DAXX genes. This review summarizes the established criteria about this phenotype: its prevalence, theoretical molecular mechanisms and relation with ATRX, DAXX and other proteins (directly or indirectly interacting and resulting in the ALT phenotype.

  3. The Role of ATRX in the Alternative Lengthening of Telomeres (ALT) Phenotype.

    Science.gov (United States)

    Amorim, João P; Santos, Gustavo; Vinagre, João; Soares, Paula

    2016-01-01

    Telomeres are responsible for protecting chromosome ends in order to prevent the loss of coding DNA. Their maintenance is required for achieving immortality by neoplastic cells and can occur by upregulation of the telomerase enzyme or through a homologous recombination-associated process, the alternative lengthening of telomeres (ALT). The precise mechanisms that govern the activation of ALT or telomerase in tumor cells are not fully understood, although cellular origin may favor one of the other mechanisms that have been found thus far in mutual exclusivity. Specific mutational events influence ALT activation and maintenance: a unifying frequent feature of tumors that acquire this phenotype are the recurrent mutations of the Alpha Thalassemia/Mental Retardation Syndrome X-Linked (ATRX) or Death-Domain Associated Protein (DAXX) genes. This review summarizes the established criteria about this phenotype: its prevalence, theoretical molecular mechanisms and relation with ATRX, DAXX and other proteins (directly or indirectly interacting and resulting in the ALT phenotype). PMID:27657132

  4. Functional crown lengthening surgery in the aesthetic zone; periodontic and prosthodontic considerations.

    Science.gov (United States)

    Patel, Rajiv M; Baker, Paul

    2015-01-01

    Crown lengthening surgery aims to increase the amount of supragingival tooth tissue by resection of the soft and/or hard tissues to enable otherwise unrestorable teeth to be restored by increasing the retention and resistance forms of the teeth. Restoration of the worn dentition may require significant prosthodontic knowledge and skill. A prosthodontist should be involved from the beginning of the management of the patient. A number of key stages should be considered for correct management. Although the periodontist may guide the prosthodontist with regards to what may or may not be possible surgically, the overall treatment plan should be prosthodontically driven. Clinical Relevance: Toothwear of the anterior dentition provides a unique challenge to restore not only function but also to manage the aesthetic demands of the patient. To ensure that the correct outcome is reached, clinicians should be familiar with the normal anatomical proportions and relationships to enable planning and treatment to take place.

  5. Group velocity and pulse lengthening of mismatched laser pulses in plasma channels

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Carl; Benedetti, Carlo; Esarey, Eric; van Tilborg, Jeroen; Leemans, Wim

    2011-07-07

    Analytic solutions are presented to the non-paraxial wave equation describing an ultra-short, low-power, laser pulse propagating in aplasma channel. Expressions for the laser pulse centroid motion and laser group velocity are derived, valid for matched and mismatchedpropagation in a parabolic plasma channel, as well as in vacuum, for an arbitrary Laguerre-Gaussian laser mode. The group velocity of amismatched laser pulse, for which the laser spot size is strongly oscillating, is found to be independent of propagation distance andsignificantly less than that of a matched pulse. Laser pulse lengthening of a mismatched pulse owing to laser mode slippage isexamined and found to dominate over that due to dispersive pulse spreading for sufficiently long pulses. Analytic results are shown tobe in excellent agreement with numerical solutions of the full Maxwell equations coupled to the plasma response. Implications for plasmachannel diagnostics are discussed.

  6. Suppression of the alternative lengthening of telomere pathway by the chromatin remodelling factor ATRX.

    Science.gov (United States)

    Clynes, David; Jelinska, Clare; Xella, Barbara; Ayyub, Helena; Scott, Caroline; Mitson, Matthew; Taylor, Stephen; Higgs, Douglas R; Gibbons, Richard J

    2015-01-01

    Fifteen per cent of cancers maintain telomere length independently of telomerase by the homologous recombination (HR)-associated alternative lengthening of telomeres (ALT) pathway. A unifying feature of these tumours are mutations in ATRX. Here we show that expression of ectopic ATRX triggers a suppression of the pathway and telomere shortening. Importantly ATRX-mediated ALT suppression is dependent on the histone chaperone DAXX. Re-expression of ATRX is associated with a reduction in replication fork stalling, a known trigger for HR and loss of MRN from telomeres. A G-quadruplex stabilizer partially reverses the effect of ATRX, inferring ATRX may normally facilitate replication through these sequences that, if they persist, promote ALT. We propose that defective telomere chromatinization through loss of ATRX promotes the persistence of aberrant DNA secondary structures, which in turn present a barrier to DNA replication, leading to replication fork stalling, collapse, HR and subsequent recombination-mediated telomere synthesis in ALT cancers. PMID:26143912

  7. The Role of ATRX in the Alternative Lengthening of Telomeres (ALT) Phenotype

    Science.gov (United States)

    Amorim, João P.; Santos, Gustavo; Vinagre, João; Soares, Paula

    2016-01-01

    Telomeres are responsible for protecting chromosome ends in order to prevent the loss of coding DNA. Their maintenance is required for achieving immortality by neoplastic cells and can occur by upregulation of the telomerase enzyme or through a homologous recombination-associated process, the alternative lengthening of telomeres (ALT). The precise mechanisms that govern the activation of ALT or telomerase in tumor cells are not fully understood, although cellular origin may favor one of the other mechanisms that have been found thus far in mutual exclusivity. Specific mutational events influence ALT activation and maintenance: a unifying frequent feature of tumors that acquire this phenotype are the recurrent mutations of the Alpha Thalassemia/Mental Retardation Syndrome X-Linked (ATRX) or Death-Domain Associated Protein (DAXX) genes. This review summarizes the established criteria about this phenotype: its prevalence, theoretical molecular mechanisms and relation with ATRX, DAXX and other proteins (directly or indirectly interacting and resulting in the ALT phenotype). PMID:27657132

  8. Myofascial force transmission between antagonistic rat lower limb muscles: Effects of single muscle or muscle group lengthening

    NARCIS (Netherlands)

    Meijer, Hanneke J.M; Rijkelijkhuizen, Josina M.; Huijing, Peter A.

    2007-01-01

    Effects of lengthening of the whole group of anterior crural muscles (tibialis anterior and extensor hallucis longus muscles (TA + EHL) and extensor digitorum longus (EDL)) on myofascial interaction between synergistic EDL and TA + EHL muscles, and on myofascial force transmission between anterior c

  9. Reconstructive procedures for segmental resection of bone in giant cell tumors around the knee

    Directory of Open Access Journals (Sweden)

    Aggarwal Aditya

    2007-01-01

    Full Text Available Background: Segmental resection of bone in Giant Cell Tumor (GCT around the knee, in indicated cases, leaves a gap which requires a complex reconstructive procedure. The present study analyzes various reconstructive procedures in terms of morbidity and various complications encountered. Materials and Methods: Thirteen cases (M-six and F-seven; lower end femur-six and upper end tibia -seven of GCT around the knee, radiologically either Campanacci Grade II, Grade II with pathological fracture or Grade III were included. Mean age was 25.6 years (range 19-30 years. Resection arthrodesis with telescoping (shortening over intramedullary nail ( n=5, resection arthrodesis with an intercalary allograft threaded over a long intramedullary nail ( n=3 and resection arthrodesis with intercalary fibular autograft and simultaneous limb lengthening ( n=5 were the procedure performed. Results: Shortening was the major problem following resection arthrodesis with telescoping (shortening over intramedullary nail. Only two patients agreed for subsequent limb lengthening. The rest continued to walk with shortening. Infection was the major problem in all cases of resection arthrodesis with an intercalary allograft threaded over a long intramedullary nail and required multiple drainage procedures. Fusion was achieved after two years in two patients. In the third patient the allograft sequestrated. The patient underwent sequestrectomy, telescoping of fragments and ilizarov fixator application with subsequent limb lengthening. The patient was finally given an ischial weight relieving orthosis, 54 months after the index procedure. After resection arthrodesis with intercalary autograft and simultaneous lengthening the resultant gap (~15cm was partially bridged by intercalary nonvascularized dual fibular strut graft (6-7cm and additional corticocancellous bone graft from ipsilateral patella. Simultaneous limb lengthening with a distal tibial corticotomy was performed on an

  10. [Bone diseases].

    Science.gov (United States)

    Uebelhart, Brigitte; Rizzoli, René

    2016-01-13

    Calcium intake shows a small impact on bone mineral density and fracture risk. Denosumab is a more potent inhibitor of bone resorption than zoledronate. Abaloparatide, PTHrP analog, increases bone mineral density and decreases fracture incidence. Teriparatide could be delivered via a transdermic device. Romosozumab and odanacatib improve calculated bone strength. Sequential or combined treatments with denosumab and teriparatide could be of interest, but not denosumab followed by teriparatide. Fibrous dysplasia, Paget disease and hypophosphatasia are updated, as well as atypical femoral fracture and osteonecrosis of the jaw. PMID:26946704

  11. Management of complex long bone nonunions using limb reconstruction system

    Directory of Open Access Journals (Sweden)

    Hiranya Kumar Seenappa

    2013-01-01

    Full Text Available Background: Management of complex nonunions is difficult due to the presence of infection, deformities, shortening and multiple surgeries in the past. Complex nonunions are traditionally managed by Ilizarov fixation. The disadvantages of Ilizarov are poor patient compliance, inconvenience of the frame and difficult frame construction. We conducted a study on 30 long bone complex nonunions treated by the limb reconstruction system (LRS. Materials and Methods: Between April 2009 and September 2012, we treated 30 cases of complex nonunion of long bone with the LRS. 28 were male and 2 females. Average shortening was 5.06 cm and 14 cases presented with infected implants. Initially we managed with implant removal, radical debridement followed by fixation with the LRS. In 16 cases, corticotomy and lengthening was done. The average duration of treatment was 9.68 months. We compressed the fracture site at the rate of 0.25 mm per day for 1-2 weeks and distracted the corticotomy at the rate of 1 mm/day till lengthening was achieved. Result: The union occurred in 89.28% cases and eradication of infection in 91.66% cases. Average lengthening done was 4.57 cm. We had 79% excellent, 11% good and 10% poor bony result and fnctional result was excellent in 40% cases, good in 50% and failure in 10% cases using ASAMI scoring system. Conclusion: LRS is an alternative to the Ilizarov fixation in their management of complex nonunion of long bones. It is less cumbersome to the patient and more surgeon and patient friendly.

  12. Cortical and spinal excitability during and after lengthening contractions of the human plantar flexor muscles performed with maximal voluntary effort.

    Directory of Open Access Journals (Sweden)

    Daniel Hahn

    Full Text Available This study was designed to investigate the sites of potential specific modulations in the neural control of lengthening and subsequent isometric maximal voluntary contractions (MVCs versus purely isometric MVCs of the plantar flexor muscles, when there is enhanced torque during and following stretch. Ankle joint torque during maximum voluntary plantar flexion was measured by a dynamometer when subjects (n = 10 lay prone on a bench with the right ankle tightly strapped to a foot-plate. Neural control was analysed by comparing soleus motor responses to electrical nerve stimulation (M-wave, V-wave, electrical stimulation of the cervicomedullary junction (CMEP and transcranial magnetic stimulation of the motor cortex (MEP. Enhanced torque of 17 ± 8% and 9 ± 8% was found during and 2.5-3 s after lengthening MVCs, respectively. Cortical and spinal responsiveness was similar to that in isometric conditions during the lengthening MVCs, as shown by unchanged MEPs, CMEPs and V-waves, suggesting that the major voluntary motor pathways are not subject to substantial inhibition. Following the lengthening MVCs, enhanced torque was accompanied by larger MEPs (p ≤ 0.05 and a trend to greater V-waves (p ≤ 0.1. In combination with stable CMEPs, increased MEPs suggest an increase in cortical excitability, and enlarged V-waves indicate greater motoneuronal output or increased stretch reflex excitability. The new results illustrate that neuromotor pathways are altered after lengthening MVCs suggesting that the underlying mechanisms of the enhanced torque are not purely mechanical in nature.

  13. 重度根尖周病变根尖手术同期冠延长术短期疗效观察%Evaluation of Simultaneous Apical Surgery with Crown Lengthening for Severe Apical Diseases in Short-Term

    Institute of Scientific and Technical Information of China (English)

    吴王喜; 陈筑苏; 周磊; 邱钧琦; 刘芳

    2015-01-01

    Objective:To evaluate simultaneous apical surgery with crown lengthening for severe periapical diseases in short-term.Method:The total of 6 patients from Guangdong Provincial Stomatological Hospital from Sep 2013 to Oct 2014, 6 cases with 23 roots with severe periapical lesions were treated using simultaneous apical surgery with crown lengthening for resecting apical lesion,trimming gingival margin,shaping alveolar,improving clinical crown height at the same time, provisional restorations before and after surgeries,then final restorations 3 months after surgeries.Evaluation of bone healing by CBCT,soft tissue healing by PES.Result:Periapical defect filled with new bone,gingival margins and restorations were stable 6 months after surgeries.Conclusion:Simultaneous apical surgery and crown lengthening is a valid treatment to severe periapical diseases.%目的:观察重度根尖周病变患者根尖手术同期联合冠延长术近期的治疗效果。方法:选择2013年9月-2014年10月广东省口腔医院门诊重度根尖周病患者6例,采用根尖手术切除根尖病灶,同期冠延长手术增加临床冠高度,修整龈缘及牙槽脊外形,术前术后临时修复体成型牙龈,术后3个月软硬组织改建稳定,进行永久冠修复,每治疗阶段CBCT评估骨组织愈合情况,PES红色美学评分标准评价软组织转归情况。结果:根尖周病灶骨缺损区新骨充填,龈缘形态稳定,附着龈质地色泽协调,修复体稳定。结论:根尖手术同期冠延长术治疗重度根尖周病临床可行。

  14. Talking Bones.

    Science.gov (United States)

    Johnson, Jaclyn; Kassing, Sharon

    2002-01-01

    Describes cooperation with the Saint Louis Zoo to provide opportunities for elementary school students to learn about bones, how animals move, what they eat, and how much they grow. Uses biofacts which include bones, skulls, and other parts to make the laboratory a hands-on experience for students. (YDS)

  15. Bone Markers

    Science.gov (United States)

    ... bone turnover: C-telopeptide (C-terminal telopeptide of type 1 collagen (CTx)) – a marker for bone resorption. It is ... resorption include: N-telopeptide (N-terminal telopeptide of type 1 collagen (NTx)) – a peptide fragment from the amino terminal ...

  16. Bone densitometry

    DEFF Research Database (Denmark)

    Ravn, Pernille; Alexandersen, P; Møllgaard, A

    1999-01-01

    The bisphosphonates have been introduced as alternatives to hormone replacement therapy (HRT) for the treatment and prevention of postmenopausal osteoporosis. The expected increasing application in at clinical practice demands cost-effective and easily handled methods to monitor the effect on bone....... The weak response at the distal forearm during antiresorptive treatment has restricted the use of bone densitometry at this region. We describe a new model for bone densitometry at the distal forearm, by which the response obtained is comparable to the response in other regions where bone densitometry...... is much more expensive and technically complicated. By computerized iteration of single X-ray absorptiometry forearm scans we defined a region with 65% trabecular bone. The region was analyzed in randomized, double-masked, placebo- controlled trials: a 2-year trial with alendronate (n = 69), a 1-year...

  17. Postoperative observation of crown lengthening%牙冠延长术的术后观察

    Institute of Scientific and Technical Information of China (English)

    吕威; 张喆

    2011-01-01

    Objective To investigate the effect and recovery after crown lengthening. Methods Ten patients were performed the crown lengthening, and then the preoperative and the postoperative ( 4 to 6 weeks )inde-xes were observed and compared according to preoperative position of breaking edge on the alveolar ridge crest. These observing indexes were following: ① color, shape, quality and broken ends exposure; ②plaque index ( PLI ), bleeding index ( PLI ) and mobility degree ( MD ) postoperatively; ③position of the ends: distance be-tween the top and the ends of the alveolar ridge and distance between the top of the alveolar ridge and gum; ④position relationship between the anterior gingival margin ( tongue side ) and adjacent gingival margin, the post-operative recovery of gingiva papilla of upper-front teeth. Results Subjective feeling of patients were good with-out sensitive to percussion and gingivitis, gingival margin height was coordinated with adjacent teeth, the X-ray image showed the periodontal and periapical condition, alveolar ridge were normal. Meanwhile, exposure of bro-ken end of tooth root was 1 to 2 mm above gum which is benefit to the appearance and repair. Conclusion Crown lengthening is benefit to preservation and restoration of tooth without enough biological width which their broken ends at the bottom of gum, it is also a good foundation for the health of periodontal through dental restorations.%目的 探讨牙齿牙冠延长术后修复的疗效及恢复情况.方法 对10例患者行牙冠延长术,依术前牙齿断缘位于牙槽嵴顶的位置,观察比较术前及术后4~6周效果,观察指标:①牙龈的色、形、质及断端暴露是否良好;②菌斑指数(PLI) 、出血指数(BI) 和松动度(MD);③断端位置,牙槽嵴顶与断端的距离和牙槽嵴顶与牙龈的距离;④前牙龈缘的位置与相邻牙龈缘的位置关系(唇舌侧),上前牙牙龈乳头的术后恢复情况.结果 患牙主观感觉良好,无叩痛,

  18. 上颌双侧中切牙外伤行冠延长术后的修复设计%Design of bilateral maxillary central incisor prosthesis after surgical crown lengthening

    Institute of Scientific and Technical Information of China (English)

    牛建杰; 杨帆

    2014-01-01

    目的:比较上颌双侧中切牙外伤行冠延长术后,不同修复设计对牙槽骨应力及牙齿动度的影响。方法:通过逆向工程技术建立齿冠延长术后不同骨下降高度的三维有限元模型,并将其设计为单冠、二联冠、三联冠、四联冠修复;然后用三维有限元法分析降低不同牙槽骨高度对桩核冠修复后牙槽骨应力分布及牙齿动度的影响。结果:随着牙槽骨高度的降低,所有修复形式组的牙槽骨应力及牙齿位移都有所上升,其中单冠修复组的增加幅度最大;当骨高度下降1 mm和2 mm时,单冠和3种联冠修复均能满足牙周潜力的要求;而骨下降高度为3 mm时,单冠修复组的应力值超过了牙周潜力的范围,二联冠修复接近牙周潜力,三联冠及四联冠修复均小于牙周潜力。结论:去骨高度在2 mm以内时,单冠和二联冠修复均可,但二联冠可以降低手术后造成的不利影响;当去骨高度为3 mm时,必须采用联冠修复,最好选用三联冠修复。%AIM:To investigate the effects of different prosthetic designs on the alveolar bone stress distri-bution and tooth moblilty of bilateral maxillary central incisors after surgical crown lengthening.METHODS:A three dimensional finite element model(3DFEM)of crowns with different alveolar bone height aroud the bilateral maxillary incisors was established by reverse modeling method.According to the design of prosthesis,the models was divided into 4 groups:single crown,2-unit combined crowns,3-unit combined crowns and 4-unit combined crowns.The alveolar bone stress distribution and terminal mobility with different crown design was analyzed using the 3DFEM.RESULTS:The maximum von Mises stress in the alveolar bone and the terminal mobility of the crown increased with the reduction of alveolar bone height.When the bone height reduced by less than 2 mm,all designs of restorations meet the require-ments of periodontal

  19. Your Bones

    Science.gov (United States)

    ... a fall! If you play sports like football, soccer, lacrosse, or ice hockey, always wear all the ... to strengthen your bones is through exercise like running, jumping, dancing, and playing sports. Take these steps ...

  20. Lengthening of the growing season in wheat and maize producing regions

    Directory of Open Access Journals (Sweden)

    Brigitte Mueller

    2015-09-01

    Full Text Available Human-induced increases in atmospheric greenhouse gas concentrations have led to rising global temperatures. Here we investigate changes in an annual temperature-based index, the growing season length, defined as the number of days with temperature above 5 °C. We show that over extratropical regions where wheat and maize are harvested, the increase in growing season length from 1956 to 2005 can be attributed to increasing greenhouse gas concentrations. Our analyses also show that climate change has increased the probability of extremely long growing seasons by a factor of 25, and decreased the probability of extremely short growing seasons. A lengthening of the growing season in regions with these mostly rain-fed crops could improve yields, provided that water availability does not become an issue. An expansion of areas with more than 150 days of growing season into the northern latitudes makes more land potentially available for planting wheat and maize. Furthermore, double-cropping can become an alternative to current practices in areas with very long growing seasons which are also shown to increase with a warming climate. These results suggest that there is a strong impact of anthropogenic climate change on growing season length. However, in some regions and with further exacerbated climate change, high temperatures may already be or may become a limiting factor for plant productivity.

  1. Comparison of different methods involved in the planning of clinical crown lengthening surgery.

    Science.gov (United States)

    Zanatta, Fabricio Batistin; Giacomelli, Bruno Rodrigues; Dotto, Patricia Pasquali; Fontanella, Vânia Regina Camargo; Rosing, Cassiano Kuchenbecker

    2010-01-01

    There is little material in the literature that compares biological width measurements in periapical and bite-wings radiographs with clinical measurements. The purpose of this study was to compare measurements of biological width taken by three different methods which are frequently used for planning periodontal surgery - periapical radiograph, bite-wing radiograph and transperiodontal probing - with the trans-surgical measurements. Thirty-four sites from twenty-one subjects were analyzed. The intra-class correlation coefficients between measurements obtained trans-surgically (gold standard) and those obtained by transperiodontal probing, periapical radiography and bite-wing radiography were determined. Average measurements were compared using the Wilcoxon test at a significance level of 0.05. Also, the frequency distribution of differences between test measurements and the gold standard was calculated. The results showed that transperiodontal probing (mean 2.05 mm) was the most accurate measurement, as compared to the gold standard (mean 1.97 mm), with no statistically significant difference observed. On the other hand, periapical and bite-wing radiographic mean values (1.56 mm and 1.72 mm, respectively) were smaller than the gold standard, with statistically significant differences (p crown lengthening surgery should, preferably, include transperiodontal probing.

  2. Comparison of different methods involved in the planning of clinical crown lengthening surgery

    Directory of Open Access Journals (Sweden)

    Fabricio Batistin Zanatta

    2010-12-01

    Full Text Available There is little material in the literature that compares biological width measurements in periapical and bite-wings radiographs with clinical measurements. The purpose of this study was to compare measurements of biological width taken by three different methods which are frequently used for planning periodontal surgery - periapical radiograph, bite-wing radiograph and transperiodontal probing - with the trans-surgical measurements. Thirty-four sites from twenty-one subjects were analyzed. The intra-class correlation coefficients between measurements obtained trans-surgically (gold standard and those obtained by transperiodontal probing, periapical radiography and bite-wing radiography were determined. Average measurements were compared using the Wilcoxon test at a significance level of 0.05. Also, the frequency distribution of differences between test measurements and the gold standard was calculated. The results showed that transperiodontal probing (mean 2.05 mm was the most accurate measurement, as compared to the gold standard (mean 1.97 mm, with no statistically significant difference observed. On the other hand, periapical and bite-wing radiographic mean values (1.56 mm and 1.72 mm, respectively were smaller than the gold standard, with statistically significant differences (p < 0.05. It was concluded that transperiodontal probing was the most accurate measurement, as compared to the gold standard, followed by that obtained with the bite-wing radiograph. The clinical relevance of these results could be that planning for crown lengthening surgery should, preferably, include transperiodontal probing.

  3. Alternative lengthening of telomeres: recurrent cytogenetic aberrations and chromosome stability under extreme telomere dysfunction.

    Science.gov (United States)

    Sakellariou, Despoina; Chiourea, Maria; Raftopoulou, Christina; Gagos, Sarantis

    2013-11-01

    Human tumors using the alternative lengthening of telomeres (ALT) exert high rates of telomere dysfunction. Numerical chromosomal aberrations are very frequent, and structural rearrangements are widely scattered among the genome. This challenging context allows the study of telomere dysfunction-driven chromosomal instability in neoplasia (CIN) in a massive scale. We used molecular cytogenetics to achieve detailed karyotyping in 10 human ALT neoplastic cell lines. We identified 518 clonal recombinant chromosomes affected by 649 structural rearrangements. While all human chromosomes were involved in random or clonal, terminal, or pericentromeric rearrangements and were capable to undergo telomere healing at broken ends, a differential recombinatorial propensity of specific genomic regions was noted. We show that ALT cells undergo epigenetic modifications rendering polycentric chromosomes functionally monocentric, and because of increased terminal recombinogenicity, they generate clonal recombinant chromosomes with interstitial telomeric repeats. Losses of chromosomes 13, X, and 22, gains of 2, 3, 5, and 20, and translocation/deletion events involving several common chromosomal fragile sites (CFSs) were recurrent. Long-term reconstitution of telomerase activity in ALT cells reduced significantly the rates of random ongoing telomeric and pericentromeric CIN. However, the contribution of CFS in overall CIN remained unaffected, suggesting that in ALT cells whole-genome replication stress is not suppressed by telomerase activation. Our results provide novel insights into ALT-driven CIN, unveiling in parallel specific genomic sites that may harbor genes critical for ALT cancerous cell growth. PMID:24339742

  4. Alternative Lengthening of Telomeres: Recurrent Cytogenetic Aberrations and Chromosome Stability under Extreme Telomere Dysfunction

    Directory of Open Access Journals (Sweden)

    Despoina Sakellariou

    2013-11-01

    Full Text Available Human tumors using the alternative lengthening of telomeres (ALT exert high rates of telomere dysfunction. Numerical chromosomal aberrations are very frequent, and structural rearrangements are widely scattered among the genome. This challenging context allows the study of telomere dysfunction-driven chromosomal instability in neoplasia (CIN in a massive scale. We used molecular cytogenetics to achieve detailed karyotyping in 10 human ALT neoplastic cell lines.We identified 518 clonal recombinant chromosomes affected by 649 structural rearrangements. While all human chromosomes were involved in random or clonal, terminal, or pericentromeric rearrangements and were capable to undergo telomere healing at broken ends, a differential recombinatorial propensity of specific genomic regions was noted.We show that ALT cells undergo epigenetic modifications rendering polycentric chromosomes functionally monocentric, and because of increased terminal recombinogenicity, they generate clonal recombinant chromosomes with interstitial telomeric repeats. Losses of chromosomes 13, X, and 22, gains of 2, 3, 5, and 20, and translocation/deletion events involving several common chromosomal fragile sites (CFSs were recurrent. Long-term reconstitution of telomerase activity in ALT cells reduced significantly the rates of random ongoing telomeric and pericentromeric CIN. However, the contribution of CFS in overall CIN remained unaffected, suggesting that in ALT cells whole-genome replication stress is not suppressed by telomerase activation. Our results provide novel insights into ALT-driven CIN, unveiling in parallel specific genomic sites that may harbor genes critical for ALT cancerous cell growth.

  5. Sausage Instabilities on top of Kinking Lengthening Current-Carrying Magnetic Flux Tubes

    Science.gov (United States)

    von der Linden, Jens; You, Setthivoine

    2015-11-01

    Observations indicate that the dynamics of magnetic flux tubes in our cosmos and terrestrial experiments involve fast topological change beyond MHD reconnection. Recent experiments suggest that hierarchies of instabilities coupling disparate plasma scales could be responsible for this fast topological change by accessing two-fluid and kinetic scales. This study will explore the possibility of sausage instabilities developing on top of a kink instability in lengthening current-carrying magnetic flux tubes. Current driven flux tubes evolve over a wide range of aspect ratios k and current to magnetic flux ratios λ . An analytical stability criterion and numerical investigations, based on applying Newcomb's variational approach to idealized magnetic flux tubes with core and skin currents, indicate a dependence of the stability boundaries on current profiles and overlapping kink and sausage unstable regions in the k - λ trajectory of the flux tubes. A triple electrode planar plasma gun (Mochi.LabJet) is designed to generate flux tubes with discrete core and skin currents. Measurements from a fast-framing camera and a high resolution magnetic probe are being assembled into stability maps of the k - λ space of flux tubes. This work was sponsored in part by the US DOE Grant DE-SC0010340.

  6. Anthraquinones quinizarin and danthron unwind negatively supercoiled DNA and lengthen linear DNA

    Energy Technology Data Exchange (ETDEWEB)

    Verebová, Valéria [Institute of Biophysics, University of Veterinary Medicine and Pharmacy, Komenského 73, 041 81 Košice (Slovakia); Adamcik, Jozef [Food and Soft Materials Science, Institute of Food, Nutrition and Health, ETH Zurich, Schmelzbergstrasse 9, CH-8092 Zürich (Switzerland); Danko, Patrik; Podhradský, Dušan [Department of Biochemistry, Institute of Chemistry, Faculty of Sciences, P.J. Šafárik University, Moyzesova 11, 041 54 Košice (Slovakia); Miškovský, Pavol [Department of Biophysics, Faculty of Sciences, P.J. Šafárik University, Jesenná 5, 041 54 Košice (Slovakia); Center for Interdisciplinary Biosciences, Faculty of Sciences, P.J. Šafárik University, Jesenná 5, 041 54 Košice (Slovakia); Staničová, Jana, E-mail: jana.stanicova@uvlf.sk [Institute of Biophysics, University of Veterinary Medicine and Pharmacy, Komenského 73, 041 81 Košice (Slovakia)

    2014-01-31

    Highlights: • Anthraquinones quinizarin and danthron unwind negatively supercoiled DNA. • Anthraquinones quinizarin and danthron lengthen linear DNA. • Anthraquinones quinizarin and danthron possess middle binding affinity to DNA. • Anthraquinones quinizarin and danthron interact with DNA by intercalating mode. - Abstract: The intercalating drugs possess a planar aromatic chromophore unit by which they insert between DNA bases causing the distortion of classical B-DNA form. The planar tricyclic structure of anthraquinones belongs to the group of chromophore units and enables anthraquinones to bind to DNA by intercalating mode. The interactions of simple derivatives of anthraquinone, quinizarin (1,4-dihydroxyanthraquinone) and danthron (1,8-dihydroxyanthraquinone), with negatively supercoiled and linear DNA were investigated using a combination of the electrophoretic methods, fluorescence spectrophotometry and single molecule technique an atomic force microscopy. The detection of the topological change of negatively supercoiled plasmid DNA, unwinding of negatively supercoiled DNA, corresponding to appearance of DNA topoisomers with the low superhelicity and an increase of the contour length of linear DNA in the presence of quinizarin and danthron indicate the binding of both anthraquinones to DNA by intercalating mode.

  7. Response to Proximal Restorations Placed Either Subgingivally or Following Crown Lengthening in Patients with No History of Periodontal Disease.

    Science.gov (United States)

    Oppermann, Rui Vicente; Gomes, Sabrina Carvalho; Cavagni, Juliano; Cayana, Ezymar Gomes; Conceição, Ewerton Nocchi

    2016-01-01

    The purpose of this study was to compare the impact of resin restorations placed supragingivally or impinging periodontal biologic width (PBW). Ten patients (aged 19 to 35 years) with at least two contralateral teeth (premolars and molars) in need of proximal subgingival restorations participated. Test group (TG) (impingement of PBW with transsurgical restorations) and control croup (CG) (supragingival restorations after crown lengthening) were randomly assigned. Visible plaque (VP), bleeding on probing (BOP), periodontal probing depth (PPD), and clinical attachment loss (CAL) were evaluated at baseline and at 45, 90, and 180 days, and by transperiodontal probing at baseline and 180 days. Generalized estimating equations, Wald test, and t test were used (P ≤ .05). VP and BOP were reduced and maintained at low levels (less than 10% from day 45 on). PPD initially reduced in the TG. At day 180, no intra- or intergroup differences were observed (P > .05). CAL was higher in the CG after surgery (P crown lengthening.

  8. The Ku subunit of telomerase binds Sir4 to recruit telomerase to lengthen telomeres in S. cerevisiae.

    Science.gov (United States)

    Hass, Evan P; Zappulla, David C

    2015-01-01

    In Saccharomyces cerevisiae and in humans, the telomerase RNA subunit is bound by Ku, a ring-shaped protein heterodimer best known for its function in DNA repair. Ku binding to yeast telomerase RNA promotes telomere lengthening and telomerase recruitment to telomeres, but how this is achieved remains unknown. Using telomere-length analysis and chromatin immunoprecipitation, we show that Sir4 - a previously identified Ku-binding protein that is a component of telomeric silent chromatin - is required for Ku-mediated telomere lengthening and telomerase recruitment. We also find that specifically tethering Sir4 directly to Ku-binding-defective telomerase RNA restores otherwise-shortened telomeres to wild-type length. These findings suggest that Sir4 is the telomere-bound target of Ku-mediated telomerase recruitment and provide one mechanism for how the Sir4-competing Rif1 and Rif2 proteins negatively regulate telomere length in yeast. PMID:26218225

  9. Replication protein A prevents accumulation of single-stranded telomeric DNA in cells that use alternative lengthening of telomeres

    OpenAIRE

    Grudic, Amra; Jul-Larsen, Åsne; Haring, SJ; Wold, MS; Lønning, Per Eystein; Bjerkvig, Rolf; Bøe, Stig Ove

    2007-01-01

    The activation of a telomere maintenance mechanism is required for cancer development in humans. While most tumors achieve this by expressing the enzyme telomerase, a fraction (5–15%) employs a recombination-based mechanism termed alternative lengthening of telomeres (ALT). Here we show that loss of the single-stranded DNA-binding protein replication protein A (RPA) in human ALT cells, but not in telomerase-positive cells, causes increased exposure of single-stranded G-rich telomeric DNA, cel...

  10. Loss of ATRX, Genome Instability, and an Altered DNA Damage Response Are Hallmarks of the Alternative Lengthening of Telomeres Pathway

    OpenAIRE

    Lovejoy, Courtney A.; Wendi Li; Steven Reisenweber; Supawat Thongthip; Joanne Bruno; Titia de Lange; Saurav; Petrini, John H.J.; Sung, Patricia A.; Maria Jasin; Joseph Rosenbluh; Yaara Zwang; Weir, Barbara A.; Charlie Hatton; Elena Ivanova

    2012-01-01

    The Alternative Lengthening of Telomeres (ALT) pathway is a telomerase-independent pathway for telomere maintenance that is active in a significant subset of human cancers and in vitro immortalized cell lines. ALT is thought to involve templated extension of telomeres through homologous recombination, but the genetic or epigenetic changes that unleash ALT are not known. Recently, mutations in the ATRX/DAXX chromatin remodeling complex and histone H3.3 were found to correlate with features of ...

  11. Caenorhabditis elegans POT-2 telomere protein represses a mode of alternative lengthening of telomeres with normal telomere lengths

    OpenAIRE

    Cheng, Chen; Shtessel, Ludmila; Brady, Megan M.; Ahmed, Shawn

    2012-01-01

    Canonical telomere repeats at chromosome termini can be maintained by a telomerase-independent pathway termed alternative lengthening of telomeres (ALT). Human cancers that survive via ALT can exhibit long and heterogeneous telomeres, although many telomerase-negative tumors possess telomeres of normal length. Here, we report that Caenorhabditis elegans telomerase mutants that survived via ALT possessed either long or normal telomere lengths. Most ALT strains displayed end-to-end chromosome f...

  12. HP1-Mediated Formation of Alternative Lengthening of Telomeres-Associated PML Bodies Requires HIRA but Not ASF1a

    OpenAIRE

    Wei-Qin Jiang; Akira Nguyen; Ying Cao; Andy C-M Chang; Reddel, Roger R

    2011-01-01

    Approximately 10% of cancers use recombination-mediated Alternative Lengthening of Telomeres (ALT) instead of telomerase to prevent telomere shortening. A characteristic of cells that utilize ALT is the presence of ALT-associated PML nuclear bodies (APBs) containing (TTAGGG)n DNA, telomere binding proteins, DNA recombination proteins, and heterochromatin protein 1 (HP1). The function of APBs is unknown and it is possible that they are functionally heterogeneous. Most ALT cells lack functional...

  13. Suppression of Alternative Lengthening of Telomeres by Sp100-Mediated Sequestration of the MRE11/RAD50/NBS1 Complex

    OpenAIRE

    Jiang, Wei-Qin; Zhong, Ze-Huai; Henson, Jeremy D.; Neumann, Axel A.; Chang, Andy C.-M.; Reddel, Roger R

    2005-01-01

    Approximately 10% of cancers overall use alternative lengthening of telomeres (ALT) instead of telomerase to prevent telomere shortening, and ALT is especially common in astrocytomas and various types of sarcomas. The hallmarks of ALT in telomerase-negative cancer cells include a unique pattern of telomere length heterogeneity, rapid changes in individual telomere lengths, and the presence of ALT-associated promyelocytic leukemia bodies (APBs) containing telomeric DNA and proteins involved in...

  14. Telomere dysfunction and activation of alternative lengthening of telomeres in B-lymphocytes infected by Epstein–Barr virus

    OpenAIRE

    Kamranvar, S A; Chen, X; Masucci, M G

    2013-01-01

    Malignant cells achieve replicative immortality by two alternative mechanisms, a common one dependent on de novo synthesis of telomeric DNA by telomerase, and a rare one based on telomere recombination known as alternative lengthening of telomeres (ALT). Epstein–Barr virus (EBV) transforms human B-lymphocytes into lymphoblastoid cell lines with unlimited growth potential in vitro and in vivo. Here we show that newly EBV-infected cells exhibit multiple signs of telomere dysfunction, including ...

  15. Break-Induced Replication Requires DNA Damage-Induced Phosphorylation of Pif1 and Leads to Telomere Lengthening

    OpenAIRE

    Yulia Vasianovich; Harrington, Lea A.; Svetlana Makovets

    2014-01-01

    Broken replication forks result in DNA breaks that are normally repaired via homologous recombination or break induced replication (BIR). Mild insufficiency in the replicative ligase Cdc9 in budding yeast Saccharomyces cerevisiae resulted in a population of cells with persistent DNA damage, most likely due to broken replication forks, constitutive activation of the DNA damage checkpoint and longer telomeres. This telomere lengthening required functional telomerase, the core DNA damage signali...

  16. Presence of alternative lengthening of telomeres associated circular extrachromosome telomere repeats in primary leukemia cells of chronic myeloid leukemia

    OpenAIRE

    Samassekou, Oumar; Malina, Abba; Hébert, Josée; Yan, Ju

    2013-01-01

    Background The predominant mechanism by which human tumors maintain telomere length is via telomerase. In ~10% of tumor samples, however, telomere length is conserved, despite no detectable telomerase activity, in part through activation of the alternative lengthening of telomeres (ALT) pathway. Methods We studied the circular extra-chromosomal telomeric repeat (ECTR), an ALT hallmark, and telomerase activity in 24 chronic myeloid leukemia (CML) patients in chronic phase (CP). Results We iden...

  17. A model of a patient-derived IDH1 mutant anaplastic astrocytoma with alternative lengthening of telomeres

    OpenAIRE

    Borodovsky, Alexandra; Meeker, Alan K.; Ewen F Kirkness; Zhao, Qi; Eberhart, Charles G.; Gallia, Gary L.; Riggins, Gregory J.

    2014-01-01

    Mutations in isocitrate dehydrogenase 1 (IDH1) have been found in the vast majority of low grade and progressive infiltrating gliomas and are characterized by the production of 2-hydroxyglutarate from α-ketoglutarate. Recent investigations of malignant gliomas have identified additional genetic and chromosomal abnormalities which cluster with IDH1 mutations into two distinct subgroups. The astrocytic subgroup was found to have frequent mutations in ATRX, TP53 and displays alternative lengthen...

  18. Induction of alternative lengthening of telomeres-associated PML bodies by p53/p21 requires HP1 proteins

    OpenAIRE

    Jiang, Wei-Qin; Zhong, Ze-Huai; Nguyen, Akira; Henson, Jeremy D.; Toouli, Christian D.; Braithwaite, Antony W.; Reddel, Roger R

    2009-01-01

    Alternative lengthening of telomeres (ALT) is a recombination-mediated process that maintains telomeres in telomerase-negative cancer cells. In asynchronously dividing ALT-positive cell populations, a small fraction of the cells have ALT-associated promyelocytic leukemia nuclear bodies (APBs), which contain (TTAGGG)n DNA and telomere-binding proteins. We found that restoring p53 function in ALT cells caused p21 up-regulation, growth arrest/senescence, and a large increase in cells containing ...

  19. Stable expression of promyelocytic leukaemia (PML) protein in telomerase positive MCF7 cells results in alternative lengthening of telomeres phenotype

    OpenAIRE

    Yong Jacklyn W Y; Yeo Xiujun; Khan Md; Lee Martin B; Prakash Hande M

    2012-01-01

    Abstract Background Cancer cells can employ telomerase or the alternative lengthening of telomeres (ALT) pathway for telomere maintenance. Cancer cells that use the ALT pathway exhibit distinct phenotypes such as heterogeneous telomeres and specialised Promyelocytic leukaemia (PML) nuclear foci called APBs. In our study, we used wild-type PML and a PML mutant, in which the coiled-coil domain is deleted (PML C/C-), to investigate how these proteins can affect telomere maintenance pathways in c...

  20. The effects of intramuscular tenotomy on the lengthening characteristics of tibialis posterior: high versus low intramuscular tenotomy

    OpenAIRE

    Altuntas, Altay O.; Dagge, Benjamin; Chin, Terence Y. P.; Palamara, Joseph E. A.; Eizenberg, Norman; Wolfe, Rory; Graham, H. Kerr

    2011-01-01

    Background Lengthening of soft-tissue contractures is frequently required in children with a wide variety of congenital and acquired deformities. However, little is known about the biomechanics of surgical procedures which are commonly used in contracture surgery, or if variations in technique may have a bearing on surgical outcomes. We investigated the hypothesis that the site of intramuscular tenotomy (IMT) within the muscle–tendon-unit (MTU) of the tibialis posterior (TP) would affect the ...

  1. Improving gingival smile by means of guided bone regeneration principles

    Science.gov (United States)

    Ferreira, Carlos Eduardo de Almeida; Brandão, Roberto Carlos Bodart; Martinelli, Carolina Borges; Pignaton, Túlio Bonna

    2016-01-01

    ABSTRACT Objective: This study evaluated the effectiveness of guided bone regeneration (GBR) carried out with xenogenic bone substitute (Bio-OssTM) and collagen resorbable membrane (Bio-GideTM) to improve gingival smile (GS) in patients with excessive vertical maxillary growth (EVMG). Methods: Twelve healthy women aged between 20 and 49 years old (mean age of 26 years), with 5 mm or more of gingival exposure during fully posed smile (FPS) due to EVMG, were included. Baseline digital photographs were taken with standardized head position at rest and FPS. In eight out of 12 cases, crown lengthening procedure was indicated and the initial incision was made 2 to 4 mm from the gingival margin. In four cases, with no indication for crown lengthening procedure, a sulcular incision was performed. GBR was performed in all cases, using micro screws and/or titanium mesh associated with Bio-OssTM and Bio-GideTM. After 10 days, sutures were removed. Recall appointments were scheduled at 1, 6, and 12 months when standardized photographs were again taken. ImageToolTM software was used to measure the gingival exposure (GE) during FPS from the standardized close-up smile photographs at baseline and 12 months. Results: GE mean at baseline was 275.44 mm2. After 12 months, patients who undergone exclusively GBR procedure, presented GE reduction of 40.7%, ∆ = 112.01 mm2 (statistically significant, p = 0.12), and patients who had crown lengthening associated with the graft had a reduction of 60%, ∆ = 167.01 mm2. Conclusion: Our results using GBR to improve GS in cases of EVMG showed an exceptionally high patient acceptance and satisfaction. One-year follow-up confirmed stable results. PMID:27409660

  2. Columella Lengthening with a Full-Thickness Skin Graft for Secondary Bilateral Cleft Lip and Nose Repair

    Science.gov (United States)

    Lee, Yoon Seok; Shin, Dong Hyeok; Choi, Hyun Gon; Kim, Jee Nam; Lee, Myung Chul; Kim, Soon Heum; Kim, Cheol Keun; Jo, Dong In

    2015-01-01

    Background Various techniques for lengthening short columellae have been used for bilateral cleft nose repair. However, previous methods have not yielded satisfactory results. We performed a full-thickness skin graft to lengthen short columellae during secondary cleft nose repair in adult patients. Methods Ten bilateral cleft lip and nose patients underwent secondary cheiloplasty with open rhinoplasty between July 2008 and August 2014. The patients underwent a full-thickness skin graft on the medial crura to elongate the columella. The average age of the patients at the time of surgery was 22.2 years. Nasal profiles were evaluated before and after the operation using the photogrammetric method. Results The nasal profiles were improved in all patients, and all skin grafts were well taken, with the exception of one patient. Columellar height, nostril height, and columella-lip angle increased, and nasal width decreased significantly. The ratios of columellar height to nasal height, columellar height to nasal width, and nasal height to nasal width increased to a statistically significant extent. Conclusions Columella lengthening with a full-thickness skin graft is a simple and effective method for the repair of severely short columellae in bilateral cleft nose patients. We had satisfactory outcomes, with good color matching and aesthetically pleasing contours. PMID:26618116

  3. A model of a patient-derived IDH1 mutant anaplastic astrocytoma with alternative lengthening of telomeres.

    Science.gov (United States)

    Borodovsky, Alexandra; Meeker, Alan K; Kirkness, Ewen F; Zhao, Qi; Eberhart, Charles G; Gallia, Gary L; Riggins, Gregory J

    2015-02-01

    Mutations in isocitrate dehydrogenase 1 (IDH1) have been found in the vast majority of low grade and progressive infiltrating gliomas and are characterized by the production of 2-hydroxyglutarate from α-ketoglutarate. Recent investigations of malignant gliomas have identified additional genetic and chromosomal abnormalities which cluster with IDH1 mutations into two distinct subgroups. The astrocytic subgroup was found to have frequent mutations in ATRX, TP53 and displays alternative lengthening of telomeres. The second subgroup with oligodendrocytic morphology has frequent mutations in CIC or FUBP1, and is linked to co-deletion of the 1p/19q arms. These mutations reflect the development of two distinct molecular pathways representing the majority of IDH1 mutant gliomas. Unfortunately, due to the scarcity of endogenously derived IDH1 mutant models, there is a lack of accurate models to study mechanism and develop new therapy. Here we report the generation of an endogenous IDH1 anaplastic astrocytoma in vivo model with concurrent mutations in TP53, CDKN2A and ATRX. The model has a similar phenotype and histopathology as the original patient tumor, expresses the IDH1 (R132H) mutant protein and exhibits an alternative lengthening of telomeres phenotype. The JHH-273 model is characteristic of anaplastic astrocytoma and represents a valuable tool for investigating the pathogenesis of this distinct molecular subset of gliomas and for preclinical testing of compounds targeting IDH1 mutations or alternative lengthening of telomeres. PMID:25471051

  4. Loss of wild-type ATRX expression in somatic cell hybrids segregates with activation of Alternative Lengthening of Telomeres.

    Directory of Open Access Journals (Sweden)

    Kylie Bower

    Full Text Available Alternative Lengthening of Telomeres (ALT is a non-telomerase mechanism of telomere lengthening that occurs in about 10% of cancers overall and is particularly common in astrocytic brain tumors and specific types of sarcomas. Somatic cell hybridization analyses have previously shown that normal telomerase-negative fibroblasts and telomerase-positive immortalized cell lines contain repressors of ALT activity, indicating that activation of ALT results from loss of one or more unidentified repressors. More recently, ATRX or DAXX was shown to be mutated both in tumors with telomere lengths suggestive of ALT activity and in ALT cell lines. Here, an ALT cell line was separately fused to each of four telomerase-positive cell lines, and four or five independent hybrid lines from each fusion were examined for expression of ATRX and DAXX and for telomere lengthening mechanism. The hybrid lines expressed either telomerase or ALT, with the other mechanism being repressed. DAXX was expressed normally in all parental cell lines and in all of the hybrids. ATRX was expressed normally in each of the four telomerase-positive parental cell lines and in every telomerase-positive hybrid line, and was abnormal in the ALT parental cells and in all but one of the ALT hybrids. This correlation between ALT activity and loss of ATRX expression is consistent with ATRX being a repressor of ALT.

  5. 不同冠延长术式处理上中切牙冠根折并桩核冠修复的三维有限元比较%Finite element analysis of the maxillary central incisor with traditional and modified crown lengthening surgery and post-core restoration in management of crown-root fracture

    Institute of Scientific and Technical Information of China (English)

    甄敏; 危伊萍; 胡文杰; 荣起国; 张豪

    2016-01-01

    Objective To construct three-dimensional finite element models with modified crown lengthening surgery and post-core restoration in management of various crown-root fracture types,to investigate the intensity and distribution of stressin models mentioned above,and to compare and analyze the indications of traditional and modified crown lengthening surgeries from the mechanic point of view.Methods Nine three-dimensional finite element models with modified crown lengthening surgery and post-core restoration were established and analyzed by micro-CT scanning technique,dental impression scanner,Mimics 10.0,Geomagic studio 9.0 and ANSYS 14.0 software.The von Mises stress of dentin,periodontal ligament,alveolar bone,post and core,as well as the periodontal ligament area and threshold limit value were calculated and compared with the findings of traditional crown lengthening models which had been published earlierby our research group.Results The yon Mises stress intensity of modified crown lengthening models were:dentin>post>core>alveolar bone>periodontal ligament.The maximum von Mises stress of dentin(44.37-80.58 MPa) distributed in lingual central shoulder.The periodontal ligament area of the modified crown lengthening surgery was reduced by 6% to 28%,under the same crown-root fracture conditions,the periodontal ligament area of modified crown lengthening models was larger than that of the traditional crown lengthening models.In modified crown lengthening surgery models,the yon Mises stress of periodontal ligament of B3L1m,B3L2m,B3L3m models exceeded their limit values,however,the yon Mises stress of periodontal ligament of the B2L2c,B2L3c,B3L1c,B3L2c,B3L3c models exceeded their limit values in traditional crown lengthening surgery models.Conclusions The modified crown lengthening surgery conserves more periodontal supporting tissues,which facilitates the long-term survival of teeth.The indication of modified crown lengthening surgery is wider than

  6. Bone marrow transplant

    Science.gov (United States)

    Transplant - bone marrow; Stem cell transplant; Hematopoietic stem cell transplant; Reduced intensity nonmyeloablative transplant; Mini transplant; Allogenic bone marrow transplant; Autologous bone marrow transplant; Umbilical ...

  7. Repeatability of corticospinal and spinal measures during lengthening and shortening contractions in the human tibialis anterior muscle.

    Directory of Open Access Journals (Sweden)

    Jamie Tallent

    Full Text Available UNLABELLED: Elements of the human central nervous system (CNS constantly oscillate. In addition, there are also methodological factors and changes in muscle mechanics during dynamic muscle contractions that threaten the stability and consistency of transcranial magnetic stimulation (TMS and perpherial nerve stimulation (PNS measures. PURPOSE: To determine the repeatability of TMS and PNS measures during lengthening and shortening muscle actions in the intact human tibialis anterior. METHODS: On three consecutive days, 20 males performed lengthening and shortening muscle actions at 15, 25, 50 and 80% of maximal voluntary contraction (MVC. The amplitude of the Motor Evoked Potentials (MEPs produced by TMS was measured at rest and during muscle contraction at 90° of ankle joint position. MEPs were normalised to Mmax determined with PNS. The corticospinal silent period was recorded at 80% MVC. Hoffman reflex (H-reflex at 10% isometric and 25% shortening and lengthening MVCs, and V-waves during MVCs were also evoked on each of the three days. RESULTS: With the exception of MEPs evoked at 80% shortening MVC, all TMS-derived measures showed good reliability (ICC = 0.81-0.94 from days 2 to 3. Confidence intervals (CI, 95% were lower between days 2 and 3 when compared to days 1 and 2. MEPs significantly increased at rest from days 1 to 2 (P = 0.016 and days 1 to 3 (P = 0.046. The H-reflex during dynamic muscle contraction was reliable across the three days (ICC = 0.76-0.84. V-waves (shortening, ICC = 0.77, lengthening ICC = 0.54 and the H-reflex at 10% isometric MVC (ICC = 0.66 was generally less reliable over the three days. CONCLUSION: Although it is well known that measures of the intact human CNS exhibit moment-to-moment fluctuations, careful experimental arrangements make it possible to obtain consistent and repeatable measurements of corticospinal and spinal excitability in the actively lengthening and shortening human

  8. Association of interleukin-6 signalling with the muscle stem cell response following muscle-lengthening contractions in humans.

    Directory of Open Access Journals (Sweden)

    Bryon R McKay

    Full Text Available BACKGROUND: The regulation of muscle stem cells in humans in response to muscle injury remains largely undefined. Recently, interleukin-6 (IL-6 has been implicated in muscle stem cell (satellite cell-mediated muscle hypertrophy in animals; however, the role of IL-6 in the satellite cell (SC response following muscle-lengthening contractions in humans has not been studied. METHODOLOGY/PRINCIPAL FINDINGS: Eight subjects (age 22+/-1 y; 79+/-8 kg performed 300 maximal unilateral lengthening contractions (3.14 rad.s(-1 of the knee extensors. Blood and muscle samples were collected before and at 4, 24, 72, and 120 hours post intervention. IL-6, IL-6 receptor, IL-6R(alpha, cyclin D1, suppressor of cytokine signling-3 (SOCS3 mRNA were measured using quantitative RT-PCR and serum IL-6 protein was measured using an ELISA kit. JAK2 and STAT3 phosphorylated and total protein was measured using western blotting techniques. Immunohistochemical analysis of muscle cross-sections was performed for the quantification of SCs (Pax7(+ cells as well as the expression of phosphorylated STAT3, IL-6, IL-6R(alpha, and PCNA across all time-points. The SC response, as defined by an amplification of Pax7(+ cells, was rapid, increasing by 24 h and peaking 72 h following the intervention. Muscle IL-6 mRNA increased following the intervention, which correlated strongly (R(2 = 0.89, p<0.002 with an increase in serum IL-6 concentration. SC IL-6R(alpha protein was expressed on the fiber, but was also localized to the SC, and IL-6(+ SC increased rapidly following muscle-lengthening contractions and returned to basal levels by 72 h post-intervention, demonstrating an acute temporal expression of IL-6 with SC. Phosphorylated STAT3 was evident in SCs 4 h after lengthening contraction, and the downstream genes, cyclin D1 and SOCS3 were significantly elevated 24 hours after the intervention. CONCLUSIONS/SIGNIFICANCE: The increased expression of STAT3 responsive genes and expression of

  9. Bone mineral content and bone metabolism in young adults with severe periodontitis

    DEFF Research Database (Denmark)

    Wowern von, N.; Westergaard, J.; Kollerup, G.

    2001-01-01

    Bone loss, bone markers, bone metabolism, bone mineral content, osteoporosis, severe periodontitis......Bone loss, bone markers, bone metabolism, bone mineral content, osteoporosis, severe periodontitis...

  10. Making Time for Nature: Visual Exposure to Natural Environments Lengthens Subjective Time Perception and Reduces Impulsivity.

    Directory of Open Access Journals (Sweden)

    Meredith S Berry

    opposed to built environments may be related to lengthened time perception.

  11. Spring blooms in the Baltic Sea have weakened but lengthened from 2000 to 2014

    Science.gov (United States)

    Groetsch, Philipp M. M.; Simis, Stefan G. H.; Eleveld, Marieke A.; Peters, Steef W. M.

    2016-09-01

    Phytoplankton spring bloom phenology was derived from a 15-year time series (2000-2014) of ship-of-opportunity chlorophyll a fluorescence observations collected in the Baltic Sea through the Alg@line network. Decadal trends were analysed against inter-annual variability in bloom timing and intensity, and environmental drivers (nutrient concentration, temperature, radiation level, wind speed).Spring blooms developed from the south to the north, with the first blooms peaking mid-March in the Bay of Mecklenburg and the latest bloom peaks occurring mid-April in the Gulf of Finland. Bloom duration was similar between sea areas (43 ± 2 day), except for shorter bloom duration in the Bay of Mecklenburg (36 ± 11 day). Variability in bloom timing increased towards the south. Bloom peak chlorophyll a concentrations were highest (and most variable) in the Gulf of Finland (20.2 ± 5.7 mg m-3) and the Bay of Mecklenburg (12.3 ± 5.2 mg m-3).Bloom peak chlorophyll a concentration showed a negative trend of -0.31 ± 0.10 mg m-3 yr-1. Trend-agnostic distribution-based (Weibull-type) bloom metrics showed a positive trend in bloom duration of 1.04 ± 0.20 day yr-1, which was not found with any of the threshold-based metrics. The Weibull bloom metric results were considered representative in the presence of bloom intensity trends.Bloom intensity was mainly determined by winter nutrient concentration, while bloom timing and duration co-varied with meteorological conditions. Longer blooms corresponded to higher water temperature, more intense solar radiation, and lower wind speed. It is concluded that nutrient reduction efforts led to decreasing bloom intensity, while changes in Baltic Sea environmental conditions associated with global change corresponded to a lengthening spring bloom period.

  12. [Lengthening temporalis myoplasty: A new approach to facial rehabilitation with the "mirror-effect" method].

    Science.gov (United States)

    Blanchin, T; Martin, F; Labbe, D

    2013-12-01

    Peripheral facial paralysis often reveals two conditions that are hard to control: labial occlusion and palpebral closure. Today, there are efforts to go beyond the sole use of muscle stimulation techniques, and attention is being given to cerebral plasticity stimulation? This implies using the facial nerves' efferent pathway as the afferent pathway in rehabilitation. This technique could further help limit the two recalcitrant problems, above. We matched two groups of patients who underwent surgery for peripheral facial paralysis by lengthening the temporalis myoplasty (LTM). LTM is one of the best ways to examine cerebral plasticity. The trigeminal nerve is a mixed nerve and is both motor and sensory. After a LTM, patients have to use the trigeminal nerve differently, as it now has a direct role in generating the smile. The LTM approach, using the efferent pathway, therefore, creates a challenge for the brain. The two groups followed separate therapies called "classical" and "mirror-effect". The "mirror-effect" method gave a more precise orientation of the patient's cerebral plasticity than did the classical rehabilitation. The method develops two axes: voluntary movements patients need to control their temporal smile; and spontaneous movements needed for facial expressions. Work on voluntary movements is done before a "digital mirror", using an identical doubled hemiface, providing the patient with a fake copy of his face and, thus, a 7 "mirror-effect". The spontaneous movements work is based on what we call the "Therapy of Motor Emotions". The method presented here is used to treat facial paralysis (Bell's Palsies type), whether requiring surgery or not. Importantly, the facial nerve, like the trigeminal nerve above, is also a mixed nerve and is stimulated through the efferent pathway in the same manner.

  13. Alternative mechanisms of telomere lengthening: Permissive mutations, DNA repair proteins and tumorigenic progression

    Energy Technology Data Exchange (ETDEWEB)

    Gocha, April Renee Sandy; Harris, Julia [Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University College of Medicine, Columbus, OH 43210 (United States); Groden, Joanna, E-mail: joanna.groden@osumc.edu [Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University College of Medicine, Columbus, OH 43210 (United States)

    2013-03-15

    Highlights: ► Neoplastic cells maintain telomeres by telomerase or ALT. ► Genetic mutations in p53, ATRX, DAXX or H3F3A may activate ALT. ► Many DNA repair proteins are involved in ALT. ► Tumor progression is favored by telomerase expression. - Abstract: Telomeres protect chromosome termini to maintain genomic stability and regulate cellular lifespan. Maintenance of telomere length is required for neoplastic cells after the acquisition of mutations that deregulate cell cycle control and increase cellular proliferation, and can occur through expression of the enzyme telomerase or in a telomerase-independent manner termed alternative lengthening of telomeres (ALT). The precise mechanisms that govern the activation of ALT or telomerase in tumor cells are unknown, although cellular origin may favor one or the other mechanisms. ALT pathways are incompletely understood to date; however, recent publications have increasingly broadened our understanding of how ALT is activated, how it proceeds, and how it influences tumor growth. Specific mutational events influence ALT activation, as mutations in genes that suppress recombination and/or alterations in the regulation of telomerase expression are associated with ALT. Once engaged, ALT uses DNA repair proteins to maintain telomeres in the absence of telomerase; experiments that manipulate the expression of specific proteins in cells using ALT are illuminating some of its mechanisms. Furthermore, ALT may influence tumor growth, as experimental and clinical data suggest that telomerase expression may favor tumor progression. This review summarizes recent findings in mammalian cells and models, as well as clinical data, that identify the genetic mutations permissive to ALT, the DNA repair proteins involved in ALT mechanisms and the importance of telomere maintenance mechanisms for tumor progression. A comprehensive understanding of the mechanisms that permit tumor cell immortalization will be important for identifying

  14. [Bone transplant].

    Science.gov (United States)

    San Julián, M; Valentí, A

    2006-01-01

    We describe the methodology of the Bone and Soft Tissue Bank, from extraction and storage until use. Since the year 1986, with the creation of the Bone Bank in the University Clinic of Navarra, more than 3,000 grafts have been used for very different types of surgery. Bone grafts can be classified into cortical and spongy; the former are principally used in surgery to save tumour patients, in large post-traumatic reconstructions and in replacement surgery where there are massive bone defects and a structural support is required. The spongy grafts are the most used due to their numerous indications; they are especially useful in filling cavities that require a significant quantity of graft when the autograft is insufficient, or as a complement. They are also of special help in treating fractures when there is bone loss and in the treatment of delays in consolidation and pseudoarthrosis in little vascularized and atrophic zones. They are also used in prosthetic surgery against the presence of cavity type defects. Allografts of soft tissues are specially recognised in multiple ligament injuries that require reconstructions. Nowadays, the most utilised are those employed in surgery of the anterior cruciate ligament although they can be used for filling any ligament or tendon defect. The principal difficulties of the cortical allografts are in the consolidation of the ends with the bone itself and in tumour surgery, given that these are patients immunodepressed by the treatment, the incidence of infection is increased with respect to spongy grafts and soft tissues, which is irrelevant. In short, the increasingly widespread use of allografts is an essential therapeutic weapon in orthopaedic surgery and traumatology. It must be used by expert hands.

  15. [Bone transplant].

    Science.gov (United States)

    San Julián, M; Valentí, A

    2006-01-01

    We describe the methodology of the Bone and Soft Tissue Bank, from extraction and storage until use. Since the year 1986, with the creation of the Bone Bank in the University Clinic of Navarra, more than 3,000 grafts have been used for very different types of surgery. Bone grafts can be classified into cortical and spongy; the former are principally used in surgery to save tumour patients, in large post-traumatic reconstructions and in replacement surgery where there are massive bone defects and a structural support is required. The spongy grafts are the most used due to their numerous indications; they are especially useful in filling cavities that require a significant quantity of graft when the autograft is insufficient, or as a complement. They are also of special help in treating fractures when there is bone loss and in the treatment of delays in consolidation and pseudoarthrosis in little vascularized and atrophic zones. They are also used in prosthetic surgery against the presence of cavity type defects. Allografts of soft tissues are specially recognised in multiple ligament injuries that require reconstructions. Nowadays, the most utilised are those employed in surgery of the anterior cruciate ligament although they can be used for filling any ligament or tendon defect. The principal difficulties of the cortical allografts are in the consolidation of the ends with the bone itself and in tumour surgery, given that these are patients immunodepressed by the treatment, the incidence of infection is increased with respect to spongy grafts and soft tissues, which is irrelevant. In short, the increasingly widespread use of allografts is an essential therapeutic weapon in orthopaedic surgery and traumatology. It must be used by expert hands. PMID:16998521

  16. What Is Bone?

    Science.gov (United States)

    ... by your browser. Home Bone Basics What Is Bone? Publication available in: PDF (57 KB) Related Resources ... Men, and Osteoporosis Osteoporosis Prevention For Your Information Bone Remodeling Throughout life, bone is constantly renewed through ...

  17. Calcium and bones

    Science.gov (United States)

    Bone strength and calcium ... calcium (as well as phosphorus) to make healthy bones. Bones are the main storage site of calcium in ... your body does not absorb enough calcium, your bones can get weak or will not grow properly. ...

  18. Facts about Broken Bones

    Science.gov (United States)

    ... White House Lunch Recipes The Facts About Broken Bones KidsHealth > For Kids > The Facts About Broken Bones ... through the skin . continue What Happens When a Bone Breaks? It hurts to break a bone! It's ...

  19. Bone biopsy (image)

    Science.gov (United States)

    A bone biopsy is performed by making a small incision into the skin. A biopsy needle retrieves a sample of bone and it ... examination. The most common reasons for bone lesion biopsy are to distinguish between benign and malignant bone ...

  20. Bone lesion biopsy

    Science.gov (United States)

    Bone biopsy; Biopsy - bone ... is sent to a lab for examination. Bone biopsy may also be done under general anesthesia to ... remove the bone can be done if the biopsy exam shows that there is an abnormal growth ...

  1. Bone graft revascularization strategies

    NARCIS (Netherlands)

    W.F. Willems

    2014-01-01

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

  2. Eco-region dependent lengthening of vegetation period over the past 30 years in Europe

    Science.gov (United States)

    Garonna, I.; De Jong, R.; De Wit, A.; Mücher, C. A.; Schmid, B.; Schaepman, M. E.

    2013-12-01

    Land Surface Phenology (LSP) is the most direct representation of intra-annual dynamics of vegetated land surfaces as observed from satellite observations. As such, LSP plays a key role in understanding the terrestrial carbon budget, as well as the response of terrestrial ecosystems to environmental change. Various studies have highlighted significant increases in vegetation activity over time (i.e. greening) over Europe in recent decades (e.g. Stöckli and Vidale, 2004), associated both with climatic changes and with large-scale human interventions including land-use change (de Jong et al., 2013). In this study, we characterize LSP changes in Europe's eco-regions for the last 30 years. We used the latest version of the 8-km Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index dataset (third generation, or NDVI-3g) to retrieve LSP metrics for Europe for the last three decades (1982-2011). Each year of NDVI data was processed using the Harmonic Analysis of Time Series (HANTS) algorithm, producing smooth NDVI annual profiles on a pixel-by-pixel basis. In order to derive LSP metrics for each year, namely Start, End and Length of Growing Season, we selected the Midpoint-pixel local threshold method, based on the White et al. (2009) inter-comparison. A landscape-based stratification, using the European Landscape Classification (LANMAP) (Mücher et al., 2010) allowed us to examine LSP characteristics and trends for the different European eco-regions. We demonstrate significant shifts in LSP metrics over the study period, with a general lengthening of the growing season in Europe of approximately 0.4 days year-1. LSP trends varied significantly between eco-regions, and we discuss potential reasons for these spatially diverse trends. de Jong, R., et al. (2013), Spatial relationship between climatologies and changes in global vegetation activity, Global Change Biology, 19(6), 1953-1964. Mücher, C. A., J. A. Klijn, D. M. Wascher, and

  3. Vangl2-regulated polarisation of second heart field-derived cells is required for outflow tract lengthening during cardiac development.

    Directory of Open Access Journals (Sweden)

    Simon A Ramsbottom

    2014-12-01

    Full Text Available Planar cell polarity (PCP is the mechanism by which cells orient themselves in the plane of an epithelium or during directed cell migration, and is regulated by a highly conserved signalling pathway. Mutations in the PCP gene Vangl2, as well as in other key components of the pathway, cause a spectrum of cardiac outflow tract defects. However, it is unclear why cells within the mesodermal heart tissue require PCP signalling. Using a new conditionally floxed allele we show that Vangl2 is required solely within the second heart field (SHF to direct normal outflow tract lengthening, a process that is required for septation and normal alignment of the aorta and pulmonary trunk with the ventricular chambers. Analysis of a range of markers of polarised epithelial tissues showed that in the normal heart, undifferentiated SHF cells move from the dorsal pericardial wall into the distal outflow tract where they acquire an epithelial phenotype, before moving proximally where they differentiate into cardiomyocytes. Thus there is a transition zone in the distal outflow tract where SHF cells become more polarised, turn off progenitor markers and start to differentiate to cardiomyocytes. Membrane-bound Vangl2 marks the proximal extent of this transition zone and in the absence of Vangl2, the SHF-derived cells are abnormally polarised and disorganised. The consequent thickening, rather than lengthening, of the outflow wall leads to a shortened outflow tract. Premature down regulation of the SHF-progenitor marker Isl1 in the mutants, and accompanied premature differentiation to cardiomyocytes, suggests that the organisation of the cells within the transition zone is important for maintaining the undifferentiated phenotype. Thus, Vangl2-regulated polarisation and subsequent acquisition of an epithelial phenotype is essential to lengthen the tubular outflow vessel, a process that is essential for on-going cardiac morphogenesis.

  4. Digital Smile Design concept delineates the final potential result of crown lengthening and porcelain veneers to correct a gummy smile.

    Science.gov (United States)

    Trushkowsky, Richard; Arias, David Montalvo; David, Steven

    2016-01-01

    Prior to initiating any treatment, it is necessary to visualize the desired outcomes. It then becomes possible to formulate the steps required to achieve this result. Digital Smile Design (DSD) utilizes patient input and information gathered through diagnostic procedures to create an esthetic treatment scheme. In the case presented here, the NYUCD Esthetic Evaluation Form, intraoral and extraoral photographs, mounted diagnostic casts, physical examination, and radiographs were the diagnostic modalities. The gathered information served as a starting point for a wax-up and intraoral mock-up. This case report demonstrates how the DSD served as a template for crown lengthening procedures and design of the final porcelain veneer restorations.

  5. Surgical exposure and crown lengthening for management of complicated fractures of maxillary anterior teeth. A case report.

    Science.gov (United States)

    Anand, Pradeep S; Ashok, Sukumaran; Nandakumar, K; Varghese, N O; Kamath, Kavitha P

    2013-11-01

    When a tooth fracture occurs, the fracture line can extend in a variety of directions, and the direction of the fracture line often dictates the treatment plan. In cases where fracture lines extend apical to the gingival margin, exposure of fractured margins becomes necessary. And management of such tooth fractures often requires an interdisciplinary approach involving endodontic, periodontic and restorative procedures. This article describes a case in which severely traumatized maxillary anterior teeth were managed by a combined approach involving surgical exposure and crown lengthening, endodontic and restorative procedures.

  6. Experimental evaluation of the oxygen transfer in bubble aeration systems. Full scale experiences in lengthened activated sludge reactors

    International Nuclear Information System (INIS)

    The results of some full-scale oxygen transfer measurements conduced at the lengthened activate sludge tanks of two WWTPs of Trentino Region, are presented and discussed. As far at the tests in clean water are concerned, the non-liner regression method seems non accurate; important conclusion on the correlation between oxygen transfer process and typical parameters (i.e., fine-bubble diffusers, specific air flux) are derived. As far as the test in the wastewater is concerned, an increase of α-value from the inlet to the end of aeration tanks has been observed in the 'Andalo' WWTP

  7. Break-induced replication requires DNA damage-induced phosphorylation of Pif1 and leads to telomere lengthening.

    Directory of Open Access Journals (Sweden)

    Yulia Vasianovich

    2014-10-01

    Full Text Available Broken replication forks result in DNA breaks that are normally repaired via homologous recombination or break induced replication (BIR. Mild insufficiency in the replicative ligase Cdc9 in budding yeast Saccharomyces cerevisiae resulted in a population of cells with persistent DNA damage, most likely due to broken replication forks, constitutive activation of the DNA damage checkpoint and longer telomeres. This telomere lengthening required functional telomerase, the core DNA damage signaling cascade Mec1-Rad9-Rad53, and the components of the BIR repair pathway - Rad51, Rad52, Pol32, and Pif1. The Mec1-Rad53 induced phosphorylation of Pif1, previously found necessary for inhibition of telomerase at double strand breaks, was also important for the role of Pif1 in BIR and telomere elongation in cdc9-1 cells. Two other mutants with impaired DNA replication, cdc44-5 and rrm3Δ, were similar to cdc9-1: their long telomere phenotype was dependent on the Pif1 phosphorylation locus. We propose a model whereby the passage of BIR forks through telomeres promotes telomerase activity and leads to telomere lengthening.

  8. Osteoclasts prefer aged bone

    DEFF Research Database (Denmark)

    Henriksen, K; Leeming, Diana Julie; Byrjalsen, I;

    2007-01-01

    We investigated whether the age of the bones endogenously exerts control over the bone resorption ability of the osteoclasts, and found that osteoclasts preferentially develop and resorb bone on aged bone. These findings indicate that the bone matrix itself plays a role in targeted remodeling...

  9. Oestradiol and testosterone binding sites in mice tibiae and their relationship with bone growth.

    Science.gov (United States)

    Lopez, A; Ventanas, J; Burgos, J

    1986-11-01

    High affinity oestradiol and testosterone binding sites were found in tibiae cytosol from entire male and female of different ages. Scatchard assay allowed to estimate a Kd of 2.7 X 10(-9) M for oestradiol binding sites indicating that the 3H-oestradiol binding was of high affinity. Oestradiol and testosterone binding sites abundance in mice tibiae are subject to change with age. It is not easy to establish a direct correlation between these changes and the values reported here on bone growth in weight and length, however seems possible to point a negative relationship between bone lengthening and oestradiol binding site levels in female, as well a positive relationship with testosterone in both sexes. The presence of oestradiol and testosterone binding sites in epiphyses and not in the diaphyses reinforces the hypothesis that both are playing some role in bone growth.

  10. In vivo open-bore MRI reveals region- and sub-arc-specific lengthening of the unloaded human posterior cruciate ligament.

    Directory of Open Access Journals (Sweden)

    Alison J King

    Full Text Available Open-bore MRI scanners allow joint soft tissue to be imaged over a large, uninterrupted range of flexion. Using an open-bore scanner, 3D para-sagittal images of the posterior cruciate ligament (PCL were collected from seven healthy subjects in unloaded, recumbent knee extension and flexion. PCL length was measured from one 2D MRI slice partition per flexion angle, per subject. The anterior surface of the PCL lengthened significantly between extension and flexion (p<0.001. Conversely, the posterior surface did not. Changes were not due to the PCL moving relative to the 2D slice partition; measurements made from 3D reconstructions, which compensated for PCL movement, did not differ significantly from measurements made from 2D slice partitions. In a second experiment, videos of knee flexion were made by imaging two subjects at several flexion angles. Videos allowed soft tissue tracking; examples are included. In a third experiment, unloaded knees of seven healthy, recumbent subjects were imaged at extension and at 40°, 70°, 90°, 100°, 110° and 120° flexion. The distance between PCL attachments increased between extension and 100°, and then decreased (p<0.001. The anterior surface of the PCL lengthened over the flexion angles measured (p<0.01. The posterior surface of the PCL lengthened between extension and 40° and then shortened (p<0.001. Both attachment separation and anterior surface length increased dramatically between extension and 40°, but varied less afterwards. Results indicate that PCL dynamics differ between terminal extension and active function sub-arcs. Also, attachment separation cannot predict the lengthening of all parts of the PCL, nor can lengthening of one part of the PCL predict the lengthening of another part. A potential connection between lengthening and loading is discussed. We conclude that low-field MRI can assess ligament lengthening during flexion, and that the dynamics of the PCL for any given region and sub

  11. Bone marrow aspiration

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003658.htm Bone marrow aspiration To use the sharing features on this page, please enable JavaScript. Bone marrow is the soft tissue inside bones that helps ...

  12. Bone marrow biopsy

    Science.gov (United States)

    Biopsy - bone marrow ... A bone marrow biopsy may be done in the health care provider's office or in a hospital. The sample may be taken from the pelvic or breast bone. Sometimes, other areas are used. Marrow is removed ...

  13. The Effect of Altering the Mechanical Loading Environment on the Expression of Bone Regenerating Molecules in Cases of Distraction Osteogenesis

    Directory of Open Access Journals (Sweden)

    Mohammad M Alzahrani

    2014-12-01

    Full Text Available Distraction osteogenesis (DO is a surgical technique where gradual and controlled separation of two bony fragments following an osteotomy leads to the induction of new bone formation in the distracted gap. DO is used for limb lengthening, correction of bony deformities and the replacement of bone loss secondary to infection, trauma and tumors. Although DO gives satisfactory results in most cases, one major drawback of this technique is the prolonged period of time the external fixator has to be kept on until the newly formed bone consolidates thus leading to numerous complications. Numerous attempts at accelerating bone formation during DO have been reported. One specific approach is manipulation of the mechanical environment during DO by applying changes in the standard protocol of distraction. Attempts at changing this mechanical environment led to mixed results. Increasing the rate or applying acute distraction, led to poor bone formation in the distracted zone. On the other hand, the addition of compressive forces (such as weight bearing, alternating distraction with compression or by over-lengthening and then shortening has been reported to increase bone formation. It still remains unclear why these alterations may lead to changes in bone formation. While the cellular and molecular changes occurring during the standard DO protocol, specifically increased expression of transforming growth factor-β1, platelet derived growth factor, insulin-like growth factor, basic fibroblast growth factor, vascular endothelial growth factor, and bone morphogenic proteins have been extensively investigated, the literature is sparse on the changes occurring when this protocol is altered. It is the purpose of this article to review the pertinent literature on the changes in the expression of various proteins and molecules as a result of changes in the mechanical loading technique in DO and try to define potential future research directions.

  14. Anorexia Nervosa and Bone

    OpenAIRE

    Misra, Madhusmita; Klibanski, Anne

    2014-01-01

    Anorexia nervosa (AN) is a condition of severe low weight that is associated with low bone mass, impaired bone structure and reduced bone strength, all of which contribute to increased fracture risk., Adolescents with AN have decreased rates of bone accrual compared with normal-weight controls, raising addition concerns of suboptimal peak bone mass and future bone health in this age group. Changes in lean mass and compartmental fat depots, hormonal alterations secondary to nutritional factors...

  15. Combined crown lengthening surgery with restorative therapy for inducing papilla growth: a case report%牙冠延长术结合修复治疗诱导上前牙龈乳头生长1例

    Institute of Scientific and Technical Information of China (English)

    乐迪; 胡文杰; 张豪

    2013-01-01

    A young lady with unsatisfied restorations of upper anterior teeth and swollen gum wanted to improve aesthetics. Oral examination showed that 12-22 were provisional crowns with normal occlusion, poorly gingival contour and gummy smile. The gingiva was red, light swollen and bleeding on probing. X-ray showed the roots of 11, 21 were short and the alveolar bone absorbed. After the periodontal initial treatment, an ideal location of gingival margin was determined. Then, an esthetic periodontal surgery was performed to recover the biology width and the gingival margin was fitted with the anterior teeth. The temporary restorations were made twice to guide the gingiva growth by changing the shape of the restorations and moving up the contact points of the restorations. The ceramic crowns were completed 3 months after the operation. The gummy smile disappeared and the gingival margin was filled well with the upper anterior ceramic crowns. The 14-month follow-up presented a satisfied effect. Crown lengthening surgery combined restorative therapy could lead papilla to grow well. This process is beneficial for the future treatment plan and clinical esthetic evaluation.

  16. Bone marrow transplant - discharge

    Science.gov (United States)

    Transplant - bone marrow - discharge; Stem cell transplant - discharge; Hematopoietic stem cell transplant - discharge; Reduced intensity; Non-myeloablative transplant - discharge; Mini transplant - discharge; Allogenic bone marrow transplant - discharge; ...

  17. Lack of telomerase RNA gene hTERC expression in alternative lengthening of telomeres cells is associated with methylation of the hTERC promoter

    NARCIS (Netherlands)

    Hoare, SF; Bryce, LA; Wisman, GBA; Burns, S; Going, JJ; van der Zee, AGJ; Keith, WN

    2001-01-01

    The immortal phenotype of most human cancers is attributable to telomerase expression. However, a number of immortal cell lines and tumors achieve telomere maintenance in the absence of telomerase via alternative mechanisms known as ALT (alternative lengthening of telomeres). Here we show that the p

  18. Growth rate after limb deformity correction by the Ilizarov method with or without knee joint distraction Lengthening in 30 children followed for at least 2 years

    NARCIS (Netherlands)

    Oostenbroek, Hubert J.; Brand, Ronald; van Roermund, Peter M.

    2009-01-01

    Background and purpose Growth inhibition and stimulation have both been reported after juvenile limb lengthening. Distraction of a joint usually suspends and unloads the growth plate and may stimulate growth. We investigated the influence of knee joint distraction on the speed of growth after limb l

  19. Alongamento simultâneo do rádio e ulna em cães pelo método de Ilizarov Simultaneous lengthening of radius and ulna in dogs with the Ilizarov method

    Directory of Open Access Journals (Sweden)

    S.C. Rahal

    2002-04-01

    Full Text Available Com o objetivo de avaliar a funcionalidade de uma montagem do aparelho de Ilizarov para o alongamento simultâneo do rádio e da ulna, foram utilizados 15 cães, sem raça definida, adultos, com peso entre 17 e 27kg. Aplicado um fixador composto de dois anéis e quatro hastes telescópicas, realizaram-se osteotomia subperiosteal diafisária distal do rádio e ulna e distração óssea, iniciada no sexto dia de pós-operatório. Os animais foram divididos em cinco grupos formados cada um por três cães, submetidos às seguintes condutas: A- oito dias de alongamento, B- 15 dias de alongamento, C- 22 dias de alongamento, D- 28 dias de alongamento e oito dias de fase neutra com o fixador e E- 28 dias de alongamento, 60 dias de fase neutra com fixador e 45 dias sem fixador. No período de distração os animais desenvolveram gradual e progressiva contratura em flexão da articulação antebraquiocárpica, que persistiu no grupo E após a remoção do fixador. Conclui-se que no alongamento do antebraço há tendência para o desenvolvimento de contratura, recomendando-se medidas preventivas e fisioterapia.The aim of this study was to evaluate configuration of the Ilizarov fixator for simultaneous lengthening of radius and ulna. Fifteen adult crossbreed dogs weighting from 17 to 27kg were used. A two-ring and four telescopic rod configuration was placed in radius and ulna. Subperiosteal osteotomies of the radius and the distal diaphysis of the ulna were performed and bone distraction started at day six after surgery. These dogs were divided in five groups containing three animals each, which were submitted to the following procedures: A- eight days of distraction, B- 15 days of distraction, C- 22 days of distraction, D- 28 days of distraction and eight days of neutral fixation, and E- 28 days of distraction, 60 days of neutral fixation, and 45 days without the apparatus. During the distraction period the animals developed a gradual and progressive

  20. Bone grafting: An overview

    Directory of Open Access Journals (Sweden)

    D. O. Joshi

    2010-08-01

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

  1. Bone scan in rheumatology

    International Nuclear Information System (INIS)

    In this chapter a revision is made concerning different uses of bone scan in rheumatic diseases. These include reflex sympathetic dystrophy, osteomyelitis, spondyloarthropaties, metabolic bone diseases, avascular bone necrosis and bone injuries due to sports. There is as well some comments concerning pediatric pathology and orthopedics. (authors). 19 refs., 9 figs

  2. Bone Marrow Transplantation

    Science.gov (United States)

    Bone marrow is the spongy tissue inside some of your bones, such as your hip and thigh bones. It contains immature cells, called stem cells. The ... platelets, which help the blood to clot. A bone marrow transplant is a procedure that replaces a ...

  3. Bone grafts in dentistry

    Directory of Open Access Journals (Sweden)

    Prasanna Kumar

    2013-01-01

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

  4. Clinical effects of modified surgical crown lengthening%改良牙冠延长术临床疗效的观察

    Institute of Scientific and Technical Information of China (English)

    章彦彦; 陈才展; 邓燕; 杨旭; 黄继洪; 高丽萍

    2013-01-01

    AIM:To observe the clinical effects of modified crown lengthening surgery.METHODS:Modified crown lengthening was performed on 31 teeth with crown defects involved more than 3 mm subgingivally.Plaque index (PLI),bleeding index (BI),probing depth (PD) and tooth mobility (TM) were measured before and 1,3,9 and 15 months after operation at follow-up.RESULTS:PLI,BI,PD and TM were significantly decreased at 1,3,9and 15 months after modified crown lengthening (P < 0.05).Gingival health and gingival margin coordination were improved,prosthetic replacements were stable in all patienrs.CONCLUSION:Modified surgical crown lengthening is an effective surgical method for conventional crown lengthening.%目的:观察改良牙冠延长术的临床疗效.方法:对31例患者的31个牙体缺损延伸至龈下3.0 mm以上患牙行改良牙冠延长术,术后1、3、9、15个月随访,比较患牙术前后的菌斑指数(PLI)、出血指数(BI)、牙周探诊深度(PD)和松动度(TM).结果:31个患牙术后1,3,9,15个月的PD、BI、PLI、TM较术前改善明显(均为P<0.05);术后无松动、牙龈健康、龈缘协调;修复体稳定;患者自诉功能良好,疗效满意.结论:改良牙冠延长术可作为常规牙冠延长术不足的一种弥补.

  5. 改良型牙冠延长术应用于病损达龈下的后牙临床评价%Clinical Evaluation of A Modified Technioue for Surgical Crown Lengthening to the Molars Destroyed Below the Gingiva

    Institute of Scientific and Technical Information of China (English)

    文萍; 安志国; 吴敏; 刘寿桃; 李蕙君

    2011-01-01

    目的 评价改良式牙冠延长术应用于治疗龋坏或劈裂达龈下的后牙的临床效果.方法 7颗龋损或劈裂达龈下的后牙,采用仅降低病损部位牙槽骨高度的方法来恢复丧失的生物学宽度,3个月后全冠修复,定期随访检查牙齿松动度、菌斑指数、牙龈指数和探诊深度.结果 7例患者追踪观察15 ~24个月,平均21.7个月,患牙牙龈健康、美观、稳定.结论 作为传统术式的一种改良,后牙改良式牙冠延长术在满足患区修复学要求的同时,又减少了其他部位由于主动性去骨而造成的不良后果.%Objective To evaluate the clinical effect of a modified technique for surgical crown lengthening implemented the molars destroyed below the gingiva. Methods The alternative to the traditional method involves lowering the height of alveolar bone in the destroyed region to rebuild the biological width. All of these 7 molars,with certain region destroyed below the gingiva by caries or fracture were considered as not suitable for the traditional prosthetics methods. They were treated by this modified method of surgical crown lengthening. Restoration was accomplished on these teeth three month later. Periodontal index such as tooth mobility,plaque index,probing depth and bleeding index were recor-ded and followed up for more than 15 months. Results The mean follow-up period was 21.7 months (ranged from 15 to 24 months). Result of surgery and restoration of these 7 teeth was satisfactory. The gingival tissue remained healthy and esthetic with good function. Conclusion As an alternative to the traditional method,this modified surgical crown lengthening can not only meet the demand of prosthetics in the destroyed region,but also reduce the negative consequences for excessive lowering the bone height in the other region.

  6. Bone Health and Osteoporosis.

    Science.gov (United States)

    Lupsa, Beatrice C; Insogna, Karl

    2015-09-01

    Osteoporosis is characterized by low bone mass and microarchitectural deterioration of bone tissue leading to decreased bone strength and an increased risk of low-energy fractures. Central dual-energy X-ray absorptiometry measurements are the gold standard for determining bone mineral density. Bone loss is an inevitable consequence of the decrease in estrogen levels during and following menopause, but additional risk factors for bone loss can also contribute to osteoporosis in older women. A well-balanced diet, exercise, and smoking cessation are key to maintaining bone health as women age. Pharmacologic agents should be recommended in patients at high risk for fracture.

  7. BONE IN OSTEOPETROSIS

    Directory of Open Access Journals (Sweden)

    Ramkumar

    2014-04-01

    Full Text Available Osteopetrosis, a generalized developmental bone disease due to genetic disturbances, characterized by failure of bone re sorption and continuous bone formation making the bone hard, dense and brittle. Bones of intramembranous ossification and enchondrial ossification are affected genetically and symmetrically. During the process of disease the excess bone formation obliterates the cranial foramina and presses the optic, auditory and facial nerves resulting in defective vision, impaired hearing and facial paralysis. The bone formation in osteopetrosis affects bone marrow function leading to severe anemia and deficient of blood cells. The bone devoid of blood supply due to compression of blood vessels by excess formation of bone are prone to osteomyelitic changes with suppuration and pathological fracture if exposed to infection. Though the condition is chronic progressive, it produces changes leading to fatal condition, it should be studied thoroughly by everyone and hence this article presents a classical case of osteopetrosis with detailed description and discussion for the benefit of readers

  8. The analysis of the application of crown lengthening surgery in the dental restoration of traumatic anterior teeth%牙冠延长术在外伤前牙修复中的临床应用

    Institute of Scientific and Technical Information of China (English)

    刘赟; 高婵; 吴佩; 汪春仙; 熊贵忠; 刘心

    2014-01-01

    Objective:To investigate the clinical efficacy of crown lengthening of shortening or subgingival teeth on restoration of the traumatic anterior. Method:The front 50 teeth choice of trauma cases after loosening degree less than or e-qual to the first degree,subgingival crown fracture was above or equal 3 mm,after complete periodontal therapy,using method of flap combined with excision of bone turnover and root crown repositioned flap operation for lengthening surgery, routine repair in patients according to their oral cavity after 4~6 weeks operation. Result:All traumatic anterior teeth after operation may obtain enough clinical crown length,which resulting ferrule effect effective. Follow-up with traumatic anterior teeth after operation,gingival color is normal,its height is adjust with neighbor teeth,and all coordination is meet with crown edge sealing. Patient is satisfy with the function and elegant appearance of the traumatic anterior teeth after operation. Con-clusion:Crown lengthening is great significance of successful repair surgery of traumatic anterior teeth. In the process of op-eration and repair,we need to pay further attention to detail and time selection of repair surgery.%目的:探讨牙冠延长术在外伤前牙牙冠过短或缺损至龈下的患牙进行修复的临床疗效。方法:选择外伤后松动度≤Ⅰ度,牙冠折断至龈下≥3 mm的前牙52颗,对患牙完成根管治疗及牙周基础治疗后,采用翻瓣联合骨切除的方法及根向复位瓣手术行牙冠延长术,术后4~6周根据患者的口腔情况进行常规桩核冠修复。结果:所有患牙术后获得足够的临床冠长度,残根断端产生有效的箍效应。术后对患牙进行跟踪随访,患牙龈缘色泽正常、高度与邻牙相协调、全冠边缘密合。患者对患牙的功能、美观满意。结论:牙冠延长术对于外伤前牙的成功修复有重要意义,治疗过程中应注重手术的细节及修复时机的选择。

  9. Bone cysts: unicameral and aneurysmal bone cyst.

    Science.gov (United States)

    Mascard, E; Gomez-Brouchet, A; Lambot, K

    2015-02-01

    Simple and aneurysmal bone cysts are benign lytic bone lesions, usually encountered in children and adolescents. Simple bone cyst is a cystic, fluid-filled lesion, which may be unicameral (UBC) or partially separated. UBC can involve all bones, but usually the long bone metaphysis and otherwise primarily the proximal humerus and proximal femur. The classic aneurysmal bone cyst (ABC) is an expansive and hemorrhagic tumor, usually showing characteristic translocation. About 30% of ABCs are secondary, without translocation; they occur in reaction to another, usually benign, bone lesion. ABCs are metaphyseal, excentric, bulging, fluid-filled and multicameral, and may develop in all bones of the skeleton. On MRI, the fluid level is evocative. It is mandatory to distinguish ABC from UBC, as prognosis and treatment are different. UBCs resolve spontaneously between adolescence and adulthood; the main concern is the risk of pathologic fracture. Treatment in non-threatening forms consists in intracystic injection of methylprednisolone. When there is a risk of fracture, especially of the femoral neck, surgery with curettage, filling with bone substitute or graft and osteosynthesis may be required. ABCs are potentially more aggressive, with a risk of bone destruction. Diagnosis must systematically be confirmed by biopsy, identifying soft-tissue parts, as telangiectatic sarcoma can mimic ABC. Intra-lesional sclerotherapy with alcohol is an effective treatment. In spinal ABC and in aggressive lesions with a risk of fracture, surgical treatment should be preferred, possibly after preoperative embolization. The risk of malignant transformation is very low, except in case of radiation therapy.

  10. Biomechanical properties of regenerated bone by mandibular distraction osteogenesis

    Institute of Scientific and Technical Information of China (English)

    李继华; 胡静; 王大章; 唐正龙; 高占巍

    2002-01-01

    Objective: To study the biomechanical properties of the new bone generated by mandibular distractionosteogenesis (DO).Methods: A total of 11 healthy adult goats wererandomly divided into 2 groups, the experimental group (n=9) and the control group (n = 2). For the goats in theexperimental group, the bilateral mandibles were graduallylengthened for 10 mm with distraction appliances. Threegoats were sacrificed respectively at 2, 4 and 8 weeks aftercompletion of distraction. Compressive, three-pointbending and shearing tests were conducted on the standardregenerated bone samples and the whole unilateralmandibular specimens. For the goats in the control group,no operation was made and the whole unilateral mandiblewas taken as the test specimen.Results: The compressive strength and bendingstiffness of the new bone reached the normal level at 4 and 8weeks after completion of distraction, respectively. But theshearing strength remained significantly weaker than that of the controls at 8 weeks after distraction.Conclusions: The distraction appliance can beremoved and the lengthened mandible should be exposed toadaptive functional exercise at 8 weeks after completion ofdistraction.

  11. Impact of lengthening open water season on food security in Alaska coastal communities: Global impacts may outweigh local "frontline" effects

    Science.gov (United States)

    Rolph, R.; Mahoney, A. R.

    2015-12-01

    Using ice concentration data from the Alaska Sea Ice Atlas from 1953-2013 for selected communities in Alaska, we find a consistent trend toward later freeze up and earlier breakup, leading a lengthened open water period. Such changes are often considered to bring a variety of "frontline" local impacts to Arctic coastal communities such as increased rates of coastal erosion. However, direct consequences of these changes to local food security (e.g. through impacts on subsistence activities and marine transport of goods) may be outweighed at least in the short term by the effects of large scale Arctic sea ice change coupled with global oil markets. For example, a later freeze-up might delay local hunters' transition from boats to snow-machines, but whether this trend will affect hunting success, especially in the next few years, is uncertain. Likewise, the magnitude of change in open water season length is unlikely to be sufficient to increase the frequency with which communities are served by barges. However, an expanding open water season throughout the Arctic has implications for the global economy, which can have indirect effects on local communities. In the Chukchi and Beaufort Seas, where rapid sea ice change has been accompanied by increased interest in oil and gas development, the U.S. Bureau of Ocean Energy Management currently requires drilling operations to cease 38 days prior to freeze up. Taking this into account, the lengthening open water season has effectively extended the drilling season for oil companies by 184% since the 1950s. If oil development goes ahead, local communities will likely experience a range of indirect impacts on food security due to increased vessel traffic and demand on infrastructure coupled with changes in local economies and employment opportunities. Increased likelihood of an oil spill in coastal waters also poses a significant threat to local food security. Thus, while Arctic coastal communities are already experiencing

  12. How Is Bone Cancer Diagnosed?

    Science.gov (United States)

    ... with bone cancer. Accurate diagnosis of a bone tumor often depends on combining information about its location (what bone is affected and even which part of the bone is involved), appearance on x-rays, and appearance under a microscope. ...

  13. Neonatal Mandibular Distraction Osteogenesis Reduces Cleft Palate Width and Lengthens Soft Palate, Influencing Palatoplasty in Patients With Pierre Robin Sequence.

    Science.gov (United States)

    Collares, Marcus V M; Duarte, Daniele W; Sobral, Davi S; Portinho, Ciro P; Faller, Gustavo J; Fraga, Mariana M

    2016-07-01

    The aim of this study was to evaluate the influence of neonatal mandibular distraction osteogenesis (MDO) on cleft dimensions and on early palatoplasty outcomes in patients with Pierre Robin Sequence (PRS). In a prospective cohort study that enrolled 24 nonsyndromic patients with PRS, 12 submitted to the MDO group and 12 patients not treated (non-MDO group), the authors compared patients for cleft palate dimensions through 7 morphometric measurements at the moment of palatoplasty and for early palatoplasty outcomes. At palatoplasty, the MDO group presented a significant shorter distance between the posterior nasal spines (PNS-PNS, P < 0.001) and between uvular bases (UB-UB, P < 0.001), representing a reduction in cleft palate width. They also had significant soft palate lengthening represented by a larger distance between UB and retromolar space (UB-RM, P < 0.001) and UB and PNS (UB-PNS, P = 0.014). Their UB moved away from the posterior wall of the nasopharynx (UB-NPH, P < 0.001). The MDO group had a length of operative time significantly shorter (P < 0.001) and no early palatoplasty complications compared with the non-MDO group. In conclusion, MDO acted as an orthopedic procedure that reduced cleft palate width and elongated the soft palate in patients with PRS. These modifications enabled a reduction of around 11% in the length of operative time of palatoplasty (P < 0.001).

  14. Loss of ATRX, genome instability, and an altered DNA damage response are hallmarks of the alternative lengthening of telomeres pathway.

    Directory of Open Access Journals (Sweden)

    Courtney A Lovejoy

    Full Text Available The Alternative Lengthening of Telomeres (ALT pathway is a telomerase-independent pathway for telomere maintenance that is active in a significant subset of human cancers and in vitro immortalized cell lines. ALT is thought to involve templated extension of telomeres through homologous recombination, but the genetic or epigenetic changes that unleash ALT are not known. Recently, mutations in the ATRX/DAXX chromatin remodeling complex and histone H3.3 were found to correlate with features of ALT in pancreatic neuroendocrine cancers, pediatric glioblastomas, and other tumors of the central nervous system, suggesting that these mutations might contribute to the activation of the ALT pathway in these cancers. We have taken a comprehensive approach to deciphering ALT by applying genomic, molecular biological, and cell biological approaches to a panel of 22 ALT cell lines, including cell lines derived in vitro. Here we show that loss of ATRX protein and mutations in the ATRX gene are hallmarks of ALT-immortalized cell lines. In addition, ALT is associated with extensive genome rearrangements, marked micronucleation, defects in the G2/M checkpoint, and altered double-strand break (DSB repair. These attributes will facilitate the diagnosis and treatment of ALT positive human cancers.

  15. PML induces compaction, TRF2 depletion and DNA damage signaling at telomeres and promotes their alternative lengthening.

    Science.gov (United States)

    Osterwald, Sarah; Deeg, Katharina I; Chung, Inn; Parisotto, Daniel; Wörz, Stefan; Rohr, Karl; Erfle, Holger; Rippe, Karsten

    2015-05-15

    The alternative lengthening of telomeres (ALT) mechanism allows cancer cells to escape senescence and apoptosis in the absence of active telomerase. A characteristic feature of this pathway is the assembly of ALT-associated promyelocytic leukemia (PML) nuclear bodies (APBs) at telomeres. Here, we dissected the role of APBs in a human ALT cell line by performing an RNA interference screen using an automated 3D fluorescence microscopy platform and advanced 3D image analysis. We identified 29 proteins that affected APB formation, which included proteins involved in telomere and chromatin organization, protein sumoylation and DNA repair. By integrating and extending these findings, we found that APB formation induced clustering of telomere repeats, telomere compaction and concomitant depletion of the shelterin protein TRF2 (also known as TERF2). These APB-dependent changes correlated with the induction of a DNA damage response at telomeres in APBs as evident by a strong enrichment of the phosphorylated form of the ataxia telangiectasia mutated (ATM) kinase. Accordingly, we propose that APBs promote telomere maintenance by inducing a DNA damage response in ALT-positive tumor cells through changing the telomeric chromatin state to trigger ATM phosphorylation. PMID:25908860

  16. Use of modified lip repositioning technique associated with esthetic crown lengthening for treatment of excessive gingival display: A case report of multiple etiologies

    Directory of Open Access Journals (Sweden)

    Matheus Bortoluzzi Mantovani

    2016-01-01

    Full Text Available Excessive gingival display during smile can result in compromised esthetics. This study aims to report a case of excessive gingival display with multiple etiologies treated by means of modified lip repositioning technique associated with esthetic crown lengthening. A 23-year-old female patient, with 5-mm gingival display during smile caused by altered passive eruption and hypermobility of the upper lip, underwent the modified lip repositioning technique associated with gingivectomy followed by flap elevation and ostectomy/osteoplasty. Seven months after the second procedure, the patient had her esthetic complaint solved appearing stable in the observation period. The modified lip repositioning technique is an effective procedure employed to reduce gingival display and when associated with esthetic clinical crown lengthening, can appropriately treat cases of gummy smile.

  17. Use of modified lip repositioning technique associated with esthetic crown lengthening for treatment of excessive gingival display: A case report of multiple etiologies.

    Science.gov (United States)

    Mantovani, Matheus Bortoluzzi; Souza, Eduardo Clemente; Marson, Fabiano Carlos; Corrêa, Giovani Oliveira; Progiante, Patrícia Saram; Silva, Cléverson Oliveira

    2016-01-01

    Excessive gingival display during smile can result in compromised esthetics. This study aims to report a case of excessive gingival display with multiple etiologies treated by means of modified lip repositioning technique associated with esthetic crown lengthening. A 23-year-old female patient, with 5-mm gingival display during smile caused by altered passive eruption and hypermobility of the upper lip, underwent the modified lip repositioning technique associated with gingivectomy followed by flap elevation and ostectomy/osteoplasty. Seven months after the second procedure, the patient had her esthetic complaint solved appearing stable in the observation period. The modified lip repositioning technique is an effective procedure employed to reduce gingival display and when associated with esthetic clinical crown lengthening, can appropriately treat cases of gummy smile.

  18. Use of modified lip repositioning technique associated with esthetic crown lengthening for treatment of excessive gingival display: A case report of multiple etiologies.

    Science.gov (United States)

    Mantovani, Matheus Bortoluzzi; Souza, Eduardo Clemente; Marson, Fabiano Carlos; Corrêa, Giovani Oliveira; Progiante, Patrícia Saram; Silva, Cléverson Oliveira

    2016-01-01

    Excessive gingival display during smile can result in compromised esthetics. This study aims to report a case of excessive gingival display with multiple etiologies treated by means of modified lip repositioning technique associated with esthetic crown lengthening. A 23-year-old female patient, with 5-mm gingival display during smile caused by altered passive eruption and hypermobility of the upper lip, underwent the modified lip repositioning technique associated with gingivectomy followed by flap elevation and ostectomy/osteoplasty. Seven months after the second procedure, the patient had her esthetic complaint solved appearing stable in the observation period. The modified lip repositioning technique is an effective procedure employed to reduce gingival display and when associated with esthetic clinical crown lengthening, can appropriately treat cases of gummy smile. PMID:27041845

  19. Gait Analysis before and after Gastrocnemius Fascia Lengthening for Spastic Equinus Foot Deformity in a 10-Year-Old Diplegic Child

    Directory of Open Access Journals (Sweden)

    Manuela Galli

    2010-01-01

    Full Text Available Purpose. This case study quantified kinematic and kinetic effects of gastrocnemius lengthening on gait in a Cerebral Palsy child with equinus foot. Methods. A 10-year-old diplegic child with Cerebral Palsy was evaluated with Gait Analysis (GA before and after gastrocnemius fascia lengthening, investigating the lower limb joints kinematics and kinetics. Results. Kinematics improved at the level of distal joints, which are directly associated to gastrocnemius, and also at the proximal joint (like hip; improvements were found in ankle kinetics, too. Conclusions. This case study highlighted that GA was effective not only to quantify the results of the treatment but also to help preoperative decision making in dealing with CP child.

  20. Bone mineral density test

    Science.gov (United States)

    ... Paula FJA, Black DM, Rosen CJ. Osteoporosis and bone biology.In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology . 13th ed. Philadelphia, ... Bone-density testing interval and transition to osteoporosis in ...

  1. Bone Graft Alternatives

    Science.gov (United States)

    ... cadavers. The types of allograft bone used for spine surgery include fresh frozen and lyophilized (freeze dried). The ... the most common uses of bone grafts in spine surgery is during spinal fusion. The use of autogenous ...

  2. Bone mineral density test

    Science.gov (United States)

    BMD test; Bone density test; Bone densitometry; DEXA scan; DXA; Dual-energy x-ray absorptiometry; p-DEXA; Osteoporosis-BMD ... need to undress. This scan is the best test to predict your risk of fractures. Peripheral DEXA ( ...

  3. Smoking and Bone Health

    Science.gov (United States)

    ... It has been called a childhood disease with old age consequences because building healthy bones in youth helps ... stronger. Weight-bearing exercise that forces you to work against gravity is the best exercise for bone. ...

  4. Bone Loss in IBD

    Science.gov (United States)

    ... DENSITY? Although bone seems as hard as a rock, it’s actually living tissue. Throughout your life, old ... available Bone Loss (.pdf) File: 290 KB 733 Third Avenue, Suite 510, New York, NY 10017 | 800- ...

  5. Bone Marrow Diseases

    Science.gov (United States)

    ... that help with blood clotting. With bone marrow disease, there are problems with the stem cells or ... marrow makes too many white blood cells Other diseases, such as lymphoma, can spread into the bone ...

  6. Nursing care of 38 cases accepting crowns lengthening procedure%38例牙冠延长术病人的护理

    Institute of Scientific and Technical Information of China (English)

    张燕萍; 吴燕萍; 周艳; 吴晓莉

    2011-01-01

    @@ 牙冠延长术(surgical crown lengthening)是近年来在国际、国内逐渐普遍应用的一种牙周手术,其基本原理是根向复位瓣手术加少量的骨切除术,以此来增加牙槽嵴顶以上的牙体组织的长度,保持正常的生物学宽度.

  7. HPV-16 E7 reveals a link between DNA replication stress, FANCD2 and alternative lengthening of telomeres (ALT)-associated PML bodies (APBs)

    OpenAIRE

    Spardy, Nicole; Duensing, Anette; Hoskins, Elizabeth E.; Wells, Susanne I.; Duensing, Stefan

    2008-01-01

    Expression of the high-risk human papillomavirus (HPV-16) E7 oncoprotein extends the life span of primary human keratinocytes and partially restores telomere length in the absence of telomerase. The molecular basis of this activity is incompletely understood. Here, we show that HPV-16 E7 induces an increased formation of alternative lengthening of telomeres (ALT)-associated PML bodies (APBs) in early passage primary human keratinocytes as well as HPV-negative tumor cells. This activity was fo...

  8. Mutant Telomeric Repeats in Yeast Can Disrupt the Negative Regulation of Recombination-Mediated Telomere Maintenance and Create an Alternative Lengthening of Telomeres-Like Phenotype▿

    OpenAIRE

    Bechard, Laura H.; Butuner, Bilge D.; Peterson, George J.; McRae, Will; Topcu, Zeki; McEachern, Michael J.

    2008-01-01

    Some human cancers maintain telomeres using alternative lengthening of telomeres (ALT), a process thought to be due to recombination. In Kluyveromyces lactis mutants lacking telomerase, recombinational telomere elongation (RTE) is induced at short telomeres but is suppressed once telomeres are moderately elongated by RTE. Recent work has shown that certain telomere capping defects can trigger a different type of RTE that results in much more extensive telomere elongation that is reminiscent o...

  9. Modulation of Telomeres in Alternative Lengthening of Telomeres Type I Like Human Cells by the Expression of Werner Protein and Telomerase

    OpenAIRE

    Aisha Siddiqa; David Cavazos; Jeffery Chavez; Linda Long; Marciniak, Robert A.

    2012-01-01

    The alternative lengthening of telomeres (ALT) is a recombination-based mechanism of telomere maintenance activated in 5–20% of human cancers. In Saccharomyces cerevisiae, survivors that arise after inactivation of telomerase can be classified as type I or type II ALT. In type I, telomeres have a tandem array structure, with each subunit consisting of a subtelomeric Y′ element and short telomere sequence. Telomeres in type II have only long telomere repeats and require Sgs1, the S. cerevisiae...

  10. A Mutation in the STN1 Gene Triggers an Alternative Lengthening of Telomere-Like Runaway Recombinational Telomere Elongation and Rapid Deletion in Yeast

    OpenAIRE

    Iyer, Shilpa; Chadha, Ashley D.; McEachern, Michael J.

    2005-01-01

    Some human cancer cells achieve immortalization by using a recombinational mechanism termed ALT (alternative lengthening of telomeres). A characteristic feature of ALT cells is the presence of extremely long and heterogeneous telomeres. The molecular mechanism triggering and maintaining this pathway is currently unknown. In Kluyveromyces lactis, we have identified a novel allele of the STN1 gene that produces a runaway ALT-like telomeric phenotype by recombination despite the presence of an a...

  11. Bone regeneration in dentistry

    OpenAIRE

    Tonelli, Paolo; Duvina, Marco; Barbato, Luigi; Biondi, Eleonora; Nuti, Niccolò; Brancato, Leila; Rose, Giovanna Delle

    2011-01-01

    The edentulism of the jaws and the periodontal disease represent conditions that frequently leads to disruption of the alveolar bone. The loss of the tooth and of its bone of support lead to the creation of crestal defects or situation of maxillary atrophy. The restoration of a functional condition involves the use of endosseous implants who require adequate bone volume, to deal with the masticatory load. In such situations the bone need to be regenerated, taking advantage of the biological p...

  12. BONE MECHANOTRANSDUCTION: A REVIEW

    OpenAIRE

    Reis, Joana; Capela e Silva, Fernando; Queiroga, Cristina; Lucena, Sónia; Potes, José

    2011-01-01

    This review focus on the bone physiology and mechanotransduction elements and mechanisms. Bone biology and architecture is deeply related to the mechanical environment. Orthopaedic implants cause profound changes in the biomechanics and electrophysiology of the skeleton. In the context of biomedical engineering, a deep reflexion on bone physiology and electromechanics is needed. Strategic development of new biomaterials and devices that respect and promote continuity with bone str...

  13. Gracile bone dysplasias

    Energy Technology Data Exchange (ETDEWEB)

    Kozlowski, Kazimierz [Department of Medical Imaging, The Children' s Hospital at Westmead, Locked Bag 4001, Westmead 2145, NSW (Australia); Masel, John [Department of Radiology, Royal Children' s Hospital, Brisbane (Australia); Sillence, David O. [Department of Paediatrics and Child Health, The University of Sydney (Australia); Arbuckle, Susan [Department of Anatomical Pathology, The Children' s Hospital at Westmead, NSW (Australia); Juttnerova, Vera [Oddeleni Lekarske Genetiky, Hradec Kralove (Czech Republic)

    2002-09-01

    Gracile bone dysplasias constitute a group of disorders characterised by extremely slender bones with or without fractures. We report four newborns, two of whom showed multiple fractures. Two babies had osteocraniostenosis and one had features of oligohydramnios sequence. The diagnosis in the fourth newborn, which showed thin long bones and clavicles and extremely thin, poorly ossified ribs, is uncertain. Exact diagnosis of a gracile bone dysplasia is important for genetic counselling and medico-legal reasons. (orig.)

  14. Bone cysts: unicameral and aneurysmal bone cyst.

    Science.gov (United States)

    Mascard, E; Gomez-Brouchet, A; Lambot, K

    2015-02-01

    Simple and aneurysmal bone cysts are benign lytic bone lesions, usually encountered in children and adolescents. Simple bone cyst is a cystic, fluid-filled lesion, which may be unicameral (UBC) or partially separated. UBC can involve all bones, but usually the long bone metaphysis and otherwise primarily the proximal humerus and proximal femur. The classic aneurysmal bone cyst (ABC) is an expansive and hemorrhagic tumor, usually showing characteristic translocation. About 30% of ABCs are secondary, without translocation; they occur in reaction to another, usually benign, bone lesion. ABCs are metaphyseal, excentric, bulging, fluid-filled and multicameral, and may develop in all bones of the skeleton. On MRI, the fluid level is evocative. It is mandatory to distinguish ABC from UBC, as prognosis and treatment are different. UBCs resolve spontaneously between adolescence and adulthood; the main concern is the risk of pathologic fracture. Treatment in non-threatening forms consists in intracystic injection of methylprednisolone. When there is a risk of fracture, especially of the femoral neck, surgery with curettage, filling with bone substitute or graft and osteosynthesis may be required. ABCs are potentially more aggressive, with a risk of bone destruction. Diagnosis must systematically be confirmed by biopsy, identifying soft-tissue parts, as telangiectatic sarcoma can mimic ABC. Intra-lesional sclerotherapy with alcohol is an effective treatment. In spinal ABC and in aggressive lesions with a risk of fracture, surgical treatment should be preferred, possibly after preoperative embolization. The risk of malignant transformation is very low, except in case of radiation therapy. PMID:25579825

  15. Enzymatic maceration of bone

    DEFF Research Database (Denmark)

    Uhre, Marie-Louise; Eriksen, Anne Marie; Simonsen, Kim Pilkjær;

    2015-01-01

    the bones. The DNA analysis showed that DNA was preserved on all the pieces of bones which were examined. Finally, the investigation suggests that enzyme maceration could be gentler on the bones, as the edges appeared less frayed. The enzyme maceration was also a quicker method; it took three hours compared...

  16. What's a Funny Bone?

    Science.gov (United States)

    ... Help White House Lunch Recipes What's a Funny Bone? KidsHealth > For Kids > What's a Funny Bone? Print A A A Text Size Have you ... prickly kind of dull pain? That's your funny bone! It doesn't really hurt as much as ...

  17. Menopause and Bone Loss

    Science.gov (United States)

    Fact Sheet & Menopause Bone Loss How are bone loss and menopause related? Throughout life your body keeps a balance between the loss ... The sooner you take steps to prevent bone loss, the lower your risk of osteoporosis later in life. If you are skipping menstrual periods, have had ...

  18. 超声骨刀在牙冠延长术中的临床应用%Clinical application of the piezosurgery for surgical crown lengthening

    Institute of Scientific and Technical Information of China (English)

    高秀秋; 王冠楠; 张卓

    2012-01-01

    Surgical crown lengthening can reduce the position of the gingival margin, expose health tooth structure, lengthen the clinical crown and favor the denture repair or help to solve aesthetic problems. We conducted surgical corown lengthening operation by piezosurgery in 11 paitnets involving 36 teeth. Health gingiva, stable and coordinatie gingival margin were observed in all cases with all teeth in 6-month follow- up.%牙冠延长术是通过手术的方法,降低龈缘位置、暴露健康的牙齿结构,使临床牙冠加长,从而利于义齿的修复或解决美观问题的一种牙周外科手术.我科采用超声骨刀行牙冠延长术11 例,术后观察6 个月,患牙牙龈健康、稳定、龈缘协调.

  19. Clinical Observations on Crown Lengthening Surgery with Piezosurgery.%超声骨刀在牙冠延长术中的应用效果观察

    Institute of Scientific and Technical Information of China (English)

    杨萍; 高永波; 李绍岳; 骆伟燕; 周利文; 韩琼

    2011-01-01

    目的:评价超声骨刀在牙冠延长术中的应用效果.方法:应用超声骨刀对20例患者的30颗患牙作牙冠延长术,检测术前、术后1周、术后4周患牙龈沟出血指数、缺损最低处探诊深度.结果:30颗患牙在观察期内均获得良好效果,患牙达到桩冠修复的条件.结论:超声骨刀应用于牙冠延长术可获得良好的疗效.%Objective: To evaluate the clinical effects of crown lengthening surgery by piezosurgery.Methods:Thirty teeth from twenty patients underwent crown lengthening surgery by piezosurgery.The sulcus bleeding index (SBI) and maximal defect probing depth (PD) were measured before the surgery as well as 7 days and 28 days later.Results: The clinical effects of surgery were good.The thirty teeth had achieved the indications for post crown.Conclusion: Piezosurgery is an ideal therapeutic method for crown lengthening surgery.

  20. Palms do not undergo secondary stem lengthening: a response to Renninger and Phillips (American Journal of Botany 99: 607-613).

    Science.gov (United States)

    Tomlinson, P Barry; Quinn, Christopher J

    2013-03-01

    Woody stems that have completed some maturation of metaxylem elements should not be capable of further axial extension ("secondary stem lengthening"). However, this mechanism has been claimed by Renninger and Phillips (American Journal of Botany 99: 607-613) to be a feature of the palm Iriartea deltoidea. In response, we describe structural features of palm stems based on extensive known features of their anatomy and development. In addition to the inability of metaxylem vessels to extend after they are mature, fully differentiated fibers of the vascular bundle sheath, which would exist at the time of proposed stem elongation would not be capable of belated extension. "Vessel spirals" claimed by these authors to be capable of stretching to accommodate secondary stem lengthening does not refer to well-established features of the course of vascular bundles. The approach adopted by Renninger and Phillips simply measures stems of different sizes as an implied developmental series. Consequently, results do not take into account changes in the development of the palm stem as it ages. The existence of secondary stem lengthening in the palm Iriartea deltoidea, something never before observed in any tree, cannot occur because it would indeed disrupt mature metaxylem vessels and would also require the secondary extension of mature lignified fibers. PMID:23455481

  1. Tin in Human Bones

    OpenAIRE

    Jambor, Jaroslav; Smreka, Vâclav

    1993-01-01

    TIN IN HUMAN BONES. The tin content in the bones of 149 skeletons from the 1st - 5th centuries A.D., and of 11 individuals of the recent population was determined. The bone samples were carbonized and analyzed through emission spectroscopy with a.c. excitation. The tin content in bones of recent populations not exposed to extra tin supply is about one order of magnitude higher than is the case with the bones od some populations that lived at the beginning of our era. The distribut...

  2. Bone regeneration with cultured human bone grafts

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, T.; Nakajima, H. [Nara Medical Univ., Kashihara City (Japan). Dept. of Pathology; Nara Medical Univ., Kashihara City (Japan). Dept. of Orthopedic Surgery; Ohgushi, H.; Ueda, Y.; Takakura, Y. [Nara Medical Univ., Kashihara City (Japan). Dept. of Orthopedic Surgery; Uemura, T.; Tateishi, T. [National Inst. for Advanced Interdisciplinary Research (NAIR), Ibaraki (Japan). Tsukuba Research Center; Enomoto, Y.; Ichijima, K. [Nara Medical Univ., Kashihara City (Japan). Dept. of Pathology

    2001-07-01

    From 73 year old female patient, 3 ml of bone marrow was collected from the ilium. The marrow was cultured to concentrate and expand the marrow mesenchymal cells on a culture dish. The cultured cells were then subculturedeither on another culture dish or in porous areas of hydroxyapatite ceramics in the presence of dexamethasone and beta-glycerophosphate (osteo genic medium). The subculturedtissues on the dishes were analyzed by scanning electron microscopy (SEM), and subculturedtissues in the ceramics were implanted intraperitoneally into athymic nude mice. Vigorous growth of spindle-shaped cells and a marked formation of bone matrix beneath the cell layers was observed on the subculture dishes by SEM. The intraperitoneally implanted ceramics with cultured tissues revealed thick layer of lamellar bone together with active osteoblasts lining in many pore areas of the ceramics after 8 weeks. The in vitro bone formations on the culture dishes and in vivo bone formation in porous ceramics were detected. These results indicate that we can assemble an in vitro bone/ceramic construct, and due to the porous framework of the ceramic, the construct has osteogenic potential similar to that of autologous cancellous bone. A significant benefit of this method is that the construct can be made with only a small amount of aspirated marrow cells from aged patients with little host morbidity. (orig.)

  3. Bone scintiscanning updated.

    Science.gov (United States)

    Lentle, B C; Russell, A S; Percy, J S; Scott, J R; Jackson, F I

    1976-03-01

    Use of modern materials and methods has given bone scintiscanning a larger role in clinical medicine, The safety and ready availability of newer agents have led to its greater use in investigating both benign and malignant disease of bone and joint. Present evidence suggests that abnormal accumulation of 99mTc-polyphosphate and its analogues results from ionic deposition at crystal surfaces in immature bone, this process being facilitated by an increase in bone vascularity. There is, also, a component of matrix localization. These factors are in keeping with the concept that abnormal scintiscan sites represent areas of increased osteoblastic activity, although this may be an oversimplification. Increasing evidence shows that the bone scintiscan is more sensitive than conventional radiography in detecting focal disease of bone, and its ability to reflect the immediate status of bone further complements radiographic findings. The main limitation of this method relates to nonspecificity of the results obtained.

  4. ALT——端粒延长替代机制%ALT——Alternative lengthening of telomere

    Institute of Scientific and Technical Information of China (English)

    吴晓明; 唐文如; 罗瑛

    2009-01-01

    端粒长度和结构的稳定与肿瘤及衰老的发生密切相关,端粒维持机制是细胞增殖的必要条件,端粒维持机制的激活是肿瘤细胞演化过程中的一个重要环节.这种端粒维持机制可能是通过重新激活端粒酶,使细胞快速增殖.在端粒酶失活或不足的情况下,也存在着一种或多种维持和增加端粒长度的机制,统称为端粒延长替代机制(Alterative lengthening of telomere,ALT).其特点包括:具有不均一的端粒长度,存在与ALT相关的PML小体(APBs)以及同源重组增加.ALT细胞内存在的ALT相关蛋白及异常活跃的同源重组为ALT机制的激活和维持提供了可能.文章综述了ALT的特征性表型、与端粒酶的相关性及其可能的发生机制.对ALT机制的深入研究将有利于阐明衰老与肿瘤之间的辩证关系.

  5. Stable expression of promyelocytic leukaemia (PML protein in telomerase positive MCF7 cells results in alternative lengthening of telomeres phenotype

    Directory of Open Access Journals (Sweden)

    Yong Jacklyn W Y

    2012-08-01

    Full Text Available Abstract Background Cancer cells can employ telomerase or the alternative lengthening of telomeres (ALT pathway for telomere maintenance. Cancer cells that use the ALT pathway exhibit distinct phenotypes such as heterogeneous telomeres and specialised Promyelocytic leukaemia (PML nuclear foci called APBs. In our study, we used wild-type PML and a PML mutant, in which the coiled-coil domain is deleted (PML C/C-, to investigate how these proteins can affect telomere maintenance pathways in cancer cells that use either the telomerase or ALT pathway. Results Stable over-expression of both types of PML does not affect the telomere maintenance in the ALT cells. We report novel observations in PML over-expressed telomerase-positive MCF7 cells: 1 APBs are detected in telomerase-positive MCF7 cells following over-expression of wild-type PML and 2 rapid telomere elongation is observed in MCF7 cells that stably express either wild-type PML or PML C/C-. We also show that the telomerase activity in MCF7 cells can be affected depending on the type of PML protein over-expressed. Conclusion Our data suggests that APBs might not be essential for the ALT pathway as MCF7 cells that do not contain APBs exhibit long telomeres. We propose that wild-type PML can either definitively dominate over telomerase or enhance the activity of telomerase, and PML C/C- can allow for the co-existence of both telomerase and ALT pathways. Our findings add another dimension in the study of telomere maintenance as the expression of PML alone (wild-type or otherwise is able to change the dynamics of the telomerase pathway.

  6. TCEAL7 Inhibition of c-Myc Activity in Alternative Lengthening of Telomeres Regulates hTERT Expression

    Directory of Open Access Journals (Sweden)

    Kyle Lafferty-Whyte

    2010-05-01

    Full Text Available Replicative senescence forms a major barrier to tumor progression. Cancer cells bypass this by using one of the two known telomere maintenance mechanisms: telomerase or the recombination-based alternative lengthening of telomeres (ALT mechanism. The molecular details of ALT are currently poorly understood. We have previously shown that telomerase is actively repressed through complex networks of kinase, gene expression, and chromatin regulation. In this study, we aimed to gain further understanding of the role of kinases in the regulation of telomerase expression in ALT cells. Using a whole human kinome small interfering RNA (siRNA screen, we highlighted 106 kinases whose expression is linked to human telomerase reverse transcriptase (hTERT promoter activity. Network modeling of transcriptional regulation implicated c-Myc as a key regulator of the 106 kinase hits. Given our previous observations of lower c-Myc activity in ALT cells, we further explored its potential to regulate telomerase expression in ALT. We found increased c-Myc binding at the hTERT promoter in telomerase-positive compared with ALT cells, although no expression differences in c-Myc, Mad, or Max were observed between ALT and telomerase-positive cells that could explain decreased c-Myc activity in ALT. Instead, we found increased expression of the c-Myc competitive inhibitor TCEAL7 in ALT cells and tumors and that alteration of TCEAL7 expression levels in ALT and telomerase-positive cells affects hTERT expression. Lower c-Myc activity in ALT may therefore be obtained through TCEAL7 regulation. Thus, TCEAL7 may present an interesting novel target for cancer therapy, which warrants further investigation.

  7. Leiomyosarcoma with alternative lengthening of telomeres is associated with aggressive histologic features, loss of ATRX expression, and poor clinical outcome.

    Science.gov (United States)

    Liau, Jau-Yu; Tsai, Jia-Huei; Jeng, Yung-Ming; Lee, Jen-Chieh; Hsu, Hung-Han; Yang, Ching-Yao

    2015-02-01

    Leiomyosarcoma is an aggressive soft tissue sarcoma with poor patient survival. Recently, it was shown that 53% to 62% of leiomyosarcomas use the alternative lengthening of telomeres (ALT) as their telomere maintenance mechanism. The molecular basis of this mechanism has not been elucidated. Studies of pancreatic neuroendocrine tumor have suggested that the inactivation of either α-thalassemia/mental retardation syndrome X-linked (ATRX) or death domain-associated (DAXX) protein is associated with the ALT phenotype. In this study, we sought to determine the clinicopathologic features of leiomyosarcoma with the ALT phenotype and the possible relationship between this phenotype and ATRX/DAXX expression. Telomerase reverse transcriptase gene (TERT) promoter mutation analysis was also performed. Ninety-two leiomyosarcomas derived from the uterus, retroperitoneum/intra-abdomen, and various other sites were analyzed. Telomere-specific fluorescence in situ hybridization revealed that 59% (51/86) of leiomyosarcomas had the ALT phenotype. Loss of ATRX expression was observed in 33% of the tumors (30/92), and all but 2 ATRX-deficient tumors were ALT positive. Both the ALT phenotype and loss of ATRX expression were associated with epithelioid/pleomorphic cell morphology, tumor necrosis, and poor differentiation. None of the 92 cases lost DAXX expression. No TERT promoter mutation was detected (n=39). For survival analysis, poor differentiation, high FNCLCC grade, tumor size, and ALT phenotype were correlated with poor overall survival in univariate analysis. Tumor size and ALT phenotype remained independent prognostic factors in multivariate analysis. We concluded that the ALT phenotype in the leiomyosarcoma is associated with aggressive histologic features, loss of ATRX expression, and poor clinical outcome. PMID:25229770

  8. HP1-mediated formation of alternative lengthening of telomeres-associated PML bodies requires HIRA but not ASF1a.

    Directory of Open Access Journals (Sweden)

    Wei-Qin Jiang

    Full Text Available Approximately 10% of cancers use recombination-mediated Alternative Lengthening of Telomeres (ALT instead of telomerase to prevent telomere shortening. A characteristic of cells that utilize ALT is the presence of ALT-associated PML nuclear bodies (APBs containing (TTAGGGn DNA, telomere binding proteins, DNA recombination proteins, and heterochromatin protein 1 (HP1. The function of APBs is unknown and it is possible that they are functionally heterogeneous. Most ALT cells lack functional p53, and restoration of the p53/p21 pathway in these cells results in growth arrest/senescence and a substantial increase in the number of large APBs that is dependent on two HP1 isoforms, HP1α and HP1γ. Here we investigated the mechanism of HP1-mediated APB formation, and found that histone chaperones, HIRA and ASF1a, are present in APBs following activation of the p53/p21 pathway in ALT cells. HIRA and ASF1a were also found to colocalize inside PML bodies in normal fibroblasts approaching senescence, providing evidence for the existence of a senescence-associated ASF1a/HIRA complex inside PML bodies, consistent with a role for these proteins in induction of senescence in both normal and ALT cells. Moreover, knockdown of HIRA but not ASF1a significantly reduced p53-mediated induction of large APBs, with a concomitant reduction of large HP1 foci. We conclude that HIRA, in addition to its physical and functional association with ASF1a, plays a unique, ASF1a-independent role, which is required for the localization of HP1 to PML bodies and thus for APB formation.

  9. Biophotonics and Bone Biology

    Science.gov (United States)

    Zimmerli, Gregory; Fischer, David; Asipauskas, Marius; Chauhan, Chirag; Compitello, Nicole; Burke, Jamie; Tate, Melissa Knothe

    2004-01-01

    One of the more-serious side effects of extended space flight is an accelerated bone loss [Bioastronautics Critical Path Roadmap, http://research.hq.nasa.gov/code_u/bcpr/index.cfm]. Rates of bone loss are highest in the weight-bearing bones of the hip and spine regions, and the average rate of bone loss as measured by bone mineral density measurements is around 1.2% per month for persons in a microgravity environment. It shows that an extrapolation of the microgravity induced bone loss rates to longer time scales, such as a 2.5 year round-trip to Mars (6 months out at 0 g, 1.5 year stay on Mars at 0.38 g, 6 months back at 0 g), could severely compromise the skeletal system of such a person.

  10. Bone tumors: Nursing care

    International Nuclear Information System (INIS)

    Bone tumors represent approximately 5% of childhood malignancies. osteosarcoma is the primary malignant bone tumor, accounting for 60% of cancer with peak incidence in the 2nd decade of life. Ewing's sarcoma is the second most common bone cancer with peak at a slightly younger age. This presentation discusses similarities and differences in the diagnosis and treatment of these two malignancies. Diagnostic procedures include plain radiographs, CT and MRI of the primary site, plain x-ray and CT of the chest, bone scan, and biopsy of the primary tumor. For patients diagnosed with Ewing's sarcoma, a bone marrow aspirate and biopsy will also be required. Our current approach to the treatment of bone tumors includes preoperative combination chemotherapy and en bloc surgical removal of the tumor followed by postoperative chemotherapy. In the case of Ewing's sarcoma, radiation therapy may be employed in addition to surgery, if margins are questionable of instead of surgery, if the tumor is not resectable

  11. Bone Regeneration in Odontostomatology

    OpenAIRE

    Tonelli, P; Duvina, M.; Brancato, L.; Delle Rose, G.; Biondi, E.; Civitelli, V.

    2010-01-01

    Maxillary edentulism, together with periodontal disease, is the condition that most frequently induces disruption of alveolar bone tissue. Indeed, the stimulus of the periodontal ligament is lost and the local bone tissue becomes subject to resorption processes that, in the six months following the loss of the tooth, result in alveolar defects or more extensive maxillary atrophy. In both cases, loss of vestibular cortical bone is followed by reduction in the vertical dimension of the alveolar...

  12. Percutaneous Bone Tumor Management

    OpenAIRE

    Gangi, Afshin; Buy, Xavier

    2010-01-01

    Interventional radiology plays a major role in the management of bone tumors. Many different percutaneous techniques are available. Some aim to treat pain and consolidate a pathological bone (cementoplasty); others aim to ablate tumor or reduce its volume (sclerotherapy, thermal ablation). In this article, image-guided techniques of primary and secondary bone tumors with vertebroplasty, ethanol injection, radiofrequency ablation, laser photocoagulation, cryoablation, and radiofrequency ioniza...

  13. Nanocomposites and bone regeneration

    Science.gov (United States)

    James, Roshan; Deng, Meng; Laurencin, Cato T.; Kumbar, Sangamesh G.

    2011-12-01

    This manuscript focuses on bone repair/regeneration using tissue engineering strategies, and highlights nanobiotechnology developments leading to novel nanocomposite systems. About 6.5 million fractures occur annually in USA, and about 550,000 of these individual cases required the application of a bone graft. Autogenous and allogenous bone have been most widely used for bone graft based therapies; however, there are significant problems such as donor shortage and risk of infection. Alternatives using synthetic and natural biomaterials have been developed, and some are commercially available for clinical applications requiring bone grafts. However, it remains a great challenge to design an ideal synthetic graft that very closely mimics the bone tissue structurally, and can modulate the desired function in osteoblast and progenitor cell populations. Nanobiomaterials, specifically nanocomposites composed of hydroxyapatite (HA) and/or collagen are extremely promising graft substitutes. The biocomposites can be fabricated to mimic the material composition of native bone tissue, and additionally, when using nano-HA (reduced grain size), one mimics the structural arrangement of native bone. A good understanding of bone biology and structure is critical to development of bone mimicking graft substitutes. HA and collagen exhibit excellent osteoconductive properties which can further modulate the regenerative/healing process following fracture injury. Combining with other polymeric biomaterials will reinforce the mechanical properties thus making the novel nano-HA based composites comparable to human bone. We report on recent studies using nanocomposites that have been fabricated as particles and nanofibers for regeneration of segmental bone defects. The research in nanocomposites, highlight a pivotal role in the future development of an ideal orthopaedic implant device, however further significant advancements are necessary to achieve clinical use.

  14. Imaging of Bone Marrow.

    Science.gov (United States)

    Lin, Sopo; Ouyang, Tao; Kanekar, Sangam

    2016-08-01

    Bone marrow is the essential for function of hematopoiesis, which is vital for the normal functioning of the body. Bone marrow disorders or dysfunctions may be evaluated by blood workup, peripheral smears, marrow biopsy, plain radiographs, computed tomography (CT), MRI and nuclear medicine scan. It is important to distinguish normal spinal marrow from pathology to avoid missing a pathology or misinterpreting normal changes, either of which may result in further testing and increased health care costs. This article focuses on the diffuse bone marrow pathologies, because the majority of the bone marrow pathologies related to hematologic disorders are diffuse. PMID:27444005

  15. Bone marrow fat.

    Science.gov (United States)

    Hardouin, Pierre; Pansini, Vittorio; Cortet, Bernard

    2014-07-01

    Bone marrow fat (BMF) results from an accumulation of fat cells within the bone marrow. Fat is not a simple filling tissue but is now considered as an actor within bone microenvironment. BMF is not comparable to other fat depots, as in subcutaneous or visceral tissues. Recent studies on bone marrow adipocytes have shown that they do not appear only as storage cells, but also as cells secreting adipokines, like leptin and adiponectin. Moreover bone marrow adipocytes share the same precursor with osteoblasts, the mesenchymal stem cell. It is now well established that high BMF is associated with weak bone mass in osteoporosis, especially during aging and anorexia nervosa. But numerous questions remain discussed: what is the precise phenotype of bone marrow adipocytes? What is the real function of BMF, and how does bone marrow adipocyte act on its environment? Is the increase of BMF during osteoporosis responsible for bone loss? Is BMF involved in other diseases? How to measure BMF in humans? A better understanding of BMF could allow to obtain new diagnostic tools for osteoporosis management, and could open major therapeutic perspectives. PMID:24703396

  16. Biophotonics and Bone Biology

    Science.gov (United States)

    Zimmerli, Gregory; Fischer, David; Asipauskas, Marius; Chauhan, Chirag; Compitello, Nicole; Burke, Jamie; Tate, Melissa Knothe

    2004-01-01

    One of the more serious side effects of extended space flight is an accelerated bone loss. Rates of bone loss are highest in the weight-bearing bones of the hip and spine regions, and the average rate of bone loss as measured by bone mineral density measurements is around 1.2% per month for persons in a microgravity environment. It is well known that bone remodeling responds to mechanical forces. We are developing two-photon microscopy techniques to study bone tissue and bone cell cultures to better understand the fundamental response mechanism in bone remodeling. Osteoblast and osteoclast cell cultures are being studied, and the goal is to use molecular biology techniques in conjunction with Fluorescence Lifetime Imaging Microscopy (FLIM) to study the physiology of in-vitro cell cultures in response to various stimuli, such as fluid flow induced shear stress and mechanical stress. We have constructed a two-photon fluorescence microscope for these studies, and are currently incorporating FLIM detection. Current progress will be reviewed. This work is supported by the NASA John Glenn Biomedical Engineering Consortium.

  17. Hypercalciuric Bone Disease

    Science.gov (United States)

    Favus, Murray J.

    2008-09-01

    Hypercalciuria plays an important causal role in many patients with calcium oxalate (CaOx) stones. The source of the hypercalciuria includes increased intestinal Ca absorption and decreased renal tubule Ca reabsorption. In CaOx stone formers with idiopathic hypercalciuria (IH), Ca metabolic balance studies have revealed negative Ca balance and persistent hypercalciuria in the fasting state and during low dietary Ca intake. Bone resorption may also contribute to the high urine Ca excretion and increase the risk of bone loss. Indeed, low bone mass by DEXA scanning has been discovered in many IH patients. Thiazide diuretic agents reduce urine Ca excretion and may increase bone mineral density (BMD), thereby reducing fracture risk. Dietary Ca restriction that has been used unsuccessfully in the treatment of CaOx nephrolithiasis in the past may enhance negative Ca balance and accelerate bone loss. DEXA scans may demonstrate low BMD at the spine, hip, or forearm, with no predictable pattern. The unique pattern of bone histologic changes in IH differs from other causes of low DEXA bone density including postmenopausal osteoporosis, male hypogonadal osteoporosis, and glucocorticoid-induced osteoporosis. Hypercalciuria appears to play an important pathologic role in the development of low bone mass, and therefore correction of urine Ca losses should be a primary target for treatment of the bone disease accompanying IH.

  18. 超声骨刀应用于牙冠延长术的疗效观察%Observation on the curative effect of crown lengthening surgery with piezosurgery

    Institute of Scientific and Technical Information of China (English)

    步中琦; 顾海佳; 姚斯琦

    2015-01-01

    effect on patients who need crown lengthening surgery to recover the subgingival tooth defects. At the same time, piezosurgery causes less bone loss, smaller periodontal wound and the better recovery.

  19. A randomised controlled trial of a lengthened and multi-disciplinary consultation model in a socially deprived community: a study protocol.

    LENUS (Irish Health Repository)

    Whitford, David L

    2007-01-01

    BACKGROUND: There has been little development of the general practice consultation over the years, and many aspects of the present consultation do not serve communities with multiple health and social problems well. Many of the problems presenting to general practitioners in socio-economically disadvantaged areas are not amenable to a purely medical solution, and would particularly benefit from a multidisciplinary approach. Socio-economic deprivation is also associated with those very factors (more psychosocial problems, greater need for health promotion, more chronic diseases, more need for patient enablement) that longer consultations have been shown to address. This paper describes our study protocol, which aims to evaluate whether a lengthened multidisciplinary primary care team consultation with families in a socially deprived area can improve the psychological health of mothers in the families. METHODS\\/DESIGN: In a randomised controlled trial, families with a history of social problems, substance misuse or depression are randomly allocated to an intervention or control group. The study is based in three general practices in a highly deprived area of North Dublin. Primary health care teams will be trained in conducting a multidisciplinary lengthened consultation. Families in the intervention group will participate in the new style multidisciplinary consultation. Outcomes of families receiving the intervention will be compared to the control group who will receive only usual general practitioner care. The primary outcome is the psychological health of mothers of the families and secondary outcomes include general health status, quality of life measures and health service usage. DISCUSSION: The main aim of this study is to evaluate the effectiveness of a lengthened multidisciplinary team consultation in primary care. The embedded nature of this study in general practices in a highly deprived area ensures generalisability to other deprived communities, but more

  20. Bayesian analysis of the species-specific lengthening of the growing season in two European countries and the influence of an insect pest

    Science.gov (United States)

    Menzel, Annette; Estrella, Nicole; Heitland, Werner; Susnik, Andreja; Schleip, Christoph; Dose, Volker

    2008-01-01

    A recent lengthening of the growing season in mid and higher latitudes of the northern hemisphere is reported as a clear indicator for climate change impacts. Using data from Germany (1951-2003) and Slovenia (1961-2004), we study whether changes in the start, end, and length of the growing season differ among four deciduous broad-leaved tree species and countries, how the changes are related to temperature changes, and what might be the confounding effects of an insect attack. The functional behaviour of the phenological and climatological time series and their trends are not analysed by linear regression, but by a new Bayesian approach taking into account different models for the functional description (one change-point, linear, constant models). We find advanced leaf unfolding in both countries with the same species order (oak > horse chestnut, beech, and birch). However, this advance is non linear over time and more apparent in Germany with clear change-points in the late 1970s, followed by marked advances (on average 3.67 days decade-1 in the 2000s). In Slovenia, we find a more gradual advance of onset dates (on average 0.8 days decade-1 in the 2000s). Leaf colouring of birch, beech, and oak has been slightly delayed in the last 3 decades, especially in Germany, however with no clear functional behaviour. Abrupt changes in leaf colouring dates of horse chestnut with recent advancing onset dates can be linked across countries to damage by a newly emerging pest, the horse chestnut leaf-miner ( Cameraria ohridella). The lengthening of the growing season, more distinct in Germany than in Slovenia (on average 4.2 and 1.0 days decade-1 in the 2000s, respectively), exhibits the same species order in both countries (oak > birch > beech). Damage by horse chestnut leaf-miner leads to reduced lengthening (Germany) and drastic shortening (Slovenia) of the horse chestnut growing season (-12 days decade-1 in the 2000s). Advanced spring leaf unfolding and lengthening of the

  1. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... diagnosis of bone cancer . locate foreign objects in soft tissues around or in bones. top of page How ... Dense bone absorbs much of the radiation while soft tissue, such as muscle, fat and organs, allow more ...

  2. Bone marrow (stem cell) donation

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000839.htm Bone marrow (stem cell) donation To use the sharing ... stem cells from a donor's blood. Types of Bone Marrow Donation There are two types of bone ...

  3. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... or in bones. top of page How should I prepare? Most bone x-rays require no special ... to 10 minutes. top of page What will I experience during and after the procedure? A bone ...

  4. Bone Marrow Aspiration and Biopsy

    Science.gov (United States)

    ... Global Sites Search Help? Bone Marrow Aspiration and Biopsy Share this page: Was this page helpful? Also ... Examination Formal name: Bone Marrow Aspiration; Bone Marrow Biopsy Related tests: Complete Blood Count ; WBC Differential ; Reticulocyte ...

  5. Exercise for Your Bone Health

    Science.gov (United States)

    ... supported by your browser. Home Bone Basics Lifestyle Exercise for Your Bone Health Publication available in: PDF ( ... A Complete Osteoporosis Program For Your Information Why Exercise? Like muscle, bone is living tissue that responds ...

  6. BONES, TEACHER'S GUIDE.

    Science.gov (United States)

    Elementary Science Study, Newton, MA.

    THIS GUIDE WAS DEVELOPED FOR USE WITH THE ELEMENTARY SCIENCE STUDY UNIT ON "BONES.""BONES" HAS BEEN TAUGHT IN THE FOURTH GRADE AND REQUIRES FROM 10 TO 25 LESSONS, DEPENDING ON THE NUMBER OF ACTIVITIES USED. THE GUIDE DOES NOT PROVIDE DETAILED INSTRUCTION FOR CONDUCTING CLASSES, BUT RATHER SOME POSSIBLE ACTIVITIES, AND LEAVES THE DAY-TO-DAY…

  7. Wnt Signaling in Bone

    Science.gov (United States)

    Kubota, Takuo; Michigami, Toshimi; Ozono, Keiichi

    2010-01-01

    Wnt signaling is involved not only in embryonic development but also in maintenance of homeostasis in postnatal tissues. Multiple lines of evidence have increased understanding of the roles of Wnt signaling in bone since mutations in the LRP5 gene were identified in human bone diseases. Canonical Wnt signaling promotes mesenchymal progenitor cells to differentiate into osteoblasts. The canonical Wnt/β-catenin pathway possibly through Lrp6, a co-receptor for Wnts as well as Lrp5, in osteoblasts regulates bone resorption by increasing the OPG/RANKL ratio. However, endogenous inhibitors of Wnt signaling including sclerostin block bone formation. Regulation of sclerostin appears to be one of the mechanisms of PTH anabolic actions on bone. Since sclerostin is almost exclusively expressed in osteocytes, inhibition of sclerostin is the most promising design. Surprisingly, Lrp5 controls bone formation by inhibiting serotonin synthesis in the duodenum, but not by directly promoting bone formation. Pharmacological intervention may be considered in many components of the canonical Wnt signaling pathway, although adverse effects and tumorigenicity to other tissues are important. More studies will be needed to fully understand how the Wnt signaling pathway actually influences bone metabolism and to assure the safety of new interventions. PMID:23926379

  8. Osteotransductive bone cements.

    Science.gov (United States)

    Driessens, F C; Planell, J A; Boltong, M G; Khairoun, I; Ginebra, M P

    1998-01-01

    Calcium phosphate bone cements (CPBCs) are osteotransductive, i.e. after implantation in bone they are transformed into new bone tissue. Furthermore, due to the fact that they are mouldable, their osteointegration is immediate. Their chemistry has been established previously. Some CPBCs contain amorphous calcium phosphate (ACP) and set by a sol-gel transition. The others are crystalline and can give as the reaction product dicalcium phosphate dihydrate (DCPD), calcium-deficient hydroxyapatite (CDHA), carbonated apatite (CA) or hydroxyapatite (HA). Mixed-type gypsum-DCPD cements are also described. In vivo rates of osteotransduction vary as follows: gypsum-DCPD > DCPD > CDHA approximately CA > HA. The osteotransduction of CDHA-type cements may be increased by adding dicalcium phosphate anhydrous (DCP) and/or CaCO3 to the cement powder. CPBCs can be used for healing of bone defects, bone augmentation and bone reconstruction. Incorporation of drugs like antibiotics and bone morphogenetic protein is envisaged. Load-bearing applications are allowed for CHDA-type, CA-type and HA-type CPBCs as they have a higher compressive strength than human trabecular bone (10 MPa).

  9. Deceleration in maturation of bone during adolescent age in achondroplasia - a retrospective study using RUS scoring system

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Suk-Ha [Konkuk University Hospital, Department of Orthopedics, Seoul (Korea); Modi, Hitesh N.; Suh, Seung Woo [Korea University Guro Hospital, Scoliosis Research Institute, Department of Orthopedics, Seoul (Korea); Song, Hae-Ryong; Hazra, Sunit; Modi, Chetna [Korea University Guro Hospital, Rare Disease Institute, Department of Orthopedics, Seoul (Korea)

    2009-02-15

    Knowledge of bone age in achondroplasia is required for the prediction of adult height, timings of limb lengthening, and epiphysiodesis procedures. The purpose of this investigation was to determine the differences in skeletal age in achondroplasia and a control population with the Tanner-Whitehouse 3 method using the RUS score and to determine the right age for the interventional procedure for limb lengthening procedure or deformity correction in these patients. Left hand radiographs of 34 patients (age range, 5-18 years) with achondroplasia were evaluated for skeletal age using the RUS scoring system, which were compared with the left hand radiographs of 41 patients (age range, 5-18 years) without achondroplasia measuring skeletal age. The difference in chronological age and RUS bone age were evaluated statistically according to gender and age group. In the achondroplasia group, chronological age were 10.5{+-}4.3 years for males and 10.1{+-}3.6 years for females and RUS bone age were 9.2{+-}4.0 years for males and 8.9{+-}3.4 years for females, which showed statistically significantly difference (males p=0.0003 and females p < 0.0001), while in the control group, chronological age were 11.1{+-}2.9 years for males and 10.7{+-}3.4 years for females and RUS bone age were 11.2{+-}3.4 years for males and 10.7{+-}3.3 years for females, which did not show statistically significantly difference (males p=0.54 and females p=0.76). Our finding suggested a delay of 1.4 years for males and 1.2 years for females in the maturation of bone in achondroplasia patients. Difference between chronological age and RUS bone age was 0.9{+-}1.1 for <10 years and 1.6{+-}0.9 for >10 years in the study group, while 0.1{+-}1.1 for <10 years and -0.2 {+-} 0.6 for >10 years in the control group, which also showed >statistically significant difference (<10 years p=0.04 and >10 years p<0.0001). These differences indicate that there was a delay in the maturation of bones by 1 year in the group <10

  10. Finite element analysis of the maxillary central incisor with crown lengthening surgery and post-core restoration in management of crown-root fracture%上颌中切牙冠根折行冠延长术并桩核冠修复的三维有限元分析

    Institute of Scientific and Technical Information of China (English)

    甄敏; 胡文杰; 荣起国

    2015-01-01

    Objective:To construct the finite element models of maxillary central incisor and the simu-lations with crown lengthening surgery and post-core restoration in management of different crown-root fracture types, to investigate the stress intensity and distributions of these models mentioned above, and to analyze the indications of crown lengthening from the point of view of mechanics. Methods:An extrac-ted maxillary central incisor and alveolar bone plaster model were scanned by Micro-CT and dental impression scanner ( 3shape D700 ) respectively. Then the 3D finite element models of the maxillary central incisor and 9 simulations with crown lengthening surgery and post-core restoration were construc-ted by Mimics 10. 0, Geomagic studio 9. 0 and ANSYS 14. 0 software. The oblique static force (100 N) was applied to the palatal surface ( the junctional area of the incisal 1/3 and middle 1/3 ) , at 45 degrees to the longitudinal axis, then the von Mises stress of dentin, periodontal ligament, alveolar bone, post and core, as well as the periodontal ligament area, were calculated. Results:A total of 10 high-precision three-dimensional finite element models of maxillary central incisor were established. The von Mises stress of models: post >dentin >alveolar bone >core >periodontal ligament, and the von Mises stress increased linearly with the augmentation of fracture degree ( besides the core) . The periodontal ligament area of the crown lengthening was reduced by 12% to 33%. The von Mises stress of periodontal ligament of the B2L2c, B2L3c, B3L1c, B3L2c, B3L3c models exceeded their threshold limit value, respective-ly. Conclusion: The maxillary central incisors with the labial fracture greater than three-quarter crown length and the palatal fracture deeper than 1 mm below the alveolar crest are not the ideal indications of the crown lengthening surgery.%目的:构建上颌中切牙及其不同冠根折类型牙冠延长术后桩核冠修复的三维有限元模型,研究

  11. Neural crest-mediated bone resorption is a determinant of species-specific jaw length.

    Science.gov (United States)

    Ealba, Erin L; Jheon, Andrew H; Hall, Jane; Curantz, Camille; Butcher, Kristin D; Schneider, Richard A

    2015-12-01

    Precise control of jaw length during development is crucial for proper form and function. Previously we have shown that in birds, neural crest mesenchyme (NCM) confers species-specific size and shape to the beak by regulating molecular and histological programs for the induction and deposition of cartilage and bone. Here we reveal that a hitherto unrecognized but similarly essential mechanism for establishing jaw length is the ability of NCM to mediate bone resorption. Osteoclasts are considered the predominant cells that resorb bone, although osteocytes have also been shown to participate in this process. In adults, bone resorption is tightly coupled to bone deposition as a means to maintain skeletal homeostasis. Yet, the role and regulation of bone resorption during growth of the embryonic skeleton have remained relatively unexplored. We compare jaw development in short-beaked quail versus long-billed duck and find that quail have substantially higher levels of enzymes expressed by bone-resorbing cells including tartrate-resistant acid phosphatase (TRAP), Matrix metalloproteinase 13 (Mmp13), and Mmp9. Then, we transplant NCM destined to form the jaw skeleton from quail to duck and generate chimeras in which osteocytes arise from quail donor NCM and osteoclasts come exclusively from the duck host. Chimeras develop quail-like jaw skeletons coincident with dramatically elevated expression of TRAP, Mmp13, and Mmp9. To test for a link between bone resorption and jaw length, we block resorption using a bisphosphonate, osteoprotegerin protein, or an MMP13 inhibitor, and this significantly lengthens the jaw. Conversely, activating resorption with RANKL protein shortens the jaw. Finally, we find that higher resorption in quail presages their relatively lower adult jaw bone mineral density (BMD) and that BMD is also NCM-mediated. Thus, our experiments suggest that NCM not only controls bone resorption by its own derivatives but also modulates the activity of mesoderm

  12. 改良牙冠延长术与正畸牵引加牙冠延长术对上前牙复杂根折治疗效果的比较%Comparison of curative effects between modified crown lengthening surgery and orthodontic traction combined with crown lengthening surgery in the treatment of maxillary anterior teeth complex root fracture

    Institute of Scientific and Technical Information of China (English)

    李新; 马科院

    2014-01-01

    目的:探讨改良牙冠延长术与正畸牵引加牙冠延长术对上前牙复杂根折的治疗效果。方法80例上前牙复杂根折患者,依据治疗措施不同进行临床分组,治疗Ⅰ组40例,采用单独牙冠延长术治疗;治疗Ⅱ组40例,采用正畸牵引联合牙冠延长术治疗。观察两组疗效。结果治疗Ⅱ组上前牙复杂根折患者美学效果评分和功能满意评分明显优于治疗Ⅰ组,差异均有统计学意义(P<0.05)。结论正畸牵引加牙冠延长术对上前牙复杂根折治疗效果明显,预后良好,值得临床推广应用。%Objective To investigate the curative effects between modified crown lengthening surgery and orthodontic traction combined with crown lengthening surgery in the treatment of maxillary anterior teeth complex root fracture. Methods A total of 80 patients with maxillary anterior teeth complex root fracture were divided into groups according to different treatment measures. The treatmentⅠgroup (n=40) received crown lengthening surgery for treatment alone, and the treatmentⅡgroup (n=40) received orthodontic traction combined with crown lengthening surgery for treatment. The curative effects of the two groups were observed. Results The aesthetic score and functional satisfaction score of the treatment Ⅱgroup were better than those of the treatment Ⅰgroup, and the difference had statistical significance (P<0.05). Conclusion Orthodontic traction combined with crown lengthening surgery can provide good curative effect and prognosis in the treatment of maxillary anterior teeth complex root fracture, and it is worthy of clinical application and promotion.

  13. Enzymatic maceration of bone

    DEFF Research Database (Denmark)

    Uhre, Marie-Louise; Eriksen, Anne Marie; Simonsen, Kim Pilkjær;

    2015-01-01

    This proof of concept study investigates the removal of soft tissue from human ribs with the use of two common methods: boiling with a laundry detergent and using enzymes. Six individuals were autopsied, and one rib from each individual was removed for testing. Each rib was cut into pieces...... the bones. The DNA analysis showed that DNA was preserved on all the pieces of bones which were examined. Finally, the investigation suggests that enzyme maceration could be gentler on the bones, as the edges appeared less frayed. The enzyme maceration was also a quicker method; it took three hours compared...

  14. Periodontal bone lesions

    International Nuclear Information System (INIS)

    In the course of life the periodontum is subject to changes which may be physiological or pathological. Intraoral radiographs give insight into the hard structures of the dentomaxillar region and provides information on lesions in the bone of the periodontum in that they show radiopacities and radiolucencies caused by such lesions. In this thesis the relation is investigated between the true shape and dimensions of periodontal bone lesions and their radiographic images. A method is developed and tested of making standardized and reproducible radiographs suitable for longitudinal studies of periodontal lesions. Also the possibility is demonstrated of an objective and reproducible interpretation of radiographic characteristics of periodontal bone lesions. (Auth.)

  15. Acidic microenvironment and bone pain in cancer-colonized bone

    OpenAIRE

    Yoneda, Toshiyuki; Hiasa, Masahiro; Nagata, Yuki; Okui, Tatsuo; White, Fletcher A.

    2015-01-01

    Solid cancers and hematologic cancers frequently colonize bone and induce skeletal-related complications. Bone pain is one of the most common complications associated with cancer colonization in bone and a major cause of increased morbidity and diminished quality of life, leading to poor survival in cancer patients. Although the mechanisms responsible for cancer-associated bone pain (CABP) are poorly understood, it is likely that complex interactions among cancer cells, bone cells and periphe...

  16. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small dose ... limitations of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is ...

  17. Interparietal bones in Nigerian skulls.

    OpenAIRE

    Saxena, S. K.; Chowdhary, D S; Jain, S P

    1986-01-01

    The study was conducted on 40 adult Nigerian skulls which were examined for the presence of interparietal and pre-interparietal bones. Only one interparietal bone was found (2.5% of the present series) while a single pre-interparietal bone was found in four skulls (10%) and multiple pre-interparietal bones in one skull (2.5%).

  18. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very ... of Bone X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive ...

  19. Osteomyelitis of frontal bone

    OpenAIRE

    Chaturvedil, V. N.; Raizada, R. M.; Singh, A. K. Kennedy; Puttewar, M. P.; Bali, S.

    2004-01-01

    A case of Osteomyelitis of the frontal bone with a subperiosteal absces s, an extrudural abscess and a frontal sinus fistula is presented here for its rarity. A brief review of literature and management of the condition is also discussed.

  20. Proximal Tibial Bone Graft

    Science.gov (United States)

    ... Complications Potential problems after a PTBG include infection, fracture of the proximal tibia and pain related to the procedure. Frequently Asked Questions If proximal tibial bone graft is taken from my knee, will this prevent me from being able to ...

  1. Bone healing: little secrets

    OpenAIRE

    Einhorn, T. A.

    2011-01-01

    The development of new strategies to enhance the healing of fractures continues to evolve with the introduction of both locally and systemically delivered compounds. The recent refinement in the use of autologous bone marrow as a bone graft material has brought the field of stem cell biology into orthopaedic practice. New recombinant peptides such as platelet- derived growth factor and teriparatide show promise as local and systemic enhancers respectively. Finally, recent evidence that mutati...

  2. Small Animal Bone Biomechanics

    OpenAIRE

    Vashishth, Deepak

    2008-01-01

    Animal models, in particular mice, offer the possibility of naturally achieving or genetically engineering a skeletal phenotype associated with disease and conducting destructive fracture tests on bone to determine the resulting change in bone’s mechanical properties. Several recent developments, including nano- and micro- indentation testing, microtensile and microcompressive testing, and bending tests on notched whole bone specimens, offer the possibility to mechanically probe small animal ...

  3. SHEEP TEMPORAL BONE

    Directory of Open Access Journals (Sweden)

    Kesavan

    2016-03-01

    Full Text Available INTRODUCTION Human temporal bones are difficult to procure now a days due to various ethical issues. Sheep temporal bone is a good alternative due to morphological similarities, easy to procure and less cost. Many middle ear exercises can be done easily and handling of instruments is done in the procedures like myringoplasty, tympanoplasty, stapedotomy, facial nerve dissection and some middle ear implants. This is useful for resident training programme.

  4. FRACTURE NASAL BONES

    OpenAIRE

    Balasubramanian Thaigarajan; Venkatesan Ulaganathan

    2013-01-01

    Nose is the most prominent part of the face, hence it is likely to be the most common structure to be injured in the face. Although fractures involving the nasal bones are very common, it is often ignored by the patient. Patients with fractures of nasal bone will have deformity, tenderness, haemorrhage, edema, ecchymosis, instability, and crepitation. These features may be present in varying combinations. This article discusses the pathophysiology of these fractures, role of radiography a...

  5. Fracture Nasal Bone

    OpenAIRE

    Balasubramanian, Thiagarajan; Venkatesan, Ulaganathan

    2013-01-01

    Nose is the most prominent part of the face, hence it is likely to be the most common structure to be injured in the face. Although fractures involving the nasal bones are very common, it is often ignored by the patient. Patients with fractures of nasal bone will have deformity, tenderness, haemorrhage, edema, ecchymosis, instability, and crepitation. These features may be present in varying combinations. This article discusses the pathophysiology of these fractures, role of radiography and u...

  6. A comparative study of the clinical effects on the treatment of the subgingival defects of the upper anterior teeth by modified crown lengthening surgery and by crown lengthening surgery with orthodontic traction%改良牙冠延长术与正畸牵引加牙冠延长术治疗上前牙龈下牙体缺损的疗效比较

    Institute of Scientific and Technical Information of China (English)

    雷琼; 陈燕

    2012-01-01

    Objective The purpose of the study is to compare the clinical effects on the treatment of the subgingival defect of the upper anterior teeth by modified crown lengthening surgery and by crown lengthening surgery with Orthodontic traction. Methods 54 upper anterior teeth from 46 patients were divided into two groups randomly, including 27 teeth in the observation group treated by crown lengthening surgery with orthodontic traction and 27 in the control group treated by modified crown lengthening surgery. The difference of indexes before and after treatment in the two groups. Results The indexes such as PPD, GI and TM were improved statistically after treatment ( P 0.05 ) . Conclusion Both the modified crown lengthening surgery and the crown lengthening surgery with orthodontic traction can be applied to treat the subgingival defect of the upper anterior teeth.[ Key words ] modified crown lengthening surgery; crown lengthening surgery with orthodontic traction; subgingival defects%目的 比较改良牙冠延长术与正畸牵引加牙冠延长术对上前牙龈下牙体缺损的治疗效果.方法 选择上前牙龈下牙体缺损患者46例(54颗牙),随机均分为两组.对照组采用改良牙冠延长术治疗,观察组采用正畸牵引加牙冠延长术治疗.比较治疗前后两组患者治疗后各指标的差异.结果 与治疗前比较,两组患者PPD、GI、TM等指标均有不同程度的改善,差异有统计学意义(P<0.05).两组患者之间比较,差异无统计学意义(P>0.05).结论 改良牙冠延长术与正畸牵引加牙冠延长术对上前牙龈下牙体缺损均有较好的治疗效果,临床工作中可根据患者情况选择使用.

  7. Bone Metabolism in Anorexia Nervosa

    OpenAIRE

    Fazeli, Pouneh K.; Klibanski, Anne

    2014-01-01

    Anorexia nervosa (AN), a psychiatric disorder predominantly affecting young women, is characterized by self-imposed chronic nutritional deprivation and distorted body image. AN is associated with a number of medical co-morbidities including low bone mass. The low bone mass in AN is due to an uncoupling of bone formation and bone resorption, which is the result of hormonal adaptations aimed at decreasing energy expenditure during periods of low energy intake. Importantly, the low bone mass in ...

  8. Recombinant human bone morphogenetic protein induces bone formation

    International Nuclear Information System (INIS)

    The authors have purified and characterized active recombinant human bone morphogenetic protein (BMP) 2A. Implantation of the recombinant protein in rats showed that a single BMP can induce bone formation in vivo. A dose-response and time-course study using the rat ectopic bone formation assay revealed that implantation of 0.5-115 μg of partially purified recombinant human BMP-2A resulted in cartilage by day 7 and bone formation by day 14. The time at which bone formation occurred was dependent on the amount of BMP-2A implanted; at high doses bone formation could be observed at 5 days. The cartilage- and bone-inductive activity of the recombinant BMP-2A is histologically indistinguishable from that of bone extracts. Thus, recombinant BMP-2A has therapeutic potential to promote de novo bone formation in humans

  9. Porous surface modified bioactive bone cement for enhanced bone bonding.

    Directory of Open Access Journals (Sweden)

    Qiang He

    Full Text Available BACKGROUND: Polymethylmethacrylate bone cement cannot provide an adhesive chemical bonding to form a stable cement-bone interface. Bioactive bone cements show bone bonding ability, but their clinical application is limited because bone resorption is observed after implantation. Porous polymethylmethacrylate can be achieved with the addition of carboxymethylcellulose, alginate and gelatin microparticles to promote bone ingrowth, but the mechanical properties are too low to be used in orthopedic applications. Bone ingrowth into cement could decrease the possibility of bone resorption and promote the formation of a stable interface. However, scarce literature is reported on bioactive bone cements that allow bone ingrowth. In this paper, we reported a porous surface modified bioactive bone cement with desired mechanical properties, which could allow for bone ingrowth. MATERIALS AND METHODS: The porous surface modified bioactive bone cement was evaluated to determine its handling characteristics, mechanical properties and behavior in a simulated body fluid. The in vitro cellular responses of the samples were also investigated in terms of cell attachment, proliferation, and osteoblastic differentiation. Furthermore, bone ingrowth was examined in a rabbit femoral condyle defect model by using micro-CT imaging and histological analysis. The strength of the implant-bone interface was also investigated by push-out tests. RESULTS: The modified bone cement with a low content of bioactive fillers resulted in proper handling characteristics and adequate mechanical properties, but slightly affected its bioactivity. Moreover, the degree of attachment, proliferation and osteogenic differentiation of preosteoblast cells was also increased. The results of the push-out test revealed that higher interfacial bonding strength was achieved with the modified bone cement because of the formation of the apatite layer and the osseointegration after implantation in the bony

  10. Virtual Temporal Bone Anatomy

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Background The Visible Human Project(VHP) initiated by the U.S. National Library of Medicine has drawn much attention and interests from around the world. The Visible Chinese Human (VCH) project has started in China. The current study aims at acquiring a feasible virtual methodology for reconstructing the temporal bone of the Chinese population, which may provide an accurate 3-D model of important temporal bone structures that can be used in teaching and patient care for medical scientists and clinicians. Methods A series of sectional images of the temporal bone were generated from section slices of a female cadaver head. On each sectional image, SOIs (structures of interest) were segmented by carefully defining their contours and filling their areas with certain gray scale values. The processed volume data were then inducted into the 3D Slicer software(developed by the Surgical Planning Lab at Brigham and Women's Hospital and the MIT AI Lab) for resegmentation and generation of a set of tagged images of the SOIs. 3D surface models of SOIs were then reconstructed from these images. Results The temporal bone and structures in the temporal bone, including the tympanic cavity, mastoid cells, sigmoid sinus and internal carotid artery, were successfully reconstructed. The orientation of and spatial relationship among these structures were easily visualized in the reconstructed surface models. Conclusion The 3D Slicer software can be used for 3-dimensional visualization of anatomic structures in the temporal bone, which will greatly facilitate the advance of knowledge and techniques critical for studying and treating disorders involving the temporal bone.

  11. Comparison of treatment effects of modified crown lengthening surgery and orthodontic traction with crown lengthening surgery on the maxillary anterior teeth complex root fracture%改良牙冠延长术与正畸牵引加牙冠延长术对上前牙复杂根折治疗效果的比较

    Institute of Scientific and Technical Information of China (English)

    李军科; 程瑞卿

    2011-01-01

    目的 比较改良牙冠延长术与正畸牵引+牙冠延长术对上前牙复杂根折的治疗效果.方法 选取60颗牙体缺损达龈下4.Omm以上的具有保留价值的上颌前牙,随机均分为两组,每组30颗患牙,分别采用改良牙冠延长术和正畸牵引+牙冠延长术,分别记录术前、术后一周及修复后6个月的牙周探诊深度(PD)、龈沟出血指数(SBI)、牙齿松动度(TM),观察临床效果.结果 两组病例术后及修复后PD、SBI明显改善,有显著性差异(P<0.05),组间比较,无显著性差异(P>0.05).结论 两种术式对上前牙复杂根折病例均能取得较好的治疗效果.%Objective To compare the effects of modified crown lengthening surgery and orthodontic traction with crown lengthening surgery on the maxillary anterior teeth complex root fracture.Methods Sixty maxillary anterior complicated root fracture teeth with from the lowest site tooth defect to the gingival margin > 4.0mm, which can be preserved, were selected and respectively divided into two groups, and each group have 30 tooth.The modified crown lengthening surgery and onhodontics traction with crown lengthening surgery was used in the two groups respectively.The probing depth ( PD) , sulcus bleeding index ( SBI) , tooth mobility ( TM) were recorded before operation, at 7 day after operation and on six month after resloration of tooth.Results PD, SBI were decreased signiricantly at 7 day after operation and on six month after restoration in the two groups ( P < 0.05).There was no significant difference in comparison between groups ( P > 0.05).Conclusion Cood effect was obtained in using the both two methods on the maxillary anterior teeth complex root fracture.

  12. Differences in lower limb bone mineral density in children with anisomelia.

    Science.gov (United States)

    Wroński, Sławomir; Gaździk, Tadeusz S; Kaleta, Marek; Kotas-Strzoda, Justyna

    2002-12-30

    Background. Lower limb discrepancy (anisomelia) can be caused by many different factors leading to shortening (90% of cases) or lengthening of a limb (10% cases). This article present the results of densitometric tests performed on patients treated for lower limb discrepancy in the Department of Orthopedic of the Silesian Academy of Medicine in the years 1997-1998. Material and methods. Our research involved 57 patients, 31 girls and 26 boys. The Ilizarov technique was used to lengthen 33 femurs and 24 tibias. The average discrepancy was 45 mm (48 mm in the femurs and 42 mm in the tibias), and the patients average age was 13,8 years (range 7-26). The test were performed with a DPX apparatus by the Lumar Corporation. The bone mineral density (BMD) was measured in the area of the shortened limb segment and compared to the results of the analogous measurement of the opposite limb. The height of the measurement frame was 50 mm, and the width was equal to the width of the bone. The measurement field was located in each case at a distance of 3-4 cm (on the respective bone) from the line of the knee joint, in order to eliminate additional density caused by growth cartilage and the imposition of the patella. The repeatability of the tests was assured by a support maintaining constant internal limb rotation of 400. Results. A difference in BMD between the shorter limb and the opposite limb was found in 47 children (82,5%). The average was 16,5%, whereas it was higher in the shorter femurs (19,1%, range 4,5 - 68,5%) than in the tibia (14%, 5,2 - 59,8%). A greater degree of demineralization was found in the girls (23,5%) than in the boys (20%). No correlation was found between the etiology of the shortening and the degree of calcification. Conclusions. The results of these tests may have great significance in the case of densitometric monitoring of regenerated bone being formed in the course of lower limb by the Ilizarow method.

  13. Periostin action in bone.

    Science.gov (United States)

    Bonnet, Nicolas; Garnero, Patrick; Ferrari, Serge

    2016-09-01

    Periostin is a highly conserved matricellular protein that shares close homology with the insect cell adhesion molecule fasciclin 1. Periostin is expressed in a broad range of tissues including the skeleton, where it serves both as a structural molecule of the bone matrix and a signaling molecule through integrin receptors and Wnt-beta-catenin pathways whereby it stimulates osteoblast functions and bone formation. The development of periostin null mice has allowed to elucidate the crucial role of periostin on dentinogenesis and osteogenesis, as well as on the skeletal response to mechanical loading and parathyroid hormone. The use of circulating periostin as a potential clinical biomarker has been explored in different non skeletal conditions. These include cancers and more specifically in the metastasis process, respiratory diseases such as asthma, kidney failure, renal injury and cardiac infarction. In postmenopausal osteoporosis, serum levels have been shown to predict the risk of fracture-more specifically non-vertebral- independently of bone mineral density. Because of its preferential localization in cortical bone and periosteal tissue, it can be speculated that serum periostin may be a marker of cortical bone metabolism, although additional studies are clearly needed. PMID:26721738

  14. Bone metabolism during pregnancy.

    Science.gov (United States)

    Salles, Jean Pierre

    2016-06-01

    During pregnancy, mineral concentrations, of calcium and phosphorus in particular, are maintained at a high level in fetal blood so that the developing skeleton may accrete adequate mineral content. The placenta actively transports minerals for this purpose. Maternal intestinal absorption increases in order to meet the fetal demand for calcium, which is only partly dependent on calcitriol. Mineral regulation is essentially dependent on parathyroid hormone (PTH) and PTH-related protein (PTHrP). The calcium-sensing receptor (CaSR) regulates PTH and PTHrP production. If calcium intake is insufficient, the maternal skeleton will undergo resorption due to PTHrP. After birth, a switch from fetal to neonatal homeostasis occurs through increase in PTH and calcitriol, and developmental adaptation of the kidneys and intestines with bone turnover contributing additional mineral to the circulation. Calcium absorption becomes progressively active and dependent on calcitriol. The postnatal skeleton can transiently present with osteoposis but adequate mineral diet usually allows full restoration. Cases of primary osteoporosis must be identified. Loss of trabecular mineral content occurs during lactation in order to provide calcium to the newborn. This programmed bone loss is dependent on a "brain-breast-bone" circuit. The physiological bone resorption during reproduction does not normally cause fractures or persistent osteoporosis. Women who experience fracture are likely to have other causes of bone loss. PMID:27157104

  15. Inca bones at asterion

    Directory of Open Access Journals (Sweden)

    Prashant E Natekar

    2014-01-01

    Full Text Available Background: Surgical approach towards asterion has to be done with caution as many surgeons are unfamiliar with the anatomical variations. The asterion corresponds to the site of the posterolateral (mastoid fontanelle of the neonatal skull which closes at the end of the first year. Inca bones provide information as markers for various diseases, and can mislead in the diagnosis of fractures. Observation and Results: 150 dry skull bones from the Department of Anatomy at Goa Medical College, India and other neighboring medical colleges by examining the asterion, and its sutural articulations with parietal, temporal and occipital bones and also anatomical variations if any in adults. Discussion: The anatomical landmarks selected must be reliable and above all easy to identify. Bony structures are more suitable than soft tissue or cartilaginous landmarks because of their rigid and reliable location. Presence of these bones provides false impressions of fractures or the fractures may be interpreted for inca bones especially in the region of asterion either radiologically or clinically which may lead to complications during burr hole surgeries.

  16. Fibrosarcoma of bone

    International Nuclear Information System (INIS)

    A general clinical-radiological description of fibrosarcoma of bone, including tumours with features of malignant fibrous histiocytoma is presented. 104 patients with fibrosarcoma of the long bones are analysed in terms of age and sex distribution, symptoms, duration of symptoms and tumour localization. The radiological findings obtained in patients with fibrosarcoma of the long bones are discussed. The treatment and course of fibrosarcoma of the long bones are discussed. Data on the type of therapy given were available on 103 patients: 67 were treated by ablative surgery either immediately or within three months of preceding local surgery and/or radiotherapy. In the remaining 36 cases treatment consisted of local surgery, radiotherapy or a combination of these, or non-curative (palliative) treatment. In a few cases ablative surgery was performed at a later stage. 13 patients with fibrosarcoma of the axial skeleton and 14 with fibrosarcoma of the jaws are considered. A causistic discussion of patients with a secondary fibrosarcoma is presented. Secondary fibrosarcoma was found in a total of 19 patients (14%); 4 after irradiation. The features of significance for the course of the disease are discussed: general features such as age and sex, tumour localization in the long bones, presence or absence of a pathological fracture, and the radiological and histological characteristics of the tumour. The type of therapy and the occurrence of lung metastases in relation to the course of the disease is also discussed. (Auth.)

  17. Bone Regeneration Using Bone Morphogenetic Proteins and Various Biomaterial Carriers

    Directory of Open Access Journals (Sweden)

    Zeeshan Sheikh

    2015-04-01

    Full Text Available Trauma and disease frequently result in fractures or critical sized bone defects and their management at times necessitates bone grafting. The process of bone healing or regeneration involves intricate network of molecules including bone morphogenetic proteins (BMPs. BMPs belong to a larger superfamily of proteins and are very promising and intensively studied for in the enhancement of bone healing. More than 20 types of BMPs have been identified but only a subset of BMPs can induce de novo bone formation. Many research groups have shown that BMPs can induce differentiation of mesenchymal stem cells and stem cells into osteogenic cells which are capable of producing bone. This review introduces BMPs and discusses current advances in preclinical and clinical application of utilizing various biomaterial carriers for local delivery of BMPs to enhance bone regeneration.

  18. Bone printing: new frontiers in the treatment of bone defects.

    Science.gov (United States)

    Arealis, Georgios; Nikolaou, Vasileios S

    2015-12-01

    Bone defects can be congenital or acquired resulting from trauma, infection, neoplasm and failed arthroplasty. The osseous reconstruction of these defects is challenging. Unfortunately, none of the current techniques for the repair of bone defects has proven to be fully satisfactory. Bone tissue engineering (BTE) is the field of regenerative medicine (RM) that focuses on alternative treatment options for bone defects that will ideally address all the issues of the traditional techniques in treating large bone defects. However, current techniques of BTE is laborious and have their own shortcomings. More recently, 2D and 3D bone printing has been introduced to overcome most of the limitations of bone grafts and BTE. So far, results are extremely promising, setting new frontiers in the management of bone defects.

  19. Biochemical markers of bone turnover

    International Nuclear Information System (INIS)

    Biochemical markers of bone turnover has received increasing attention over the past few years, because of the need for sensitivity and specific tool in the clinical investigation of osteoporosis. Bone markers should be unique to bone, reflect changes of bone less, and should be correlated with radiocalcium kinetics, histomorphometry, or changes in bone mass. The markers also should be useful in monitoring treatment efficacy. Although no bone marker has been established to meet all these criteria, currently osteocalcin and pyridinium crosslinks are the most efficient markers to assess the level of bone turnover in the menopausal and senile osteoporosis. Recently, N-terminal telopeptide (NTX), C-terminal telopeptide (CTX) and bone specific alkaline phosphatase are considered as new valid markers of bone turnover. Recent data suggest that CTX and free deoxypyridinoline could predict the subsequent risk of hip fracture of elderly women. Treatment of postmenopausal women with estrogen, calcitonin and bisphosphonates demonstrated rapid decrease of the levels of bone markers that correlated with the long-term increase of bone mass. Factors such as circadian rhythms, diet, age, sex, bone mass and renal function affect the results of biochemical markers and should be appropriately adjusted whenever possible. Each biochemical markers of bone turnover may have its own specific advantages and limitations. Recent advances in research will provide more sensitive and specific assays

  20. Bone Targeted Therapies for Bone Metastasis in Breast Cancer

    OpenAIRE

    Wajeeha Razaq

    2013-01-01

    Cancer metastasis to the bone develops commonly in patients with various malignancies, and is a major cause of morbidity and diminished quality of life in many affected patients. Emerging treatments for metastatic bone disease have arisen from advances in our understanding of the unique cellular and molecular mechanisms that contribute to the bone metastasis. The tendency of cancer cells to metastasize to bone is probably the end result of many factors including vascular pathways, the highly ...

  1. Archival bone marrow samples

    DEFF Research Database (Denmark)

    Lund, Bendik; Najmi, Laeya A; Wesolowska-Andersen, Agata;

    2015-01-01

    AB Archival samples represent a significant potential for genetic studies, particularly in severe diseases with risk of lethal outcome, such as in cancer. In this pilot study, we aimed to evaluate the usability of archival bone marrow smears and biopsies for DNA extraction and purification, whole...... with samples stored for 4 to 10 years. Acceptable call rates for SNPs were detected for 7 of 42 archival samples. In conclusion, archival bone marrow samples are suitable for DNA extraction and multiple marker analysis, but WGA was less successful, especially when longer fragments were analyzed. Multiple SNP...

  2. FRACTURE NASAL BONES

    Directory of Open Access Journals (Sweden)

    Balasubramanian Thaigarajan

    2013-03-01

    Full Text Available Nose is the most prominent part of the face, hence it is likely to be the most common structure to be injured in the face. Although fractures involving the nasal bones are very common, it is often ignored by the patient. Patients with fractures of nasal bone will have deformity, tenderness, haemorrhage, edema, ecchymosis, instability, and crepitation. These features may be present in varying combinations. This article discusses the pathophysiology of these fractures, role of radiography and ultrasound in their diagnosis and their management.

  3. Computerized geometric features of carpal bone for bone age estimation

    Institute of Scientific and Technical Information of China (English)

    Chi-Wen Hsieh; Tai-Lang Jong; Yi-Hong Chou; Chui-Mei Tiu

    2007-01-01

    Background Bone age development is one of the significant indicators depicting the growth status of children.However, bone age assessment is an heuristic and tedious work for pediatricians. We developed a computerized bone age estimation system based on the analysis of geometric features of carpal bones.Methods The geometric features of carpals were extracted and analyzed to judge the bone age of children by computerized shape and area description. Four classifiers, linear, nearest neighbor, back-propagation neural network,and radial basis function neural network, were adopted to categorize bone age. Principal component and discriminate analyses were employed to improve assorting accuracy.Results The hand X-ray films of 465 boys and 444 girls served as our database. The features were extracted from carpal bone images, including shape, area, and sequence. The proposed normalization area ratio method was effective in bone age classification by simulation. Besides, features statistics showed similar results between the standard of the Greulich and Pyle atlas and our database.Conclusions The bone area has a higher discriminating power to judge bone age. The ossification sequence of trapezium and trapezoid bones between Taiwanese and the atlas of the GP method is quite different. These results also indicate that carpal bone assessment with classification of neural networks can be correct and practical.

  4. Vitamin D, Calcium, and Bone Health

    Science.gov (United States)

    ... Balance › Vitamin D, Calcium, and Bone Health Vitamin D, Calcium, and Bone Health March 2012 Download PDFs ... helps keep your bones strong. Why are vitamin D and calcium important to bone health? Vitamin D ...

  5. Marijuana May Blunt Bone Health

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_161575.html Marijuana May Blunt Bone Health Study finds heavy users ... 19, 2016 WEDNESDAY, Oct. 19, 2016 (HealthDay News) -- Marijuana may be bad to the bone, a new ...

  6. Bone-marrow transplant - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100112.htm Bone-marrow transplant - series To use the sharing features on ... slide 4 out of 4 Normal anatomy Overview Bone-marrow is a soft, fatty tissue found inside of ...

  7. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... little information about muscles, tendons or joints. An MRI may be more useful in identifying bone and ... bones and the spinal cord can be evaluated). MRI can also detect subtle or occult fractures or ...

  8. Vitamin A and Bone Health

    Science.gov (United States)

    ... supported by your browser. Home Bone Basics Nutrition Vitamin A and Bone Health Publication available in: PDF ( ... Find More Information? For Your Information What Is Vitamin A? Vitamin A is a family of compounds ...

  9. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... your doctor to view and assess bone fractures, injuries and joint abnormalities. This exam requires little to ... fusion, joint replacement and fracture reductions. look for injury, infection, arthritis , abnormal bone growths and bony changes ...

  10. Exercise, lifestyle, and your bones

    Science.gov (United States)

    Osteoporosis - exercise; Low bone density - exercise; Osteopenia - exercise ... your bones strong and lower your risk of osteoporosis and fractures as you get older. Before you begin an exercise program, talk with your health care provider if: ...

  11. [Pharmacology of bone anabolic agents].

    Science.gov (United States)

    Matsumoto, Toshio

    2015-10-01

    Bone is constantly remodeled to maintain its volume, structural integrity and strength Currently available bone anabolic agent is teriparatide. Teriparatide increases bone mass and strength via both remodeling-dependent and -independent mechanisms, although remodeling-dependent mechanism overweighs the other. Canonical Wnt signal plays an important role in enhancing osteoblast differentiation and bone formation, and its osteocyte-derived inhibitor, sclerostin, regulates bone formation via the regulation of Wnt signaling. Anti-sclerostin antibody stimulates Wnt signaling and enhances bone formation. Phase II clinical trials with anti-sclerostin antibodies, romosozumab and blosozumab, demonstrated a marked increase in bone mineral density after one year of treatment. The new modality of anabolic agents via remodeling-independent stimulation of bone formation may open up a new avenue for the treatment of osteoporosis.

  12. Limb Salvage After Bone Cancer

    Science.gov (United States)

    ... Blog Donate Now Select Page Limb Salvage After Bone Cancer Home > Understanding Children’s Cancer > Late Effects of Treatment > Limb Salvage After Bone Cancer Limb salvage is a surgical procedure that replaces ...

  13. Drugs Approved for Bone Cancer

    Science.gov (United States)

    ... Ask about Your Treatment Research Drugs Approved for Bone Cancer This page lists cancer drugs approved by the ... that are not listed here. Drugs Approved for Bone Cancer Abitrexate (Methotrexate) Cosmegen (Dactinomycin) Dactinomycin Denosumab Doxorubicin Hydrochloride ...

  14. Bone Anchored Hearing Treatment Procedure

    Medline Plus

    Full Text Available ... The Baha system consists of a bone-anchored titanium fixture that is implanted in the mastoid bone, ... the -- great. I'm going to grab the titanium implant. And what I want you to notice ...

  15. Cellular and Molecular Mechanisms of Bone Remodeling*

    OpenAIRE

    Raggatt, Liza J; Partridge, Nicola C

    2010-01-01

    Physiological bone remodeling is a highly coordinated process responsible for bone resorption and formation and is necessary to repair damaged bone and to maintain mineral homeostasis. In addition to the traditional bone cells (osteoclasts, osteoblasts, and osteocytes) that are necessary for bone remodeling, several immune cells have also been implicated in bone disease. This minireview discusses physiological bone remodeling, outlining the traditional bone biology dogma in light of emerging ...

  16. Cancellous structure of tarsal bones.

    OpenAIRE

    D N Sinha

    1985-01-01

    The internal structure of the tarsal bones has been studied to investigate their cancellous architecture. It is revealed that these bones have fine and coarse meshworks and even a tendency for obliteration of the trabecular pattern in the bones lying distal to this midtarsal joint. Internal structure of the talus does not show an arched pattern of bony lamellae. An increased density of bony lamellae in the internal structure of the navicular bone could result from excessive stress, enforced b...

  17. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... Resources Professions Site Index A-Z X-ray (Radiography) - Bone Bone x-ray uses a very small ... X-ray (Radiography)? What is Bone X-ray (Radiography)? An x-ray (radiograph) is a noninvasive medical ...

  18. Breast Cancer and Bone Loss

    Science.gov (United States)

    ... Balance › Breast Cancer and Bone Loss Fact Sheet Breast Cancer and Bone Loss July, 2010 Download PDFs English ... JoAnn Pinkerton, MD What is the link between breast cancer and bone loss? Certain treatments for breast cancer ...

  19. Chondrosarcoma of the hyoid bone

    Energy Technology Data Exchange (ETDEWEB)

    Demeyere, A.; Somer, F. de; Perdieus, D.; Lemmens, L.; Schillebeeckx, J. [Dept. of Radiology, Imeldaziekenhuis Bonheiden (Belgium); Hauwe, L. van den [Dept. of Radiology, University Hospital Antwerp (Belgium)

    2000-02-01

    The CT and MRI findings in a case of chondrosarcoma of the hyoid bone are reported. Although chondrosarcoma is the second most common primary malignant bone tumor, only 10 % of chondrosarcomas occur in the head and neck region. The hyoid bone is a rare site of involvement with only seven cases reported previously. (orig.)

  20. Gout: Value of bone scanning

    Energy Technology Data Exchange (ETDEWEB)

    Oliva, J.P.; Cardenas, R.; Bell, L.; Gonzalez Griego, J.

    1986-12-01

    11 male patients with gout were studied by means of bone scintigraphy with /sup 99m/TcMDP. This diagnostic method rendered possible the diagnosis of clinically or roentgenologically occult bone involvement. Bone scintigraphy may be useful procedure to monitor therapy of gout.

  1. Bone vascularization: a way to study bone microarchitecture?

    Science.gov (United States)

    Blery, P.; Autrusseau, F.; Crauste, E.; Freuchet, Erwan; Weiss, Pierre; Guédon, J.-P.; Amouriq, Y.

    2014-03-01

    Trabecular bone and its microarchitecture are of prime importance for health. Studying vascularization helps to better know the relationship between bone and vascular microarchitecture. This research is an animal study (nine Lewis rats), based on the perfusion of vascularization by a contrast agent (a mixture of 50% barium sulfate with 1.5% of gelatin) before euthanasia. The samples were studied by micro CT at a resolution of 9μm. Softwares were used to show 3D volumes of bone and vessels, to calculate bone and vessels microarchitecture parameters. This study aims to understand simultaneously the bone microarchitecture and its vascular microarchitecture.

  2. Bone metastases: When and how lung cancer interacts with bone

    OpenAIRE

    Roato, Ilaria

    2014-01-01

    Bone metastasis is a common and debilitating consequence of lung cancer: 30%-40% of patients with non-small cell lung cancer develop bone metastases during the course of their disease. Lung cancer cells find a favorable soil in the bone microenvironment due to factors released by the bone matrix, the immune system cells, and the same cancer cells. Many aspects of the cross-talk among lung tumor cells, the immune system, and bone cells are not clear, but this review aims to summarize the recen...

  3. Healthy Bones Matter

    Science.gov (United States)

    ... think that this is something that only older people need to worry about. BUT—you can take action right now to help make sure that as you get older your bones are as healthy as they can be. Eating a balanced diet ...

  4. Temporal bone imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lemmerling, Marc [Algemeen Ziekenhuis Sint-Lucas, Gent (Belgium). Dept. of Radiology; Foer, Bert de (ed.) [Sint-Augustinus Ziekenhuis, Wilrijk (Belgium). Dept. of Radiology

    2015-04-01

    Complete overview of imaging of normal and diseased temporal bone. Straightforward structure to facilitate learning. Detailed consideration of newer imaging techniques, including the hot topic of diffusion-weighted imaging. Includes a chapter on anatomy that will be of great help to the novice interpreter of imaging findings. Excellent illustrations throughout. This book provides a complete overview of imaging of normal and diseased temporal bone. After description of indications for imaging and the cross-sectional imaging anatomy of the area, subsequent chapters address the various diseases and conditions that affect the temporal bone and are likely to be encountered regularly in clinical practice. The classic imaging methods are described and discussed in detail, and individual chapters are included on newer techniques such as functional imaging and diffusion-weighted imaging. There is also a strong focus on postoperative imaging. Throughout, imaging findings are documented with the aid of numerous informative, high-quality illustrations. Temporal Bone Imaging, with its straightforward structure based essentially on topography, will prove of immense value in daily practice.

  5. Bone Marrow Matters

    Science.gov (United States)

    Dunne, Mark; Maklad, Rania; Heaney, Emma

    2014-01-01

    As a final-year student teacher specialising in primary science, Emma Heaney faced the challenge of having to plan, organise, and conduct a small-scale, classroom-based research project. She had to teach about bones in the final block practice session and thought it would be a good idea to bring in some biological specimens obtained from the local…

  6. Are Bones Alive?

    Science.gov (United States)

    Caravita, Silvia; Falchetti, Elisabetta

    2005-01-01

    Many studies have investigated the classification of living things. Our study deals with a different problem: the attribution of life to one component of a living organism, specifically the bones. The task involves not only specifying what we mean by "alive", but also requires "informed thinking" leading to an understanding of the concept of life…

  7. Bone scintigraphy in chondroblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Humphry, A.; Gilday, D.L.; Brown, R.G.

    1980-11-01

    Scintigraphy in 3 patients with chondroblastoma showed that the tumors were hyperemic and avidly accumulated the radionuclide. These changes were also present in adjacent normal bone, but to a lesser degree. This suggests that radionuclide uptake in chondroblastoma is a function of the blood supply to the tumor rather than primary matrix extraction.

  8. Chondroblastoma of temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Tanohta, K.; Noda, M.; Katoh, H.; Okazaki, A.; Sugiyama, S.; Maehara, T.; Onishi, S.; Tanida, T.

    1986-07-01

    The case of a 55-year-old female with chondroblastoma arising from the left temporal bone is presented. Although 10 cases of temporal chondroblastoma have been reported, this is the first in which plain radiography, pluridirectional tomography, computed tomography (CT) and angiography were performed. We discuss the clinical and radiological aspects of this rare tumor.

  9. Metastatic Bone Disease

    Science.gov (United States)

    ... concern for patients with MBD is the general loss in quality of life. How much of an effect MBD has on ... to be most effective in maintaining quality of life. A technetium bone scan ... blood count, because loss of red blood cells (anemia) is a frequent ...

  10. Bone island and leprosy

    International Nuclear Information System (INIS)

    Objective. To determine the incidence of bone islands in leprosy patients. Design. X-rays of feet and hands of patients with Hansen's disease (leprosy) were reviewed retrospectively. A second group of related age- and sex-matched patients who did not have Hansen's disease was used for control purposes. Controls had undergone hand or foot X-rays during diagnosis of other pathologies. The patients with Hansen's disease were compared with the control group, and were also analyzed as subgroups with different types of leprosy. The results were subjected to statistical analysis. Patients. Ninety patients with Hansen's disease were randomly selected for this study. Patients who had had ulcers on hands or feet were excluded from the study. Results and conclusions. Bone islands were demonstrated in 20 patients with Hansen's disease; no bone islands were observed in the controls. This was statistically significant (P<0.01). Bone islands were only seen in patients with lepromatous leprosy and borderline types but were not demonstrated in patients with tuberculoid leprosy. There was also a statistically significant relationship for a disease duration of 15 years or more. The cause of this raised incidence of enostosis in leprosy patients is not clear, but there may be a genetic predisposition in patients with leprosy, or it may be a side effect of leprosy, especially the lepromatous form. (orig.)

  11. Food and Your Bones

    Science.gov (United States)

    ... Store Shopping Cart Home › Patients › Treatment › Nutrition Nutrition Food For Thought Quiz True or false: Prunes contain ... health. True False View Answers Loading ... Sponsored by: Food and Your Bones – Osteoporosis Nutrition Guidelines The food ...

  12. Sodium and bone health

    DEFF Research Database (Denmark)

    Teucher, B.; Dainty, J. R.; Spinks, C. A.;

    2008-01-01

    High salt intake is a well-recognized risk factor for osteoporosis because it induces calciuria, but the effects of salt on calcium metabolism and the potential impact on bone health in postmenopausal women have not been fully characterized. This study investigated adaptive mechanisms in response...

  13. Bone scintigraphy in psoriasis

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, K.; Thiers, G.; Eissner, D.; Holzmann, H.

    1980-08-01

    Since 1973 bone scintigraphy using sup(99m)Tc-phosphate-complexes was carried out in 382 patients with psoriasis. For comparison with the results of nuclear medicine, roentgenologic and clinical findings a group af 121 patients with psoriasis aged between 11 and 74 years was compared to a group of 42 patients aged between 20 and 49 years without roentgenologic and clinical signs of psoriasis arthritis. We found by means of isotope investigation that an essentially greater part of the bones adjacent to the joints was involved than was expected according to X-ray and clinical findings. In addition, in 205 patients with psoriasis whole-body scintigraphy, using sup(99m)Tc-MDP, was carried out since 1977/78. In 17 patients we found an increased accumulation of activity in the region of extraarticular structures of the skull as well as of the skeletal thorax. According to these results we conclude that in addition to the clinically and roentgenologically defined psoriatic arthritis in patients with psoriasis an osteopathy may exist, which can only be demonstrated by skeletal scintigraphy and which is localized in bones adjacent to the joints but can also be demonstrated in the region of extraarticular bones.

  14. [Metabolic bone disease osteomalacia].

    Science.gov (United States)

    Reuss-Borst, M A

    2014-05-01

    Osteomalacia is a rare disorder of bone metabolism leading to reduced bone mineralization. Underlying vitamin D deficiency and a disturbed phosphate metabolism (so-called hypophosphatemic osteomalacia) can cause the disease. Leading symptoms are dull localized or generalized bone pain, muscle weakness and cramps as well as increased incidence of falls. Rheumatic diseases, such as polymyalgia rheumatica, rheumatoid arthritis, myositis and fibromyalgia must be considered in the differential diagnosis. Alkaline phosphatase (AP) is typically elevated in osteomalacia while serum phosphate and/or 25-OH vitamin D3 levels are reduced. The diagnosis of osteomalacia can be confirmed by an iliac crest bone biopsy. Histological correlate is reduced or deficient mineralization of the newly synthesized extracellular matrix. Treatment strategies comprise supplementation of vitamin D and calcium and for patients with intestinal malabsorption syndromes vitamin D and calcium are also given parenterally. In renal phosphate wasting syndromes substitution of phosphate is the treatment of choice, except for tumor-induced osteomalacia when removal of the tumor leads to a cure in most cases. PMID:24811356

  15. Super bone scans on bone scintigraphy in patients with metastatic bone tumor

    International Nuclear Information System (INIS)

    Eight patients with malignant tumor (3 with gastric cancer, 4 with prostatic cancer, 1 with transitional cell carcinoma), which showed diffusely increased uptake of 99mTc labelled phosphorous compound in axial skeleton (''Super Bone Scan'') on bone scintigraphy were clinically studied. No relationship with its histological type of the tumor was recognized. All cases revealed extremely high serum ALP concentration, which might reflect increased osteoblastic activity. Furthermore, on bone roentgenograms all cases showed predominantly osteosclerotic change in the metastatic bones, while some did locally osteolytic change. In three cases with gastric cancer, although they had diffuse skeletal metastases, two had no evidence of liver metastases. Thus, it seemed that clinical study of patients with ''Super Bone Scan'' was interesting to evaluate the mechanism of accumulation of 99mTc labelled phosphorous compound to bone and bone metabolism, and the pathophysiology in the pathway of bone metastases. (author)

  16. Combined bone grafting: an alternative method for bone healing stimulation

    International Nuclear Information System (INIS)

    The most provocative problem in bone grafting is the effectiveness of healing of the graft. When you use the heterogenous bone graft, it may take one or more than two years for consolidation and union depends on the graft quality and the situation of surrounding blood supply. In our preliminary report seven cases of freeze-dried heterogenous bone graft from the Bangkok Biomaterial Center were mixed with autogenous iliac bone graft from the patient in the ratio of 3:1. After that the healing was checked by clinical examination and X-ray in the periodic follow up. The causes of bone lost are post evacuation of benign bone tumor and post infection of bone after trauma. The result of bony union could be tested by clinical examination and showed in the X-ray films as early as 3 months post grafting

  17. Bone marrow oedema associated with benign and malignant bone tumours

    Energy Technology Data Exchange (ETDEWEB)

    James, S.L.J. [Department of Radiology, Royal Orthopaedic Hospital, Birmingham, B31 2AP (United Kingdom)], E-mail: steven.james@roh.nhs.uk; Panicek, D.M. [Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021 (United States); Davies, A.M. [Department of Radiology, Royal Orthopaedic Hospital, Birmingham, B31 2AP (United Kingdom)

    2008-07-15

    Bone marrow oedema is associated with a wide variety of pathological processes including both benign and malignant bone tumours. This imaging finding in relation to intraosseous tumours can aid in providing a more focused differential diagnosis. In this review, we will discuss the MR imaging of bone marrow oedema surrounding intraosseous neoplasms. The different pulse sequences used in differentiating underlying tumour from surrounding oedema are discussed along with the role of dynamic contrast enhanced MRI. Benign lesions commonly associated with bone marrow oedema include osteoid osteoma, osteoblastoma, chondroblastoma and Langerhan's cell histiocytosis. Metastases and malignant primary bone tumours such as osteosarcoma, Ewing's sarcoma and chondrosarcoma may also be surrounded by bone marrow oedema. The imaging findings of these conditions are reviewed and illustrated. Finally, the importance of bone marrow oedema in assessment of post chemotherapeutic response is addressed.

  18. Curative effect of bone transport for infectious large segmental bone defect after surgical treatment for tibial fracture%骨搬移术治疗胫骨骨折术后感染性大段骨缺损的疗效分析

    Institute of Scientific and Technical Information of China (English)

    郝光亮; 张贵春; 曹学成

    2014-01-01

    背景:胫骨骨折术后感染性大段骨缺损的发生率高,治疗困难,效果不理想。目前,骨缺损修复方法包括皮瓣覆盖+自体骨移植术、异体骨或异种骨移植、带血供腓骨移植、骨延长和骨搬移术。  目的:探讨骨搬移术治疗胫骨骨折术后感染性大段骨缺损的疗效。  方法:选取2010年9月至2014年9月收治的胫骨骨折术后感染性大段骨缺损患者40例,男24例,女16例;年龄18~64岁,平均(42.8±12.1)岁。将患者随机分成两组各20例,一组采用Orthofix单臂外固定延长架截骨延长,另一组采用Ilizarov环形外固定延长架截骨延长,术后随访对比两组患者的手术时间、手术出血量、HHS膝关节功能评分、Baird-Jackson踝关节功能评分。  结果:Orthofix单臂外固定延长架的手术时间较短、手术出血量较少,与Ilizarov环形外固定延长架比较均有统计学差异(P<0.05)。两组患者的术后HHS膝关节功能评分、Baird-Jackson踝关节功能评分均较术前有明显提高(P<0.01)。  结论:骨搬移术治疗胫骨骨折术后感染性大段骨缺损的疗效佳,可较好地改善患者的膝关节和踝关节功能。其中Or-thofix单臂外固定延长架能减少手术创伤,安全性较高,但骨搬运过程中容易发生延长骨成角和偏移;Ilizarov环形外固定延长架的术中应用置入较多钢针,移动时可造成部分皮瓣坏死和血管损伤,应避免在皮瓣覆盖创面的胫骨大段骨缺损患者中使用。%Background:There are high incidences of infectious large segmental bone defect after surgical treatment for tibial fracture, and it is very difficult to be cured. At present, there are a few of methods for repairing bone defect, such as skin flap cover-age plus autogenous bone transplantation, allograft bone or xenogeneic bone transplantation, vascularized fibular graft, bone lengthening and bone

  19. 根面成形术在牙冠延长手术中的应用%Application of root angioplasty in crown lengthening surgery

    Institute of Scientific and Technical Information of China (English)

    刘丽静; 张雷; 龚连喜

    2016-01-01

    Objective To analyze the application of root angioplasty in the crown lengthening surgery. Methods A total of 80 patients that corresponding to criteria from January 2013 to December 2015 in repair outpatients of our hospital were selected and received retrospec-tive study,and they were randomly divided into the observation group and the control group according to different surgical methods with 40 ca-ses in each group. The observation group was given root angioplasty and crown lengthening surgery,while the control group was only given crown lengthening surgery. Check-up was performed at 6 weeks postoperatively and 3 weeks after restoration,the condition of root surface cov-ered by the gum,the condition of gingival recession of the restoration and the subjective satisfaction of the patients were observed. Results The average coverage of the observation group was 91. 3%,which was significantly more than 55. 3% of the control group (P<0. 05). The a-mount of the gum covering of the observation group was (3.1 ±1.3)mm,which was significantly larger than (1.9 ±1.0)mm of the control group(P<0. 05). Conclusion Root angioplasty can guarantee blood supply,reduce the damage,but the indication range is small,and it is influenced by many factors,and needs to incorporate the ideas of all sides when used in clinic.%目的:探讨根面成形术在牙冠延长手术中的应用效果。方法选择2013年1月至2015年12月在我院修复科就诊的符合要求的患者80例,根据手术方法的不同分成观察组和对照组,每组40例。观察组采用根面成形术和常规牙冠延长术,对照组仅行常规牙冠延长术。分别在术后第6周和修复后第3周进行复查,观察牙龈覆盖根面的情况,修复体边缘有无牙龈退缩和患者主观满意度。结果观察组平均覆盖率为91.3%,对照组平均覆盖率为55.3%,2组比较差异有统计学意义(P<0.05);观察组牙龈覆盖量为(3.1±1.3)mm,对照组牙龈覆盖量为(1.9±1.0)mm,2

  20. A curative observation of surgical crown lengthening in split teeth restoration%牙冠延长术修复劈裂牙的疗效观察

    Institute of Scientific and Technical Information of China (English)

    高慧英

    2015-01-01

    Objective: To explore the clinical effect of surgical crown lengthening on restoration of broken teeth.Methods: Sixty-eight broken teeth in 62 patients were selected, and were randomly divided into group A and B, 31 patients per group, 36 broken teeth in group A and 32 broken teeth in group B. Patients in group A were given gingivectomy, and patients in group B were given crown lengthening surgery. Broken end and gingival margin of broken teeth before and after surgery were compared, including plaque index (PLI), sulcus bleeding in-dex (SBI), periodontal probing depth (PD), gomphiasis and repair effect.Results: All patients were successfully performed surgery according to plan, periodontal index after surgery were improved (P0.05). After operation, teeth mobility rate in group A was 25.00%, yet there was no tooth mobility in group B, and group A’s teeth mobility rate was higher than that in group B (P<0.05). Two groups’ effective rate of teeth restoration were both 100%, and satisfaction rate were 63.89% and 81.25% respectively in group A and group B.Conclusion: It has good effect of broken teeth restoration by crown lengthening surgery, the procedure can improve and maintain a healthy repaired result. If the indication right, can control the periodontal inlfammation.%目的:探讨牙冠延长术在劈裂牙修复中的临床应用效果。方法:选取62例患者共68颗劈裂牙,随机将其分为A、B2组各31例,A组劈裂牙36颗,B组劈裂牙32颗。A组予以牙龈切除术,B组予以牙冠延长术。比较2组术前及术后多时点患牙断端与龈缘情况,包括菌斑指数(PLI)、龈沟出血指数(SBI)、牙周探诊深度(PD)、牙齿松动度及修复效果等。结果:2组均按既定方案顺利完成手术,术后各时间点牙周指数均较术前改善,差异有统计学意义(均P<0.05),但2组间各时间点牙周指数相互比较,差异均无统计学意义(均P>0.05)

  1. Function of osteocytes in bone.

    Science.gov (United States)

    Aarden, E M; Burger, E H; Nijweide, P J

    1994-07-01

    Although the structural design of cellular bone (i.e., bone containing osteocytes that are regularly spaced throughout the bone matrix) dates back to the first occurrence of bone as a tissue in evolution, and although osteocytes represent the most abundant cell type of bone, we know as yet little about the role of the osteocyte in bone metabolism. Osteocytes descend from osteoblasts. They are formed by the incorporation of osteoblasts into the bone matrix. Osteocytes remain in contact with each other and with cells on the bone surface via gap junction-coupled cell processes passing through the matrix via small channels, the canaliculi, that connect the cell body-containing lacunae with each other and with the outside world. During differentiation from osteoblasts to mature osteocyte the cells lose a large part of their cell organelles. Their cell processes are packed with microfilaments. In this review we discuss the various theories on osteocyte function that have taken in consideration these special features of osteocytes. These are 1) osteocytes are actively involved in bone turnover; 2) the osteocyte network is through its large cell-matrix contact surface involved in ion exchange; and 3) osteocytes are the mechanosensory cells of bone and play a pivotal role in functional adaptation of bone. In our opinion, especially the last theory offers an exciting concept for which some biomechanical, biochemical, and cell biological evidence is already available and which fully warrants further investigations.

  2. Influence of bone environment on ceramic osteointegration in spinal fusion: comparison of bone-poor and bone-rich sites

    OpenAIRE

    Delécrin, Joël; Deschamps, Cédric; Romih, Mostafa; Heymann, Dominique; Passuti, Norbert

    2001-01-01

    Quantitative experimental data showed differences in bone quality and ceramic incorporation between bone-rich and bone-poor implantation sites. Bone in-growth was significantly lower for ceramic implanted at a lumbar intertransverse than a laminar site. Bone-marrow enrichment of the lumbar intertransverse site (regarded as bone-poor) greatly facilitated ceramic osteointegration. The vertebral interbody site, despite theoretical richness in osteogenic precursor cells, might be bone-poor at the...

  3. Bone- and bone marrow scintigraphy in Gaucher disease type 1

    Energy Technology Data Exchange (ETDEWEB)

    Mikosch, P. [Dept. of Nuclear Medicine and Endocrinology, State Hospital Klagenfurt (Austria); Dept. of Internal Medicine II, State Hospital Klagenfurt (Austria); Zitter, F. [Dept. of Internal Medicine II, State Hospital Klagenfurt (Austria); Gallowitsch, H.J.; Lind, P. [Dept. of Nuclear Medicine and Endocrinology, State Hospital Klagenfurt (Austria); Wuertz, F. [Dept. of Pathology, State Hospital Klagenfurt (Austria); Mehta, A.B.; Hughes, D.A. [Lysosomal Storage Disorder Unit, Dept. of Academic Haematology, Royal Free and Univ. Coll. Medical School, London (United Kingdom)

    2008-07-01

    Scintigraphy is a method for imaging metabolism and should be viewed as complimentary to morphological imaging. Bone and bone marrow scintigraphy can particularly contribute to the detection of focal disease in Gaucher disease. In bone crises it can discriminate within three days after pain onset between local infection and aseptic necrosis. A further advantage of bone- and bone marrow scintigraphy is the visualization of the whole skeleton within one setting. Whole body imaging for focal lesions might thus be an objective in GD, in particular in patients complaining of several painful sites. Direct imaging of bone marrow deposits in GD by MIBI scintigraphy might be of special interest in children in whom bone marrow undergoes a developmental conversion from red to yellow marrow in the ap-pendicular skeleton. MRI interpretation in young GD patients is thus difficult in order to estimate the exact amount and extent of bone marrow infiltration by Gaucher cells. 99mTc-MIBI scintigraphy with its direct visualization of lipid storage could thus add interesting additional information not shown with other methods including MRI. Although MRI is the most accepted imaging modality in assessing the skeletal status in GD, a selective use of scintigraphy for imaging bone and bone marrow may add information in the evaluation of patients with Gaucher disease.

  4. Temporal Bone Localized Chondroblastoma.

    Science.gov (United States)

    Demirhan, Hasan; Acioğlu, Engin; Durna, Yusuf Muhammed; Yiğit, Özgür; Bozkurt, Erol Rüştü; Karagöz, Yeşim

    2015-11-01

    Chondroblastoma is a highly destructive tumor originating from immature cartilage cells. Although chondroblastoma is defined as a benign tumor, it may exhibit malign tumor behaviors such as invasion or metastasis on neighboring structures. Magnetic resonance (MR) image is a solid mass lesion, which included heterogeneous hypointense in T2A and heterogeneous minimal hyperintense in T1A with destructive expansile characteristics and millimetric calcifications. Temporal bone chondroblastomas may complicate the diagnosis because of their different histologic characteristics. Microscopically, chondroblastic cell nests and calcification of locally "chicken wire" type around the cells are observed. These tumors secrete s-100 and vimentin and are used for differential diagnosis. In this study, a temporal bone localized chondroblastoma case is presented. PMID:26517458

  5. Temporal Bone Localized Chondroblastoma.

    Science.gov (United States)

    Demirhan, Hasan; Acioğlu, Engin; Durna, Yusuf Muhammed; Yiğit, Özgür; Bozkurt, Erol Rüştü; Karagöz, Yeşim

    2015-11-01

    Chondroblastoma is a highly destructive tumor originating from immature cartilage cells. Although chondroblastoma is defined as a benign tumor, it may exhibit malign tumor behaviors such as invasion or metastasis on neighboring structures. Magnetic resonance (MR) image is a solid mass lesion, which included heterogeneous hypointense in T2A and heterogeneous minimal hyperintense in T1A with destructive expansile characteristics and millimetric calcifications. Temporal bone chondroblastomas may complicate the diagnosis because of their different histologic characteristics. Microscopically, chondroblastic cell nests and calcification of locally "chicken wire" type around the cells are observed. These tumors secrete s-100 and vimentin and are used for differential diagnosis. In this study, a temporal bone localized chondroblastoma case is presented.

  6. [Fractures of carpal bones].

    Science.gov (United States)

    Lögters, T; Windolf, J

    2016-10-01

    Fractures of the carpal bones are uncommon. On standard radiographs fractures are often not recognized and a computed tomography (CT) scan is the diagnostic method of choice. The aim of treatment is to restore pain-free and full functioning of the hand. A distinction is made between stable and unstable carpal fractures. Stable non-displaced fractures can be treated conservatively. Unstable and displaced fractures have an increased risk of arthritis and non-union and should be stabilized by screws or k‑wires. If treated adequately, fractures of the carpal bones have a good prognosis. Unstable and dislocated fractures have an increased risk for non-union. The subsequent development of carpal collapse with arthrosis is a severe consequence of non-union, which has a heterogeneous prognosis.

  7. Dynamic scintigraphy of bone and bone marrow in multiple myeloma patients with bone-marrow transplants

    International Nuclear Information System (INIS)

    Purpose: To determine whether dynamic registration at bone and bone-marrow scintigraphy produces additional information compared to subsequent static registrations of bone-marrow transplants in multiple myeloma patients. Material and Methods: In a prospective study, 8 dynamic bone and 6 dynamic bone-marrow scintigraphies were performed in 10 patients. The dynamic scintigraphies were compared with conventional radiography, MR images, and static scintigraphies of bone and bone marrow. Results: No additional information was revealed by the dynamic registration method; on the contrary, 4 of the 8 known lesions were not discerned at dynamic registration. An incidental observation was that the time-activity curves of both radiopharmaceuticals had a specific pattern. (orig.)

  8. Shang Oracle Bones

    Science.gov (United States)

    Pankenier, David W.

    Astronomical observations first appear in China's archaeological record on turtle plastrons and ox scapulae from the reigns of the last few kings of the Shang Dynasty (1250-1046 BCE). A variety of meteorological and astronomical phenomena were divined about and recorded by scribes in formulaic language that is recognizably archaic Chinese. The oracle bone inscriptions record sacrifices to celestial bodies and the proper ritual response to anomalous phenomena like eclipses.

  9. [Primary liposarcoma of bone].

    Science.gov (United States)

    Tatić, V; Cerović, S; Skaro-Milić, A; Jovanović, Z

    2001-01-01

    A case of 75-year-old man with extremely rare primary liposarcoma of the bone was presented. Stains for lipid, Sudan III, Sudan IV, and Oil Red "O", demonstrated the presence of intracellular lipid in the lipoblasts. Similarly, the S-100 immunoreactivity and electron microscopic findings of tumor cells confirmed the diagnosis of liposarcoma. Histochemical stains for PAS, Alcian-blue, mucikarmin, Toluidin-blue and Coloidal Iron were negative. PMID:11419292

  10. Bone tissue engineering

    OpenAIRE

    Black, Cameron R. M.; Goriainov, Vitali; Gibbs, David; Kanczler, Janos; Tare, Rahul S; Richard O. C. Oreffo

    2015-01-01

    Medical advances have led to a welcome increase in life expectancy. However, accompanying longevity introduces new challenges: increases in age-related diseases and associated reductions in quality of life. The loss of skeletal tissue that can accompany trauma, injury, disease or advancing years can result in significant morbidity and significant socio-economic cost and emphasise the need for new, more reliable skeletal regeneration strategies. To address the unmet need for bone augmentation,...

  11. Bone Metabolism on ISS Missions

    Science.gov (United States)

    Smith, S. M.; Heer, M. A.; Shackelford, L. C.; Zwart, S. R.

    2014-01-01

    Spaceflight-induced bone loss is associated with increased bone resorption (1, 2), and either unchanged or decreased rates of bone formation. Resistive exercise had been proposed as a countermeasure, and data from bed rest supported this concept (3). An interim resistive exercise device (iRED) was flown for early ISS crews. Unfortunately, the iRED provided no greater bone protection than on missions where only aerobic and muscular endurance exercises were available (4, 5). In 2008, the Advanced Resistive Exercise Device (ARED), a more robust device with much greater resistance capability, (6, 7) was launched to the ISS. Astronauts who had access to ARED, coupled with adequate energy intake and vitamin D status, returned from ISS missions with bone mineral densities virtually unchanged from preflight (7). Bone biochemical markers showed that while the resistive exercise and adequate energy consumption did not mitigate the increased bone resorption, bone formation was increased (7, 8). The typical drop in circulating parathyroid hormone did not occur in ARED crewmembers. In 2014, an updated look at the densitometry data was published. This study confirmed the initial findings with a much larger set of data. In 42 astronauts (33 male, 9 female), the bone mineral density response to flight was the same for men and women (9), and those with access to the ARED did not have the typical decrease in bone mineral density that was observed in early ISS crewmembers with access to the iRED (Figure 1) (7). Biochemical markers of bone formation and resorption responded similarly in men and women. These data are encouraging, and represent the first in-flight evidence in the history of human space flight that diet and exercise can maintain bone mineral density on long-duration missions. However, the maintenance of bone mineral density through bone remodeling, that is, increases in both resorption and formation, may yield a bone with strength characteristics different from those

  12. Battling Brittle Bones

    Science.gov (United States)

    2002-01-01

    The accuDEXA(R) Bone Mineral Density Assessment System, manufactured by Schick Technologies, Inc., utilizes "camera on a chip" sensor technology invented and developed by NASA's Jet Propulsion Laboratory. Schick's accuDEXA system offers several advantages over traditional osteoporosis tests, which assess bone density loss in the hip and spine, and require specialized personnel to conduct. With accuDEXA, physicians can test the entire body's bone density at a peripheral site, such as the finger, without applying gels or having patients remove garments. Results are achieved in 30 seconds and printed out in less than a minute, compared to the estimated exam time of 15 minutes for hip and spine density analyses. Schick has also applied the CMOS APS technology to a new software product that performs dental radiography using up to 90 percent less radiation exposure than conventional X-rays. Called Computed Dental Radiography(R), the new digital imaging product utilizes an electronic sensor in place of X-ray film to generate sharp and clear images that appear on a computer screen within 3 seconds, and can be enlarged and enhanced to identify problems.

  13. Virtual temporal bone

    Institute of Scientific and Technical Information of China (English)

    QIU Ming-guo; ZHANG Shao-xiang; LIU Zheng-jin; TAN Li-wen; WANG Yu-su; DENG Jun-hui; TANG Ze-sheng

    2002-01-01

    Objective:To provide the virtual model of the temporal bone for improving 3-dimension (3D) visualization of the inner ear. Methods: Plastination technique was used to make equidistant serial thin sections 1.0 mm in thickness. On SGI workstation, a Contours+Marching Cubes algorithm was selected to reconstruct the temporal bone and intratemporal structures in 3D, then to view the middle ear, inner ear, and intratemporal structures which imitate the scenes observed by the traditional endoscopy. Results: The virtual model of the temporal bone was successfully constructed, with all reconstructed structures being represented individually or jointly and being rotated continuously in any plane. Virtual endoscopy improved 3D visualization of the middle ear, inner ear, and intratemporal structures. Conclusion: The reconstructed model can be used for the medical students to rehearse or review the surgeries on this part and for the surgeons to develop a new approach for operation. Virtual otoscopy stands as a promising new visualization technique for elucidating the structure and relation of the middle ear, inner ear, and intratemporal structures.

  14. Bone Metabolism in Adolescents with Anorexia Nervosa

    OpenAIRE

    Misra, Madhusmita; Klibanski, Anne

    2011-01-01

    Adolescents with anorexia nervosa (AN) are at risk for low bone mass at multiple sites, associated with decreased bone turnover. Bone microarchitecture is also affected, with a decrease in bone trabecular volume and trabecular thickness, and an increase in trabecular separation. The adolescent years are typically the time when marked increases occur in bone mass accrual towards the attainment of peak bone mass, an important determinant of bone health and fracture risk in later life. AN often ...

  15. 激光辅助的非翻瓣冠延长术:病例研究%Laser-Assisted Flapless Crown Lengthening: A Case Series

    Institute of Scientific and Technical Information of China (English)

    Michael K.McGuire; E.Todd Scheyer; 李熠

    2012-01-01

    由于现阶段对手术操作的要求趋向于微创,越来越多的关于非翻瓣而采用激光辅助冠延长术(Lasermediated Flapless Crown Lengthening)的文章出现在各种期刊中.但是,大多数的文章都是病例报告或者是操作技术方面的探讨.关于科学地评价激光冠延长术(非翻瓣)的安全性和有效性的前瞻性、随机和对照研究却很少.本文对于微创不翻瓣手术所产生的临床问题进行了初步分析和研究.事实上,只有严格设计、随机、对照的试验才可以为循证医学提供数据,才可将非翻瓣的冠延长术归为标准冠延长术的治疗方法中.

  16. The clinical effect of minimally invasive crown lengthening%微创牙冠延长术的临床疗效评价

    Institute of Scientific and Technical Information of China (English)

    汪涌; 陈莹; 姚莉莉

    2016-01-01

    Objective:The goal of this investigation was to evaluate the clinical effect of minimally inva-sive technique in crown lengthening.Method:Thirty-nine patients with 45 teeth defects 1.5-4 mm below gingiva were randomly divided into two groups.The crowns were lengthened with traditional method in control groud(22 patients with 24 teeth),and experimental group(17 patients with 21 teeth) used minimally invasive technique:surgery was performed with the aid of an operating microscope and microsurgical instrument, the crown were lengthened with piezosurgery,5-0 stitches in suture.Probing depth( PD) ,sulcus bleeding index( SBI) and mobili-ty degree( MD) were measured before surgery and one week,8 weeks after surgery,and 6 months after prosthodon-tic.Gingival recession( GR) was measured at 6 months after prosthodontic treatment,and recorded the postopera-tive adverse reactions.Results:SBI,PD at one week after surgery in two groups were obviously improved which compared with presurgical(P0.05) .At 1 week after surgery experimental group the SBI and PD is better than that of control group,the differences between two groups was statistically significant(P<0.01).At 8 weeks postsurgery and 6 months after prosthodontic treatment PD in experimental group is lower than control group(P<0.01),the improvement of SBI is superior to the control group(P<0.05).GR was observed in 6 teeth of control group 6 month after prosthodontic,and there are 4 cases with postoperative swelling and 3 cases with postoperative pain in control group,but not observed in experimental group(P<0.05)Conclusion:Minimally invasive technol-ogy in crowns lengthening can obviously improve the clinical indicators, reduce postoperative adverse reactions and gingival recession.%目的:评价微创技术应用于牙冠延长术的临床效果。方法:将39例患者的45颗冠缺损达龈下最深位点1.5~4 mm患牙进行随机分组。对照组24颗患牙施行常规牙冠延长术;实验组21颗患牙是

  17. 阴茎延长术的解剖与临床应用%Anatomy and Clinical Application of Penis Lengthening Surgery

    Institute of Scientific and Technical Information of China (English)

    马全福; 吴学杰; 袁延年; 李宗来; 丁自海; 陈文军

    2011-01-01

    Objective To explore the feasibility and safety of penis lengthening surgery in adult. Methods Based on our measurements of prolonged penile length and anotomy of penile vein in 20 adult corpora, we performed penis lengthening surgery on 46 men with short penis [(2.8±1.2) cm, ranged 1.6-3.5 cm]. A N-shape incision with the left-to-right width 3. 0 - 4. 5 cm was made at the end of the penis. We preserved a thick enough skin flap with sufficient blood supply, and the thickness between the skin to the fundiform ligament 3.0 - 5.0 cm. Under direct vision, or by exploring with fingers, we cut the fundiform ligament and 1/3 of the suspensory ligament, and then left a drainage rubber at the incision. Results In the 20 adult corpora, the mean thickness of the fundiform ligament at the proximal end of the penis was (0.4 ±0. 1) cm (0.2 -0.7 cm) , and the width was (3. 1 ±0.9) cm (2.1 -5.0 cm) , while those of the suspensory ligament were (2. 5 ± 1.0) cm (2.0 -3. 1 cm) and (0.5 ±0. 1) cm (0. 4 - 0. 6 cm) , respectively. In the 46 patients, the length of the penis at resting was (4.6±1.5) cm (3.5-6. 0 cm) after the operation, which was significantly lengthened by (2. 5 ± 0. 7 ) cm (1.9-3.5 cm ) compared to pre-operation ( t = 4. 228, P = 0. 000). Three patients developed hydrophallus after the procedure, and then was cured by bathing with 1: 5000 furacilinum for three months. Follow-up was achieved in 42 patients (91.3% ) for 8 months to 15 years with a mean of 6 years and 2 months, 31 of then had been followed up for over 5 years; 36 (85. 7% ) of the patients were satisfied with sexual life and had their confidence improved, the other 6 patients (14.3%) were still not satisfied with the length of their penis. Conclusions Penis lengthening surgery is safe and effective by resecting the fundiform ligament and part of the suspensory ligament. Postoperative subcutaneous intractable edema of the penis is related to the injuries to the superficial dorsal vein and lymphatic

  18. Surgical reconstruction of posterior tibial tendon dysfunction: prospective comparison of flexor digitorum longus substitution combined with lateral column lengthening or medial displacement calcaneal osteotomy.

    Science.gov (United States)

    Marks, Richard M; Long, Jason T; Ness, Mary Ellen; Khazzam, Michael; Harris, Gerald F

    2009-01-01

    Posterior tibial tendon dysfunction (PTTD) may require surgical intervention when nonoperative measures fail. Different methods of bony reconstruction may supplement tendon substitution. This study compares two types of bony procedures used to reinforce reconstruction of the posterior tibial tendon-the lateral column lengthening (LCL), and the medial displacement calcaneal osteotomy (MDCO). Twenty patients with PTTD were evaluated before and after scheduled reconstruction comprised of either flexor digitorum longus (FDL) substitution combined with MDCO (MDCO group, 14 patients) or FDL substitution with LCL fusion or osteotomy (LCL group, 6 patients). Foot/ankle kinematics and temporal-spatial parameters were analyzed using the Milwaukee Foot Model, and results were compared to a previously evaluated normal population of 25 patients. Post-operatively, both patient groups demonstrated significantly improved stride length, cadence and walking speed, as well as improved hindfoot and forefoot position in the sagittal plane. The LCL group also demonstrated greater heel inversion. All post-operative subjects revealed significant improvement in the talo-MT1 angle in the A/P and lateral planes, calcaneal pitch and medial cuneiform-MT5 height. Surgical reconstruction of PTTD with either the LCL or MDCO shows comparable improvements in gait parameters, with better heel inversion seen with the LCL, but improved 1st ray plantarflexion and varus with the MDCO. Both procedures demonstrated comparable improvements in radiographic measurements. PMID:18603429

  19. 应用外固定延长技术治疗虎口挛缩%Treatment of first web space contracture using lengthening technique with external fixator

    Institute of Scientific and Technical Information of China (English)

    陈山林; 易传军; 田光磊; 田文; 郜永斌; 王树锋; 朱瑾; 郭阳

    2008-01-01

    Objective To investigate the operative technique and clinical outcome of using lengthening technique with Orthofix minifixator system to keep the thumb in the desired position after simultaneous soft-tissue release for treatment of first web space. Methods Fifty-six cases diagnosed as first web space contracture were treated with the lengthening technique with external fixation from August 2002 to October 2006.Fortv patients were followed up in detail.There were 35 males and 5 females,with average age of 34 years (range 18-52 years).Twenty-six cases occurred in right hand,fourteen cases in left hand.The defect was caused by trauma in 30 patients,by burn in 10 patients.According to the classification criterion established by Gu (1986),moderate contracture occurred in twenty-five cases,severe contracture in fifteen cases.After surgical release of the contracture,Orthofix minifixator(type B-46)pins were inserted into the first and second metacarpals at the level of nearby the first and second metacarpal neck.The external fixator served as a tool for gradual correction and to secure ioint position after soft-tissue release.Lengthening progress started at the first day after operation with a speed of 1 mm/day until the maximal thumb abduction was obtained.The fixators were removed after six to eight weeks.The breadth of the thumb web space was mensured and recorded at the last time of follow up.Results Forty cases of the patients were followed up for 3-6 months with average 4 months.All patients experienced increased activity and improvement in grasping obiects at follow-up evaluations.The thumb was in an average of 20 degrees of palmar abduction.The distance between the radial side of metacarpal phalangeal joint of the index finger and the ulnar side of interphalangeal joint of the thumb was enhanced to 2.5 cm.Pin site infection happened in five patients.Semidislocation of the first carpometacarpal ioint occurred in four patients.Ulnar inclination deformity of the

  20. Modulation of Telomeres in Alternative Lengthening of Telomeres Type I Like Human Cells by the Expression of Werner Protein and Telomerase

    Directory of Open Access Journals (Sweden)

    Aisha Siddiqa

    2012-01-01

    Full Text Available The alternative lengthening of telomeres (ALT is a recombination-based mechanism of telomere maintenance activated in 5–20% of human cancers. In Saccharomyces cerevisiae, survivors that arise after inactivation of telomerase can be classified as type I or type II ALT. In type I, telomeres have a tandem array structure, with each subunit consisting of a subtelomeric Y′ element and short telomere sequence. Telomeres in type II have only long telomere repeats and require Sgs1, the S. cerevisiae RecQ family helicase. We previously described the first human ALT cell line, AG11395, that has a telomere structure similar to type I ALT yeast cells. This cell line lacks the activity of the Werner syndrome protein, a human RecQ helicase. The telomeres in this cell line consist of tandem repeats containing SV40 DNA, including the origin of replication, and telomere sequence. We investigated the role of the SV40 origin of replication and the effects of Werner protein and telomerase on telomere structure and maintenance in AG11395 cells. We report that the expression of Werner protein facilitates the transition in human cells of ALT type I like telomeres to type II like telomeres in some aspects. These findings have implications for the diagnosis and treatment of cancer.

  1. Analysis of neural progenitors from embryogenesis to juvenile adult in Xenopus laevis reveals biphasic neurogenesis and continuous lengthening of the cell cycle

    Directory of Open Access Journals (Sweden)

    Raphaël Thuret

    2015-12-01

    Full Text Available Xenopus laevis is a prominent model system for studying neural development, but our understanding of the long-term temporal dynamics of neurogenesis remains incomplete. Here, we present the first continuous description of neurogenesis in X. laevis, covering the entire period of development from the specification of neural ectoderm during gastrulation to juvenile frog. We have used molecular markers to identify progenitors and neurons, short-term bromodeoxyuridine (BrdU incorporation to map the generation of newborn neurons and dual pulse S-phase labelling to characterise changes in their cell cycle length. Our study revealed the persistence of Sox3-positive progenitor cells from the earliest stages of neural development through to the juvenile adult. Two periods of intense neuronal generation were observed, confirming the existence of primary and secondary waves of neurogenesis, punctuated by a period of quiescence before metamorphosis and culminating in another period of quiescence in the young adult. Analysis of multiple parameters indicates that neural progenitors alternate between global phases of differentiation and amplification and that, regardless of their behaviour, their cell cycle lengthens monotonically during development, at least at the population level.

  2. Bone morphogenetic proteins: Periodontal regeneration

    Directory of Open Access Journals (Sweden)

    Subramaniam M Rao

    2013-01-01

    Full Text Available Periodontitis is an infectious inflammatory disease that results in attachment loss and bone loss. Regeneration of the periodontal tissues entails de novo formation of cementum, periodontal ligament, and alveolar bone. Several different approaches are currently being explored to achieve complete, reliable, and reproducible regeneration of periodontal tissues. The therapeutic management of new bone formation is one of the key issues in successful periodontal regeneration. Bone morphogenetic proteins form a unique group of proteins within the transforming growth factor superfamily of genes and have a vital role in the regulation in the bone induction and maintenance. The activity of bone morphogenetic proteins was first identified in the 1960s, but the proteins responsible for bone induction were unknown until the purification and cloning of human bone morphogenetic proteins in the 1980s, because of their osteoinductive potential. Bone morphogenetic proteins have gained a lot of interest as therapeutic agents for treating periodontal defects. A systematic search for data related to the use of bone morphogenetic proteins for the regeneration of periodontal defects was performed to recognize studies on animals and human (PUBMED, MEDLINE, COCHRANE, and Google search. All the studies included showed noticeable regeneration of periodontal tissues with the use of BMP.

  3. Regenerate augmentation with bone marrow concentrate after traumatic bone loss

    OpenAIRE

    Jan Gessmann; Manfred Köller; Holger Godry; Thomas Armin Schildhauer; Dominik Seybold

    2012-01-01

    Distraction osteogenesis after post-traumatic segmental bone loss of the tibia is a complex and time-consuming procedure that is often complicated due to prolonged consolidation or complete insufficiency of the regenerate. The aim of this feasibility study was to investigate the potential of bone marrow aspiration concentrate (BMAC) for percutaneous regenerate augmentation to accelerate bony consolidation of the regenerate. Eight patients (age 22-64) with an average posttraumatic bone defect ...

  4. 阴道黏膜瓣在女复男易性病尿道延长术中的应用%Clinical applications of vaginal mucosal flap for urethral lengthening surgery in female-to-male patients

    Institute of Scientific and Technical Information of China (English)

    李旭东; 赵烨德; 周强; 张连杰; 唐乙

    2015-01-01

    Objective To investigate the vaginal mucosal flap for urethral Lengthening surgery in female-to-male patients. Methods There were 37 cases of female-to-male patients received urethral lengthening surgery with vaginal mucosal flap. Results All patients received urethral lengthening surgery were all successful with the original female urethra extended to the pubic symphysis. 4 cases of distal vaginal mucosal flap erosion. 2 cases of urinary fistula occurred,healed after debridement. Conclusions In the treatment of female-to-male patients, urethral lengthening surgery with vaginal mucosal flap not only reduced wound tension,but also reduced postoperative urinary stone disease resulting in hair problems.%目的:探讨阴道黏膜瓣行尿道延长术在女复男易性病手术中的应用。方法:对37例女复男易性病患者采用阴道黏膜瓣行尿道延长术。结果:全部患者尿道延长手术均获成功,尿道口由原来的女性尿道口延长至耻骨联合,4例发生阴道黏膜瓣远端与皮肤缝合处黏膜糜烂,二期愈合。2例发生尿瘘,二期清创缝合后痊愈。结论:在女复男易性病患者的治疗中,利用发育较好的阴道黏膜施行尿道延长术,不仅使术后切口张力减小,而且减少术后尿道毛发生长导致毛石症的困扰。

  5. Loss of ATRX or DAXX expression and concomitant acquisition of the alternative lengthening of telomeres phenotype are late events in a small subset of MEN-1 syndrome pancreatic neuroendocrine tumors

    OpenAIRE

    de Wilde, Roeland F.; Heaphy, Christopher M.; Maitra, Anirban; Meeker, Alan K.; Barish H Edil; Wolfgang, Christopher L; Ellison, Trevor A.; Schulick, Richard D; Molenaar, I. Quintus; Valk, Gerlof D.; Vriens, Menno R.; Rinkes, Inne HM Borel; Offerhaus, G. Johan A.; Ralph H. Hruban; Matsukuma, Karen E.

    2012-01-01

    Approximately 45% of sporadic well-differentiated pancreatic neuroendocrine tumors harbor mutations in either ATRX (alpha thalassemia/mental retardation X-linked) or DAXX (death domain-associated protein). These novel tumor suppressor genes encode nuclear proteins that interact with one another and function in chromatin remodeling at telomeric and peri-centromeric regions. Mutations in these genes are associated with loss of their protein expression and correlate with the alternative lengthen...

  6. Carbon nanohorns accelerate bone regeneration in rat calvarial bone defect

    Energy Technology Data Exchange (ETDEWEB)

    Kasai, Takao; Iizuka, Tadashi; Kanamori, Takeshi; Yokoyama, Atsuro [Department of Oral Functional Prosthodontics, Division of Oral Functional Science, Graduate School of Dental Medicine, Hokkaido University, Kita 13, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8586 (Japan); Matsumura, Sachiko; Shiba, Kiyotaka [Division of Protein Engineering, Cancer Institute, Japanese Foundation for Cancer Research, 3-8-31, Ariake, koutou-ku, Tokyo 135-8550 (Japan); Yudasaka, Masako; Iijima, Sumio, E-mail: tkasai@den.hokudai.ac.jp [Nanotube Research Center, National Institute of Advanced Industrial Science and Technology, Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8565 (Japan)

    2011-02-11

    A recent study showed that carbon nanohorns (CNHs) have biocompatibility and possible medical uses such as in drug delivery systems. It was reported that some kinds of carbon nanomaterials such as carbon nanotubes were useful for bone formation. However, the effect of CNHs on bone tissue has not been clarified. The purpose of this study was to evaluate the effect of CNHs on bone regeneration and their possible application for guided bone regeneration (GBR). CNHs dispersed in ethanol were fixed on a porous polytetrafluoroethylene membrane by vacuum filtration. Cranial defects were created in rats and covered by a membrane with/without CNHs. At two weeks, bone formation under the membrane with CNHs had progressed more than under that without CNHs and numerous macrophages were observed attached to CNHs. At eight weeks, there was no significant difference in the amount of newly formed bone between the groups and the appearance of macrophages was decreased compared with that at two weeks. Newly formed bone attached to some CNHs directly. These results suggest that macrophages induced by CNHs are related to bone regeneration. In conclusion, the present study indicates that CNHs are compatible with bone tissue and effective as a material for GBR.

  7. SWALLOWED FISH BONES IN MALI

    Directory of Open Access Journals (Sweden)

    Sacko HB

    2015-07-01

    Full Text Available Objective: To study the different aspects, clinical, diagnostic and therapeutic of 114 cases of fish bones in the upper digestive tract . Methods: One hundred fourteen patients with fish bones suspected in the upper digestive tract were admitted in our department between February 2010 and October 2012. Results: There was a predominance of the male: 66 men (58%. The average age of the patients was 26 years with extremes 3 to 62 years old. The tongue base and vallecula are constituted the principals locations 66.66%. In the majority of the cases the fish bones were removed by direct pharyngoscopy in 43.86 %. We have not notified any serious complications. Conclusion: Therefore this study shows the foreign fish bones are frequently just as well in children as adult. The fish bones are particularly lodged in tongue base. The classical methods of extraction are permit to remove the all foreign fish bones.

  8. Bone-seeking therapeutic radiopharmaceuticals

    Directory of Open Access Journals (Sweden)

    Srivastava Suresh C.

    2002-01-01

    Full Text Available Bone-seeking therapeutic radiopharmaceuticals are utilized on the basis of the radionuclide?s particulate emissions (primarily low to intermediate beta emission. The requirements therefore are different from those of bone imaging agents that consist mainly of short-lived single photon emitters. Lately, the therapeutic bone seeking radiopharmaceuticals have attained increasing importance due to their potential role in alleviating pain from osseous metastases in cancer patients, for the treatment of joint pain resulting from inflamed synovium (radiosynoviorthesis, or radiosynovectomy, or from various other forms of arthritic disease. There is, however, a paucity of published data on the bio-pharmacokinetics of these agents when used following intravenous administration for bone pain palliation. This paper will briefly review and summarize the presently available chemical and biopharmacokinetic information on the various clinically approved as well as experimental bone-localizing therapeutic radiopharmaceuticals, and make projections on their clinical application for the treatment of primary/metastatic cancer in bone.

  9. Bone healing around nanocrystalline hydroxyapatite, deproteinized bovine bone mineral, biphasic calcium phosphate, and autogenous bone in mandibular bone defects

    DEFF Research Database (Denmark)

    Broggini, Nina; Bosshardt, Dieter D; Jensen, Simon S;

    2015-01-01

    The individual healing profile of a given bone substitute with respect to osteogenic potential and substitution rate must be considered when selecting adjunctive grafting materials for bone regeneration procedures. In this study, standardized mandibular defects in minipigs were filled with nanocr......The individual healing profile of a given bone substitute with respect to osteogenic potential and substitution rate must be considered when selecting adjunctive grafting materials for bone regeneration procedures. In this study, standardized mandibular defects in minipigs were filled...... with nanocrystalline hydroxyapatite (HA-SiO), deproteinized bovine bone mineral (DBBM), biphasic calcium phosphate (BCP) with a 60/40% HA/β-TCP (BCP 60/40) ratio, or particulate autogenous bone (A) for histological and histomorphometric analysis. At 2 weeks, percent filler amongst the test groups (DBBM (35.65%), HA...

  10. Bone health in cancer patients

    DEFF Research Database (Denmark)

    Coleman, R; Body, J J; Aapro, M;

    2014-01-01

    cancer for many patients resulting in a major reduction in skeletal complications, reduced bone pain and improved quality of life. Secondly, many of the treatments we use to treat cancer patients have effects on reproductive hormones, which are critical for the maintenance of normal bone remodelling...... in the metastatic processes required for cancer dissemination, and there are emerging data showing that, at least in some clinical situations, the use of bone-targeted treatments can reduce metastasis to bone and has potential impact on patient survival.......There are three distinct areas of cancer management that make bone health in cancer patients of increasing clinical importance. First, bone metastases are common in many solid tumours, notably those arising from the breast, prostate and lung, as well as multiple myeloma, and may cause major...

  11. Distribution Principle of Bone Tissue

    CERN Document Server

    Fan, Yifang; Fan, Yubo; Xu, Zongxiang; Li, Zhiyu

    2009-01-01

    Using the analytic and experimental techniques we present an exploratory study of the mass distribution features of the high coincidence of centre of mass of heterogeneous bone tissue in vivo and its centroid of geometry position. A geometric concept of the average distribution radius of bone issue is proposed and functional relation of this geometric distribution feature between the partition density and its relative tissue average distribution radius is observed. Based upon the mass distribution feature, our results suggest a relative distance assessment index between the center of mass of cortical bone and the bone center of mass and establish a bone strength equation. Analysing the data of human foot in vivo, we notice that the mass and geometric distribution laws have expanded the connotation of Wolff's law, which implies a leap towards the quantitative description of bone strength. We finally conclude that this will not only make a positive contribution to help assess osteoporosis, but will also provide...

  12. Green Tea and Bone metabolism

    OpenAIRE

    Shen, Chwan-Li; Yeh, James K.; Cao, Jay; Wang, Jia-Sheng

    2009-01-01

    Osteoporosis is a major health problem in both elderly women and men. Epidemiological evidence has shown an association between tea consumption and the prevention of age-related bone loss in elderly women and men. Ingestion of green tea and green tea bioactive compounds may be beneficial in mitigating bone loss of this population and decreasing their risk of osteoporotic fractures. This review describes the effect of green tea or its bioactive components on bone health, with an emphasis on: (...

  13. Issues in modern bone histomorphometry☆

    OpenAIRE

    Recker, R R; Kimmel, D. B.; Dempster, D.; Weinstein, R S; Wronski, T.J.; Burr, D.B.

    2011-01-01

    This review reports on proceedings of a bone histomorphometry session conducted at the Fortieth International IBMS Sun Valley Skeletal Tissue Biology Workshop held on August 1, 2010. The session was prompted by recent technical problems encountered in conducting histomorphometry on bone biopsies from humans and animals treated with anti-remodeling agents such as bisphosphonates and RANKL antibodies. These agents reduce remodeling substantially, and thus cause problems in calculating bone remo...

  14. Playing with bone and fat

    DEFF Research Database (Denmark)

    Gimble, Jeffrey M.; Zvonic, Sanjin; Floyd, Z. Elisabeth;

    2006-01-01

    The relationship between bone and fat formation within the bone marrow microenvironment is complex and remains an area of active investigation. Classical in vitro and in vivo studies strongly support an inverse relationship between the commitment of bone marrow-derived mesenchymal stem cells or s...... or stromal cells to the adipocyte and osteoblast lineage pathways. In this review, we focus on the recent literature exploring the mechanisms underlying these differentiation events and discuss their implications relevant to osteoporosis and regenerative medicine....

  15. Bone and cancer: the osteoncology

    OpenAIRE

    Ibrahim, Toni; Mercatali, Laura; Amadori, Dino

    2013-01-01

    In recent years clinicians have witnessed a radical change in the relationship between bone and cancer, with in particular an increase in bone metastases incidence due to an improvement of patients survival. Bone metastases are responsible for the high morbidity in cancer patients with a strong clinical impact. For all these reasons, efforts have been directed to this important field with the foundation of the osteoncology, a new scientific and clinical branch involved in the management of pa...

  16. Anorexia nervosa and bone metabolism

    OpenAIRE

    Fazeli, Pouneh K.; Klibanski, Anne

    2014-01-01

    Anorexia nervosa (AN) is a psychiatric disorder characterized by self-induced starvation with a lifetime prevalence of 2.2% in women. The most common medical co-morbidity in women with AN is bone loss, with over 85% of women having bone mineral density values more than one standard deviation below an age comparable mean. The low bone mass in AN is due to multiple hormonal adaptations to under nutrition, including hypothalamic amenorrhea and growth hormone resistance. Importa...

  17. Expansion of the CHR bone code system

    International Nuclear Information System (INIS)

    This report describes the coding system used in the Center for Human Radiobiology (CHR) to identify individual bones and portions of bones of a complete skeletal system. It includes illustrations of various bones and bone segments with their respective code numbers. Codes are also presented for bone groups and for nonbone materials

  18. Dissociation of bone formation markers in bone metastasis of prostate cancer.

    OpenAIRE

    Koizumi, M; Maeda, H.; Yoshimura, K; Yamauchi, T.; Kawai, T.; Ogata, E

    1997-01-01

    To clarify the meaning and clinical value of bone formation markers in bone metastasis from prostate cancer, we investigated the bone formation markers carboxy-terminal propeptide of type I procollagen (PICP), bone-specific alkaline phosphatase (BA1-p) and osteocalcin, so-called bone gla protein (BGP) in 43 prostate cancer patients with and 46 patients without overt bone metastasis. Patients with bone metastasis were evaluated repeatedly by bone scan at intervals of 3-6 months. The expression...

  19. Craniometadiaphyseal dysplasia, wormian bone type.

    Science.gov (United States)

    Santolaya, J M; Hall, C M; García-Miñaur, S; Delgado, A

    1998-05-18

    We report on a 4-year-old boy with craniometadiaphyseal dysplasia (CMDD), wormian bone type. Component manifestations include a large head with prominent forehead, skull changes showing multiple wormian bones, wide long tubular bones without the usual metaphyseal flare, wide and short tubular bones without the normal diaphyseal constriction, and wide ribs and clavicles. In addition to these findings, the propositus, his brother, his father, and a paternal aunt all have parietal protuberances, which seem not related to CMDD. Parental consanguineity supports the autosomal recessive transmission of the condition. PMID:9605592

  20. The Dragon Bone Collectors

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Finding of a dinosaur fossil skeleton sparks excitement among paleontologists and locals in a poor Henan village Avillager’s accidental discovery four years ago has made known to the world a rich mine of dinosaur fossils in Ruyang County,central China’s Henan Province.At the same time,the fate of the small village has been changed. Li Chui,a farmer in Shaping Village, thought he had found bones of a"dragon"when he dug up stones for his new house on an April morning in 2005.

  1. Bones of the Earth

    Directory of Open Access Journals (Sweden)

    Jose Miguel Correa

    2014-06-01

    Full Text Available The film Bones of the Earth (Riglin, Cunninham & Correa, 2014 is an experience in collective inquiry and visual creation based on arts-based research. Starting from the meeting of different subjectivities and through dialogue, planning, shooting and editing, an audiovisual text that reconstructs a reflexive process of collective creation is built. A sense of community, on-going inquiry, connections and social commitment inform the creative process. As a result, the video’s nearly five intense minutes are a metaphor for the search for personal meaning, connection with nature and intersubjective positioning in a world that undergoes constant change.

  2. Can Na18F PET/CT Be Used to Study Bone Remodeling in the Tibia When Patients Are Being Treated with a Taylor Spatial Frame?

    Directory of Open Access Journals (Sweden)

    Henrik Lundblad

    2014-01-01

    Full Text Available Monitoring and quantifying bone remodeling are of interest, for example, in correction osteotomies, delayed fracture healing pseudarthrosis, bone lengthening, and other instances. Seven patients who had operations to attach an Ilizarov-derived Taylor Spatial Frame to the tibia gave informed consent. Each patient was examined by Na18F PET/CT twice, at approximately six weeks and three months after the operation. A validated software tool was used for the following processing steps. The first and second CT volumes were aligned in 3D and the respective PET volumes were aligned accordingly. In the first PET volume spherical volumes of interest (VOIs were delineated for the crural fracture and normal bone and transferred to the second PET volume for SUVmax evaluation. This method potentially provides clinical insight into questions such as, when has the bone remodeling progressed well enough to safely remove the TSF? and when is intervention required, in a timelier manner than current methods? For example, in two patients who completed treatment, the SUVmax between the first and second PET/CT examination decreased by 42% and 13%, respectively. Further studies in a larger patient population are needed to verify these preliminary results by correlating regional Na18F PET measurements to clinical and radiological findings.

  3. Raman spectroscopy of bone metastasis

    Science.gov (United States)

    Esmonde-White, Karen A.; Sottnik, Joseph; Morris, Michael; Keller, Evan

    2012-02-01

    Raman spectroscopy of bone has been used to characterize chemical changes occurring in diseases such as osteoporosis, osteoarthritis and osteomyelitis. Metastasis of cancer into bone causes changes to bone quality that are similar to those observed in osteoporosis, such as decreased bone strength, but with an accelerated timeframe. In particular, osteolytic (bone degrading) lesions in bone metastasis have a marked effect on patient quality of life because of increased risk of fractures, pain, and hypercalcemia. We use Raman spectroscopy to examine bone from two different mouse models of osteolytic bone metastasis. Raman spectroscopy measures physicochemical information which cannot be obtained through standard biochemical and histological measurements. This study was reviewed and approved by the University of Michigan University Committee on the Care and Use of Animals. Two mouse models of prostate cancer bone metastasis, RM1 (n=3) and PC3-luc (n=4) were examined. Tibiae were injected with RM1 or PC3-luc cancer cells, while the contralateral tibiae received a placebo injection for use as controls. After 2 weeks of incubation, the mice were sacrificed and the tibiae were examined by Raman microspectroscopy (λ=785 nm). Spectroscopic markers corresponding to mineral stoichiometry, bone mineralization, and mineral crystallinity were compared in spectra from the cancerous and control tibiae. X-ray imaging of the tibia confirmed extensive osteolysis in the RM1 mice, with tumor invasion into adjoining soft tissue and moderate osteolysis in the PC3-luc mice. Raman spectroscopic markers indicate that osteolytic lesions are less mineralized than normal bone tissue, with an altered mineral stoichiometry and crystallinity.

  4. Broken Bones, Sprains, and Strains (For Parents)

    Science.gov (United States)

    ... 5 Things to Know About Zika & Pregnancy Broken Bones, Sprains, and Strains KidsHealth > For Parents > Broken Bones, ... home. What to Do: For a Suspected Broken Bone: Do not move a child whose injury involves ...

  5. Bones, Muscles, and Joints: The Musculoskeletal System

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy Bones, Muscles, and Joints KidsHealth > For Parents > Bones, Muscles, ... able to stand, walk, run, or even sit. Bones and What They Do From our head to ...

  6. Molecular mechanism of bone formation and regeneration

    Institute of Scientific and Technical Information of China (English)

    Akira Yamaguchi

    2008-01-01

    @@ Bone formation and regeneration are mediated by the coordinate action of various factors. Among these, bone morphogenetic protein (BMP) and runt-related gene 2 (Runx2) play crucial roles in bone formation.

  7. Osteoporosis: Peak Bone Mass in Women

    Science.gov (United States)

    ... Bone Health for Lupus Patients Bone Health and Anorexia Nervosa Partner Resources Screening Tests and Immunizations Guidelines for ... calcium. Physical Activity. Girls and boys and young adults who exercise regularly generally achieve greater peak bone ...

  8. Bone Mass Measurement: What the Numbers Mean

    Science.gov (United States)

    ... supported by your browser. Home Bone Basics Bone Mass Measurement: What the Numbers Mean Publication available in: ... been one or more osteoporotic fractures. Low Bone Mass Versus Osteoporosis The information provided by a BMD ...

  9. Alternative lengthening of telomeres phenotype in malignant vascular tumors is highly associated with loss of ATRX expression and is frequently observed in hepatic angiosarcomas.

    Science.gov (United States)

    Liau, Jau-Yu; Tsai, Jia-Huei; Yang, Ching-Yao; Lee, Jen-Chieh; Liang, Cher-Wei; Hsu, Hung-Han; Jeng, Yung-Ming

    2015-09-01

    Alternative lengthening of telomeres (ALT) is a mechanism using homologous recombination to maintain telomere length and sustain limitless replicability of cancer cells. Recently, ALT has been found to be associated with inactivation of either α-thalassemia/mental retardation syndrome X-linked (ATRX) or death domain-associated (DAXX) protein. In this study, 119 tumors (88 angiosarcomas, 11 epithelioid hemangioendotheliomas, and 20 Kaposi sarcomas) were analyzed to determine the ALT status, its relationship to loss of ATRX/DAXX expression, and the clinicopathological features. In addition, the mutation status in the telomerase reverse transcriptase gene (TERT) promoter was also studied. Loss of ATRX expression was observed in 21% (16/77) of the primary angiosarcomas and 9% (1/11) of epithelioid hemangioendotheliomas. DAXX expression was intact in all but 2 ATRX-deficient angiosarcomas. Telomere-specific fluorescence in situ hybridization assay showed 28% (17/61) of the primary angiosarcomas were ALT positive. Remarkably, ALT was highly associated with loss of ATRX expression: all but 2 ALT-positive angiosarcomas were ATRX deficient. Notably, hepatic angiosarcomas were frequently ATRX deficient (8/13) and/or ALT positive (8/12). None of the secondary angiosarcomas were ATRX/DAXX deficient or ALT positive. The only ATRX-deficient epithelioid hemangioendothelioma was positive for ALT. Forty-seven angiosarcomas were tested for TERT promoter mutation. Despite the fact that angiosarcoma occurs most commonly in sun-damaged skin, mutation was detected in only 1 radiation-associated angiosarcoma (2%). We conclude that ALT is an important telomere maintenance mechanism in primary angiosarcomas. This feature is highly associated with loss of ATRX expression and is frequently observed in hepatic angiosarcomas. PMID:26190196

  10. Augmented telomerase activity, reduced telomere length and the presence of alternative lengthening of telomere in renal cell carcinoma: plausible predictive and diagnostic markers.

    Science.gov (United States)

    Pal, Deeksha; Sharma, Ujjawal; Khajuria, Ragini; Singh, Shrawan Kumar; Kakkar, Nandita; Prasad, Rajendra

    2015-05-15

    In this study, we analyzed 100 cases of renal cell carcinoma (RCC) for telomerase activity, telomere length and alternative lengthening of telomeres (ALT) using the TRAP assay, TeloTTAGGG assay kit and immunohistochemical analysis of ALT associated promyelocytic leukemia (PML) bodies respectively. A significantly higher (P=0.000) telomerase activity was observed in 81 cases of RCC which was correlated with clinicopathological features of tumor for instance, stage (P=0.008) and grades (P=0.000) but not with the subtypes of RCC (P = 0.355). Notwithstanding, no correlation was found between telomerase activity and subtypes of RCC. Strikingly, the telomere length was found to be significantly shorter in RCC (P=0.000) to that of corresponding normal renal tissues and it is well correlated with grades (P=0.016) but not with stages (P=0.202) and subtypes (P=0.669) of RCC. In this study, telomere length was also negatively correlated with the age of patients (r(2)=0.528; P=0.000) which supports the notion that it could be used as a marker for biological aging. ALT associated PML bodies containing PML protein was found in telomerase negative cases of RCC. It suggests the presence of an ALT pathway mechanism to maintain the telomere length in telomerase negative RCC tissues which was associated with high stages of RCC, suggesting a prevalent mechanism for telomere maintenance in high stages. In conclusion, the telomerase activity and telomere length can be used as a diagnostic as well as a predictive marker in RCC. The prevalence of ALT mechanism in high stages of RCC is warranted for the development of anti-ALT inhibitors along with telomerase inhibitor against RCC as a therapeutic approach. PMID:25769384

  11. The factors determining pathways of lengthening of telomere%端粒延长途径选择的影响因素

    Institute of Scientific and Technical Information of China (English)

    汪英颖

    2009-01-01

    肿瘤发生与端粒维持密切相关,大部分肿瘤细胞的端粒维持是通过端粒酶途径,而少部分肿瘤细胞是通过非端粒酶依赖途径,即所谓的端粒替代延长机制实现端粒维持.端粒延长途径的选择在不同水平如细胞、蛋白、基因水平会受多因素的影响即端粒本身结构的完整性、染色体的稳定性、细胞周期、组蛋白等因素影响.了解这些影响因素,有利于进一步研究阻断端粒延长途径的药物,从而控制肿瘤的无限增长,有效治疗肿瘤.%Telomere maintenance is correlated with the genesis of tumor,majority of tumors depend on the telomerase to maintain its function,but minority of tumors use pathway independent of the telomernse,that is the alternative way of lengthening(ALT).This choice of pathway is determined by several factors in different aspects,such as cells level,proteins level and genes level,the factors include the integrity of the telomere,the chromosome stability,the cell cycle and histone.Complete understandings of these factors help us to find some drugs to inhibit this alternative pathway and control the progression of the tumor,and then we can treat tumors more efficiently.

  12. Porous hydroxyapatite for artificial bone applications

    OpenAIRE

    I. Sopyan et al

    2007-01-01

    Hydroxyapatite (HA) has been used clinically for many years. It has good biocompatibility in bone contact as its chemical composition is similar to that of bone material. Porous HA ceramics have found enormous use in biomedical applications including bone tissue regeneration, cell proliferation, and drug delivery. In bone tissue engineering it has been applied as filling material for bone defects and augmentation, artificial bone graft material, and prosthesis revision surgery. Its high surfa...

  13. ICTP in Bone Metastases of Lung Cancer

    OpenAIRE

    Franjević, Ana; Pavićević, Radomir; Bubanović, Gordana

    2011-01-01

    Bone metastases often appear in advanced stages of lung cancer. They are the result of modulation of bone metabolism by tumor cells that migrated into bone microenvironment and degraded bone organic matrix. Measurement of C-terminal telopeptide of type I collagen (ICTP) in the serum of subjects with lung cancer with and without bone metastases and healthy population is the way to explore bone resorption. In 343 subjects included in this research ICTP level was significantly higher...

  14. Cancer to bone: a fatal attraction

    OpenAIRE

    Weilbaecher, Katherine N.; Guise, Theresa A.; McCauley, Laurie K

    2011-01-01

    When cancer metastasizes to bone, considerable pain and deregulated bone remodelling occurs, greatly diminishing the possibility of cure. Metastasizing tumour cells mobilize and sculpt the bone microenvironment to enhance tumour growth and to promote bone invasion. Understanding the crucial components of the bone microenvironment that influence tumour localization, along with the tumour-derived factors that modulate cellular and protein matrix components of bone to favour tumour expansion and...

  15. Parathyroid hormone and bone healing

    DEFF Research Database (Denmark)

    Ellegaard, M; Jørgensen, N R; Schwarz, P

    2010-01-01

    , no pharmacological treatments are available. There is therefore an unmet need for medications that can stimulate bone healing. Parathyroid hormone (PTH) is the first bone anabolic drug approved for the treatment of osteoporosis, and intriguingly a number of animal studies suggest that PTH could be beneficial...

  16. Complications of occipital bone pneumatization.

    Science.gov (United States)

    Moss, Mary; Biggs, Michael; Fagan, Paul; Forer, Martin; Davis, Martin; Roche, Jim

    2004-06-01

    Four cases of occipital bone pneumatization and subsequent complications are described, which include a pathological fracture of C1 and the occipital bone, spontaneous subcutaneous emphysema and pneumatocele formation. Reviews of the published literature and possible aetiological factors have been discussed. PMID:15230770

  17. Fusion of the ear bones

    Science.gov (United States)

    ... caused by: Birth (congenital) defect Infection Injury Symptoms Fusion of the bones leads to hearing loss, because the bones are not moving and vibrating in reaction to sound waves. Images Ear anatomy Medical findings based on ear anatomy References Torres AI, ...

  18. Nonallograft osteoconductive bone graft substitutes.

    Science.gov (United States)

    Bucholz, Robert W

    2002-02-01

    An estimated 500,000 to 600,000 bone grafting procedures are done annually in the United States. Approximately (1/2) of these surgeries involve spinal arthrodesis whereas 35% to 40% are used for general orthopaedic applications. Synthetic bone graft substitutes currently represent only 10% of the bone graft market, but their share is increasing as experience and confidence in their use are accrued. Despite 15 to 20 years of clinical experience with various synthetic substitutes, there have been few welldesigned, controlled clinical trials of these implants. Synthetic bone graft substitutes consist of hydroxyapatite, tricalcium phosphate, calcium sulfate, or a combination of these minerals. Their fabrication technique, crystallinity, pore dimensions, mechanical properties, and resorption rate vary. All synthetic porous substitutes share numerous advantages over autografts and allografts including their unlimited supply, easy sterilization, and storage. However, the degree to which the substitute provides an osteoconductive structural framework or matrix for new bone ingrowth differs among implants. Disadvantages of ceramic implants include brittle handling properties, variable rates of resorption, poor performance in diaphyseal defects, and potentially adverse effects on normal bone remodeling. These inherent weaknesses have refocused their primary use to bone graft extenders and carriers for pharmaceuticals. The composition, histologic features, indications, and clinical experience of several of the synthetic bone graft substitutes approved for orthopaedic use in the United States are reviewed. PMID:11937865

  19. Unusual sutural bones at pterion

    OpenAIRE

    Nayak SB; KV S

    2008-01-01

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

  20. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... be more useful in identifying bone and joint injuries (e.g., meniscal and ligament tears in the knee, rotator cuff and labrum tears in the shoulder) and in imaging of the spine (because both the bones and the spinal cord can ... suspected spine injury or other complicated injuries, 3-D reconstructed CT ...

  1. Bone Grafting the Cleft Maxilla

    Science.gov (United States)

    ... systemic disease such as diabetes, or has poor oral hygiene, the risk that the graft may fail increases even more. Once the bone graft has been placed, there are three options that ... replacement (dental bridge); or 3) dental metallic bone implants. The ...

  2. Unusual sutural bones at pterion

    Directory of Open Access Journals (Sweden)

    Nayak SB

    2008-08-01

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

  3. Bone metabolism in thyroidectomized patients

    International Nuclear Information System (INIS)

    The bone mineral content in the patients who had undergone operation for thyroid carcinoma was measured by quantitative CT. Thirty-eight cases were enrolled as the subjects. All cases were papillary adenocarcinoma of the thyroid. The totally thyroidectomized group consisted of 3 males and 14 females, and the non-totally thyroidectomized group (post-lobectomy) 3 males and 18 females. Thirty-eight healthy males and females were assigned to the control group. For evaluation of bone mineral content, quantitative CT was used and bone mineral content in the patient's lumbar vertebrae was measured. Concurrently, bone metabolic parameter in serum was determined. No significant difference was observed in the mean bone mineral content among the above three groups. To make correction by sex and age, BMC-index was defined as the value that the bone mineral content in each case was divided by the standard mean by the same age and sex. No significant difference was observed in BMC-index among the above three groups. No significant correlation was observed in serum calcitonin level with the bone mineral content and BMC-index. It suggests that no influence is exerted on bone metabolism if serum calcitonin is maintained in the physiological level. (author)

  4. Low Bone Mass in Thalassemia

    Science.gov (United States)

    4 Low Bone Mass in Thalassemia • In addition to a diet rich in calcium and vitamin D, your doctor may recommend taking calcium ... What can be done to treat low bone mass? Following all of the above prevention measures is ...

  5. Ivory Osteoma Of Temporal Bone

    Directory of Open Access Journals (Sweden)

    Ravi Meher

    2006-03-01

    Full Text Available Osteomas are slow growing bony tumors common in fronto-ethmoid regions and rare in temporal bone. These are usually asymptomatic and require treatment mainly for cosmetic reasons. We describe a case of temporal bone osteoma in a female.

  6. The healing of fractured bones

    Energy Technology Data Exchange (ETDEWEB)

    Bacon, G.E. [Central Electricity Generating Board, Cheltenham (United Kingdom)

    1997-04-01

    A method utilising neutron beams of width 1 mm, used on D1B (2.4 A) and D20 (1.3 A) to study the healing of fractured bones is presented. It is found that the callus bone uniting the fractured tibia of a sheep, whose healing had been encouraged by daily mechanical vibration over a period of three months, showed no trace of the large preferential vertical orientation of the apatite crystals which is characteristic of the normal bone. Nevertheless the bone had regained about 60% of its mechanical strength and the callus bone, although not oriented, was well crystallized. It is considered that the new monochromator for D20, expected to give increased intensity at 2.5 A, will be of considerable advantage. (author). 2 refs.

  7. Ethnic Differences in Bone Health

    Directory of Open Access Journals (Sweden)

    Ayse eZengin

    2015-03-01

    Full Text Available There are differences in bone health between ethnic groups in both men and in women. Variations in body size and composition are likely to contribute to reported differences. Most studies report ethnic differences in areal bone mineral density (aBMD which do not consistently parallel ethnic patterns in fracture rates. This suggests that other parameters beside aBMD should be considered when determining fracture risk between and within populations, including other aspects of bone strength: bone structure and microarchitecture as well muscle strength (mass, force generation, anatomy and fat mass. We review what is known about differences in bone-densitometry derived outcomes between ethnic groups and the extent to which they account for the differences in fracture risk. Studies are included that were published primarily between 1994 – 2014. A ‘one size fits all approach’ should not be used to understand better ethnic differences in fracture risk.

  8. Investigations of Diabetic Bone Disease

    DEFF Research Database (Denmark)

    Linde, Jakob Starup

    Diabetes mellitus is associated with an increased risk of fracture with and current fracture predictors underestimate fracture risk in both type 1 and type 2 diabetes. Thus, further understanding of the underlying causes of diabetic bone disease may lead to better fracture predictors and preventive...... measures in patients with diabetes. This PhD thesis reports the results of two systematic reviews and a meta-analysis, a state-of-the-art intervention study, a clinical cross-sectional study and a registry-based study all examining the relationship between diabetes, glucose, and bone. Patients with type 2...... diabetes had lower bone turnover markers compared to patients with type 1 diabetes and bone mineral density and tissue stiffness were increased in patients with type 2 diabetes. The bone turnover markers were inversely associated with blood glucose in patients with diabetes and both an oral glucose...

  9. The usefulness of bone and bone-marrow scintigraphy in the detection of bone lesion in patients with multiple myeloma

    International Nuclear Information System (INIS)

    We used a combination of bone and bone-marrow scintigraphy to study 15 patients with multiple myeloma (7 in untreated group and 8 in chemotherapy group). Of the 3 cases in untreated group whose 99mTc-methylene diphosphonate (MDP) bone scans showed no abnormality, one had abnormal bone-marrow scintigraphy. In other 4 cases of untreated group whose 99mTc-MDP bone scan showed cold defects, 99mTc-sulfur colloid bone-marrow scintigraphy clearly delineated the areas of tumor-cell invasion. In all chemotherapy cases, multiple hot spots were observed on bone scintigram, but abnormalities were not recognized on bone-marrow scintigram in all of their lesions. In conclusion, the combination technique of bone and bone-marrow scintigraphy was a useful method in evaluating bone lesions in patients with multiple myeloma. (author)

  10. Bone composition: relationship to bone fragility and antiosteoporotic drug effects.

    Science.gov (United States)

    Boskey, Adele L

    2013-01-01

    The composition of a bone can be described in terms of the mineral phase, hydroxyapatite, the organic phase, which consists of collagen type I, noncollagenous proteins, other components and water. The relative proportions of these various components vary with age, site, gender, disease and treatment. Any drug therapy could change the composition of a bone. This review, however, will only address those pharmaceuticals used to treat or prevent diseases of bone: fragility fractures in particular, and the way they can alter the composition. As bone is a heterogeneous tissue, its composition must be discussed in terms of the chemical makeup, properties of its chemical constituents and their distributions in the ever-changing bone matrix. Emphasis, in this review, is placed on changes in composition as a function of age and various diseases of bone, particularly osteoporosis. It is suggested that while some of the antiosteoporotic drugs can and do modify composition, their positive effects on bone strength may be balanced by negative ones. PMID:24501681

  11. Progesterone and Bone: Actions Promoting Bone Health in Women

    Directory of Open Access Journals (Sweden)

    Vanadin Seifert-Klauss

    2010-01-01

    Full Text Available Estradiol (E2 and progesterone (P4 collaborate within bone remodelling on resorption (E2 and formation (P4. We integrate evidence that P4 may prevent and, with antiresorptives, treat women's osteoporosis. P4 stimulates osteoblast differentiation in vitro. Menarche (E2 and onset of ovulation (P4 both contribute to peak BMD. Meta-analysis of 5 studies confirms that regularly cycling premenopausal women lose bone mineral density (BMD related to subclinical ovulatory disturbances (SODs. Cyclic progestin prevents bone loss in healthy premenopausal women with amenorrhea or SOD. BMD loss is more rapid in perimenopause than postmenopause—decreased bone formation due to P4 deficiency contributes. In 4 placebo-controlled RCTs, BMD loss is not prevented by P4 in postmenopausal women with increased bone turnover. However, 5 studies of E2-MPA co-therapy show greater BMD increases versus E2 alone. P4 fracture data are lacking. P4 prevents bone loss in pre- and possibly perimenopausal women; progesterone co-therapy with antiresorptives may increase bone formation and BMD.

  12. Limb bone morphology, bone strength, and cursoriality in lagomorphs.

    Science.gov (United States)

    Young, Jesse W; Danczak, Robert; Russo, Gabrielle A; Fellmann, Connie D

    2014-10-01

    The primary aim of this study is to broadly evaluate the relationship between cursoriality (i.e. anatomical and physiological specialization for running) and limb bone morphology in lagomorphs. Relative to most previous studies of cursoriality, our focus on a size-restricted, taxonomically narrow group of mammals permits us to evaluate the degree to which 'cursorial specialization' affects locomotor anatomy independently of broader allometric and phylogenetic trends that might obscure such a relationship. We collected linear morphometrics and μCT data on 737 limb bones covering three lagomorph species that differ in degree of cursoriality: pikas (Ochotona princeps, non-cursorial), jackrabbits (Lepus californicus, highly cursorial), and rabbits (Sylvilagus bachmani, level of cursoriality intermediate between pikas and jackrabbits). We evaluated two hypotheses: cursoriality should be associated with (i) lower limb joint mechanical advantage (i.e. high 'displacement advantage', permitting more cursorial species to cycle their limbs more quickly) and (ii) longer, more gracile limb bones, particularly at the distal segments (as a means of decreasing rotational inertia). As predicted, highly cursorial jackrabbits are typically marked by the lowest mechanical advantage and the longest distal segments, non-cursorial pikas display the highest mechanical advantage and the shortest distal segments, and rabbits generally display intermediate values for these variables. Variation in long bone robusticity followed a proximodistal gradient. Whereas proximal limb bone robusticity declined with cursoriality, distal limb bone robusticity generally remained constant across the three species. The association between long, structurally gracile limb bones and decreased maximal bending strength suggests that the more cursorial lagomorphs compromise proximal limb bone integrity to improve locomotor economy. In contrast, the integrity of distal limb bones is maintained with increasing

  13. Bone Biochemistry on the International Space Station

    Science.gov (United States)

    Smith, Scott M.; Heer, Martina; Zwart, Sara R.

    2016-01-01

    Bone biochemical measures provide valuable insight into the nature and time course of microgravity effects on bone during space flight, where imaging technology cannot be employed. Increased bone resorption is a hallmark of space flight, while markers of bone formation are typically unchanged or decreased. Recent studies (after the deployment to ISS of the advanced resistive exercise device, ARED), have documented that astronauts with good nutritional intake (e.g., maintenance of body mass), good vitamin D status, and exercise maintained bone mineral density. These data are encouraging, but crewmembers exercising on the ARED do have alterations in bone biochemistry, specifically, bone resorption is still increased above preflight levels, but bone formation is also significantly increased. While this bone remodeling raises questions about the strength of the resulting bone, however documents beneficial effects of nutrition and exercise in counteracting bone loss of space flight.

  14. Biology of Bone Tissue: Structure, Function, and Factors That Influence Bone Cells

    OpenAIRE

    2015-01-01

    Bone tissue is continuously remodeled through the concerted actions of bone cells, which include bone resorption by osteoclasts and bone formation by osteoblasts, whereas osteocytes act as mechanosensors and orchestrators of the bone remodeling process. This process is under the control of local (e.g., growth factors and cytokines) and systemic (e.g., calcitonin and estrogens) factors that all together contribute for bone homeostasis. An imbalance between bone resorption and formation can res...

  15. Use of Spongious Bone Chips and Fascia Temporalis in Alveolar Bone Defects

    OpenAIRE

    TÜZ, Hakan H.; AKAL, Ümit K.; CAMBAZOĞLU, Mine; KİŞNİŞCİ, Reha Ş.

    2004-01-01

    Graft materials are used for inducement of regeneration in bone defects. Organic and synthetic bone graft materials facilitate remodelation or healing of the bone and induce new bone formation in the area of bone resorption caused by pathological, traumatic, and physiological reasons. The aim of this study was to evaluate the effects of spongious allogenic bone graft and fascia temporalis membranous collagen tissue on the healing of bone defects clinically and radiologically. The study was c...

  16. PENGGUNAAN BONE GRAFT PADA PERAWATAN KERUSAKAN TULANG PERIODONTAL (Used Bone Graft for Periodontal Defect Treatment)

    OpenAIRE

    Elly Munadziroh; Mohamad Rubianto; Asti Meizarini

    2015-01-01

    Generally the signs and symptoms of advances periodontal disease are periodontal pockets formation to alveolar bone defect. Bone defect treated with placement a preparation material to promote new bone formation. Tissue transplantation were developed, to recontsruct bone defect with the placement of bone graft material. This paper will discuss the used of demineralied freeze dried bone allograft (DFDBA) and anorganic bone mineral combined with synthetic 15 amino acid sequence within type I co...

  17. Re-evaluation of bone pain in patients with type 1 Gaucher disease suggests that bone crises occur in small bones as well as long bones.

    Science.gov (United States)

    Baris, Hagit N; Weisz Hubshman, Monika; Bar-Sever, Zvi; Kornreich, Liora; Shkalim Zemer, Vered; Cohen, Ian J

    2016-09-01

    Bone crises in type 1 Gaucher disease are reported in long bones and occasionally in weight bearing bones and other bones, but rarely in small bones of the hands and feet. We retrospectively examined the incidence of bone pain in patients followed at the Rabin Medical Center, Israel, before and following the initiation of enzyme replacement therapy (ERT) and evaluated them for bone crises. Of 100 type I Gaucher disease patients, 30 (30%) experienced one or more bone crises. Small bone crises represented 31.5% of all bone crises and were always preceded by crises in other bones. While the incidence of long bone crises reduced after the initiation of ERT, small bone crises increased. Almost 60% of patients with bone crises were of the N370S/84GG genotype suggesting a greater susceptibility of N370S/84GG patients to severe bone complications. These patients also underwent the greatest number of splenectomies (70.6% of splenectomised patients). Splenectomised patients showed a trend towards increased long and small bone crises after surgery. Active investigation of acute pain in the hands and feet in patients in our cohort has revealed a high incidence of small bone crises. Physicians should consider imaging studies to investigate unexplained pain in these areas. PMID:26051481

  18. Bone microdamage and cell apoptosis

    Directory of Open Access Journals (Sweden)

    Noble B.

    2003-12-01

    Full Text Available Accumulation of microdamage in bone leads to the reduced strength of our skeleton. In health, bone adapts to the prevailing mechanical needs of the organism and is also capable of self-repair, sensing, removing and replacing damaged or mechanically insufficient volumes of bone. In disease and old age these characteristics are reduced. In order to undertake both of the processes of functional adaptation and repair the bone resorbing and forming cells must be very accurately targeted to areas of physiological need. The mechanism by which cells are precisely targeted to areas requiring repair is both clinically relevant and poorly understood. The osteocyte has been assumed to play a role in sensing damage and signaling for its removal, due largely to its abundance throughout the mineralized bone matrix. However, until recently there has been little evidence that osteocyte function is modified in the vicinity of the microdamage. Here I outline the possibility that the targeted removal of bone containing microcracks might involve signals derived from the apoptotic death of the osteocyte. I shall discuss data that support or refute this view and will consider the possible molecular mechanisms by which controlled cell death might contribute to the signals for repair in the light of work involving cells in bone and other tissue systems.

  19. Expression of alternative lengthening telomere in human bone marrow mesenchymal stem cells%端粒延伸替代途径在人骨髓间充质干细胞中的表达和作用

    Institute of Scientific and Technical Information of China (English)

    赵强; 张丽红; 吴珊; 何旭; 石英爱

    2010-01-01

    目的:分离、培养人骨髓间充质干细胞(hMSCs),观察端粒延伸替代途径相关的白血病前髓淋巴细胞小体(PML)在骨髓间充质干细胞中的表达情况.明确其在hMSCs自我更新和分裂增殖过程中的作用.方法:Percoll梯度离心法分离培养hMSCs,免疫细胞化学染色方法检测PML小体在hMSCs中的表达率.结果:P1、P3和P5代hMSCs中未见明显PML小体表达;P7代hMSCs中可见PML小体在细胞胞核中呈阳性表达.表现为胞核内出现棕黄色颗粒,表达率为(16.1±0.6)%;P9和P11代hMSCs中亦可见PML小体表达,阳性率分别为(16.8±2.6)%和(45.8±9.5)%,P11代hMSCs PML小体表达率高于P7代hMSCs(P<0.05).结论:随着hMSCs传代次数的增加,端粒延伸替代途径逐渐出现发挥其延长端粒长度的作用,进而维持细胞的增殖和自我更新的能力.

  20. Plutonium microdistribution in human bone

    International Nuclear Information System (INIS)

    The amount and location of plutonium in bone from three humans injected during the mid-1940's has been studied by autoradiography and alpha particle spectrometry. Concentrations are similar on endosteal surfaces, Haversian canal surfaces and periosteal surfaces of long bone midshafts 17 months after injection. Endosteal surface concentrations are higher in the axial skeleton than in the appendicular skeleton 15 and 17 months post injection. For dosimetric purposes, volume deposits may be considered to be infinitely thick whereas surface deposits may be considered to have zero thickness. Secondary surface deposits are dosimetrically important, even when the plutonium is almost completely deposited in bone volume

  1. The effects of hypoxia-inducible factor (HIF)-1α protein on bone regeneration during distraction osteogenesis: an animal study.

    Science.gov (United States)

    Jiang, X; Zhang, Y; Fan, X; Deng, X; Zhu, Y; Li, F

    2016-02-01

    The aim of this study was to observe the effect of hypoxia-inducible factor (HIF)-1α on bone regeneration during distraction osteogenesis (DO). Fifty-one New Zealand white rabbits underwent mandibular lengthening with a distraction rate of 2mm/day, and were divided randomly into three groups (17 in each). Group C rabbits received 20 μg rHIF-1α, group B received 10 μg rHIF-1α, and group A received 100 μl saline injection in the distraction gap every day for 10 days. Radionuclide bone imaging (RBI), computed tomography, dual energy X-ray absorptiometry, radiography, histology, and three-point bend testing were performed. RBI showed that the uptake ratio in group B (1.41 ± 0.25, P=0.013) and group C (1.64 ± 0.37, P<0.001) was higher than that in group A (1.01 ± 0.26). The bone mineralization density and bone mineralization content in group C were highest among the three groups. Radiology and histology findings indicated more callus regeneration in groups C and B. Mechanical testing demonstrated that the ultimate force in group C (289.71 ± 43.31N, n=6) was 1.49-fold (P<0.001) that of group A and 1.20-fold (P=0.012) that of group B. HIF-1α may represent a new agent to promote DO by accelerating osteogenesis and mineralization.

  2. 牙冠延长术应用于后牙残根的临床研究%Clinical Report of Application in Residual Root of Molar Crown Lengthening Surgery

    Institute of Scientific and Technical Information of China (English)

    莫浩勋; 卢建峰; 李衬眉

    2011-01-01

    Objective To observe the clinical effect of restoration of residual root of molar with crown lengthening surgery. Methods Fifteen residual roots were included in this study. Crown lengthening surgery was first conducted and then post-core crowns were fabricated in all the cases. Then clinical effects were evaluated. Results All cases succeeded. The color of the gingival margin looked normal and the crowns were in good periodontal condition. Conclusion Crown lengthening surgery is an effective method for the protection and restoration of residual root,but should be used properly.%目的 观察牙冠延长术应用于后牙残根保留的效果.方法 选取远中缺损的后牙残根15颗,患者15例,应用牙冠延长术完成牙周软组织和牙槽骨硬组织的外科治疗,形成牙本质肩领,术后1周拆线,3个月后行桩核及冠桥修复.永久修复后2周复查,观察疗效.结果 15颗后牙残根无不适症状,术区牙龈颜色、形态和质地恢复正常,修复体无松动、脱落,基本恢复咀嚼功能,患者满意.结论 牙冠延长术有利于后牙残根的保留和修复,但要注意适应证的选择.

  3. Partial Resection of Penis Lengthening (A Report of 4 Cases)%阴茎部分切除同期延长术(附4例报告)

    Institute of Scientific and Technical Information of China (English)

    张中革; 刘有智

    2014-01-01

    Objective To observe the partial resection of penis lengthening in the treatment of young adult penile cancer requires to keep the therapeutic function of patients. Methods 4 patients with stage I (T1-2N0M0) in patients with carcinoma of penis penis lengthening of partial resection, observed the ef ect of treatment. Results The two patients fol owed up for two and a half years, patients with normal erectile function, erection of penis length up to 10cm and 11cm, can meet the requirements of life. The other two patients failed to fol ow-up. Conclusion Partial resection of penis lengthening for good clinical ef ects in patients with early carcinoma of penis desirable.%目的:观察阴茎部分切除同期延长术治疗青壮年阴茎癌要求保留性功能患者的疗效。方法对4例Ⅰ期(T1-2N0M0)阴茎癌患者行阴茎部分切除同期延长术,观察治疗效果。结果2例患者随访18个月,患者勃起功能正常,阴茎勃起长度达10 cm及11 cm,能够满足性生活要求。另外2例高龄患者未能随访。结论阴茎部分切除同期延长术对于早期阴茎癌患者可取的一定的临床效果,达到治疗目的。

  4. TGF-β in cancer and bone: implications for treatment of bone metastases.

    Science.gov (United States)

    Juárez, Patricia; Guise, Theresa A

    2011-01-01

    Bone metastases are common in patients with advanced breast, prostate and lung cancer. Tumor cells co-opt bone cells to drive a feed-forward cycle which disrupts normal bone remodeling to result in abnormal bone destruction or formation and tumor growth in bone. Transforming growth factor-beta (TGF-β) is a major bone-derived factor, which contributes to this vicious cycle of bone metastasis. TGF-β released from bone matrix during osteoclastic resorption stimulates tumor cells to produce osteolytic factors further increasing bone resorption adjacent to the tumor cells. TGF-β also regulates 1) key components of the metastatic cascade such as epithelial-mesenchymal transition, tumor cell invasion, angiogenesis and immunosuppression as well as 2) normal bone remodeling and coupling of bone resorption and formation. Preclinical models demonstrate that blockade of TGF-β signaling is effective to treat and prevent bone metastases as well as to increase bone mass.

  5. CT assisted biomimetic artificial bone des

    Institute of Scientific and Technical Information of China (English)

    WANG Xian-gang; ZHANG Chao-zong; GUO Zhi-ping; TIAN Jie-mo

    2001-01-01

    @@ In the recent years, bioceramic materials have been widely used in the clinics. They are mainly fabricated as the substitution of human hard tissue, such as artificial bone and false tooth. As a medical implant, those that have similar structure to human bone have better biocompatibility and osteoinductional property. So it is necessary to design bone model close to human bone.

  6. Biochemical parameters of bone metabolism in bone metastases of solid tumors (Review)

    NARCIS (Netherlands)

    Meijer, Wilhelmus; van der Veer, E; Willemse, P H

    1998-01-01

    The role of biochemical markers of bone metabolism in the diagnosis and monitoring of bone metastases in solid tumors is reviewed. Emphasis is on the recently developed markers, which may provide a more accurate quantitation of bone metabolism. In metastatic bone disease, bone formation and resorpti

  7. Factors affecting bone strength other than osteoporosis.

    Science.gov (United States)

    Ratti, Chiara; Vulcano, Ettore; Canton, Gianluca; Marano, Marco; Murena, Luigi; Cherubino, Paolo

    2013-10-01

    Osteoporosis is the most common cause of bone fragility, especially in post-menopausal women. Bone strength may be compromised by several other medical conditions and medications, which must be ruled out in the clinical management of patients affected by fragility fractures. Indeed, 20-30% of women and up to 50% of men affected by bone fragility are diagnosed with other conditions affecting bone strength other than osteoporosis. These conditions include disorders of bone homeostasis, impaired bone remodeling, collagen disorders, and medications qualitatively and quantitatively affecting bone strength. Proper diagnosis allows correct treatment to prevent the occurrence of fragility fractures. PMID:24046057

  8. Bone Anchored Hearing Treatment Procedure

    Medline Plus

    Full Text Available ... implanted, the Baha device will allow sound to travel through bone and restore close-to-normal hearing ... through the abutment so the sound can then travel through the head to the functional cochlea, or ...

  9. Bone Anchored Hearing Treatment Procedure

    Medline Plus

    Full Text Available ... and out. It's important that we don't heat the bone up too much. And you can ... way give her -- help her get over the challenges that single-sided deafness presents. But important to ...

  10. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... assist in the detection and diagnosis of bone cancer . locate foreign objects in soft tissues around or ... Risks There is always a slight chance of cancer from excessive exposure to radiation. However, the benefit ...

  11. Drugs Approved for Bone Cancer

    Science.gov (United States)

    This page lists cancer drugs approved by the Food and Drug Administration (FDA) for bone cancer. The list includes generic names and brand names. The drug names link to NCI's Cancer Drug Information summaries.

  12. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... more useful in identifying bone and joint injuries (e.g., meniscal and ligament tears in the knee, ... a comment, please complete the following form: Comment: E-mail: Area code: Phone no: Images × Image Gallery ...

  13. Oral Health and Bone Disease

    Science.gov (United States)

    ... for periodontitis and tooth loss. Role of the Dentist and Dental X Rays Research supported by the ... normal bone density. Because many people see their dentist more regularly than their doctor, dentists are in ...

  14. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... for your doctor to view and assess bone fractures, injuries and joint abnormalities. This exam requires little ... stabilization of bony fragments following treatment of a fracture. guide orthopedic surgery, such as spine repair/fusion, ...

  15. Treatment of Temporal Bone Fractures.

    Science.gov (United States)

    Diaz, Rodney C; Cervenka, Brian; Brodie, Hilary A

    2016-10-01

    Traumatic injury to the temporal bone can lead to significant morbidity or mortality and knowledge of the pertinent anatomy, pathophysiology of injury, and appropriate management strategies is critical for successful recovery and rehabilitation of such injured patients. Most temporal bone fractures are caused by motor vehicle accidents. Temporal bone fractures are best classified as either otic capsule sparing or otic capsule disrupting-type fractures, as such classification correlates well with risk of concomitant functional complications. The most common complications of temporal bone fractures are facial nerve injury, cerebrospinal fluid (CSF) leak, and hearing loss. Assessment of facial nerve function as soon as possible following injury greatly facilitates clinical decision making. Use of prophylactic antibiotics in the setting of CSF leak is controversial; however, following critical analysis and interpretation of the existing classic and contemporary literature, we believe its use is absolutely warranted. PMID:27648399

  16. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... top of page What are the benefits vs. risks? Benefits Bone x-rays are the fastest and ... in the typical diagnostic range for this exam. Risks There is always a slight chance of cancer ...

  17. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... current x-ray images for diagnosis and disease management. top of page How is the procedure performed? ... top of page What are the benefits vs. risks? Benefits Bone x-rays are the fastest and ...

  18. Bone growth in electric fields

    International Nuclear Information System (INIS)

    Research performed in several laboratories has shown that artificially induced currents affect bone growth. Studies of various current characteristics produced by implanted electrodes indicate that continuous dc, interrupted dc, and asymmetric ac all increase osteogenesis at the cathode. Stimulation from an externally applied balanced ac field was reported to reduce bone loss from disuse. The purpose of the study being reported here was to examine the influence of a uniform ac electric field on the normal skeletal growth pattern of rats. Juvenile rats received whole body exposure to uniform, vertical 60-Hz electric fields at 100 kV/m for 30 days. There were no marked alterations in the general growth pattern of the exposed animals compared to controls maintained under similar conditions. Bone growth rate, measured by tetracycline labeling, morphology of lumbar vertebrae and tibias and cortical bone area and marrow space area of tibias were not disturbed by exposure to the electric fields. (author)

  19. Bone X-Ray (Radiography)

    Medline Plus

    Full Text Available ... the body absorb the x-rays in varying degrees. Dense bone absorbs much of the radiation while ... is further reviewed by committees from the American College of Radiology (ACR) and the Radiological Society of ...

  20. Healthy Bones at Every Age

    Science.gov (United States)

    ... include walking and running, as well as team sports like soccer and basketball. AAOS does not endorse ... to cause hormonal changes that stop menstrual periods (amenorrhea). This loss of estrogen can cause bone loss ...